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Aberrant adipogenic differentiation is strongly associated with obesity and related metabolic diseases. Elucidating the key factors driving adipogenesis is an effective strategy for identifying novel therapeutic targets for treating metabolic diseases represented by obesity. In this study, transcriptomic techniques were employed to investigate the functional genes that regulate adipogenic differentiation in OP9 cells and 3T3-L1 cells. The findings indicated a notable upregulation of Acsl1 expression throughout the adipogenic differentiation process. Knocking down Acsl1 led to a decrease in the expression of genes associated with adipogenesis and a reduction in triglyceride accumulation. Additionally, Acsl1 overexpression promoted adipocyte differentiation and adipose-specific overexpression of Acsl1 markedly aggravated steatosis induced by a high-fat diet. Mechanistically, Cyp2f2, Dusp23 and Gstm2 are the crucial genes implicated in Acsl1-induced adipogenic differentiation. The findings of this study indicate that Acsl1 promotes adipogenesis and could serve as a potential therapeutic target for treating obesity and related metabolic disorders., Competing Interests: Declaration of competing interest The author declares no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The 4-coumarate coenzyme A ligase (4CL) plays a critical role in the phenylpropane metabolic pathway and is a key enzyme in plant growth metabolism and stress responses. Using bioinformatics methods, 50 Me4CL gene were identified within the cassava genome u, and a comprehensive analysis of the cassava 4CL gene family was conducted. The results showed that these 50 4CL proteins are divided into four subfamilies, with members within the same subfamily sharing similar or identical gene structures. Co-linearity analysis revealed that cassava and rubber trees have the highest number of homologous genes, indicating a close homologous relationship between them. Analysis of 20 cis-acting elements in the promoter region of Me4CL32 revealed the presence of hormone-responsive elements such as gibberellin, auxin, abscisic acid, and as well as elements related to meristematic tissue regulation. results Quantitative real-time PCR (qRT-PCR) results showed that Me4CL32 gene expression changes in response to abiotic stressors (drought, salt, cold, heat) and hormonal stimuli(GA3 and ABA), indicating that Me4CL32 can respond to both environmental pressures and hormone signals. RNA-seq transcriptome and single-cell transcriptome analyses were used to examine the expression patterns of Me4CLs. Additionally, subcellular localization studies demonstrated that the Me4CL32 protein is confined to the chloroplasts of cassava leaves.Investigating the functionality of this gene family aids in comprehending plant growth, development, and stress resistance mechanisms. Furthermore, it furnishes a theoretical basis for future research on developing resilient cassava germplasm and the enhancing cassava's environmental tolerance., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024. Published by Elsevier Inc.)

The Pseudomonas putida F1 genome and those of many other pseudomonads contain two tandem genes encoding acyl-CoA ligases Pput_1340 ( fadD1 ) and Pput_1339 ( fadD2 ) with Pput_1339 ( fadD2 ) being the upstream gene. The fadD designation was assigned when both genes were found to complement the growth of an Escherichia coli acyl-CoA synthetase fadD deletion strain with oleic acid as sole carbon source. Site-directed mutagenesis showed that residues of the ATP/AMP domain required for function of E. coli FadD were also essential for full function of FadD1 and FadD2. Growth of the constructed ∆ fadD1 , ∆ fadD2, and ∆ fadD1 ∆ fadD2 strains was tested in minimal medium with different chain length fatty acids as sole carbon sources. Lack of FadD1 significantly retarded growth with different chain length fatty acids and lack of both FadD1 and FadD2 further retarded growth. Derivatives of the ∆ fabA ∆ desA unsaturated fatty acid auxotrophic strain carrying a deletion of either ∆ fadD1 or ∆ fadD2 were constructed. Growth of the ∆ fabA ∆ desA ∆ fadD1 strain was very weak, whereas the ∆ fabA ∆ desA ∆ fadD2 strain grew as well as the ∆ fabA ∆ desA parent strain. Overexpression of either fadD1 or fadD2 restored growth of the ∆ fabA ∆ desA ∆ fadD1 strain with fadD2 overexpression having a greater effect than fadD1 overexpression. The ∆ fadD1 or ∆ fadD2 genes are cotranscribed although the expression level of fadD1 is much higher than that of fadD2 . This is attributed to a fadD1 promoter located within the upstream FadD2 coding sequence., Importance: Pseudomonas bacteria demonstrate a great deal of metabolic diversity and consequently colonize a wide range of ecological niches. A characteristic of these bacteria is a pair of genes in tandem annotated as acyl-CoA ligases involved in fatty acid degradation. The Pseudomonas putida F1 genome is annotated as having at least nine genes encoding acyl-CoA ligases which are scattered around the chromosome excepting the tandem pair. Since similar tandem pairs are found in other pseudomonads, we have constructed and characterized deletion mutants of the tandem ligases. We report that the encoded proteins are authentic acyl-CoA ligases involved in fatty acid degradation., Competing Interests: The authors declare no conflict of interest.

Background: The response of hepatocellular carcinoma (HCC) to transarterial chemoembolization (TACE) treatment and its underlying mechanisms remain elusive. This study investigates the role of enzymes involved in fatty acid activation, specifically Acyl-CoA synthetase long chain 4 (ACSL4), in HCC patients treated with postoperative adjuvant TACE (PA-TACE) and in nutrient-deprived HCC cells., Methods: We examined the expression of ACSL4 and its family members in HCC clinical samples and cell lines. The clinical significance of ACSL4, particularly regarding the prognosis of patients treated with PA-TACE, was assessed using two independent HCC cohorts. We further explored the role of ACSL4 in glucose starvation-induced cell death in HCC cells and xenograft mouse models., Results: Among the family members, ACSL4 is the most up-regulated enzyme, associated with poor survival in HCC patients, particularly in post-recurrent TACE-treated patients in a Singapore cohort. ACSL4 is essential for HCC cell survival in response to glucose starvation, rather than to hypoxia or to the combination of hypoxia with doxorubicin or cisplatin. ACSL4-mediated arachidonic acid (AA) metabolism supports mitochondrial β-oxidation and energy production. CCAAT/enhancer binding protein α (CEBPA) transcriptionally regulates ACSL4 by binding 3 motifs (-623 to -613, -1197 to -1187 and -1745 to -1735) of ACSL4 upstream promoter region, enhancing its pro-survival effects. Furthermore, canagliflozin (Cana), a clinical-approved drug for type 2 diabetes, mimics glucose starvation and inhibits the growth of ACSL4-low xenograft tumors. Moreover, high ACSL4 or CEBPA expressions correlate with increased recurrence susceptibility after PA-TACE in the China-Guangxi HCC cohort., Conclusions: The CEBPA-ACSL4 pathway is critical in protecting HCC cells from glucose starvation-induced cell death, suggesting that ACSL4 and CEBPA could serve as valuable prognostic indicators and potential therapeutic targets in the context of PA-TACE treatment for HCC., Competing Interests: Declarations Ethics approval and consent to participate The studies involving two HCC cohorts were conducted with approval from the National Healthcare Group Domain Specific Review Board (NHG DSRB Ref: 2011/01580) and the Guangxi Medical University Institutional Review Board (GXMU #20160302–10). Informed consent was obtained from all patients participating in the study. All animal experiments were approved by the Guangxi Medical University Institutional Animal Care and Use Committees (#201910029) and performed in accordance with the Association for Assessment and Accreditation of Laboratory Animal Care guidelines. Consent for publication The consents for publication from all authors were obtained. Competing interests The authors declare that they have no conflicts of interest., (© 2024. The Author(s).)

Diabetes-induced neuropathy represents a major etiology of dementia, highlighting an urgent need for the development of effective therapeutic interventions. In this study, we explored the role of fibronectin type III domain containing 5 (FNDC5)/Irisin in mitigating hyperglycemia-induced neurotoxicity in HT22 cells and investigated the underlying mechanisms. Our findings reveal that high glucose conditions are neurotoxic, leading to reduced viability of HT22 cells and increased apoptosis. Furthermore, the elevated expression of the intracellular ferroptosis marker Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4), along with increased levels of ferrous ions and malondialdehyde (MDA), suggests that high glucose conditions may induce ferroptosis in HT22 cells. FNDC5/Irisin treatment effectively mitigates high glucose-induced neurotoxicity and ferroptosis in HT22 cells. Mechanistically, FNDC5/Irisin enhances cellular antioxidant capacity, regulates ACSL4 expression, and improves intracellular redox status, thereby inhibiting ferroptosis and increasing HT22 cell survival under high-glucose conditions. These results highlight the neuroprotective potential of FNDC5/Irisin in high glucose environments, offering a promising avenue for developing treatments for diabetes-related neurodegenerative diseases.

Key Message: Established an Agrobacterium-mediated hairy root transformation system for gene function analysis in Lathyrus sativus. Arabidopsis mutant complementation and genome editing in Lathyrus confirmed role of LsOCS in the oxalate metabolism. Grass pea (Lathyrus sativus) is a resilient legume cultivated for its protein-rich seeds and fodder. However, the presence of a naturally occurring neurotoxin, β-N-oxalyl-L-α,β-diaminopropionic acid (β-ODAP), which causes neurolathyrism, limits its extensive cultivation. This paper reports the in-planta characterization of oxalyl-CoA synthetase (OCS), an enzyme involved in oxalate metabolism and important in the oxalylating step leading to β-ODAP production in Lathyrus. For this, we used complementation experiments in an Arabidopsis OCS mutant. The LsOCS-complemented lines showed oxalate content similar to wild-type levels, and the analysis of seeds by field emission scanning electron microscope (FESEM) showed that the LsOCS-complemented lines were rescued from seed-coat defects found in the mutant seeds. We used genome editing of LsOCS in Lathyrus hairy roots to further characterize LsOCS function. The mutations in LsOCS resulted in the accumulation of oxalate in the hairy roots of Lathyrus, as observed in Arabidopsis mutants, but did not affect the ODAP levels. The hairy root genome editing system could serve as a rapid tool for functional studies of Lathyrus genes and optimizing the agronomic traits., Competing Interests: Declarations Conflict of interest No conflict of interest declared., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Mitochondrial dysfunction, characterized by impaired lipid metabolism and heightened reactive oxygen species generation, results in lipid peroxidation and ferroptosis. Ferroptosis is an inflammatory mode of cell death that promotes complement activation and macrophage recruitment. In pulmonary arterial hypertension (PAH), pulmonary arterial endothelial cells exhibit cellular phenotypes that promote ferroptosis. Moreover, there is ectopic complement deposition and inflammatory macrophage accumulation in the pulmonary vasculature. However, the effects of ferroptosis inhibition on these pathogenic mechanisms and the cellular landscape of the pulmonary vasculature are incompletely defined., Methods: Multiomics and physiological analyses evaluated how ferroptosis inhibition-modulated preclinical PAH. The impact of adeno-associated virus 1-mediated expression of the proferroptotic protein ACSL (acyl-CoA synthetase long-chain family member) 4 on PAH was determined, and a genetic association study in humans further probed the relationship between ferroptosis and pulmonary hypertension., Results: Ferrostatin-1, a small-molecule ferroptosis inhibitor, mitigated PAH severity in monocrotaline rats. RNA-sequencing and proteomics analyses demonstrated ferroptosis was associated with PAH severity. RNA-sequencing, proteomics, and confocal microscopy revealed complement activation and proinflammatory cytokines/chemokines were suppressed by ferrostatin-1. In addition, ferrostatin-1 combatted changes in endothelial, smooth muscle, and interstitial macrophage abundance and gene activation patterns as revealed by deconvolution RNA-sequencing. Ferroptotic pulmonary arterial endothelial cell damage-associated molecular patterns restructured the transcriptomic signature and mitochondrial morphology, promoted the proliferation of pulmonary artery smooth muscle cells, and created a proinflammatory phenotype in monocytes in vitro. Adeno-associated virus 1- Acsl4 induced an inflammatory PAH phenotype in rats. Finally, single-nucleotide polymorphisms in 6 ferroptosis genes identified a potential link between ferroptosis and pulmonary hypertension severity in the Vanderbilt BioVU repository., Conclusions: Ferroptosis promotes PAH through metabolic and inflammatory mechanisms in the pulmonary vasculature., Competing Interests: K.W. Prins received grant funding from Bayer unrelated to this article. The other authors report no conflicts.

Enzymatic platforms for producing malonyl-CoA-based extender units required for polyketide biosynthesis are often based on malonyl-CoA ligases such as MatB from Rhizobium trifolii and Rhodopseudomonas palustris. However, despite broad interest in the fluorination of polyketides and prior success with engineering MatB homologs, the suitability of MatB for accessing the tertiary substituted fluoromethylmalonyl-CoA needed to produce flurithromycin and solithromycin has not yet been reported. Herein, we report the structure-guided engineering of a MatB homolog to optimize the production of fluoromethylmalonyl-CoA, resulting in a variant with increased conversion and providing a platform to produce a suitable building block mixture for fluorinated macrolide production. Additionally, the mutant demonstrated broad utility for various substituted malonyl-CoAs. The MatB mutant sets the stage to access fluorinated macrolides by coupling it with altered PKS machinery to install fluorinated malonyl-CoA into macrolide scaffolds., (© 2024 The Authors. ChemBioChem published by Wiley-VCH GmbH.)

Pulmonary fibrosis is a chronic interstitial lung disease with no curative therapeutic treatment, leading to significant mortality. The aims of this study were to investigate the regulatory mechanisms of mitophagy in the progression of pulmonary fibrosis. Through bioinformatics analysis, we identified the downregulation of long-chain fatty acyl-CoA synthetase 1 (ACSL1) as being associated with the severity of pulmonary fibrosis. A pulmonary fibrosis model was established through bleomycin (BLM) exposure both in vivo and in vitro. Mitoquinone (MitoQ) pretreatment significantly decreased redox damage, stabilized mitochondrial membrane potential (MMP), improved mitochondrial dynamics, and activated PINK1/Parkin-mediated mitophagy, thereby alleviating pulmonary fibrosis. In vitro, overexpression of ACSL1 mitigated mitochondrial damage and restored PINK1/Parkin-mediated mitophagy under BLM exposure. In contrast, ACSL1 inhibition exacerbated pulmonary fibrosis, and these adverse effects could not be reversed by MitoQ treatment. Taken together, our study reveals a novel mechanism underlying the pathogenesis of pulmonary fibrosis and suggests a potential therapeutic target for its treatment., (© 2024. The Author(s).)

Clear cell renal cell carcinoma (ccRCC) is a common genitourinary malignancy characterized by dysregulated cellular metabolism leading to aberrant glucose metabolism, fatty acid accumulation, and excessive reactive oxygen species production. ccRCC cells exhibit an augmented oxidative stress response. Complex interactions between iron metabolism and lipid homeostasis in ccRCC cells require a counteracting response that enables ferroptosis evasion and survival maintenance. Additionally, abnormal GA-binding protein transcription factor subunit alpha (GABPA) expression is associated with ccRCC occurrence and development, but its impact on ferroptosis-related molecular mechanisms remains unclear. Herein, we examined the impact of the GABPA-ACSL4 pathway on ferroptosis in ccRCC through bioinformatics analysis, as well as in vitro and in vivo experiments. In contrast to that in adjacent normal tissues, GABPA expression was significantly downregulated in ccRCC tissues, and this downregulation was linked to poor overall survival. Increased GABPA expression suppressed ccRCC cell proliferation, migration, and invasion. Moreover, GABPA overexpression increased the susceptibility of ccRCC cells to ferroptosis. Additionally, GABPA directly bound to the promoter region of ACSL4, promoting ferroptosis. Thus, inducing the GABPA-ACSL4 pathway activates ferroptosis, inhibits proliferation or metastasis, and exerts anticancer activity in ccRCC. These findings have important implications for regulating ccRCC occurrence and development., (© 2024. The Author(s).)

Aims: Tumor fatty acid (FA) metabolic plasticity plays a pivotal role in resistance to therapy and poses limitations to anticancer strategies. In this study, our aim is to uncover the role of acetate metabolism in neurodifferentiation (NED)-mediated castration-resistant prostate cancer (CRPC)., Methods: We conducted analyses using LC-MS/MS on clinical prostate cancer tissue before and after hormone therapy. We established tumor xenograft mouse models, primary tumor cells, and human-derived organoids to detect the novel mechanism of NED and to identify potential therapies., Results: The hormone therapy-induced upregulation of acetate metabolism was mediated by acyl-CoA synthetase short-chain family member 2 (ACSS2), which increased c-MYC expression for NED induction. Notably, combined treatment with an ACSS2 inhibitor and enzalutamide significantly reduced the xenograft tumor volume., Conclusion: Our findings uncovered the critical role of acetate metabolism in NED-mediated CRPC and suggest that ACSS2 inhibitors may represent a novel, low-toxicity strategy when combined with hormone therapy for treating patients with NED-mediated CRPC., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests. Huan Xu reports financial support was provided by National Natural Science Foundation of China. Huan Xu reports financial support was provided by National Natural Science Foundation of China. Huan Xu reports financial support was provided by Shanghai Sailing Program. Zhong Wang reports financial support was provided by National Natural Science Foundation of China. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Acute respiratory distress syndrome (ARDS) is a critical disorder characterized by immune-related damage to epithelial cells; however, its underlying mechanism remains elusive. This study investigated the effects of alterations in microRNA (miRNA) expression in mast cell-derived exosomes on human bronchial epithelial (HBE) cells and ARDS development in cellular and mouse models challenged with lipopolysaccharide. Lipopolysaccharide-treated mast cell-derived exosomes reduced glutathione peroxidase 4 (GPX4) expression and increased long-chain acyl-CoA synthetase 4 (ACSL4), 15-lipoxygenase (ALOX15), and inflammatory mediator levels in HBE cells. miRNA sequencing revealed a reduction in mast cell-derived exosomal miR-744 levels, which was associated with the regulation of ACSL4, ALOX15, and GPX4 expression. This downregulation of exosomal miR-744 expression reduced miR-744 levels and promoted ferroptosis in HBE cells, whereas the experimental upregulation of miR-744 reversed these adverse effects. Down-regulation of miR-744 induced the expression of markers for ferroptosis and inflammation in HBE cells and promoted pulmonary ferroptosis, inflammation, and injury in LPS-stimulated mice. In vivo, treatment with ACSL4, ALOX15, and GPX4 inhibitors mitigated these effects, and experimental miR-744 expression rescued the lipopolysaccharide-induced changes in HBE cells and mouse lungs. Notably, miR-744 levels were reduced in the plasma and exosomes of patients with ARDS. We concluded that decreased mast cell-derived exosomal miR-744 levels trigger epithelial cell ferroptosis, promoting lung inflammation and damage in ARDS. This study provides new mechanistic insights into the development and sustained pulmonary damage associated with ARDS and highlights potential therapeutic strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

The use of gentamicin (GNT) is associated with acute kidney injury (AKI). Ferroptosis is a newly recognized iron-dependent, non-apoptotic cell death that can lead to AKI. Lactoferrin (LF), an iron-binding glycoprotein, was previously reported to be renoprotective. Nonetheless, LF's impact on GNT-induced AKI and ferroptosis has not yet been investigated. Accordingly, we assessed the dose-dependent effect of LF on GNT-induced AKI and its influence on ferroptosis. Thirty-six male rats were allocated as control, LF, GNT (100 mg/kg/day, i.p.), and groups given LF (100, 200, and 300 mg/kg, p.o.) for 14 days prior concurrently with GNT (Day 8-14). The high dose of LF (300 mg/kg) showed better histopathological picture, higher creatinine clearance, reduced serum and urine levels of kidney injury markers when compared to the GNT group and the lower two doses. These nephroprotective effects of LF can be attributed to the observed reduction in renal ferrous iron, 4-HNE, and MDA, miR-378a-3p and ALOX15 expression, TFR1, NCOA4, and ACSL4 protein expression and the increased LINC00618 expression, GSH levels, GPX4, SLC7A11, and FSP1 protein expression. In conclusion, LF high dose was the most renoprotective against GNT-induced AKI, in which suppression of ferroptosis pathways was a likely contributor to its protective mechanism., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

To investigate the effect of p-coumaric acid (p-CA) on postharvest cherry tomatoes, breaker stage fruits were treated with p-CA to analyze the physiological metabolism during storage. The results showed that exogenous p-CA treatment improved the sensory quality of tomato fruits. Transcriptomics results indicated that 782 genes (339 up-regulated and 443 down-regulated) were differentially expressed between p-CA treated and control fruits. Results suggested that p-CA treatment regulated the synthesis of phenolic compounds and inhibited the fruit ripening through the pathways of mangiferic acid biosynthesis and phenylalanine metabolism. Key enzymes activities of the phenylpropane metabolic pathway of tomato fruits were increased, including phenylalanine ammonia lyase (PAL), cinnamic acid 4-hydroxylase (C4H), and 4-coumarate-CoA ligase (4CL). In addition, the total phenols content, flavonoids content and antioxidant capacities of tomato fruits were improved with p-CA treatment. Overall, these findings showed that p-CA treatment could be a potential strategy for fruit and vegetable preservation., (© 2024 Institute of Food Technologists.)

Rabies, induced by rabies virus (RABV), still threaten global health all over the world, and no effective therapy is available for rabies currently. Recently, a series of natural plant components have been found to inhibit virus production. In this study, Z-Ligustilide, a natural component of Ligusticum chuanxiong Hort, was found to inhibit RABV replication. Initially, the concentration of cytotoxicity 50 % (CC 50 ) of Z-Ligustilide in N2a and BSR cells were 429.9 μM and 335.5 μM, respectively, which both significantly restrict RABV production in a concentration-dependent manner. Moreover, Z-Ligustilide was found to mainly inhibit the replication stage of RABV. Specifically, Z-Ligustilide can suppress lipid droplet (LD) formation via directly inhibiting diacylglycerol acyltransferase 1/2 (DGAT1/2) expression, which can further promote cellular lipid peroxidation, Fe 2+ concentration, reactive oxygen species (ROS), and induce ferroptosis ultimately. Furthermore, Z-Ligustilide was demonstrated to increase ferroptosis via Acyl-CoA synthetase long-chain family member 4 (ACSL4)- Lysophosphatidylcholine Acyltransferase 3 (LPCAT3)- Cytochrome P450 Oxidoreductase (POR) pathway. Above all, this study explored the antiviral function of Z-Ligustilide, which provides a novel insight for developing anti-RABV drugs., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest, (Copyright © 2024 Elsevier B.V. All rights reserved.)

Ferroptosis is a recently discovered form of regulated cell death that shows promise as a novel approach for inducing tumor cell death in cancer treatment, with significant research potential. Asiatic acid (AA), a key component of the traditional Chinese medicine Centella asiatica, has been identified as having potential therapeutic benefits for various diseases, particularly cancer. Non-small cell lung cancer (NSCLC) is a challenging and prevalent form of cancer to treat. In our study, we utilized network pharmacology, molecular docking, and experimental methods to investigate the potential of AA in treating NSCLC and to elucidate its role in inhibiting cancer through the ferroptosis pathway. Through network pharmacology analysis, we identified that AA targets the core NSCLC protein SRC through the ferroptosis pathway. Our experiments demonstrated that treatment with AA led to increased iron accumulation, mitochondrial membrane potential, and expression of ferroptosis markers glutathione peroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), and acyl-CoA synthetase long chain family member 4 (ACSL4) in NSCLC cells, confirming the induction of ferroptosis. In conclusion, AA has the potential to target SRC and induce NSCLC cell death through the ferroptosis pathway, offering a promising approach for cancer treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Osteosarcoma (OS) is the most common primary malignant tumor of bone. The aim of this study was to investigate the regulatory mechanisms of M2 macrophage exosomes (M2-Exos) in ferroptosis in OS. A mouse model was established to investigate the in vivo role of M2-Exos. We investigated their effects on ferroptosis in OS using erastin, a ferroptosis activator, and deferoxamine mesylate, an iron chelator. In vitro, we investigated whether the Apoc1/Acyl-CoA Synthetase Family Member 2 (ACSF2) axis mediates these effects, using shApoc1 and shACSF2. The mechanisms whereby Apoc1 regulates ACSF2 were examined using cyclohexanone, a protein synthesis inhibitor, and MG132, a proteasomal inhibitor. M2-Exos reversed the inhibitory effects of erastin on OS cells, thus enhancing their viability, migration, invasion, proliferation, and reducing ferroptosis. Apoc1 was highly expressed in M2-Exos, and interfering with this expression reversed the effects of M2-Exos on OS cells. ACSF2 mediated the effects of M2-Exos-derived Apoc1. Apoc1 interacted with ACSF2, which, in turn, interacted with USP40. Apoc1 overexpression increased ACSF2 ubiquitination, promoting its degradation, whereas USP40 overexpression inhibited ACSF2 ubiquitination and promoted its expression. Apoc1 overexpression inhibited ACSF2 binding to USP40. M2-Exos-derived Apoc1 promoted ferroptosis resistance by inhibiting USP40 binding to ACSF2 and promoting ACSF2 ubiquitination and degradation, thus enhancing OS development., (© 2024 Wiley Periodicals LLC.)

Cigarette smoke (CS) is an important indoor air pollutant associated with an increased risk of ocular surface disease. As the eye's outermost layer, the cornea is highly sensitive to air pollutants like CS. However, the specific mechanisms linking CS exposure to corneal dysfunction have not been fully elucidated. In the present study, we found that CS exposure damages corneal epithelial cells, accompanied by increased iron (Fe 2+ ) levels and lipid peroxidation, both hallmarks of ferroptosis. Ferroptosis inhibitors, including Ferrostatin-1 (Fer-1) and Deferoxamine mesylate (DFO), protect against CS-induced cell damage. To understand the underlying mechanisms, we investigated how CS affects iron and lipid metabolism. Our results showed that CS could upregulate intracellular iron levels by increasing TFRC expression and promote lipid peroxidation by increasing ACSL4 expression. Silencing ACSL4 or TFRC expression prevented CS-induced ferroptosis. Furthermore, we found that the upregulation of TFRC and ACSL4 was driven by increased YAP transcription. Pharmacological or genetic inhibition of YAP effectively prevented corneal epithelial cell ferroptosis under CS stimulation. Additionally, our results suggest that CS exposure could increase O-GlcNAc transferase activity, leading to YAP O-GlcNAcylation. This glycosylation of YAP interfered with its K48-linked ubiquitination, resulting in YAP stabilization. Collectively, we found that CS exposure induces corneal epithelial cell ferroptosis via the YAP O-GlcNAcylation, and provide evidence that CS exposure is a strong risk factor for ocular surface disease., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objective: To investigate the mechanism of induction of ferroptosis by brazilin in breast cancer cells., Methods: Breast cancer 4T1 cells were divided into 6 groups: control, brazilin 1/2 half maximal inhibitory concentration (IC 50 ), IC 50 , 2×IC 50 , erastin (10 µg/mL) and capecitabine (10 µg/mL) groups. The effect of brazilin on the proliferation of 4T1 cells was detected by cell counting kit-8 assay, and the treatment dose of brazilin was screened. The effect of brazilin on the mitochondrial morphology of 4T1 cells, and the mitochondrial damage was evaluated under electron microscopy. The levels of Fe 2+ , reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH) and glutathione peroxidase 4 (GPX4) were estimated using various detection kits. The invasion and migration abilities of 4T1 cells were detected by scratch assay and transwell assay. The expressions levels of tumor protein p53, solute carrier family 7 member 11 (SLC7A11), GPX4 and acyl-CoA synthetase long-chain family member 4 (ACSL4) proteins were quantified by Western blot assay., Results: Compared to the control group, the 10 (1/2 IC 50 ), 20 (IC 50 ) and 40 (2×IC 50 ) µg/mL brazilin, erastin, and capecitabine groups showed a significant decrease in the cell survival rate, invasion and migration abilities, GSH, SLC7A11 and GPX4 protein expression levels, and mitochondrial volume and ridge (P<0.05), and a significant increase in the mitochondria membrane density, Fe 2+ , ROS and MDA levels, and p53 and ACSL4 protein expression levels (P<0.05)., Conclusions: Brazilin actuated ferroptosis in breast cancer cells, and the underlying mechanism is mainly associated with the p53/SLC7A11/GPX4 signaling pathway., (© 2024. The Chinese Journal of Integrated Traditional and Western Medicine Press and Springer-Verlag GmbH Germany, part of Springer Nature.)

Hyperglycaemia-induced ferroptosis is a significant contributor to kidney dysfunction in diabetic nephropathy (DN) patients. In addition, targeting ferroptosis has clinical implications for the treatment of DN. However, effective therapeutic targets for ferroptosis have not been identified. In this study, we aimed to explore the precise role of protein arginine methyltransferase 6 (PRMT6) in regulating ferroptosis in DN. In the present study, we utilized a mouse DN model consisting of both wild-type and PRMT6-knockout (PRMT6 -/- ) mice. Transcriptomic and lipidomic analyses, along with various molecular biological methodologies, were used to determine the potential mechanism by which PRMT6 regulates ferroptosis in DN. Our results indicate that PRMT6 downregulation participates in kidney dysfunction and renal cell death via the modulation of ferroptosis in DN. Moreover, PRMT6 reduction induced lipid peroxidation by upregulating acyl-CoA synthetase long-chain family member 1 (ACSL1) expression, ultimately contributing to ferroptosis. Furthermore, we investigated the molecular mechanism by which PRMT6 interacts with signal transducer and activator of transcription 1 (STAT1) to jointly regulate ACSL1 transcription. Additionally, treatment with the STAT1-specific inhibitor fludarabine delayed DN progression. Furthermore, we observed that PRMT6 and STAT1 synergistically regulate ACSL1 transcription to mediate ferroptosis in hyperglycaemic cells. Our study demonstrated that PRMT6 and STAT1 comodulate ACSL1 transcription to induce the production of phospholipid-polyunsaturated fatty acids (PL-PUFAs), thus participating in ferroptosis in DN. These findings suggest that the PRMT6/STAT1/ACSL1 axis is a new therapeutic target for the prevention and treatment of DN., (© 2024. The Author(s), under exclusive licence to ADMC Associazione Differenziamento e Morte Cellulare.)

Oltipraz (OPZ) is a synthetic dithiolethione and is considered a novel activator of nuclear factor E2-related factor 2 (Nrf2). Increasing evidence indicates that Nrf2 protects against cerebral ischemia/reperfusion (I/R) injury by antagonizing ferroptosis and lipid peroxidation. However, the protective effects of OPZ on cerebral I/R injury remain to be elucidated. We investigated the in vitro and in vivo neuroprotective effects of OPZ. Mice were subjected to middle cerebral artery occlusion/reperfusion (MCAO/R) to construct an in vivo model and PC12 cells were exposed to oxygen and glucose deprivation/reoxygenation (OGD/R) to establish an in vitro model. OPZ administration reduced the infarct volume and brain water content, and alleviated the neurological deficit of MCAO/R mice. Moreover, OPZ ameliorated MCAO/R-induced oxidative stress by decreasing the levels of 4-HNE and MDA and increasing the activities of SOD and GSH. We also found that OPZ ameliorated MCAO/R-induced ferroptosis by increasing SLC7A11 and GPX4 protein expression and downregulating ACSL4 protein expression. Similarly, the in vitro results revealed that OGD/R-induced oxidative stress and ferroptosis. Finally, mechanistic analysis revealed that OPZ significantly upregulated the Nrf2 expression and Nrf2 knockout (Nrf2 KO) abolished the OPZ-mediated protective effects. Taken together, these findings demonstrate that OPZ ameliorates cerebral I/R injury by suppressing the oxidative stress and ferroptosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

This study analyzed transcriptomic and proteomic data to identify molecular changes during heart failure (HF). Additionally,we embarked on an exploration of the prospect of therapeutic intervention through the manipulation of proteins implicated in ferroptosis. Three publicly available microarray datasets (GSE135055, GSE147236, GSE161472) profiling left ventricular samples from HF patients and healthy controls were obtained. Differentially expressed genes were identified in each dataset and cross-analyzed to determine shared gene signatures. Enrichment analysis of Gene Ontology (GO) terms, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and gene set enrichment analysis were performed. Differentially expressed proteins were obtained from published proteomic studies and integrated with the transcriptomic results. To validate findings, a HF mouse model was generated and ferroptosis-related proteins were evaluated. Additionally, the effect of suppression of ferroptosis on hypoxia-induced ischemia model in HL-1 cardiomyocytes was assessed by knocking down Acyl-CoA synthetase long-chain family member 4 (ACSL4) using small interfering RNA (siRNA).Cross-analysis of differentially expressed genes (DEGs) in the GSE135055, GSE147236 and GSE161472 datasets revealed 224 up-regulated and 187 down-regulated potential genes which showed high enrichment in immune, inflammatory and metabolic pathways. Notably, four proteins, among them ACSL4, displayed consistent alterations at both the transcriptional and protein levels. In the HF mouse model, ACSL4 exhibited an elevation, whereas negative regulators of ferroptosis witnessed a decrement. Subsequently, knockdown of ACSL4 in a hypoxia-induced ischemic HL-1 cardiomyocyte cell model upregulated the expression of ferroptosis inhibitory protein and decreased the levels of reactive oxygen species (ROS), malondialdehyde (MDA)., and free iron and increased cell viability. Comprehensive multi-omics analysis revealed that the expression of the molecular target ACSL4 was increased in HF. Targeting ACSL4 to inhibit ferroptosis may represent a novel therapeutic strategy for HF treatment., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Polycyclic aromatic hydrocarbons (PAHs) are chemically stable pollutants that are poorly degraded by microorganisms in anoxic sediments. The anaerobic degradation pathway of PAHs such as phenanthrene starts with a carboxylation reaction forming phenanthroic acid. In this study, we identified and characterized the next enzyme in the pathway, the 2-phenanthroate:CoA ligase involved in the ATP-dependent formation of 2-phenanthroyl-CoA from cell-free extracts of the sulfate-reducing enrichment culture TRIP grown anaerobically with phenanthrene. The identified gene sequence indicated that 2-phenanthroate:CoA ligase belongs to the phenylacetate:CoA ligase-like enzyme family. Based on the sequence, we predict a two-domain structure of the 2-phenanthroate:CoA ligase with a typical large N-terminal and a smaller C-terminal domain. Partial purification of 2-phenanthroate:CoA ligase allowed us to identify the coding gene in the genome. 2-Phenanthroate:CoA ligase gene was heterologously expressed in Escherichia coli . Characterization of the 2-phenanthroate:CoA ligase was performed using the partially purified enzyme from cell-free extract and the purified recombinant enzyme. Testing all possible phenanthroic acid isomers as substrate for the ligase reaction showed that 2-phenanthroic acid is the preferred substrate and only 3-phenanthroic acid can be utilized to a minor extent. This also suggests that the product of the prior carboxylase reaction is 2-phenanthroic acid. 2-Phenanthroate:CoA ligase has an optimal activity at pH 7.5 and is oxygen-insensitive, analogous to other aryl-CoA ligases. In contrast to aryl-Coenzyme A ligases reported in the literature, which need Mg 2+ as cofactor, 2-phenanthroate:CoA ligase showed greatest activity with a combination of 5 mM MgCl 2 and 5 mM KCl. Furthermore, a substrate inhibition was observed at ATP concentrations above 1 mM and the enzyme was also active with ADP., Importance: Polycyclic aromatic hydrocarbons (PAHs) constitute a class of very toxic and persistent pollutants in the environment. However, the anaerobic degradation of three-ring PAHs such as phenanthrene is barely investigated. The initial degradation step starts with a carboxylation followed by a CoA‑thioesterification reaction performed by an aryl-CoA ligase. The formation of a CoA-thioester is an important step in the degradation pathway of aromatic compounds because the CoA-ester is needed for all downstream biochemical reactions in the pathway. Furthermore, we provide biochemical proof for the identification of the first genes for anaerobic phenanthrene degradation. Results presented here provide information about the biochemical and structural properties of the purified 2‑phenanthroate:CoA ligase and expand our knowledge of aryl-CoA ligases., Competing Interests: The authors declare no conflict of interest.

The 3-hydroxypropionate/4-hydroxybutyrate (3HP/4HB) cycle from ammonia-oxidizing Thaumarchaeota is currently considered the most energy-efficient aerobic carbon fixation pathway. The Nitrosopumilus maritimus 4-hydroxybutyryl-CoA synthetase (ADP-forming; Nmar&#95;0206) represents one of several enzymes from this cycle that exhibit increased efficiency over crenarchaeal counterparts. This enzyme reduces energy requirements on the cell, reflecting thaumarchaeal success in adapting to low-nutrient environments. Here we show the structure of Nmar&#95;0206 from Nitrosopumilus maritimus SCM1, which reveals a highly conserved interdomain linker loop between the CoA-binding and ATP-grasp domains. Phylogenetic analysis suggests the widespread prevalence of this loop and highlights both its underrepresentation within the PDB and structural importance within the (ATP-forming) acyl-CoA synthetase (ACD) superfamily. This linker is shown to have a possible influence on conserved interface interactions between domains, thereby influencing homodimer stability. These results provide a structural basis for the energy efficiency of this key enzyme in the modified 3HP/4HB cycle of Thaumarchaeota., (© 2024. The Author(s).)

The disease burden of non-alcoholic fatty liver disease (NAFLD) is increasing worldwide. Emerging evidence has revealed that silica nanoparticles (SiNPs) could disorder the liver lipid metabolism and cause hepatotoxicity, but the underlying mechanism remains unknown. The purpose of this study is to elucidate the molecular mechanism of hepatic lipid metabolism disorder caused by SiNPs, and to reveal the role of ferroptosis in SiNPs-induced hepatotoxicity. To explore the phenotypic changes in liver, the wild-type C57BL/6J mice were exposed to different doses of SiNPs (5, 10, 20 mg/kg·bw) with or without melatonin (20 mg/kg·bw). SiNPs accelerated hepatic oxidative stress and promoted pathological injury and lipid accumulation, resulting in NAFLD development. Melatonin significantly inhibited the oxidative damage caused by SiNPs. Then, the hepatocytes were treated with SiNPs, the ferroptosis inducer and inhibitor, respectively. In vitro, SiNPs (25 μg/mL) generated mitochondrial and intracellular Fe 2+ accumulation and lipid peroxidation repair ability impairment, decreased the activity of GPX4 through ACSL4/p38 MAPK signaling pathway, resulting in ferroptosis of hepatocytes. Notably, Erastin (the ferroptosis activator, 5 μM) increased the sensitivity of hepatocytes to ferroptosis. Ferrostatin-1 (Fer-1, the ferroptosis inhibitor, 5 μM) restored GPX4 activity and protected against deterioration of lipid hydroperoxides (LOOHs) to salvage SiNPs-induced cytotoxicity. Finally, the liver tissue conditional ACSL4 knockout (cKO) mice and ACSL4-KO hepatocytes were adopted to further identify the role of the ACSL4-mediated ferroptosis on SiNPs-induced NAFLD development. The results displayed ACSL4 knockout could down-regulate the lipid peroxidation and ferroptosis, ultimately rescuing the progression of NAFLD. In summary, our data indicated that ACSL4/p38 MAPK/GPX4-mediated ferroptosis was a novel and critical mechanism of SiNPs-induced NAFLD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

"Bubblegum" acyl-CoA synthetase (ACSBG1) is a pivotal player in lipid metabolism during mouse brain development, facilitating the activation of long-chain fatty acids (LCFA) and their incorporation into lipid species that are crucial for brain function. ACSBG1 converts LCFA into acyl-CoA derivatives, supporting vital metabolic processes. Fruit fly mutants lacking ACSBG1 exhibited neurodegeneration and had elevated levels of very long-chain fatty acids (VLCFA), characteristics of human X-linked adrenoleukodystrophy (XALD). To explore ACSBG1's function and potential as a therapeutic target in XALD, we created an ACSBG1 knockout (Acsbg1 -/- ) mouse and examined the effects on brain FA metabolism during development. Phenotypically, Acsbg1 -/- mice resembled wild type (w.t.) mice. ACSBG1 expression was found mainly in tissue affected pathologically in XALD, namely the brain, adrenal gland and testis. ACSBG1 depletion did not significantly reduce the total ACS enzyme activity in these tissue types. In adult mouse brain, ACSBG1 expression was highest in the cerebellum; the low levels detected during the first week of life dramatically increased thereafter. Unexpectedly, lower, rather than higher, saturated VLCFA levels were found in cerebella from Acsbg1 -/- vs. w.t. mice, especially after one week of age. Developmental changes in monounsaturated ω9 FA and polyunsaturated ω3 FA levels also differed between w.t. and Acsbg1 -/- mice. ACSBG1 deficiency impacted the developmental expression of several cerebellar FA metabolism enzymes, including those required for the synthesis of ω3 polyunsaturated FA, precursors of bioactive signaling molecules like eicosanoids and docosanoids. These changes in membrane lipid FA composition likely affect membrane fluidity and may thus influence the body's response to inflammation. We conclude that, despite compelling circumstantial evidence, it is unlikely that ACSBG1 directly contributes to the pathology of XALD, decreasing its potential as a therapeutic target. Instead, the effects of ACSBG1 knockout on processes regulated by eicosanoids and/or docosanoids should be further investigated.

Introduction: As a common malignancy, lung cancer has a relatively poor prognosis and a low survival rate. In recent years, ferroptosis, as an emerging filed, has great promise in the potential treatment of cancer. Brucea javanica oil (BJO) is often used to treat various cancers. Oleic acid (OA) is the main ingredient of BJO. In this study, we investigated the role and molecular mechanism of OA in lung cancer treatment by promoting ferroptosis., Methods: In this study, A549 cells and H1299 cells were used for in vitro experiments, and a CCK-8 test, scratch test, and MTT experiment were carried out. We examined reactive oxygen species (ROS), the JC-1 probe, glutathione (GSH) expression, lipid peroxidation, SDC4 mRNA levels, and ACSL4, SLC7A11, GPX4, and SDC4 protein levels., Results: The results showed that OA could inhibit the proliferation and migration of A549 cells and H1299 cells, SDC4 was a potential therapeutic target of OA against lung cancer, and OA treatment significantly inhibited the expression of SDC4 in A549 cells and H1299 cells. OA induces ferroptosis in A549 cells and H1299 cells, decreases GSH levels, increases lipid peroxidation levels, and decreases SDC4 mRNA expression; in addition, OA upregulates ACSL4 expression and decreases SLC7A11, GPX4, and SDC4 expression., Conclusion: This study confirmed that OA could inhibit SDC4 expression and promote the occurrence of ferroptosis in A549 cells and H1299 cells through the GPX4/ACSL4 pathway, providing an effective basis for the use of drugs targeting ferroptosis in lung cancer treatment., (© 2024 The Author(s). The Clinical Respiratory Journal published by John Wiley & Sons Ltd.)

Background: Lung cancer, on a global scale, leads to the most common cases of cancer mortalities. Novel therapeutic approaches are urgently needed to disrupt this lethal disease. The rapid development of tumor immunology combining breakthroughs involving fatty acid metabolism brings possibilities. Directing fatty acid metabolism is supposed to help discover potential prognostic biomarkers and treatment targets for lung cancer., Methods: Through searching the GSE140797 dataset, we identified genes related to fatty acid metabolism as well as fatty acid metabolism-related differentially expressed genes (DEGs). We applied various methods to ascertain the independent prognostic value of the DEGs. The methods we utilized entail prognostic analysis, differential expression analysis, as well as univariate and multivariate Cox regression analyses. The lasso Cox regression model was utilized in examining how DEGs correlate with the immune score, immune checkpoint, ferroptosis, methylation, and OCLR score. The expression levels of ACAT1 and ACSL3 in tissues derived from normal lung and lung adenocarcinoma (LUAD) tissues were compared by qRT-PCR., Results: In this study, ACSL3 and ACAT1 were identified as fatty acid metabolism-related genes utilizing independent prognostic value and as a result, the risk prognostic model was built using these factors. qRT-PCR results implied that ACSL3 and ACAT1 expressions were upregulated and downregulated, correspondingly in tumor tissues. Additional evaluations suggested that ACSL3 and ACAT1 were affirmed to be remarkably correlated with the immune score, methylation, immune checkpoint, OCLR score, and ferroptosis., Conclusions: ACSL3 and ACAT1 were effective prognostic biomarkers and potential immunotherapeutic targets in LUAD., (© 2024 The Author(s). The Clinical Respiratory Journal published by John Wiley & Sons Ltd.)

One of the most critical axes for cell fate determination is how cells respond to excessive reactive oxygen species (ROS)-oxidative stress. Extensive lipid peroxidation commits cells to death via a distinct cell death paradigm termed ferroptosis. However, the molecular mechanism regulating cellular fates to distinct ROS remains incompletely understood. Through siRNA against human receptor-interacting protein kinase (RIPK) family members, we found that RIPK4 is crucial for oxidative stress and ferroptotic death. Upon ROS induction, RIPK4 is rapidly activated, and the kinase activity of RIPK4 is indispensable to induce cell death. Specific ablation of RIPK4 in kidney proximal tubules protects mice from acute kidney injury induced by cisplatin and renal ischemia/reperfusion. RNA sequencing revealed the dramatically decreased expression of acyl-CoA synthetase medium-chain (ACSM) family members induced by cisplatin treatment which is compromised in RIPK4-deficient mice. Among these ACSM family members, suppression of ACSM1 strongly augments oxidative stress and ferroptotic cell death with induced expression of ACS long-chain family member 4, an important component for ferroptosis execution. Our lipidome analysis revealed that overexpression of ACSM1 leads to the accumulation of monounsaturated fatty acids, attenuation of polyunsaturated fatty acid (PUFAs) production, and thereby cellular resistance to ferroptosis. Hence, knockdown of ACSM1 resensitizes RIPK4 KO cells to oxidative stress and ferroptotic death. In conclusion, RIPK4 is a key player involved in oxidative stress and ferroptotic death, which is potentially important for a broad spectrum of human pathologies. The link between the RIPK4-ASCM1 axis to PUFAs and ferroptosis reveals a unique mechanism to oxidative stress-induced necrosis and ferroptosis., Competing Interests: Competing interests statement:The authors declare no competing interest.

Apicomplexa comprise important pathogenic parasitic protists that heavily depend on lipid acquisition to survive within their human host cells. Lipid synthesis relies on the incorporation of an essential combination of fatty acids (FAs) either generated by a metabolically adaptable de novo synthesis in the parasite or by scavenging from the host cell. The incorporation of FAs into membrane lipids depends on their obligate metabolic activation by specific enzyme groups, acyl-CoA synthetases (ACSs). Each ACS has its own specificity, so it can fulfill specific metabolic functions. Whilst such functionalities have been well studied in other eukaryotic models, their roles and importance in Apicomplexa are currently very limited, especially for Toxoplasma gondii. Here, we report the identification of seven putative ACSs encoded by the genome of T. gondii (TgACS), which localize to different sub-cellular compartments of the parasite, suggesting exclusive functions. We show that the perinuclear/cytoplasmic TgACS3 regulates the replication and growth of Toxoplasma tachyzoites. Conditional disruption of TgACS3 shows that the enzyme is required for parasite propagation and survival, especially under high host nutrient content. Lipidomic analysis of parasites lacking TgACS3 reveals its role in the activation of host-derived FAs that are used for i) parasite membrane phospholipid and ii) storage triacylglycerol (TAG) syntheses, allowing proper membrane biogenesis of parasite progenies. Altogether, our results reveal the role of TgACS3 as the bulk FA activator for membrane biogenesis allowing intracellular division and survival in T. gondii tachyzoites, further pointing to the importance of ACS and FA metabolism for the parasite., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Lung cancer (LC) is the leading cause of cancer-related mortality worldwide. Radiotherapy is the main component of LC treatment; however, its efficacy is often limited by radioresistance development, resulting in unsatisfactory clinical outcomes. Here, we found that LC radiosensitivity is up-regulated by decreased expression of long-chain acyl-CoA synthase 6 (ACSL6) after irradiation. Deletion of ACSL6 results in significant elevation of Friend leukemia integration 1 transcription factor (FLI1) and a marked decline of collagens (COLs). Blocking of ACSL6 impairs the tumor growth and upregulates FLI1, which reduces the levels of COLs and compromises irradiation-induced autophagy, leading to considerable therapeutic benefits during radiotherapy. Moreover, the direct interaction between ACSL6 and FLI1 and engagement between FLI1 and COLs indicates the involvement of the ACSL6-FLI1-COL axis. Finally, the potently adjusted autophagy flux reduces its otherwise contributive capability in surviving irradiation stress and leads to satisfactory radiosensitization for LC radiotherapy. These results demonstrate that enhanced ACSL6 expression promotes the aggressive performance of irradiated LC through increased FLI1-COL-mediated autophagy flux. Thus, the ACSL6-FLI1-Col-autophagy axis may be targeted to enhance the radiosensitivity of LC and improve the management of LC in radiotherapy., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Prostate cancer (PCa) is one of the most common cancers affecting the health of men worldwide. Castration-resistant prostate cancer (CRPC), the advanced and refractory phase of prostate cancer, has multiple mechanisms of resistance to androgen deprivation therapy (ADT) such as AR mutations, aberrant androgen synthase, and abnormal expression of AR-related genes. Based on the research of the AR pathway, new drugs for the treatment of CRPC have been developed in clinical practice, such as Abiraterone and enzalutamide. However, many areas in this pathway are still worth exploring. In this study, single-cell sequencing analysis was utilized to scrutinize significant genes in the androgen receptor (AR) pathway related to CRPC. Our analysis of single-cell sequencing combined with bulk-cell sequencing revealed a substantial downregulation of AR-regulated AFF3 in CRPC. Overexpression of AFF3 restricted the proliferation and migration of prostate cancer cells whilst also increasing their sensitivity towards enzalutamide, while knockdown of AFF3 had the opposite effect. To elucidate the mechanism of tumor inhibition by AFF3, we applied GSVA and GSEA to investigate the metabolic pathways related to AFF3 and revealed that AFF3 had an impact on fatty acids metabolism and ferroptosis through the regulation of ACSL4 protein expression. Based on correlation analysis and flow cytometry, we can speculate that AFF3 can impact the sensitivity of the CRPC cell lines to the ferroptosis inducer (RSL3) by regulating ACSL4. Therefore, our findings may provide new insights into the mechanisms of drug resistance in CRPC, and AFF3 may serve as a novel prognostic biomarker in prostate cancer., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Valproic acid (VPA), a common antiepileptic drug, can cause liver steatosis after long-term therapy. However, an impact of ferroptosis on VPA-induced liver steatosis has not been investigated. In the study, treatment with VPA promoted ferroptosis in the livers of mice by elevating ferrous iron (Fe 2+ ) levels derived from the increased absorption by transferrin receptor 1 (TFR1) and the decreased storage by ferritin (FTH1 and FTL), disrupting the redox balance via reduced levels of solute carrier family 7 member 11 (SLC7A11), glutathione (GSH), and glutathione peroxidase 4 (GPX4), and augmenting acyl-CoA synthetase long-chain family member 4 (ACSL4) -mediated lipid peroxide generation, accompanied by enhanced liver steatosis. All the changes were significantly reversed by co-treatment with an iron-chelating agent, deferoxamine mesylate (DFO) and a ferroptosis inhibitor, ferrostatin-1 (Fer-1). Similarly, the increases in Fe 2+ , TFR1, and ACSL4 levels, as well as the decreases in GSH, GPX4, and ferroportin (FPN) levels, were detected in VPA-treated HepG2 cells. These changes were also attenuated after co-treatment with Fer-1. It demonstrates that ferroptosis promotes VPA-induced liver steatosis through iron overload, inhibition of the GSH-GPX4 axis, and upregulation of ACSL4. It offers a potential therapy targeting ferroptosis for patients with liver steatosis following VPA treatment., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Whether stem-cell-like cancer cells avert ferroptosis to mediate therapy resistance remains unclear. In this study, using a soft fibrin gel culture system, we found that tumor-repopulating cells (TRCs) with stem-cell-like cancer cell characteristics resist chemotherapy and radiotherapy by decreasing ferroptosis sensitivity. Mechanistically, through quantitative mass spectrometry and lipidomic analysis, we determined that mitochondria metabolic kinase PCK2 phosphorylates and activates ACSL4 to drive ferroptosis-associated phospholipid remodeling. TRCs downregulate the PCK2 expression to confer themselves on a structural ferroptosis-resistant state. Notably, in addition to confirming the role of PCK2-pACSL4(T679) in multiple preclinical models, we discovered that higher PCK2 and pACSL4(T679) levels are correlated with better response to chemotherapy and radiotherapy as well as lower distant metastasis in nasopharyngeal carcinoma cohorts., (© 2024. The Author(s).)

Long-chain acyl-CoA synthetases (LACSs), belonging to the acyl-activating enzyme superfamily, play crucial roles in lipid biosynthesis and fatty acid catabolism. Here, we identified 11 LACS genes in the tomato reference genome, and these genes were clustered into six subfamilies. Gene structure and conserved motif analyses indicated that LACSs from the same subfamily shared conserved gene and protein structures. Expression analysis revealed that SlLACS1 was highly expressed in the outer epidermis of tomato fruits and leaves. Subcellular localization assay results showed that SlLACS1 was located in the endoplasmic reticulum. Compared with wild-type plants, the wax content on leaves and fruits decreased by 22.5-34.2 % in SlLACS1 knockout lines, confirming that SlLACS1 was involved in wax biosynthesis in both leaves and fruits. Water loss, chlorophyll extraction, water-deficit, and toluidine blue assays suggested that cuticle permeability was elevated in SlLACS1 knockout lines, resulting in reduction in both drought stress resistance and fruit shelf-life. Overall, our analysis of the LACSs in tomato, coupled with investigations of SlLACS1 function, yielded a deeper understanding of the evolutionary patterns of LACS members and revealed the involvement of SlLACS1 in wax accumulation contribute to drought resistance and extended fruit shelf-life in tomato., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Acute lung injury (ALI) is a serious disorder characterized by the release of pro-inflammatory cytokines and cascade activation of macrophages. Ferroptosis, a form of iron-dependent cell death triggered by intracellular phospholipid peroxidation, has been implicated as an internal mechanism underlying ALI. In this study, we investigated the effects of m 6 A demethylase fat mass and obesity-associated protein (FTO) on the inhibition of macrophage ferroptosis in ALI. Using a mouse model of lipopolysaccharide (LPS)-induced ALI, we observed the induction of ferroptosis and its co-localization with the macrophage marker F4/80, suggesting that ferroptosis might be induced in macrophages. Ferroptosis was promoted during LPS-induced inflammation in macrophages in vitro, and the inflammation was counteracted by the ferroptosis inhibitor ferrostatin-1 (fer-1). Given that FTO showed lower expression levels in the lung tissue of mice with ALI and inflammatory macrophages, we further dissected the regulatory capacity of FTO in ferroptosis. The results demonstrated that FTO alleviated macrophage inflammation by inhibiting ferroptosis. Mechanistically, FTO decreased the stability of ACSL4 mRNA via YTHDF1, subsequently inhibiting ferroptosis and inflammation by interrupting polyunsaturated fatty acid consumption. Moreover, FTO downregulated the synthesis and secretion of prostaglandin E 2 , thereby reducing ferroptosis and inflammation. In vivo, the FTO inhibitor FB23-2 aggravated lung injury, the inflammatory response, and ferroptosis in mice with ALI; however, fer-1 therapy mitigated these effects. Overall, our findings revealed that FTO may function as an inhibitor of the inflammatory response driven by ferroptosis, emphasizing its potential as a target for ALI treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Hepatocellular carcinoma (HCC) is the most common primary liver cancer, with high incidence and mortality worldwide. Despite diagnostic and therapeutic advancements, HCC remains poorly responsive to treatment, with a poor prognosis. Understanding the molecular mechanisms driving HCC is crucial for developing effective therapies. Emerging evidence indicates that dysregulated fatty acid metabolism contributes to HCC. Acyl-CoA medium-chain synthetase 5 (ACSM5), involved in fatty acid metabolism, is down-regulated in HCC; however, its role is not well understood. This study was used to analyze ACSM5 expression in HCC patient samples and cell lines. The newly established ACSM5-overexpressing HCC cell lines, Huh7-ACSM5 and Hepa1-6-ACSM5, were used to investigate the effects and regulatory mechanisms of ACSM5. The results showed that ACSM5 was significantly down-regulated in HCC tumor tissues compared with non-tumor tissues. ACSM5 expression was regulated by DNA methylation, with a DNA methyltransferase 1 (DNMT1) inhibitor effectively increasing ACSM5 expression and reducing promoter region methylation. Overexpression of ACSM5 in Huh7 cells reduced fatty acid accumulation, decreased cell proliferation, migration, and invasion in vitro, and inhibited tumor growth in mouse xenografts. Furthermore, ACSM5 overexpression also decreased STAT3 phosphorylation, subsequently affecting downstream cytokine TGFB and FGF12 mRNA levels. These findings suggest that ACSM5 down-regulation contributes to HCC progression, providing insights into its oncogenic role and highlighting its potential as a biomarker and therapeutic target for HCC., Competing Interests: Disclosure Statement None declared., (Copyright © 2024 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Chemotherapy including platinum-based drugs are a possible strategy to enhance the immune response in advanced melanoma patients who are resistant to immune checkpoint blockade (ICB) therapy. However, the immune-boosting effects of these drugs are a subject of controversy, and their impact on the tumor microenvironment are poorly understood. In this study, we discovered that lipid peroxidation (LPO) promotes the formation of lipid rafts in the membrane, which mediated by Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4) impairs the sensitivity of melanoma cells to platinum-based drugs. This reduction primarily occurs through the inhibition of immunogenic ferroptosis and pyroptosis by reducing cell membrane pore formation. By disrupting ACSL4-mediaged lipid rafts via the removal of membrane cholesterol, we promoted immunogenic cell death, transformed the immunosuppressive environment, and improved the antitumor effectiveness of platinum-based drugs and immune response. This disruption also helped reverse the decrease in CD8 + T cells while maintaining their ability to secrete cytokines. Our results reveal that ACSL4-dependent LPO is a key regulator of lipid rafts formation and antitumor immunity, and that disrupting lipid rafts has the potential to enhance platinum-based drug-induced immunogenic ferroptosis and pyroptosis in melanoma. This novel strategy may augment the antitumor immunity of platinum-based therapy and further complement ICB therapy., (© 2024. The Author(s).)

Pressure overload-induced cardiac hypertrophy is a common cause of heart failure (HF), and emerging evidence suggests that excessive oxidized lipids have a detrimental effect on cardiomyocytes. However, the key regulator of lipid toxicity in cardiomyocytes during this pathological process remains unknown. Here, we used lipidomics profiling and RNA-seq analysis and found that phosphatidylethanolamines (PEs) and Acsl4 expression are significantly increased in mice with transverse aortic constriction (TAC)-induced HF compared to sham-operated mice. In addition, we found that overexpressing Acsl4 in cardiomyocytes exacerbates pressure overload‒induced cardiac dysfunction via ferroptosis. Notably, both pharmacological inhibition and genetic deletion of Acsl4 significantly reduced left ventricular chamber size and improved cardiac function in mice with TAC-induced HF. Moreover, silencing Acsl4 expression in cultured neonatal rat ventricular myocytes was sufficient to inhibit hypertrophic stimulus‒induced cell growth. Mechanistically, we found that Acsl4-dependent ferroptosis activates the pyroptotic signaling pathway, which leads to increased production of the proinflammatory cytokine IL-1β, and neutralizing IL-1β improved cardiac function in Acsl4 transgenic mice following TAC. These results indicate that ACSL4 plays an essential role in the heart during pressure overload‒induced cardiac remodeling via ferroptosis-induced pyroptotic signaling. Together, these findings provide compelling evidence that targeting the ACSL4-ferroptosis-pyroptotic signaling cascade may provide a promising therapeutic strategy for preventing heart failure., (© 2024. The Author(s).)

Background: Ferroptosis, a novel iron-ion-dependent metabolic cell death mode with lipid peroxides as the main driving substrate, plays an irreplaceable role in the development and preventive treatment of hepatocellular carcinoma. Curcumin has potent pharmacological anti-tumor effects., Aim of the Study: We aimed to evaluate the ex vivo and in vivo cancer inhibitory activity of curcumin and its specific mechanism of action., Materials and Methods: We used the hepatocellular carcinoma cell lines HepG2 and SMMC7721 to assess the direct inhibition of hepatocellular carcinoma proliferation by curcumin in vitro and a tumor xenograft model to evaluate the in vivo cancer inhibitory effect of curcumin., Results: In this study, we found that ferroptosis's inhibitors specifically reversed the curcumin-induced cell death pattern in HCC. After curcumin intervention, there was a substantial increase in MDA levels and iron ion levels, and a decrease in intracellular GSH levels. Meanwhile, the expression of GPX4 and SLC7A11 was significantly reduced at the protein levels, while ACSL4 and PTGS2 expression was significantly increased., Conclusions: This study showed that curcumin significantly decreased the proliferation of HCC cells and significantly increased the sensitivity of ferroptosis. These results suggest that ACSL4 is a viable target for curcumin-induced ferroptosis in treating HCC., (© 2024. The Author(s).)

Ferroptosis, a key factor in tumor progression, is poorly understood at the molecular level. This study investigates how ELK4 and CHMP6 regulate skin cutaneous melanoma (SKCM) cell proliferation and ferroptosis. Analysis of TCGA data reveals high expression of ELK4 and CHMP6 in SKCM. Overexpression of ELK4 or CHMP6 enhances cell proliferation, invasion, and migration while reducing ROS and Fe2 + levels. It also increases GPX4 and xCT expression and decreases ACSL4 levels in SKCM cells. The opposite effects are observed with ELK4 or CHMP6 knockdown. ELK4 binds to the CHMP6 promoter, promoting CHMP6 transcription. Knockdown of CHMP6 reverses the oncogenic effects of ELK4 overexpression. In conclusion, ELK4 enhances proliferation, invasion, and migration while inhibiting ferroptosis in SKCM cells by upregulating CHMP6 transcription. This study sheds light on the intricate mechanisms involved in SKCM progression and identifies potential therapeutic targets in melanoma treatment., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Aberrant activation of IL-18 signaling regulates tumor immune evasion and progression. However, the underlying mechanism remains unclear. Here, we report that long-chain acyl-CoA synthase 6 (ACSL6) is highly expressed in liver cancer and correlated with poor prognosis. ACSL6 promotes tumor growth, metastasis, and immune evasion mediated by IL-18, independent of its metabolic enzyme activity. Mechanistically, upon IL-18 stimulation, ACSL6 is phosphorylated by ERK2 at S674 and recruits IL-18RAP to interact with IL-18R1, thereby reinforcing the IL-18R1-IL-18RAP heterodimer and triggering NF-κB-dependent gene expression to facilitate tumor development. Furthermore, the up-regulation of CXCL1 and CXCL5 by ACSL6 promotes tumor-associated neutrophil and tumor-associated macrophage recruitment, thereby inhibiting cytotoxic CD8 + T cell infiltration. Ablation or S674A mutation of ACSL6 potentiated anti-PD-1 therapeutic efficacy by increasing the effector activity of intertumoral CD8 + T cells. We revealed that ACSL6 is a potential adaptor that activates IL-18-NF-κB axis-mediated tumor immune evasion and provides valuable insights for developing effective immunotherapy strategies for cancer.

Hemolysis drives susceptibility to lung injury and predicts poor outcomes in diseases, such as malaria and sickle cell disease (SCD). However, the underlying pathological mechanism remains elusive. Here, we report that major facilitator superfamily domain containing 7 C (MFSD7C) protects the lung from hemolytic-induced damage by preventing ferroptosis. Mechanistically, MFSD7C deficiency in HuLEC-5A cells leads to mitochondrial dysfunction, lipid remodeling and dysregulation of ACSL4 and GPX4, thereby enhancing lipid peroxidation and promoting ferroptosis. Furthermore, systemic administration of MFSD7C mRNA-loaded nanoparticles effectively prevents lung injury in hemolytic mice, such as HbSS-Townes mice and PHZ-challenged 7 C -/- mice. These findings present the detailed link between hemolytic complications and ferroptosis, providing potential therapeutic targets for patients with hemolytic disorders., (© 2024. The Author(s).)

The acetogen Acetobacterium woodii couples caffeate reduction with ferredoxin reduction and NADH oxidation via electron bifurcation, providing additional reduced ferredoxin for energy conservation and cell synthesis. Caffeate is first activated by an acyl-CoA synthetase (CarB), which ligates CoA to caffeate at the expense of ATP. After caffeoyl-CoA is reduced to hydrocaffeoyl-CoA, the CoA moiety in hydrocaffeoyl-CoA could be recycled for caffeoyl-CoA synthesis by an ATP-independent CoA transferase (CarA) to save energy. However, given that CarA and CarB are co-expressed, it was not well understood how ATP could be saved when both two competitive pathways of caffeate activation are present. Here, we reported a dual feedback inhibition of the CarB-mediated caffeate activation by the intermediate hydrocaffeoyl-CoA and the end-product hydrocaffeate. As the product of CarA, hydrocaffeate inhibited CarB-mediated caffeate activation by serving as another substrate of CarB with hydrocaffeoyl-CoA produced. It effectively competed with caffeate even at a concentration much lower than caffeate. Hydrocaffeoyl-CoA formed in this process can also inhibit CarB-mediated caffeate activation. Thus, the dual feedback inhibition of CarB, together with the faster kinetics of CarA, makes the ATP-independent CarA-mediated CoA loop the major route for caffeoyl-CoA synthesis, further saving ATP in the caffeate-dependent electron-bifurcating pathway. A genetic architecture similar to carABC has been found in other anaerobic bacteria, suggesting that the feedback inhibition of acyl-CoA ligases could be a widely employed strategy for ATP conservation in those pathways requiring substrate activation by CoA., Importance: This study reports a dual feedback inhibition of caffeoyl-CoA synthetase by two downstream products, hydrocaffeate and hydrocaffeoyl-CoA. It elucidates how such dual feedback inhibition suppresses ATP-dependent caffeoyl-CoA synthesis, hence making the ATP-independent route the main pathway of caffeate activation. This newly discovered mechanism contributes to our current understanding of ATP conservation during the caffeate-dependent electron-bifurcating pathway in the ecologically important acetogen Acetobacterium woodii . Bioinformatic mining of microbial genomes revealed contiguous genes homologous to carABC within the genomes of other anaerobes from various environments, suggesting this mechanism may be widely used in other CoA-dependent electron-bifurcating pathways., Competing Interests: The authors declare no conflict of interest.

Ethnopharmacological Relevance: Acute ischemic stroke (AIS) is a prominent cause of disability and mortality around the world. Achyranthes bidentata Blume, a regularly prescribed traditional Chinese herb, plays a significant role in traditional Chinese stroke therapy due to its ability to promote blood circulation and remove stasis. Ecdysterone (EDS) is one of the key active components in Achyranthes bidentata Blume, which exhibits antioxidant and anti-cerebral hypoxia properties. However, whether EDS improves AIS and the mechanism of action of AIS is still unclear., Aim of the Study: The objective of this study was to observe whether EDS ameliorates oxidative damage caused by AIS by inhibiting ferroptosis in neurons via ACSL4., Materials and Methods: In vivo, the Middle cerebral artery occlusion (MCAO) rat model was established for research. After treatment with EDS, Neurologic score, TTC, HE and FJC staining were performed, followed by measurements of oxidative stress-related indicators, the content of Fe 2+ , iron deposition levels and expression of ACSL4, NCOA4 and FTH1 in brain tissue. In vitro, oxygen-glucose deprivation and reperfusion (OGD/R) cell model was established. After treatment with EDS, cell viability, oxidative stress-related indicators, the content of Fe 2+ and expression of ACSL4, NCOA4 and FTH1 were detected. In addition, the overexpression of ACSL4 and CETSA technology further elucidated that EDS improves AIS through ACSL4., Results: The results showed that the treatment of EDS could improve the oxidative damage of MCAO rats by inhibiting ferroptosis, and then improve AIS. Importantly, EDS inhibited ferroptosis via ACSL4, thereby inhibiting oxidative stress in MCAO rats or OGD/R-induced PC12 cells., Conclusions: These results provide evidence that EDS ameliorates oxidative damage caused by AIS by inhibiting ferroptosis via ACSL4, and provide new insights into the potential use of EDS as an effective drug development candidate for AIS., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

LHPP, a novel, recognized tumor suppressor, exerts a critical influence on the regulation of tumor cell proliferation and survival by modulating various signaling pathways with its phosphatase activity. Here, we unveil a robust correlation between reduced LHPP expression and adverse prognosis in prostate cancer. We demonstrate that LHPP interacts with AKT, thereby dampening AKT phosphorylation and subsequently inhibiting ACSL4 phosphorylation at the T624 site. This interaction impedes phosphorylation-dependent ubiquitination, thwarting SKP2 from recognizing and binding to ACSL4 at the K621 site. As a result, ACSL4 is spared from lysosomal degradation, leading to its accumulation and the promotion of lipid peroxidation, and ferroptosis. Moreover, our findings reveal that Panobinostat, a potent histone-deacetylase inhibitor, intricately regulates LHPP expression at multiple levels through the inhibition of HDAC3. This complex modulation enhances the ferroptosis pathway, offering a novel mechanism for curtailing the growth of prostate tumors and highlighting its significant translational potential for clinical application., (© 2024. The Author(s).)

This study aims to investigate the role of ferroptosis, an iron-dependent form of regulated cell death, in male infertility. The motivation behind this research stems from the increasing recognition of oxidative stress and iron metabolism dysregulation as critical factors in male reproductive health. In this study, 28 infertile patients (grouped by the presence of urogenital infections or varicocele) and 19 fertile men were selected. Spermiograms were performed by light microscopy (WHO, 2021). Testosterone, ferritin, transferrin-bound iron, transferrin, and F 2 -isoprostanes (F 2 -IsoPs) were detected in seminal plasma. Glutathione peroxidase 4 (GPX4) and acyl coenzyme A synthetase long chain family member 4 (ACSL4) were also assessed in sperm cells using enzyme-linked immunosorbent assays (ELISA). All the variables were correlated (statistically significant Spearman's rank correlations) in the whole population, and then the comparison between variables of the different groups of men were carried out. Seminal ferritin and transferrin positively correlated with seminal F 2 -IsoPs, which had positive correlations with ACSL4 detected in sperm cells. Ferritin and ACSL4 negatively correlated with the seminal parameters. No correlation was detected for GPX4. Comparing the variables in the three examined groups, elevated levels of ACSL4 were observed in infertile patients with urogenital infections and varicocele; GPX4 levels were similar in the three groups. These results suggested a mechanism of ferroptosis, identified by increased ACSL4 levels and the occurrence of lipid peroxidation. Such events appear to be GPX4-independent in reproductive pathologies such as varicocele and urogenital infections.

Beige fat activation involves a fuel switch to fatty acid oxidation following chronic cold adaptation. Mitochondrial acyl-CoA synthetase long-chain family member 1 (ACSL1) localizes in the mitochondria and plays a key role in fatty acid oxidation; however, the regulatory mechanism of the subcellular localization remains poorly understood. Here, we identify an endosomal trafficking component sortilin (encoded by Sort1) in adipose tissues that shows dynamic expression during beige fat activation and facilitates the translocation of ACSL1 from the mitochondria to the endolysosomal pathway for degradation. Depletion of sortilin in adipocytes results in an increase of mitochondrial ACSL1 and the activation of AMPK/PGC1α signaling, thereby activating beige fat and preventing high-fat diet (HFD)-induced obesity and insulin resistance. Collectively, our findings indicate that sortilin controls adipose tissue fatty acid oxidation by substrate fuel selection during beige fat activation and provides a potential targeted approach for the treatment of metabolic diseases., (© 2024. The Author(s).)

Per and polyfluoroalkyl substances (PFAS) are a large family of anthropogenic fluorinated chemicals of increasing environmental concern. Over recent years, numerous microbial communities have been found to be capable of metabolizing some polyfluoroalkyl substances, generating a range of low-molecular-weight PFAS metabolites. One proposed pathway for the microbial breakdown of fluorinated carboxylates includes β-oxidation, this pathway is initiated by the formation of a CoA adduct. However, until recently no PFAS-CoA adducts had been reported. In a previous study, we were able to use a bacterial medium-chain acyl-CoA synthetase (mACS) to form CoA adducts of fluorinated adducts of propanoic acid and pentanoic acid but were not able to detect any products of fluorinated hexanoic acid analogues. Herein, we expressed and purified a long-chain acyl-CoA synthetase (lACS) and a A461K variant of mACS from the soil bacterium Gordonia sp. strain NB4-1Y and performed an analysis of substrate scope and enzyme kinetics using fluorinated and nonfluorinated carboxylates. We determined that lACS can catalyze the formation of CoA adducts of 1:5 fluorotelomer carboxylic acid (FTCA), 2:4 FTCA and 3:3 FTCA, albeit with generally low turnover rates (<0.02 s -1 ) compared with the nonfluorinated hexanoic acid (5.39 s -1 ). In addition, the A461K variant was found to have an 8-fold increase in selectivity toward hexanoic acid compared with wild-type mACS, suggesting that Ala-461 has a mechanistic role in selectivity toward substrate chain length. This provides further evidence to validate the proposed activation step involving the formation of CoA adducts in the enzymatic breakdown of PFAS.

Background: Renal ischaemia‒reperfusion injury (IRI) is the primary cause of acute kidney injury (AKI). To date, effective therapies for delaying renal IRI and postponing patient survival remain absent. Ankyrin repeat domain 1 (ANKRD1) has been implicated in some pathophysiologic processes, but its role in renal IRI has not been explored., Methods: The mouse model of IRI-AKI and in vitro model were utilised to investigate the role of ANKRD1. Immunoprecipitation-mass spectrometry was performed to identify potential ANKRD1-interacting proteins. Protein‒protein interactions and protein ubiquitination were examined using immunoprecipitation and proximity ligation assay and immunoblotting, respectively. Cell viability, damage and lipid peroxidation were evaluated using biochemical and cellular techniques., Results: First, we unveiled that ANKRD1 were significantly elevated in renal IRI models. Global knockdown of ANKRD1 in all cell types of mouse kidney by recombinant adeno-associated virus (rAAV9)-mitigated ischaemia/reperfusion-induced renal damage and failure. Silencing ANKRD1 enhanced cell viability and alleviated cell damage in human renal proximal tubule cells exposed to hypoxia reoxygenation or hydrogen peroxide, while ANKRD1 overexpression had the opposite effect. Second, we discovered that ANKRD1's detrimental function during renal IRI involves promoting lipid peroxidation and ferroptosis by directly binding to and decreasing levels of acyl-coenzyme A synthetase long-chain family member 3 (ACSL3), a key protein in lipid metabolism. Furthermore, attenuating ACSL3 in vivo through pharmaceutical approach and in vitro via RNA interference mitigated the anti-ferroptotic effect of ANKRD1 knockdown. Finally, we showed ANKRD1 facilitated post-translational degradation of ACSL3 by modulating E3 ligase tripartite motif containing 25 (TRIM25) to catalyse K63-linked ubiquitination of ACSL3, thereby amplifying lipid peroxidation and ferroptosis, exacerbating renal injury., Conclusions: Our study revealed a previously unknown function of ANKRD1 in renal IRI. By driving ACSL3 ubiquitination and degradation, ANKRD1 aggravates ferroptosis and ultimately exacerbates IRI-AKI, underlining ANKRD1's potential as a therapeutic target for kidney IRI., Key Points/highlights: Ankyrin repeat domain 1 (ANKRD1) is rapidly activated in renal ischaemia‒reperfusion injury (IRI) models in vivo and in vitro. ANKRD1 knockdown mitigates kidney damage and preserves renal function. Ferroptosis contributes to the deteriorating function of ANKRD1 in renal IRI. ANKRD1 promotes acyl-coenzyme A synthetase long-chain family member 3 (ACSL3) degradation via the ubiquitin‒proteasome pathway. The E3 ligase tripartite motif containing 25 (TRIM25) is responsible for ANKRD1-mediated ubiquitination of ACSL3., (© 2024 The Author(s). Clinical and Translational Medicine published by John Wiley & Sons Australia, Ltd on behalf of Shanghai Institute of Clinical Bioinformatics.)