Effects of SPARC and its peptide on proliferation and apoptosis of human mesangial cells cultured in vitro / 中华肾脏病杂志

ABSTRACT

Objective To investigate the effects of SPARC (secreated protein acidic and rich in cysteine) and its peptide on proliferation, apoptosis and cell cycle of human mesangial cells cultured in vitro, and explore the possible mechanism. Methods Mesangial cells were incubated in the media with various concentrations of SPARC and its peptide cultured in vitro. Cell proliferation was assessed by MTT colorimetric assay. Cell cycle and apoptosis index were analyzed by flow cytometry. The expression of cyclinD1 and p21Wafl proteins in response to SPARC and its peptide in HMC was determined by Western blot. Results Various concentrations of SPARC and its peptide could significantly inhibit the proliferation of mesangial cells in dose- and time-dependent manner, regulate the cell cycle at phrase G-0/G1 increased while cells phrase S reduced, and could also induce apoptosis. Under the stimulation of SPARC and its peptide, the expression of cyclinDl in HMC decreased markedly meanwhile the expression of p21Wafl increased significantly. Conclusions SPARC and its peptide can effectively inhibit HMC proliferation and regulate cell cycle progression. The mechanism may be mediated by inhibiting cyclinDl and stimulating p21Wafl expression, subsequently blocking cells passing through G-S check point, which will be useful for treating mesangial proliferative glomerulonephritis.