title: Calcium-dependent expression of transient receptor potential canonical type 3 channels in patients with chronic kidney disease.
abstract: It is unknown whether extracellular calcium may regulate the expression of transient receptor potential canonical type 3 (TRPC3) channels in patients with chronic kidney disease. Using quantitative in-cell Western assay we compared the expression of TRPC3 channel protein in monocytes from 20 patients with chronic kidney disease and 19 age- and sex-matched healthy control subjects. TRPC3 channels were identified by immunoblotting using specific antibodies and TRPC3 protein was further confirmed by mass spectrometry. We observed a significant increase of TRPC3 channel protein expression in patients with chronic kidney disease compared to healthy control subjects (normalized expression, 0.42±0.06 vs. 0.19±0.03; p<0.01). Expression of TRPC3 was significantly inversely correlated with estimated glomerular filtration rates (Spearman r=-0.41) or serum calcium concentration (Spearman r=-0.34). During a hemodialysis session serum calcium concentrations significantly increased, whereas the expression of TRPC3 channels and calcium influx significantly decreased. In vitro studies confirmed that higher calcium concentrations but not magnesium, barium nor sodium concentrations significantly decreased TRPC3 expression in human monocytes. This study indicates that reduced extracellular calcium concentrations up-regulate TRPC3 channel protein expression in patients with chronic kidney disease.
authors.affiliation: Odense University Hospital, and University of Southern Denmark, Institute of Molecular Medicine, Cardiovascular and Renal Research, Denmark.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Katharina
authors.initials: K
authors.lastname: Krueger
authors.forename: Anahit
authors.initials: A
authors.lastname: Hovsepian
authors.forename: Martin
authors.initials: M
authors.lastname: Tepel
authors.forename: Florian
authors.initials: F
authors.lastname: Thilo
mesh_terms: D000368:Aged; D002118:Calcium / Q000097:blood / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007676:Kidney Failure, Chronic / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D050052:TRPC Cation Channels / Q000235:genetics* / Q000378:metabolism
chemical_list: D050052:TRPC Cation Channels; C104603:TRPC3 cation channel; D002118:Calcium