acyl-CoA Synthetase Long-chain Family Member Research Articles

Predictive value of early serum ACSL4 and ASITN/SIR grade for motor function recovery in patients with post-ischemic stroke lower limb neurological sequelae after modified constraint-induced movement therapy

BackgroundIschemic stroke accounts for over 85 % of all stroke types. Acyl-CoA synthetase long chain family member 4 (ACSL4) is considered to promote myocardial and cerebral ischaemia/ reperfusion. However, up to now, no study focused on the role of ACSL4 in patients with post-stroke lower limb neurological sequelae. ObjectiveThe present study aimed to investigate the predictive value of ACSL4 and collateral circulation for lower limb neurological sequelae of ischemic stroke patients after modified constraint-induced movement therapy (mCIMT). MethodsThis is a prospective cohort study which included 99 ischemic stroke patients with lower limb neurological sequelae who were admitted to our hospital during January 2021 to December 2022. All patients received mCIMT after the admission. Collateral circulation was evaluated by digital subtraction angiography (DSA) and graded by the American Society of Interventional and Therapeutic Neuroradiology/ Society of Interventional Radiology (ASITN/SIR) grading system. Enzyme linked immunosorbent assay (ELISA) was used to detect serum ACSL4. Basic characteristics were collected and lower limb motor function was measured by Fugl-Meyer score (FMS), modified Ashworth score (MAS) and Brunnstrom stage, as well as timed up and go (TUG) test, ten-Meter walk test (10MWT), and six-minute walk test (6MWT) before and after treatment. ResultsSerum ACSL4 and percentage of patients with ASITN/SIR 0–1 decreased significantly after treatment compared with the values before treatment. Patients with higher baseline serum ACSL4 values at admission showed significantly lower FMS scores, higher TUG and 10MWT, as well as lower 6MWT. Patients with ASITN/SIR grade 0–1 at admission only showed significantly higher TUG and 10MWT, as well as lower 6MWT. Receiver operating characteristic (ROC) curves showed ACSL4 and ASITN/SIR grade could be used to predict the prognosis. Logistic regression found only national institutes of health stroke scores (NIHSS) was the independent risk factor for post-treatment motor impairment after mCIMT. ConclusionHigher levels of ACSL4 and ASITN/SIR 0–1 are associated with poor recovery of motor functions of patients with post-stroke sequelae after mCIMT.

Protosappanin A Protects DOX-Induced Myocardial Injury and Cardiac Dysfunction by Targeting ACSL4/FTH1 Axis-Dependent Ferroptosis.

Doxorubicin (DOX) is an effective anticancer agent, but its clinical utility is constrained by dose-dependent cardiotoxicity, partly due to cardiomyocyte ferroptosis. However, the progress of developing cardioprotective medications to counteract ferroptosis has encountered obstacles. Protosappanin A (PrA), an anti-inflammatory compound derived from hematoxylin, shows potential against DOX-induced cardiomyopathy (DIC). Here, it is reported that PrA alleviates myocardial damage and dysfunction by reducing DOX-induced ferroptosis and maintaining mitochondrial homeostasis. Subsequently, the molecular target of PrA through proteome microarray, molecular docking, and dynamics simulation is identified. Mechanistically,PrA physically binds with ferroptosis-related proteins acyl-CoA synthetase long-chain family member 4 (ACSL4) and ferritin heavy chain 1 (FTH1), ultimately inhibiting ACSL4 phosphorylation and subsequent phospholipid peroxidation, while also preventing FTH1 autophagic degradation and subsequent release of ferrous ions (Fe2+) release. Given the critical role of ferroptosis in the pathogenesis of ischemia-reperfusion (IR) injury, this further investigation posits that PrA can confer a protective effect against IR-induced cardiac damage by inhibiting ferroptosis. Overall, a novel pharmacological inhibitor is unveiled that targets ferroptosis and uncover a dual-regulated mechanism for cardiomyocyte ferroptosis in DIC, highlighting additional therapeutic options for chemodrug-induced cardiotoxicity and ferroptosis-triggered disorders.

A highly selective inhibitor of discoidin domain receptor-1 (DDR1-IN-1) protects corneal epithelial cells from YAP/ACSL4-mediated ferroptosis in dry eye.

This study investigated the involvement of discoidin domain receptor (DDR) in dry eye and assessed the potential of specific DDR inhibitors as a therapeutic strategy for dry eye by exploring the underlying mechanism. Dry eye was induced in Wistar rats by applying 0.2% benzalkonium chloride (BAC), after which rats were treated topically for 7 days with DDR1-IN-1, a selective inhibitor of DDR1. Clinical manifestations of dry eye were assessed on Day-7 post-treatment. Histological evaluation of corneal damage was performed using haematoxylin and eosin (H&E) staining. In vitro, immortalized human corneal epithelial cells (HCECs) exposed to hyperosmotic stress (HS) were treated with varying doses of DDR1-IN-1 for 24 h. The levels of lipid peroxidation in dry eye corneas or HS-stimulated HCECs were assessed. Protein levels of DDR1/DDR2 and related pathways were detected by western blotting. The cellular distribution of acyl-CoA synthetase long chain family member 4 (ACSL4) and Yes-associated protein (YAP) was evaluated using immunohistochemistry or immunofluorescent staining. In dry eye corneas, only DDR1 expression was significantly up-regulated compared with normal controls. DDR1-IN-1 treatment significantly alleviated dry eye symptoms in vivo. The treatment remarkably reduced lipid hydroperoxide (LPO) levels and suppressed the expression of ferroptosis markers, particularly ACSL4. Overexpression or reactivation of YAP diminished the protective effects of DDR1-IN-1, indicating the involvement of the Hippo/YAP pathway in DDR1-targeted therapeutic effects. This study confirms the significance of DDR1 in dry eye and highlights the potential of selective DDR1 inhibitor(s) for dry eye treatment.

Proteomic and lipidomic analysis of the mechanism underlying astragaloside IV in mitigating ferroptosis through hypoxia-inducible factor 1α/heme oxygenase 1 pathway in renal tubular epithelial cells in diabetic kidney disease

Ethnopharmacological relevanceThe limitations of modern medicine in mitigating the pathological process of diabetic kidney disease (DKD) necessitate novel, precise, and effective prevention and treatment methods. Huangqi, the root of Astragalus membranaceus Fisch. ex Bunge has been used in traditional Chinese medicine for various kidney ailments. Astragaloside IV (AS-IV), the primary pharmacologically active compound in A. membranaceus, is involved in lipid metabolism regulation; however, its potential in ameliorating renal damage in DKD remains unexplored. Aim of the studyTo elucidate the specific mechanism by which AS-IV moderates DKD progression. Materials and methodsA murine model of DKD and high glucose-induced HK-2 cells were treated with AS-IV. Furthermore, multiomics analysis, molecular docking, and molecular dynamics simulations were performed to elucidate the mechanism of action of AS-IV in DKD, which was validated using molecular biological methods. ResultsAS-IV regulated glucose and lipid metabolism in DKD, thereby mitigating lipid deposition in the kidneys. Proteomic analysis identified 12 proteins associated with lipid metabolism regulated by AS-IV in the DKD renal tissue. Additionally, lipid metabolomic analysis revealed that AS-IV upregulated and downregulated 4 beneficial and 79 harmful lipid metabolites, respectively. Multiomics analysis further indicated a positive correlation between the top-ranked differential protein heme oxygenase (HMOX)1 and the levels of various harmful lipid metabolites and a negative correlation with the levels of beneficial lipid metabolites. Furthermore, enrichment of both ferroptosis and hypoxia-inducible factor (HIF)-1 signaling pathways during the AS-IV treatment of DKD was observed using proteomic analysis. Validation results showed that AS-IV effectively reduced ferroptosis in DKD-affected renal tubular epithelial cells by inhibiting HIF-1α/HMOX1 pathway activity, upregulating glutathione peroxidase-4 and ferritin heavy chain-1 expression, and downregulating acyl-CoA synthetase long-chain family member-4 and transferrin receptor-1 expression. Our findings demonstrate the potential of AS-IV in mitigating DKD pathology by downregulating the HIF-1α/HMOX1 signaling pathway, thereby averting ferroptosis in renal tubular epithelial cells. ConclusionsAS-IV is a promising treatment strategy for DKD via the inhibition of ferroptosis in renal tubular epithelial cells. The findings of this study may help facilitate the development of novel therapeutic strategies.

Hepatic Oxidative Stress and Cell Death Influenced by Dietary Lipid Levels in a Fresh Teleost.

Ferroptosis is a form of regulated cell death characterized by iron-dependent lipid peroxidation, affecting physiological and pathological processes. Fatty liver disease associated with metabolic dysfunction is a common pathological condition in aquaculture. However, the exact role and mechanism of ferroptosis in its pathogenesis and progression remains unclear. In this study, an experiment was conducted using different dietary lipid levels in the feeding of largemouth bass (Micropterus salmoides) for 11 weeks. The results revealed that the growth performance and whole-body protein content significantly increased with the elevation of dietary lipid levels up to 12%. The activities of antioxidant enzymes as well as the content of GSH (glutathione) in the liver initially increased but later declined as the lipid levels increased; the contents of MDA (malondialdehyde) and GSSG (oxidized glutathione) demonstrated an opposite trend. Moreover, elevating lipid levels in the diet significantly increased liver Fe2+ content, as well as the expressions of TF (Transferrin), TFR (Transferrin receptor), ACSL4 (acyl-CoA synthetase long-chain family member 4), LPCAT3 (lysophosphatidylcholine acyltransferase 3), and LOX12 (Lipoxygenase-12), while decreasing the expressions of GPX4 (glutathione peroxidase 4) and SLC7A11 (Solute carrier family 7 member 11). In conclusion, the optimal lipid level is 12.2%, determined by WG-based linear regression. Excess lipid-level diets can up-regulate the ACSL4/LPCAT3/LOX12 axis, induce hepatic oxidative stress and cell death through a ferroptotic-like program, and decrease growth performance.

Zinc finger translocation‑associated protein promotes ferroptosis through the upregulation of ACSL4 expression in vascular endothelial cells.

Numerous studies have reported the potential involvement of ferroptosis in the development of atherosclerosis (AS). Acyl-CoA synthetase long chain family member 4 (ACSL4) is an essential component in the promotion of ferroptosis. The present study aimed to investigate the role of ACSL4 and zinc finger translocation-associated protein (ZFTA) in the regulation of endothelial cell ferroptosis in AS. Human umbilical vein endothelial cells (HUVECs) with ACSL4 knockout were generated using CRISPR/Cas9 technology. To assess ferroptosis, malondialdehyde concentration, iron content and reactive oxygen species levels were quantified in the present study. In addition, western blot analysis was conducted to explore the potential mechanisms underlying ACSL4 and ZFTA in the modulation of ferroptosis in HUVECs. The results of the present study demonstrated that the expression levels of ACSL4 and ZFTA were significantly increased in human atherosclerotic plaques. In addition, ACSL4 knockout led to a reduced susceptibility to ferroptosis, while ZFTA contributed to ferroptosis in HUVECs. Results of the present study also demonstrated that ZFTA overexpression upregulated ACSL4 expression in HUVECs, whereas ZFTA knockdown led to decreased ACSL4 expression. Co-transfection experiments demonstrated that the ZTFA overexpression-mediated increase in ferroptosis was reversed following ACSL4 knockdown. Collectively, results of the present study highlighted that ACSL4 mediated the effects of ZFTA on the ferroptosis of HUVECs. Thus, the present study demonstrated the potential role of ACSL4 and ZFTA in the regulation of ferroptosis, and highlighted that ferroptosis-related pathways may act as potential targets in the treatment of AS.

A multifunctional nanoplatform for chemotherapy and nanocatalytic synergistic cancer therapy achieved by amplified lipid peroxidation

Traditional cancer chemotherapy suffers from low efficacy and severe side effects, limiting its use as a first-line treatment. To address this issue, we investigated a novel way to induce lipid peroxidation (LPO), which plays an essential role in ferroptosis and may be useful against cancer cells and tumors. In this study, a pH-responsive synergistic cancer therapy nanoplatform was prepared using CaCO3 co-loaded with oleanolic acid (OA) and lipoxygenase (LOX), resulting in the formation OLCaP NP. This nanoplatform exhibited good drug release properties in an acidic tumor environment owing to the presence of CaCO3. As a result of acidic stimulation at tumor sites, the OLCaP NP released OA and LOX. OA, a chemotherapeutic drug with anticancer activity, is already known to promote the apoptosis of cancer cells, and LOX is a natural enzyme that catalyzes the oxidation of polyunsaturated fatty acids, leading to the accumulation of lipid peroxides and promoting the apoptosis of cancer cells. More importantly, OA upregulated the expression of acyl-coenzyme A synthetase long-chain family member 4 (ACSL4), which promoted enzyme-mediated LPO. Based on our combined chemotherapy and nanocatalytic therapy, the OLCaP NP not only had remarkable antitumor ability but also upregulated ACSL4 expression, allowing further amplification of LPO to inhibit tumor growth. These findings demonstrate the potential of this nanoplatform to enhance the therapeutic efficacy against tumors by inducing oxidative stress and disrupting lipid metabolism, highlighting its clinical potential for improved cancer treatment. Statement of significanceThis study presents a novel nanoplatform that combines oleanolic acid (OA), a chemotherapeutic drug, and lipoxygenase (LOX), which oxidizes polyunsaturated fatty acids to trigger apoptosis, for targeted cancer therapy. Unlike traditional treatments, our nanoplatform exhibits pH-responsive drug release, specifically in acidic tumor environments. This innovation enhances the therapeutic effects of OA and LOX, upregulating acyl-CoA synthetase long-chain family member 4 expression and amplifying lipid peroxidation to promote tumor cell apoptosis. Our findings significantly advance the existing literature by demonstrating a synergistic approach that combines chemotherapy and nanocatalytic therapy. The scientific impact of this work lies in its potential to improve cancer treatment efficacy and specificity, offering a promising strategy for clinical applications and future research in cancer therapy.

DEX Inhibits H/R-induced Cardiomyocyte Ferroptosis by the miR-141-3p/lncRNA TUG1 Axis.

Ferroptosis is emerging as a critical pathway in ischemia/reperfusion (I/R) injury, contributing to compromised cardiac function and predisposing individuals to sepsis and myocardial failure. The study investigates the underlying mechanism of dexmedetomidine (DEX) in hypoxia/reoxygenation (H/R)-induced ferroptosis in cardiomyocytes, aiming to identify novel targets for myocardial I/R injury treatment. H9C2 cells were subjected to H/R and treated with varying concentrations of DEX. Additionally, H9C2 cells were transfected with miR-141-3p inhibitor followed by H/R treatment. Levels of miR-141-3p, long noncoding RNA (lncRNA) taurine upregulated 1 (TUG1), Fe2+, glutathione (GSH), and malondialdehyde were assessed. Reactive oxygen species (ROS) generation was measured via fluorescent labeling. Expression of ferroptosis-related proteins glutathione peroxidase 4 (GPX4) and acyl-CoA synthetase long-chain family member 4 (ACSL4) was determined using Western blot. The interaction between miR-141-3p and lncRNA TUG1 was evaluated through RNA pull-down assay and dual-luciferase reporter gene assays. The stability of lncRNA TUG1 was assessed using actinomycin D. DEX ameliorated H/R-induced cardiomyocyte injury and elevated miR-141-3p expression in cardiomyocytes. DEX treatment increased cell viability, Fe2+, and ROS levels while decreasing ACSL4 protein expression. Furthermore, DEX upregulated GSH and GPX4 protein levels. miR-141-3p targeted lncRNA TUG1, reducing its stability and overall expression. Inhibition of miR-141-3p or overexpression of lncRNA TUG1 partially reversed the inhibitory effect of DEX on H/R-induced ferroptosis in cardiomyocytes. DEX mitigated H/R-induced ferroptosis in cardiomyocytes by upregulating miR-141-3p expression and downregulating lncRNA TUG1 expression, unveiling a potential therapeutic strategy for myocardial I/R injury.

Unveiling the mechanism of photothermal therapy in acne man-agement: targeting sebaceous gland ferroptosis via umbilical cord mesenchymal stem cell membrane-encapsulated Au-Ag-PDA.

Branched gold and silver nanoparticles coated with polydopamine (Au-Ag-PDA) demonstrate high photothermal conversion efficiency. Utilizing umbilical cord mesenchymal stem cell membranes (MSCM) as an effective drug delivery system, our preliminary studies investigated the suppression of sebum secretion in sebaceous glands using MSCM-coated Au-Ag-PDA nano-particles (Au-Ag-PDA@MSCM) combined with 808nm laser irradiation, showing potential for dermatological applications in acne treatment. This study employs proteomic analysis, complemented by subsequent techniques such as Western blotting (WB), small interfering RNA (siRNA), and transmission electron microscopy, to further investigate the differential mechanisms by which Au-Ag-PDA and Au-Ag-PDA@MSCM-mediated photothermal therapy (PTT) suppress sebum secretion. Our proteomic analysis indicated mitochondrial respiratory chain damage in sebaceous gland tissues post-PTT, with further validation revealing ferroptosis in sebaceous cells and tissues. Acyl-CoA Synthetase Long-Chain Family Member 4 (Acsl4) has been identified as a critical target, with Au-Ag-PDA@MSCM demonstrating enhanced ferroptotic effects. These findings significantly advance our understanding of how PTT mediated by Au-Ag-PDA@MSCM nanoparticles reduces sebum secretion and underscore the pivotal role of MSCM in inducing ferroptosis in sebaceous glands, thus providing a robust theoretical foundation for employing PTT via specific molecular pathways in acne treatment.

Epigallocatechin gallate modulates ferroptosis through downregulation of tsRNA-13502 in non-small cell lung cancer

Ferroptosis, an iron-dependent regulated cell death mechanism, holds significant promise as a therapeutic strategy in oncology. In the current study, we explored the regulatory effects of epigallocatechin gallate (EGCG), a prominent polyphenol in green tea, on ferroptosis and its potential therapeutic implications for non-small cell lung cancer (NSCLC). Treatment of NSCLC cell lines with varying concentrations of EGCG resulted in a notable suppression of cell proliferation, as evidenced by a reduction in Ki67 immunofluorescence staining. Western blot analyses demonstrated that EGCG treatment led to a decrease in the expression of glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11) while increasing the levels of acyl-CoA synthetase long-chain family member 4 (ACSL4). These molecular changes were accompanied by an increase in intracellular iron, malondialdehyde (MDA), and reactive oxygen species (ROS), alongside ultrastructural alterations characteristic of ferroptosis. Through small RNA sequencing and RT-qPCR, transfer RNA-derived small RNA 13502 (tsRNA-13502) was identified as a significant target of EGCG action, with its expression being upregulated in NSCLC tissues compared to adjacent non-tumorous tissues. EGCG was found to modulate the ferroptosis pathway by downregulating tsRNA-13502 and altering the expression of key ferroptosis regulators (GPX4/SLC7A11 and ACSL4), thereby promoting the accumulation of iron, MDA, and ROS, and ultimately inducing ferroptosis in NSCLC cells. This study elucidates EGCG’s multifaceted mechanisms of action, underscoring the modulation of ferroptosis as a viable therapeutic approach for enhancing NSCLC treatment outcomes.

Effects of ferroptosis-related gene HSPB1 on acute myeloid leukemia.

The purpose of this study was to investigate the effects and potential mechanisms of ferroptosis-related gene heat shock protein beta-1 (HSPB1) on acute myeloid leukemia (AML). The RNA-seq and clinical data of AML samples were obtained from the Genomic Data Commons database, and the FerrDb database was used to screen the marker, drive and suppressor of ferroptosis. Besides, DESeq2 was applied for differential expression analysis on AML samples and screening for differentially expressed genes (DEGs). The screened DEGs were subjected to the intersection analysis with ferroptosis-related genes to identify the ferroptosis-related DEGs. Next, the functional pathways of ferroptosis-related DEGs were further be discussed by Gene Ontology as well as Kyoto Encyclopedia of Genes and Genomes enrichment analysis of DEGs. Additionally, lasso regression analysis was employed to determine the differential genes related to prognosis in patients with AML and the survival analysis was performed. Subsequently, quantitative real-time polymerase chain reaction and western blot assay were applied to detect the mRNA and protein expression levels of HSPB1 in normal/AML bone marrow tissues and human normal (HS-5)/AML (HL-60) bone marrow cells, respectively. Furthermore, HSPB1 was knocked down to assess the expression changes of glutathione peroxidase 4 and acyl-CoA synthetase long-chain family member 4. Ultimately, the viability and oxidative stress levels of HL-60 were analyzed by Cell Counting Kit-8 and biochemical detection. A total of 4986 DEGs were identified in AML samples, with 3324 up-regulated and 1662 down-regulated. The enrichment analysis illustrated that ferroptosis-related DEGs were significantly enriched in response to metal irons, oxidative stress, and other pathways. After lasso regression analysis, 17 feature genes related to the prognosis of patients with AML were obtained, with HSPB1 exhibiting a significant correlation. The reliability of our models was verified by Cox regression analysis and survival analysis of the hazard model. Furthermore, the outcomes of quantitative real-time polymerase chain reaction and western blot showed that mRNA and protein expression levels of HSPB1 were significantly increased in the AML Group and HL-60 cells. The knockdown of HSPB1 in HL-60 cells reduced the protein level of glutathione peroxidase 4, increased the protein level of acyl-CoA synthetase long-chain family member 4, decreased the cell viability, and aggravated oxidative stress. Ferroptosis-related gene HSPB1 is highly expressed in patients with AML. In addition, HSPB1 may be involved in the occurrence and development of AML by regulating oxidative stress and ferroptosis-related pathways. This study provides new clues for further understanding of AML molecular mechanisms. Also, HSPB1 is expected to be a potential therapeutic target for AML in the future.

Tetramethylpyrazine alleviates ferroptosis and promotes functional recovery in spinal cord injury by regulating GPX4/ACSL4

ObjectiveTetramethylpyrazine (TMP) has been demonstrated to alleviate neuronal ferroptosis following spinal cord injury (SCI), thereby promoting neural repair. However, the precise underlying mechanisms remain elusive. MethodsThe SCI model was established using a modified version of Allen's method. TMP (40, 80, 120, and 160 mg/kg) and ras-selective lethal 3 (RSL3) (5 mg/kg) were administered intraperitoneally once daily for 7 days. HE and Nissl staining were employed to examine histomorphology and neurons, respectively. Perls staining was used to identify the distribution of iron. A transmission electron microscope was used to observe the microcosmic morphology of mitochondria. Immunofluorescence staining and Western blot were used to analyze neuronal nuclear protein (NeuN) and glial fibrillary acidic protein (GFAP) surrounding injury sites. Additionally, glutathione peroxidase 4 (GPX4)/NeuN + cells and acyl-CoA synthetase long-chain family member 4 (ACSL4)/NeuN + cells were observed. RT-qPCR was conducted to examine the mRNA expression levels of GPX4 and ACSL4. ELISA were used to quantify the concentrations of GPX4, reactive oxygen species (ROS), L-glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), and tissue iron. ResultsTMP had an inhibitory effect on the concentrations of tissue iron, ROS, GSH, MDA, and SOD. TMP improved the microcosmic morphology of mitochondria and increased GPX4 level while decreasing that of ACSL4. TMP reduced lesion sizes, enhanced neuronal survival, and inhibited glial scar formation. However, the effect of TMP can be effectively reversed by RSL3. ConclusionTMP alleviates neuronal ferroptosis by regulating the GPX4/ACSL4 axis, thereby protecting the remaining neurons surrounding injury sites and reducing glial scar formation.

Interferon-α could induce liver steatosis to promote HBsAg loss by increasing triglyceride level

BackgroundThe correlation between metabolic syndrome (MetS) and hepatitis B surface antigen (HBsAg) loss remains to be further elucidated, particularly in patients receiving pegylated interferon-α (PEG-IFN) treatment. Methods758 patients with low HBsAg quantification who had received nucleos(t)ide analog (NUC) therapy for at least one year and subsequently switched to or add on PEG-IFN therapy over an unfixed course were enrolled. 412 patients were obtained with baseline data matched. A total of 206 patients achieved HBsAg loss (cured group) within 48 weeks. Demographic and biochemical data associated with MetS were gathered for analysis. HepG2.2.15 cell line was used in vitro experiments to validate the efficacy of interferon-α (IFN-α). ResultsThe proportion of patients with diabetes or hypertension in the uncured group was significantly higher than in the cured group. The levels of fasting blood glucose (FBG) and glycated albumin remained elevated in the uncured group over the 48 weeks. In contrast, the levels of blood lipids and uric acid remained higher in the cured group within 48 weeks. Triglycerides levels and liver steatosis of all patients increased after PEG-IFN therapy. Baseline elevated uric acid levels and hepatic steatosis may be beneficial for HBsAg loss. IFN-α could induce hepatic steatosis and indirectly promote HBsAg loss by increasing triglyceride level through upregulation of acyl-CoA synthetase long-chain family member 1(ACSL1). ConclusionsIFN-α could induce liver steatosis to promote HBsAg loss by increasing triglyceride level through upregulation of ACSL1. Comorbid diabetes may be detrimental to obtaining HBsAg loss with PEG-IFN therapy in CHB patients.

Propofol Mitigates Sepsis-Induced Brain Injury by Inhibiting Ferroptosis Via Activation of the Nrf2/HO-1axis.

Sepsis-associated encephalopathy (SAE) develops in 30-70% of hospitalized patients with sepsis. In intensive care units (ICUs), propofol is often administered to ensure an appropriate level of sedation in mechanically ventilated patients. Ferroptosis is a newly identified mode of cellular death characterized by the peroxidation of membrane lipids and excessive iron. This study was conducted to explore the interplay between propofol, sepsis, and ferroptosis. An acute systemic inflammatory model was constructed via the intraperitoneal administration of lipopolysaccharide (LPS). Nissl and Fluoro-Jade C (FJC) staining were employed to display neuronal damage and degeneration. Western blotting and immunofluorescence (IF) staining of Bax and Bcl-2 were used to confirm the neural apoptosis. QPCR of cytokines and DHE staining were used to indicate neuroinflammation. To validate ferroptosis, we assessed the content of malondialdehyde (MDA), GSH, and tissue iron, accompanied by transcription level of CHAC1, PTGS2 and GPX4. Additionally, we examined the content of acyl-CoA synthetase long-chain family member 4 (ACSL4), xCT (SLC7A11, solute carrier family 7 member 11), and glutathione peroxidase 4 (GPX4). The IF staining of Iba1-labeled microglia and GFAP-marked astrocytes were used to measure the gliosis. Erastin was pre-pretreated to confirm the anti-ferroptotic capability of propofol. ML385 was preconditioned to explore the role of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in propofol-repressed ferroptosis. Propofol dose-dependently inhibited the decrease of Nissl-positive neurons and the increase of FJC-stained neurons in septic hippocampus and cortex. Neural cytokines, oxidative stress, apoptosis and gliosis were reduced by propofol. Propofol repressed the level of MDA, iron, CHAC1, PTGS2, ACLS4 and restored the content of GSH, GPX4, xCT, Nrf2 and HO-1, thus inhibiting sepsis-induced ferroptosis. All protections from propofol could be reversed by eratsin and ML385 pretreatment. Propofol protected against sepsis-induced brain damage, neuroinflammation, neuronal apoptosis and gliosis through the activation of the Nrf2/HO-1 axis to combat ferroptosis.

Effect of dietary supplementation with sanguinarine on meat quality and lipid metabolism of broilers

Dietary Macleaya cordata extract (MCE) can improve the meat quality of poultry. However, the specific mechanism by which MCE regulates the meat quality has not been clarified yet. Sanguinarine (SAN) is one of the important natural active components in MCE. Our study aims to explore the regulatory mechanism of dietary SAN supplementation on meat quality through transcriptomic and gut microbiome analysis, thereby providing a basis for regularing meat quality with MCE. 240 1-day-old broilers were divided into 4 groups according to different doses of SAN (0, 0.225, 0.75, and 2.25 mg/kg). The results indicated that SAN significantly improve the physicochemical quality indicators of breast and thigh muscle in broilers, improved the serum biochemical indexes. Through transcriptome sequencing analysis of the liver and ileum tissues of broilers, we found that the differentially expressed genes induced by SAN were mainly enriched in lipid metabolism, which were related to the peroxisome proliferator-activated receptor (PPAR) pathway. It reconfirmed that SAN can regulate lipid metabolism in the body by promoting the expression of genes related to cholesterol metabolism, fatty acid transport and oxidation by RT-PCR, this ultimately affects the physicochemical quality of muscle. Additionally, through 16S rRNA sequencing analysis, we found that dietary addition of SAN increased the relative abundance of Bacteroides, Lactobacillus and unclassified_f_Lachnospiraceae, while decreased the relative abundance of Alistipes in ceca. To further investigate the impact of gut microbiota on lipid metabolism, we conducted a correlation analysis of PPAR pathway factor expression in cecum tissue and microflora structure. The results showed that Bacteroides exhibited a positive correlation with the expression of most genes in the PPAR signaling pathway. Unclassified_f__Lachnospiraceae is positively correlated with PPARγ, Cytochrome P450 family 7 subfamily A member 1 (CYP7A1) and Acyl-CoA synthetase long-chain family member 5 (ACSL5). In conclusion, dietary addition of SAN can promote the genes expression of the PPAR pathway, target the regulation of intestinal microflora structure and abundance and regulate lipid metabolism, thereby improving meat quality of broilers.

#1955 Ferroptotic proteins ACSL4 and ALOX15 as therapeutic targets in AKI

Abstract Background and Aims Ferroptosis is a regulated form of necrosis which is dependent on cellular iron and is characterized by the accumulation of lipid peroxides and failure of cellular antioxidant defences. We have previously described in vivo that ferroptosis is the primary cause of folic acid-induced acute kidney injury (FA-AKI) and that necroinflammation secondary to ferroptosis may further worsen kidney injury, since ferroptosis inhibition improved kidney function and decreased tubular cell death and oxidative stress. Acyl-CoA synthetase long-chain family member 4 (ACSL4) is involved in the incorporation of polyunsaturated fatty acid (PUFA) into membranes, while 15-Lipoxygenase (Alox15) catalyzes the regio- and enantioselective peroxidation of membrane-esterified PUFAs, forming the ultimate peroxidized species that induce ferroptosis. In the present work, we aim to explore the potential of both proteins as therapeutic targets in AKI, as well as the molecular characterization of kidney ferroptosis in cultured tubular cells. Method Animal model: Female 12- to 14-week-old C57BL/6J wild type mice received a single intraperitoneal (i.p) injection of folic acid or vehicle and were sacrificed 48 hours later. Troglitazone was intravenously administered for in vivo ACSL4 inhibition, and Compound 1 was i.p administered for in vivo ALOX15 inhibition. In vitro characterization of ferroptosis: HK2 human tubular kidney cells were incubated with arachidonic acid (AA) prior to sublethal RSL3 administration for sensitization to ferroptosis. We used Ferrostatin-1 (Fer-1) and Liproxstatin-1 (Lpx-1) as inhibitors of ferroptosis. The thiazolidinedione family members Rosiglitazone, Pioglitazone and Troglitazone were used as pharmacological inhibitors of ACSL4. We also performed transcriptional silencing of ACSL4 using a specific siRNA. Compound 1 and PD1646 were administered for in vitro Alox15 inhibition. Cellular lipid peroxidation was analyzed by flow cytometry with Bodipy 581/591 staining. To characterize the lipid signature of ferroptotic cells, supernatants were collected and 15-HETEs levels were measured by ELISA. Oxido-lipidomic analysis of ferroptotic cells was performed by LC-MS. Real Time PCR and Western Blot of whole kidneys and cultured cells were performed for the detection and quantification of ACSL4 and ALOX15. Cell death was assessed by measurement of cell viability (MTT assay) and cytotoxicity (LDH assay). Tissue cell death was assessed by TUNEL. Results Kidney transcriptomics identified Acsl4 as the most upregulated member of Acsl family during FA-AKI. This was validated at mRNA and protein levels. Supplementation with AA, the preferred ACSL4 substrate, sensitized HK2 tubular cells to ferroptosis under sublethal RSL3 conditions, and this was prevented with specific ferroptosis inhibitors Fer-1 and Lpx-1. Pharmacological inhibition of ACSL4 with Troglitazone and a specific siRNA protected from cell death and lipid peroxidation induced by co-stimulation of AA and RSL3 in HK2 cells. Likewise, ALOX15 proteins levels were also increased in FA-AKI at 48 hours. PD1646 and Compound 1, both used to inhibit ALOX15, protected from ferroptotic cell death and lipid peroxidation in HK2 cells. Lipidomic analysis on HK2 tubular cells stimulated with AA+RSL3 uncovered an increased content of key peroxidized lipid species involved in ferroptosis execution, which was alleviated by targeting ACSL4 or ALOX15. Additionally, renal function of FA-AKI in mice was improved by ACSL4 pharmacological inhibition with Troglitazone and with ALOX15 inhibition with Compound 1. Conclusion Our preliminary results suggest therapeutic potential of ACSL4 and ALOX15 as ferroptotic targes during AKI. High PUFA content sensitizes human tubular HK2 cells to cell death and lipid peroxidation in the presence of sublethal ferroptotic triggers, and this was prevented by targeting ACSL4 or ALOX15 both in vitro and in vivo in FA-AKI. Closely related lipid peroxide species were decreased by ACSL4 or ALOX15 inhibitors.

Soot nanoparticles promote ferroptosis in dopaminergic neurons via alteration of m6A RNA methylation in Parkinson’s disease

Soot nanoparticles (SNPs) are black carbon prevalent in atmospheric environment with significant impacts on public health, leading to neurodegenerative diseases including development of Parkinson’s disease (PD). This study investigated the effects of SNPs exposure on PD symptoms, employing both in vivo and in vitro PD models. In the in vivo experiments, animal behavior assessments showed that SNPs exposure exacerbated motor and cognitive impairments in PD mice. Molecular biology techniques further unveiled that SNPs aggravated degeneration of dopaminergic neurons. In vitro experiments revealed that SNPs exposure intensified ferroptosis of PD cells by increasing reactive oxygen species and iron ion levels, while reducing glutathione levels and mitochondrial membrane potential. Sequencing tests indicated elevated N6-methyladenosine (m6A) alteration of the ferroptosis-related protein, acyl-CoA synthetase long chain family member 4 (ACSL4). This study demonstrates that SNPs may exacerbate the onset and progression of PD by recruiting YTH domain-containing family protein 1 (YTHDF1) protein, enhancing m6A methylation in the ACSL4 5′UTR, amplifying ACSL4 protein expression, and accelerating the ferroptosis process in dopaminergic neurons. These molecular mechanisms underlying SNPs exacerbation of PD development may provide crucial insights for formulating environmental safety regulations and potential therapeutic strategies addressing PD in populations residing in regions with varied air quality.

Peroxynitrite-Triggered Carbon Monoxide Donor Improves Ischemic Stroke Outcome by Inhibiting Neuronal Apoptosis and Ferroptosis.

Cerebral ischemia-reperfusion injury produces excessive reactive oxygen and nitrogen species, including superoxide, nitric oxide, and peroxynitrite (ONOO-). We recently developed a new ONOO--triggered metal-free carbon monoxide donor (PCOD585), exhibiting a notable neuroprotective outcome on the rat middle cerebral artery occlusion model and rendering an exciting intervention opportunity toward ischemia-induced brain injuries. However, its therapeutic mechanism still needs to be addressed. In the pharmacological study, we found PCOD585 inhibited neuronal Bcl2/Bax/caspase-3 apoptosis pathway in the peri-infarcted area of stroke by scavenging ONOO-. ONOO- scavenging further led to decreased Acyl-CoA synthetase long-chain family member 4 and increased glutathione peroxidase 4, to minimize lipoperoxidation. Additionally, the carbon monoxide release upon the ONOO- reaction with PCOD585 further inhibited the neuronal Iron-dependent ferroptosis associated with ischemia-reperfusion. Such a synergistic neuroprotective mechanism of PCOD585 yields as potent a neuroprotective effect as Edaravone. Additionally, PCOD585 penetrates the blood-brain barrier and reduces the degradation of zonula occludens-1 by inhibiting matrix metalloproteinase-9, thereby protecting the integrity of the blood-brain barrier. Our study provides a new perspective for developing multi-functional compounds to treat ischemic stroke.

Oxidative Stress, Lipid Peroxidation and Ferroptosis Are Major Pathophysiological Signatures in the Placental Tissue of Women with Late-Onset Preeclampsia.

Preeclampsia, a serious and potentially life-threatening medical complication occurring during pregnancy, is characterized by hypertension and often accompanied by proteinuria and multiorgan dysfunction. It is classified into two subtypes based on the timing of diagnosis: early-onset (EO-PE) and late-onset preeclampsia (LO-PE). Despite being less severe and exhibiting distinct pathophysiological characteristics, LO-PE is more prevalent than EO-PE, although both conditions have a significant impact on placental health. Previous research indicates that different pathophysiological events within the placenta may contribute to the development of preeclampsia across multiple pathways. In our experimental study, we investigated markers of oxidative stress, ferroptosis, and lipid peroxidation pathways in placental tissue samples obtained from women with LO-PE (n = 68) compared to healthy control pregnant women (HC, n = 43). Through a comprehensive analysis, we observed an upregulation of specific molecules associated with these pathways, including NADPH oxidase 1 (NOX-1), NADPH oxidase 2 (NOX-2), transferrin receptor protein 1 (TFRC), arachidonate 5-lipoxygenase (ALOX-5), acyl-CoA synthetase long-chain family member 4 (ACSL-4), glutathione peroxidase 4 (GPX4) and malondialdehyde (MDA) in women with LO-PE. Furthermore, increased ferric tissue deposition (Fe3+) was observed in placenta samples stained with Perls' Prussian blue. The assessment involved gene and protein expression analyses conducted through RT-qPCR experiments and immunohistochemistry assays. Our findings underscore the heightened activation of inflammatory pathways in LO-PE compared to HC, highlighting the pathological mechanisms underlying this pregnancy disorder.

Enrichment of Bioactive Lipids in Urinary Extracellular Vesicles and Evidence of Apoptosis in Kidneys of Hypertensive Diabetic Cathepsin B Knockout Mice after Streptozotocin Treatment.

Cathepsin B (CtsB) is a ubiquitously expressed cysteine protease that plays important roles in health and disease. Urinary extracellular vesicles (uEVs) are released from cells associated with urinary organs. The antibiotic streptozotocin (STZ) is known to induce pancreatic islet beta cell destruction, diabetic nephropathy, and hypertension. We hypothesized that streptozotocin-induced diabetic kidney disease and hypertension result in the release of bioactive lipids from kidney cells that induce oxidative stress and renal cell death. Lipidomics was performed on uEVs isolated from CtsB knockout mice treated with or without STZ, and their kidneys were used to investigate changes in proteins associated with cell death. Lysophosphatidylethanolamine (LPE) (18:1), lysophosphatidylserine (LPS) (22:6), and lysophosphatidylglycerol (LPG) (22:5) were among the bioactive lipids enriched in uEVs from CtsB knockout mice treated with STZ compared to untreated CtsB mice (n = 3 uEV preparations per group). Anti-oxidant programming was activated in the kidneys of the CtsB knockout mice treated with STZ, as indicated by increased expression of glutathione peroxidase 4 (GPX4) and the cystine/glutamate antiporter SLC7A11 (XCT) (n = 4 mice per group), which was supported by a higher reactivity to 4-hydroxy-2-nonenal (4-HNE), a marker for oxidative stress (n = 3 mice per group). Apoptosis but not ferroptosis was the ongoing form of cell death in these kidneys as cleaved caspase-3 levels were significantly elevated in the STZ-treated CtsB knockout mice (n = 4 mice per group). There were no appreciable differences in the pro-ferroptosis enzyme acyl-CoA synthetase long-chain family member 4 (ACSL4) or the inflammatory marker CD93 in the kidneys (n = 3 mice per group), which further supports apoptosis as the prevalent mechanism of pathology. These data suggest that STZ treatment leads to oxidative stress, inducing apoptotic injury in the kidneys during the development of diabetic kidney disease and hypertension.