Na. Visser et al., THE EFFECTS OF LOADING ON THE SYNTHESIS OF BIGLYCAN AND DECORIN IN INTACT MATURE ARTICULAR-CARTILAGE IN-VITRO, Connective tissue research, 30(4), 1994, pp. 241-250
Sesamoid bone cartilage from the metacarpophalangeal joints of 5-year-
old cows was cultured intact on its bone support. The incorporation of
sulfate increased similarly in experimental cartilage that was subjec
ted to cyclic loading (0.2 MPa, 0.2 Hz) for a week and in control cart
ilage that was cultured without loading. The synthesis of a population
of small macromolecules decreased in the cultured controls, but was m
aintained at a constant level in the experimental samples. This popula
tion was isolated through Sepharose CL-2B chromatography. Subsequent a
pplication to Sepharose CL-4B yielded two distinct peaks. One containe
d protein-free chondroitin sulfate, keratan sulfate, and possibly some
dermatan sulfate glycosaminoglycans. The other, more prominent, peak
consisted of dermatan sulfate proteoglycans. This peak material was po
oled, and applied to a 4-15% SDS-gel. The material was separated into
two major bands, which represented biglycan and decorin. They decrease
d to less than half their day-0 value, in the cultured control. In the
loaded cartilage, biglycan synthesis remained constant while decorin
synthesis increased. These findings suggest that biglycan and decorin
are involved in the adaptation of articular cartilage to variations in
loading regime.