title: Pyridoxal phosphate prevents progression of diabetic nephropathy.
abstract: BACKGROUND
  We have demonstrated that pyridoxal 5'-phosphate (PLP), an active form of vitamin B6, inhibits formation of advanced glycation end-products (AGEs) by trapping 3-deoxyglucosone. The present study aimed to clarify if PLP could exert beneficial effects on nephropathy in diabetic rats.
  
  
  METHODS
  Streptozotocin (STZ)-induced diabetic rats were treated by oral administration of PLP or pyridoxamine (PM), another active form of vitamin B6, at a dose of 600 mg/kg/day for 16 weeks. AGEs [imidazolone, N(epsilon)-(carboxymethyl)lysine (CML) and N(2)-carboxyethyl-2'-deoxyguanosine (CEdG)], transforming growth factor-beta1 (TGF-beta1), type 1 collagen and fibronectin were detected in the kidneys using immunohistochemistry. Gene expression of TGF-beta1 and receptor for AGEs (RAGEs) in the kidneys was determined using real-time quantitative polymerase chain reaction.
  
  
  RESULTS
  Administration of PLP significantly inhibited albuminuria, glomerular hypertrophy, mesangial expansion, and interstitial fibrosis as compared with diabetic rats. PLP markedly inhibited accumulation of AGEs such as imidazolone, CML and CEdG, a DNA-linked AGE, in glomeruli. PLP significantly inhibited expression of TGF-beta1, type 1 collagen, fibronectin and RAGE in the kidneys. PLP was superior to PM in inhibiting accumulation of AGEs, expression of TGF-beta1, type 1 collagen, and fibronectin, and the development of diabetic nephropathy.
  
  
  CONCLUSIONS
  PLP prevented progression of nephropathy in STZ-induced diabetic rats by inhibiting formation of AGEs. PLP is considered a promising active form of vitamin B6 for the treatment of AGE-linked disorders such as diabetic nephropathy.
authors: Department of Clinical Preventive Medicine, Nagoya University Hospital, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8560, Japan.
authors: Sakurako
authors: S
authors: Nakamura
authors: Hongyan
authors: H
authors: Li
authors: Ayinuer
authors: A
authors: Adijiang
authors: Monika
authors: M
authors: Pischetsrieder
authors: Toshimitsu
authors: T
authors: Niwa
mesh_terms: D000284:Administration, Oral; D000818:Animals; D003928:Diabetic Nephropathies / Q000188:drug therapy* / Q000473:pathology; D005260:Female; D005353:Fibronectins / Q000378:metabolism; D017127:Glycation End Products, Advanced; D007668:Kidney / Q000378:metabolism; D011732:Pyridoxal Phosphate / Q000494:pharmacology*; D011733:Pyridoxamine / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic / Q000378:metabolism; D013311:Streptozocin / Q000494:pharmacology; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D025101:Vitamin B 6 / Q000378:metabolism
chemical_list: D005353:Fibronectins; D017127:Glycation End Products, Advanced; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic; D053773:Transforming Growth Factor beta1; D011732:Pyridoxal Phosphate; D013311:Streptozocin; D011733:Pyridoxamine; D025101:Vitamin B 6