Liang Dongshi, Huang Airong, Jin Yimei, Lin Miaomiao, Xia Xiaojiao, Chen Xiaoli, Huang Airong
The Second Affiliated Hospital of Wenzhou Medical University Wenzhou 325027, P. R. China.
Am J Transl Res. 2018 May 15;10(5):1422-1430. eCollection 2018.
This study aimed to examine whether exogenous NaHS can protect myocardial mitochondrial injury from sepsis by enhancing the peroxisome proliferator-activated receptor gamma co-activator 1α (PGC-1α)/ nuclear factor erythroid-2-related factor 2 (NRF2) pathway and mitochondrial biosynthesis in mice. Animals were divided into sham-operated, sepsis, sepsis + 25 μmol/L NaHS, sepsis + 50 μmol/L NaHS, sepsis + 100 μmol/L NaHS, and sepsis + 200 μmol/L NaHS groups. The myocardial damage was evaluated by hematoxylin and eosin staining for myocardial microstructure and serum cardiac troponin I (cTnI) detection. The myocardial mitochondrial damage was evaluated through transmission electron microscopic observation of mitochondrial microstructure and detection of the degree of myocardial mitochondrial swelling. The adenosine triphosphate (ATP) level was used to appraise the mitochondrial function. The mRNA expression levels of Nrf2, PGC-1α, and Tfam were analyzed to explore the molecular mechanism.
In the sepsis group, the structure of myocardial tissue and mitochondria were significantly damaged, the serum cTnI level increased ( < 0.05), the ATP level reduced, the degree of myocardial mitochondrial swelling aggravated, and the mRNA expression levels of Nrf2, PGC-1α, and Tfam increased ( < 0.05). After NaHS treatment, the structure of myocardial tissue and mitochondria improved, the cTnI level reduced, the ATP level increased, the degree of myocardial mitochondrial swelling alleviated, and the mRNA expression level of Nrf2, PGC-1α, and Tfam increased continuously in a dose-dependent manner ( < 0.05).
Exogenous NaHS had a protective effect against myocardial mitochondrial injury in sepsis. The mechanism might lie in enhancing the PGC-1α/NRF2 pathway and mitochondrial biosynthesis.
本研究旨在探讨外源性硫化氢(NaHS)是否可通过增强过氧化物酶体增殖物激活受体γ辅激活因子1α(PGC-1α)/核因子E2相关因子2(NRF2)通路及线粒体生物合成来保护小鼠免受脓毒症所致的心肌线粒体损伤。将动物分为假手术组、脓毒症组、脓毒症+25μmol/L NaHS组、脓毒症+50μmol/L NaHS组、脓毒症+100μmol/L NaHS组和脓毒症+200μmol/L NaHS组。通过苏木精-伊红染色观察心肌微观结构及检测血清心肌肌钙蛋白I(cTnI)来评估心肌损伤。通过透射电子显微镜观察线粒体微观结构及检测心肌线粒体肿胀程度来评估心肌线粒体损伤。用三磷酸腺苷(ATP)水平评估线粒体功能。分析Nrf2、PGC-1α和线粒体转录因子A(Tfam)的mRNA表达水平以探究分子机制。
在脓毒症组中,心肌组织和线粒体结构明显受损,血清cTnI水平升高(<0.05),ATP水平降低,心肌线粒体肿胀程度加重,Nrf2、PGC-1α和Tfam的mRNA表达水平升高(<0.05)。NaHS治疗后,心肌组织和线粒体结构改善,cTnI水平降低,ATP水平升高,心肌线粒体肿胀程度减轻,Nrf2、PGC-1α和Tfam的mRNA表达水平呈剂量依赖性持续升高(<0.05)。
外源性NaHS对脓毒症所致的心肌线粒体损伤具有保护作用。其机制可能在于增强PGC-1α/NRF2通路及线粒体生物合成。