【摘要】 目的:探讨大鼠偏侧咀嚼过程中大鼠咬肌过氧化物酶增殖激活受体γ协同刺激因子-1α(PGC-1α)、葡萄糖转运蛋白4(GLUT4)及线粒体损伤程度的表达变化规律,进一步研究偏侧咀嚼致咬肌功能紊乱的机制。方法:取8w龄健康雄性Wistar大鼠咬肌,用实时荧光定量PCR(real-time,PCR)法检测咬肌中PGC-1αmRNA及GLUT4mRNA的相对表达量;电镜观察线粒体形态和数目的变化并计算线粒体损伤指数。结果:拔牙侧与非拔牙侧PGC-1αmRNA表达量第4w最高,第8w最低;除第6w周组外,拔牙侧PGC-1αmRNA表达量明显高于非拔牙侧及对照组(P<0.01)。拔牙侧与非拔牙侧线粒体损伤评分第8w最高,4w最低;除第8w组外,拔牙侧线粒体损伤评分明显低于非拔牙侧及对照组(P<0.01)。拔牙侧与非拔牙侧GLUT4 mRNA的表达量第4w时最高,第8w时最低;2w组与4w组拔牙侧GLUT4mRNA的相对表达量明显高于对照组(P<0.01)。GLUT4与PGC-1α呈正线性相关(r值为0.8650,P<0.01);PGC-1α与线粒体损伤指数无明显的相关性。结论:偏侧咀嚼可引起咬肌线粒体损伤;PGC-1α可通过调控GLUT4的表达而调节咀嚼肌细胞的能量代谢,是偏侧咀嚼致咬肌功能紊乱的发生机制之一。更多还原

【Abstract】 Objective: To investigate the changes of expression of peroxisome proliferator-activated receptor-γ coactivator-1α(PGC-1α), glucose transporter 4(GLUT4) and the degree of mitochondrial damage, in order to further investigate the mechanism in masseter muscle dysfunction induced by hemimastication. Method: The relative expression of the PGC-1αmRNA and GLUT4mRNA in the masseter muscle were detected using real time PCR. Mitochondrial morphology and changes in the number were observed using electron microscopy, followed by calculation of mitochondrial damage index.Results: 1) Expression levels of PGC-1αmRNA in both extraction and non-extraction side reached the maximum at four weeks and minimum at eight weeks; Except for at the sixth week, the PGC-1αmRNA expression of extraction side was significantly higher than the non-extraction side and the control group(P <0.01). 2) The mitochondrial injury score of both theextraction and the non-extraction side reached the maximum at 8 weeks and minimum at 4 weeks; Except for at the 8th week, mitochondrial injury score of the extraction side was significantly lower than the non-extraction side and the control group(P <0.01). 3) Expression levels of GLUT4mRNA in the extraction and the non-extraction side reached the maximum at 4 weeks and minimum at 8 weeks; While the relative expression levels of GLUT4mRNA of the extraction side at 2 weeks and 4 weeks were significantly higher than the control group(P <0.01). 4) GLUT4 and PGC-1α were showed to have a positive linear correlation(r = 0.8650, P <0.01); while there was no obvious correlation between PGC-1α and mitochondrial damage. Conclusion: Hemimastication could cause mitochondrial damage; PGC-1α could regulate the energy metabolism of muscle cells through regulate the expression of GLUT4, which might be one of the mechanisms that cause masseter dysfunction induced by hemimastication.更多还原