Effects Of Taurine On Pancreatic Stem Cells In Diabetic Rats

Diabetes,a common metabolic disease worldwide,has a significant impact on the quality of life of patients.Regular drugs and insulin injections are not enough to cure diabetes.In recent years,the related research of stem cells has been gradually developed,which is expected to cure diabetes and its complications fundamentally,so it has become a hot research in the treatment of diabetes.Our previous study showed that taurine could inhibit the increase of blood glucose and protect islet β cells in diabetic model rats.It was speculated that taurine could promote the increase of pancreatic β cells by promoting the proliferation and differentiation of pancreatic stem cells.In this experiment,100 SPF grade SD male rats were selected and 50 rats were injected intraperitoneally with 50 mg/kg streptozocin(STZ)to establish the diabetic model.The blood glucose levels of the rats injected with STZ were measured three days and one week later.The diabetic model was successfully established when the random blood glucose levels were higher than 16.7 mmol/L.Then the experimental animals were divided into four groups: blank control group(C),taurine control group(T),diabetic model group(M)and taurine intervention group(T+M).The rats were kept for 12 weeks and their blood glucose and body weight were measured every week.The levels of HbA1 c,Insulin,Glucagon and GLP-1 in blood of rats were measured at the 4th,8th,12 th week after taurine intervention in each group.The expression of BrdU and Insulin positive cells was detected by tissue immunofluorescence staining,and the proliferation rate of islet β cells and CK19 positive cells were detected by tissue immunofluorescence double staining.Western-blot technique was used to detect the relative expression of Insulin,CK19,Nestin,Pdx1 and Sox9 protein in pancreas,to explore the regulatory effect of taurine on pancreatic stem cells in diabetic rats induced by STZ and its possible mechanism.The results showed that continuous taurine supplementation could significantly decrease the blood glucose and reduce the weight difference between the diabetic rats and the normal rats after the establishment of SD rats diabetic model.At the 4th,8th,12 th week,the blood HbA1 c content in the taurine intervention group was significantly lower than that in the model group(P<0.05),and the difference in the 4th week was extremely significant(P<0.01).At the 4th week of the experiment,there was no significant difference in serum Insulin between the four groups(P>0.05);The level of serum Insulin in the taurine intervention group was significantly higher than that in the model group at the 8th week and the 12 th week(P<0.05).The level of serum Glucagon in the group was significantly lower than that in the model group at the 12 th week(P<0.05),and the level of GLP-1 in the taurine intervention group was significantly higher than that in the model group(P<0.05).The results of immunofluorescence staining showed that the positive rate of BrdU in pancreatic tissue of taurine intervention group was extremely significant higher than that of model group(P<0.01).The positive rate of Insulin in pancreatic tissue of taurine intervention group was significant higher than that of model group(P<0.05).The results of immuno-fluorescence double staining test showed that the proliferation rate of islet β cells in taurine intervention group was extremely significant higher than that in model group at the 8th week(P<0.01);At the 12 th week,the proliferation rate of islet β cells in taurine group was significantly higher than that in model group(P<0.05).There was no significant difference in proliferative rate of CK19 positive cells among four groups at all time points(P>0.05).The results of Western-blot test showed that taurine could significantly up-regulate the relative expression of Insulin,Nestin,Pdx1,Sox9 protein in pancreatic tissue(P<0.05),but had little effect on the regulation of CK19 protein(P>0.05).The results showed that taurine could up-regulate the expression of pancreatic stem cell markers,promote the proliferation and differentiation of islet β,and improve the increase of blood glucose,weight loss ahd other diabetes symptoms in diabetic rats induced by STZ.