Effect of insulin and growth hormone on the synthesis of radiolabelled proteoglycans from cultured human arterial smooth-muscle cells.
The present study focuses on the pathogenesis of increased frequency of large-vessel disease in diabetes. The diabetic arterial wall displays characteristic alterations of the extracellular matrix secreted by arterial smooth-muscle cells. The effects of insulin and growth hormone on the synthesis of sulphate-labelled proteoglycans and heparan sulphate proteoglycan were studied. Proteoglycans and heparan sulphate proteoglycan were obtained from the medium and the cell layer of cultured human arterial smooth-muscle cells grown in 5% human serum. Heparan sulphate proteoglycan was quantified using ethanol precipitation combined with specific enzyme degradation. Addition of insulin (0.01, 0.05 and 0.10 mU/ml) induced a significant accumulation of 35S-labelled proteoglycans in the cell layer (2p < 0.005 and 2p < 0.001). The relative amount of cell-associated heparan sulphate proteoglycan increased during insulin stimulation (2p < 0.05). Growth hormone stimulation (5.0 and 10.0 ng/ml) caused a significant decrease in the ratio between heparan sulphate proteoglycan and proteoglycan in the cell layer (2p < 0.02 and 2p < 0.01), whereas the distribution of proteoglycans between the cell layer and the medium was unaltered.
Thøgersen
V B
VB
Department of Pathology, Aarhus University Hospital, Denmark.
Heickendorff
L
L
Ledet
T
T
D001011:Aorta / Q000166:cytology / Q000378:metabolism; D002478:Cells, Cultured; D013006:Growth Hormone / Q000494:pharmacology*; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000494:pharmacology*; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000378:metabolism*; D011509:Proteoglycans / Q000096:biosynthesis* / Q000187:drug effects / Q000378:metabolism
D013006:Growth Hormone; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate; D007328:Insulin; D011509:Proteoglycans