Anti-stress Effects Of RC And Its Possible Mechanisms

Rhodiola（R）and Cordyceps（C）are two kinds of traditional invigoration Chinese medicines, and both of them have the anti-stress effect.It has not been reported the anti-stress effect of combined application of R and C up to now.The purpose of this paper was to optimize the dosage ratio of anti-hypoxic effect of R combined with C（RC）in mice by using orthogonal experimental design,and to evaluate the anti-stress of RC and its possible mechanisms.The results showed that both R（R₁,R₂,R₃ g/kg）and C（C₁,C₂,C₃ g/kg）prolonged the survival time in normobaric hypoxia mice with a dose-dependent manner.R₁ and C₁ had significantly difference compared with control.So,R₁,R₂ and R₃ g/kg（P）and C₁,C₂ and C₃ g/kg（C）were chosed to optimize the dosage ratio of anti-hypoxic effect of RC by using two-factor and three-level orthogonal experimental design.The result showed that optimum proportion of RC was determined.Anti-hypoxic effect of RC was better than that of R and C and showed a time-dependent manner.Moreover,RC prolonged the survival time of mice subjected to NaNO₂,the gasping time of decapitation mice,the swimming time of weight-loaded mice,the survival time of mice in high temperature environment and the death rate of mice in low temperature environment.These results indicated that RC had protective effects on stress caused by hypoxia,megatemperature,hypothermy and fatigue.The possible mechanisms of anti-hypoxic effect of RC were explored in this paper.RC increased the content of Hb and the number of RBC in blood of hypoxia mice,indicated that the increase of transporting oxygen capability is related to the anti-hypoxic effect of RC.In addition, RC increased SOD activity and decreased MDA content in heart and brain of hypoxia mice,and increase GSH content in brain of hypoxia mice.These results indicated that RC could improve hypoxic injury through scavenging flee radical and enhancing the activity of antioxidant system. Moreover,RC decreased LD content and increased LDH activity in blood,enhanced Na⁺-K⁺ ATPase activity in brain,decreased cortical mitochondrial swelling degree and increased cortical mitochondrial membrane potential in hypoxia mice.The results suggested RC could improve energy metabolic disturbance induced by hypoxia,which may be one of the possible mechanisms of anti-hypoxic effect of RC.In conclusion,the paper demonstrated that R combined with C had strong anti-stress activity,and the effect was better than that of R and C used alone.The possible mechanisms may be related to increasing the capability of transporting oxygen,scavenging free radical and enhancing the activity of antioxidant system,and improving energy metabolic disturbance of RC. However,the further mechanisms should be investigated in the futhure.