MicroRNA-351 eases insulin resistance and liver gluconeogenesis via the PI3K/AKT pathway by inhibiting FLOT2 in mice of gestational diabetes mellitus

Abstract

Gestational diabetes mellitus (GDM) is known as different degree glucose intolerance that is initially identified during pregnancy. MicroRNAs (miRs) may be a potential candidate for treatment of GDM. Herein, we suggested that miR-351 could be an inhibitor in the progression of GDM via the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway. Microarray analysis was used to identify differentially expressed genes and predict miRs regulating flotillin 2 (FLOT2). Target relationship between miR-351 and FLOT2 was verified. Gestational diabetes mellitus mice were treated with a series of mimic, inhibitor and small interfering RNA to explore the effect of miR-351 on insulin resistance (IR), cell apoptosis in pancreatic tissues and liver gluconeogenesis through evaluating GDM-related biochemical indexes, as well as expression of miR-351, FLOT2, PI3K/AKT pathway-, IR- and liver gluconeogenesis-related genes. MiR-351 and FLOT2 were reported to be involved in GDM. FLOT2 was the target gene of miR-351. Gestational diabetes mellitus mice exhibited IR and liver gluconeogenesis, up-regulated FLOT2, activated PI3K/AKT pathway and down-regulated miR-351 in liver tissues. Additionally, miR-351 overexpression and FLOT2 silencing decreased the levels of FLOT2, phosphoenolpyruvate carboxykinase, glucose-6-phosphatase, fasting blood glucose, fasting insulin, total cholesterol, triglyceride, glyeosylated haemoglobin and homeostasis model of assessment for IR index (HOMA-IR), extent of PI3K and AKT phosphorylation, yet increased the levels of HOMA for islet β-cell function, HOMA for insulin sensitivity index and glucose transporter 2 expression, indicating reduced cell apoptosis in pancreatic tissues and alleviated IR and liver gluconeogenesis. Our results reveal that up-regulation of miR-351 protects against IR and liver gluconeogenesis by repressing the PI3K/AKT pathway through regulating FLOT2 in GDM mice, which identifies miR-351 as a potential therapeutic target for the clinical management of GDM.

Keywords: FLOT2; PI3K/AKT pathway; gestational diabetes mellitus; insulin resistance; liver gluconeogenesis; microRNA-351.