Neutralization of hexokinase 2-targeting miRNA attenuates the oxidative stress-induced cardiomyocyte apoptosis

The role of glycolytic metabolic pathways in cardiovascular disease and potential therapeutic approaches

Cardiovascular disease (CVD) is a major threat to human health, accounting for 46% of non-communicable disease deaths. Glycolysis is a conserved and rigorous biological process that breaks down glucose into pyruvate, and its primary function is to provide the body with the energy and intermediate products needed for life activities. The non-glycolytic actions of enzymes associated with the glycolytic pathway have long been found to be associated with the development of CVD, typically exemplified by metabolic remodeling in heart failure, which is a condition in which the heart exhibits a rapid adaptive response to hypoxic and hypoxic conditions, occurring early in the course of heart failure. It is mainly characterized by a decrease in oxidative phosphorylation and a rise in the glycolytic pathway, and the rise in glycolysis is considered a hallmark of metabolic remodeling. In addition to this, the glycolytic metabolic pathway is the main source of energy for cardiomyocytes during ischemia-reperfusion. Not only that, the auxiliary pathways of glycolysis, such as the polyol pathway, hexosamine pathway, and pentose phosphate pathway, are also closely related to CVD. Therefore, targeting glycolysis is very attractive for therapeutic intervention in CVD. However, the relationship between glycolytic pathway and CVD is very complex, and some preclinical studies have confirmed that targeting glycolysis does have a certain degree of efficacy, but its specific role in the development of CVD has yet to be explored. This article aims to summarize the current knowledge regarding the glycolytic pathway and its key enzymes (including hexokinase (HK), phosphoglucose isomerase (PGI), phosphofructokinase-1 (PFK1), aldolase (Aldolase), phosphoglycerate metatase (PGAM), enolase (ENO) pyruvate kinase (PKM) lactate dehydrogenase (LDH)) for their role in cardiovascular diseases (e.g., heart failure, myocardial infarction, atherosclerosis) and possible emerging therapeutic targets.

MIR34A modulates lens epithelial cell apoptosis and cataract development via the HK1/caspase 3 signaling pathway

Cataracts are the leading cause of blindness in the world. Age is a major risk factor for cataracts, and with increasing aging, the burden of cataracts will grow, but the exact details of cataractogenesis remain unclear. A recent study showed that microRNA-34a (MIR34A) is involved in the development of cataracts, but the underlying pathogenesis remains obscure. Here, our results of microRNA target prediction showed that hexokinase 1 (HK1) is one of the genes targeted by MIR34A. Based on this finding, we focused on the function of MIR34A and HK1 in the progress of cataracts, whereby the human lens epithelial cell line SRA01/04 and mouse lens were treated with MIR34A mimics and HK1 siRNA. We found that HK1 mRNA is a direct target of MIR34A, whereby the high expression of MIR34A in the cataract lens suppresses the expression of HK1. In vitro, the upregulation of MIR34A together with the downregulation of HK1 inhibits the proliferation, induces the apoptosis of SRA01/04 cells, and accelerates the opacification of mouse lenses via the HK1/caspase 3 signaling pathway. In summary, our study demonstrates that MIR34A modulates lens epithelial cell (LEC) apoptosis and cataract development through the HK1/caspase 3 signaling pathway.

Icariin exhibits protective effects on cisplatin-induced cardiotoxicity via ROS-mediated oxidative stress injury in vivo and in vitro

BACKGROUND

Cisplatin-induced cardiotoxicity severely limits its clinical application as an antitumor drug and increases the risk of cardiovascular disease. Icariin (ICA), the main flavonoid isolated from Epimedii Folium, has been demonstrated to have various beneficial effects on cardiovascular disease. However, the protective effect of ICA against cisplatin-induced cardiotoxicity remains unclear.

PURPOSE

In present study, we explored the protective action of ICA against cisplatin-induced cardiotoxicity and its possible molecular mechanisms in vitro and in vivo.

METHODS

Mice were intraperitoneally injected with cisplatin 4 mg/kg every other day for 7 times to establish myocardial injury model. ICA (15, 30 mg/kg) was administered to mice by gavage for 21 days. H9c2 cells were treated with ICA (3, 6, 12 µM) in the presence or absence of cisplatin (40 µM), and then cell viability, oxidative stress, apoptosis, and mitochondrial function were evaluated.

RESULTS

Biochemical index detection and histopathological staining analysis showed that ICA had a good protective effect on cisplatin-induced cardiotoxicity. Cellular experiments showed that ICA inhibited cisplatin-induced oxidative stress in a dose-dependent manner by regulating the levels of glutathione peroxidase (GSH-Px), catalase (CAT), superoxide dismutase (SOD) and malondialdehyde (MDA). ICA could inhibit the expression of NF-κB and the secretion of inflammatory factors, thereby alleviating the inflammatory injury caused by cisplatin. In addition, ICA could alleviate cisplatin-induced myocardial injury by activating SIRT1 and PI3K/Akt signaling pathways and inhibiting MAPKs signaling pathway.

CONCLUSION

These results suggest that ICA could attenuate cisplatin-induced cardiac injury by inhibiting oxidative stress, inflammation and apoptosis, laying a foundation for ICA to reduce chemotherapy-induced cardiotoxicity in clinical practice.