title: [Expression of calcineurin in podocytes in response to endoplasmic reticulum stress in diabetic nephropathy].
abstract: OBJECTIVE
  To investigate the regulation of calcineurin (CaN) by endoplasmic reticulum stress (ERS) in podocytes in vitro and in vivo at the stage microalbuminuria in diabetic nehropathy (DN).
  
  
  METHODS
  The urinary albumin excretions of C57BLKS/J (Lepr) db/db and db/m mice at the ages of 6, 9, and 12 weeks were measured. The expressions of CaN and synaptopodin of these mice were observed. In immortalized mouse podocytes, the expression of podocyte CaN incubated with different concentrations of paltimate was quantitatively determined by real-time PCR. The changes of CaN incubated with paltimate with or without ursodeoxy-cholic acid (UDCA) were analyzed by confocal microscopy and Western blotting.
  
  
  RESULTS
  As urine protein increased, the expression of CaN was enhanced and the expression of synaptopodin was reduced in early stage DN db/db mice potocytes. In immortalized mouse podocytes, as the concentrations of palmitate increased, CaN mRNA increased. By confocal microscopy, the fluorescence intensity of CaN increased in palmitate treatment group. After co-incubation with palmitate and UDCA, the fluorescence intensity decreased. The similar results were shown by Western blotting.
  
  
  CONCLUSIONS
  At the stage of microalbuminuria in DN, ERS in podocytes up-regulates the expression of CaN.
authors.affiliation: Department of Nephrology,PUMC Hospital,CAMS and PUCM,Beijing 100730.
authors.forename: Rong-rong
authors.initials: RR
authors.lastname: Hu
authors.affiliation: Department of Nephrology,PUMC Hospital,CAMS and PUCM,Beijing 100730.
authors.forename: Jie
authors.initials: J
authors.lastname: Ma
authors.affiliation: Department of Nephrology,PUMC Hospital,CAMS and PUCM,Beijing 100730.
authors.forename: Jian-ling
authors.initials: JL
authors.lastname: Tao
authors.affiliation: Department of Nephrology,PUMC Hospital,CAMS and PUCM,Beijing 100730.
authors.forename: Yu-bing
authors.initials: YB
authors.lastname: Wen
authors.affiliation: Department of Nephrology,Cangzhou City People's Hospital,Cangzhou,Hebei 061000,China.
authors.forename: Cui
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Department of Nephrology,PUMC Hospital,CAMS and PUCM,Beijing 100730.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Nephrology,PUMC Hospital,CAMS and PUCM,Beijing 100730.
authors.forename: Hang
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Nephrology,PUMC Hospital,CAMS and PUCM,Beijing 100730.
authors.forename: Ming-xi
authors.initials: MX
authors.lastname: Li
authors.affiliation: Department of Nephrology,PUMC Hospital,CAMS and PUCM,Beijing 100730.
authors.forename: Xue-mei
authors.initials: XM
authors.lastname: Li
authors.affiliation: Department of Nephrology,PUMC Hospital,CAMS and PUCM,Beijing 100730.
authors.forename: Xue-wang
authors.initials: XW
authors.lastname: Li
mesh_terms: D000818:Animals; D019703:Calcineurin / Q000378:metabolism*; D002478:Cells, Cultured; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism; D003928:Diabetic Nephropathies / Q000378:metabolism*; D059865:Endoplasmic Reticulum Stress; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008840:Microfilament Proteins / Q000378:metabolism; D050199:Podocytes / Q000378:metabolism*
chemical_list: D008840:Microfilament Proteins; C503968:Synpo protein, mouse; D019703:Calcineurin