Chemical composition of three polysaccharides from Gynostemma pentaphyllum and their antioxidant activity in skeletal muscle of exercised mice.
OBJECTIVE
To investigate the effects of polysaccharide from Gynostemma pentaphyllum on antioxidant activity in skeletal muscle of mice exercised to exhaustion.


METHODS
Three polysaccharide fractions were obtained from G. pentaphyllum polysaccharide (GPP) and termed GPP1-a, GPP2-b, and GPP3-a. Gas chromatography (GC) and infrared spectrum of the polysaccharides were determined. The fractions were orally administrated to mice once daily for 1 wk. The exercise time to exhaustion was assessed using a forced swim test of mice after a week. The glucose, creatine phosphokinase, and lactic dehydrogenase in serum; the activity of superoxide dismutase and glutathione peroxidase; and the levels of malondialdehyde (MDA) and glycogen in muscle were determined.


RESULTS
The results of GC demonstrated that GPP1-a, GPP2-b, and GPP3-a were composed of different monosaccharides with distinct molar ratios. Infrared spectrum showed that the main typicals of GPP1-a and GPP2-b were β-configuration and the main typical of GPP3-a was α-configuration. Among the 3 fractions of GPP, GPP1-a administration significantly prolonged exercise time to exhaustion of mice, increased glycogen level and some of antioxidant enzyme activities, and decreased MDA level in muscle.


CONCLUSIONS
The mechanism by which GPP1-a prolonged exercise time to exhaustion in mice may be associated with scavenging reactive oxygen species excessively produced and further increasing glycogen levels in skeletal muscle.
School of Exercise, Shaanxi Normal University, Xi'an, China.
Aiping
A
Chi
Liang
L
Tang
Jing
J
Zhang
Kunru
K
Zhang
D000818:Animals; D021461:Animals, Outbred Strains; D000975:Antioxidants / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use*; D002236:Carbohydrate Conformation; D003402:Creatine Kinase / Q000037:antagonists & inhibitors / Q000097:blood; D019587:Dietary Supplements; D019448:Ethnobotany; D005221:Fatigue / Q000097:blood / Q000378:metabolism / Q000517:prevention & control*; D006003:Glycogen / Q000378:metabolism; D029774:Gynostemma / Q000737:chemistry*; D045022:Lactate Dehydrogenases / Q000037:antagonists & inhibitors / Q000097:blood; D015227:Lipid Peroxidation; D008297:Male; D008516:Medicine, Chinese Traditional; D051379:Mice; D018482:Muscle, Skeletal / Q000378:metabolism*; D058573:Performance-Enhancing Substances / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use; D005082:Physical Exertion; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use*; D011134:Polysaccharides / Q000008:administration & dosage / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use*; D011897:Random Allocation; D013550:Swimming
D000975:Antioxidants; D058573:Performance-Enhancing Substances; D010936:Plant Extracts; D011134:Polysaccharides; D006003:Glycogen; D045022:Lactate Dehydrogenases; D003402:Creatine Kinase