Hippocampal HDAC7 induces perioperative neurocognitive disorders via an NF-κB-MFN2-ACSL4 ferroptosis pathway.

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.

To investigate the diagnostic value of circulating ferroptosis-related markers in erectile dysfunction (ED) and identify independent risk factors for disease occurrence and severity. A total of 204 participants were enrolled, including 102 ED patients and 102 healthy controls. Clinical data and psychometric scores (IIEF-5, EHS, HAMD-17, HAMA-14, PSQI) were assessed. Serum glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), and acyl-CoA synthetase long-chain family member 4 (ACSL4) were quantified by ELISA. Group comparisons, correlation analyses, receiver operating characteristic (ROC) curves, and univariate and multivariate logistic regression were performed. Compared with controls, ED patients exhibited significantly lower GPX4 and SLC7A11 and higher ACSL4 levels, with greater changes in severe ED. GPX4 and SLC7A11 correlated positively with erectile function and negatively with depression, anxiety, and sleep disturbance, whereas ACSL4 showed opposite associations. ROC analyses demonstrated good diagnostic performance of GPX4 (AUC = 0.841), SLC7A11 (AUC = 0.867), and ACSL4 (AUC = 0.859), with excellent accuracy when combined (AUC = 0.958). Logistic regression identified GPX4 and SLC7A11 as protective factors and ACSL4 as a risk factor for ED. In severe ED, PSQI was an independent risk factor, whereas GPX4 and SLC7A11 were independent protective factors. Circulating ferroptosis-related markers, particularly in combination, provide strong diagnostic value for ED and reflect disease severity. GPX4, SLC7A11, and ACSL4 may serve as promising biomarkers and potential therapeutic targets for ED management.

Although multimodality treatment, including chemoradiotherapy and surgery has significantly improved the prognosis of patients with esophageal squamous cell carcinoma (ESCC), a valid predictor is crucial for individualized treatment. As acyl-CoA synthetase long-chain family member 4 (ACSL4) and glutathione peroxidase 4 (GPX4) are key genes with radiation responses and constituents of the ferroptosis signaling pathway, the present study adopted ACSL4 and GPX4 protein expression to explore their predictive and prognostic value in patients with ESCC receiving adjuvant radiotherapy. A total of 108 patients with thoracic ESCC who had undergone radical surgery and adjuvant radiotherapy were enrolled in the present retrospectively study. ACSL4 and GPX4 immunohistochemistry experiments were performed on paraffin-embedded tumor samples. The prognostic value of ACSL4 and GPX4 was examined using survival analysis, and the predictive value of ACSL4 and GPX4 for long-term survival was examined using univariate and multivariate Cox regression analyses, and verified by receiver operating characteristic (ROC) analysis. The survival analysis revealed that overall survival (OS) and disease-free survival (DFS) were significantly longer in the high ACSL4 expression group, and the DFS was significantly shorter in the high GPX4 expression group. The results of univariate and multivariate Cox regression analyses revealed that the ACSL4 expression level was an independent predictor for OS and DFS, and that the GPX4 expression level was an independent predictor for DFS. ROC analysis verified the predictive role of ACSL4 expression for DFS and OS, with an area under the curve (AUC) of 0.713 and 0.663. The present study demonstrates that ACSL4 and GPX4 may serve as valuable prognostic biomarkers for long-term survival, and play a key translational role in individualized therapy for patients with ESCC.

Sulforaphane, an NRF2 agonist, alleviates ferroptosis in acute liver failure by regulating HDAC6 activity

ObjectiveTo explore the correlations between diabetic nephropathy (DN) and serum levels of glutathione peroxidase 4 (GPX4), acyl-CoA synthetase long-chain family member 4 (ACSL4), iron, transferrin (Tf), and ferritin in patients with type 2 diabetes mellitus (T2DM).MethodsAccording to the urinary albumin excretion rate(UAER) or estimated glomerular filtration rate (eGFR) levels, a total of 123 patients with T2DM were separately divided into normoalbuminuria (NO), microalbuminuria (MI), macroalbuminuria (MA) groups, and G1 (eGFR ≥ 90 mL/min), G2 (eGFR ≤ 60 mL/min to < 90 mL/min), and G3 groups (eGFR< 60 mL/min), with 33 healthy participants as the control (HC). The differences in serum GPX4, ACSL4, iron, Tf, and ferritin levels between groups were compared, and the relationships between these levels were analysed. The independent correlations between UAER or DN severity and serum GPX4, ACSL4, iron, Tf, and ferritin levels were analysed by multiple linear and multinomial logistic regression, respectively.ResultsTo the patients with T2DM, with the increase in UAER levels, GPX4, iron, and Tf levels gradually decreased, whereas ACSL4 levels increased, meanwhile with the decrease in eGFR levels, GPX4 and Tf levels gradually decreased, whereas ACSL4 levels increased. UAER were independently and positively correlated with ACSL4 [β = 17.53, 95% confidence interval (CI; 11.94, 23.13)] and negatively correlated with GPX4 [β = −1.633, 95% CI (−2.77, -0.496)] and Tf [β = −52.94, 95% CI (-95.78, −10.11)].The NO and MI groups were considered as reference groups, respectively. The severity of DN was negatively correlated with serum GPX4 [odds ratio (OR) = 0.925 and 0.902, p =0.015 and 0.001], and Tf (OR = 0.109 and 0.119, p =0.043 and 0.034), and positively correlated with ACSL4 (OR = 1.952 and 1.865, both p <0.001) in the MA group.ConclusionDN severity was negatively correlated with serum GPX4 and Tf levels and positively correlated with serum ACSL4 levels in patients with T2DM.

ObjectiveEpithelial ovarian cancer (EOC) is the most common and lethal type of ovarian cancer, and the cross-talk between tumor cell ferroptosis and macrophages is essential to cancer progression. This study aims to investigate the roles of ubiquitin-specific protease 7 (USP7) and acyl-CoA synthetase long-chain family member 4 (ACSL4) in the pathogenesis of EOC.Material and MethodsThe expression patterns of USP7 and ACSL4 in EOC cell lines were first determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot. ACSL4 recombinant protein was applied alone or in conjunction with a USP7 overexpression plasmid in EOC cells, and the effects of USP7 and ACSL4 on EOC cell proliferation and apoptosis were assessed using colony formation assays and terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling staining. The effects of USP7 and ACSL4 on ferroptosis in EOC cells were evaluated by measuring reactive oxygen species (ROS) fluorescence intensity, malondialdehyde (MDA), glutathione (GSH) levels, and glutathione peroxidase 4 (GPX4) messenger RNA (mRNA) levels. Co-culture of EOC cell-conditioned medium treated with ACSL4 recombinant protein or USP7 overexpression plasmid was performed with Human Acute Monocytic Leukemia Cell Line (THP-1) macrophages, and the expression levels of cluster of differentiation 86 and cluster of differentiation 206 were analyzed by flow cytometry. The expression levels of M1 polarization markers and M2 markers in macrophages were measured by qRT-PCR.ResultsACSL4 was expressed at low levels in the EOC cell lines, whereas USP7 was expressed at high levels. Treatment with ACSL4 recombinant protein reduced colony formation and increased apoptotic cell levels in the EOC cells (P < 0.001). In addition, ACSL4 treatment increased ROS fluorescence intensity and MDA levels while decreasing GSH levels and GPX4 expression (P < 0.001). Furthermore, ACSL4 treatment promoted the polarization of THP-1 macrophages toward M1, increasing the expression of M1 markers (P < 0.001). USP7 overexpression exerted the opposite effect (P < 0.001).ConclusionThis study reveals the critical role of USP7 in the progression of EOC. ACSL4 inhibits EOC growth and anti-apoptosis by inhibiting USP7-induced antiferroptosis and anti-M1 macrophage polarization, highlighting this mechanism as a potential therapeutic target in EOC.

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.

Sevoflurane induces neurotoxicity and cognitive impairment, with long noncoding RNAs (lncRNAs) playing key roles in nervous system diseases. This study explored lncRNA H19's function in sevoflurane-induced neurotoxicity. SH-SY5Y cell viability and apoptosis were assessed via CCK8 and TUNEL assays. Gene expression was measured by RT-qPCR, while reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH), and iron levels were quantified. Subcellular fractionation determined H19 localization, and luciferase assays confirmed H19/miR-20a-5p and miR-20a-5p/Acyl-CoA synthetase long chain family member 4 (ACSL4) interactions. Western blot analyzed ACSL4, apoptosis-, and ferroptosis-related proteins. The results showed that sevoflurane reduced viability, promoted apoptosis and ferroptosis, and upregulated H19 and ACSL4. H19 knockdown mitigated neurotoxicity by restoring viability, GSH, solute carrier family 7 member 11 (SLC7A11), and glutathione peroxidase 4 (GPX4), while reducing apoptosis, MDA, ROS, and iron. Mechanistically, H19 sponged miR-20a-5p to elevate ACSL4. Rescue assays showed miR-20a-5p inhibition or ACSL4 overexpression reversed H19 silencing's protective effects. Thus, H19 depletion alleviates sevoflurane-induced neuronal damage via the miR-20a-5p/ACSL4 axis, suggesting a potential therapeutic target.

(1) Background: Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant, and it is receiving increasing attention regarding its human health risks due to its extensive use. Endothelial dysfunction is a mark of cardiovascular disease, but the basic mechanism of PFOS-induced endothelial dysfunction is still not fully understood. Ferroptosis is a newly defined regulatory cell death driven by cellular metabolism and iron-dependent lipid peroxidation. Although ferroptosis has been shown to be involved in the pathogenesis of cardiovascular diseases, the involvement of ferroptosis in the pathogenesis of endothelial dysfunction caused by PFOS remains unclear. (2) Purpose: To explore the role of ferroptosis in the dysfunction of endothelial cells and underlying mechanisms. (3) Methods: Human umbilical vein endothelial cells (HUVECs) were exposed to PFOS or PFOS and Fer-1. The viability, morphology change under electronic microscope, lipid-reactive oxygen species (lipid-ROS), and production of nitric oxide (NO) were determined. The expression of glutathione peroxidase 4(GPX4), ferritin heavy chain protein 1 (FTH1), heme oxygenase 1 (HO-1) and Acyl-CoA synthetase long-chain family member 4 (ACSL4) were analyzed via Western blot analysis. (4) Results: PFOS was shown to cause a decrease in viability and morphological changes of mitochondria, and well as an increase in lipid droplets. The expression of GPX4, FTH1 and HO-1 was decreased, and that of ACSL4 was increased after exposure to PFOS. In addition to the above-mentioned ferroptosis-related manifestations, there was also a reduction in NO content. (5) Conclusions: PFOS induces ferroptosis by regulating the GPX4 and ACSL4 pathways, which leads to HUVEC dysfunction.

Cancer-associated fibroblasts (CAFs) participate in the development of the tumor microenvironment through the secretion of exosomes. Acyl-CoA synthetase long-chain family member 4 (ACSL4) is an essential component of ferroptosis. However, the regulatory mechanism of ACSL4 in breast cancer remains unexplored. The study aimed to determine the influence of exosomal miR-454-3p from CAFs on lipid metabolism and ferroptosis. CAF-derived exosomes (CAF-exo) were isolated from breast cancer tissue of breast cancer patients and characterized using transmission electron microscopy (TEM) and Western blot. Luciferase reporter assay and RNA immunoprecipitation (RIP) were used to demonstrate the relationship between miR-454-3p and ACSL4. Cell viability and ferroptosis-related markers were detected by CCK-8 and Western blot. Malondialdehyde (MDA), glutathione (GSH), and iron levels were detected. Reverse transcription-quantitative PCR (RT-qPCR) and fluorescence in situ hybridization (FISH) were used to assess miR-454-3p expression. miR-454-3p and ACSL4 levels were abnormally expressed in breast cancer tissues. CAF-exo significantly enhanced cell viability and GSH levels and suppressed MDA, and iron levels. CAF-exo upregulated ferroptosis suppressor protein 1 (FSP1) and glutathione peroxidase 4 (GPX4) expression, and reduced ACSL4 levels. miR-454-3p was strongly expressed in CAF-exo, and exosomal miR-454-3p suppressed lipid metabolism and ferroptosis in breast cancer cells. The effects of miR-454-3p inhibitor on lipid metabolism and ferroptosis were eliminated by ACSL4 knockdown. CAF-secreted exosomal miR-454-3p inhibited lipid metabolism and ferroptosis by targeting ACSL4 in breast cancer. This study revealed a novel molecular mechanism that offers a potential therapeutic intervention in breast cancer treatment.

Endothelial dysfunction caused by low androgen levels in penile tissue can lead to erectile dysfunction. The exact mechanism of endothelial dysfunction has not been thoroughly studied. The study sought to verify whether low androgen levels induce ferroptosis of endothelial cells in rat penile tissue. Rat penile cavernous endothelial cells (CP-R133) were divided into a no-androgen group (Dihydrotestosterone (DHT): 0nmol/L), very low-androgen group (DHT: 0.1nmol/L), low-androgen group (DHT: 1nmol/L), DHT = 10nmol/L group, DHT (0nmol/L) + ferrostatin-1 (Fer-1) group, DHT (0.1nmol/L) + Fer-1 group, DHT (1nmol/L) + Fer-1 group, DHT (10nmol/L) + Fer-1 group. Cell viability, intracellular ferrous ion (Fe2+), malondialdehyde (MDA), GSH into oxidized glutathione (GSSG), reactive oxygen species (ROS), nitric oxide (NO), transferrin receptor 1 protein (TfR1), solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), acyl-CoA synthetase long-chain family member 4 (ACSL4), endothelial nitric oxide synthase (eNOS), and phospho-eNOS (p-eNOS) were detected. Low androgen levels could induce ferroptosis of rat penile cavernous endothelial cells in vivo by upregulating the expressions of TfR1 and ACSL4 and downregulating the expressions of SLC7A11 and GPX4. Cell viability, the levels of glutathione (GSH), NO, SLC7A11, GPX4, and p-eNOS/eNOS in the DHT = 0nmol/L group were lower than those in the other groups (P < .05). The levels of Fe2+, ROS, MDA, GSSG, TfR1, and ACSL4 in the DHT = 0nmol/L group were higher than those in the other groups (P < .05). Cell viability and the levels of GSH, NO, SLC7A11, GPX4, and p-eNOS/eNOS in the DHT = 1nmol/L group were lower than those in the DHT (1nmol/L) + Fer-1 group, DHT = 10nmol/L group, and DHT (10nmol/L) + Fer-1 group (P < .05). The levels of Fe2+, ROS, MDA, GSSG, TfR1, and ACSL4 in the DHT = 1nmol/L group were higher than those in the DHT (1nmol/L) + Fer-1 group, DHT = 10nmol/L group, and DHT (10nmol/L) + Fer-1 group (P < .05). A ferroptosis inhibitor might be a novel drug for treating erectile dysfunction caused by low androgen level. The results of this study need to be further confirmed in in vitro and in human studies. Meanwhile, further investigation is needed to clarify whether low androgen levels affect ferroptosis of rat penile cavernous smooth muscle and nerve cells. Low androgen levels can induce ferroptosis of endothelial cells in rat penile tissue. Inhibition of ferroptosis can reverse endothelial dysfunction caused by low androgen levels.

Epilepsy is a chronic brain disorder with unclear pathogenesis and no effective biomarkers. This study aims to identify potential biomarkers and elucidate the regulatory pathways in epilepsy. Epilepsy-associated differentially expressed genes (DEGs) were discovered from the GSE60772, GSE88992, and GSE100202 datasets. Hub genes were determined from a protein-protein interaction (PPI) network, followed by screening of downstream pathways of growth arrest and DNA damage inducible beta (GADD45B). GADD45B was silenced in lithium-pilocarpine-induced epileptic rats and glutamate-treated HT22 cells to investigate its effects on hippocampal neuron injury, ferroptosis, mitochondrial homeostasis, and its downstream signaling pathway. GADD45B as an epilepsy-associated hub gene was highly expressed in the hippocampal tissues of epileptic rats. Silencing GADD45B in epileptic rats suppressed neuronal injury and death. It also decreased Fe2+, malondialdehyde (MDA), 4-hydroxy-2-nonenal (4-HNE), reactive oxygen species (ROS), and hypoxia-inducible factor-1α (HIF-1α) but increased glutathione (GSH) in epileptic rats and HT22 cells, as well as suppressed acyl-CoA synthetase long chain family member 4 (ACSL4) expression and increased glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11) expression. Mitochondrial homeostasis was maintained after silencing GADD45B via suppressing mitofusin 1 (MFN1) and mitofilin. The HIF-1 signaling pathway was a downstream pathway of GADD45B, and its activation reversed the protective effects of GADD45B silencing on glutamate-induced neuronal death, ferroptosis, and mitochondrial homeostasis. Silencing GADD45B attenuates epileptic neuronal death by inhibiting ferroptosis and maintaining mitochondrial homeostasis via inhibiting the HIF-1 signaling pathway, which provides novel insights into epilepsy pathogenesis and potential biomarkers.

Objective: To analyze the effect and mechanisms of tigecycline on the proliferation of liver cancer cells in mouse model. Methods: Human hepatocellular carcinoma G2 (HepG2), human hepatocellular carcinoma 7 (Huh7), human hepatocellular carcinoma 3B (Hep3B) and Mahler's human hepatocellular carcinoma 97 high metastatic (MHCC97H) were divided into 6 groups respectively: group T0 (without tigecycline), group T1 (1.25 μmol/L tigecycline), group T2 (2.50 μmol/L tigecycline), group T3 (5.00 μmol/L tigecycline), group T4 (10.00 μmol/L tigecycline), and group T5 (20.00 μmol/L tigecycline). The proliferation capabilities of each group were compared after 48 hours of treatment (cell survival rate, the experiment was repeated 3 times). Based on the results of the effect of tigecycline on the proliferation ability of liver tumor cells, the mRNA and protein levels of ferroptosis-related genes [Acyl-CoA synthetase long chain family member 4 (ACSL4), glutathione peroxidase 4 (GPX4), and solute vector family member 11 (SLC7A11) ] in HepG2 and Hep3B cells in groups T0, T2 and T3 were detected (the experiment was repeated 3 times). Based on the results of the effects of tigecycline on the genes and protein levels of ACSL4, GPX4, and SLC7A11 in HepG2 and Hep3B, HepG2 and Hep3B cells were divided into 4 groups respectively: group T0, group T3, group T3F [5.00 μmol/L tigecycline combined with 10.00 μmol/L Ferrostatin-1 (Fer-1)] and group T3P [5.00 μmol/L tigecycline combined with 10.00 μmol/L ACSL4 specific inhibitor (PRGL493)], to compare the ACSL4 protein levels and cell proliferation abilities among different groups (cell survival rate, the experiment was repeated 3 times). HepG2 or Hep3B cell suspensions were subcutaneously injected into BALB/c nude mice to construct the subcutaneous tumor-bearing model of liver tumors in nude mice. On the 6th day, the mice were randomly divided into 3 groups (5 mice in each group for the HepG2 and Hep3B cell liver tumor nude mouse models): group N (no treatment), group TIG (treated with 100 mg/kg tigecycline), and group TP (treated with 100 mg/kg tigecycline combined with 0.5 mg/kg PRGL493). The effects of tigecycline on the proliferation of liver tumor cells in vivo and the ACSL4 protein in tumor tissues were detected, and the mechanism by which tigecycline inhibits the proliferation of liver tumor cells was analyzed. Results: The survival rates of HepG2, Huh7, Hep3B, and MHCC97H cells in T1, T2, T3, T4, and T5 groups were all lower than that of T0 group (all P<0.05); in both HepG2 and Hep3B cells, there was no statistically significant difference in the mRNA levels of ACSL4, GPX4, and SLC7A11, or in the protein levels of GPX4 and SLC7A11 between the T3 and T0 groups (all P>0.05). However, the ACSL4 protein levels of HepG2 and Hep3B cells in T3 group were all higher than that of T0 group (all P<0.05). The ACSL4 protein levels of HepG2 and Hep3B cells in T3F and T3P groups were lower than that of T3 group (all P<0.05), and the cell survival rates of HepG2 and Hep3B cells in T3F and T3P groups were higher than that of T3 group(all P<0.05). The tumor volumes of nude mouse subcutaneous tumor models in TIG group on the 21st day were lower than that of N group(all P<0.05). The tumor volumes of nude mouse subcutaneous tumor models in TP group were higher than that of TIG group (all P<0.05). Conclusions: Tigecycline inhibits the proliferation of liver cancer cells, and its mechanism may be related to promoting ACSL4-mediated ferroptosis.

Aims: Although there is evidence that patients with stroke who exercise regularly before stroke have a better prognosis than those who do not exercise, the detailed mechanism remains unclear. Moreover, neuronal death plays a central role in neurological dysfunction caused by ischemic stroke. Thus, we investigated whether exercise could reduce stroke-induced neuronal death and its associated mediators in the current study. Results: Ferroptosis was the most dominant form of programmed cell death in neurons. Preconditioning exercise before stroke improved the neurological function and decreased the infarct area in rats with ischemic stroke. Preconditioning exercise attenuated stroke-induced ferroptosis by reducing lipid peroxidation (LPO) production, upregulating glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11), and downregulating acyl-CoA synthetase long-chain family member 4 (ACSL4). High-throughput sequencing and dual luciferase reporter assays revealed that exercise-induced exosomal miR-484 inhibits Acsl4 expression. Moreover, we showed that exercise-induced exosomal miR-484 is mainly derived from skeletal muscle, and the neuroprotective effect of preconditioning exercise is suppressed by inhibiting miR-484 production in skeletal muscle. Innovation: This study suggested that neuronal ferroptosis is the most dominant form of programmed cell death in a hypoxic environment. Moreover, we showed that the ferroptosis pathway is a potential therapeutic target in ischemic stroke and that preconditioning exercise could be an effective antioxidant intervention for cerebral ischemia. Conclusion: Our work revealed that preconditioning exercise before stroke exerts neuroprotective effects against brain ischemia by skeletal muscle-derived exosomal miR-484 via inhibiting ferroptosis. Antioxid. Redox Signal. 41, 769-792.

Glioblastoma (GBM) is classified as a stage-IV glioma. Unfortunately, there are currently no curative treatments for GBM. Poly(rC)-binding protein 1 (PCBP1) is a cytosolic iron chaperone with diverse functions. PCBP1 is also known to regulate autophagy, but the role of PCBP1 in ferroptosis, iron-dependent cell death pathway, remains unrevealed in GBM cells. Here, we investigated the effects of borax, a boron compound, on the ferroptosis signaling pathway mediated by PCBP1 and autophagy. The study analyzed cell viability, proliferation, and cell cycle on U87-MG and HMC3 cells to investigate the effects of borax. After determining the cytotoxic concentrations of borax, morphological analyzes and measurement of PCBP1, Beclin1, malondialdehyde (MDA), glutathione (GSH), glutathione peroxidase 4 (GPx4) and acyl-CoA synthetase long chain family member 4 (ACSL4) levels were performed. Finally, expression levels of PCBP1, Beclin1, GPx4 and ACSL4, and caspase-3/7 activity were determined. We found that borax reduced U87-MG cell viability in a concentration- and time-dependent manner. Additionally, borax altered cell proliferation and remarkably reduced S phase in the U87-MG cells and exhibited selectivity by having an opposite effect on normal cells (HMC3). According to DAPI staining, borax caused nuclear deficits in U87-MG cells. The result showed that borax in U87-MG cells induced reduction of the PCBP1, GSH, and GPx4 and enhancement of Beclin1, MDA, and ACSL4. Furthermore, borax triggered apoptosis by activating caspase 3/7 in U87-MG cells. Our study indicated that the borax has potential as an anticancer treatment for GBM via regulating PCBP1/Beclin1/GPx4/ACSL4 signaling pathways.