Regulation of intercellular adhesion molecule-1 expression on murine glomerular mesangial cells by Oxidized lipoprotein(a).

Objective To investigate the effects of oxidized lipoprotein(a)[Ox-Lp(a)] on proliferation of glomerular mesangial cells(GMCs)and the experssion of intercellular adhesion molecule-1(ICAM-1)in rat model induced by lipopolysaccharide,and explore the possible mechanism of Ox-Lp(a)on the proliferation of rat GMCs.Methods The effect of Ox-Lp(a)with different doses of 2.5,5,10,and 20nmol/L on the proliferation of GMCs was observed.The rats of were divided into three groups:control group,Lp(a)group,Ox-Lp(a)group.After culture(at the end of 12h,24h,48h and 60h),the cultured GMCs and suspension were collected for observation of the proliferative rate of GMCs(MTT),the positive rate of proliferationg cell nuclear antigen(PCNA)(immuno-histo-chemisty),and ICAM-1 activity was determined with ELISA.Results At the end of experiment,compared with control and Lp(a)group,MTT,positive rate of PCNA and ICAM-1 activity of GMCs were more significantly higher in Ox-Lp(a)group;as for dosage-response,MTT,the positive rate of PCNA and ICAM-1 activity of GMCs were increased as Ox-Lp(a)doses increased,a maximal effect was seen for Ox-Lp(a)5nmol/L group.Alon with the continuous increase[Ox-Lp(a)10nmol/L],MTT,the positive rate of PCNA and ICAM-1 activity of GMCs were decreased in Ox-Lp(a)group;As for time-response,MTT,the positive rate of PCNA and ICAM-1 activity were increased as Ox-Lp(a)dosage increased,a maximal effect was seen for Ox-Lp(a)cultured GMCs 48h.ICAM-1 activity showed positive correlation with MTT and the positive rate of PCNA.Conclusion Ox-Lp(a)can significantly affect the rate of GMCs proliferation,this effect is dosage-dependent and time-dependent.Small dosage can stimulate proliferation of GMCs,bigger dosage inhibit the proliferation of GMCs.Ox-Lp(a)can significantly affect ICAM-1 activity,too.ICAM-1 activity is positively correlated with MTT and the positive rate of PCNA.This suggests that the effect of Ox-Lp(a)on GMCs might be associated with ICAM-1.