Variations in adrenal gland medulla and dopamine effects induced by the lack of Irs2

Types of cell death in diabetic cardiomyopathy: insights from animal models

Approximately one-tenth of the global population is affected by diabetes mellitus, and its incidence continues to rise each year. In China, 1.4 million patients die from diabetes-related complications every year. Additionally, approximately 26% of patients with diabetes develop diabetic cardiomyopathy, with heart failure being one of the main causes of death in these patients. However, early detection of diabetic cardiomyopathy has proven to be difficult in a clinical setting; furthermore, there are limited guidelines and targeted means of prevention and treatment for this disease. In recent years, several studies have provided evidence for the occurrence of various forms of regulated cell death in diabetic myocardial cells, including apoptosis, necroptosis, ferroptosis, and cuproptosis, which are closely linked to the pathological progression of diabetic cardiomyopathy. Although most research on diabetic cardiomyopathy is currently in the animal trial phase, the inhibition of these regulatory cell death processes can limit or slow down the progression of diabetic cardiomyopathy. Therefore, this review discusses the appropriate animal experimental models currently available for diabetic cardiomyopathy and evaluates the roles of apoptosis, necroptosis, ferroptosis, and cuproptosis in diabetic cardiomyopathy. We hope to provide new methods and ideas for future research in diabetic cardiomyopathy.

Regeneration of Pancreatic β-Cells for Diabetes Therapeutics by Natural DYRK1A Inhibitors

The pathogenesis of diabetes mellitus is characterized by insulin resistance and islet β-cell dysfunction. Up to now, the focus of diabetes treatment has been to control blood glucose to prevent diabetic complications. There is an urgent need to develop a therapeutic approach to restore the mass and function of β-cells. Although exogenous islet cell transplantation has been used to help patients control blood glucose, it is costly and has very narrow application scenario. So far, small molecules have been reported to stimulate β-cell proliferation and expand β-cell mass, increasing insulin secretion. Dual-specificity tyrosine-regulated kinase 1A (DYRK1A) inhibitors can induce human β-cell proliferation in vitro and in vivo, and show great potential in the field of diabetes therapeutics. From this perspective, we elaborated on the mechanism by which DYRK1A inhibitors regulate the proliferation of pancreatic β-cells, and summarized several effective natural DYRK1A inhibitors, hoping to provide clues for subsequent structural optimization and drug development in the future.

The influence of the lack of insulin receptor substrate 2 (IRS2) on the thyroid gland

Involvement of IRS2 in the proliferative effects of IGF-I of follicular thyroid cells has been described, but there are no evidences for in vivo participation of IRS2. This study aimed to analyse the in vivo relevance of IRS2 in the proliferation and apoptosis of thyroid cells by immunocytochemical studies for PCNA, Ki67, and active-caspase-3 in thyroid cells of IRS2 knockout (IRS2-KO) mice, jointly to TUNEL assay. Thyroid hormones were lower in IRS2-KO mice than in their wild-type (WT) counterparts. Increases in the area, perimeter and diameter of thyroid follicles of IRS2-KO mice were observed, which also showed increased proliferation rate of follicular cells and decreased percentage of apoptotic cells that was more evident in the central than in the marginal region of the gland. Sex-related differences were also found, since the follicular epithelium height was higher in male than in female mice. The percentage of proliferating cells showed significant changes in male but not in female mice, and apoptotic cells were more abundant in female than in male IRS2-KO animals, without significant differences between WT-animals. Therefore, our results suggest that IRS2 could be involved in the maintenance of thyroid cells population and in the normal physiology of the thyroid gland.