小檗碱对高脂兔模型脂代谢及脂肪PPARγ、INSIG-2基因表达的影响

Effects of berberine on lipid metabolism and PPARγ、INSIG-2 gene expression in adipose tissue of hyperlipidemic rabbits

目的研究小檗碱对高脂兔模型脂代谢的影响,及其与脂肪代谢相关基因表达变化的相关性。方法采用高脂饲料喂养建立家兔高脂模型,测定各处理组血清TC、TG、LDL-C和HDL-C水平。实时荧光定量PCR技术检测脂肪组织PPARγ和INSIG-2基因表达。结果高脂组TC、TG和LDL-C水平较普食组明显升高(P<0.05),而小檗碱处理后血清TC、TG和LDL-C的水平较高脂组明显降低(P<0.05);实时荧光定量PCR检测结果显示,高脂组PPARγ和INSIG-2mRNA表达明显高于普食组(P<0.05),小檗碱处理后PPARγmRNA表达明显较高脂组显著降低(P<0.05),而INSIG-2mRNA表达则较高脂组明显上调(P<0.05),且低剂量作用更明显。结论小檗碱具有明显的降血脂作用,其机制与PPARγ表达下调而INSIG-2基因表达上调有关。

Objective To investigate the effects of berberine on lipids metabolism of hyperlipidemic rabbits, and to explore whether its mechanism was involved in the regulation of PPARγ and INSIG-2 gene expressions in adipose tissue. Methods The rabbit hyperlipidemie model was established by feeding with high fat diet. The levels of serum total cholesterol （TC）, triglycerides （TG） , low density lipoprorein-cholesterol （LDL-C） and high density lipoprotein-cholesterol （HDL-C） in each different treated group were determined. The mRNA ex- pressions of PPARγ and INSIG-2 in adipose tissue were quantified by real time quantitative PCR. Results The levels of serum TC, TG and LDL-C in high fat diet group obviously were elevated compared with those in normal diet group （ P 〈 0. 05 ）. Compared with those of the high fat diet group, the serum levels of TC, TG and LDL-C in berberine treated group were significantly decreased （ P 〈 0. 05 ）. The result of real time PCR demonstrated that the mRNA expressions of PPARγ and INSIG-2 in high fat diet group were significantly higher than those of the normal diet group （ P 〈 0.05 ）, while the PPARγ mRNA expression was inhibited and the INSIG-2 mRNA expression was up-regulated by berbefine （P 〈 0. 05 ）. Conclusions Berbefine can obviously decrease the blood lipid levels in the hyperlipidemie rabbits and its mechanisms may be related to the down-regulation of the PPA3,mRNA expression and up-regulation of the INSIG-2 mRNA expressions.