RESUMO
ObjectiveTo observe the effects of modified Chaihu Shugansan（CHSG） and its disassembled formulas on angiotensin-converting enzyme 2 （ACE2）-angiotensin （Ⅰ-Ⅶ） ［Ang （Ⅰ-Ⅶ）］-mitochondrial assembly receptor （MasR） axis in hyperlipidemic rats with myocardial ischemia and depression， and to explore the underlying mechanism of its prevention and treatment of myocardial ischemia and depression. MethodA total of 108 male SD rats were randomly divided into a normal group， a model group， a modified CHSG group （11.7 g·kg-1）， a Quyu Huatan disassembled formula group （4.05 g·kg-1）， a Shugan Xingqi disassembled formula group （3.15 g·kg-1）， a Jianpi Yangxue disassembled formula group （4.5 g·kg-1）， a fluoxetine group （0.001 8 g·kg-1）， a trimetazidine group （0.005 4 g·kg-1）， and a simvastatin group （0.001 8 g·kg-1）， with 12 rats in each group. The hyperlipidemia model with myocardial ischemia and depression was induced with a high-fat diet combined with injection of isoproterenol （ISO） and chronic unpredictable mild stress （CUMS） in rats in the model group and groups with drug intervention for eight weeks. The rats in each group with drug intervention were treated correspondingly by gavage from the first day of modeling， while those in the normal group and the model group received the same amount of normal saline. The behavioral changes of rats in each group were observed by open field test and forced swimming test. Left ventricular fractional shortening （LVFS） and left ventricular ejection fraction （LVEF） were measured by echocardiography. The serum levels of total cholesterol （TC）， triglyceride （TG）， low-density lipoprotein cholesterol （LDL-C）， and high-density lipoprotein cholesterol （HDL-C） were detected by the enzyme-labeled apparatus. Hematoxylin-eosin （HE） staining was used to observe the histomorphological changes of the heart. The serum levels of angiotensin Ⅱ （AngⅡ）， ACE2， and Ang（Ⅰ-Ⅶ） were detected by enzyme-linked immunosorbent assay （ELISA）. The protein and mRNA expression of ACE2 and MasR in the hippocampus and the heart was detected by real-time quantitative polymerase chain reaction （Real-time PCR） and Western blot. ResultCompared with the normal group， the model group showed reduced movement time， distance， and average speed in the central area of the open field （P<0.01）， prolonged immobility time of rats in the forced swimming test （P<0.01）， decreased LVFS and LVEF （P<0.01）， inflammatory exudation and disorderly arranged fiber in heart tissues， elevated serum levels of TC， LDL-C， AngⅡ， ACE2 and Ang（Ⅰ-Ⅶ）， diminished HDL-C （P<0.01）， dwindled mRNA and protein expression of ACE2 in the hippocampus and the heart and MasR in the hippocampus， and up-regulated mRNA and protein expression of MasR in the heart （P<0.01）. Compared with the model group， the modified CHSG group displayed increased movement time， distance， and average speed in the center area of the open field （P<0.01）， shortened immobility time in the forced swimming test （P<0.01）， increased LVFS and LVEF （P<0.01）， relieved heart injury， reduced serum levels of TC， LDL-C， AngⅡ， ACE2， and Ang（Ⅰ-Ⅶ）， elevated level of HDL-C （P<0.01）， up-regulated mRNA and protein expression of ACE2 in the hippocampus and the heart and MasR in the hippocampus， and down-regulated mRNA and protein expression of MasR in the heart （P<0.01）. Each disassembled formula could improve the above indexes to a certain extent （P<0.05， P<0.01）， but the effect of the whole formula was optimal. ConclusionThe modified CHSG and its disassembled formulas have the effects of resisting depression， improving myocardial injury， and reducing blood lipid. Due to the synergistic effects of stasis-resolving/phlegm-eliminating drugs， liver-smoothing/Qi-moving drugs， and spleen-tonifying/blood-nourishing drugs in the formula， the modified CHSG is superior to each disassembled formula in efficacy. Its mechanism may be related to the activation of the ACE2-Ang （Ⅰ-Ⅶ）-MasR axis.