摘要
Type 2 diabetes is one of the most prevalent and serious metabolic diseases.Under diabetic conditions,chronic hyperglycemia and subsequent induction of oxidative stress deteriorate pancreaticβ-cell function,which leads to the aggravation of type 2 diabetes.Although such phenomena are well known as glucose toxicity,its molecular mechanism remains unclear.In this review article,we describe the possible molecular mechanism forβ-cell dysfunction found in type 2 diabetes,focusing on(1)oxidative stress,(2)pancreatic transcription factors(PDX-1 and MafA)and(3)incretin receptors(GLP-1 and GIP receptors).Under such conditions,nuclear expression levels of PDX-1 and MafA are decreased,which leads to suppression of insulin biosynthesis and secretion.In addition,expression levels of GLP-1 and GIP receptors are decreased,which likely contributes to the impaired incretin effects found in diabetes.Taken together,it is likely that downregulation of pancreatic transcription factors(PDX-1and MafA)and down-regulation of incretin receptors(GLP-1 and GIP receptors)explain,at least in part,the molecular mechanism forβ-cell dysfunction found in type 2 diabetes.
Type 2 diabetes is one of the most prevalent and serious metabolic diseases.Under diabetic conditions,chronic hyperglycemia and subsequent induction of oxidative stress deteriorate pancreaticβ-cell function,which leads to the aggravation of type 2 diabetes.Although such phenomena are well known as glucose toxicity,its molecular mechanism remains unclear.In this review article,we describe the possible molecular mechanism forβ-cell dysfunction found in type 2 diabetes,focusing on(1)oxidative stress,(2)pancreatic transcription factors(PDX-1 and MafA)and(3)incretin receptors(GLP-1 and GIP receptors).Under such conditions,nuclear expression levels of PDX-1 and MafA are decreased,which leads to suppression of insulin biosynthesis and secretion.In addition,expression levels of GLP-1 and GIP receptors are decreased,which likely contributes to the impaired incretin effects found in diabetes.Taken together,it is likely that downregulation of pancreatic transcription factors(PDX-1and MafA)and down-regulation of incretin receptors(GLP-1 and GIP receptors)explain,at least in part,the molecular mechanism forβ-cell dysfunction found in type 2 diabetes.
