Caveolin-1에 의한 연골세포의 분화와 COX-2 발현의 조절 = Regulation of chondrocyte differentiation and cyclooxygenase-2 expression by caveolin-1

국문 초록 (Abstract)

Caveolin-1은 caveolae 막구성물질에서 가장 주요한 구성단백질중의 하나이다. 본 연구에서는 연골세포의 분화와 COX-2 단백질의 발현에 관련된 caveolin-1의 기능을 규명하고자 하였다. Caveolin-1을 과발현시켰을 때 연골세포의 탈분화가 일어남을 확인할 수 있었으며 COX-2의 발현도 증가됨을 볼 수 있었다. 또한, 주요 MAP kinase인 ERK-1/-2와 p38 kinase도 활성화됨을 확인하였다. 이러한 결과를 종합해 볼때, 연골세포의 탈분화와 COX-2의 발현은 이 두가지 MAP kinase의 상반된 조절에 의해 이루어짐을 알 수 있었다.

다국어 초록 (Multilingual Abstract)

Caveolin-1 is a principal component of caveolae membranes in vivo. We investigated the role of caveolin-1 in the regulation of the chondrocyte differentiation and function inducing cyclooxygenase (COX-2) expression. Ectopic expression of caveolin-1 caused dedifferentiatin, as indicated by the inhibition of type II collagen expression and proteoglycan synthesis, stimulated COX-2 expression. Our previous study indicated that dedifferentiation of articular chondrocytes is regulated by the converse functions of two MAP kinase subtypes. Overexpression of caveolin-1 stimulated activation of ERK-1/-2 and p38 kinase. Inhibition of ERK-1/-2 with PD98059 rescued caveolin-1 induced dedifferentiation, whereas inhibition of p38 kinase with SB203580 enhanced dedifferentiation. Similar to the pattern of dedifferentiation, COX-2 expression was oppositly regulated by ERK-1/-2 and p38 kinase in caveolin-1 transfected cells. Therefore, our results collectively indicate that ERK-1/-2 and p38 kinase oppositely regulate caveolin-1 induced dedifferentiation and COX-2 expression.