轻度蛋白聚糖耗竭后软骨基质修复过程中转化生长因子-β、核心蛋白聚糖和双糖链蛋白聚糖mRNA水平的早期升高。

Early elevation of transforming growth factor-beta, decorin, and biglycan mRNA levels during cartilage matrix restoration after mild proteoglycan depletion.

作者信息

van der Kraan P M, Glansbeek H L, Vitters E L, van den Berg W B

机构信息

Department of Rheumatology, University Hospital Nijmegen, The Netherlands.

出版信息

J Rheumatol. 1997 Mar;24(3):543-9.

PMID:9058663

Abstract

OBJECTIVE

To elucidate the role of transforming growth factor-beta (TGF-beta) and the small proteoglycans biglycan and decorin in the repair of articular cartilage after proteoglycan depletion.

METHODS

Limited and reversible proteoglycan depletion was induced by injection of murine knee joints with 0.5% papain. Proteoglycan content of patellar cartilage was examined by safranin O staining on histological sections and overall proteoglycan synthesis was measured by incorporation of 35S sulfate. Changes in mRNA expression of TGF-beta, aggrecan, decorin, and biglycan were determined by semiquantitative reverse transcription polymerase chain reaction.

RESULTS

Papain injection led to rapid depletion of proteoglycans, which was partly overcome 7 days after injection, while total replenishment of the cartilage matrix with proteoglycans was observed on Day 24. The incorporation of radiolabeled sulfate in patellar proteoglycans was initially decreased (up to Day 3), but significantly enhanced on Days 4 and 7 after papain injection. Upregulation of TGF-beta, decorin, and biglycan mRNA in patellar cartilage was observed on Day 2, markedly before elevation of overall proteoglycan synthesis. mRNA levels were less augmented on Day 7, and on Day 24 all messenger RNA levels had returned to control values. As well, in the soft tissue adjoining the patella swift upregulation of TGF-beta mRNA was observed.

CONCLUSION

mRNA of both TGF-beta and the small proteoglycans decorin and biglycan are elevated at an early phase during cartilage repair after moderate proteoglycan depletion, implying a functional role for these molecules in this repair process.

摘要

目的

阐明转化生长因子-β（TGF-β）以及小分子蛋白聚糖双糖链蛋白聚糖和核心蛋白聚糖在蛋白聚糖耗竭后关节软骨修复中的作用。

方法

通过向小鼠膝关节注射0.5%木瓜蛋白酶诱导有限且可逆的蛋白聚糖耗竭。通过对组织学切片进行番红O染色检查髌软骨的蛋白聚糖含量，并通过掺入35S硫酸盐来测量总体蛋白聚糖合成。通过半定量逆转录聚合酶链反应确定TGF-β、聚集蛋白聚糖、核心蛋白聚糖和双糖链蛋白聚糖的mRNA表达变化。

结果

注射木瓜蛋白酶导致蛋白聚糖迅速耗竭，注射后7天部分得到克服，而在第24天观察到软骨基质中蛋白聚糖完全补充。髌蛋白聚糖中放射性标记硫酸盐的掺入最初减少（直至第3天），但在木瓜蛋白酶注射后第4天和第7天显著增强。在第2天观察到髌软骨中TGF-β、核心蛋白聚糖和双糖链蛋白聚糖mRNA上调，明显早于总体蛋白聚糖合成增加。第7天mRNA水平增加较少，第24天所有信使RNA水平恢复到对照值。同样，在髌骨周围的软组织中观察到TGF-β mRNA迅速上调。