ABSTRACT
ObjectiveTo observe the effect of polysaccharides from root， stem， leaf and fruit of Schisandra chinensis on exercise endurance in the aging mice induced by D-galactose. MethodMale ICR mice were randomly assigned into six groups： blank control group， model group， root polysaccharide group， stem polysaccharide group， leaf polysaccharide group and fruit polysaccharide group. The mice were administrated with distilled water or root， stem， leaf and fruit polysaccharide （total sugar content of 35 mg·kg-1） by gavage. Thirty minutes after the administration， the blank control group was subcutaneously injected with normal saline， and the other groups with D-galactose （300 mg·kg-1）， once daily for 6 weeks. The anti-fatigue effects were evaluated by rotarod test， forelimb grip strength test， and weight-loaded swimming test. The fatigue and oxidation indicators such as blood urea nitrogen （BUN）， serum lactic acid （LD）， lactic dehydrogenase （LDH）， creatine kinase （CK）， superoxide dismutase （SOD）， malondialdehyde （MDA）， glutathione peroxidase （GSH-Px）， and reactive oxygen species （ROS） were measured by chemical colorimetry. The protein levels of pro-apoptotic protein B cell lymphoma-2 （Bcl-2）-associated X protein （Bax）， anti-apoptotic Bcl-2 and cleaved cysteinyl aspartate-specific protease-3 （cleaved Caspase-3） in mouse skeletal muscle were detected by Western blot. ResultIn the rotarod test， the time on rod was shorter in the model group than in the blank control group （P<0.01） and the root， stem and fruit polysaccharide groups （P<0.01）. In the forelimb grip strength test， the forelimb grip strength in the model group was lower than that in the blank control group （P<0.01） and the root， stem， leaf and fruit polysaccharide groups （P<0.01）. In the weight-loaded swimming test， the weight-loaded swimming time in the model group was shorter than that in the blank control group （P<0.01） and the root， stem， leaf and fruit polysaccharide groups （P<0.01）. Compared with those in the blank control group， the BUN， LD， LDH and CK levels significantly increased in the model group （P<0.05， P<0.01）. The increases in BUN and LDH levels were decreased by the root， stem and fruit polysaccharides （P<0.05， P<0.01） and those in LD and CK by the root， stem， leaf and fruit polysaccharides （P<0.05， P<0.01）. Compared with the blank control group， the model group showed decreased SOD and GSH-Px activities （P<0.01） and increased MDA and ROS content （P<0.01）. Compared with the model group， the root， stem， and fruit polysaccharide increased the SOD activity （P<0.05， P<0.01） and decreased ROS content （P<0.01）. The root and stem polysaccharides decreased the MDA content （P<0.01） and increased the GSH-Px activity （P<0.05， P<0.01）. Compared with the blank control group， the model group showed up-regulated protein levels of Bax and cleaved Caspase-3 and down-regulated protein level of Bcl-2 （P<0.01）. Compared with the model group， the root， and stem polysaccharides down-regulated the protein levels of cleaved Caspase-3 （P<0.05） and up-regulated protein level of Bcl-2 （P<0.01）. ConclusionThe polysaccharides from the root， stem， leaf， and fruit of S. chinensis have anti-fatigue effect in D-galactose-induced aging mice. The polysaccharides may exert such effect by improving the antioxidant capacity and inhibiting the apoptosis of skeletal muscle cells.