title: PPARgamma transcriptionally regulates the expression of insulin-degrading enzyme in primary neurons.
abstract: Insulin-degrading enzyme (IDE) is a protease that has been demonstrated to play a key role in degrading both Abeta and insulin and deficient in IDE function is associated with Alzheimer's disease (AD) and type 2 diabetes mellitus (DM2) pathology. However, little is known about the cellular and molecular regulation of IDE expression. Here we show IDE levels are markedly decreased in DM2 patients and positively correlated with the peroxisome proliferator-activated receptor gamma (PPARgamma) levels. Further studies show that PPARgamma plays an important role in regulating IDE expression in rat primary neurons through binding to a functional peroxisome proliferator-response element (PPRE) in IDE promoter and promoting IDE gene transcription. Finally, we demonstrate that PPARgamma participates in the insulin-induced IDE expression in neurons. These results suggest that PPARgamma transcriptionally induces IDE expression which provides a novel mechanism for the use of PPARgamma agonists in both DM2 and AD therapies.
authors.affiliation: Protein Science Key Laboratory of the Ministry of Education, Department of Biological Sciences and Biotechnology, School of Medicine, Tsinghua University, Beijing 100084, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Du
authors.forename: Lang
authors.initials: L
authors.lastname: Zhang
authors.forename: Shubo
authors.initials: S
authors.lastname: Liu
authors.forename: Chi
authors.initials: C
authors.lastname: Zhang
authors.forename: Xiuqing
authors.initials: X
authors.lastname: Huang
authors.forename: Jian
authors.initials: J
authors.lastname: Li
authors.forename: Nanming
authors.initials: N
authors.lastname: Zhao
authors.forename: Zhao
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000544:Alzheimer Disease / Q000201:enzymology; D000818:Animals; D001483:Base Sequence; D003924:Diabetes Mellitus, Type 2 / Q000201:enzymology; D005260:Female; D006624:Hippocampus / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D007339:Insulysin / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009474:Neurons / Q000187:drug effects / Q000201:enzymology*; D047495:PPAR gamma / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014158:Transcription, Genetic
chemical_list: D007328:Insulin; D047495:PPAR gamma; D007339:Insulysin