Targeting ferroptosis with miR-144-3p to attenuate pancreatic β cells dysfunction via regulating USP22/SIRT1 in type 2 diabetes

Background: Recently, ferroptosis has been implicated in the pathologic process of several diseases including type 2 diabetes mellitus (T2DM). However, molecular mechanisms underlying ferroptosis in T2DM remain obscure. Methods: Twenty four mice were included in this study. T2DM model mice were established by a high-fat diet combined with streptozotocin injection. INS-1 cells were stimulated with high glucose (HG). Cell viability was detected by CCK-8 kit. The levels of GSH, MDA, iron, and lipid ROS, and SOD activity, were detected by the corresponding kits. The interaction between miR-144-3p and USP22 was validated by dual-luciferase reporter assay. The relationship between USP22 and its substrate was verified using Co-IP and ubiquitination assays. The mRNA and protein expressions were examined by RT-qPCR and western blot, respectively. The functions of beta cells in vitro and in vivo were evaluated glucose-stimulated insulin secretion test and HOMA-beta, respectively. Results: Ferroptosis occurred in the pancreas ofT2DM mice and HG-induced INS-1 cells. Silencing miR-144-3p blocked the effect of HG on the cell viability and accumulation of lipid peroxides, thereby improving the insulin secretion in INS-1 cells. Mechanistically, USP22 is a direct target of miR-144-3p, which could stabilize SIRT1 expression, thereby suppressing ferroptosis. Overexpressing USP22 attenuated deleterious roles of HG in INS-1 cells; but its roles were reversed by up-regulating miR-144-3p. In vivo study demonstrated that miR-144-3p antagomir exerted an antihyperglycemic effect and regulated the ferroptosis-related proteins in the pancreas. Conclusion: The up-regulation of miR-144-3p suppressed USP22/SIRT1 to induce ferroptosis, which causes pancreatic beta cells dysfunction, thereby promoting T2DM development.

Automated summary

This study found that Ferroptosis occurred in T2DM and investigated its mechanisms. The up-regulation of miR-144-3p suppressed USP22/SIRT1, leading to Ferroptosis and subsequent dysfunction of pancreatic beta cells, thereby promoting the development of T2DM.