Relationship between trimethylamine N-oxide and high glucose-hypoxia/reoxygenation injury in rat cardiomyocytes and role of endoplasmic reticulum stress
10.3760/cma.j.cn131073-20241230-01118
- VernacularTitle:TMAO与大鼠心肌细胞高糖-缺氧复氧损伤的关系及ERS在其中的作用
- Author:
Qiang YAN
1
;
Guiping XU
;
Na QI
;
Xiaoli WANG
Author Information
1. 石河子大学医学院，石河子 832000
- Publication Type:Journal Article
- Keywords:
Methylamines;
Diabetes mellitus;
Myocardial reperfusion injury;
Myocytes, cardiac;
Endoplasmic reticulum stress
- From:
Chinese Journal of Anesthesiology
2025;45(11):1479-1484
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate the relationship between trimethylamine N-oxide (TMAO) and high glucose-hypoxia/reoxygenation (H/R) injury in rat cardiomyocytes and the role of endoplasmic reticulum stress (ERS).Methods:Normally cultured rat H9C2 cardiomyocytes were divided into 4 groups ( n=24 each) by using a table of random numbers: high glucose control group (HC group), high glucose-H/R group (H/R group), high glucose-H/R + TMAO group (T group), and high glucose-H/R + TMAO + 4-phenylbutyric acid group (P group). The high glucose-H/R injury model was established by incubating cells in high-glucose (25 mmol/L glucose) medium for 72 h, followed by 4 h of hypoxia in glucose-free medium and 4 h of reoxygenation in high-glucose medium. T group was incubated with 400 μmol/L TMAO for 72 h before hypoxia, and P group was incubated with 400 μmol/L TMAO and 1 mmol/L 4-phenylbutyric acid for 72 h before hypoxia. At 4 h of reoxygenation, the cell viability was detected by CCK-8 assay, the apoptosis rate, ROS level and opening of mitochondrial permeability transition pore (mPTP) were measured by flow cytometry, the mitochondrial membrane potential (MMP) was determined by JC-1 staining, the content of ATP was measured by luciferase method, and the expression of activating transcription factor 4 (ATF4), activating transcription factor 6 (ATF6), B-cell lymphoma 2-associated X protein (BAX), glucose-regulated protein 78 (GRP78), protein kinase R-like endoplasmic reticulum kinase (PERK) and inositol-requiring enzyme 1α (IRE1α) was detected by Western blot. Results:Compared with HC group, the cell survival rate, MMP and ATP levels were significantly decreased, the apoptosis rate, ROS level and opening of mPTP were increased, and the expression of ATF4, ATF6, BAX, GRP78, PERK and IRE1α was up-regulated in H/R group ( P<0.05). Compared with H/R group, the cell survival rate, MMP and ATP levels were significantly decreased, the apoptosis rate, ROS level and opening of mPTP were increased, the expression of ATF4, BAX, GRP78 and PERK was up-regulated ( P<0.05), and no statistically significant change was found in the expression of ATF6 or IRE1α in T group ( P>0.05). Compared with T group, the cell survival rate, MMP and ATP levels were significantly increased, and the apoptosis rate, ROS level and opening of mPTP was decreased, and the expression of ATF4, ATF6, BAX, GRP78, PERK and IRE1α was down-regulated in P group ( P<0.05). Conclusions:TMAO is involved in the underlying mechanism of high glucose-H/R injury in rat cardiomyocytes, which may be related to the excessive activation of the PERK pathway-mediated ERS and consequent exacerbation of mitochondrial dysfunction.
