title: High glucose induces renal tubular epithelial injury via Sirt1/NF-kappaB/microR-29/Keap1 signal pathway.
abstract: OBJECTIVE
  Diabetic nephropathy (DN) is a serious complication that commonly confronted by diabetic patients. A common theory for the pathogenesis of this renal dysfunction in diabetes is cell injury, inflammation as well as oxidative stress. In this content, the detailed molecular mechanism underlying high glucose induced renal tubular epithelial injury was elaborated.
  
  
  METHODS
  An in vivo rat model of diabetes by injecting streptozotocin (STZ) and an in vitro high glucose incubated renal tubular epithelial cell (HK-2) model were used. Expression levels of Keap1, nuclear Nrf2 and p65 were determined by western blotting. Level of microR-29 (miR-29) was assessed using quantitative RT-PCR. Combination of p65 and miR-29 promotor was assessed using chromatin immunoprecipitation. Keap1 3'-UTR activity was detected using luciferase reporter gene assay. Cell viability was determined using MTT assay.
  
  
  RESULTS
  In diabetic rat, miR-29 was downregulated and its expression is negatively correlated with both of serum creatinine and creatinine clearance. In high glucose incubated HK-2 cell, deacetylases activity of Sirt1 was attenuated that leads to decreased activity of nuclear factor kappa B (NF-κB). NF-κB was demonstrated to regulate miR-29 expression by directly binding to its promotor. The data of luciferase assay showed that miR-29 directly targets to Keap1 mRNA. While high glucose induced down regulation of miR-29 contributed to enhancement of Keap1 expression that finally reduced Nrf2 content by ubiquitinating Nrf2. Additionally, overexpression of miR-29 effectively relieved high glucose-reduced cell viability.
  
  
  CONCLUSIONS
  High glucose induces renal tubular epithelial injury via Sirt1/NF-κB/microR-29/Keap1 signal pathway.
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Soochow University, Suzhou, 215006, China. zl66060@163.com.
authors.forename: Ling
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Soochow University, Suzhou, 215006, China. xdydexu@163.com.
authors.forename: De-Yu
authors.initials: DY
authors.lastname: Xu
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Soochow University, Suzhou, 215006, China. s_wengang@163.com.
authors.forename: Wen-Gang
authors.initials: WG
authors.lastname: Sha
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Soochow University, Suzhou, 215006, China. shenlei063@163.com.
authors.forename: Lei
authors.initials: L
authors.lastname: Shen
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Soochow University, Suzhou, 215006, China. gyuanlu@163.com.
authors.forename: Guo-Yuan
authors.initials: GY
authors.lastname: Lu
authors.affiliation: Department of Endocrinology, The First Affiliated Hospital of Soochow University, Suzhou, 215006, China. XiaiaYin@163.com.
authors.forename: Xia
authors.initials: X
authors.lastname: Yin
authors.affiliation: Department of Rheumatology, The First Affiliated Hospital of Soochow University, 188 shizi Rd., Suzhou, 215006, People's Republic of China. mingjWjw@163.com.
authors.forename: Ming-Jun
authors.initials: MJ
authors.lastname: Wang
mesh_terms: D020413:3' Untranslated Regions; D000818:Animals; D002470:Cell Survival; D047369:Chromatin Immunoprecipitation; D003404:Creatinine / Q000097:blood; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism / Q000473:pathology; D003928:Diabetic Nephropathies / Q000378:metabolism; D004195:Disease Models, Animal; D004847:Epithelial Cells / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D000072019:Kelch-Like ECH-Associated Protein 1; D007684:Kidney Tubules / Q000166:cytology / Q000473:pathology*; D008297:Male; D035683:MicroRNAs / Q000378:metabolism*; D051267:NF-E2-Related Factor 2 / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000378:metabolism; D029543:Nucleocytoplasmic Transport Proteins / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction; D056564:Sirtuin 1 / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: D020413:3' Untranslated Regions; D047908:Intracellular Signaling Peptides and Proteins; C486610:KEAP1 protein, rat; D000072019:Kelch-Like ECH-Associated Protein 1; C526366:MIRN29 microRNA, rat; D035683:MicroRNAs; D051267:NF-E2-Related Factor 2; D016328:NF-kappa B; D009363:Neoplasm Proteins; C495637:Nfe2l2 protein, rat; D029543:Nucleocytoplasmic Transport Proteins; C063447:p65 oncofetal mRNA transport protein, rat; D003404:Creatinine; C488368:Sirt1 protein, rat; D056564:Sirtuin 1; D005947:Glucose