Potential pathogenic roles of ferroptosis and cuproptosis in cadmium-induced or exacerbated cardiovascular complications in individuals with diabetes

Dapagliflozin activates the RAP1B/NRF2/GPX4 signaling and promotes mitochondrial biogenesis to alleviate vascular endothelial ferroptosis

Vascular endothelial ferroptosis is a key mechanism underlying endothelial injury and atherosclerotic plaque formation. Dapagliflozin, an essential medication in the management of heart failure, has been shown to delay atherosclerosis progression. However, the underlying mechanisms remain unclear. This study aimed to elucidate the molecular pathways whereby dapagliflozin inhibits vascular endothelial ferroptosis. We utilized human umbilical vein endothelial cells (HUVECs) to construct a cell model of atherosclerosis combined with ferroptosis. Dapagliflozin significantly decreased the iron and malondialdehyde levels and the release of inflammatory factors in HUVECs treated with oxidized low-density lipoprotein or Erastin but increased the superoxide dismutase activity and the reduced glutathione / oxidized glutathione ratio. Results from transmission electron microscopy indicated that dapagliflozin alleviated the mitochondrial shrinkage and the reduction in the number of cristae in these HUVECs. RNA sequencing revealed that dapagliflozin upregulates RAP1B. In vitro experiments showed that RAP1B upregulates NRF2 and promotes its nuclear translocation, activating the xCT/GPX4 signaling pathway and inhibiting lipid peroxidation. Additionally, dapagliflozin induces mitochondrial biogenesis and enhances oxidative phosphorylation through the RAP1B/NRF2 pathway, reducing iron overload and excessive production of mitochondrial reactive oxygen species, ultimately mitigating ferroptosis. At the animal level, we constructed an atherosclerosis model by using Apoe-/-; Rap1b-/- double-knockout mice. Rap1b knockout blocked the inhibitory effects of dapagliflozin on atherosclerotic plaque formation and ferroptosis activation. We confirmed in vivo that dapagliflozin upregulates GPX4 and key factors of mitochondrial biogenesis via RAP1B, promoting oxidative phosphorylation. When mitochondrial oxidative phosphorylation was pharmacologically inhibited, ferroptosis was reactivated, promoting atherosclerotic plaque formation. In conclusion, this study demonstrated that dapagliflozin activates the RAP1B/NRF2/GPX4 signaling pathway and promotes mitochondrial biogenesis, thereby alleviating vascular endothelial ferroptosis.

Schisandrol B alleviated diabetic cardiac injury by inhibiting ferroptosis and improving lipid metabolism in mice

BACKGROUND

Diabetic cardiomyopathy (DCM) is a major complication of diabetes mellitus, highlighting the need to elucidate its pathogenesis and explore potential therapeutic interventions.

PURPOSE

This study aimed to investigate the cardioprotective mechanisms of SolB in DCM using metabolomic and transcriptomic approaches.

METHODS

A DCM mouse model was induced by a high-fat diet combined with streptozotocin (STZ) administration. Cardiac function was assessed, and myocardial structure was examined via echocardiography and HE staining after 10 weeks of SolB treatment. Serum metabolomics and cardiac transcriptomics were performed to identify differentially expressed metabolites and genes, respectively, followed by correlation analysis. Ferroptosis-related proteins were detected by Western blotting (WB). In vitro, H9c2 cells exposed to palmitic acid and high glucose were used to evaluate the effects of SolB on cell viability, ATP production, oxygen consumption, reactive oxygen species (ROS) levels, and mitochondrial membrane potential. Ferroptosis inducer and inhibitor were employed to further explore the underlying mechanisms.

RESULTS

SolB did not significantly alter blood glucose levels but markedly improved cardiac function and myocardial structure. Metabolomic analysis revealed that SolB modulated serum metabolic pathways, including carnitine synthesis and fatty acid oxidation et al. Transcriptomic data indicated that SolB influenced ferroptosis-related pathways. Integrated analysis demonstrated that SolB regulated fatty acid degradation, glutathione metabolism, and cysteine and methionine catabolism. In H9c2 cells, SolB enhanced cell viability, suppressed ferroptosis, reduced lactate dehydrogenase (LDH) release, and improved mitochondrial function.

CONCLUSIONS

SolB ameliorates diabetic myocardial injury by inhibiting ferroptosis and improving myocardial lipid metabolism.

6PPD impairs growth performance by inducing intestinal oxidative stress and ferroptosis in zebrafish

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), a tire-derived pollutant, has gained increasing attention due to its potential toxicity to aquatic organisms. Although previous studies have revealed that 6PPD impacts early developmental stages of larval fish, its effects on adult fish, particularly on key organs, remain unclear. In this study, we observed that adult zebrafish exposed to 6PPD exhibited reduced growth performance and increased fecal output. Histological examination with hematoxylin and eosin (H&E) staining revealed damage to the intestinal villi and a reduction in goblet cell numbers, indicating that 6PPD impairs growth performance by disrupting the digestive system. Comparative transcriptomic analysis revealed that 6PPD caused significant changes in the expression of 727 genes in the intestine, of which 280 genes were up-regulated and 447 genes were down-regulated. These genes were primarily associated with nutrient digestion and absorption, energy metabolism, immune response, and redox regulation. Mechanistically, 6PPD induced oxidative stress and triggered ferroptosis in the intestine, leading to structural damage of the intestinal villi. Treatment with the antioxidant N-acetylcysteine (NAC) alleviated 6PPD-induced oxidative stress and ferroptosis, thereby improving intestinal villi structure and promoting fish growth. This study provides insights into the mechanisms by which 6PPD impairs growth in adult zebrafish and highlights NAC as a potential therapeutic strategy to mitigate its toxicity.

Homocysteine induces endometrial ferroptosis via MAPK pathway in recurrent pregnancy loss

BACKGROUND

Recurrent pregnancy loss (RPL) with complex etiology and elevated homocysteinemia (HCY) has been recognized one of the risk factors, however the mechanism of HCY participation in RPL are not fully elucidated.

METHODS

Samples from RPL_HHCY, RPL_NHCY and controls were used to metabolomics and proteomic analysis. Cell counting kit-8 assay, EdU assay kit, wound healing assay and induced decidualization were performed to observe the HCY induced dysfunction of human endometrial stromal cells (hESCs). Intracellular ROS, lipid peroxidation, MDA, GSH and Fe2+ were examined. Western blotting was used to measure protein expression.

RESULTS

We found differential metabolites were enriched in glutathione metabolism, and differentially protein expression were enriched in the ferroptosis. In vitro, ferrostatin-1 (Fer-1) could improve the decrease of HCY induced cell viability, proliferation, migration and decidualization of hESCs, and reverse ROS, lipid peroxidation, MDA, GSH and Fe2+ levels. Also, Fer-1 enhanced GPX4 and SLC3A2, lightened ACSL4 protein expression. Gene Set Variation Analysis (GSVA) found MAPK is an important pathway for ferroptosis, and inhibition MAPK signaling pathway reversed the phosphor-ERK (p-ERK), p-JNK and p-P38 amplified by HCY.

CONCLUSIONS

Our findings implicate that HCY disturbs the function of hESCs by activation of the MAPK signaling pathway induced ferroptosis and may contribute to RPL. This provides a theoretical basis for the relationship between high HCY and RPL.

MiR-133a-5p Facilitates Cuproptosis in Hepatocellular Carcinoma Through Targeting of ATP7B

Purpose

We explored the effects of miR-133a-5p and ATP7B on cuproptosis in hepatocellular carcinoma.

Methods

Initially, we assessed the impact of miR-133a-5p on hepatocellular carcinoma (HCC) using CCK-8 assays, cell scratch assays, and flow cytometry. Subsequently, we utilized elesclomol in combination with copper ions to induce cuproptosis in the HCC cell lines PLC/PRF/5 and Huh-7. We evaluated the influence of miR-133a-5p on cuproptosis using CCK-8 assays, cell scratch assays, flow cytometry, and Western blotting. To elucidate the underlying mechanisms, we employed bioinformatics to identify potential downstream target genes of miR-133a-5p and conducted dual-luciferase reporter assays to confirm the binding sites. Finally, we validated the regulatory effect of miR-133a-5p on ATP7B by modulating miR-133a-5p expression through cell transfection experiments.

Results

The results from the CCK-8 assay, cell scratch assay, and flow cytometry demonstrated that miR-133a-5p significantly inhibits the proliferation and migration of HCC cells while promoting their apoptosis. Furthermore, Elesclomol in combination with copper ions induces cuproptosis in HCC cells. Compared to the cuproptosis observed in HCC as a control, miR-133a-5p further suppresses the proliferation and migration of HCC cells, enhances their death, and increases the expression of cuproptosis-related proteins more prominently. Bioinformatics analysis suggested that ATP7B might be a downstream target gene of miR-133a-5p. This was confirmed by dual luciferase assays, which identified a binding site between miR-133a-5p and ATP7B. Additionally, the expression levels of ATP7B were found to decrease or increase in response to the regulation by miR-133a-5p.

Conclusion

MiR-133a-5p facilitates cuproptosis in hepatocellular carcinoma through targeting of ATP7B.

From bench to bedside: targeting ferroptosis and mitochondrial damage in the treatment of diabetic cardiomyopathy

Diabetic cardiomyopathy (DCM) is a common and fatal cardiac complication caused by diabetes, with its pathogenesis involving various forms of cell death and mitochondrial dysfunction, particularly ferroptosis and mitochondrial injury. Recent studies have indicated that ferroptosis and mitochondrial damage play crucial roles in the onset and progression of DCM, though their precise regulatory mechanisms remain unclear. Of particular interest is the interaction between ferroptosis and mitochondrial damage, as well as their synergistic effects, which are not fully understood. This review summarizes the roles of ferroptosis and mitochondrial injury in the progression of DCM and explores the molecular mechanisms involved, with an emphasis on the interplay between these two processes. Additionally, the article offers an overview of targeted drugs shown to be effective in cellular experiments, animal models, and clinical trials, analyzing their mechanisms of action and potential side effects. The goal is to provide insights for future drug development and clinical applications. Moreover, the review explores the challenges and prospects of multi-target combination therapies and personalized medicine interventions in clinical practice to offer strategic guidance for the comprehensive prevention and management of DCM.