Autophagy is a lysosome-mediated degradation process for non-essential or damaged cellular constituents, playing an important homeostatic role in cell survival, differentiation and development to maintain homeostasis. Autophagy is involved in tumors as well as neurodegenerative, cardiovascular and cerebrovascular diseases. Recently, active compounds from traditional Chinese medicine (TCM) have been found to modulate the levels of autophagy in tumor cells, nerve cells, myocardial cells and endothelial cells. Ischemic stroke is a major cause of neurological disability and places a heavy burden on family and society. Regaining function can significantly reduce dependence and improve the quality of life of stroke survivors. In healthy cells, autophagy plays a key role in adapting to nutritional deprivation and eliminating aggregated proteins, however inappropriate activation of autophagy may lead to cell death in cerebral ischemia. This paper reviews the process and the molecular basis of autophagy, as well as its roles in cerebral ischemia and the roles of TCM in modulating its activity.
Xiao-ping HuangHuang DingJin-dong LuYing-hong TangBing-xiang DengChang-qing Deng
Objective: To explore the effects and molecular mechanisms of the combination between total Astragalus extract (TAE) and total Panax notoginseng saponins (TPNS) against cerebral ischemia- reperfusion injury. Methods: C57BL/6 mice were randomly divided into sham-operated group, model group, TAE (110 mg/kg) group, TPNS (115 mg/kg) group, TAE-TPNS combination group and Edaravone (4 mg/kg) group, treated for 4 days, then, cerebral ischemia-repeffusion injury was established by bilateral common carotid artery (CCA) ligation for 20 min followed by reperfusion for 1 and 24 h. Results: TPNS could increase adenosine triphosphate (ATP) level, TAE and TAE-TPNS combination increased ATP, adenosine diphosphate (ADP) contents and Na+-K+-ATPase activity, and the effects of TAE-TPNS combination were stronger than those of TAE or TPNS alone after reperfusion for 1 h. After reperfusion for 24 h, TAE, TPNS and TAE-TPNS combination significantly increased neurocyte survival rate and decreased the apoptosis rate as well as down-regulated the expression of phosphorylated c-June N-terminal kinasel/2 (p-JNK1/2), cytochrome C (Cyt C), cysteine aspartic acid-specific protease (Caspase)-9 and Caspase-3. Furthermore, the effects in TAE-TPNS combination were better than those in TAE or TPNS alone. Conclusion: The combination of TAE 110 mg/kg and TPNS 115 mg/kg could strengthen protective effects on cerebral ischemia injury, the mechanism underlying might be related to improving jointly the early energy metabolism, and relieving the delayed apoptosis via inhibiting the mitochondrial apoptosis pathway of JNK signal transduction.