Role of uncoupling protein 2 in dexmedetomidine-induced alleviation of myocardial ischemia-reperfusion injury in diabetic mice
10.3760/cma.j.cn131073-20240731-00410
- VernacularTitle:解偶联蛋白2在右美托咪定减轻糖尿病小鼠心肌缺血再灌注损伤中的作用
- Author:
Jiahui DING
1
;
Hanzhong CAO
;
Jianjiang WU
;
Jiang WANG
Author Information
1. 南通大学附属肿瘤医院麻醉科，南通 226361
- Publication Type:Journal Article
- Keywords:
Dexmedetomidine;
Uncoupling protein 2;
Myocardial reperfusion injury;
Diabetes mellitus
- From:
Chinese Journal of Anesthesiology
2025;45(4):438-443
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate the role of uncoupling protein 2 in dexmedetomidine-induced alleviation of myocardial ischemia-reperfusion (I/R) injury in diabetic mice.Methods:SPF C57BL/6 male mice, aged 6-8 weeks, weighing 20-25 g, in which the model of type 2 diabetes mellitus was established by high-fat feeding combined with intraperitoneal injection of streptozotocin, were used in this study. Ninety diabetic mice were divided into 5 groups ( n=18 each) by a random number table method: sham operation group (S group), myocardial I/R group, myocardial I/R+ UCP2 inhibitor genipin group (I/R+ G group), myocardial I/R+ dexmedetomidine group (I/R+ D group) and myocardial I/R+ dexmedetomidine+ UCP2 inhibitor genipin group (I/R+ DG group). Myocardial I/R injury model was established by ligating the left anterior descending coronary artery of diabetic mice for 60 min followed by 120 min of reperfusion. Dexmedetomidine 20 μg/kg was intraperitoneally injected at 5 min prior to reperfusion in I/R+ D group. Genipin 100 mg/kg was intraperitoneally injected at 14 h prior to ischemia, and dexmedetomidine 20 μg/kg was intraperitoneally injected at 5 min prior to reperfusion in I/R+ D+ G group. The concentrations of cardiac troponin I (cTnI), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-10 in serum were detected by enzyme-linked immunosorbent assay at 120 min of reperfusion. The myocardial tissue was obtained for determination of the myocardial infarct size, the level of reactive oxygen species (ROS) (by flow cytometry), and the expression of UCP2, nuclear factor kappa B (NF-κB) inhibitory protein α (IκBα), phosphorylated IκBα (p-IκBα), NF-κB p65 and phosphorylated NF-κB p65 (p-NF-κB p65) (by Western blot) and for observation of the morphological structure of the myocardial tissue. The cardiac function was evaluated by echocardiography at 24 h of reperfusion. Results:Compared with group S, the percentage of myocardial infarct size and level of ROS were significantly increased, the concentrations of cTnI, TNF-α, IL-6 and IL-10 were increased, the expression of UCP2 was up-regulated, the p-IκBα/IκBα ratio and p-NF-κB p65/NF-κB p65 ratio were increased, the stroke volume (SV), ejection fraction (EF), and left ventricular fractional shortening (FS) were decreased ( P<0.05), and the myocardial structure was severely damaged in group I/R. Compared with group I/R, the percentage of myocardial infarct size and level of ROS were significantly decreased, the concentrations of cTnI, TNF-α and IL-6 were decreased, the concentration of IL-10 was increased, the expression of UCP2 was up-regulated, the p-IκBα/IκBα ratio and p-NF-κB p65/NF-κB p65 ratio were decreased, the SV, EF and FS were increased ( P<0.05), and the pathological damage was significantly attenuated in group I/R+ D. Compared with group I/R+ D, the percentage of myocardial infarct size and level of ROS were significantly increased, the concentrations of cTnI, TNF-α and IL-6 were increased, the concentration of IL-10 was decreased, the expression of UCP2 was down-regulated, the p-IκBα/IκBα ratio and p-NF-κB p65/NF-κB p65 ratio were increased, the SV, EF and FS were decreased ( P<0.05), and the pathological damage was aggravated in group I/R+ D+ G. Conclusions:Dexmedetomidine may ameliorate myocardial I/R injury by up-regulating UCP2 expression in the myocardium and inhibiting mitochondrial ROS-mediated inflammatory responses in diabetic mice.
