title: Inhibition of advanced glycation end product formation by Pu-erh tea ameliorates progression of experimental diabetic nephropathy.
abstract: Accumulation of advanced glycation end products (AGEs) has been implicated in the development of diabetic nephropathy. We investigated the effects of Pu-erh tea on AGE accumulation associated with diabetic nephropathy. Although it did not affect blood glucose levels and insulin sensitivy, Pu-erh tea treatment for 8 weeks attenuated the increases in urinary albumin, serum creatinine, and mesangial matrix in db/db mice. We found that Pu-erh tea prevented diabetes-induced accumulation of AGEs and led to a decreased level of receptor for AGE expression in glomeruli. Both production and clearance of carbonyl compounds, the main precursor of AGE formation, were probably attenuated by Pu-erh tea in vivo independent of glyoxalase I expression. In vitro, HPLC assay demonstrated Pu-erh tea could trap methylglyoxal in a dose-dependent manner. Our study raises the possibility that inhibition of AGE formation by carbonyl trapping is a promising approach to prevent or arrest the progression of diabetic complications.
authors.affiliation: State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, People's Republic of China.
authors.forename: Shi-Jun
authors.initials: SJ
authors.lastname: Yan
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
authors.forename: Di-Na
authors.initials: DN
authors.lastname: Zhu
authors.forename: Shao-Chen
authors.initials: SC
authors.lastname: Guo
authors.forename: Wen-Feng
authors.initials: WF
authors.lastname: Xin
authors.forename: Yan-Fang
authors.initials: YF
authors.lastname: Yang
authors.forename: Xiao
authors.initials: X
authors.lastname: Cong
authors.forename: Tao
authors.initials: T
authors.lastname: Ma
authors.forename: Pei-Ping
authors.initials: PP
authors.lastname: Shen
authors.forename: Jun
authors.initials: J
authors.lastname: Sheng
authors.forename: Wen-Sheng
authors.initials: WS
authors.lastname: Zhang
mesh_terms: D000818:Animals; D028241:Camellia sinensis / Q000737:chemistry*; D003928:Diabetic Nephropathies / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D018450:Disease Progression; D015536:Down-Regulation; D005260:Female; D017127:Glycation End Products, Advanced / Q000378:metabolism*; D006801:Humans; D007678:Kidney Glomerulus / Q000378:metabolism; D008297:Male; D051379:Mice; D010936:Plant Extracts / Q000008:administration & dosage*; D013662:Tea / Q000737:chemistry*
chemical_list: D017127:Glycation End Products, Advanced; D010936:Plant Extracts; D013662:Tea