怀中1号地黄中2-phenylethyl-beta-glucopyranoside通过调节PI3K/Akt/mTOR/HIF-1α通路对低氧性肺动脉高压的影响

Effect of 2-phenylethyl-beta-glucopyranoside isolated from Huaizhong No.1 Rehmannia glutinosa on hypoxic pulmonary hypertension by regulating PI3K/Akt/m TOR/HIF-1αpathway

研究怀中1号地黄中2-phenylethyl-beta-glucopyranoside(Phe)对低氧诱导肺动脉高压小鼠的保护作用及其机制,为临床治疗肺动脉高压提供理论依据。首先将雄性C57BL/6N小鼠随机分为正常组,模型组,阳性药波生坦组(100 mg·kg^(-1)),Phe低、高剂量(20、40 mg·kg^(-1))组。除正常组外,其余各组均在10%的低氧环境中连续造模5周,并在第3周开始灌胃给药14 d,探究各组小鼠心肺功能、右心室压力、咳喘指数、肺部损伤、细胞凋亡、氧化应激相关指标、免疫细胞及磷脂酰肌醇3-激酶(phosphatidylinositol 3-kinase,PI3K)/蛋白激酶B(protein kinase B,Akt)/哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)/缺氧诱导因子(hypoxic inducible facter,HIF)^(-1)α通路相关蛋白或mRNA水平。接着进一步采用缺氧诱导肺动脉平滑肌细胞(pulmonary arterial smooth muscle cell,PASMC)合并PI3K激动剂(740Y-P)对Phe干预肺动脉高压的机制进一步探究。结果显示Phe可显著提高肺动脉高压小鼠的心肺功能,降低右心室压力、咳喘指数及肺部损伤,减少细胞凋亡、氧化应激相关指标及磷酸化蛋白激酶B(phosphorylated protein kinase B,p-Akt)、磷酸化哺乳动物雷帕霉素靶蛋白(phosphorylated mammalian target of rapamycin,p-mTOR)入核水平,抑制HIF^(-1)α和PI3K mRNA与蛋白表达水平,并维持小鼠机体免疫细胞稳态。进一步的机制探究中发现,Phe显著降低缺氧诱导PASMC的细胞活力与迁移能力,减少HIF^(-1)α和PI3K蛋白表达及p-Akt、p-mTOR入核水平,且此作用可被740Y-P阻断。因此,推测Phe可通过减轻肺组织氧化应激失衡与凋亡,调节免疫水平来发挥抗肺动脉高压作用,其机制可能和调控PI3K/Akt/mTOR/HIF^(-1)α通路有关。该研究以期为肺动脉高压的治疗提供药物参考及研究思路。

The study investigated the protective effect and mechanism of 2-phenylethyl-beta-glucopyranoside(Phe)from Huaizhong No.1 Rehmannia glutinosa on hypoxic pulmonary hypertension(PH),aiming to provide a theoretical basis for clinical treatment of PAH.Male C57BL/6N mice were randomly divided into normal group,model group,positive drug(bosentan,100 mg·kg^(-1))group,and low-and high-dose Phe groups(20 and 40 mg·kg^(-1)).Except for the normal group,all other groups were continuously subjected to model induction in a 10%hypoxic environment for 5 weeks,with oral administration for 14 days starting from the 3rd week.The cardiopulmonary function,right ventricular pressure,cough and asthma index,lung injury,cell apoptosis,oxidative stress-related indicators,immune cells,and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR)/hypoxic inducible factor 1α(HIF-1α)pathway-related proteins or mRNA levels were examined.Furthermore,hypoxia-induced pulmonary arterial smooth muscle cell(PASMC)were used to further explore the mechanism of Phe intervention in PH combined with PI3K ago-nist(740Y-P).The results showed that Phe significantly improved the cardiopulmonary function of mice with PH,decreased right ventricular pressure,cough and asthma index,and lung injury,reduced cell apoptosis,oxidative stress-related indicators,and nuclear levels of phosphorylated Akt(p-Akt)and phosphorylated mTOR(p-mTOR),inhibited the expression levels of HIF-1αand PI3K mRNA and proteins,and maintained the immune cell homeostasis in mice.Further mechanistic studies revealed that Phe significantly reduced the viability and migration ability of hypoxia-induced PASMC,decreased the expression of HIF-1αand PI3K proteins and nuc-lear levels of p-Akt and p-mTOR,and this effect was blocked by 740Y-P.Therefore,it is inferred that Phe may exert anti-PH effects by alleviating the imbalance of oxidative stress and apoptosis in lung tissues and regulating immune levels,and its mechanism may be related to the regulation of the PI3K/Akt/mTOR/HIF-1αpathway.This study is expected to provide drug references and research ideas for the treatment of PH.