Abstract: Objective To investigate the role of mammalian sterile line 20-like kinas 1(MST1) and its regulatory mechanism in hepatic gluconeogenesis of mouse. Methods The mRNA expression of MST1 in the liver of db/db mice and db/m mice was detected by RT-qPCR. MST1 was overexpressed with adenovirus to detect glucose output capacity in mouse primary hepatocytes. Luciferase reporter assay was adopted to detect the effect of MST1 on phosphoenolpyruvate carboxykinase (PEPCK) promoter activity in HepG2 cells. Forkhead transcription factor O1 (FOXO1) was knocked down by interfering adenovirus in primary mouse liver cells to detect the effect of MST1 overexpression on the mRNA levels of PEPCK. Results The mRNA level of MST1 was significantly upregulated in the liver of db/db mice (P＜0.001). MST1 overexpression enhanced glucose output in mouse primary hepatocytes (P＜0.05). In HepG2 cells, MST1 overexpression increased the mRNA of PEPCK (P＜0.001) and the activity of PEPCK promoter (P＜0.01). Furthermore, MST1-induced increase in PEPCK mRNA was abolished when FOXO1 was knocked down by interfering adenovirus. Conclusions MST1 promotes hepatic gluconeogenesis by regulating the mRNA expression of PEPCK dependent on FOXO1.

Key words: hepatic gluconeogenesis, mammalian sterile 20-like kinase 1, phosphoenolpyruvate carboxykinase, forkhead transcription factor O1