Alleviative Effect Of Soy Isoflavone And Soyasaponin On Physical Fatigue

Object: Along with the social competition becoming intensely and living pressure being greater than ever before, the fatigue has become the universal phenomenon in the society, making the body stay in sub-healthy status. And if its severity above was ignored, it could result in serious illnesses. Soy isoflavone and soyasaponin are the main active compounds in the soy, having various health functions. Some studies indicate that soy isoflavone and soyasaponin have the functions of antioxidation, free radical scavenging activity, and strengthen body constitution. The study will observe the alleviative effects of soy isoflavone and soyasaponin on physical fatigue in mice by animal experiments.Method: According to the basic principles of《Evaluating Rules and Test Methodology of the Function of foods of Health Care》and《Pharmacological experimental Methodology》, 180 ICR adult male mice were divided into 3 big groups randomly by weight, and each big group was divided into 5 small groups, including control group, low dose soy isoflavone group(30 mg/kg·bw), high dose soy isoflavone group(60 mg/kg·bw), low dose soyasaponin group(30 mg/kg·bw) and high dose soyasaponin group(60 mg/kg·bw), 12 mice in each group. During the experimental session, the four test groups were administered soy isoflavone solution or soyasaponin solution every day by mouth, and the normal group was administered the dissolvent of same cubic capacity. All the animals were weighed each 5 days. Quantities of soy isoflavone solution, soyasaponin solution and dissolvent administered orally to rats were changedaccording to their weights. After the mice of the first big group were administered for 30 days, the loading swimming time was tested to observe the time of the mice, then killed them to get the livers. Put the livers into tissue homogenizer to make 20% (w/v) hepatic tissue homogenate with icecold 0.9% NaCL, and determined the activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) in it. After the mice of the second big group were administered for 30 days, high urea model was established to determine the contents of blood urea nitrogen (BUN), hepatic glycogen and muscle glycogen. And after the mice of the third big group were administered for 30 days, high blood lactic acid model was established to determine the contents of blood lactic acid before swimming, after swimming and resting for 20 minutes and the activity of lactate dehydrogenase (LDH), and calculated the area under blood lactic acid curve.The loading swimming time was tested by the loading swimming experiment. The contents of hepatic glycogen, muscle glycogen and BUN and the activity of SOD and LDH were determined by the enzymology method. The content of MDA in liver was determined by TBA colorimetric method. The content of blood lactic acid after swimming was determined by the enzymology method, and calculated the area under blood lactic acid curve.The data were expressed as mean±standard deviation ( x_±s) and analyzed by analysis of variance.Result: There was no difference in weight and the increasing weight before and after the experiment. Compared with control group, the loading swimming times of each dose group were all prolonged, the level of BUN was lower obviously, and the area under blood lactic acid curve and the content of MDA in liver of high dose soy isoflavone group, low dose soyasaponin group and high dose soyasaponin group were decreased obviously. The contents of hepatic glycogen of each dose group and muscle glycogen of high dose soy isoflavone group, lowdose soyasaponin group and high dose soyasaponin group were higher than normal group, and the activities of SOD and LDH enhanced obviously.Compared with low dose soy isoflavone group, the level of BUN of high dose soyasaponin group decreased obviously, and the activities of LDH of high dose soyasaponin group and the activity of SOD of high dose soy isoflavone group were increased obviously. The activity of LDH of high dose soyasaponin was higher than that of low dose soyasaponin obviously. The activity of SOD of high dose soy isoflavone group was higher than that of low dose soy isoflavone group, low dose soyasaponin group and high dose soyasaponin group.Conclusion: The results indicated that soy isoflavone and soyasaponin could release the physical fatigue. Soy isoflavone and soyasaponin could increase the storage of glycogen, enhance the activity of SOD and LDH, and decrease the productions of BUN, blood lactic acid and MDA, in order to release the physical fatigue.The results also indicated that soy isoflavone and soyasaponin of the same dose had the similar effect of releasing the physical fatigue, and need study further.This study could give the proof that soy isoflavone and soyasaponin could reinforce the body constitution and release the physical fatigue directly, and also provide scientific evidence of using of soy isoflavone and soyasaponin in health food and medicine field.