本文探讨了不同分子量普洱茶茶褐素对高脂血症SD大鼠的治疗作用。通过45 d的治疗，饲喂TB1和RTB的大鼠血清TCTG和LDL均显著低于高脂模型组（p<0.01），HDL显著高于高脂模型组（p<0.01），且TG与HDL与正常对照组无显著性差异。TB1和RTB对肝脏组织中HSL酶活性影响不显著，但在附睾组织和肠系膜组织中HSL活性极显著高于高脂模型组（p<0.01），与正常对照组差异不显著（p>0.01）。同时，TB1和RTB可显著抑制高脂血症大鼠脂肪组织ACC酶活性（p<0.01）和FAS酶活性（p<0.05）。说明TB1和RTB可通过提高HSL活性来加速脂质代谢，同时通过抑制ACC和FAS活性来减少脂肪酸合成。Western Blot检测发现，TB1和RTB有上调HSL蛋白表达、下调ACC1蛋白表达的作用。肝脏病理切片显示，TB1和RTB能有效减缓和降低高脂血症大鼠肝脏脂肪变性的速度和程度。研究结果表明，TB1是RTB的主要活性成分，对高脂血症大鼠有一定的治疗作用。

The therapeutic effect of Pu-erh tea theabrownins (TB) with different molecular weights to thehyperlipidemia in a Sprague-Dawley (SD) rat model was explored. After 45 d of treatment, the levels of serum total cholesterol (TC), triglycerides (TG), and low-density lipoprotein (LDL) of rats in the TB1 and crude TB (RTB) groups were significantly lower than those of the hyperlipidemia model group (p<0.01). Furthermore, the level of high-density lipoprotein (HDL) in these rats was significantly higher than that of hyperlipidemia model group (p<0.01); their TG and HDL levels were comparable to those of control rats. Enzymatic analysis showed that TB1 and RTB had no significant effect on the activity of hormone-sensitive lipase (HSL) in liver tissue. However, HSL activities in the epididymal and mesenteric tissues were significantly higher than those of the hyperlipidemia model group (p<0.01), and these activities were not significantly different (p>0.01) than those of the normal control. Furthermore, TB1 and RTB were able to significantly inhibit the activity of acetyl-CoA carboxylase (ACC) (p<0.01) and fatty acid synthase (FAS) (p<0.05) in the fatty tissue of hyperlipidemic rats. The results indicated that RTB and TB1 can increase HSL activity in the adipose tissue of hyperlipidemic rats to accelerate lipid metabolism and reduce fatty acid synthesis by inhibiting the activities of ACC and FAS. Western blot analysis demonstrated that TB1 and RTB could upregulate HSL protein expression and downregulate ACC1 protein expression. Liver biopsy showed that TB1 and RTB could also effectively reduce the rate and extent of hepatic steatosis in the hyperlipidemic rats. Together, the results showed that TB1 was the main active component of RTB and had certain therapeutic effects in hyperlipidemic rats.

国家自然科学基金项目(31260195)