Effect of caveolin-1 on renal injury and the expression of tight junction protein in MRL/lpr mice kidney / 中华风湿病学杂志

ABSTRACT

Objective To study the effect of caveolin-1 on renal injury and the expression of tight junction proteins in MRL/lpr mice kidney.Methods The mice were divided into 4 groups5 mice in the normal control group (BALB/c mice);the MRL/lpr lupus mice (n=18) were randomly divided into the MRL/lpr group in which 6 mice were included;the negative control group in which 6 mice were included;the caveolin1 transfection group in which 6 mice were included.The changes of urine protein,the levels of urea (BUN) and creatinine (Cr) were detected.The expressions of claudin-5,occludin,ZO-1 and caveolin-1 protein were determined by western bloting.Analysis of variance was used to determine statistical significant differences between the two groups.A significance level of 0.05 was considered as signigicant.Results Compared with the control group,24 h urine protein [(2 894±437) mg,(412±72) mg],BUN [(8.7±1.5) mmol/L,(6.9±0.4) mmol/L],Cr [(106±22) μmol/L,(85±4) μmol/L] were significantly increased,level of caveolin-1 protein increased (265±17,61±6),the level of occludin (114±12,190±12),claudin-5 (60±5,80±6) and ZO-1 (98±11,206±15) protein decreased in the MRL/lpr group (P＜0.05).After caveolin-1 transfection,the levels of urinary protein [(1 253±249) mg,(2 894±437) mg],BUN [(6.5±1.3) mmol/L,(8.7±1.5) mmol/L],Cr [(78±17) μmol/L,(106±22)μmol/L] were significantly decreased,and the levels of occludin (218±16,114±12),claudin-5 (87±6,60±5)ZO-1 (313±17,98±11) were increased (P＜0.05).Conclusion The expression of caveolin-1 protein in the renal tissues of lupus nephritis increases.Caveolin-1 can reduce the expression of tight junction proteins and contribute to progres-sion of lupus nephritis.