Ginsenoside Rg2 Protects Heart After Acute Myocardial Infarction by Regulating PI3K/Akt/mTOR Signaling Pathway
10.13422/j.cnki.syfjx.20242095
- VernacularTitle:人参皂苷Rg2调控PI3K/Akt/mTOR信号通路对急性心肌梗死后心脏保护作用
- Author:
Xixian ZHANG
1
;
Junjie SUN
2
;
Qingya LIU
2
Author Information
1. School of Basic Medicine and Forensic Medicine,Henan University of Science and Technology, Luoyang 471000,China
2. Henan University of Chinese Medicine,Zhengzhou 450046,China
- Publication Type:Journal Article
- Keywords:
ginsenoside Rg2;
myocardial infarction;
phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway;
autophagy;
myocardial remodeling;
cardiac protection
- From:
Chinese Journal of Experimental Traditional Medical Formulae
2025;31(10):185-193
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo investigate the cardioprotective effects of ginsenoside Rg2 in regulating the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway following acute myocardial infarction (AMI) in rats. Methods(1) Cellular experiment: Cardiomyocytes were isolated from 24-hour-old Sprague-Dawley (SD) neonatal rats and subjected to primary culture. An in vitro model of cardiomyocytes under an ischemic-hypoxic microenvironment was established. Cardiomyocytes were pretreated with ginsenoside Rg2 (1, 2, 3 mg·L-1) for 4 hours, then placed in RPMI 1640 serum-free medium and cultured for 24 hours in a three-gas incubator (94% N2, 5% CO2, 1% O2). The survival rate of cardiomyocytes was assessed using the methyl thiazolyl terazolium (MTT) assay. The levels of lactate dehydrogenase (LDH) leakage, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activity, and malondialdehyde (MDA) content in the cell culture supernatant were measured using spectrophotometry. (2) Animal experiment: Specific-pathogen-free (SPF) SD rats were used to establish an AMI model using the Olivette method combined with previous studies. Rats that survived 24 hours post-surgery were randomly divided into a model group and ginsenoside Rg2 high-, medium-, and low-dose groups. The normal and model groups received normal saline, while the ginsenoside Rg2 groups were administered intragastrically at doses of 8, 4, and 2 mg·kg-1, once daily for 3 days. The levels of SOD, MDA, and GSH-Px in myocardial tissues were detected. Cardiomyocyte apoptosis was assessed using the TdT-mediated dUTP biotin nick end labeling (TUNEL) assay. The mRNA and protein expression levels of PI3K, Akt, mTOR, p62, nuclear factor-κB p65 (NF-κB p65), and microtubule-associated protein 1 light chain 3 (LC3) Ⅱ/Ⅰ in myocardial tissues were analyzed using real-time quantitative polymerase chain reaction (Real-time PCR) and Western blot. Pathological changes in the infarct border zone were observed under a light microscope. Results(1) Cellular experiment: Compared with the normal group, the model group exhibited a significantly decreased cardiomyocyte survival rate, as well as reduced SOD and GSH-Px activity, whereas LDH activity and MDA content were significantly increased (P<0.05). Compared with the model group, ginsenoside Rg2 intervention significantly increased cardiomyocyte survival, SOD activity, and GSH-Px activity, while reducing LDH activity and MDA content (P<0.05) in a dose-dependent manner. Pathological examination revealed that ginsenoside Rg2 alleviated infarct size, myocardial degeneration, and necrosis, while significantly reducing cardiomyocyte apoptosis. (2) Animal experiment: Compared with the normal group, the model group exhibited significantly lower SOD and GSH-Px activity (P<0.05) and higher MDA content (P<0.05) in myocardial tissues. Compared with the model group, all ginsenoside Rg2 groups showed significantly increased SOD and GSH-Px activity (P<0.05) and reduced MDA content (P<0.05). Compared with the normal group, the model group exhibited significantly decreased mRNA and protein expression levels of PI3K, Akt, mTOR, p62,and LC3 Ⅱ/Ⅰ,whereas the expression levels of NF-κB p65 were significantly increased (P<0.05). Compared with the model group, the ginsenoside Rg2 groups showed significantly increased PI3K, Akt, mTOR, and p62 expression, while NF-κB p65 expression levels were significantly decreased (P<0.05) in a dose-dependent manner,the mRNA and protein expression levels of LC3 Ⅱ/Ⅰ in ginsenoside Rg2 high-dose groups were significantly increased(P<0.05). ConclusionGinsenoside Rg2 exerts cardioprotective effects following AMI in rats, potentially through the regulation of PI3K/Akt/mTOR-related protein expression.