Explore the vast range of titles available.

Aims Acyl‐CoA synthetase long chain family member 4 (ACSL4) is closely related to tumor genesis and development in certain tissues. However, the function of ACSL4 in early brain injury (EBI) caused by subarachnoid hemorrhage (SAH) is unclear. In this study, we investigated the expression patterns and role of ACSL4 in SAH and post‐SAH EBI using a rat model of SAH. Methods The rat model of SAH was induced by autologous blood injection into the prechiasmatic cistern of rats. We also used two specific inhibitors of ferroptosis (Ferrostatin‐1 and Liproxstatin‐1) to investigate the role of ferroptosis in EBI. Results We found that ACSL4 levels in brain tissue increased significantly in post‐SAH EBI. Inhibiting the expression of ACSL4 using small interfering RNAs alleviated inflammation, blood‐brain barrier (BBB) impairment, oxidative stress, brain edema, and behavioral and cognitive deficits, and increased the number of surviving neurons, after SAH. Similar effects were obtained by suppressing ferroptosis. Conclusions ACSL4 exacerbated SAH‐induced EBI by mediating ferroptosis. These findings may provide a theoretical basis for potential therapy aimed at alleviating post‐SAH EBI. ACSL4 levels in brain tissue of rats increase significantly in EBI and brain damage after SAH could be reduced by down‐regulation of ACSL4. ACSL4 could trigger ferroptosis and aggravate brain damage via catalyzing lipid metabolism. It may provide a theoretical basis for potential therapy to alleviate EBI after SAH

Pancreatic cancer (PC) is a lethal malignant tumor of the digestive system with a low survival rate. Current therapies provide only modest benefits for patients and new therapeutic options are urgently needed. Schisandrin B (Sch B) has demonstrated novel antitumor activity in several preclinical models; however, its effects on PC remain unclear. In the present study, the anti-proliferative effects of Sch B in vitro were evaluated in PC cell lines. The underlying molecular mechanisms were explored using RNA sequencing, drug affinity responsive target stability (DARTS), molecular docking and small interfering RNA transfection. The antitumor effects of Sch B in vivo were evaluated using both a subcutaneous xenograft mouse model and an orthotopic genetically engineered mouse model. The in vitro studies showed that Sch B significantly inhibited the proliferation of PC cells and induced cell death in a dose-dependent manner. Mechanistically, transcriptome Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that differentially expressed genes were significantly enriched in the 'ferroptosis' signaling pathway. Sch B triggered ferroptosis by promoting iron overload, lipid peroxidation and glutathione (GSH) depletion, as well as regulating the expression of ferroptosis-related proteins [including GSH peroxidase 4, solute carrier family 3 member 2, acyl-CoA synthetase long-chain family member 4 (ACSL4), γ-glutamyl-cysteine ligase catalytic subunit and GSH synthetase]. Furthermore, pre-treatment with the ferroptosis inhibitor ferrostatin-1 partially reversed the anti-proliferative effects and ferroptosis-related events induced by Sch B. DARTS assays and molecular docking analyses confirmed the direct interaction between Sch B and ACSL4. Notably, silencing ACSL4 expression also partially reversed the anti-proliferative effects and ferroptosis-related events induced by Sch B. The in vivo studies demonstrated that Sch B suppressed tumor growth in subcutaneous xenograft models with good biosafety, and inhibited metastasis in orthotopic genetically engineered mice. In conclusion, Sch B may exert anti-proliferative effects at least partially by inducing ACSL4-dependent ferroptosis in PC.

Ferroptosis is a form of cell death characterized by a pro‐oxidative cellular milieu and iron‐dependent lipid peroxidation. Ferroptosis has been implicated in various forms of liver injury, in keeping with the major role of the liver in iron metabolism. Limited research has addressed potential differences in ferroptosis mediators with age and sex, especially in an in vivo model. The goal of this investigation was to evaluate hepatic labile iron and mediators of ferroptosis with ageing in both sexes. Because female animals generally display greater antioxidant defences than males, we hypothesized that females would display a phenotype resistant to ferroptosis. Here, we determined iron contents, protein expression of ferroptosis mediators and measures of oxidative injury in liver samples from 12‐ and 24‐month‐old male and female Fischer 344 rats. In comparison to males, the livers of female rats at both ages contained more non‐haem iron, which was associated with greater ferritin heavy chain expression and attenuated expression of transferrin receptor‐1. In female rats, the 24‐month‐old group had higher contents of thiobarbituric acid reactive substances compared with their 12‐month‐old counterparts, yet similar contents of labile iron. These results suggest a disconnect between labile iron contents and oxidative injury with age. Female animals also displayed greater expression of acyl‐CoA synthetase long‐chain family member 4 (ACSL4), a modulator of ferroptosis, and greater abundance of high molecular weight 4‐hydroxnonenal‐modified proteins. These results demonstrate clear differences in iron and ferroptosis mediators between sexes and suggest that female rats of this strain might be more susceptible to ferroptosis. What is the central question of this study? Do iron stores and ferroptosis mediators in the liver differ with age or sex? What is the main finding and its importance? We observed greater non‐haem iron, 4‐hydroxynonenal‐modified proteins and ACSL4 protein expression in female livers, suggesting greater susceptibility to ferroptosis.

The four major metabolic pathways in cells, including amino acid, glucose, nucleotide and lipid metabolism, constitute the fundamental framework of cellular metabolic networks. However, the intricate reciprocal regulatory mechanisms between amino acid metabolism and lipid metabolism remain poorly understood. In the present study, an essential amino acid-deficient culture medium was established and applied to cell cultures. Subsequent analysis using flow cytometry demonstrated that methionine deprivation significantly reduced cellular lipid accumulation and impaired the fatty acid uptake capacity. Mechanistic investigations using western blotting revealed that the methionine-methionine adenosyltransferase 2A (MAT2A)-S-adenosylmethionine (SAM) metabolic axis regulates the protein expression of ACSL4, a critical enzyme governing fatty acid uptake. Notably, the results indicated that the protein expression of MAT2A may be tightly regulated by SAM through a feedback mechanism, ensuring homeostasis of the methionine-MAT2A-SAM metabolic axis. In summary, the findings of the present study demonstrate that the methionine-MAT2A-SAM axis modulates lipid metabolism by regulating ACSL4 expression and function.

Baicalin is a natural flavonoid glycoside that confers protection against myocardial ischemia/reperfusion (I/R) injury. However, its mechanism has not been fully understood. This study focused on elucidating the role of ferroptosis in baicalin-generated protective effects on myocardial ischemia/reperfusion (I/R) injury by using the myocardial I/R rat model and oxygen–glucose deprivation/reoxygenation (OGD/R) H9c2 cells. Our results show that baicalin improved myocardial I/R challenge–induced ST segment elevation, coronary flow (CF), left ventricular systolic pressure , infarct area, and pathological changes and prevented OGD/R-triggered cell viability loss. In addition, enhanced lipid peroxidation and significant iron accumulation along with activated transferrin receptor protein 1 (TfR1) signal and nuclear receptor coactivator 4 (NCOA4)-medicated ferritinophagy were observed in in vivo and in vitro models, which were reversed by baicalin treatment. Furthermore, acyl-CoA synthetase long-chain family member 4 (ACSL4) overexpression compromised baicalin-generated protective effect in H9c2 cells. Taken together, our findings suggest that baicalin prevents against myocardial ischemia/reperfusion injury via suppressing ACSL4-controlled ferroptosis. This study provides a novel target for the prevention of myocardial ischemia/reperfusion injury.

Acyl-CoA synthetase long-chain family member 4 (ACSL4) is a member of the long chain family of acyl-CoA synthetase proteins, which have recently been shown to serve an important role in ferroptosis. Previous studies have suggested that ferroptosis is involved in the occurrence of glioma; however, the role of ACSL4 in glioma remains unknown. In the present study, a reduction of ferroptosis in human glioma tissues and glioma cells was observed. Subsequently, it was demonstrated that the expression of ACSL4 was also downregulated in human glioma tissues and cells. A ferroptosis inhibitor and inducer were used to investigate the effects of ferroptosis on viability. The results showed that promoting ferroptosis inhibited the proliferation of glioma cells, and that the use of inducers had the reverse effect. Therefore, it was hypothesized that the reduction in ACSL4 expression may have been involved in ferroptosis and proliferation in glioma. Overexpression of ACSL4 decreased expression of glutathione peroxidase 4 and increased the levels of ferroptotic markers, including 5-hydroxyeicosatetraenoic (HETE), 12-HETE and 15-HETE. Additionally, ACSL4 overexpression resulted in an increase in lactate dehydrogenase release and a reduction in cell viability. The opposite results were observed when ACSL4 was silenced. These findings suggest that ACSL4 regulates ferroptosis and proliferation of glioma cells. To further investigate the mechanism underlying ACSL4-mediated regulation of proliferation in glioma cells, cells were treated with small interfering (si)-ACSL4 and sorafenib, a ferroptosis inducer. sorafenib attenuated the ability of siRNA-mediated silencing of ACSL4, thus improving cell viability. These results demonstrate that ACSL4 protects glioma cells and exerts anti-proliferative effects by activating a ferroptosis pathway and highlight the pivotal role of ferroptosis regulation by ACSL4 in its protective effects on glioma. Therefore, ACSL4 may serve as a novel therapeutic target for the treatment of glioma.

Background Diabetic foot ulcers (DFU) is a serious complication of diabetes, and keratinocyte ferroptosis has been shown to accelerate its pathological progression. Chuanglin Ye (CLY), widely used in clinical practice for the treatment of DFU, has been reported to exert anti-inflammation effects and promote skin regeneration. However, its pharmacological mechanisms on DFU remain unclear. Methods The DFU rats were treated with CLY (0.225 and 0.45 g/mL) for 21 days to evaluate its therapeutic efficacy. The chemical composition of CLY was analyzed using UPLC-MS/MS. Network pharmacology, western blot, and immunohistochemical staining were performed to assess the anti-ferroptosis effects of CLY. To validate the protective role of CLY against ferroptosis, RSL3, a ferroptosis inducer, was applied in this study. Subsequently, HaCaT cells were exposed to advanced glycation end products (AGEs) to establish an in vitro model of keratinocyte ferroptosis, further confirming the inhibitory effects of CLY on ferroptosis. RNA sequencing was conducted to elucidate the molecular mechanisms underlying CLY-mediated protection against keratinocyte ferroptosis. The functional involvement of the ACSS2/ACSL4 axis was verified through plasmid-mediated gene overexpression in vitro. Molecular docking analysis was employed to identify potential bioactive compounds in CLY that target ACSS2. Results CLY administration significantly accelerated wound healing in DFU rats. Network pharmacology analysis indicated the regulation of ferroptosis underlies the therapeutic effect of CLY against DFU, which was further supported by its ability to ameliorate lipid peroxidation and iron overload. In contrast, the ferroptosis inducer RSL3 attenuated the protective effects of CLY in DFU rats. In vitro, CLY markedly suppressed AGEs-induced lipid peroxidation and excessive ROS level. Mechanistically, RNA-seq analysis and subsequent validation experiments revealed the anti-ferroptosis effect of CLY depends on the inhibition of ACSL4 acetylation in keratinocytes. Furthermore, ACSS2 was identified as a key protein promoting ACSL4 acetylation, which was inhibiting by CLY. Finally, six major compounds in CLY were identified as active constituents targeting ACSS2. Conclusion Our findings demonstrate CLY promotes DFU wound healing by inhibiting keratinocyte ferroptosis through suppressing ACSS2-mediated ACSL4 acetylation, highlighting its potential as a rational therapeutic approach for the management of DFU. Graphical Abstract

Immunoglobulin A nephropathy (IgAN), the most prevalent primary glomerular disease, is a major cause of end-stage renal disease. Ferroptosis, a novel cell death mode induced by iron-dependent phospholipid peroxidation, has been implicated in the progression of chronic kidney disease. Whereas, Acyl-CoA synthetase long-chain family member 4 (ACSL4) is a key enzyme in pro-ferroptotic lipid metabolism that plays a critical role in ferroptosis. In this study, the role of ACSL4-mediated ferroptosis in IgAN progression was investigated by identifying the cell subset ACSL4 + Loop of Henle cells (LOHs) in IgAN via single-cell RNA sequencing (scRNA-seq). LOH cell populations were screened by dimensionality reduction with Uniform Manifold Approximation and Projection (UMAP), and ACSL4 + LOHs were annotated using cell marker genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (GO/KEGG) pathway enrichment analyses were performed based on marker genes of ACSL4 + LOHs. Cell-cell communication networks were established to infer interactions between ACSL4 + LOHs and other cell types. Pathological changes and LOH proportions in IgAN and normal kidney tissues were observed by hematoxylin and eosin (H&E) and Masson staining. Expression levels of ACSL4 in LOHs were determined by immunofluorescence to further investigate its effect on cell function. The proportion of LOHs was significantly elevated in the IgAN group compared to the Control group, and ACSL4 expression was significantly upregulated in LOHs. ACSL4 + LOHs were highly expressed in the IgAN group and enriched in the Ferroptosis pathway. Cellular communication between ACSL4 + LOHs and ECs, MEs, and PTCs was significantly enhanced in interleukin-6 (IL6) ligand-receptor pairs (IL6R + IL6ST). The proportion of LOHs was elevated, and ACSL4 expression was significantly increased in LOHs in the IgAN group. High expression of ACSL4 + LOHs, as revealed by scRNA-seq analysis, may enhance ferroptosis in IgAN and trigger inflammatory responses, thereby contributing to disease progression. This study is expected to provide insights into the mechanisms underlying the progression of IgAN.

Ferroptosis contributes to ischemic injury in basic experiments, but the roles of ferroptosis in patients with acute ischemic stroke (AIS) who received reperfusion therapy were unclear. This study prospectively enrolled patients with AIS who underwent endovascular thrombectomy (EVT) and non-stroke controls between February 2019 and May 2023. The plasma levels of three ferroptosis biomarkers—heat shock protein 70 (HSP70), ferritin, and acyl-CoA synthetase long-chain family member 4 (ACSL4)—were measured at pre-EVT, immediately post-EVT, and 24 h post-EVT in stroke patients. Outcomes were assessed using modified Rankin Scale (mRS) score and mortality at 3 months. The study enrolled 150 stroke patients and 50 controls. Stroke patients had higher HSP70 levels than controls. Functional independence (mRS score 0–2) was achieved in 42.5% of 134 followed patients, which was inversely associated with ACSL4 level at 24 h (adjusted odds ratio [aOR] 0.12, 95% confidence interval [CI] 0.03–0.56, P  = 0.007) in multivariate logistic regression analyses. Morality occurred in 17.2% of these patients, which was inversely associated with pre-EVT HSP70 level (aOR 0.13, 95% CI 0.02–0.98, P  = 0.048). In conclusion, ferroptosis was involved in patients with AIS who underwent EVT, and the plasma levels of ACSL4 and HSP70 were significantly associated with clinical outcomes.

Acyl-CoA synthetase long-chain family member 4 (ACSL4) is an index of ferroptosis. Here, serum ACSL4 levels were examined to determine their prognostic significance and mediating roles in patients with acute intracerebral hemorrhage (ICH). In this observational analytical study, serum ACSL4 levels were measured at admission in 317 patients with supratentorial intraparenchymal hemorrhage and at study entry in 100 controls. The National Institutes of Health Stroke Scale (NIHSS) score and hematoma volume were used as the severity metrics. Poor prognosis was designated as modified Rankin Scale (mRS) 3-6 at six months following ICH. Stroke-associated pneumonia (SAP) was defined as an acute lower airway infection within a week post-ICH. The outcome variables of interest were SAP and poor prognosis. Multifactorial means were implemented for severity and outcome analyses. Patients had significantly higher serum ACSL4 levels than controls. Serum ACSL4 levels remained linearly connected with NIHSS scores, hematoma volume, SAP, mRS scores, and poor prognosis under restricted cubic spline and kept substantially associated with them even after adjusting for other confounding factors. The independent associations with poor prognosis and SAP were robust via sensitivity analysis, and exhibited no interactions with age, sex, tobacco smoking, and others through subgroup analysis. Regarding the predictive ability for poor prognosis and SAP under the receiver operating characteristic curve, serum ACSL4 levels were statistically comparable to the NIHSS scores and hematoma volume. Using mediation analysis, serum ACSL4 levels partially mediated the associations of NIHSS scores and hematoma volume with poor prognosis and SAP, and SAP in part mediated the relationship between serum ACSL4 levels and mRS scores plus poor prognosis. Enhanced serum ACSL4 levels post-ICH are significantly linked to ICH severity and clinical outcomes, and serum ACSL4 may partially interpret outcome associations, therefore extrapolating serum ACSL4 as a prognostic adjunct of ICH.