Kim Y, Iwashita S, Tamura T, Tokuyama K, Suzuki M
Laboratory of Biochemistry of Exercise and Nutrition, University of Tsukuba, Japan.
Biochem Biophys Res Commun. 1995 Mar 28;208(3):1092-8. doi: 10.1006/bbrc.1995.1446.
To define the biochemical and molecular basis of high-fat diet to reduce insulin secretion, the present study examined the effect of high-fat diet on the gene expression of pancreatic GLUT2 and glucokinase. Rats were isoenergetically meal-fed a high-fat or a high-carbohydrate diet for 10 weeks. Plasma glucose concentration was higher, whereas insulin concentration was lower in the rats fed a high-fat diet than in the rats fed a high-carbohydrate diet. The level of GLUT2 and glucokinase mRNA in pancreas was significantly decreased in the rats fed a high-fat diet compared with a high-carbohydrate diet. The rates of reduction in plasma insulin level, pancreatic gene expression of GLUT2 and glucokinase by high-fat feeding were about 50%. These results suggest that high-fat feeding impairs signal transduction mechanism in pancreatic beta-cells to reduce insulin secretion in rats.
为确定高脂饮食降低胰岛素分泌的生化和分子基础,本研究检测了高脂饮食对胰腺葡萄糖转运蛋白2(GLUT2)和葡萄糖激酶基因表达的影响。将大鼠等能量分餐喂养高脂或高碳水化合物饮食10周。与喂养高碳水化合物饮食的大鼠相比,喂养高脂饮食的大鼠血浆葡萄糖浓度较高,而胰岛素浓度较低。与高碳水化合物饮食相比,高脂饮食喂养的大鼠胰腺中GLUT2和葡萄糖激酶mRNA水平显著降低。高脂喂养导致血浆胰岛素水平、胰腺GLUT2和葡萄糖激酶基因表达降低的幅度约为50%。这些结果表明,高脂喂养损害了大鼠胰腺β细胞中的信号转导机制,从而降低胰岛素分泌。