Departments of Histology and Cell Biology, Faculty of Medicine, Mansoura University, Mansoura, Egypt.
J Mol Histol. 2011 Jun;42(3):217-25. doi: 10.1007/s10735-011-9326-6. Epub 2011 Apr 21.
Low muscle strength is observed during the peri-and postmenopausal periods, when the secretion of ovarian hormones is drastically reduced. It is also a predictive of adverse health events as well as incident mobility limitation and disability. The objective of the present study is to study the biochemical and the histological changes in the skeletal muscle of premature menopause-induced rats and the possible protective role of L-carnitine. Ovariectomized (OVX) rats were gavaged with L-carnitine (100 mg/kg) daily for 60 days starting from the second post-operative day. Serum levels of estradiol and markers of skeletal muscle damage (creatine kinase and lactic dehydrogenase activities) were determined. Light and electron microscopic study of the quadriceps femoris muscle (QFM) specimens were done. OVX rats showed significant decrease in the serum estradiol level with significant increase the markers for skeletal muscle damage. Histopathological examination of the QFM showed degenerated myofibers, apoptotic changes and compensatory hypertrophy. Degenerated mitochondria, multiple lysosomes and lipid droplets among the damaged myofibrils were also noticed. L-carnitine administration to the OVX rats resulted in non-significant change in the serum estradiol level with significant attenuation of skeletal muscle damage either biochemically or histopathologically. In conclusion, L-carnitine administration recovered muscle degeneration after ovariectomy. This finding suggested that L-carnitine could be recommended in the management of post-menopausal myopathy.
绝经前期和绝经后期卵巢激素分泌急剧减少，导致肌肉力量减弱。肌肉力量减弱也是不良健康事件以及活动受限和残疾的预测因素。本研究旨在研究过早绝经诱导的大鼠骨骼肌的生化和组织学变化，以及左旋肉碱的可能保护作用。从术后第 2 天开始，对卵巢切除术（OVX）大鼠每天灌胃左旋肉碱（100mg/kg），持续 60 天。测定血清雌二醇水平和骨骼肌损伤标志物（肌酸激酶和乳酸脱氢酶活性）。对股四头肌（QFM）标本进行光镜和电镜研究。OVX 大鼠血清雌二醇水平显著降低，骨骼肌损伤标志物显著增加。QFM 的组织病理学检查显示退行性肌纤维、凋亡变化和代偿性肥大。受损肌纤维之间还注意到退化的线粒体、多个溶酶体和脂滴。左旋肉碱给药给 OVX 大鼠后，血清雌二醇水平无显著变化，但在生化或组织病理学上均显著减轻了骨骼肌损伤。总之，左旋肉碱给药可恢复卵巢切除术后的肌肉退化。这一发现表明，左旋肉碱可推荐用于绝经后肌病的治疗。
