Effect of hypercholesterolaemia on platelet growth factors.
Evidence from several sources suggests that important interactions occur between platelets and low-density lipoproteins. This study was undertaken to find out if diet-induced hypercholesterolaemia affects the growth factor content in circulating platelets. Minipigs were fed either normal diet supplemented with 2% cholesterol (n = 12) or normal diet alone (n = 12). After 4 months, mean platelet volume was significantly lower (P < 0.05) and monocyte count was significantly higher (P < 0.05) in the cholesterol group. Serum and intraplatelet levels of platelet-derived growth factor (BB homodimer) and transforming growth factor beta 1 were statistically unchanged after diet. Hypercholesterolaemia did not affect the proliferative effect of either serum or platelet lysates on porcine vascular smooth muscle cells and Swiss-3T3 cells in culture. A significant positive correlation between Swiss-3T3 and smooth muscle cell proliferation was present in both groups. These results suggest that the atherosclerosis-promoting effect of hypercholesterolaemia cannot be explained by its direct effect on smooth muscle cell proliferation or by changes in serum or intraplatelet concentrations of growth factors.
García-Bolao
I
I
Department of Cardiology, University Clinic and School of Medicine, Pamplona, Spain.
Merino
J
J
Martínez
A
A
Grau
A
A
Alegría
E
E
Martínez-Caro
D
D
D016475:3T3 Cells; D000818:Animals; D001772:Blood Cell Count; D001792:Blood Platelets / Q000737:chemistry*; D006937:Hypercholesterolemia / Q000097:blood*; D008297:Male; D051379:Mice; D010982:Platelet-Derived Growth Factor / Q000032:analysis*; D013552:Swine; D013556:Swine, Miniature; D016212:Transforming Growth Factor beta / Q000097:blood*
D010982:Platelet-Derived Growth Factor; D016212:Transforming Growth Factor beta