摘要
目的:构建1型糖尿病(type 1 diabetes mellitus,T1DM)小鼠反复低血糖(recurrent hypoglycaemia,RH)模型,并探讨低血糖时其胰高血糖素样肽1(glucagon-like peptide-1,GLP-1)在肠道的表达及意义。方法:以链脲佐菌素诱导C57BL/6J小鼠,形成T1DM,在糖尿病第15天腹腔注射短效胰岛素,每3 d注射1次,连续5次降至低血糖,以构建T1DM-RH模型。建模期间记录小鼠体重、血糖水平及活动状态;ELISA检测模型鼠第5次降糖持续60min后的血浆肾上腺素、胰高血糖素(glucagon,GCG)、生长抑素(somatostatin,SST)和GLP-1水平;免疫荧光检测模型鼠肠GLP-1和胰岛α、δ细胞激素的分泌变化;Western blot检测回肠和结肠的GLP-1及其受体GLP-1R、激素原转化酶1/3(prohormone convertases 1/3,PC1/3)蛋白的表达。结果:血糖、体重符合T1DM鼠标准。RH组连续降糖5次,每次血糖均降至(3.3±0.5) mmol/L,且持续时间>60 min,加之其血浆肾上腺素、血浆GCG水平及RH小鼠降糖期间行为改变,符合糖尿病小鼠RH和低血糖反调节障碍的建模标准。ELISA显示,与T1DM组相比,RH组血浆肾上腺素和GCG水平均下降(P<0.01),血浆SST和活性GLP-1水平显著升高(P<0.01);免疫荧光显示,与T1DM组相比,RH组肠GLP-1表达升高,胰岛SST分泌增多(P<0.01),GCG分泌减少(P<0.01);Western blot显示,与T1DM组相比,RH组肠活性GLP-1和GLP-1R明显升高(P<0.01)。结论:TIDM-RH小鼠肠GLP-1表达升高,与低血糖反调节障碍的形成或加重密切相关。
AIM:To establish a model of recurrent hypoglycemia(RH)in mice with type 1 diabetes mellitus(T1DM)and to investigate the expression and effects of glucagon-like peptide-1(GLP-1)in the intestines of the model mice.METHODS:The T1DM model was established by induction with streptozotocin.Starting from the 15th day of T1DM,the mice in RH group were injected intraperitoneally with short-acting insulin,experiencing 1 episode of hyperin-sulinemic hypoglycemia every 3 days over 5 episodes,to establish the RH model in T1DM mice.Body weight,blood glu-cose,and activity status of the mice were recorded.Enzyme-linked immunosorbent assay(ELISA)was used to measure plasma adrenaline,glucagon(GCG),GLP-1,and somatostatin(SST)levels after the fifth episode of hypoglycemia for 60 min.Immunofluorescence staining was utilized to detect the expression of intestinal GLP-1 and hormone secretions from pancreaticαandδcells in each group.Western blot was employed to detect protein expressions of GLP-1,GLP-1 receptor(GLP-1R),and prohormone convertase 1/3(PC1/3)in the intestine.RESULTS:Blood glucose and body weight met the standards for T1DM mice.During the 5 episodes of hypoglycemia,blood glucose levels in the RH group dropped to(3.3±0.5)mmol/L for more than 60 min during each episode of hypoglycemia,along with levels of plasma adrenaline and gluca-gon and the behavioral changes of RH mice during hypoglycemia,which met the modeling criteria of RH and impaired hy-poglycemic counterregulation in diabetic mice.ELISA detection showed that the plasma adrenaline and GCG levels were lower in RH group than those in T1DM group(P<0.01),while the plasma active GLP-1 and SST levels in mice were sig-nificantly higher in RH group(P<0.01).Immunofluorescence analysis showed that intestinal GLP-1 expression and pan-creatic SST secretion increased in RH group(P<0.01),while GCG secretion decreased(P<0.01).Western blot analysis showed that the levels of intestinal active GLP-1 and GLP-1R in RH group were significantly higher than those in T1DM group(P<0.01).CONCLUSION:Recurrent hypoglycemia in T1DM mice leads to increased intestinal GLP-1 expres-sion and secretion,which is closely related to the formation or aggravation of impaired hypoglycemic counterregulation.
作者
靳方馨
赵晶晶
王岩
李敏讷
李如江
郭军堂
JIN Fangxin;ZHAO Jingjing;WANG Yan;LI Minne;LI Rujiang;GUO Juntang(Department of Histology and Embryology,Key Laboratory of Universities in Shandong Province,Shandong Second Medi-cal University,Weifang 261053,China;Department of Pathological Physiology,Shandong Second Medical University,Weifang 261053,China)
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2024年第5期890-898,共9页
Chinese Journal of Pathophysiology
基金
国家自然科学基金面上项目(No.81471048)。
关键词
1型糖尿病
低血糖反调节障碍
胰高血糖素样肽1
肠道
胰腺
type 1 diabetes mellitus
impaired hypoglycemic counterregulation
glucagon-like peptide-1
in-testine
pancreas
作者简介
通讯作者:李如江,E-mail:nuliluck@163.com;通讯作者:郭军堂,E-mail:guojuntang@163.com。
