Effect of Suanzaoren Tang on Mitochondrial Damage and Apoptosis in Hypothalamus of Elderly Rats with Chronic Rapid Eye Movement Sleep Deprivation / 中国实验方剂学杂志

ABSTRACT

Objective:To investigate the effect of Suanzaoren Tang on mitochondria-mediated neuronal apoptosis. Method:Fifty male Wistar rats were randomly divided into the control group， model group， estazolam group （0.18 mg·kg^-1·d^-1）， and low- （6.48 g·kg^-1·d^-1） and high-dose （12.96 g·kg^-1·d^-1） Suanzaoren Tang groups. Rats in all groups except for the control group received subcutaneous injection of <italic>D</italic>-galactose and then were deprived of sleep using the multiple platform method after the last administration. Following successful modeling， the rats in each group were treated with intragastric administration of the corresponding drugs for seven consecutive days. The morphology of mitochondria in hypothalamus was observed under a transmission electron microscope. The activities of Na⁺-K⁺-ATPase and Ca²⁺-Mg²⁺-ATPase in hypothalamus were detected by spectrophotometry. Western blotting was conducted to determine the protein expression levels of cytochrome C （Cyt C）， B cell lymphoma-2 （Bcl-2）， Bcl-2 associated X protein （Bax） and cysteinyl aspartate-specific protease-3 （Caspase-3） in hypothalamus. Result:In the control group， there was no obvious pathological change in mitochondria， which were moderate in size and oval or spindle in shape， with the cristae arranged orderly. Compared with the control group， the model group exhibited abnormal mitochondrial morphology， manifested as obvious swelling， vacuolation， myelin figures， and cristae rupture and reduction. The comparison with the model group revealed that both the estazolam group and high-dose Suanzaoren Tang group alleviated the mitochondrial damage and reduced the vacuolation and swelling. Only some cristae rupture was present. The improvements were more obvious in the high-dose Suanzaoren Tang group. Compared with the control group， the activities of Na⁺-K⁺-ATPase and Ca²⁺-Mg²⁺-ATPase and the Bcl-2 protein expression in the model group were significantly decreased （<italic>P<</italic>0.01）， whereas the protein expression levels of Cyt C， Bax， and Caspase-3 were significantly increased （<italic>P</italic><0.01）. Compared with the model group， the activities of Na⁺-K⁺-ATPase and Ca²⁺-Mg²⁺-ATPase and the Bcl-2 protein expression in the estazolam group and the high-dose Suanzaoren Tang group were significantly elevated （<italic>P<</italic>0.01）， while the protein expression levels of Cyt C， Bax， and Caspase-3 were significantly lowered （<italic>P<</italic>0.05， <italic>P<</italic>0.01）. The activity of Na⁺-K⁺-ATPase and the Bcl-2 protein expression in the low-dose Suanzaoren Tang group were increased significantly （<italic>P<</italic>0.01）， but the Bax protein expression was down-regulated （<italic>P<</italic>0.05）. Conclusion:Suanzaoren Tang is able to improve the mitochondrial function of hypothalamic nerve cells and inhibit their apoptosis.