ISSN:
0021-9541
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
Rabbit articular chondrocytes were incubated with recombinant transforming-growth-factor-β 1, (rhTGF-β1) and its effect on newly synthesized proteoglycan measured. rhTGF-β1 stimulated proteoglycan synthesis at a concentration as low as 5 ng/ml without further increase in radiosulfate incorporation up to 50 ng/ml. The quantitative increase in radiosulfate incorporation in rh-TGF-β1-treated chondrocytes was greater in the cell-associated culture compartment than in the medium compartment. rhTGF-β1 promoted an increased proteoglycan retention in the cell-associated compartment as evidenced by an increase in the t 1/2 retention from 8 h to 11 h. Specific enhanced synthesis of [35S]-methionine-labeled core proteins was seen in rh-TGF-β1-treated chondrocytes. rh-TGF-β1 increased the synthesis of the 2 core proteins derived from hydrodynamically large proteoglycans. They possessed apparent molecular weights of 〉 480 kD and 390 kD after 3-5% acrylamide gel electrophoresis. A compartmental analysis revealed that the cell-associated culture compartment contained only the larger of the 2 core proteins derived from large proteoglycans. Two other core proteins with apparent molecular weights 52 kD and 46 kD were also stimulated by rhTGF-β1. These results indicated that TGF-β probably plays a significant role in stimulating proteoglycan core protein synthesis in articular chondrocytes and therefore may be an important growth factor in the restoration of cartilage extracellular matrix after injury.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcp.1041490119
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