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Background: Non‐small‐cell lung cancer (NSCLC) often presents at later stages, typically associated with poor prognosis. Autophagy genes play a role in the progression of tumors. This study investigated the clinical relevance, prognostic value, and biological significance of RBBP4 in NSCLC. Methods: We assessed RBBP4 expression using the GSE30219 and TCGA NSCLC datasets and NSCLC cells, exploring its links with clinical outcomes, tumor immunity, and autophagy genes through bioinformatics analysis after transcriptome sequencing of RBBP4‐knockdown and control PC9 cells. We identified differentially expressed genes (DEGs) and conducted Gene Ontology, Kyoto Encyclopedia of Genes and Genomes pathway enrichment, and protein–protein interaction network analyses. The significance of autophagy‐related DEGs was evaluated for diagnosis and prognosis using the GSE30219 dataset. Experiments both in vivo and in vitro explored the biological mechanisms behind RBBP4‐mediated autophagic cell death in NSCLC. Results: RBBP4 overexpression in NSCLC correlates with a poorer prognosis. Eighteen types of immune cell were significantly enriched in cultures that had low RBBP4 expression compared high expression. DEGs associated with RBBP4 are enriched in autophagy pathways. Transcriptomic profiling of the PC9 cell line identified autophagy‐related DEGs associated with RBBP4 that exhibited differential expression in NSCLC, suggesting prognostic applications. In vitro experiments demonstrated that RBBP4 knockdown induced autophagy and apoptosis in PC9 cells, promoting cell death, which was inhibited by 3‐MA. In vivo, targeted siRNA against RBBP4 significantly reduced tumor development in PC9 cell‐injected nude mice, elevating autophagy‐related protein levels and inducing apoptosis and necrosis in tumor tissues. Conclusion: In NSCLC, RBBP4 upregulation correlates with poor prognosis and altered immunity. Its knockdown induces autophagic cell death in NSCLC cells. These results indicate RBBP4 as a potential NSCLC diagnostic marker and its autophagy modulation as a prospective therapeutic target. [ABSTRACT FROM AUTHOR]

Background: β‐Glucan from Lentinus edodes (LNT), an edible mushroom, possesses strong anticancer activity. However, the therapeutic effects of LNT during the occurrence and progression of breast cancer and their underlying molecular mechanisms have not been elucidated. Methods: Mouse mammary tumor virus‐polyoma middle tumor‐antigen (MMTV‐PyMT) transgenic mice were used as a breast cancer mouse model. Hematoxylin and eosin, immunohistochemical, and immunofluorescence staining were performed for histopathological analysis. Moreover, we developed an inflammatory cell model using tumor necrosis factor‐α (TNF‐α). Macrophage polarization was assessed using western blot analysis and immunofluorescence. Results: Orphan nuclear receptor 77 (Nur77) and sequestosome‐1 (p62) were highly expressed and positively correlated with each other in breast cancer tissues. LNT significantly inhibited tumor growth, ameliorated inflammatory cell infiltration, and induced tumor cell apoptosis in PyMT transgenic mice. Moreover, LNT attenuated the ability of tumors to metastasize to lung tissue. Mechanistically, LNT treatment restrained macrophage polarization from M1 to M2 phenotype and promoted autophagic cell death by inhibiting Nur77 expression, AKT/mTOR signaling, and inflammatory signals in breast tumor cells. However, LNT did not exhibit a direct pro‐autophagic effect on tumor cell death, except for its inhibitory effect on Nur77 expression. LNT‐mediated autophagic tumor cell death depends on M1 macrophage polarization. In in vitro experiments, LNT inhibited the upregulation of p62, autophagy activation, and inflammatory signaling pathways in Nur77 cells. Conclusion: LNT inhibited macrophage M2 polarization and subsequently blocked the AKT/mTOR and inflammatory signaling axes in breast cancer cells, thereby promoting autophagic tumor cell death. Thus, LNT may be a promising therapeutic strategy for breast cancer. [ABSTRACT FROM AUTHOR]

The detection of high levels of microplastics in indoor and outdoor air has increased concerns regarding its toxic effects on the respiratory system. They are not easily degradable and can be deposited deep in the lungs. Although several studies have reported inhalation toxicities of microplastics, they are still controversial due to a lack of evidence. Herein, we evaluated the inhalation toxicities of three differently charged polystyrene microplastics (PS‐MPs), the most abundant microplastics in the air. Cytotoxicity and ROS generation were evaluated using WST‐1 and DCF‐DA assays, respectively. To evaluate the toxic effects on the lung, inflammatory responses were analyzed after repeated exposure to the PS‐MPs through intratracheal instillation. To explore the mechanism of toxicity, autophagy and ER stress‐associated proteins were analyzed. Only the positively charged PS‐MPs (NH2‐PS‐MPs) showed cytotoxicity and increased ROS generation in BEAS‐2B cells. Similarly, only NH2‐PS‐MPs significantly increased the expression and secretion of the pro‐inflammatory cytokine IL‐β in the animal experiments. The expression of ER stress proteins indicated that NH2‐PS‐MPs increased ER stress via PERK‐EIF2α and ATF4‐CHOP pathways. Moreover, accumulation of NH2‐PS‐MPs in lysosomes and deformity of the nucleus were observed in BEAS‐2B cells with autophagy induction. Taken together, our results demonstrated that NH2‐PS‐MPs induced autophagic cell death in bronchial epithelial cells, leading to inflammatory responses in the lungs. These results suggest that repeated inhalation of microplastics can result in inflammatory responses in the lung through cellular damage of lung epithelial cells, and that inhalation microplastics should be monitored to reduce inhalation health risks. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus (T2DM) is a growing worldwide epidemic and is characterized by progressive pancreatic β‐cell dysfunction and insulin resistance. Tripartite motif protein 32 (TRIM32) belongs to the TRIM family protein and has been shown to be involve in insulin resistance in skeletal muscle and the liver. However, the effect of TRIM32 on pancreatic β‐cell dysfunction and its mechanism remains unknown. In the current study, we found that serum TRIM32 concentrations of T2DM in patients were significantly elevated compared to those in healthy controls, which indicated that TRIM32 might be used as a diagnostic biomarker in T2DM patients. In INS‐1 cells, exposure to high glucose (HG) conditions caused a significant elevation in TRIM32 expression and TRIM32 was located in the nucleus. Overexpression of TRIM32 in INS‐1 cells exacerbated the effects of HG‐induced autophagy and impaired insulin secretion. In contrast, the silencing of TRIM32 produced the opposite effect. Furthermore, TRIM32 overexpression decreased the phosphorylation levels of Akt and mTOR under HG conditions. However, the activation of Akt/mTOR by MHY1485 reversed the effects of TRIM32 on HG‐treated INS‐1 cells. Collectively, the present results suggested that TRIM32 participates in the development of T2DM by modulating autophagic cell death and insulin secretion, which might occur through the Akt/mTOR pathway. Thus, TRIM32 might be a promising target in T2DM therapy. [ABSTRACT FROM AUTHOR]

Various clinical and experimental findings have revealed the causal relationship between autophagy failure and oncogenesis, and several mechanisms have been suggested to explain this relationship. We recently proposed two additional mechanisms: centrosome number dysregulation and the failure of autophagic cell death. Here, we detail the mechanical relationship between autophagy failure and oncogenesis. [ABSTRACT FROM AUTHOR]

Objectives: Cryptococcus heimaeyensis S20 is found in Antarctica and can produce exopolysaccharides (CHEPS). Here, we explore the anti‐tumour effects of CHEPS on non‐small cell lung cancer (NSCLC). Materials and methods: Cell viability was assessed by CCK8 and colony formation assays. Flow cytometry was used to analyse the cell cycle, cell apoptosis and reactive oxygen species (ROS). Cell autophagy was detected by EGFP‐LC3 puncta assay, Lyso‐Tracker Red staining and transmission electron microscopy. mRNA and protein levels were analysed by qRT‐PCR and Western blot. Related mechanisms were confirmed using appropriate inhibitors or shRNA. In vitro results were further confirmed by a tumour xenograft study. Results: CHEPS inhibited the proliferation of NSCLC cells by inducing S‐ and G2/M‐phase arrest and autophagic cell death, but not apoptosis. CHEPS was less toxic to normal human embryonic lung fibroblasts. CHEPS activated the MAPK pathway in NSCLC cells, and p38 and ERK promoted CHEPS‐induced cell death. Further studies showed that p38 and ERK promoted CHEPS‐induced NSCLC cell autophagy and ERK promoted CHEPS‐induced S‐ and G2/M‐phase arrest. ROS were induced by CHEPS. A ROS scavenger attenuated CHEPS‐induced p38 and ERK activation, autophagy and cell death. Finally, CHEPS reduced orthotopic lung tumour growth without organ‐related toxicity. CHEPS also induced ROS, activated p38 and ERK, and triggered autophagy in vivo. Conclusions: CHEPS induces autophagic cell death and S‐ and G2/M‐phase arrest in NSCLC cells via ROS/p38 and ROS/ERK signalling. [ABSTRACT FROM AUTHOR]

Proranolol has long been recommended to prevent variceal bleeding in patients with cirrhosis. However, the mechanisms of propranolol in liver fibrosis have not yet been thoroughly elucidated. Autophagic cell death (ACD) of activated hepatic stellate cells (HSCs) is important in the alleviation of liver fibrosis. Our study aims to assess the mechanisms of propranolol regulating HSC ACD and liver fibrosis. ACD of HSCs was investigated using lentivirus transfection. The molecular mechanism was determined using a PCR profiler array. The role of autophagy-related protein 9b (ATG9b) in HSC ACD was detected using co-immunoprecipitation and co-localization of immunofluorescence. Changes in the signalling pathway were detected by the Phospho Explorer antibody microarray. Propranolol induces ACD and apoptosis in HSCs. ATG9b upregulation was detected in propranolol-treated HSCs. ATG9b upregulation promoted ACD of HSCs and alleviated liver fibrosis in vivo. ATG9b enhanced the P62 recruitment to ATG5-ATG12-LC3 compartments and increased the co-localization of P62 with ubiquitinated proteins. The PI3K/AKT/mTOR pathway is responsible for ATG9b-induced ACD in activated HSCs, whereas the p38/JNK pathway is involved in apoptosis. This study provides evidence for ATG9b as a new target gene and propranolol as an agent to alleviate liver fibrosis by regulating ACD of activated HSCs., (© 2023 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Seeking for effective drugs which are beneficial to facilitating axonal regrowth and elongation after peripheral nerve injury (PNI) has gained extensive attention. Fibroblast growth factor 21 (FGF21) is a metabolic factor that regulates blood glucose and lipid homeostasis. However, there is little concern for the potential protective effect of FGF21 on nerve regeneration after PNI and revealing related molecular mechanisms. Here, we firstly found that exogenous FGF21 administration remarkably promoted functional and morphologic recovery in a rat model of sciatic crush injury, manifesting as persistently improved motor and sensory function, enhanced axonal remyelination and regrowth and accelerated Schwann cells (SCs) proliferation. Furthermore, local FGF21 application attenuated the excessive activation of oxidative stress, which was accompanied with the activation of nuclear factor erythroid‐2‐related factor 2 (Nrf‐2) transcription and extracellular regulated protein kinases (ERK) phosphorylation. We detected FGF21 also suppressed autophagic cell death in SCs. Additionally, treatment with the ERK inhibitor U0126 or autophagy inhibitor 3‐MA partially abolishes anti‐oxidant effect and reduces SCs death. Taken together, these results indicated that the role of FGF21 in remyelination and nerve regeneration after PNI was probably related to inhibit the excessive activation of ERK/Nrf‐2 signalling‐regulated oxidative stress and autophagy‐induced cell death. Overall, our work suggests that FGF21 administration may provide a new therapy for PNI. [ABSTRACT FROM AUTHOR]

Abstract: Excessive iodide could induce intellectual damage in children, which has attracted broad attention. To investigate the neurotoxic effect of iodide and its mechanism, a human dopaminergic neuroblastoma cell line (SH‐SY5Y) was treated with different concentrations of potassium iodide (KI). The results showed that excessive iodide could decrease cell viability, reduce glutathione (GSH) and superoxide dismutase (SOD), and increase the degree of autophagy (by changing the cellular ultrastructure and raising the autophagy‐related mRNA and protein expression of LC3, Beclin1, and p62), which were correlated with the immunofluorescence labeling. Furthermore, treatment with the autophagy inhibitor 3‐methyladenine (3MA), antioxidant N‐acetylcysteine (NAC) and 30 mM KI for 24 h was conducted in the following research. 3MA significantly decreased autophagy‐related mRNA and protein expression and improved cell viability, indicating that excess iodide induced autophagic cell death. In addition, oxidative stress regulated autophagy, reflected by the results that NAC decreased the mRNA and protein expression of LC3, Beclin1, and p62. In summary, autophagic cell death mediated by oxidative stress may participate in excessive iodide‐induced SH‐SY5Y cell death. [ABSTRACT FROM AUTHOR]

It is well known that the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/TNFSF10) is specifically expressed in various tumor cells, but less or no expression in most normal tissues and cells. While TRAIL engages with its native death receptors, TRAIL receptor 1 (TRAIL-R1) or 2 (TRAIL-R2), usually elicits the tumor cell death by apoptosis. In this study, we report that a novel humanized monoclonal antibody against TRAIL-R2 (named as zaptuzumab) well remain the biological activity of the parental mouse antibody AD5-10 inducing cell death in various cancer cells, but little effect on normal cells. Zaptuzumab also markedly inhibited the tumor growth in the mouse xenograft of NCI-H460 without toxicity to the liver and kidney, and the efficacy of tumor suppression was increased significantly while it combined with cis-dichlorodiamineplatinum. Especially, 131I-labeled zaptuzumab injected into mouse tail vein specifically targeted to the xenograft of the lung cancer cells. Confocal analysis showed that zaptuzumab bound with TRAIL-R2 on cell surface could be quickly internalized and transferred into the lysosome. Furthermore, zaptuzumab possessed a high level of antibody-dependent cytotoxicity as well as complement-dependent cytotoxicity. Study on the mechanisms of cell death induced by zaptuzumab showed that it efficiently induced both caspase-dependent apoptosis and autophagic cell death. These data suggest that the humanized anti-TRAIL-R2 monoclonal antibody or the second generation of the antibody may have an important clinical usage for cancer immunotherapy. © 2017 IUBMB Life, 69(9):735-744, 2017 [ABSTRACT FROM AUTHOR]

Evasion of cell death is one of the hallmarks of cancer cells, beginning with long-established apoptosis and extending to other new forms of cell death. An elaboration of cell death pathways thus will contribute to a better understanding of cancer pathogenesis and therapeutics. With the recent substantial biochemical and genetic explorations of cell death subroutines, their classification has switched from primarily morphological to more molecular definitions. According to their measurable biochemical features and intricate mechanisms, cell death subroutines can be divided into apoptosis, autophagic cell death, mitotic catastrophe, necroptosis, parthanatos, ferroptosis, pyroptosis, pyronecrosis, anoikis, cornification, entosis, and NETosis. Supportive evidence has gradually revealed the prime molecular mechanisms of each subroutine and thus providing series of possible targets in cancer therapy, while the intricate relationships between different cell death subroutines still remain to be clarified. Over the past decades, cancer drug discovery has significantly benefited from the use of small-molecule compounds to target classical modalities of cell death such as apoptosis, while newly identified cell death subroutines has also emerging their potential for cancer drug discovery in recent years. In this review, we comprehensively focus on summarizing 12 cell death subroutines and discussing their corresponding small-molecule compounds in potential cancer therapy. Together, these inspiring findings may provide more evidence to fill in the gaps between cell death subroutines and small-molecule compounds to better develop novel cancer therapeutic strategies. [ABSTRACT FROM AUTHOR]

Airborne nanoparticles PM0.1 (<100 nm in diameter) were collected and their chemical composition was determined. Al was by far the most abundant metal in the PM0.1 followed by Zn, Cr, Mn, Cu, Pb and Ni. Exposure to PM0.1 resulted in a cell viability decrease in human neuronal cells SH-SY5Y in a concentration-dependent manner. Upon treatment with N-acetylcysteine, however, cell viability was significantly recovered, suggesting the involvement of reactive oxygen species (ROS). Cellular DNA damage by PM0.1 was also detected by the Comet assay. PM0.1-induced autophagic cell death was explained by an increase in the expression of microtubule-associated protein light chain 3A-ІІ (LC3A-ІІ) and autophagy-related protein Atg 3 and Atg 7. Analysis of 2-DE gels revealed that six proteins were upregulated, whereas eight proteins were downregulated by PM0.1 exposure. Neuroinflammation-related lithostathine and cyclophilin A complexed with dipeptide Gly-Pro, autophagy-related heat shock protein gp96 and neurodegeneration-related triosephosphate isomerase were significantly changed upon exposure to PM0.1. These results, taken together, suggest that PM0.1-induced oxidative stress via ROS generation plays a key role in autophagic cell death and differential protein expressions in SH-SY5Y cells. This might provide a plausible explanation for the underlying mechanisms of PM0.1 toxicity in neuronal cells and even the pathogenesis of diseases associated with its exposure. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Larotrectinib (Lar) is a highly selective and potent small-molecule inhibitor used in patients with tropomyosin receptor kinase (TRK) fusion-positive cancers, including colon cancer. However, the underlying molecular mechanisms specifically in patients with colon cancer have not yet been explored. Our data showed that Lar significantly suppressed proliferation and migration of colon cancer cells. In addition, Lar suppressed the epithelial-mesenchymal transition (EMT) process, as evidenced by elevation in E-cadherin (E-cad), and downregulation of vimentin and matrix metalloproteinase (MMP) 2/9 expression. Furthermore, Lar was found to activate autophagic flux, in which Lar increased the ratio between LC3II/LC3I and decreased the expression of p62 in colon cancer cells. More importantly, Lar also increased AMPK phosphorylation and suppressed mTOR phosphorylation in colon cancer cells. However, when we silenced AMPK in colon cancer cells, Lar-induced accumulation of autolysomes as well as Lar-induced suppression of the EMT process were significantly diminished. An in vivo assay also confirmed that tumour volume and weight decreased in Lar-treated mice than in control mice. Taken together, this study suggests that Lar significantly suppresses colon cancer proliferation and migration by activating AMPK/mTOR-mediated autophagic cell death., (© 2022 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Previous studies have shown that Pseudolaric acid B (PAB), a medicinal plant-derived terpenoid, is a promising chemopreventive or therapeutic agent against various types of cancer. However, less is known regarding its activity against prostate cancer. The objective of the current study is designed to determine the anti-prostate cancer effects of PAB. We demonstrated here that PAB was highly effective against both androgen-dependent (LNCaP) and androgen-independent prostate cancer cells (PC-3 and DU145) through the mechanisms involved in induction of G2/M cell cycle arrest, caspase-dependent apoptosis and autophagic cell death. Furthermore, PAB can greatly sensitize these two aggressive androgen-independent prostate cancer cells to ABT-737-induced cytotoxicity. Our findings suggest that PAB holds excellent potential as either novel chemopreventive agent or enhancer of therapeutic drug against prostate cancer. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Neuroendocrine chromaffin cells exist in both intra- and extra-adrenal locations; the organ of Zuckerkandl ( OZ) constitutes the largest accumulation of extra-adrenal chromaffin tissue in mammals. The OZ disappears postnatally by modes that are still enigmatic but can be maintained by treatment with glucocorticoids ( GC). Whether the response to GC reflects a pharmacological or a physiological role of GC has not been clarified. Using mice with a conditional deletion of the GC-receptor ( GR) gene restricted to cells expressing the dopamine β-hydroxylase ( DBH) gene [ GRfl/fl; DBHCre abbreviated ( GRDBHCre)], we now present the first evidence for a physiological role of GC signalling in the postnatal maintenance of the OZ: postnatal losses of OZ chromaffin cells in GRDBHCre mice are doubled compared to wild-type littermates. We find that postnatal cell loss in the OZ starts at birth and is accompanied by autophagy. Electron microscopy reveals autophagic vacuoles and autophagolysosomes in chromaffin cells. Autophagy in OZ extra-adrenal chromaffin cells is confirmed by showing accumulation of p62 protein, which occurs, when autophagy is blocked by deleting the Atg5 gene ( Atg5 DBHCre mice). Cathepsin- D, a lysosomal marker, is expressed in cells that surround chromaffin cells and are positive for the macrophage marker BM8. Macrophages are relatively more abundant in mice lacking the GR, indicating more robust elimination of degenerating chromaffin cells in GRDBHCre mice than in wild-type littermates. In summary, our results indicate that extra-adrenal chromaffin cells in the OZ show signs of autophagy, which accompany their postnatal numerical decline, a process that is controlled by GR signalling. [ABSTRACT FROM AUTHOR]

BACKGROUND AND PURPOSE Autophagic cell death is considered a self-destructive process that results from large amounts of autophagic flux. In our previous study, GMI, a recombinant fungal immunomodulatory protein cloned from Ganoderma microsporum, induced autophagic cell death in lung cancer cells. The aim of this study was to examine the role of autophagosome accumulation in GMI-mediated cell death. EXPERIMENTAL APPROACH Western blot analysis, flow cytometry and confocal microscopy were used to evaluate the effects of different treatments, including silencing of ATP6V0A1 by use of short hairpin RNAi, on GMI-mediated cell death, lung cancer cell viability and autophagosome accumulation in vitro. KEY RESULTS Lysosome inhibitors bafilomycin-A1 and chloroquine increased GMI-mediated autophagic cell death. GMI and bafilomycin-A1 co-treatment induced the accumulation of large amounts of autophagosomes, but did not significantly induce apoptosis. GMI elicited autophagy through the PKB (Akt)/mammalian target of rapamycin signalling pathway. Silencing of ATP6V0A1, one subunit of vesicular H+-ATPases (V-ATPases) that mediates lysosome acidification, spontaneously induced autophagosome accumulation, but did not affect lysosome acidity. GMI-mediated autophagosome accumulation and cytotoxicity was increased in shATP6V0A1 lung cancer cells. Furthermore, ATP6V0A1 silencing decreased autophagosome and lysosome fusion in GMI-treated CaLu-1/GFP-LC3 lung cancer cells. CONCLUSION AND IMPLICATIONS We demonstrated that autophagosome accumulation induces autophagic cell death in a GMI treatment model, and ATP6V0A1 plays an important role in mediating autophagosome-lysosome fusion. Our findings provide new insights into the mechanisms involved in the induction of autophagic cell death. [ABSTRACT FROM AUTHOR]

The article reports on a study showing that the antidepressants maprotiline and fluoxetine induce autophagic programed cell death (PCD) in the chemoresistant Burkitt's lymphoma (BL) cell line DG-75, and is associated with the development of cytoplasmic vacuoles. The study further shows that the proapoptotic Bcl-2 proteins Bax and Bak, are not expressed by the chemoresistant DG-75 cells.

Tsuda H, Ochiai K, Suzuki N, Otsuka K. Butyrate, a bacterial metabolite, induces apoptosis and autophagic cell death in gingival epithelial cells. J Periodont Res 2010; 45: 626–634.© 2010 John Wiley & Sons A/S Background and Objective: Butyrate is produced by some types of anaerobic periodontal bacteria. Millimolar concentrations of butyrate are found in mature dental plaque from periodontitis patients. Although butyrate reportedly has a variety of effects in many mammalian cells, its effect on gingival epithelial cells is not well known. In this study, we investigated the effect of butyrate on gingival epithelial Ca9-22 cell death. Material and Methods: Death of Ca9-22 cells was assessed after treating the cells with or without butyrate. A SYTOX Green dye, which exhibits strong green fluorescence once it enters dead cells through ruptured cell membranes, was used for cell death detection. Phosphatidylserine redistribution was measured using fluorescein isothiocyanate-labeled annexin V. The activity of caspase-3 was measured as the amount of cleaved substrate peptide. Anti-apoptotic bcl-2 mRNA expression was measured using real-time RT-PCR. Western blotting and fluoromicroscopic analysis with anti-microtubule-associated protein 1 light chain 3 (LC3) antibodies were performed for detection of autophagy. Results: Stimulation with millimolar concentrations of butyrate for 48 h induced Ca9-22 cell death. The stimulation also caused increased caspase-3 activity, phosphatidylserine redistribution and bcl-2 down-regulation, suggesting butyrate-induced apoptosis. However, the pan-caspase inhibitor, Z-VAD-FMK, did not inhibit cell death completely. This implies the existence of other types of cell death. In addition, markers of autophagy, namely, the conversion of LC3-I to LC3-II and increased LC3 accumulation, were observed. Moreover, inhibition of autophagy by 3-methyladenine suppressed the butyrate-induced cell death, suggesting that butyrate could induce cell death through autophagy. Conclusion: These data suggest that butyrate induces apoptosis and autophagic cell death. [ABSTRACT FROM AUTHOR]

Cell death is clearly an important factor in development, homeostasis, pathology and in aging, but medical efforts based on controlling cell death have not become major aspects of medicine. There are several reasons why hopes have been slow to be fulfilled, and they present indications for new directions in research. Most effort has focused on the machinery of cell death, or the proximate effectors of apoptosis and their closely associated and interacting proteins. But cells have many options other than apoptosis. These include autophagy, necrosis, atrophy and stepwise or other alternate means of self-disassembly. The response of a cell to a noxious or otherwise intimidating signal will depend heavily on the history, lineage and current status of the cell. Many metabolic and other processes adjust the sensitivity of cells to signals, and viruses aggressively attempt to regulate the death of their host cells. Another complicating factor is that many deathassociated proteins may have functions totally unrelated to their role in cell death, generating the possibility of undesirable side effects if one interferes with them. In the future, the challenge will be more to understand the challenge to the cell from a more global standpoint, including many more aspects of metabolism, and work toward alleviating or provoking the challenge in a targeted fashion. [ABSTRACT FROM AUTHOR]

We have previously identified Scrg1, a gene with increased cerebral mRNA levels in transmissible spongiform encephalopathies (TSE) such as scrapie, bovine spongiform encephalopathy and Creutzfeldt–Jakob disease. In this study, Scrg1-immunoreactive cells, essentially neurons, were shown to be widely distributed throughout the brain of scrapie-infected mice, while only rare and weakly immunoreactive cells could be detected in the brain of non-infected normal mice. Induction of the protein was confirmed by Western blot analysis. At the ultrastructural level, Scrg1 protein was associated with dictyosomes of the Golgi apparatus and autophagic vacuoles in the central neurons of the scrapie-infected mice. These results suggested a role for Scrg1 in the pathological changes observed in TSE. We have generated transgenic mice specifically expressing Scrg1 in neurons. No significant differences in the time course of the disease were detected between transgenic and non-transgenic mice infected with scrapie prions. However, tight association of Scrg1 with autophagic vacuoles was again observed in brain neurons of infected transgenic mice. High levels of the protein were also detected in degenerating Purkinje cells of Ngsk Prnp0/0 mice overexpressing the Prnd gene coding for doppel, a neurotoxic paralogue of the prion protein. Furthermore, induction of Scrg1 protein was observed in the brain of mice injured by canine distemper virus or gold thioglucose treatment. Taken together, our results indicate that Scrg1 is associated with neurodegenerative processes in TSE, but is not directly linked to dysregulation of prion protein. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is the most common primary malignant bone tumour in adolescence. Lately, light-emitting diodes (LED)-based therapy has emerged as a new promising approach for several diseases. However, it remains unknown in human OS. Here, we found that the blue LED irradiation significantly suppressed the proliferation, migration and invasion of human OS cells, while we observed blue LED irradiation increased ROS production through increased NADPH oxidase enzymes NOX2 and NOX4, as well as decreased Catalase (CAT) expression levels. Furthermore, we revealed blue LED irradiation-induced autophagy characterized by alterations in autophagy protein markers including Beclin-1, LC3-II/LC3-I and P62. Moreover, we demonstrated an enhanced autophagic flux. The blockage of autophagy displayed a remarkable attenuation of anti-tumour activities of blue LED irradiation. Next, ROS scavenger N-acetyl-L-cysteine (NAC) and NOX inhibitor diphenyleneiodonium (DPI) blocked suppression of OS cell growth, indicating that ROS accumulation might play an essential role in blue LED-induced autophagic OS cell death. Additionally, we observed blue LED irradiation decreased EGFR activation (phosphorylation), which in turn led to Beclin-1 release and subsequent autophagy activation in OS cells. Analysis of EGFR colocalization with Beclin-1 and EGFR-immunoprecipitation (IP) assay further revealed the decreased interaction of EGFR and Beclin-1 upon blue LED irradiation in OS cells. In addition, Beclin-1 down-regulation abolished the effects of blue LED irradiation on OS cells. Collectively, we concluded that blue LED irradiation exhibited anti-tumour effects on OS by triggering ROS and EGFR/Beclin-1-mediated autophagy signalling pathway, representing a potential approach for human OS treatment., (© 2021 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Abstract Acute excitotoxic neuronal death was studied in rat organotypic hippocampal slices exposed to 100 µmN -methyl-d-aspartate. Fulgurant death of pyramidal neurons occurred in the CA1 and CA3 regions and was already detectable within 2 h of the N-methyl-d-aspartate administration. Morphologically, the neuronal death was neither apoptotic nor necrotic but had the hallmarks of autophagic neuronal death, as shown by acid phosphatase histochemistry in both CA1 and CA3 and by electron microscopy in CA1. The dying neurons also manifested strong endocytosis of horseradish peroxidase or microperoxidase, occurring probably by a fluid phase mechanism, and followed, surprisingly, by nuclear entry. In addition to these autophagic and endocytic characteristics, there were indications that the c-Jun N-terminal kinase pathway was activated. Its target c-Jun was selectively phosphorylated in CA1, CA3 and the dentate gyrus and c-Fos, the transcription of which is under the positive control of c-Jun N-terminal kinase target Elk1, was selectively up-regulated in CA1 and CA3. All these effects, the neuronal death itself and the associated autophagy and endocytosis, were totally prevented by a cell-permeable inhibitor of the interaction between c-Jun N-terminal kinase and certain of its targets. These results show that pyramidal neurons undergoing excitotoxic death in this situation are autophagic and endocytic and that both the cell death and the associated autophagy and endocytosis are under the control of the c-Jun N-terminal kinase pathway. [ABSTRACT FROM AUTHOR]