Journal: Kidney international

Article Title: Vitamin D receptor agonists increase klotho and osteopontin while decreasing aortic calcification in mice with chronic kidney disease fed a high phosphate diet

doi: 10.1038/ki.2012.322

Figure Lengend Snippet: (A) Arterial medial osteopontin (OPN) levels were increased by VDRA treatment. (i) OPN expression was low but detectable in the aortic media of CKD mice fed a high phosphate diet (CKD+HP). VDRA treatment increased smooth muscle cell expression of OPN in the aortic media in (ii) CKD+HP+C30 animal; and (iii) CKD+HP+P300 animal. Arrows point to aortic medial cells expressing OPN. Scale bars are 30 μm and objective is 40X. (B) Quantitation of OPN immunostaining showed no OPN expression in aortas from non-CKD controls, weak staining in CKD high phosphate-fed mice, and increased levels in VDRA-treated CKD mice (mean ± s.e.m., n =3 for all except CKD+HP+paricalcitol, n =5 where P100 and P300 samples were grouped). (C) Treatment of cultured VSMCs with 50 nM paricalcitol increased OPN levels in the media (significantly higher levels by ELISA at 48hr compared to time zero, ** P <0.001). Klotho (2 ng/mL) with/without FGF23 (2 ng/mL) did not upregulate OPN secretion. Three wells were sampled per time-point per treatment group, data are mean ± s.e.m. EtOH = ethanol control, KL = klotho, P50 = paricalcitol 50 nM.

Article Snippet: The following assays were used: QuantiChromTM Urea Assay Kit (BioAssay Systems, Hayward, CA) for BUN; o -cresolphthalein complexone kit from Teco Diagnostics (Anaheim, CA) for calcium; standard bioanalyzer at Phoenix Central Laboratory (Everett, WA) for phosphate; mouse FGF23 C-terminus ELISA kit (Immutopics, San Clemente, CA); DuoSet mouse osteopontin ELISA kit (R&D Systems, Minneapolis, MN); mouse intact PTH enzyme-linked immunosorbent assay kits (ALPCO Diagnostics, Salem, NH and Immutopics).

Techniques: Expressing, Quantitation Assay, Immunostaining, Staining, Cell Culture, Enzyme-linked Immunosorbent Assay, Control