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Purpose: To investigate the effect of reducing Lysyl oxidase (LOX) overexpression on retinal ganglion cells (RGCs) apoptosis in an acute ocular hypertension (AOH) rat model. Methods: AOH rat model was performed by anterior chamber perfusion and either received an intravitreal injection with β-aminopropionitrile (BAPN) or normal saline. After 2wk, Quantification of survival RGCs in the retina was performed using Retrograde FluoroGold labeling. The mRNA expression levels of LOX, LOXL1-4, collagen 1a1 (Col1a1), collagen 3a1 (Col3a1), collagen4a1 (Col4a1), elastin (Eln), fibronectin1 (Fbn1), fibronectin4 (Fbn4) were determined by RT-qPCR. LOX expression was determined by Western blot (WB) analysis and immunohistochemistry. The RNA expression of LOX, Eln and Col1a1 in RGCs retrograde-labeled with 1,1'-dioctadecyl-3,3,3',3' tetra-methylindocarbocyanine perchlorate(DiI)that selected through FACS sorting were determined by RT-qPCR analysis. Changes of the retinal function were detected by Electroretinogram (ERG) analysis. Results: Results showed that significant LOX overexpression and loss of RGCs related to IOP exposure in AOH retinas. PCR analysis indicated significant increased mRNA level of Col1a1, Col3al and Eln in AOH retinas. Significant increase mRNA expression of LOX, Col1a1 and Eln in the RGCs were observed in AOH group compared with CON group. AOH rats injected with BAPN showed a significant decrease in LOX expression, reduced the loss of RGCs and retinal function damage. Conclusions: The results demonstrated that changes of LOX and specific ECM components in retina were correlated with AOH. Findings from this study indicated that preventing LOX over-expression may be protective against RGCs loss and retinal function damage in AOH animal model. [ABSTRACT FROM AUTHOR]

9-Carbon aldehydes such as (2E)-nonenal, (3Z)-nonenal, and (2E,6Z)-nonadienal are important melon and cucumber fragrance compounds. Currently, these molecules are produced either synthetically, which faces consumer aversion, or through biotransformation using plant-extracted enzymes, which is costly and inefficient. In this study, we constructed a Saccharomyces cerevisiae platform for the whole cell biotransformation of polyunsaturated fatty acids (PUFAs) to 9-carbon aldehydes. Heterologous expression of lipoxygenase (LOX) from Nicotiana benthamiana and hydroperoxide lyase (HPL) from Cucumis melo (melon) in S. cerevisiae enabled the production of (2E)-nonenal from readily available polyunsaturated fatty acid substrates. A 5.5-fold increase in (2E)-nonenal titer was then achieved utilizing genetic and reaction condition enhancement strategies. The highest titer of (2E)-nonenal was more than 0.11 mM, with about 9% yield. This platform can potentially be used to produce a variety of other aldehyde products by customizing with LOX and HPL enzymes of different regio-selectivities. Key points: • Establishment of a S. cerevisiae whole-cell biotransformation platform for cost-efficient, high-yield conversion of PUFAs into high value 9-carbon aldehyde compounds • 5.5-Fold improvement of (2E)-nonenal titer to > 0.11 mM achieved by enhancing reaction conditions and gene expression levels of LOX and HPL [ABSTRACT FROM AUTHOR]

Introduction: Current treatments for bacterial keratitis fail to address the sightthreatening inflammatory host response. Our recent work elucidating the therapeutic mechanisms of adjunctive thymosin beta-4 (Tb4) in resolving inflammation and infection in bacterial keratitis revealed modulation of effector cell function and enhanced bacterial killing. The current study builds upon the observed effects on effector cell function by investigating the impact of Tb4 on specialized pro-resolving lipid mediator (SPM) pathways as they play a significant role in inflammation resolution. Methods: Using a well-established in vivo model of Pseudomonas aeruginosainduced bacterial keratitis, we assessed key enzymes (5-LOX and 12/15-LOX) involved in SPM pathway activation, SPM end products (lipoxins, resolvins), and receptor levels for these mediators. In vitro validation using LPS-stimulated murine monocyte/MF-like RAW 264.7 cells and siRNA to inhibit Tb4 and LOX enzymes was carried out to complement our in vivo findings. Results: Findings from our in vivo and in vitro investigations demonstrated that adjunctive Tb4 treatment significantly influences enzymes and receptors involved in SPM pathways. Further, Tb4 alone enhances the generation of SPM end products in the cornea. Our in vitro assessments confirmed that Tb4-enhanced phagocytosis is directly mediated by SPM pathway activation. Whereas Tb4-enhanced efferocytosis appeared to be indirect. Conclusion: Collectively, these findings suggest that the therapeutic effect of Tb4 resolves inflammation through the activation of SPM pathways, thereby enhancing host defense and tissue repair. Our research contributes to understanding the potential mechanisms behind Tb4 immunoregulatory function, pointing to its promising ability as a comprehensive adjunctive treatment for bacterial keratitis. [ABSTRACT FROM AUTHOR]

Introduction: Current treatments for bacterial keratitis fail to address the sight-threatening inflammatory host response. Our recent work elucidating the therapeutic mechanisms of adjunctive thymosin beta-4 (Tβ4) in resolving inflammation and infection in bacterial keratitis revealed modulation of effector cell function and enhanced bacterial killing. The current study builds upon the observed effects on effector cell function by investigating the impact of Tβ4 on specialized pro-resolving lipid mediator (SPM) pathways as they play a significant role in inflammation resolution. Methods: Using a well-established in vivo model of Pseudomonas aeruginosa-induced bacterial keratitis, we assessed key enzymes (5-LOX and 12/15-LOX) involved in SPM pathway activation, SPM end products (lipoxins, resolvins), and receptor levels for these mediators. In vitro validation using LPS-stimulated murine monocyte/MΦ-like RAW 264.7 cells and siRNA to inhibit Tβ4 and LOX enzymes was carried out to complement our in vivo findings. Results: Findings from our in vivo and in vitro investigations demonstrated that adjunctive Tβ4 treatment significantly influences enzymes and receptors involved in SPM pathways. Further, Tβ4 alone enhances the generation of SPM end products in the cornea. Our in vitro assessments confirmed that Tβ4-enhanced phagocytosis is directly mediated by SPM pathway activation. Whereas Tβ4-enhanced efferocytosis appeared to be indirect. Conclusion: Collectively, these findings suggest that the therapeutic effect of Tβ4 resolves inflammation through the activation of SPM pathways, thereby enhancing host defense and tissue repair. Our research contributes to understanding the potential mechanisms behind Tβ4 immunoregulatory function, pointing to its promising ability as a comprehensive adjunctive treatment for bacterial keratitis. [ABSTRACT FROM AUTHOR]

Background: Severe acute respiratory syndrome (SARS) and acute respiratory distress syndrome (ARDS) are often considered separate clinico-radiological entities. Whether these conditions also present a single process-specific systemic biomolecular phenotype and how this relates to patient outcomes remains unknown. A prospective cohort study was conducted, including adult patients admitted to the ICU and general floors for COVID-19-related (COVID+) or non-COVID-19-related (COVID−) acute respiratory failure during the main phase of the pandemic. The primary objective was to study blood biomarkers and outcomes among different groups and severity subsets. Results: A total of 132 patients were included, as follows: 67 COVID+, 54 COVID− (with 11 matched control subjects for biomarker reference), and 58 of these patients allowed for further pre- and post-analysis. The baseline apelin (APL) levels were higher in COVID+ patients (p < 0.0001 vs. COVID− patients) and in SARS COVID+ patients (p ≤ 0.02 vs. ARDS), while the IL-6 levels were higher in ARDS COVID− patients (p ≤ 0.0001 vs. SARS). Multivariable logistic regression analyses with cohort biomarkers and outcome parameters revealed the following: (i) log-transformed neprilysin (NEP) activity was significantly higher in COVID+ patients (1.11 [95% CI: 0.4–1.9] vs. 0.37 [95% CI: 0.1–0.8], fold change (FC): 1.43 [95% CI: 1.04–1.97], p = 0.029) and in SARS patients (FC: 1.65 [95% CI: 1.05–2.6], p = 0.032 vs. non-SARS COVID+ patients, and 1.73 [95% CI: 1.19–2.5], p = 0.005 vs. ARDS COVID− patients) and (ii) higher lysyl oxidase (LOX) activity and APL levels were respectively associated with death and a shorter length of hospital stay in SARS COVID+ patients (Odds Ratios (OR): 1.01 [1.00–1.02], p = 0.05, and OR: −0.007 [−0.013–0.0001], p = 0.048). Conclusion: Process-specific blood biomarkers exhibited distinct profiles between COVID+ and COVID− patients, and across stages of severity. NEP and LOX activities, as well as APL levels, are particularly linked to COVID+ patients and their outcomes (ClinicalTrials.gov Identifier: NCT04632732). [ABSTRACT FROM AUTHOR]

Background: Atrial fibrosis is one of the main causes of the onset and recurrence of atrial fibrillation (AF), for which there is no effective treatment. The aim of this study was to investigate the effect and mechanism of epigallocatechin-3-gallate (EGCG) on AF in rats. Methods: The rat model of AF was established by rapid pacing induction after angiotensin-II (Ang-II) induced atrial fibrosis to verify the relationship between atrial fibrosis and the AF. The expression levels of TGF-β/Smad3 pathway molecules and lysyl oxidase (LOX) in AF were detected. Subsequently, EGCG was used to intervene Ang-II-induced atrial fibrosis to explore the role of EGCG in the treatment of AF and its inhibitory mechanism on fibrosis. It was further verified that EGCG inhibited the production of collagen and the expression of LOX through the TGF-β/Smad3 pathway at the cellular level. Results: The results showed that the induction rate and maintenance time of AF in rats increased with the increase of the degree of atrial fibrosis. Meanwhile, the expressions of Col I, Col III, molecules related to TGF-β/Smad3 pathway, and LOX increased significantly in the atrial tissues of rats in the Ang-II induced group. EGCG could reduce the occurrence and maintenance time of AF by inhibiting the degree of Ang-induced rat atrial fibrosis. Cell experiments confirmed that EGCG could reduce the synthesis of collagen and the expression of LOX in cardiac fibroblast induced by Ang-II. The possible mechanism is to down-regulate the expression of genes and proteins related to the TGF-β/Smad3 pathway. Conclusion: EGCG could downregulate the expression levels of collagen and LOX by inhibiting the TGF-β/Smad3 signaling pathway, alleviating Ang-II-induced atrial fibrosis, which in turn inhibited the occurrence and curtailed the duration of AF. [ABSTRACT FROM AUTHOR]

Conduit pulmonary arterial stiffening and the resultant increase in pulmonary vascular impedance have emerged as an important underlying driver of pulmonary arterial hypertension (PAH). Given that matrix deposition is central to vascular remodeling, we evaluated the role of the collagen cross-linking enzyme lysyl oxidase like 2 (LOXL2) in this study. Human pulmonary artery smooth muscle cells (PASMCs) subjected to hypoxia showed increased LOXL2 secretion. LOXL2 activity and expression were markedly higher in primary PASMCs isolated from the pulmonary arteries of the rat Sugen 5416 + hypoxia (SuHx) model of severe pulmonary hypertension (PH). Similarly, LOXL2 protein and mRNA levels were increased in the pulmonary arteries (PA) and lungs of rats with PH (SuHx and monocrotaline (MCT) models). Pulmonary arteries (PAs) isolated from the rats with PH exhibited hypercontractility to phenylephrine and attenuated vasorelaxation elicited by acetylcholine, indicating severe endothelial dysfunction. Tensile testing revealed a significant increase in PA stiffness in PH. Treatment with PAT-1251, a novel small-molecule LOXL2 inhibitor, improved active and passive properties of the PA ex vivo. There was an improvement in right heart function as measured by right ventricular pressure volume loops in vivo with PAT-1251. Importantly, PAT-1251 treatment ameliorated PH, resulting in improved pulmonary artery pressures, right ventricular remodeling, and survival. Hypoxia-induced LOXL2 activation is a causal mechanism in pulmonary artery stiffening in PH and pulmonary artery mechanical and functional decline. LOXL2 inhibition with PAT-1251 could be a promising approach to improve pulmonary artery pressures, right ventricular elastance, cardiac relaxation, and survival in PAH. NEW & NOTEWORTHY: Pulmonary arterial stiffening contributes to the progression of PAH and the deterioration of right heart function. This study shows that LOXL2 is upregulated in rat models of PH. LOXL2 inhibition halts pulmonary vascular remodeling and improves PA contractility, endothelial function, and PA pressure, resulting in prolonged survival. Thus, LOXL2 is an important mediator of PA remodeling and stiffening in PH and a promising target to improve PA pressures and survival in PH. [ABSTRACT FROM AUTHOR]

Background: The stiffness of the tumor microenvironment (TME) directly influences cellular behaviors. Radiotherapy (RT) is a common treatment for solid tumors, but the TME can impact its efficacy. In the case of liver cancer, clinical observations have shown that tumors within a cirrhotic, stiffer background respond less to RT, suggesting that the extracellular matrix (ECM) stiffness plays a critical role in the development of radioresistance. Methods: This study explored the effects of ECM stiffness and the inhibition of lysyl oxidase (LOX) isoenzymes on the radiation response of liver cancer in a millimeter-sized three-dimensional (3D) culture. We constructed a cube-shaped ECM-based millimeter-sized hydrogel containing Huh7 human liver cancer cells. By modulating the collagen concentration, we produced two groups of samples with different ECM stiffnesses to mimic the clinical scenarios of normal and cirrhotic livers. We used a single-transducer system for shear-wave-based elasticity measurement, to derive Young's modulus of the 3D cell culture to investigate how the ECM stiffness affects radiosensitivity. This is the first demonstration of a workflow for assessing radiation-induced response in a millimeter-sized 3D culture. Results: Increased ECM stiffness was associated with a decreased radiation response. Moreover, sonoporation-assisted LOX inhibition with BAPN (β-aminopropionitrile monofumarate) significantly decreased the initial ECM stiffness and increased RT-induced cell death. Inhibition of LOX was particularly effective in reducing ECM stiffness in stiffer matrices. Combining LOX inhibition with RT markedly increased radiation-induced DNA damage in cirrhotic liver cancer cells, enhancing their response to radiation. Furthermore, LOX inhibition can be combined with sonoporation to overcome stiffness-related radioresistance, potentially leading to better treatment outcomes for patients with liver cancer. Conclusions: The findings underscore the significant influence of ECM stiffness on liver cancer's response to radiation. Sonoporation-aided LOX inhibition emerges as a promising strategy to mitigate stiffness-related resistance, offering potential improvements in liver cancer treatment outcomes. [ABSTRACT FROM AUTHOR]

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Objective: This study aimed to investigate the effect of plasma‐activated Ringer's lactate solution (PAL) on oral squamous cell carcinoma (OSCC) cells and carcinogenic processes with a particular focus on iron and collagenous matrix formation. Materials and Methods: We used three OSCC cell lines, one keratinocyte cell line, and two fibroblast lines, and cell viability assays, immunoblotting, flow cytometry, and transmission electron microscopy were performed to evaluate the effect and type of cell death. The effect of PAL treatment on lysyl oxidase (LOX) expression was investigated in vitro and in vivo. Tamoxifen‐inducible Mob1a/b double‐knockout mice were used for the in vivo experiment. Results: PAL killed OSCC cells more effectively than the control nontumorous cells and suppressed cell migration and invasion. Ferroptosis occurred and the protein level of LOX was downregulated in cancer cells in vitro and in vivo. Additionally, PAL improved the survival rate of mice and suppressed collagenous matrix formation. Conclusions: We demonstrated that PAL specifically kills OSCC cells and that ferroptosis occurs in vitro and in vivo. Furthermore, PAL can prevent carcinogenesis and improve the survival rate of oral cancer, especially tongue cancer, by changing collagenous matrix formation via LOX suppression. [ABSTRACT FROM AUTHOR]

Background: Regular physical exercise is an essential part of a healthy lifestyle, maintaining and strengthening public health. Recently, a steady increase in the number of recurrent musculoskeletal injuries occurring during physical exercise is being diagnosed. A serious risk factor for such damage is initial connective tissue pathology. Pathognomonic dysplastic phenotypes, indicating a particular susceptibility to injuries, were established. The decisive role in increasing connective tissue disorders severity is attributed in part to magnesium deficiency that is one of the most common deficient human conditions. Objective: To present the magnesium role in connective tissue homeostasis for pathogenetic substantiation of magnesium correction in persons with predisposition to musculoskeletal injuries. Methods: An analytical review of recent data published between January 2004 and December 2023 in the electronic resources such as Global Health, ScienceDirect, Elsevier, Medline, Embase, PubMed-NCBI, RSCI Scopus, Cochrane Library, e-Library, Google Academy, and CyberLeninka was conducted. Data analysis was performed from January 2023 to December 2023. Results: The analysis of the obtained data allowed to identify the main pathogenetic mechanisms of magnesium deficiency effect on connective tissues, including RNA cell destabilization, inactivation of hyaluronan synthetases, modulation of hyaluronidase activity, stimulation of matrix metalloproteinases, deactivation of elastase, realization of autoimmune reaction, lysyl oxidase, and transglutaminase activation. These processes result in increased degradation of collagen, elastin, and hyaluronan polysaccharide chains; reduction of cross-linking of fibrous structure; and intensification of inflammatory processes. This leads to defective connective tissue formation and increases sensitivity to physical stress and the risk of injury. Active magnesium participates in almost all biochemical reactions of connective tissue metabolism, and the impossibility of its synthesis in the body requires sufficient intake of this element with food and water. In the case of moderate-to-severe magnesium deficiency, it is pathogenetically reasonable to prescribe magnesium supplementation, which should take into account comorbidities, severity of deficiency, and age. Conclusion: Regular therapy with magnesium preparations helps to improve the mechanical properties of connective tissues, prevent the progression of dysplastic disorders, reduce the risk of injury, and maintain health during physical exercise. [ABSTRACT FROM AUTHOR]

Chondrosarcoma is a malignant bone tumor that emerges from abnormalities in cartilaginous tissue and is related with lung metastases. Nicotinamide phosphoribosyltransferase (NAMPT) is an adipocytokine reported to enhance tumor metastasis. Our results from clinical samples and the Gene Expression Omnibus data set reveal that NAMPT levels are markedly higher in chondrosarcoma patients than in normal individuals. NAMPT stimulation significantly increased lysyl oxidase (LOX) production in chondrosarcoma cells. Additionally, NAMPT increased LOX‐dependent cell migration and invasion in chondrosarcoma by suppressing miR‐26b‐5p generation through the c‐Src and Akt signaling pathways. Overexpression of NAMPT promoted chondrosarcoma metastasis to the lung in vivo. Furthermore, knockdown of LOX counteracted NAMPT‐facilitated metastasis. Thus, the NAMPT/LOX axis presents a novel target for treating the metastasis of chondrosarcoma. [ABSTRACT FROM AUTHOR]

This document, titled "Oxidative Stress: The Hidden Catalyst Fueling Atherosclerosis and Cardiovascular Disease," explores the role of oxidative stress in the development and progression of atherosclerosis, a condition characterized by inflammation of arterial vessels that can lead to serious cardiovascular outcomes. The article discusses various risk factors for atherosclerosis, such as smoking, dyslipidemia, obesity, hypertension, and diabetes, which contribute to endothelial dysfunction and the formation of atherosclerotic plaques. It also highlights the role of oxidative stress in this process, including the production of reactive oxygen species (ROS) and the damage they can cause to cells and tissues. The document presents several studies that investigate the impact of oxidative stress on atherosclerosis and potential therapeutic approaches to modulate this pathway. However, it acknowledges that there are other mechanisms and pathways involved in atherosclerosis that were not covered in this special issue. The article concludes by emphasizing the need for further research, particularly larger human studies and randomized controlled trials, to fully understand the clinical impact of antioxidant therapies in atherosclerosis and its complications. [Extracted from the article]

Background: Despite the available treatments, pulmonary arterial hypertension (PAH) prognosis is poor. Objectives: We aimed to investigate the effects of the alamandine (ALA), melatonin (MEL), and ALA + MEL in PAH. Methods: The rats were randomly divided into Control (n = 10), monocrotaline (MCT) (n = 12), ALA (n = 12), MEL (n = 12), and ALA + MEL (n = 12) groups. PAH was induced by MCT. The ALA, MEL, and ALA + MEL groups received 50 μg/kg/day ALA, 10 mg/kg/day MEL, and ALA + MEL, respectively, for 35 days. Echocardiographic and hemodynamic measurements and tissue analyses (morphometric, histopathological, ELISA, and western blot) were performed. Results: Monotherapies, especially MEL, reduced the right ventricular (RV) systolic pressure. Only MEL increased the pulmonary artery acceleration time. MCT increased the RV/left ventricle (LV) + interventricular septum (IVS) ratio. While ALA and ALA + MEL slightly decreased the RV/(LV + IVS), MEL significantly restored it. MCT increased the tunica intima‐media (TIM) thickness, PCNA and α‐SMA of pulmonary arterioles, histopathological score (HS) (inflammatory infiltration etc.) of the lung, and RV. All treatments reduced the TIM thickness (especially MEL), PCNA, and α‐SMA. All treatments significantly decreased the HS of the lung; however, MEL and ALA + MEL produced greater benefits. All treatments attenuated the HS of RV. MCT caused a significant increase in lung lysyl oxidase (LOX) activity. All treatments restored the LOX; however, MEL and ALA + MEL provided greater improvement. While lung Nrf‐2 was increased in MCT‐treated rats, MEL reduced it. Conclusion: ALA, MEL, and ALA + MEL attenuate PAH and protect RV via antiproliferative, anti‐remodeling, antihypertrophic, anti‐inflammatory, and free radical scavenging (only MEL) capabilities. Overall, MEL produced the best outcomes. [ABSTRACT FROM AUTHOR]

Immune checkpoint therapy has limited efficacy for patients with bone-metastatic castration-resistant prostate cancer (bmCRPC). To improve immunotherapy for bmCRPC, we aimed to identify the mechanism of bmCRPC-induced changes in the immune microenvironment. Among bmCRPC patients, higher levels of a 32-gene M2-like macrophage signature in bone metastasis samples correlated with shorter overall survival. Immunohistochemistry showed that CD206-positive (CD206+) macrophages were enriched in bmCRPC bone biopsy specimens compared with primary tumors or lymph node metastases. In preclinical osteogenic prostate cancer (Pca) xenograft models, CD206+ macrophages were recruited to areas with tumor-induced bone. RNA sequencing (RNAseq) analysis showed higher expression of an M2-like gene signature, with activated canonical and noncanonical Wnt pathways, in tumor-associated macrophages isolated from osteogenic tumors (bone-TAMs) than in TAMs isolated from nonosteogenic tumors (ctrl-TAMs). Mechanistic studies showed that endothelial cells (ECs) that had undergone EC-to-osteoblast (EC-to-OSB) transition, the precursors of tumor-induced OSBs, produced paracrine factors, including Wnts, CXCL14, and lysyl oxidase, which induced M2 polarization and recruited M2-like TAMs to the bone-tumor microenvironment (bone-TME). Bone-TAMs suppressed CD8+ T cells' proliferation and cytolytic activity, and these effects were partially reversed by treating bone-TAMs with Wnt inhibitors. Genetic or pharmacological inhibition of Pca-induced EC-to-OSB transition reduced the levels of M2-like macrophages in osteogenic tumors. Our study demonstrates that Pca-induced EC-to-OSB transition drives immunosuppression in the bone-TME, suggesting that therapies that reduce Pca-induced bone formation may improve immunotherapeutic outcomes for bmCRPC. [ABSTRACT FROM AUTHOR]

Chronic liver injury leads to decreased liver function and increased fibrosis. Fibrosis is not only associated with the development of portal hypertension and carcinogenesis, but with the occurrence of events and a poor prognosis, highlighting the importance of non‐invasive fibrosis assessment in patients. In the present study, we searched for markers related to liver fibrosis via proteomic analysis of small extracellular vesicles (sEVs). In the discovery cohort, proteomic analysis was carried out in the sEVs extracted from the sera of 5 patients with decompensated cirrhosis, 5 patients with compensated cirrhosis, and 5 controls without liver disease. Interestingly, in this cohort, fibulin‐4 was significantly associated with cirrhosis while in the validation cohort [formed by 191 patients: 7 patients without disease, 16 patients without liver disease (other diseases), 38 patients with chronic liver disease (CLD), 75 patients with cirrhosis of Child–Pugh class A (36 without hepatocellular carcinoma [HCC], 29 with HCC), and 65 patients with cirrhosis of Child–Pugh class B–C (39 without HCC, 26 with HCC)], fibulin‐4/CD9 levels increased with cirrhosis progression. Furthermore, the fibulin‐4/CD9 ratio was significantly higher in patients with varices. Immunostaining also revealed strong fibulin‐4 expression in cholangiocytes within the fibrous areas and mesothelial cells in liver tissue blood vessels. Taken together, our results suggest that fibulin‐4, essential for lysyl oxidase activation, might be a new liver fibrosis marker found in the sEVs of patients with cirrhosis. [ABSTRACT FROM AUTHOR]

Background: Lysyl oxidase enzymes (LOXs), as extracellular matrix (ECM) protein regulators, play vital roles in tumor progression by remodeling the tumor microenvironment. However, their roles in glioblastoma (GBM) have not been fully elucidated. Methods: The genetic alterations and prognostic value of LOXs were investigated via cBioPortal. The correlations between LOXs and biological functions/molecular tumor subtypes were explored in The Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA). After Kaplan‒Meier and Cox survival analyses, a Loxl1-based nomogram and prognostic risk score model (PRSM) were constructed and evaluated by time-dependent receiver operating characteristic curves, calibration curves, and decision curve analyses. Tumor enrichment pathways and immune infiltrates were explored by single-cell RNA sequencing and TIMER. Loxl1-related changes in tumor viability/proliferation and invasion were further validated by CCK-8, western blot, wound healing, and Transwell invasion assays. Results: GBM patients with altered LOXs had poor survival. Upregulated LOXs were found in IDH1-wildtype and mesenchymal (not Loxl1) GBM subtypes, promoting ECM receptor interactions in GBM. The Loxl1-based nomogram and the PRSM showed high accuracy, reliability, and net clinical benefits. Loxl1 expression was related to tumor invasion and immune infiltration (B cells, neutrophils, and dendritic cells). Loxl1 knockdown suppressed GBM cell proliferation and invasion by inhibiting the EMT pathway (through the downregulation of N-cadherin/Vimentin/Snai1 and the upregulation of E-cadherin). Conclusion: The Loxl1-based nomogram and PRSM were stable and individualized for assessing GBM patient prognosis, and the invasive role of Loxl1 could provide a promising therapeutic strategy. [ABSTRACT FROM AUTHOR]

Background: Triple-negative breast cancer (TNBC) cells are a highly formidable cancer to treat. Nonetheless, by continued investigation into the molecular biology underlying the complex regulation of TNBC cell activity, vulnerabilities can be exposed as potential therapeutic targets at the molecular level. We previously revealed that lysyl oxidase-like 4 (LOXL4) promotes the invasiveness of TNBC cells via cell surface annexin A2 as a novel binding substrate of LOXL4, which promotes the abundant localization of integrin-b1 at the cancer plasma membrane. However, it has yet to be uncovered how the LOXL4-mediated abundance of integrin-b1 hastens the invasive outgrowth of TNBC cells at the molecular level. Methods: LOXL4-overexpressing stable clones were established from MDA-MB231 cells and subjected to molecular analyses, real-time qPCR and zymography to clarify their invasiveness, signal transduction, and matrix metalloprotease (MMP) activity, respectively. Results: Our results show that LOXL4 potently promotes the induction of matrix metalloprotease 9 (MMP9) via activation of nuclear factor-kB (NF-kB). Our molecular analysis revealed that TNF receptor-associated factor 4 (TRAF4) and TGF-b activated kinase 1 (TAK1) were required for the activation of NF-kB through Ikb kinase kinase (IKKa/b) phosphorylation. Conclusion: Our results demonstrate that the newly identified LOXL4-mediated axis, integrin-b1-TRAF4-TAK1-IKKa/b-Ikba-NF-kB-MMP9, is crucial for TNBC cell invasiveness. [ABSTRACT FROM AUTHOR]

Oxidation of histone H3 at lysine 4 (H3K4ox) is catalyzed by lysyl oxidase homolog 2 (LOXL2). This histone modification is enriched in heterochromatin in triple‐negative breast cancer (TNBC) cells and has been linked to the maintenance of compacted chromatin. However, the molecular mechanism underlying this maintenance is still unknown. Here, we show that LOXL2 interacts with RuvB‐Like 1 (RUVBL1), RuvB‐Like 2 (RUVBL2), Actin‐like protein 6A (ACTL6A), and DNA methyltransferase 1associated protein 1 (DMAP1), a complex involved in the incorporation of the histone variant H2A.Z. Our experiments indicate that this interaction and the active form of RUVBL2 are required to maintain LOXL2‐dependent chromatin compaction. Genome‐wide experiments showed that H2A.Z, RUVBL2, and H3K4ox colocalize in heterochromatin regions. In the absence of LOXL2 or RUVBL2, global levels of the heterochromatin histone mark H3K9me3 were strongly reduced, and the ATAC‐seq signal in the H3K9me3 regions was increased. Finally, we observed that the interplay between these series of events is required to maintain H3K4ox‐enriched heterochromatin regions, which in turn is key for maintaining the oncogenic properties of the TNBC cell line tested (MDA‐MB‐231). [ABSTRACT FROM AUTHOR]

Background. Proliferative diabetic retinopathy (PDR) is a major cause of irreversible blindness in the working age population. The dysfunction of retinal vascular endothelial cells (RVECs) is the primary cause of PDR. Extracellular matrix (ECM) accumulation promotes intracellular signaling required for RVEC proliferation, migration, survival, and tube morphogenesis. Objectives. This study aimed to investigate the role of lysyl oxidase (LOX) in the cellular function of RVECs and PDR pathogenesis and to identify the underlying mechanisms. Materials and methods: Protein expression was determined with western blot. The interaction between LOX and elastin (ELN) was detected using a co-immunoprecipitation (Co-IP) assay, and the Cell Counting Kit-8 (CCK-8) assay evaluated cell viability. A colony formation assay was employed to assess the proliferation of human RVECs (hRVECs), and a transwell assay to determine their migration ability. Streptozotocin was used to establish PDR in mice in vivo. A histological analysis was conducted using hematoxylin and eosin (H&E) staining. Results: The results showed that LOX was overexpressed in PDR patients. The LOX knockdown suppressed ECM formation and hRVEC proliferation and migration. Additionally, LOX upregulated ELN expression. However, overexpressed ELN promoted hRVEC proliferation and migration. In vivo experiments showed that curcuminmediated LOX deficiency restored retinal tissue structure. Conclusions. The LOX-knockdown suppressed ECM formation and hRVEC proliferation and migration by inactivating ELN. Therefore, LOX/ELN signaling may be a potential PDR biomarker. [ABSTRACT FROM AUTHOR]

Collagen crosslinking, mediated by lysyl oxidase, is an adaptive mechanism of the cardiac repair process initiated by cardiac fibroblasts postmyocardial injury. However, excessive crosslinking leads to cardiac wall stiffening, which impairs the contractile properties of the left ventricle and leads to heart failure. In this study, we investigated the role of periostin, a matricellular protein, in the regulation of lysyl oxidase in cardiac fibroblasts in response to angiotensin II and TGFβ1. Our results indicated that periostin silencing abolished the angiotensin II and TGFβ1‐mediated upregulation of lysyl oxidase. Furthermore, the attenuation of periostin expression resulted in a notable reduction in the activity of lysyl oxidase. Downstream of periostin, ERK1/2 MAPK signaling was found to be activated, which in turn transcriptionally upregulates the serum response factor to facilitate the enhanced expression of lysyl oxidase. The periostin‐lysyl oxidase association was also positively correlated in an in vivo rat model of myocardial infarction. The expression of periostin and lysyl oxidase was upregulated in the collagen‐rich fibrotic scar tissue of the left ventricle. Remarkably, echocardiography data showed a reduction in the left ventricular wall movement, ejection fraction, and fractional shortening, indicative of enhanced stiffening of the cardiac wall. These findings shed light on the mechanistic role of periostin in the collagen crosslinking initiated by activated cardiac fibroblasts. Our findings signify periostin as a possible therapeutic target to reduce excessive collagen crosslinking that contributes to the structural remodeling associated with heart failure. Significance statement: Excessive collagen crosslinking mediated by lysyl oxidase (LOX) alters the mechanical properties of the cardiac wall following myocardial injury. In our study, we identified a novel regulatory mechanism by which periostin mediates LOX via activation of the ERK1/2 MAPK pathway and transcriptional activation of serum response factor in angiotensin II and TGFβ1‐stimulated cardiac fibroblasts. In addition, we observed a positive correlation between periostin and LOX in the infarcted scar of an in vivo rat model of myocardial infarction. These findings provide valuable insights into the intricate molecular mechanisms contributing to the stiffening of the cardiac wall and periostin as a possible therapeutic target to reduce excessive collagen crosslinking that contributes to the structural remodeling associated with heart failure. [ABSTRACT FROM AUTHOR]

Background: Airway epithelium is an important component of airway structure and the initiator of airway remodeling in asthma. The changes of extracellular matrix (ECM), such as collagen deposition and structural disturbance, are typical pathological features of airway remodeling. Thus, identifying key mediators that derived from airway epithelium and capable of modulating ECM may provide valuable insights for targeted therapy of asthma. Methods: The datasets from Gene Expression Omnibus database were analyzed to screen differentially expressed genes in airway epithelium of asthma. We collected bronchoscopic biopsies and serum samples from asthmatic and healthy subjects to assess lysyl oxidase like 2 (LOXL2) expression. RNA sequencing and various experiments were performed to determine the influences of LOXL2 knockdown in ovalbumin (OVA)-induced mouse models. The roles and mechanisms of LOXL2 in bronchial epithelial cells were explored using LOXL2 small interfering RNA, overexpression plasmid and AKT inhibitor. Results: Both bioinformatics analysis and further experiments revealed that LOXL2 is highly expressed in airway epithelium of asthmatics. In vivo, LOXL2 knockdown significantly inhibited OVA-induced ECM deposition and epithelial-mesenchymal transition (EMT) in mice. In vitro, the transfection experiments on 16HBE cells demonstrated that LOXL2 overexpression increases the expression of N-cadherin and fibronectin and reduces the expression of E-cadherin. Conversely, after silencing LOXL2, the expression of E-cadherin is up-regulated. In addition, the remodeling and EMT process that induced by transforming growth factor-β1 could be enhanced and weakened after LOXL2 overexpression and silencing in 16HBE cells. Combining the RNA sequencing of mouse lung tissues and experiments in vitro, LOXL2 was involved in the regulation of AKT signaling pathway. Moreover, the treatment with AKT inhibitor in vitro partially alleviated the consequences associated with LOXL2 overexpression. Conclusions: Taken together, the results demonstrated that epithelial LOXL2 plays a role in asthmatic airway remodeling partly via the AKT signaling pathway and highlighted the potential of LOXL2 as a therapeutic target for airway remodeling in asthma. [ABSTRACT FROM AUTHOR]

This article discusses the potential use of thiamine and essential fatty acids (EFAs) in the treatment of sepsis. Thiamine is known to play a key role in cellular metabolism and energy production, but its effectiveness in septic shock therapy has yielded mixed results. The author suggests that the metabolism of EFAs, which are converted into anti-inflammatory and pro-inflammatory compounds, may be critical in regulating inflammation and immune response in sepsis. The article proposes that a combination of vitamins B1, B6, B12, vitamin C, EFAs, and corticosteroids could be useful in preventing and managing sepsis. [Extracted from the article]

Inspired by the enzyme lysyl oxidase, which selectively converts the side chain of lysine into allysine, an aldehyde‐containing post‐translational modification, we report herein the first chemical method for the synthesis of allysine by selective oxidation of dimethyl lysine. This approach is highly chemoselective for dimethyl lysine on proteins. We highlight the utility of this biomimetic approach for generating aldehydes in a variety of pharmaceutically active linear and cyclic peptides at a late stage for their diversification with various affinity and fluorescent tags. Notably, we utilized this approach for generating small‐molecule aldehydes from the corresponding tertiary amines. We further demonstrated the potential of this approach in generating cellular models for studying allysine‐associated diseases. [ABSTRACT FROM AUTHOR]

Inspired by the enzyme lysyl oxidase, which selectively converts the side chain of lysine into allysine, an aldehyde‐containing post‐translational modification, we report herein the first chemical method for the synthesis of allysine by selective oxidation of dimethyl lysine. This approach is highly chemoselective for dimethyl lysine on proteins. We highlight the utility of this biomimetic approach for generating aldehydes in a variety of pharmaceutically active linear and cyclic peptides at a late stage for their diversification with various affinity and fluorescent tags. Notably, we utilized this approach for generating small‐molecule aldehydes from the corresponding tertiary amines. We further demonstrated the potential of this approach in generating cellular models for studying allysine‐associated diseases. [ABSTRACT FROM AUTHOR]

Pancreatic fibrosis (PF) is primarily characterized by aberrant production and degradation modes of extracellular matrix (ECM) components, resulting from the activation of pancreatic stellate cells (PSCs) and the pathological cross‐linking of ECM mediated by lysyl oxidase (LOX) family members. The excessively deposited ECM increases matrix stiffness, and the over‐accumulated reactive oxygen species (ROS) induces oxidative stress, which further stimulates the continuous activation of PSCs and advancing PF; challenging the strategy toward normalizing ECM homeostasis for the regression of PF. Herein, ROS‐responsive and Vitamin A (VA) decorated micelles (named LR‐SSVA) to reverse the imbalanced ECM homeostasis for ameliorating PF are designed and synthesized. Specifically, LR‐SSVA selectively targets PSCs via VA, thereby effectively delivering siLOXL1 and resveratrol (RES) into the pancreas. The ROS‐responsive released RES inhibits the overproduction of ECM by eliminating ROS and inactivating PSCs, meanwhile, the decreased expression of LOXL1 ameliorates the cross‐linked collagen for easier degradation by collagenase which jointly normalizes ECM homeostasis and alleviates PF. This research shows that LR‐SSVA is a safe and efficient ROS‐response and PSC‐targeted drug‐delivery system for ECM normalization, which will propose an innovative and ideal platform for the reversal of PF. [ABSTRACT FROM AUTHOR]

Introduction: Duchenne muscular dystrophy (DMD) is a fatal striated muscle degenerative disease. DMD is caused by loss of dystrophin protein, which results in sarcolemmal instability and cycles of myofiber degeneration and regeneration. Pathology is exacerbated by overactivation of infiltrating immune cells and fibroblasts, which leads to chronic inflammation and fibrosis. Mineralocorticoid receptors (MR), a type of nuclear steroid hormone receptors, are potential therapeutic targets for DMD. MR antagonists show clinical efficacy on DMD cardiomyopathy and preclinical efficacy on skeletal muscle in DMD models. Methods: We have previously generated myofiber and myeloid MR knockout mouse models to dissect cell-specific functions of MR within dystrophic muscles. Here, we compared skeletal muscle gene expression from both knockouts to further define cell-type specific signaling downstream from MR. Results: Myeloid MR knockout increased proinflammatory and profibrotic signaling, including numerous myofibroblast signature genes. Tenascin C was the most highly upregulated fibrotic gene in myeloid MR-knockout skeletal muscle and is a component of fibrosis in dystrophic skeletal muscle. Surprisingly, lysyl oxidase (Lox), canonically a collagen crosslinker, was increased in both MR knockouts, but did not localize to fibrotic regions of skeletal muscle. Lox localized within myofibers, including only a region of quadriceps muscles. Lysyl oxidase like 1 (Loxl1), another Lox family member, was increased only in myeloid MR knockout muscle and localized specifically to fibrotic regions. Discussion: This study suggests that MR signaling in the dystrophic muscle microenvironment involves communication between contributing cell types and modulates inflammatory and fibrotic pathways in muscle disease. [ABSTRACT FROM AUTHOR]

Purpose: Considering inhibition of pre-adipocyte cells differentiation in adipose tissue fibrosis, we aimed to explore whether Sirt1 and Hif-1α in pre-adipocytes have a significant effect on fibrotic gene expression. Methods: 3T3-L1 pre-adipocytes were transfected with SIRT1-specific siRNA, confirmed by real-time polymerase chain reaction (RT-PCR) and western blotting. Additionally, cells were treated with varying concentrations of resveratrol and sirtinol as the activator and inhibitor of Sirt1, respectively. Involvement of Hif-1α was evaluated by treatment with echinomycin. Subsequently, we assessed the gene and protein expressions related to fibrosis in the extracellular matrix of adipose tissue, including collagen VI (Col VI), lysyl oxidase (Lox), matrix metalloproteinase-2 (Mmp-2), Mmp-9, and osteopontin (Opn) in pre-adipocytes through RT-PCR and western blot. Results: The current study demonstrated that Sirt1 knockdown and reduced enzyme activity significantly increased the expression of Col VI, Lox, Mmp-2, Mmp-9, and Opn genes in the treated 3T3-L1 cells compared to the control group. Interestingly, resveratrol significantly decreased the gene expression related to the fibrosis pathway. Inhibition of Hif-1α by echinomycin led to a significant reduction in Col VI, Mmp-2, and Mmp-9 gene expression in the treated group compared to the control. Conclusion: This study highlights that down-regulation of Sirt1 might be a predisposing factor in the emergence of adipose tissue fibrosis by enhancing the expression of extracellular matrix (ECM) components. Activation of Sirt1, similar to suppressing of Hif-1α in pre-adipocytes may be a beneficial approach for attenuating fibrotic gene expression. [ABSTRACT FROM AUTHOR]

Regenerative medicine is an interdisciplinary field aiming at restoring pathologically damaged tissues and whole organs by cell transplantation in combination with proper supporting scaffolds. Gelatine-based ones are very attractive due to their biocompatibility, rapid biodegradability, and lack of immunogenicity. Gelatine-based composite hydrogels, containing strengthening agents to improve their modest mechanical properties, have been demonstrated to act as extracellular matrices (ECMs), thus playing a critical role in "organ manufacturing". Inspired by the lysyl oxidase (LO)-mediated process of crosslinking, which occurs in nature to reinforce collagen, we have recently developed a versatile protocol to crosslink gelatine B (Gel B) in the presence or absence of LO, using properly synthesized polystyrene- and polyacrylic-based copolymers containing the amine or aldehyde groups needed for crosslinking reactions. Here, following the developed protocol with slight modifications, we have successfully crosslinked Gel B in different conditions, obtaining eight out of nine compounds in high yield (57–99%). The determined crosslinking degree percentage (CP%) evidenced a high CP% for compounds obtained in presence of LO and using the styrenic amine-containing (CP5/DMAA) and acrylic aldehyde-containing (CPMA/DMAA) copolymers as crosslinking agents. ATR-FTIR analyses confirmed the chemical structure of all compounds, while optical microscopy demonstrated cavernous, crater-like, and labyrinth-like morphologies and cavities with a size in the range 15–261 µm. An apparent density in the range 0.10–0.45 g/cm3 confirmed the aerogel-like structure of most samples. Although the best biodegradation profile was observed for the sample obtained using 10% CP5/DMAA (M3), high swelling and absorption properties, high porosity, and good biodegradation profiles were also observed for samples obtained using the 5–10% CP5/DMAA (M4, 5, 6) and 20% CPMA/DMAA (M9) copolymers. Collectively, in this work of synthesis and physicochemical characterization, new aerogel-like composites have been developed and, based on their characteristics, which fit well within the requirements for TE, five candidates (M3, M4, M5, M6, and M9) suitable for future biological experiments on cell adhesion, infiltration and proliferation, to confirm their effective functioning, have been identified. [ABSTRACT FROM AUTHOR]

Background/aim: Our recent study revealed that the expression of lipoxygenase (LOX) and cyclooxygenase (COX) enzymes in the hypothalamus is activated by nesfatin-1, leading to the liberation of leukotrienes and prostaglandins (PG), respectively. Moreover, our prior report explained that intracerebroventricular (ICV) nesfatin-1 treatment triggers cardiovascular responses mediated by central LOX and COX enzymes. Building upon our prior reports, the present investigation sought to clarify the role of cardiovascularly active central COX products, such as thromboxane (TX) A2, PGF2α, PGE, and PGD, in orchestrating nesfatin-1-evoked reactions in mean arterial pressure (MAP) and heart rate (HR). Materials and methods: The Sprague Dawley rats, which had guide cannula in the lateral ventricle for intracerebroventricular (ICV) injections and catheter in arteria femoralis for monitoring MAP and HR, were underwent central pretreatment with furegrelate (the TXA2 synthase inhibitor), PGF2α-dimethylamine (PGF2α-DA, the PGF2α receptor antagonist), or AH6809 (the PGE and PGD receptor antagonist), 5 min prior to ICV nesfatin-1 administration. The cardiovascular parameters were observed and recorded for 60 min posttreatment Results: Nesfatin-1 induced cardiovascular responses in rats leading to pressor effect in MAP, and tachycardia following bradycardia in HR. Interestingly, ICV furegrelate, PGF2α-DA, or AH6809 pretreatment partially mitigated the cardiovascular effects revealed by nesfatin-1. Conclusion: The findings illuminate the role of nesfatin-1 in modulating MAP and HR through the central activation of specifically TXA2, PGF2α, PGE, and PGD from COX metabolites. Additionally, the study may also suggest the potential involvement of other central COX or LOX metabolites beyond these COX metabolites in mediating the cardiovascular effects produced by nesfatin-1. [ABSTRACT FROM AUTHOR]

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Lysyl oxidase (LOX)-mediated extracellular matrix crosslinking modulates calcification in atherosclerosis and aortic valve disease; however, this enzyme also induces oxidative stress. We addressed the contribution of LOX-dependent oxidative stress to cardiovascular calcification. LOX is upregulated in human-calcified atherosclerotic lesions and atheromas from atherosclerosis-challenged LOX transgenic mice (TgLOXVSMC) and colocalized with a marker of oxidative stress (8-oxo-deoxyguanosine) in vascular smooth muscle cells (VSMCs). Similarly, in calcific aortic valves, high LOX expression was detected in valvular interstitial cells (VICs) positive for 8-oxo-deoxyguanosine, while LOX and LOXL2 expression correlated with osteogenic markers (SPP1 and RUNX2) and NOX2. In human VICs, mito-TEMPO and TEMPOL attenuated the increase in superoxide anion levels and the mineralization induced by osteogenic media (OM). Likewise, in OM-exposed VICs, β-aminopropionitrile (a LOX inhibitor) ameliorated both oxidative stress and calcification. Gain- and loss-of-function approaches in VICs demonstrated that while LOX silencing negatively modulates oxidative stress and calcification induced by OM, lentiviral LOX overexpression exacerbated oxidative stress and VIC calcification, effects that were prevented by mito-TEMPO, TEMPOL, and β-aminopropionitrile. Our data indicate that LOX-induced oxidative stress participates in the procalcifying effects of LOX activity in ectopic cardiovascular calcification, and highlight the multifaceted role played by LOX isoenzymes in cardiovascular diseases. [ABSTRACT FROM AUTHOR]

The lipoxygenase pathway has a significant influence on the composition of the volatile components of virgin olive oil (VOO). In this work, the influence of the maturity index (MI) on the activity of the lipoxygenase enzyme (LOX) in the fruits of the autochthonous Dalmatian olive cultivars Oblica, Levantinka and Lastovka was studied. The analysis of the primary oxidation products of linoleic acid in the studied cultivars showed that LOX synthesises a mixture of 9- and 13-hydroperoxides of octadecenoic acid in a ratio of about 1:2, which makes it a non-traditional plant LOX. By processing the fruits of MI~3, we obtained VOOs with the highest concentration of desirable C6 volatile compounds among the cultivars studied. We confirmed a positive correlation between MI, the enzyme activity LOX and the concentration of hexyl acetate and hexanol in cultivars Oblica and Lastovka, while no positive correlation with hexanol was observed in the cultivar Levantinka. A significant negative correlation was found between total phenolic compounds in VOO and LOX enzyme activity, followed by an increase in the MI of fruits. This article contributes to the selection of the optimal harvest time for the production of VOOs with the desired aromatic properties and to the knowledge of the varietal characteristics of VOOs. [ABSTRACT FROM AUTHOR]

Background: Our earlier research revealed that the secreted lysyl oxidase-like 4 (LOXL4) that is highly elevated in triple-negative breast cancer (TNBC) acts as a catalyst to lock annexin A2 on the cell membrane surface, which accelerates invasive outgrowth of the cancer through the binding of integrin-β1 on the cell surface. However, whether this machinery is subject to the LOXL4-mediated intrusive regulation remains uncertain. Methods: Cell invasion was assessed using a transwell-based assay, protein-protein interactions by an immunoprecipitation-Western blotting technique and immunocytochemistry, and plasmin activity in the cell membrane by gelatin zymography. Results: We revealed that cell surface annexin A2 acts as a receptor of plasminogen via interaction with S100A10, a key cell surface annexin A2-binding factor, and S100A11. We found that the cell surface annexin A2/ S100A11 complex leads to mature active plasmin from bound plasminogen, which actively stimulates gelatin digestion, followed by increased invasion. Conclusion: We have refined our understanding of the role of LOXL4 in TNBC cell invasion: namely, LOXL4 mediates the upregulation of annexin A2 at the cell surface, the upregulated annexin 2 binds S100A11 and S100A10, and the resulting annexin A2/S100A11 complex acts as a receptor of plasminogen, readily converting it into active-form plasmin and thereby enhancing invasion. [ABSTRACT FROM AUTHOR]

Environmental tobacco smoke (ETS) is known to cause lung inflammatory and injurious responses. Smoke exposure is associated with the pathobiology related to lung fibrosis, whereas the mechanism that ETS exposure augments pulmonary fibrogenesis is unclear. We hypothesized that ETS exposure could exacerbate fibrotic responses via collagen dynamic dysregulation and complement activation. C57BL/6J and p16-3MR mice were exposed to ETS followed by bleomycin administration. ETS exposure exacerbated bleomycin-induced collagen and lysyl oxidase overexpression in the fibrotic lesion. ETS exposure also led to augmented bleomycin-induced upregulation of C3 and C3AR, which are pro-fibrotic markers. Moreover, overexpressed collagens and C3 levels were highly significant in males than females. The old mice (17 months old) were exposed to ETS and treated with bleomycin to induce fibrogenesis which is considered as an aging-associated disease. Fewer gene and protein dysregulations trends were identified between ETS exposure with the bleomycin group and the bleomycin alone group in old mice. Based on our findings, we suggested that ETS exposure increases the risk of developing severe lung fibrotic responses via collagen overexpression and lysyl oxidase-mediated collagen stabilization in the fibrotic lesion, and potentially affected the complement system activation induced by bleomycin. Further, male mice were more susceptible than females during fibrogenesis exacerbation. Thus ETS and bleomycin induced lung fibrotic changes via collagen-lysyl oxidase in an age-dependent mechanism. [ABSTRACT FROM AUTHOR]

Idiopathic pulmonary fibrosis (IPF) is a devastating interstitial lung disease characterized by the relentless deposition of extracellular matrix (ECM), causing lung distortions and dysfunction. Animal models of human IPF can provide great insight into the mechanistic pathways underlying disease progression and a means for evaluating novel therapeutic approaches. In this study, we describe the effect of bleomycin concentration on disease progression in the classical rat bleomycin model. In a dose–response study (1.5, 2, 2.5 U/kg i.t), we characterized lung fibrosis at day 14 after bleomycin challenge using endpoints including clinical signs, inflammatory cell infiltration, collagen content, and bronchoalveolar lavage fluid-soluble profibrotic mediators. Furthermore, we investigated fibrotic disease progression after 2 U/kg i.t. bleomycin administration at days 3, 7, and 14 by quantifying the expression of clinically relevant signaling molecules and pathways, epithelial mesenchymal transition (EMT) biomarkers, ECM components, and histopathology of the lung. A single bleomycin challenge resulted in a progressive fibrotic response in rat lung tissue over 14 days based on lung collagen content, histopathological changes, and modified Ashcroft score. The early fibrogenesis phase (days 3 to 7) is associated with an increase in profibrotic mediators including TGFβ1, IL6, TNFα, IL1β, CINC1, WISP1, VEGF, and TIMP1. In the mid and late fibrotic stages, the TGFβ/Smad and PDGF/AKT signaling pathways are involved, and clinically relevant proteins targeting galectin-3, LPA1, transglutaminase-2, and lysyl oxidase 2 are upregulated on days 7 and 14. Between days 7 and 14, the expressions of vimentin and α-SMA proteins increase, which is a sign of EMT activation. We confirmed ECM formation by increased expressions of procollagen-1Aα, procollagen-3Aα, fibronectin, and CTGF in the lung on days 7 and 14. Our data provide insights on a complex network of several soluble mediators, clinically relevant signaling pathways, and target proteins that contribute to drive the progressive fibrotic phenotype from the early to late phase (active) in the rat bleomycin model. The framework of endpoints of our study highlights the translational value for pharmacological interventions and mechanistic studies using this model. [ABSTRACT FROM AUTHOR]

Background: Drug induced bile duct injury is a frequently observed clinical problem leading to a wide range of pathological features. During the past decades, several agents have been identified with various postulated mechanisms of bile duct damage, however, mostly still poorly understood. Methods: Here, we investigated the mechanisms of chlorpromazine (CPZ) induced bile duct injury using advanced in vitro cholangiocyte cultures. Intrahepatic cholangiocyte organoids (ICOs) were driven into mature cholangiocyte like cells (CLCs), which were exposed to CPZ under cholestatic or non-cholestatic conditions through the addition of a bile acid cocktail. Results: CPZ caused loss of monolayer integrity by reducing expression levels of tight junction protein 1 (TJP1), E-cadherin 1 (CDH1) and lysyl oxidase homolog 2 (LOXL2). Loss of zonula occuludens-1 (ZO-1) and E-cadherin was confirmed by immunostaining after exposure to CPZ and rhodamine-123 leakage further confirmed disruption of the cholangiocyte barrier function. Furthermore, oxidative stress seemed to play a major role in the early damage response by CPZ. The drug also decreased expression of three main basolateral bile acid transporters, ABCC3 (ATP binding cassette subfamily C member 3), SLC51A/B (solute carrier family 51 subunit alpha/beta) and multidrug resistance transporter ABCB1 (ATP binding cassette subfamily B member 1), thereby contributing to bile acid accumulation. CPZ did not induce an inflammatory response by itself, but addition of TNFα revealed a synergistic effect. Conclusion: These results show that ICOs present a model to identify toxic drugs affecting the bile ducts while providing mechanistic insights into hepatotoxicity. [ABSTRACT FROM AUTHOR]

In tissue engineering (TE), the support structure (scaffold) plays a key role necessary for cell adhesion and proliferation. The protein constituents of the extracellular matrix (ECM), such as collagen, its derivative gelatine, and elastin, are the most attractive materials as possible scaffolds. To improve the modest mechanical properties of gelatine, a strategy consists of crosslinking it, as naturally occurs for collagen, which is stiffened by the oxidative action of lysyl oxidase (LO). Here, a novel protocol to crosslink gelatine has been developed, not using the commonly employed crosslinkers, but based on the formation of imine bonds or on aldolic condensation reactions occurring between gelatine and properly synthesized copolymers containing amine residues via LO-mediated oxidation. Particularly, we first synthesized and characterized an amino butyl styrene monomer (5), its copolymers with dimethylacrylamide (DMAA), and its terpolymer with DMAA and acrylic acid (AA). Three acryloyl amidoamine monomers (11a–c) and their copolymers with DMAA were then prepared. A methacrolein (MA)/DMAA copolymer already possessing the needed aldehyde groups was finally developed to investigate the relevance of LO in the crosslinking process. Oxidation tests of amine copolymers with LO were performed to identify the best substrates to be used in experiments of gelatine reticulation. Copolymers obtained with 5, 11b, and 11c were excellent substrates for LO and were employed with MA/DMAA copolymers in gelatine crosslinking tests in different conditions. Among the amine-containing copolymers, that obtained with 5 (CP5/DMMA-43.1) afforded a material (M21) with the highest crosslinking percentage (71%). Cytotoxicity experiments carried out on two cell lines (IMR-32 and SH SY5Y) with the analogous (P5) of the synthetic constituent of M21 (CP5/DMAA) had evidenced no significant reduction in cell viability, but proliferation promotion, thus establishing the biocompatibility of M21 and the possibility to develop it as a new scaffold for TE, upon further investigations. [ABSTRACT FROM AUTHOR]

Objective: This study tested the hypothesis that limited subcutaneous adipose tissue (SAT) expansion represents a primary predisposition to the development of type 2 diabetes mellitus (T2DM), independent of obesity, and identified novel markers of SAT dysfunction in the inheritance of T2DM. Methods: First‐degree relatives (FDR) of T2DM patients (n = 19) and control individuals (n = 19) without obesity (fat mass < 25%) were cross‐sectionally compared. Body composition (bioimpedance, computed tomography) and insulin sensitivity (IS; oral glucose tolerance test, clamp) were measured. SAT obtained by needle biopsy was used to analyze adipocyte size, lipidome, mRNA expression, and inflammatory markers. Primary cultures of adipose precursors were analyzed for adipogenic capacity and metabolism. Results: Compared with control individuals, FDR individuals had lower IS and a higher amount of visceral fat. However, SAT‐derived adipose precursors did not differ in their ability to proliferate and differentiate or in metabolic parameters (lipolysis, mitochondrial oxidation). In SAT of FDR individuals, lipidomic and mRNA expression analysis revealed accumulation of triglycerides containing polyunsaturated fatty acids and increased mRNA expression of lysyl oxidase (LOX). These parameters correlated with IS, visceral fat accumulation, and mRNA expression of inflammatory and cellular stress genes. Conclusions: The intrinsic adipogenic potential of SAT is not affected by a family history of T2DM. However, alterations in LOX mRNA and polyunsaturated fatty acids in triacylglycerols are likely related to the risk of developing T2DM independent of obesity. [ABSTRACT FROM AUTHOR]

Simple Summary: Dietary lipid or oil sources play important roles in modulating growth, immunity and muscle quality in animals. The aim of the present study was to investigate the impact of fish oil (FO), soybean oil (SO), rapeseed oil (RO), peanut oil (PO) and lard oil (LO) on the growth, fish body composition, digestive ability, hematological parameters, serum biochemical indices, immune capability, inflammatory responses and muscle quality in juvenile largemouth bass. Compared with PO and LO, FO and RO showed improvements in weight gain, fatty acid profiles, digestive abilities, innate capabilities and muscle qualities (hardness, firmness and chewiness) with higher collagen synthesizing abilities. The results in this study could provide relative references for the application of dietary lipid sources in largemouth bass and other fish species. This study investigated the effects of fish oil (FO), soybean oil (SO), rapeseed oil (RO), peanut oil (PO) and lard oil (LO) on growth, immunity and muscle quality in juvenile largemouth bass. After 8 weeks, the results showed that FO and RO could increase weight gain and serum alkaline phosphatase and apelin values compared with LO (p < 0.05). Except lower crude lipid contents, higher amounts of n-3 polyunsaturated fatty acids (15.83% and 14.64%) were present in the dorsal muscle of the FO and RO groups. Meanwhile, FO and RO could heighten mRNA levels of immune defense molecules (lysozyme, hepcidin, and transforming growth factor β1) compared with PO (p < 0.05). While SO could increase potential inflammatory risk via rising counts of white blood cells, platelets, neutrophils and monocytes, and mRNA levels of interleukins (IL-1β, IL-8, IL-12 and IL-15), FO and RO could improve hardness, chewiness and springiness through increasing amounts of hydroxyproline, collagen and lysyl oxidase, and mRNA levels of collagen 1α2 and prolyl hydroxylase in the fish dorsal muscle. Moreover, FO and RO could improve firmness through increasing glycogen and glycogen synthase 1 levels when compared with LO (p < 0.05). Therefore, these results could provide dietary lipid source references during the feeding process of adult largemouth bass. [ABSTRACT FROM AUTHOR]

Hypoxia is a common feature of solid tumours affecting their biology and response to therapy. One of the main transcription factors activated by hypoxia is hypoxiainducible factor (HIF), which regulates the expression of genes involved in various aspects of tumourigenesis including proliferative capacity, angiogenesis, immune evasion, metabolic reprogramming, extracellular matrix (ECM) remodelling, and cell migration. This can negatively impact patient outcomes by inducing therapeutic resistance. The importance of hypoxia is clearly demonstrated by continued research into finding clinically relevant hypoxia biomarkers, and hypoxia-targeting therapies. One of the problems is the lack of clinically applicable methods of hypoxia detection, and lack of standardisation. Additionally, a lot of the methods of detecting hypoxia do not take into consideration the complexity of the hypoxic tumour microenvironment (TME). Therefore, this needs further elucidation as approximately 50% of solid tumours are hypoxic. The ECM is important component of the hypoxic TME, and is developed by both cancer associated fibroblasts (CAFs) and tumour cells. However, it is important to distinguish the different roles to develop both biomarkers and novel compounds. Fibronectin (FN), collagen (COL) and hyaluronic acid (HA) are important components of the ECM that create ECM fibres. These fibres are crosslinked by specific enzymes including lysyl oxidase (LOX) which regulates the stiffness of tumours and induces fibrosis. This is partially regulated by HIFs. The review highlights the importance of understanding the role of matrix stiffness in different solid tumours as current data shows contradictory results on the impact on therapeutic resistance. The review also indicates that further research is needed into identifying different CAF subtypes and their exact roles; with some showing pro-tumorigenic capacity and others having antitumorigenic roles. This has made it difficult to fully elucidate the role of CAFs within the TME. However, it is clear that this is an important area of research that requires unravelling as current strategies to target CAFs have resulted in worsened prognosis. The role of immune cells within the tumour microenvironment is also discussed as hypoxia has been associated with modulating immune cells to create an anti-tumorigenic environment. Which has led to the development of immunotherapies including PD-L1. These hypoxia-induced changes can confer resistance to conventional therapies, such as chemotherapy, radiotherapy, and immunotherapy. This review summarizes the current knowledge on the impact of hypoxia on the TME and its implications for therapy resistance. It also discusses the potential of hypoxia biomarkers as prognostic and predictive indictors of treatment response, as well as the challenges and opportunities of targeting hypoxia in clinical trials. [ABSTRACT FROM AUTHOR]

To investigate collagen I, collagen V, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), lysyl oxidase (LOX), transforming growth factor β1 (TGF-β1) and interleukin-6 (IL-6) expression in healthy and keratoconus human corneal fibroblasts (HCFs and KC-HCFs), 24 h after Rose Bengal photodynamic therapy (RB-PDT). HCFs were isolated from healthy human corneal donors (n = 5) and KC-HCFs from elective penetrating keratoplasties (n = 5). Both cell cultures underwent RB-PDT (0.001% RB concentration, 0.17 J/cm2 fluence) and 24 h later collagen I, collagen V, NF-κB, LOX, TGF-β1 and IL-6 mRNA and protein expression have been determined using qPCR and Western blot, IL-6 concentration in the cell culture supernatant by ELISA. TGF-β1 mRNA expression was significantly lower (p = 0.02) and IL-6 mRNA expression was significantly higher in RB-PDT treated HCFs (p = 0.01), than in HCF controls. COL1A1, COL5A1 and TGF-β1 mRNA expression was significantly lower (p = 0.04; p = 0.02 and p = 0.003) and IL-6 mRNA expression was significantly higher (p = 0.02) in treated KC-HCFs, than in KC-HCF controls. TGF-β1 protein expression in treated HCFs was significantly higher than in HCF controls (p = 0.04). IL-6 protein concentration in the HCF and KC-HCF culture supernatant after RB-PDT was significantly higher than in controls (p = 0.02; p = 0.01). No other analyzed mRNA and protein expression differed significantly between the RB-PDT treated and untreated groups. Our study demonstrates that RB-PDT reduces collagen I, collagen V and TGF-β1 mRNA expression, while increasing IL-6 mRNA and protein expression in KC-HCFs. In HCFs, RB-PDT increases TGF-β1 and IL-6 protein level after 24 h. [ABSTRACT FROM AUTHOR]

Vascular inflammation is known to cause degeneration of retinal capillaries in early diabetic retinopathy (DR), a major microvascular complication of diabetes. Past studies investigating these diabetes-induced retinal vascular abnormalities have focused primarily on the role of molecular or biochemical cues. Here we show that retinal vascular inflammation and degeneration in diabetes are also mechanically regulated by the increase in retinal vascular stiffness caused by overexpression of the collagen–cross-linking enzyme lysyl oxidase (LOX). Treatment of diabetic mice with LOX inhibitor β-aminopropionitrile (BAPN) prevented the increase in retinal capillary stiffness, vascular intracellular adhesion molecule-1 overexpression, and leukostasis. Consistent with these anti-inflammatory effects, BAPN treatment of diabetic mice blocked the upregulation of proapoptotic caspase-3 in retinal vessels, which concomitantly reduced retinal capillary degeneration, pericyte ghost formation, and the diabetes-induced loss of contrast sensitivity in these mice. Finally, our in vitro studies indicate that retinal capillary stiffening is sufficient to increase the adhesiveness and neutrophil elastase-induced death of retinal endothelial cells. By uncovering a link between LOX-dependent capillary stiffening and the development of retinal vascular and functional defects in diabetes, these findings offer a new insight into DR pathogenesis that has important translational potential. Article Highlights: The objective of this study was to determine whether retinal vascular inflammation and degeneration associated with early diabetic retinopathy are mechanically regulated by the increased stiffness of retinal capillaries. We provide the first direct evidence of retinal capillary stiffening in diabetes that is dependent on lysyl oxidase (LOX), promotes retinal vascular inflammation, and causes capillary degeneration by increasing retinal endothelial susceptibility to neutrophil elastase. We also show that pharmacological inhibition of LOX prevents the diabetes-induced loss of contrast sensitivity. These findings implicate LOX and capillary stiffening as new anti-inflammatory targets for the treatment of retinal vascular and functional defects associated with early diabetic retinopathy. [ABSTRACT FROM AUTHOR]

Melanoma is characterized by high metastatic potential favored by the epithelial-to-mesenchymal transition (EMT), leading melanoma cells to exhibit a spectrum of typical EMT markers. This study aimed to analyze the expression of EMT markers in A375 and BLM melanoma cell lines cultured in 2D monolayers and 3D spheroids using morphological and molecular methods. The expression of EMT markers was strongly affected by 3D arrangement and revealed a hybrid phenotype for the two cell lines. Indeed, although E-cadherin was almost undetectable in both A375 and BLM cells, cortical actin was detected in A375 2D monolayers and 3D spheroids and was strongly expressed in BLM 3D spheroids. The mesenchymal marker N-cadherin was significantly up-regulated in A375 3D spheroids while undetectable in BLM cells, but vimentin was similarly expressed in both cell lines at the gene and protein levels. This pattern suggests that A375 cells exhibit a more undifferentiated/mesenchymal phenotype, while BLM cells have more melanocytic/differentiated characteristics. Accordingly, the Zeb1 and 2, Slug, Snail and Twist gene expression analyses showed that they were differentially expressed in 2D monolayers compared to 3D spheroids, supporting this view. Furthermore, A375 cells are characterized by a greater invasive potential, strongly influenced by 3D arrangement, compared to the BLM cell line, as evaluated by SDS-zymography and TIMPs gene expression analysis. Finally, TGF-β1, a master controller of EMT, and lysyl oxidase (LOX), involved in melanoma progression, were strongly up-regulated by 3D arrangement in the metastatic BLM cells alone, likely playing a role in the metastatic phases of melanoma progression. Overall, these findings suggest that A375 and BLM cells possess a hybrid/intermediate phenotype in relation to the expression of EMT markers. The former is characterized by a more mesenchymal/undifferentiated phenotype, while the latter shows a more melanocytic/differentiated phenotype. Our results contribute to the characterization of the role of EMT in melanoma cells and confirm that a 3D cell culture model could provide deeper insight into our understanding of the biology of melanoma. [ABSTRACT FROM AUTHOR]

Background: Ehlers-Danlos syndrome Type IV (aka Vascular Ehlers Danlos, or vEDS) is a dominantly inherited mutation in the Collagen 3A1 gene (COL3A1). The disease is characterized by tissue friability and age-related susceptibility to arterial aneurysm, dissection and rupture as well as uterine and bowl tears. These clinical manifestations result in major surgical intervention and decreased life expectancy. Understanding how mutations in COL3A1 impact the structure and function of the extracellular matrix (ECM) is important to managing the disease and finding treatments. Results: Skin fibroblasts from vEDS subjects heterozygous for the p.G588S pathogenic variant in the COL3A1 gene and a normal individual were cultured and studied. Proteomics analysis identified dozens of upregulated proteins related to extracellular matrix dysregulation that is characteristic of fibrosis. Gene expression libraries from cultured primary fibroblasts were screened for messenger RNA (mRNA) markers of ECM degradation. The proteomics and targeted gene expression array results were largely consistent with dysregulation of the extracellular matrix in vEDS. The data show upregulation of multiple Collagen proteins and genes, other ECM components, and enzymes related to ECM processing and turn-over. vEDS fibroblasts expressed significantly more cross linked C-Telopeptide of Collagen III (CTXIII) than normal fibroblasts, indicative of Collagen III degradation and turn-over. Further, the expression and activity of Lysyl Oxidase (LOX), an enzyme that initiates covalent cross-linking of soluble collagen and elastin into protease resistant fibers, is elevated in vEDS fibroblasts compared to normal fibroblasts. Conclusion: Together, these findings suggest dysregulated ECM deposition and processing, reminiscent of a state of fibrosis. Therapeutics that target the dysregulated ECM proteins or help replace damaged tissue may improve clinical outcomes. [ABSTRACT FROM AUTHOR]

STUDY QUESTION Does palmitic acid (PA), the most common saturated free fatty acid (FFA) in individuals with obesity, contribute to anovulation through upregulation of the collagen-crosslinking enzyme lysyl oxidase (LOX) in the ovary? SUMMARY ANSWER Increased PA in individuals with obesity can cause LOX upregulation via the activation of hypoxia-inducible factor-1α (HIF-1α), resulting in abnormal collagen deposition in the ovary and anovulation, which can be ameliorated by metformin therapy. WHAT IS KNOWN ALREADY The underlying cause of anovulation in individuals with obesity is poorly defined, and accumulating evidence indicates that hormonal disturbance, insulin resistance, and inflammation may all play a role in the development of ovulation disorders in individuals with obesity. However, it remains to be determined whether PA plays a role in the regulation of LOX expression, thus disrupting ovarian extracellular matrix (ECM) remodelling in the ovary and resulting in impaired ovulation in individuals with obesity. STUDY DESIGN, SIZE, DURATION PA concentration and LOX protein abundance and activity in follicular fluid and ovarian tissue were compared between control (n = 21) subjects, patients with obesity with ovulation (n = 22), and patients with obesity with anovulation (n = 16). The effect of PA on LOX protein expression, and the underlying mechanism, was examined in primary human granulosa cells in vitro. The improvements in obesity conditions induced by LOX inhibition combined with metformin were investigated in a high-fat diet-induced obese rat model. PARTICIPANTS/MATERIALS, SETTING, METHODS The abundance of PA concentration and LOX activity was measured via a LOX activity assay and ELISA, respectively. The effect of PA on LOX protein expression was examined in the presence or absence of inhibitors of signalling molecules and siRNA-mediated knockdown of the putative transcription factor. Chromatin immunoprecipitation assays were subsequently conducted to further identify the responsible transcription factor. The role of metformin in the treatment of anovulation by LOX inhibition was investigated in a high-fat diet (HFD)-induced obese rat model. The numbers of retrieved total oocytes and metaphase II oocytes were recorded upon ovarian stimulation. Masson's trichrome staining was used to measure the total collagen content, and immunohistochemical staining and western blotting were used to measure LOX, HIF-1α, and collagen I and IV in the ovary. MAIN RESULTS AND THE ROLE OF CHANCE Significantly increased FFA, LOX, and collagen abundance were observed in the ovaries of obese women with anovulation, compared to healthy controls or obese women with ovulation. In a HFD-induced obese rat model, metformin corrected the distortion of ovarian morphology by decreasing LOX and collagen protein abundance in the ovary and improving oestrous cyclicity and ovulation. PA increased LOX expression via the activation of HIF-1α in human granulosa cells, which was attenuated by metformin. LARGE SCALE DATA N/A. LIMITATIONS, REASONS FOR CAUTION Several other saturated and polyunsaturated FFAs, such as stearic acid and arachidonic acid, are also increased in the blood of individuals with obesity, and increased levels of other FFAs may also contribute to the development of anovulation in individuals with obesity, which needs to be further verified in the future. WIDER IMPLICATIONS OF THE FINDINGS Elevated PA in individuals with obesity can cause LOX dysregulation via activation of HIF-1α, resulting in abnormal collagen deposition in the ovary and anovulation. This dysregulation can be ameliorated by metformin therapy through its local effect on ECM remodelling in the ovary, which is independent of its systemic effect on insulin sensitivity and chronic inflammation. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by the National Natural Science Foundation of China (grant numbers 82101730, 82130046, and 31900598) and Innovative Research Team of High-level local Universities in Shanghai (SHSMU-ZLCX20210201). All the authors declare no conflicts of interest in relation to this work. [ABSTRACT FROM AUTHOR]

Copper plays an important role in metabolic processes. Both deficiency and excess of this element have a negative effect and lead to pathological conditions. Copper is a cofactor of many enzymatic reactions. Its concentration depends on the delivery in the diet, the absorption in enterocytes, transport with the participation of ATP7A/ATP7B protein, and proper excretion. Copper homeostasis disorders lead to serious medical conditions such as Menkes disease (MD) and Wilson's disease (WD). A mutation in the ATP7A gene is the cause of Menkes disease, it prevents the supply of copper ions to enzymes dependent on them, such as dopamine β-hydroxylase and lysyl oxidase. This leads to progressive changes in the central nervous system and disorders of the connective tissue. In turn, Wilson's disease is an inherited autosomal recessive disease. It is caused by a mutation of the ATP7B gene encoding the ATP7B protein which means excess copper cannot be removed from the body, leading to the pathological accumulation of this element in the liver and brain. The clinical picture is dominated by the liver, neurological, and/or psychiatric symptoms. Early inclusion of zinc preparations and chelating drugs significantly improves the prognosis in this group of patients. The aim of the study is to analyse, based on the latest literature, the following factors: the etiopathogenesis, clinical picture, diagnostic tests, treatment, prognosis, and complications of disease entities associated with copper disturbances: Menkes disease and Wilson's disease. In addition, it is necessary for general practitioners, neurologists, and gastroenterologists to pay attention to these disease entities because they are recognized too late and too rarely, especially in the paediatric population. [ABSTRACT FROM AUTHOR]

Background: Pulmonary fibrosis features in damaged pulmonary structure or over-produced extracellular matrix and impaired lung function, leading to respiratory failure and eventually death. Fibrotic lungs are characterized by the secretion of pro-fibrotic factors, transformation of fibroblasts to myofibroblasts, and accumulation of matrix proteins. Hypothesis/purpose: Imperatorin shows anti-inflammatory effects on alveolar macrophages against acute lung injury. We attempt to evaluate the properties of imperatorin on the basis of fibroblasts. Methods: In in vitro, zymosan was introduced to provoke pro-fibrotic responses in NIH/3T3 or MRC-5 pulmonary fibroblasts. Imperatorin was given for examining its effects against fibrosis. The mice were stimulated by bleomycin, and imperatorin was administered to evaluate the prophylactic potential in vivo. Results: The upregulated expression of connective tissue growth factor (CTGF), a-smooth muscle actin (a-SMA), and collagen protein due to zymosan introduction was decreased by imperatorin in fibroblasts. Zymosan induced the activity of transglutaminase 2 (TGase2) and lysyl oxidase (LOX), which was also inhibited by the administration of imperatorin. Imperatorin alone enhanced sirtuin 1 (SIRT1) activity and growth differentiation factor 15 (GDF15) secretion in fibroblasts via LKB1/AMPK/CREB pathways. In addition, GDF15 exerted a beneficial effect by reducing the protein expression of CTGF, a-SMA, and collagen and the activities of TGase and LOX. Moreover, orally administered imperatorin showed prophylactic effects on bleomycin-induced pulmonary fibrosis in mice. Conclusion: Imperatorin reduces fibrotic marker expression in fibroblasts and also increases GDF15 secretion via the LKB1/AMPK/CREB pathway, attenuating profibrotic responses in vitro. Imperatorin also alleviates pulmonary fibrosis induced by bleomycin in vivo. [ABSTRACT FROM AUTHOR]