Targeting mPGES-2 to protect against acute kidney injury via inhibition of ferroptosis dependent on p53

Sodium Selenite Prevents Matrine-Induced Nephrotoxicity by Suppressing Ferroptosis via the GSH-GPX4 Antioxidant System

Matrine (MT), an active ingredient derived from Sophor flavescens Ait, is used as a therapeutic agent to treat liver disease and cancer. However, the serious toxic effects of MT, including nephrotoxicity, have limited its clinical application. Here, we explored the involvement of ferroptosis in MT-induced kidney injury and evaluated the potential efficacy and underlying mechanism of sodium selenite (SS) in attenuating MT-induced nephrotoxicity. We found that MT not only disrupts renal structure in mice but also induces the death of NRK-52E cells. Additionally, MT treatment resulted in significant elevations in ferrous iron, reactive oxygen species (ROS) and lipid peroxidation levels, accompanied by decreases in glutathione (GSH) and glutathione peroxidase (GPx) levels. SS effectively mitigated the alterations in ferroptosis-related indicators caused by MT and prevented MT-induced nephrotoxicity as effectively as Fer-1 in vivo and in vitro. SS also reversed the MT-induced reduction in GPX4, CTH and xCT protein levels. However, the glutathione peroxidase 4 (GPX4) inhibitor RSL3 and knockdown of GPX4, CTH, or xCT via siRNA abolished the protective effect of SS against MT-induced nephrotoxicity, indicating that SS exhibited antiferroptotic effects via the GSH-GPX4 antioxidant system. Overall, MT-induced ferroptosis triggers nephrotoxicity, and SS is a promising therapeutic drug for alleviating MT-induced renal injury by activating the GSH-GPX4 axis.

Human β-casein-derived peptide BCCY-1 improved the intestinal barrier integrity by regulating the TLR4/eNOS/3-Nitrotyrosine axis

Necrotizing enterocolitis (NEC) is a lethal gastrointestinal disease affecting premature infants. Although earlier studies have highlighted protective effects of milk-derived peptides against NEC, the role of the human β-casein-derived peptide BCCY-1 in intestinal barrier protection has never been investigated. Here, we showed that BCCY-1 alleviated the phenotype of NEC, reduced intestinal expression of Toll-like receptor 4 (TLR4) and interleukin-6, and improved the intestinal barrier integrity. NEC-associated multi-organ injury and impaired bone marrow hematopoiesis were also attenuated by BCCY-1. Metabolic screening revealed significant changes in intestinal metabolites in the NEC and NEC + BCCY-1 groups. Further analysis disclosed inhibition of 3-Nitrotyrosine formation due to the preservation of endothelial nitric oxide synthase (eNOS) activity, which was associated with the interactions between BCCY-1 and lipopolysaccharides, leading to disruption of TLR4 signaling. Our findings suggested that BCCY-1 improved intestinal barrier integrity through modulating the TLR4/eNOS/3-Nitrotyrosine axis, highlighting its potential role in the maintenance of intestinal health.

Exploring the role of ferroptosis-related genes as biomarkers in acute kidney injury

INTRODUCTION

Acute kidney injury (AKI) is a severe condition with high morbidity and mortality. Innovative biomarkers and treatments are essential for improving patient outcomes. This study aims to investigate the role of ferroptosis-related genes (FRGs) in AKI for identifying potential biomarkers and therapeutic targets.

METHODS

We analyzed mRNA expression profiles from the Gene Expression Omnibus (GEO: GSE139061) dataset, comparing 36 AKI samples with 9 normal samples. Differentially expressed genes (DEGs) were identified using the R software package limma. Functional enrichment analyses were conducted using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Key biomarkers were validated through area under the curve (AUC) values, and immune cell infiltration was analyzed using CIBERSORT.

RESULTS

We identified 78 differentially expressed FRGs, with 27 up-regulated and 51 down-regulated genes. Key signaling pathways included MAPK, ferroptosis, and p53. Five genes-NR4A1, GLRX5, USP35, AEBP2, and MDM4-were identified as potential biomarkers, each demonstrating AUC values greater than 0.800. Specifically, MDM4 showed significant potential by promoting the phosphorylation of p53 at Ser46, enhancing mitochondrial apoptotic activity. Immune analysis revealed a significant elevation of M0 macrophages in AKI samples compared to normal samples (P < 0.01).

CONCLUSION

Our findings highlight the critical role of ferroptosis-related genes in AKI, identifying NR4A1, GLRX5, USP35, AEBP2, and MDM4 as key biomarkers with high diagnostic potential. These results provide novel insights into the molecular mechanisms of AKI.

Mechanisms and therapeutic targets of ferroptosis: Implications for nanomedicine design

Ferroptosis is a nonapoptotic form of cell death and differs considerably from the well-known forms of cell death in terms of cell morphology, genetics, and biochemistry. The three primary pathways for cell ferroptosis are system Xc-/glutathione peroxidase 4 (GPX4), lipid metabolism, and ferric metabolism. Since the discovery of ferroptosis, mounting evidence has revealed its critical regulatory role in several diseases, especially as a novel potential target for cancer therapy, thereby attracting increasing attention in the fields of tumor biology and anti-tumor therapy. Accordingly, broad prospects exist for identifying ferroptosis as a potential therapeutic target. In this review, we aimed to systematically summarize the activation and defense mechanisms of ferroptosis, highlight the therapeutic targets, and discuss the design of nanomedicines for ferroptosis regulation. In addition, we opted to present the advantages and disadvantages of current ferroptosis research and provide an optimistic vision of future directions in related fields. Overall, we aim to provide new ideas for further ferroptosis research and inspire new strategies for disease diagnosis and treatment.

The role of ferroptosis in acute kidney injury: mechanisms and potential therapeutic targets

Acute kidney injury (AKI) is one of the most common and severe clinical renal syndromes with high morbidity and mortality. Ferroptosis is a form of programmed cell death (PCD), is characterized by iron overload, reactive oxygen species accumulation, and lipid peroxidation. As ferroptosis has been increasingly studied in recent years, it is closely associated with the pathophysiological process of AKI and provides a target for the treatment of AKI. This review offers a comprehensive overview of the regulatory mechanisms of ferroptosis, summarizes its role in various AKI models, and explores its interaction with other forms of cell death, it also presents research on ferroptosis in AKI progression to other diseases. Additionally, the review highlights methods for detecting and assessing AKI through the lens of ferroptosis and describes potential inhibitors of ferroptosis for AKI treatment. Finally, the review presents a perspective on the future of clinical AKI treatment, aiming to stimulate further research on ferroptosis in AKI.

Genetic or pharmacologic blockade of mPGES-2 attenuates renal lipotoxicity and diabetic kidney disease by targeting Rev-Erbα/FABP5 signaling

Diabetic kidney disease (DKD) is one of the most common complications of diabetes, and no specific drugs are clinically available. We have previously demonstrated that inhibiting microsomal prostaglandin E synthase-2 (mPGES-2) alleviated type 2 diabetes by enhancing β cell function and promoting insulin production. However, the involvement of mPGES-2 in DKD remains unclear. Here, we aimed to analyze the association of enhanced mPGES-2 expression with impaired metabolic homeostasis of renal lipids and subsequent renal damage. Notably, global knockout or pharmacological blockage of mPGES-2 attenuated diabetic podocyte injury and tubulointerstitial fibrosis, thereby ameliorating lipid accumulation and lipotoxicity. These findings were further confirmed in podocyte- or tubule-specific mPGES-2-deficient mice. Mechanistically, mPGES-2 and Rev-Erbα competed for heme binding to regulate fatty acid binding protein 5 expression and lipid metabolism in the diabetic kidney. Our findings suggest a potential strategy for treating DKD via mPGES-2 inhibition.