Effects Of Estrogen On Expression And Function Of Glucose Transporters In Duodenal Mucosa

Objective:At present,obesity has become a global problem.According to surveys,the prevalence of obesity in menopausal women has greatly increased,and the characteristic of menopausal women is the decline in estrogen levels.It is well known that the absorption of glucose is closely related to obesity,and reports have shown that estrogen plays an important role in the absorption of glucose in the duodenum,but the mechanism of action is still unclear.Therefore,this project aims to provide a theoretical basis for the clinical application of estrogen drugs by studying the regulation mechanism of estrogen on the expression and functional activity of the duodenal mucosal glucose transporter.Methods:1.Establish an ovariectomized mouse model.2.Verify whether the ovariectomized mouse model is successfully established:Radioimmunoassay is used to detect the serum estradiol level of the modeled mice.3.From the second day after the ovariectomized operation,weigh and record the body weight of the modeled mice at a fixed time.4.Anatomy modeling mice,observe the distribution of fat in the two groups of mice.5.The oral glucose tolerance test(OGTT)was performed after the weight of the modeled mice stabilized(about 2 weeks).6.Using the Ussing chamber technology to detect and observe the short-circuit current difference(ΔIsc)caused by the duodenal glucose absorption of the modeling mice,and the immunohistochemical method to detect the SGLT1 and GLUT2 in the duodenum tissue of the modeling mice The expression of the situation.7.Using immunohistochemistry and Western-blot methods to detect the expression of ER-α and ER-β in the duodenal tissue of modeled mice.8.Western-blot method was used to detect the protein expression of SGLT1 and GLUT2 in SCBN(dog’s duodenum)cells stimulated by estrogen,and the proteins of SGLT1 and GLUT2 in SCBN cells that were stimulated by estrogen to silence ER-α and ER-β Express the situation.9.The Western-blot method was used to detect the protein expression of P-PKC after estrogen stimulated SCBN cells,and the protein expression of SGLT1 and GLUT2 after PKC agonist PMA and inhibitor G?6976 stimulated dog duodenal(SCBN)cells.10.The Western-blot method was used to detect the protein expression of SGLT1 and GLUT2 in SCBN cells after PMA and G?6976 stimulated silencing of ER-α and ER-β.Results:1.Compared with the sham operation group,it can be seen that there is a lack of pink mulberry-like ovarian tissue in the abdominal cavity of the ovariectomized mice.2.Compared with the sham operation group,the serum estradiol level of the ovariectomized mice was lower(P<0.05).3.Compared with the sham operation group,the mice in the ovariectomized group gained weight(P<0.05).4.Compared with the sham operation group,the abdomen fat of the ovariectomized mice was significantly increased,mainly white fat.5.Oral glucose tolerance test(OGTT)showed that the blood glucose level of ovariectomized mice was higher than that in the sham operation group(P<0.05).6.Compared with the sham operation group,the change of ΔIsc caused by the intestinal mucosal glucose absorption of the ovariectomized mice was reduced(P<0.05);Compared with the sham operation group,the SGLT1 and GLUT2 in the duodenum of the ovariectomized mice The expression decreased(P<0.05).7.Compared with the sham operation group,the expressions of ER-α and ER-β in the duodenum of the ovariectomized mice were reduced(P<0.05).8.Compared with the control group,the protein expression of SGLT1 and GLUT2 increased after estrogen stimulated SCBN cells(P < 0.05);Compared with the control group,after estrogen stimulated SCBN cells that silenced ER-α,the protein expression of SGLT1 and GLUT2 had no significant difference(P > 0.05).After estrogen stimulated SCBN cells that silenced ER-β,the protein expression of SGLT1 and GLUT2 was significantly increased(P<0.05).9.Compared with the control group,after estrogen stimulated SCBN cells,the protein expression of P-PKC was significantly reduced(P<0.05);Compared with the control group,the protein expression of SGLT1 and GLUT2 decreased after PMA stimulated SCBN cells(P < 0.05);Compared with the control group,after PMA stimulated SCBN cells that silenced ER-α,the protein expression of SGLT1 and GLUT2 decreased(P<0.05);Compared with the control group,after PMA stimulated the SCBN cells that silenced ER-β,the protein expression of SGLT1 and GLUT2 decreased(P<0.05);Compared with the control group,the protein expression of SGLT1 and GLUT2 increased after G?6976stimulated SCBN cells(P < 0.05);Compared with the control group,after G?6976stimulated SCBN cells that silenced ER-α,the protein expression of SGLT1 and GLUT2 had no significant difference(P>0.05);Compared with the control group,after G?6976stimulated the SCBN cells that silenced ER-β,the protein expression of SGLT1 and GLUT2 increased(P<0.05);Conclusion:When estrogen is absent,the cause of the increase in blood sugar in mice is not the increase in the absorption of glucose by the duodenum.On the contrary,the absorption of glucose by the duodenum is reduced,and estrogen regulates the duodenal sugar transporter.Absorption is achieved through the PKC pathway and has a reverse regulatory effect.