Silencing PEG3 inhibits renal fibrosis in a rat model of diabetic nephropathy by suppressing the NF-κB pathway

CircBCL2L13 attenuates cardiomyocyte oxidative stress and apoptosis in cardiac ischemia‒reperfusion injury via miR-1246/PEG3 signaling

Ischemia‒reperfusion (I/R) is a common complication in the clinical treatment of acute myocardial infarction (MI), in which cardiomyocytes play a pivotal role in the recovery of cardiac function after reperfusion injury. The expression of numerous circular ribonucleic acids (circRNAs) is disrupted in I/R-induced cardiac damage, but the potential role of circRNAs in I/R damage has not been fully elucidated. The purpose of the present study was to clarify the biological action and molecular mechanism of circRNA 002166 (also termed circCL2L13) in postmyocardial I/R. Oxygen-glucose deprivation/reoxygenation (OGD/R) in an in vivo model was performed to simulate I/R damage. real-time polymerase chain reaction analysis was also conducted to evaluate the relationships of the SOD1, SOD2, NRF2, HO1 and GPX4 indicators with oxidative stress injury. TUNEL immunofluorescence was used to evaluate the degree of cardiomyocyte apoptosis in the different treatment groups. The circBCL2L13 level was markedly upregulated in myocardial tissues from a mouse I/R model. Overexpression of circBCL2L13 markedly attenuated the expression of oxidative stress-related genes and apoptosis in OGD/R-induced cardiomyocytes. A mechanistic study revealed that circBCL2L13 functions as a ceRNA for miR-1246 and modulates paternally expressed gene 3 (PEG3). Eventually, circBCL2L13 was proven to regulate PEG3 by targeting miR-1246, thereby protecting against OGD/R-induced cardiomyocyte oxidative damage and apoptosis. In conclusion, our study confirmed that the circBCL2L13/miR-1246/PEG3 axis suppressed the progression of OGD/R injury in cardiomyocytes, which might lead to new therapeutic strategies for cardiac I/R injury.

A systematic review of astragaloside IV effects on animal models of diabetes mellitus and its complications

Context

Diabetes mellitus (DM) is one of the fastest-growing diseases worldwide; however, its pathogenesis remains unclear. Complications seriously affect the quality of life of patients in the later stages of diabetes, ultimately leading to suffering. Natural small molecules are an important source of antidiabetic agents.

Objective

Astragaloside IV (AS-IV) is an active ingredient of Astragalus mongholicus (Fisch.) Bunge. We reviewed the efficacy and mechanism of action of AS-IV in animal and cellular models of diabetes and the mechanism of action of AS-IV on diabetic complications in animal and cellular models. We also summarized the safety of AS-IV and provided ideas and rationales for its future clinical application.

Methods

Articles on the intervention in DM and its complications using AS-IV, such as those published in SCIENCE, PubMed, Springer, ACS, SCOPUS, and CNKI from the establishment of the database to February 2022, were reviewed. The following points were systematically summarized: dose/concentration, route of administration, potential mechanisms, and efficacy of AS-IV in animal models of DM and its complications.

Results

AS-IV has shown therapeutic effects in animal models of DM, such as alleviating gestational diabetes, delaying diabetic nephropathy, preventing myocardial cell apoptosis, and inhibiting vascular endothelial dysfunction; however, the potential effects of AS-IV on DM should be investigated.

Conclusion

AS-IV is a potential drug for the treatment of diabetes and its complications, including diabetic vascular disease, cardiomyopathy, retinopathy, peripheral neuropathy, and nephropathy. In addition, preclinical toxicity studies indicate that it appears to be safe, but the safe human dose limit is yet to be determined, and formal assessments of adverse drug reactions among humans need to be further investigated. However, additional formulations or structural modifications are required to improve the pharmacokinetic parameters and facilitate the clinical use of AS-IV.

The nuclear factor kappa B signaling pathway is a master regulator of renal fibrosis

Renal fibrosis is increasingly recognized as a global public health problem. Acute kidney injury (AKI) and chronic kidney disease (CKD) both result in renal fibrosis. Oxidative stress and inflammation play central roles in progressive renal fibrosis. Oxidative stress and inflammation are closely linked and form a vicious cycle in which oxidative stress induces inflammation through various molecular mechanisms. Ample evidence has indicated that a hyperactive nuclear factor kappa B (NF-ƙB) signaling pathway plays a pivotal role in renal fibrosis. Hyperactive NF-ƙB causes the activation and recruitment of immune cells. Inflammation, in turn, triggers oxidative stress through the production of reactive oxygen species and nitrogen species by activating leukocytes and resident cells. These events mediate organ injury through apoptosis, necrosis, and fibrosis. Therefore, developing a strategy to target the NF-ƙB signaling pathway is important for the effective treatment of renal fibrosis. This Review summarizes the effect of the NF-ƙB signaling pathway on renal fibrosis in the context of AKI and CKD (immunoglobulin A nephropathy, membranous nephropathy, diabetic nephropathy, hypertensive nephropathy, and kidney transplantation). Therapies targeting the NF-ƙB signaling pathway, including natural products, are also discussed. In addition, NF-ƙB-dependent non-coding RNAs are involved in renal inflammation and fibrosis and are crucial targets in the development of effective treatments for kidney disease. This Review provides a clear pathophysiological rationale and specific concept-driven therapeutic strategy for the treatment of renal fibrosis by targeting the NF-ƙB signaling pathway.

Blocking AURKA with MK-5108 attenuates renal fibrosis in chronic kidney disease

Renal fibrosis, a common feature of chronic kidney disease (CKD), is characterized by excessive deposition of extracellular matrix (ECM) leading to scar formation in the renal parenchyma. Active epithelial-mesenchymal communication (EMC), and the proliferation and activation of fibroblasts are implicated in the causation of renal fibrosis. Aurora-A kinase (AURKA) is a serine/threonine kinase required for the process of mitosis. Dysregulation of AURKA has been demonstrated in the context of various cancers. However, the role of AURKA in CKD-associated fibrosis has not been elucidated. MK-5108, a potent and highly selective AURKA inhibitor, was shown to exhibit anti-cancer activity in recent preclinical and clinical studies. In the present study, we investigated the role of MK-5108 in renal fibrosis employing animal and cell models. In vivo, AURKA was highly expressed in fibrotic kidneys of CKD patients and in mouse kidneys with unilateral ureteral obstruction (UUO). Post treatment with MK-5108 at the 3rd day after UUO remarkably alleviated renal fibrosis, possibly by inhibiting the proliferation and activation of fibroblasts and suppressing the phenotypic transition of renal cells. Moreover, the enhanced inflammatory factors in obstructive kidneys were also repressed. In vitro, MK-5108 treatment inhibited the pro-fibrotic response in renal cells induced by transforming growth factor-β1. Finally, overexpression of AURKA in renal fibroblasts promoted fibrotic response, while silencing AURKA showed anti-fibrotic effect, further confirming the pro-fibrotic role of AURKA. In this study, inhibition of AURKA by MK-5108 markedly attenuated renal fibrosis. MK-5108 is a potential therapeutic agent for treatment of renal fibrosis in CKD.

MiR-1297 attenuates high glucose-induced injury in HK-2 cells via targeting COL1A2

BACKGROUND

In this study, we aimed to explore whether COL1A2 and miR-1297 participated in the progression of diabetic nephropathy (DN) in vitro and classified the underlying mechanisms.

METHODS

d-Glucose (30 mM; high glucose, HG)-stimulated HK-2 cells were used to mimic DN condition. RNA and non-coding RNA profiles were from Gene Expression Omnibus (GEO) database. The interaction between miR-1297 and COL1A2 was measured by dual-luciferase reporter assay. Gene Set Enrichment Analysis (GSEA) method was conducted to analyse COL1A2-associated signalling pathways. The role of miR-1297/COL1A2 in biological behaviours of HG-induced HK-2 cells were analysed by cell counting kit-8 and apoptosis assays.

RESULTS

Bioinformatics analysis revealed that COL1A2 was up-regulated in DN tissues. We predicted and verified miR-1297 as the regulatory miRNA of COL1A2, and the expression of miR-1297 was decreased in DN tissues and HG-stimulated HK-2 cells. Overexpression of miR-1297 could promote cell proliferation and inhibit apoptosis to protect HK-2 cells from HG-induced damage. And knockdown of COL1A2 enhanced the protective effects of miR-1297 on HG-stimulated HK-2 cells. GSEA results revealed that several inflammatory pathways were enriched in COL1A2 high-expression group. Meanwhile, transfection of miR-1297 reduced the phosphorylation of NFκB and expression of three important pro-inflammatory genes including cytokine CCL5, adhesion molecules ICAM1 and VCAM1 via targeting COL1A2. These results suggested that miR-1297 protected HG-treated HK-2 cells probably through suppressing inflammation via targeting COL1A2.

CONCLUSION

This study sheds a light on the role miR-1297/COL1A2 in DN progression and provides a novel promising therapy strategy for suppressing DN progression.