Effect And Action Mechanism Of Shi-liang Tea,a Major Anhua Deep-black Tea, On Blood Glucose In Db/Db Diabetic Mice

Objective:The aims of the study were to investigate hypoglycemic effect and mechanism of Shi-Liang tea, the major AnHua deep-black tea in Hunan province.Methods:We detected the BKS.Cg-m+/+Leprdb/J (db/db) type2diabetes mellitus mice’s Fasting blood-glucose (FBG) level. According to the FBG level and the body weight, the mices, whose FBG level are bigger than11.1mol/L, were random divided into5groups (n=6:The model group, the positive control group(Rosiglitszone,RSG5mg/kg), the three different dose of Shi-Liang tea extract (100mg/kg,200mg/kg and400mg/kg). The BKS.Cg-m wild-type mice were simultaneously labeled blank group. The administration group were gavaged0.2ml/lOg drugs once daily for28days. The blank and model group were gavaged0.2ml/10g double distilled water once daily for28days. The Fasting serum insulin(FINS) level were detected in the first and twenty-eighth day. The body weight were measured once per week.The mices were gavaged with medicine after4hours with no food but water in the7th day,14th day and21st day. After taking medicine for one hour, FBG level were detected.The mices were gavaged with medicine after4hours with no food but water in the28th day. After giving medicine one hour, the blood sugar were detected as the before taking glucose value. Immediately administer Glucose(GLU2.5g/kg), the blood sugar and the insulin level were detected after giving medicine one hour, two hours and three hours.Results:(1)The Shi-Liang tea extract effect on the weight of rats that suffesr diabete:In the entire experimental, the weight of the model group is obviously higher than that of the normal group in the same week of age (P<0.01) During the period of giving medicine, the extract of Shi-Liang tea(200/400mg/kg) group and the RSG (5mg/kg) group begun to show a trend of inhibiting the increase of diabetes mice’weight from gavaged medicine21th day, and obvious difference occured compared with the model group from gavaged medicine28th day (P<0.01).(2) The Shi-Liang tea extract effect on the FBG of rats that suffesr diabete:In the entire experimental, the FBG of the model group is obviously higher than that of the normal group in the same week of age (P<0.01). During the period of giving medicine, the extract of Shi-Liang tea(200/400mg/kg) group group begun to show a trend of inhibiting the increase of diabetes mice’FBG from gavaged medicine21th day, and obvious difference occured compared with the model group from gavaged medicine28th day (P<0.01). At the same time, RSG(5mg/kg) group could remarkably decrease the level of FBG of db/db diabetic rats from the14th day to28th day after giving medicine.(3) The Shi-Liang tea extract effect on the FINS of rats that suffesr diabete:In the entire experimental, the FINS of the model group is obviously higher than that of the normal group in the same week of age (P<0.01). Compared with the normal group, the Shi-Liang tea extract (400mg/kg) could obvious reduce the FINS level (P<0.01) from the28th day after giving medicine. Compared with the normal group RSG (5mg/kg) group could remarkably decrease the FINS level of db/db diabetic mices from the28th day after giving medicine(P<0.01).(4) The Shi-Liang tea extract effect on the the Oral Glucose tolerans test (OGTT) of rats that suffesr diabete:Compared with the normal group and the control group,the Shi-Liang tea extract(400mg/kg) and RSG (5mg/kg) group could obviously inhibit the increase of blood-glucose level in the administration glucose of diabetic mices for1to3hours(P<0.01).(5) The Shi-Liang tea extract effect on the insulin level in the Oral Glucose tolerans test (OGTT) of rats that suffesr diabete:The increase in serum insulin levels in diabetic mice,which were GLU,was not obvious and the peak was at2h later. However, the Shi-Liang tea (400mg/kg) extract and RSG5mg/kg could greatly increase the insulin level of diabetic mice after gaven glucose, and the peak occured after1hour (compared with the normal group and the control group, P<0.01)Conclusions::(1) The Shi-Liang tea extract had hypoglycemic effection and its effection maybe relate to increasing insulin release.(2)The hypoglycemic effection of Shi-Liang tea extract on type2diabetes mellitus mice reached peak one hour later and showed time-dose dependent relationship.