Effect of cytokine response modifier A on the expression of interleukin-1β converting enzyme in chondrocytes / 中华风湿病学杂志

ABSTRACT

Objective To investigate the effects of chitosan(CS)/pcDNA3.1(+) CrmA on the expression of interleukin-13 (IL-1β3) converting enzyme (ICE) and IL-1β in chondrocytes.Methods Rabbit chondrocytes were isolated and cultured.Chondrocytes were treated with PBS,10 μg/ml CS/pcDNA3.1(+) and CS/pcDNA3.1 (+) CrmA respectively for 6 hours.Then 10 ng/ml IL-1β was added into the culture medium.After 48 hours,the messenger RNA and protein expression of ICE and IL-1β in chondrocytes were detected by using real time polymerase chain reaction and western blotting.Results In CS/pcDNA3.1 (+) CrmA treated group (0.52 ±0.09),the mRNA expression of ICE inchondrocytes was significantly inhibited compared withcorresponding samples of CS/pcDNA3.1 (+) group (0.84±0.11,t=4.42,P＜0.01) and PBS group (1.00±0.10,t=6.58,P＜0.01).ICE protein expression in CS/pcDNA3.1 (+) CrmA treated group (0.20±0.03) was markedly lower than CS/pcDNA3.1 (+) (0.37±0.05,t=4.85,P＜0.01) and PBS treated group (0.44±0.07,t=6.68,P＜0.01).There was no significant difference of ICE mRNA and protein expressions in chondrocytes between CS/pcDNA3.1(+) group and PBS group.Significant difference of IL-1β mRNA expression was found in the three groups.IL-1 β mRNA expression level was significantly lower in CS/pcDNA3.1(+) CrmA treated group (0.55± 0.08) than CS/pcDNA3.1(+) (0.69±0.06,t=3.50,P＜0.01) and PBS group (0.99±0.04,t=11.12,P＜0.01) of chondrocytes.IL-1β protein expression level of chondrocytesin CS/pcDNA3.1(+) CrmA group (0.230±0.020) was significantly lower than CS/pcDNA3.1 (+) (0.450±0.060,t=5.07,P＜0.01)and PBS groups (0.610±0.090,t=8.70,P＜0.01) of cells.Significant difference of IL-1β mRNA and protein expression between CS/pcDNA3.1 (+) and PBS group was also observed (t=7.61,P＜0.01;t=3.63,P＜0.01).Conclusion CrmA mediated by chitosan can significantly suppress the mRNA and protein expression of ICE,thus down regulat the expression of IL-1β,which may be one of the mechanisms of CS/pcDNA3.1 (+) CrmA in the treatment of osteoarthritic cartilage degeneration.