FIGURE 3.

Overexpression of miR-483 induces insulin secretion but inhibits glucagon secretion via activated IRS2 signaling. A, insulin secretion was measured in MIN6 transfected with miR-483 mimic and control mimic, or anti-miR483 and anti-control at 25 mm glucose, or in isolated islets infected with recombinant adenovirus overexpressed miR-483 (AD-miR483) or control (Ad-GFP) at 16.7 mm glucose. B, glucagon secretion was analyzed in αTC1-6 transfected with miR-483 mimic or anti-miR483 at 1 mm glucose or in isolated islets infected with AD-miR483 at 2.7 mm glucose. Secreted insulin and glucagon levels in the medium were quantified using mouse insulin and glucagon ELISA, respectively, and normalized to total cellular DNA content and then presented as relative -fold. The presented data are the average of three independent experiments ± S.D. *, p < 0.05, **, p < 0.01 versus control. C–E, transfected cells were incubated with 1 or 25 mm glucose in DMEM for 16 h, and the expression of IRS2 and actin was analyzed by Western blot in MIN6 (C) and αTC1-6 (D) and isolated islets (E). All the experiments were repeated 3–6 times.