Simvastatin inhibits tissue factor and plasminogen activator inhibitor-1 secretion by peripheral blood mononuclear cells in patients with primary nephrotic syndrome.

BACKGROUND Tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1) activity and/or expression are upregulated in nephrotic syndrome. Despite extensive research on antithrombotic effect of statins, little is known about their effects on TF and PAI-1 expression in peripheral blood mononuclear cells in patients with primary nephrotic syndrome(PNS). METHODS PBMCs were isolated by gradient centrifugation from 25 individuals with PNS and 25 healthy subjects. TF and PAI-1 mRNA were detected by RT-PCR. The activities of TF and PAI-1 were determined with ELISA and chromogenic substrate method, respectively. The patients with PNS were then treated with simvastatin 40 mg/day for 2 weeks. The activities of TF, PAI-1 and TF, PAI-1 mRNA of PBMCs were also measured. RESULTS Compared with controls, patients with PNS had increased TF, PAI-1 secretion by PBMCs at baseline (70.4 +/- 15.6 ng/l vs. 32.7 +/- 8.2 ng/l; 15.9 +/- 2.4 (x10(3) AU/l) vs. 3.9 +/- 1.5(x10(3) AU/l), P<0.01) and after stimulated by LPS (10 ng/mL) (89.2 +/- 13.4 ng/l vs. 49.5 +/- 10.3 ng/l; 23.8 +/- 3.3 (x10(3) AU/l) vs. 8.1 +/- 2.1, P<0.01). The simvastatin treatment resulted in a significant effect in decreasing TF and PAI-1 (69.1 +/- 14.6 ng/l vs. 89.2 +/- 13.4 ng/l; 16.5 +/- 4.8 (x10(3) AU/l) vs. 23.8 +/- 3.3 (x10(3) AU/l), P<0.05) secretion in PBMCs. Increased TF and PAI-1 mRNA expression in PBMCs from PNS (1.034 +/- 0.043 and 0.982 +/- 0.056, respectively) as compared to the control (0.221 +/- 0.015 and 0.221 +/- 0.015, respectively) (p<0.01). two-week simvastatin treatment resulted in significant decrease of TF (0.535 +/- 0.028, p<0.01) and PAI-1 mRNA (0.602 +/- 0.037, p<0.01). CONCLUSION TF and PAI-1 mRNA expression and activities in PBMCs were increased in PNS. Simvastatin reduced TF and PAI-1 expression and activity in PBMCs. These effects may partially be relevant to the clinical benefits of statins in the treatment of PNS.