RNAi-mediated silencing of mitofusin-2 gene induces glycometabolic disorder and insulin resistance in BALB/c mice
10.3760/cma.j.issn.1000-6699.2010.02.013
- VernacularTitle:RNAi介导线粒体融合素2基因沉默导致BALB/c小鼠葡萄糖代谢紊乱和胰岛素抵抗
- Author:
Xiaolin CHEN
;
Xiaoli CAI
;
Mingxia FAN
- Publication Type:Journal Article
- Keywords:
Mitofusin-2 gene;
Gene silencing;
Glycometabolism;
Insulin resistance
- From:
Chinese Journal of Endocrinology and Metabolism
2010;26(2):135-137
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the effects of RNA interference(RNAi)-mediated silencing of mitofusin-2 (Mfn2) gene on glycornetabolism and insulin resistance in BALB/c mice. Methods Mfn2 short hairpin RNA (shRNA) and negative control green fluorescent protein(GFP) -expressed plasmid vectors were constructed. 44 mice were randomly divided into transfection group (Mfn2) and negative control group (HK). 1.5 ml GFP-expressed plasmid(negative control or Mfn2 shRNA,75 μg for each mouse)was injected into the mice in 5 seconds through vena caudalis. Five days later, intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tolerance test(IPITT)were performed to evaluate glycometabolism and insulin sensitivity. D-3-[3~H]-glucose in PBS buffer were injected via the tail vein. Blood samples were taken at specific time points. Radioactivity was measured in all samples with liquid scintillation counter. The rates of hepatic glucose production in vivo were calculated. Mfn2 protein expression in hepatic tissue was detected by Western blot. Results Compared with HK mice, the Mfn2 expressions of Mfn2 mice decreased markedly(8.05±0.15 vs 8.56±0.01 ,P<0.05). The fasted blood glucose leves [(6.95±0. 83 vs 4.68±0. 29) mmol/L,P<0. 05] in Mfn2 mice were higher than those in HK mice. The insulin sensitivity of Mfn2 mice decreased markedly compared with HK mice. The rate of hepatic glucose production was significantly elevated in Mfn2 mice [(49.53±16.31)μmol·kg~(-1)·min~(-1)],compared with negative control mice[(24.91±4.07)μmol·kg~(-1)·min~(-1),P<0.05].Conclusion The down-regulatd expression of Mfn2 induces glycometabolic disorder and insulin resistance in BALB/c mice. Mfn2 plays an important role in maintaining glucose homeostasis in vivo.
