OBJECTIVEThe renal disease is commonly associated with hyperlipidemia and correlates with glomerular accumulation of atherogenic lipoproteins and mesangial hypercellularity. Therefore, in this study, the authors investigated a possible growth stimulatory effect and mode of action of lipoprotein(a) [Lp(a)] in human mesangial cells HMC, and the effect of Lp(a) on adhesion and migration in human mesangial cells.

METHODSThe DNA synthesis of HMC was measured by (3)H-thymidine incorporation. The cell adhesion was detected by the expression of vinculin by means of indirect immunofluorescence. The cell migration was observed under the microscope.

RESULTSThe incubation of HMC with Lp(a) for 24 hours induced a significant dose-dependent proliferation of HMC [Lp(a): 5 microg, 10 microg, 25 microg, 50 microg/ml vs. control 0 microg/ml; (3)H-TdR incorporation (x 10(3)cpm): 1.69 +/- 0.48, 3.59 +/- 0.68, 4.14 +/- 0.78, 4.05 +/- 0.55 vs. 1.64 +/- 0.31, P < 0.01]. The vinculin staining by indirect immunofluorescence showed positive result when HMC was incubated with 10 microg/ml Lp(a) for 24 hours, while vinculin was negative when HMC was incubated with 0 microg/ml Lp(a) as the control of the study. The incubation of HMC with 10 microg/ml Lp(a) for 72 hours demonstrated significant cell migration effect compared to the control of 0 microg/ml. (16.2/LP vs. 2.4/LP, P < 0.01).

CONCLUSIONLp(a) could stimulate a proliferation, adhesion and migration effect on human mesangial cells.