Effects of perilla oil on the insulin sensitivity-related gene expression in skeletal muscle in insulin resistant rats / 中国比较医学杂志

Objective This study aims to investigate the effects of high-fat diet rich in perilla oil on the insulin sensitivity-related gene expression in skeletal muscle in insulin resistant rats.Methods The insulin resistant ( IR) rat models were randomly divided into 2 groups, including high fat group ( HF) and perilla oil ( PO) intervention group fed with 20%substitution of lard energy in the HF.The insulin sensitivity of rats was measured after 4 weeks.Theα-linolenic acid ( ALA) content of PO in the rat plasma were analyzed by gas chromatograph.Real-time PCR was applied to measure glucose transporter 4 ( GLUT4 ) and insulin receptor substrate-1 ( IRS-1 ) mRNA, and Western blot assay was used for detecting the expression of GLUT4 and IRS-1 in the skeletal muscle.Results At the gene and protein levels, PO remarkably reduced the level of IRS-1 and upregulated the level of GLUT4 with increasing intake of ALA and serum ALA content in IR rats.The results of hyperinsulinemic-euglycemic clamp test showed no significant difference between the two groups.Conclusions The results of our study suggest that consumption of n-3 PUFA at levels that can typically be found in the diet fed to IR rats in the form of ALA (0.556 g/d) may not improve insulin sensitivity, even though regulating the expression of GLUT4 and IRS-1 in the skeletal muscle.

Effects of perilla oil on the key gene expression regulating hepatic VLDL synthesis in obese rats / 中国实验动物学报

Objective This study aims to investigate the effects of high-fat diet rich in perilla oil on the expression of key genes that regulate hepatic VLDL synthesis in obese rats .Methods Sixty healthy male 5-week old SD rats were randomly divided into 2 groups.The rats in the normal control group (NC, n=12) were given normal diet, and the rats in the high fat group ( HF, n=48) were given a pure high fat diet in order to induce rat models of obesity .In the intervention period, the obesity model rats were randomly divided into 4 subgroups including consistent high fat group (CHF) and three intervention groups depending on perilla oil substitution rate of lard in CHF:20%PO, 50%PO and 100%PO.The serum triglyceride (TG) of the rats was measured after 4 weeks.Real-time PCR was applied to measure microsomal triglyceride transfer protein ( Mtp) and apolipoprotein B ( Apob) mRNA, and western blot assay was used for detecting the expression of MTP and APOB in the liver .Results Compared with the NC group , the CHF rats exhibited significantly high fat deposi-tion.The serum TG was markedly higher and the MTP and APOB were decreased at gene and protein levels in the CHF group compared with the NC group .After the intervention , PO remarkably reduced the level of serum TG and decreased he-patic fat deposition as it showed by pathological examination .At the gene and protein levels , MTP and APOB were upregu-lated by PO to different degrees .Conclusions All the three PO intervention can promote VLDL synthesis and secretion , and decrease the hepatic fat deposition in the obese rats .Furthermore , PO upregulates the expression of MTP at gene and protein levels in a dose-dependent manner .

The effects of Alpha-linolenic acid on the related key gene expressions of fatty acid synthesis in HepG2 cells / 中国比较医学杂志

Objective To investigate the effects of different doses Alpha-Linolenic acid ( ALA ) on the expressions of fatty acid synthesis-related genes in HepG2 cells.Methods HepG2 cells were divided into two groups, normal control group (NC) and high fat group (HF) in which cells were firstly cultured for 36h in the medium contained 0.5mmol/L stearic acid.Real-time quantitative PCR was taken to detect mRNA expression of genes SREBP1C, FAS and ACC which are related to fatty synthesis.While there are significant differences in fatty synthesis, 10%, 20%, 50%, 70% and 100%ALA took the place of stearic acid, 36h later, real-time quantitative PCR and Western blotting were taken to detect mRNA and protein expression of genes related to fatty synthesis.Results SREBP1C mRNA expression of ALA substitution groups were significantly lower than the high-fat group ( P <0.001) .The FAS of 0.5 mmol/L ALA group and 0.35 mmol/L ALA group were significantly lower than the high-fat group (P <0.001).ACC genes mRNA level was not significantly different from high-fat group.SREBP1C and FAS protein expression were significantly lower than the high-fat group, but ACC showed no significant difference.Conclusions Saturated fatty acids promote hepatocyte fatty acid synthesis, ALA abates fatty acid synthesis by inhibiting FAS and SREBP1C gene expression.