脾气虚大鼠胃黏膜细胞线粒体自噬相关蛋白表达的研究

Expressions of Mitophagy-Related Proteins in Gastric Mucosal Cells of Rats in Spleen Qi Deficiency

目的通过检测PTEN诱导激酶1(PTEN-induced putative kinase protein 1,PINK1)-Parkin通路及自噬相关蛋白表达,探讨脾气虚胃黏膜细胞线粒体损伤的可能机制。方法 16只雄性SD大鼠随机分为正常组和脾气虚证模型组(模型组),每组8只;透射电镜观察胃黏膜细胞线粒体形态,JC-1法测量其膜电位(ΔΨm);比色法测定其ATP含量和呼吸链复合物(respiratory chain complex,RCC)Ⅰ-Ⅳ活性;Western blot法检测其RCCV、PINK1、Parkin、微管相关蛋白1轻链3(microtubule-associated protein light chain 3,LC3)-Ⅰ和Ⅱ及p62等表达。结果与正常组比较,模型组胃黏膜细胞的线粒体嵴减少,ΔΨm和ATP水平下降,RCCⅠ和Ⅳ活性降低,RCCV、PINK1、Parkin和LC3-Ⅱ表达下降,但LC3-Ⅰ和p62表达上升。结论脾气虚胃黏膜细胞线粒体结构和功能损伤与PINK1-Parkin通路抑制所导致的线粒体自噬水平低下有关。

Objective To explore the possible mechanism of mitochondrial impairment of gastric mucosal cells(GCEs)in spleen qi deficiency by detecting PTEN induced putative kinase 1(PINK1)-Parkin pathway and autophagy-related protein expressions. Methods A total of 16 male SD rats were randomly divided into normal group and spleen qi deficiency(model) group with 8 in each group. Transmission electron microscopy was used to observe the mitochondrial morphology in GMCs, and JC-1 method was used to measure their membrane potentials(ΔΨm). Colorimetry was chosen to detect their respiratory chain complex(RCC) Ⅰ-Ⅳ activities. The expressions of RCCV, PINK1, Parkin, microtubuleassociated protein 1 light chain 3(LC3)-Ⅰ/Ⅱ and p62 was detected by Western blot. Results Compared with those in the normal group, the model group had reduced mitochondrial cristae, decreased ΔΨm and ATP levels, decreased activities of RCCⅠ and Ⅳ, declined expressions of RCCV, PINK1, Parkin and LC3-Ⅱ, but increased expression of LC3-Ⅰ and p62. Conclusion Impairment of GMCs’ mitochondria in spleen qi deficiency might be caused by the mitophagy reduction due to PINK1-Parkin pathway inhibition.