Study On Anti-fatigue Effect And Mechanism Of Polygonatum Polysaccharide

Polygonatum is a liliaceae plant with edible and medicinal value.Its rhizome can be used as medicine,which has a variety of pharmacological effects such as spleen invigorating,vital energy benefiting and kidney tonifying.Polysaccharide is an important active component of Polygonatum with an extensive research.Fatigue affects people's life and work,and relieving fatigue is crucial to maintain body health.But how to better prevent fatigue and the underlying molecular mechanisms involved in the development of fatigue have not been fully understood.In the preliminary work,a homogeneous polysaccharide component PCP1 from Polygonatum,was obtained by optimizing the extraction process.Based on this,the fatigue model was constructed by using weight-bearing swimming in mice,and the anti-fatigue activity and related regulation mechanism of PCP1 were studied.The results of the study were as follows:Based on the single-factor test,response surface method was used to optimize the extraction process of Polygonatum polysaccharide,and the optimal conditions were obtained: solid-liquid ratio of 1:25,extraction temperature of 85?,extraction time of 2h,and the best yield was 13.36%.The obtained polysaccharides were further separated and purified by Sevage method and DE-52 cellulose anion exchange column to get four polysaccharides of different components,namely PCP1,PCPS1,PCPS2 and PCPS3.The PCP1 was given to mice at different doses for 28 days to explore the anti-fatigue effects of PCP1 and its possible mechanism.In addition,the anti-fatigue effects of PCP1 at different dosages on mice of different months were studied.The results showed that PCP1 had anti-fatigue activities as supported by exhaustive swimming experiments in mice,serum biochemical indicators and q PCR experiments.Compared with the control group,the weight of mice in the gavage polysaccharide group was lower,and swimming time increased significantly.The anti-fatigue activities of PCP1 mainly included the following three points:(1)Increased the storage of energy substances(hepatic glycogen,muscle glycogen,ATP)in mice by regulating the intake and metabolism of glucose and lipids,and decreased the accumulation of metabolites(lactic acid,urea nitrogen),so as to decrease the damage to cells and organs,thus delaying the fatigue caused by energy exhaustion;(2)Enhanced the cross-sectional area of muscle fibers in mice to improve muscle strength,thereby playing the role of anti-fatigue.(3)Improved the activity of antioxidant enzymes and reduced the activity of oxidase,thus decreasing the harm of lipid peroxidation to human body.Furthermore,the anti-fatigue mechanisms of Polygonatum polysaccharides were explored.Polygonatum polysaccharides promoted the m RNA expression of transcription factors(BMP-2,Smad1,RUNX2)to induce osteoblasts to synthesize and secrete osteocalcin,and elevated the m RNA levels of downstream genes(Cd36,Fatp1,GLUT4,Cpt1b),thus accelerating the uptake and metabolism of glucose and lipids,reducing the fatigue caused by energy exhaustion.The above experimental results showed that PCP1 mainly increased the intake and metabolism of glucose and lipids,reduced the accumulation of lactic acid and urea nitrogen,and decreased the damage of oxidative stress to the body,thereby delaying the occurrence of fatigue.This study might provide a new theoretical basis for the research of anti-fatigue and a new possibility for the development and utilization of Polygonatum.