Fig 1: Increased expression of miR-21 in pancreatic islets promotes Glut2 expression and glucose-stimulated insulin secretion.a, b Pancreatic islets were isolated from 7–8-week-old C57BL/6 male mice and infected with negative control virus (NC) or adenovirus over-expressing miR-21 (miR-21). Relative expression levels of miR-21 and Glut2 were determined by quantitative RT-PCR (a). Alternatively, virus infected islets were treated with 16.7 mM glucose and insulin level in the culture supernatant was determined by ELISA (b). Data are presented as means ± SD for n = 3 biologically independent samples. c, d Pancreatic islets were isolated from healthy donor and infected with negative control virus (NC) or adenovirus over-expressing miR-21 (miR-21). Expression of human miR-21 and Glut2 (c) and the level of glucose-stimulated secretion of insulin (d) were determined by quantitative RT-PCR and human insulin ELISA. Data are presented as means ± SD for n = 3 biologically independent samples. e, f Pancreatic islets were isolated from 7–8-week-old C57BL/6 male mice and infected with negative control virus (NC) or adenovirus over-expressing miR-21 under the control of mouse insulin promoter (Ins-miR-21). Expression of miR-21 and Glut2 (e) and the level of glucose-stimulated secretion of insulin (f) were determined by ELISA. Data are presented as means ± SD for n = 3 biologically independent samples. All statistical significance was analyzed using two-sided unpaired t test and P values are indicated in the figure. ns not significant. Data shown are representative results from at least two independent experiments. Source data are provided as a Source Data file.