Klotho expression in hyperphosphate-induced calcified vascular smooth muscle cells

doi:10.16150/j.1671-2870.2017.04.007

Abstract

Abstract: Objective: To investigate the changes of Klotho expression in rat vascular smooth muscle cells (VSMCs) calcification induced by high phosphate. Methods: Rat VSMCs was cultured in vitro, the proliferation of VSMCs induced by different concentrations of phosphate was detected by cell counting kit-8 (CCK-8). VSMCs were treated with high phosphate (3 mmol/L) for 3 days or 6 days, and the calcification of VSMCs was evaluated by alizarin red staining. The activity of alkaline phosphatase (ALP) and calcium content in VSMCs were detected by ALP assay kit and calcium colorimetric assay kit, respectively. The expression of mRNA and protein of bone morphogenetic protein 2 (BMP-2), Runt related transcription factor 2 (Runx2) and Klotho were detected by quantitative real-time polymerase chain reaction (qrt-PCR) and Western blotting (WB). Results: Higher-phosphate media inhibited the proliferation of VSMCs. After being incubated in high-phosphate media for 6 days, calcified nodules were observed with alizarin red staining and calcium content was significantly increased; qrt-PCR demonstrated that levels of BMP-2 and Runx2 mRNA and protein were increased and the expressions of Klotho mRNA and protein levels were decreased. Conclusions: Klotho might be involved in the hyperphosphate-induced calcification and phenotype changes in VSMCs.

Key words: Vascular smooth muscle cells, Klotho, High phosphate, Calcification

CLC Number:

R331.3⁺1

JIANG Zuanhong, CHEN Zijin, WANG Zhiyu, CHEN Qiujing, LU Lin, MA Xiaobo, YU Haijin, CHEN Xiaonong. Klotho expression in hyperphosphate-induced calcified vascular smooth muscle cells[J]. Journal of Diagnostics Concepts & Practice, 2017, 16(04): 377-383.

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