Mechanistic study of electroacupuncture preconditioning in alleviating myocardial ischemia-reperfusion injury in rats: involvement of mTOR/ROS signaling pathway to inhibit ferroptosis.

PURPOSE: The objective of this study was to investigate the mechanism of electroacupuncture pretreatment in reducing myocardial ischemia-reperfusion injury in rats. MATERIALS AND METHODS: The comparison of HR among the different groups did not yield statistically significant differences (p > 0.05). Additionally, the trend of HR change at different time points within each group was not statistically significant (p > 0.05). In contrast, the comparison of SBP among the different groups showed statistically significant differences (p < 0.05). Furthermore, the trend of SBP change at different time points within each group exhibited significant differences (p < 0.05). RESULTS: Compared to the Sham group, rats in the I/R group and EA control group showed a significant decrease in EF, FS, SOD, p-mTOR/mTOR, GPX4, and FTH1, and an increase in CK-MB, cTnI, LDH, iron, ROS, MDA, ACSL4, and NCOA4 (p < 0.05). Compared to EA control group, rats in the EA group exhibited a significant increase in EF, FS, SOD, p-mTOR/mTOR, GPX4, and FTH1, and a decrease in CK-MB, cTnI, LDH, iron, ROS, MDA, ACSL4, and NCOA4 (p < 0.05). Compared to the EA group, rats in the EA + RAP group showed a significant decrease in EF, FS, SOD, p-mTOR/mTOR, GPX4, and FTH1, and an increase in CK-MB, cTnI, LDH, iron, ROS, MDA, ACSL4, and NCOA4 (p < 0.05). CONCLUSIONS: Electroacupuncture preconditioning confers protective effects against myocardial ischemia-reperfusion injury in rats. Its mechanism may involve the activation of the mTOR/ROS signaling pathway by electroacupuncture to inhibit ferroptosis.

Selenium Deficiency Causes Iron Death and Inflammatory Injury Through Oxidative Stress in the Mice Gastric Mucosa.

Selenium (Se) is a trace element essential for the maintenance of normal physiological functions in living organisms. Oxidative stress is a state in which there is an imbalance between oxidative and antioxidant effects in the body. A deficiency of Se can make the body more inclined to oxidation, which can induce related diseases. The aim of this experimental study was to investigate the mechanisms by which Se deficiency affects the digestive system through oxidation. The results showed that Se deficiency treatment led to a decrease in the levels of GPX4 and antioxidant enzymes and an increase in the levels of ROS, MDA, and lipid peroxide (LPO) in the gastric mucosa. Oxidative stress was activated. Triple stimulation of ROS, Fe2+, and LPO induced iron death. The TLR4/NF-κB signaling pathway was activated, inducing an inflammatory response. The expression of the BCL family and caspase family genes was increased, leading to apoptotic cell death. Meanwhile, the RIP3/MLKL signaling pathway was activated, leading to cell necrosis. Taken together, Se deficiency can induce iron death through oxidative stress. Meanwhile, the production of large amounts of ROS activated the TLR4/NF-κB signaling pathway, leading to apoptosis and necrosis of the gastric mucosa.

Exploring the prognostic significance of iron death­related lncRNAs in colorectal cancer: A systematic review and meta­analysis.

Colorectal cancer is a significant health challenge globally, with its prognosis associated with the profile of molecular biomarkers. Recently, the role of iron death-associated long non-coding (lnc)RNAs in cancer development has garnered attention; however, their expression patterns and prognostic value in colorectal cancer remain poorly elucidated. The present study aimed to assess the expression levels of iron death-related lncRNAs in colorectal cancer tissues and evaluate their relationship with patient outcomes through a comprehensive meta-analysis. Systematic searches were performed across multiple databases, including PubMed, Embase, Web of Science, Cochrane Library, CNKI, Wanfang and VIP databases, to identify studies relevant to the objective of the present study. Selected studies met predetermined inclusion criteria, from which data were extracted. R software version 4.3.1 was used for the meta-analysis, evaluating the association between iron death-related lncRNAs expression and colorectal cancer prognosis. Publication bias was assessed using funnel plot analysis, and Begg's and Egger's test. A total of 11 studies, including 3,984 patients with colorectal cancer, were included in the present meta-analysis. The results demonstrated a significant association between iron death-related lncRNAs and tumor stage classification [odds ratio (OR)=2.00; 95% confidence interval (CI), 1.77-2.24]. Notably, a significant association was also revealed between iron death-related lncRNAs and T stage classification in colorectal cancer (OR=1.82; 95% CI, 1.50-2.20). Furthermore, a statistically significant association was demonstrated between iron death-related lncRNAs and lymph node metastasis in colorectal cancer (OR=1.31; 95% CI, 1.03-1.66). The findings also highlighted a significant association between iron death-associated lncRNA and distant metastasis in colon cancer (OR=2.04; 95% CI, 1.62-2.56). Moreover, a significant association between iron death-related lncRNAs and risk score in colorectal cancer was revealed (OR=1.75; 95% CI, 1.25-2.46). In conclusion, the findings of the present meta-analysis underscore the potential of high ferroptosis-associated lncRNA expression as an indicator of adverse outcomes in colorectal cancer, suggesting their viability as biomarkers for cancer progression and prognosis. This insight opens potential new avenues for clinical application and further research into colorectal cancer management.

Tsc22d3 promotes morphine tolerance in mice through the GPX4 ferroptosis pathway.

BACKGROUND: Morphine tolerance refers to gradual reduction in response to drug with continuous or repeated use of morphine, requiring higher doses to achieve same effect. METHODS: The morphine tolerance dataset GSE7762 profiles, obtained from gene expression omnibus (GEO) database, were used to identify differentially expressed genes (DEGs). Weighted Gene Co-expression Network Analysis (WGCNA) was applied to explore core modules of DEGs related to morphine tolerance. Core genes were input into Comparative Toxicogenomics Database (CTD). Animal experiments were performed to validate role of Tsc22d3 in morphine tolerance and its relationship with ferroptosis-related pathway. RESULTS: 500 DEGs were identified. DEGs were primarily enriched in negative regulation of brain development, neuronal apoptosis processes, and neurosystem development. Core gene was identified as Tsc22d3. Tsc22d3 gene-associated miRNAs were mmu-miR-196b-5p and mmu-miR-196a-5p. Compared to Non-morphine tolerant group, Tsc22d3 expression was significantly upregulated in Morphine tolerant group. Tsc22d3 expression was upregulated in Morphine tolerant+Tsc22d3_OE, expression of HIF-1alpha, GSH, GPX4 in GPX4 ferroptosis-related pathway showed a more pronounced decrease. As Tsc22d3 expression was downregulated in Morphine tolerant+Tsc22d3_KO, expression of HIF-1alpha, GSH, GPX4 in GPX4 ferroptosis-related pathway exhibited a more pronounced increase. Upregulation of Tsc22d3 in Morphine tolerant+Tsc22d3_OE led to a more pronounced increase in expression of apoptosis proteins (P53, Caspase-3, Bax, SMAC, FAS). The expression of inflammatory factors (IL6, TNF-alpha, CXCL1, CXCL2) showed a more pronounced increase with upregulated Tsc22d3 expression in Morphine tolerant+Tsc22d3_OE. CONCLUSIONS: Tsc22d3 is highly expressed in brain tissue of morphine-tolerant mice, activating ferroptosis pathway, enhancing apoptosis, promoting inflammatory responses in brain cells.

A Mechanism Study on the Antioxidant Pathway of Keap1-Nrf2-ARE Inhibiting Ferroptosis in Dopaminergic Neurons.

BACKGROUND: The pathology of Parkinson's disease (PD) indicates that iron deposition exists in dopaminergic neurons, which may be related to the death of cellular lipid iron peroxide. The extracellular autophagy adaptor SQSTM1(p62) of dopamine (DA) neurons can activate the intracellular Keap1-Nrf2-ARE signaling pathway to inhibit ferroptosis, which has a protective effect on DA neurons. OBJECTIVE: The objective of this study was to investigate the protective mechanism of the Keap1-Nrf2-ARE antioxidant pathway against iron death in dopaminergic neurons. METHODS: The experiment was divided into a control group (Control group), 1-methyl-4-phenylpyridiniumion control group (MPP+ Control group), p62 overexpression group (MPP+OV-p62), and p62 overexpression no-load group (MPP+ OV-P62-NC). The inhibitors brusatol and ZnPP inhibited the activation of NF-E2-related factor 2(Nrf2) and Heme oxygenase-1(HO-1), respectively, and were divided into brusatol group (MPP+OV-p62+brusatol) and ZnPP group (MPP+OV-p62+ZnPP). RT-qPCR was used to detect transfection efficiency, and Cell Counting Kit-8 (CCK8) was used to detect cell activity. FerroOrange, 2,7-Dichlorodihydrofluorescein diacetate (DCFH-DA), and Liperfluo probes were used to detect intracellular iron, reactive oxygen species (ROS), and lipid peroxidation (LPO) levels. Western Blotting detected the levels of Nrf2, HO-1, Kelch-like ECH-associated protein1 (Keap1), and their downstream Glutathione peroxidase 4(GPX4) and Acyl-CoA synthetase long-chain family member 4(ACSL4). The levels of L-Glutathione (GSH) and Malondialdehyde (MDA) were detected by GSH and MDA kits, and the activation of Keap1-Nrf2-ARE pathway was verified at the cellular level to have an antioxidant protective effect on iron death in dopaminergic neurons. RESULTS: (1) The results of RT-qPCR showed that compared with the control group, the expression of the p62 gene was significantly increased in the MPP+OV-p62 groups (p = 0.039), and the p62 gene was significantly increased in the brusatol and ZnPP groups, indicating successful transfection (p =0.002; p=0.008). (2) The immunofluorescence probe flow results showed that compared to the normal control group, the contents of three kinds of probes in MPP+ model group were significantly increased (p =0.001; p <0.001; p<0.001), and the contents of three kinds of probes in MPP+OV-p62 group were decreased compared to the MPP+ model group (p =0.004). The results indicated that the levels of iron, ROS, and LPO were increased in the MPP+ group and decreased in the MPP+OV-p62 group. (3) Compared with the control group, the expressions of Nrf2, HO-1, and GPX4 in the MPP+OV-p62 group were increased (p =0.007; p =0.004; p=0.010), and the expressions of Keap1 and ACSL4 in MPP+p62 overexpression group were decreased (p =0.017; p =0.005). Compared with the MPP+ control group, Nrf2 and GPX4 were increased in the MPP+OV-p62 group, and ACSL4 was decreased in the MPP+OV-p62 group (p =0.041; p <0.001; p <0.001). The results of the GSH and MDA kit showed that compared with the normal control group, the content of GSH in the MPP+ control group was decreased (p < 0.01), and the content of MDA was increased (p < 0.01). Compared with the MPP+ model group, GSH content was increased (P = 0.003), and MDA content was decreased in the MPP+OV-p62 group (p < 0.001). Nrf2, HO-1, and GPX4 increased in the MPP+p62 overexpression group but decreased in the brusatol group and ZnPP group (p < 0.001). CONCLUSION: Based on the transfection of P62 plasmid, it was found that P62 plasmid can inhibit the lipid peroxidation of iron death in dopaminergic nerve cells by activating the Nrf2 signaling pathway, thus playing a protective role in dopaminergic nerve cells.

UNC93B1 Mediates the Effects of cGAS-STING on ER Stress and Iron Death, and Reduces Renal Toxicity in Cadmium-Exposed Rats.

BACKGROUND: Long-term exposure to cadmium can induce renal toxicity in rats, leading to endoplasmic reticulum (ER) stress and iron death. Notably, in cadmium-exposed rats, there is an increased expression of UNC93B1 (unc-93 homolog B1). Consequently, our investigation aims to determine the impact of UNC93B1 on ER stress and iron death in cadmium-exposed rats by modulating the cGAS-STING (cyclic GMP-AMP synthase-stimulator of interferon genes) pathway. METHODS: A cadmium-exposed rat model was established by intrabacally injecting chromium chloride (5 mg/kg, once a day for 4 weeks), and the levels of UCd (urine cadmium), UNAG (urine N-acetyl-ß-D-glucosaminidase), and UCr (urine creatinine) in urine were assessed. A silent UNC93B1 lentivirus was constructed, and STING agonists were procured and administered to the rats. Subsequently, kidney tissues were extracted post-mortem, and pathological changes in renal tissue were observed through hematoxylin and eosin (HE) staining. The expression and mRNA levels of UNC93B1, cGAS, and STING were examined using western blot (WB) and polymerase chain reaction (PCR). Autophagy proteins (light chain 3 (LC3), Beclin-1, p62) were also assessed by WB. Additionally, iron concentration was determined using a kit, while oxidative stress markers (cytochrome oxidase subunit 2 (COX2), glutathione peroxidase 4 (GPX4), superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH)) were measured through enzyme-linked immunosorbent assay (ELISA). Furthermore, endoplasmic reticulum stress proteins (protein kinase RNA-like ER kinase (PERK), CCAAT enhance-binding protein homologous protein (CHOP), activating transcription factor-4 (ATF4)) were analyzed by WB. RESULTS: Wstaining, WB, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), ELISA, and HE staining collectively revealed a heightened expression of UNC93B1, cGAS, and STING, accompanied by increased levels of autophagy, oxidative stress, and ER stress in cadmium-exposed rats (p < 0.05). Nephrotoxicity exhibited a reduction following the inhibition of UNC93B1, leading to decreased levels of oxidative stress, autophagy, and ER stress (p < 0.05). Notably, this observed phenomenon was reversed upon the addition of STING agonists, suggesting that UNC93B1 might exert a nephroprotective effect in cadmium-exposed rats through modulation of the cGAS-STING pathway. CONCLUSIONS: The inhibition of UNC93B1 mitigates nephrotoxicity in cadmium-exposed rats, and this protective effect is mechanistically linked to the cGAS-STING pathway.

Research progress of glutathione peroxidase family (GPX) in redoxidation.

Maintaining the balance of a cell's redox function is key to determining cell fate. In the critical redox system of mammalian cells, glutathione peroxidase (GPX) is the most prominent family of proteins with a multifaceted function that affects almost all cellular processes. A total of eight members of the GPX family are currently found, namely GPX1-GPX8. They have long been used as antioxidant enzymes to play an important role in combating oxidative stress and maintaining redox balance. However, each member of the GPX family has a different mechanism of action and site of action in maintaining redox balance. GPX1-4 and GPX6 use selenocysteine as the active center to catalyze the reduction of H2O2 or organic hydroperoxides to water or corresponding alcohols, thereby reducing their toxicity and maintaining redox balance. In addition to reducing H2O2 and small molecule hydroperoxides, GPX4 is also capable of reducing complex lipid compounds. It is the only enzyme in the GPX family that directly reduces and destroys lipid hydroperoxides. The active sites of GPX5 and GPX7-GPX8 do not contain selenium cysteine (Secys), but instead, have cysteine residues (Cys) as their active sites. GPX5 is mainly expressed in epididymal tissue and plays a role in protecting sperm from oxidative stress. Both enzymes, GPX7 and GPX8, are located in the endoplasmic reticulum and are necessary enzymes involved in the oxidative folding of endoplasmic reticulum proteins, and GPX8 also plays an important role in the regulation of Ca2+ in the endoplasmic reticulum. With an in-depth understanding of the role of the GPX family members in health and disease development, redox balance has become the functional core of GPX family, in order to further clarify the expression and regulatory mechanism of each member in the redox process, we reviewed GPX family members separately.

Ferrostatin-1 post-treatment attenuates acute kidney injury in mice by inhibiting ferritin production and regulating iron uptake-related proteins.

Background: Acute kidney injury (AKI) is a common and serious medical condition with high morbidity and mortality. Recent research has highlighted ferroptosis, a novel form of programmed cell death, as a potential therapeutic target in mitigating renal tubular injury in AKI. Ferrostatin-1, a specific ferroptosis inhibitor, has been demonstrated to prevent renal injury through ferroptosis inhibition. Methods: Utilizing a murine AKI model, we investigated the effects of Ferrostatin-1 by administering it post-injury. Through high-throughput sequencing and pathological analysis, we focused on the critical role of ferroptosis-related pathways in the treatment. Results: Ferrostatin-1 post-conditioning effectively mitigated oxidative damage and reduced iron content associated with AKI. Additionally, critical ferroptosis-related proteins, such as GPX4, SLC7A11, NRF2, and FTH1, exhibited increased expression levels. In vitro, Ferrostatin-1 treatment of HK-2 cells significantly diminished lipid peroxidation and iron accumulation. Furthermore, Ferrostatin-1 was found to downregulate the PI3K signalling pathway. Conclusion: Ferrostatin-1 acted as a potential ferroptosis inhibitor with the capacity to enhance antioxidant defences. This study suggests that Ferrostatin-1 could serve as a promising novel strategy for improving the treatment of AKI and promoting recovery from the condition.

Identification of the potential ferroptosis key genes in lung cancer with bone metastasis.

Background: To identify the potential key genes of ferroptosis in the pathogenesis of lung cancer with bone metastasis (LCBM) by bioinformatics analysis to provide new targets for treating LCBM and an indicator for early monitoring. Methods: We first obtained differentially expressed genes (DEGs) associated with ferroptosis from the Gene Expression Omnibus (GEO) database. MiRWalk 2.0 was used to predict the key microRNAs (miRNAs) and construct related gene-miRNA interaction networks. The functional enrichment analysis of key miRNAs was performed using the miEAA database. Finally, the clinical data of 105 lung cancer patients were retrospectively analyzed, and logistic regression analysis was conducted to assess the relationship between serum alkaline phosphatase (ALP), neuron-specific enolase (NSE), and bone metastasis in lung cancer patients, and a receiver operating characteristic (ROC) curve was drawn. Results: We identified 15 ferroptosis-related genes that were differentially expressed in lung cancer bone metastasis. GO and KEGG enrichment analyses suggested that these genes may affect the oxidative stress response, hypoxia response, rough endoplasmic reticulum, mitochondrial outer membrane, iron-sulfur cluster binding, virus receptor activity, central carbon metabolism in cancer, the interleukin-17 (IL-17) signaling pathway, and other aspects to participate in the occurrence and development of lung cancer bone metastasis. Among the 105 lung cancer patients included in the study, 39 cases had bone metastasis, and the incidence rate was 37.14%. A high Eastern Cooperative Oncology Group (ECOG) score and serum ALP and NSE overexpression were associated with bone metastasis in patients with lung cancer. By assessing the risk of bone metastasis in patients with lung cancer, we found that the Area Under Curves (AUCs) of serum ALP and NSE alone and combined were >0.70. Conclusions: The differentially expressed ferroptosis-related genes and predicted miRNA regulatory network in lung cancer bone metastasis and the related functional enrichment analysis provide new targets for the treatment of lung cancer bone metastasis. At the same time, from a serological perspective, it was found that early monitoring of serum ALP and NSE expression in patients with lung cancer could be considered to assess the risk of bone metastasis in the future.

Leveraging diverse cell-death patterns to predict the clinical outcome of immune checkpoint therapy in lung adenocarcinoma: Based on muti-omics analysis and vitro assay.

Advanced LUAD shows limited response to treatment including immune therapy. With the development of sequencing omics, it is urgent to combine high-throughput multi-omics data to identify new immune checkpoint therapeutic response markers. Using GSE72094 (n = 386) and GSE31210 (n = 226) gene expression profile data in the GEO database, we identified genes associated with lung adenocarcinoma (LUAD) death using tools such as "edgeR" and "maftools" and visualized the characteristics of these genes using the "circlize" R package. We constructed a prognostic model based on death-related genes and optimized the model using LASSO-Cox regression methods. By calculating the cell death index (CDI) of each individual, we divided LUAD patients into high and low CDI groups and examined the relationship between CDI and overall survival time by principal component analysis (PCA) and Kaplan-Meier analysis. We also used the "ConsensusClusterPlus" tool for unsupervised clustering of LUAD subtypes based on model genes. In addition, we collected data on the expression of immunomodulatory genes and model genes for each cohort and performed tumor microenvironment analyses. We also used the TIDE algorithm to predict immunotherapy responses in the CDI cohort. Finally, we studied the effect of PRKCD on the proliferation and migration of LUAD cells through cell culture experiments. The study utilized the TCGA-LUAD cohort (n = 493) and identified 2,901 genes that are differentially expressed in patients with LUAD. Through KEGG and GO enrichment analysis, these genes were found to be involved in a wide range of biological pathways. The study also used univariate Cox regression models and LASSO regression analyses to identify 17 candidate genes that were best associated with mortality prognostic risk scores. By comparing the overall survival (OS) outcomes of patients with different CDI values, it was found that increased CDI levels were significantly associated with lower OS rates. In addition, the study used unsupervised cluster analysis to divide 115 LUAD patients into two distinct clusters with significant differences in OS timing. Finally, a prognostic indicator called CDI was established and its feasibility as an independent prognostic indicator was evaluated by Cox proportional risk regression analysis. The immunotherapy efficacy was more sensitive in the group with high expression of programmed cell death models. Relationship between programmed cell death (PCD) signature models and drug reactivity. After evaluating the median inhibitory concentration (IC50) of various drugs in LUAD samples, statistically significant differences in IC50 values were found in cohorts with high and low CDI status. Specifically, Gefitinib and Lapatinib had higher IC50 values in the high-CDI cohort, while Olaparib, Oxaliplatin, SB216763, and Axitinib had lower values. These results suggest that individuals with high CDI levels are sensitive to tyrosine kinase inhibitors and may be resistant to conventional chemotherapy. Therefore, this study constructed a gene model that can evaluate patient immunotherapy by using programmed cell death-related genes based on muti-omics. The CDI index composed of these programmed cell death-related genes reveals the heterogeneity of lung adenocarcinoma tumors and serves as a prognostic indicator for patients.

Sodium selenite (Na2SeO3) attenuates T-2 toxin-induced iron death in LMH cells through the ROS/PI3K/AKT/Nrf2 pathway.

T-2 toxin, is a monotrichous mycotoxin commonly found in animal feed and agricultural products that can damage tissues and organs through oxidative stress. Selenium is a trace element with favorable antioxidant effects. However, it is unclear whether T-2 toxin-induces ferroptosis in LMH cells and whether Na2SeO3 has a protective role in this process. To investigate the process of hepatic injury by T-2 toxin and its antagonistic effect by Na2SeO3, we used 20 ng/mL T-2 toxin as well as 160 nmol/L Na2SeO3 to treat the LMH cells. The results demonstrated that exposure to the T-2 toxin induced iron death by increasing the quantity of ROS, leading to oxidative damage, decreasing the quantities of SOD, GPx, and T-AOC, and increasing the accumulation of MDA and H2O2, which resulted in the accumulation of Fe2+ and the down-regulation of the manifestation of linked genes and proteins including FTH1, Gpx4, NQO-1, and HO-1. After the addition of Na2SeO3, the PI3K/AKT/Nrf2 pathway is activated by regulating the selenoproteins gene level, and the above abnormal changes are reversed. In summary, Na2SeO3 alleviated T-2 toxin-induced iron death via the PI3K/AKT/Nrf2 pathway. These study not only broaden the cytotoxic knowledge regarding T-2 toxin, but also serve as a foundation for the use of Na2SeO3 in daily life.

[Effect of iron death inhibitor on hypoxia/reoxygenation injury of cardiomyocytes and its mechanism].

OBJECTIVE: To investigate the effects of ferrostatin-1 (Fer-1) on cardiomyocyte hypoxia/reoxygenation injury and its mechanisms. METHODS: The original generation of myocardial cells were extracted from 1～3 d newborn SD rats, which were randomly divided into normal control group (control), hypoxia reoxygenation (H/R) group and hypoxia reoxygenation + iron death inhibitors group (H/R + Fer-1). After 52 h of culture, cells in H/R group were added with 4 mmol/L Na2S2O4 solution. After 1 h of hypoxia, cells were reoxygenated with DMEM medium containing 10% calf serum for 3 h.The H/R+ Fer-1 group was pretreated with Fer-1 (2 µmol/L) for 24 h and then subjected to hypoxia and reoxygenation. The release rate of lactate dehydrogenase (LDH) was measured by UV spectrophotometry, the cell survival rate was measured by CCK-8 method, SOD was measured by xanthine oxidase method, MDA was measured by chemical coloration, and the changes of mitochondrial membrane potential and reactive oxygen species (ROS) were observed by immunofluorescence. Western blot was used to detect the expressions of ACSL4 and GPX4. RESULTS: Compared with the control group, the cell activity, SOD release and MMP level were decreased (P＜0.05), the levels of LDH, MDA and ROS were increased (P＜0.05), the protein expression of ACSL4 was increased (P＜0.05), and the protein expression of GPX4 was decreased (P＜0.05) in H/R group. Compared with the H/R group, the cell activity, SOD release and MMP level were increased (P＜0.05), the level of LDH, MDA and ROS were decreased (P＜0.05), the protein expression of ACSL4 was decreased (P＜0.05), and the protein expression of GPX4 was increased (P＜0.05) in H/R+Fer-1 group. CONCLUSION: Fer-1 can inhibit the production of intracellular reactive oxygen species by regulating ACSL4 and GPX4, thereby alleviating the hypoxia and reoxygenation injury of primary cardiomyocytes caused by iron death.

Mechanism of iron death induced by high homocysteine via TRPC6/NF-κb in glomerular podiatocytes / 实用医学杂志

Objective To investigate the mechanism of iron death induced by TRPC6/NF-κB in glomerular podiocytes mediated by high homocysteine(Hcy).Methods Mouse glomerulopocytes were cultured in vitro and divided into Control group(0 μmol/L Hcy)and Hcy group(80 μmol/L Hcy).After 48h of intervention,Western blot was used to detect the expression levels of iron death related proteins GPX4 and SLC7A11 and TRPC6 and NF-κ B.Real-time quantitative fluorescence PCR(qRT-PCR)and immunofluorescence were used to detect the expression of TRPC6.The level of podocyte apoptosis was detected by flow cytometry.Malondialdehyde(MDA)assay kit was used to determine intracellular MDA levels.After transfection of TRPC6 interference fragment and TRPC6 negative control(NC),qRT-PCR was divided into Control,si-NC and si-TRPC6(Si-TRPC6-1,Si-TRPC6-2,Si-TRPC6-3).Western Blot was divided into Control,Hcy,si-NC+Hcy,si-TRPC6+Hcy.The expression of TRPC6 mRNA was detected by qRT-PCR.The expression levels of GPX4,SLC7A11,NF-κB and TRPC6 were detected by Western Blot.The level of podocyte apoptosis after interference was detected by flow cytometry.Results(1)Compared with Control group,the expression levels of iron death related proteins GPX4 and SLC7A11 in Hcy group were decreased,and the apoptosis rate was increased(P<0.05).(2)Compared with Control group,TRPC6 protein,mRNA levels and immunofluorescence expression were increased in Hcy group.The level of MDA and the expression of NF-κB signaling pathway protein increased in Hcy group,and the comparison between the two groups had statistical significance(P<0.05).(3)Compared with the si-NC group,the mRNA expression level of TRPC6 in si-TRPC6(Si-TRPC6-1,Si-TRPC6-2,Si-TRPC6-3)group was decreased,and the interference effect of Si-TRPC6-3 was the best(P<0.05).After transfecting TRPC6 NC and TRPC6 interference fragment and administering Hcy,there was no difference in GPX4,SLC7A11,NF-κB and TRPC6 expression in si-NC+Hcy group compared with Hcy group.Compared with the si-NC+Hcy group,the si-TRPC6+Hcy group had higher expression of iron death related proteins,GPX4 and SLC7A11,lower expression of NF-κB and TRPC6,and decreased apoptosis rate(P<0.05).Conclusion This study confirmed that TRPC6/NF-κB can regulate iron death of renal podocytes under the induc-tion of Hcy,which is one of the mechanisms leading to kidney injury.

Effects of ursolic acid on iron death in endometrial stromal cells via JAK2/STAT3 signaling pathway / 中华内分泌外科杂志

Objective:To investigate the effects of ursolic acid (UA) on proliferation, migration and iron death of ectopic endometrial stromal cells (EESCs) and its mechanism.Methods:Mouse model of endometriosis was established and the primary EESCs were isolated. The cells were treated with UA at different concentrations (0, 2.5, 5, 10, 20, 40, 50, 80, 100, 200 μmol/L). The cells were divided into Control group (normal culture), 2.5 μmol/L UA group (2.5 μmol/L UA treatment), 5.0 μmol/L UA group (5.0 μmol/L UA treatment), 10.0 μmol/L UA group (10 μmol/L UA treatment), and UA+DUSP19 group (10 μmol/L UA+50 μmol/L JAK2/STAT3 signal pathway activator DUSP19 treatment). Cell survival rate was detected by CCK-8 method. Cell proliferation was detected by plate cloning method. Transwell chamber assay was used to detect cell migration. The levels of Fe 2+ and the contents of malondialdehyde (MDA), reactive oxygen species (ROS) and superoxide dismutase (SOD) were detected by kit. Protein expression levels of Ki67, PCNA, CyclinD1, p-JAK2, p-STAT3, JAK2 and STAT3 were detected by western blot. Results:The number of clones in Control, 2.5 μmol/L UA, 5.0 μmol/L UA and 10.0 μmol/L UA groups were as follows: 152.22±15.47, 121.22±11.54, 92.00±5.54, 66.44±6.88; Ki67 protein expression was 1.08±0.10, 0.73±0.07, 0.61±0.06, 0.45±0.02, respectively; The expression of PCNA protein was 0.85±0.07, 0.64±0.05, 0.41±0.03, 0.31±0.05, respectively; CyclinD1 protein expression levels were 0.98±0.11, 0.65±0.06, 0.51±0.05, 0.42±0.07, respectively. The migration numbers were 92.78±6.27, 62.22±2.20, 50.22±4.59 and 39.11±4.33, respectively; Fe 2+ levels were (1.06±0.07) μmol/g, (1.21±0.11) μmol/g, (1.33±0.08) μmol/g, (1.47±0.09) μmol/g, respectively; MDA content was (0.48±0.06) μmol/g, (0.65±0.07) μmol/g, (0.85±0.08) μmol/g, (1.03±0.11) μmol/g, respectively; ROS contents were (19.85±1.21) %, (24.83±2.79) %, (29.04±1.86) %, (33.87±2.45) %, respectively; SOD content were (36.41±3.56) U/mg, (31.03±2.81) U/mg, (25.63±2.84) U/mg, (19.62±1.67) U/mg, respectively; p-JAK2 protein expression was 0.85±0.10, 0.75±0.06, 0.53±0.05, 0.31±0.03, respectively; p-STAT3 protein expression was 1.08±0.11, 0.79±0.06, 0.63±0.07, 0.42±0.03, respectively. The p-JAK2 protein content in UA group and UA+DUSP19 group was 0.38±0.05 and 0.75±0.08, respectively; p-STAT3 protein expression was 0.46±0.04 and 0.80±0.03, respectively; The cell survival rates were (52.55±2.44) % and (82.18±4.72) %, respectively; Fe 2+ levels were (1.57±0.06) μmol/g and (1.21±0.13) μmol/g, respectively. The differences in the above indicators between the Control group and the 2.5 μmol/L UA group, 5.0 μmol/L UA group and 10.0 μmol/L UA group were statistically significant ( P<0.05). There were statistically significant differences among 2.5 μmol/L UA group, 5.0 μmol/L UA group and 10.0 μmol/L UA group ( P<0.05). There were statistically significant differences in p-JAK2, p-STAT3, cell survival rate and Fe 2+ levels between UA group and UA+DUSP19 group ( P<0.05) . Conclusion:Ursolic acid can inhibit the proliferation and migration of EESCs cells and induce iron death by regulating JAK2/STAT3 signaling pathway, thus playing a protective role in endometriosis.

Mechanism of ferroptosis in the formation of nonalcoholic fatty liver disease/nonalcoholic steatohepatitis / 临床肝胆病杂志

Ferroptosis is a type of iron-dependent cell death driven by lipid peroxidation, and its mechanism is associated with iron homeostasis imbalance, lipid peroxidation, and slC7A11-GSH-GPX4 antioxidant system. Ferroptosis plays a key role in the development and progression of nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH), and inhibition of ferroptosis can almost completely inhibit the development of NASH. This article reviews the research advances in the mechanism of ferroptosis and its role in NAFLD/NASH and proposes the research strategies and technical means for ferroptosis, so as to provide a reference for research on the mechanism of NAFLD/NASH.