化瘀祛痰方药调控PI3K/AKT/mTOR信号通路改善高脂血症大鼠肝脏脂质代谢的机制

Mechanism of Huayu Qutan Formula on improving lipid metabolism in the liver of hyperlipidemia rats by regulating PI3K/AKT/mTOR signaling pathway

目的:以PI3K/AKT/mTOR信号通路为切入点探讨化瘀祛痰方改善高脂血症大鼠肝脏脂质损伤的分子机制。方法:40只SPF级雄性SD大鼠随机分为正常组、高脂血症组、化瘀祛痰方组及血脂康组(n=10)。正常组予正常饲料,其他组予高脂饲料,60 d后化瘀祛痰方组、血脂康组分别给予相应药物灌胃,其他组给予等体积磷酸盐缓冲0.9%氯化钠溶液灌胃30 d。HE与油红O染色观察大鼠肝脏形态变化;全自动生化分析仪检测血清血脂水平;Western Blot检测肝脏PI3K/AKT/mTOR通路蛋白表达。结果:高脂血症组大鼠肝脏脂肪变性明显,细胞肿胀,内含脂肪空泡及大量橘红脂滴,化瘀祛痰方组和血脂康组肝脏脂肪变性程度降低,脂质空泡及脂滴数明显减少;与正常组比较,模型组大鼠血清TC、TG、LDL-C水平显著升高(P<0.01),HDL-C水平显著降低(P<0.01),PI3K、AKT、mTOR蛋白表达水平显著上调(P<0.01),LC3A/B蛋白表达水平显著下调(P<0.01);与模型组比较,化瘀祛痰方组和血脂康组大鼠血清中TC、TG、LDL-C水平显著降低(P<0.05,P<0.01),HDL-C水平显著升高(P<0.01),PI3K、AKT、mTOR蛋白表达水平显著下调(P<0.05,P<0.01),LC3A/B蛋白表达水平显著上调(P<0.01)。结论:化瘀祛痰方可能通过调控PI3K/AKT/mTOR信号通路,增强高脂血症大鼠肝脏自噬,进而改善肝脏脂质损伤。

Objective: The PI3K/Akt/mTOR signaling pathway was used as the breakthrough point to explore the molecular mechanism of Huayu Qutan Formula to improve lipid damage in hyperlipidemia rats. Methods: A total of 40 SPF healthy male SD rats were randomly divided into control group, hyperlipidemia group, Huayu Qutan Formula group and Xuezhikang group(n=10). The control group was given control feed, and the other groups were given high-fat feed to establish the hyperlipidemia rat model. After 60 days of modeling, the groups of eliminating stasis and removing phlegm and Xuezhikang were given corresponding drugs by gavage, and the groups of control and hyperlipidemia were given equal volume of phosphate buffer physiological saline by gavage for 30 days. Morphological changes of rat liver were observed by HE and red oil O staining.The changes of serum lipid level of rats in each group were detected by automatic biochemical analyzer. The protein expression of PI3K/Akt/mTOR pathway in liver was detected by Western Blot. Results: Liver steatosis was obvious in hyperlipidemia group,with cell swelling, fat vacuoles and a large number of orange fat drops. Liver steatosis was reduced in Huayu Qutan Formula group and Xuezhikang group, and lipid vacuoles and fat drops were significantly reduced. Compared with the control group, the serum TC, TG and LDL-C levels in hyperlipidemia group were significantly increased(P<0.01), while the HDL-C level was significantly decreased(P<0.01), the protein expression levels of PI3K, Akt and mTOR were up-regulated(P<0.01), and LC3A/B protein expression was down-regulated(P<0.01);Compared with hyperlipidemia group, the levels of TC, TG and LDL-C in serum of Huayu Qutan Formula group and Xuezhikang group were significantly decreased(P<0.05, P<0.01), while the level of HDL-C was significantly increased(P<0.01), the protein expression levels of PI3K, Akt and mTOR were significantly down-regulated(P<0.05, P<0.01), and LC3A/B protein expression was up-regulated(P<0.01). Conclusion: Huayu Qutan Formula may enhance liver autophagy in hyperlipidemia rats by regulating PI3K/Akt/mTOR signaling pathway, and thereby improve liver lipid damage.