Effects of Ginkgo biloba extract on the proliferation of vascular smooth muscle cells in vitro and on intimal thickening and interleukin-1beta expression after balloon injury in cholesterol-fed rabbits in vivo.
Restenosis may develop in response to cytokine activation and smooth muscle cell proliferation. Ginkgo biloba extract (EGb) has been used to treat cardiovascular and cerebrovascular diseases. In the present study, the effects of EGb on the growth of cultured vascular smooth muscle cells (VSMC), as well as on the expression of interleukin-1beta (IL-1beta) and the intimal response in balloon-injured arteries of cholesterol-fed rabbits, were investigated. Using bromodeoxyuridine incorporation as an index of cell proliferation, EGb was found to inhibit serum-induced mitogenesis of cultured rat aorta VSMC in a dose-dependent manner. In vivo, EGb and probucol ( positive control) reduced the atheroma area in thoracic aortas of male New Zealand white rabbits fed a 2% cholesterol diet for 6 weeks with balloon denudation of the abdominal aorta being performed at the end of the third week. Intimal hyperplasia, expressed as the intimal/medial area ratio, in the abdominal aortas was significantly inhibited in the both the EGb group (0.61 +/- 0.06) and the probucol group (0.55 +/- 0.03) compared to the C group (0.87 +/- 0.02). In the balloon-injured abdominal aorta, both EGb and probucol significantly reduced IL-1beta mRNA and protein expression and the percentage of proliferating cells. The inhibitory effects of EGb on the intimal response might be attributed to its antioxidant capacity. EGb may have therapeutic potential for the prevention of restenosis after angioplasty.
Lin
Shing-Jong
SJ
Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.
Yang
Tzu-Hsuan
TH
Chen
Yung-Hsiang
YH
Chen
Jaw-Wen
JW
Kwok
Ching-Fai
CF
Shiao
Ming-Shi
MS
Chen
Yuh-Lien
YL
D000800:Angioplasty, Balloon / Q000009:adverse effects*; D000818:Animals; D000924:Anticholesteremic Agents / Q000494:pharmacology; D001012:Aorta, Abdominal / Q000187:drug effects / Q000293:injuries / Q000473:pathology; D001013:Aorta, Thoracic / Q000187:drug effects / Q000473:pathology; D001161:Arteriosclerosis / Q000188:drug therapy / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D002784:Cholesterol / Q000494:pharmacology*; D003300:Copper / Q000494:pharmacology; D004195:Disease Models, Animal; D020441:Ginkgo biloba; D007375:Interleukin-1 / Q000235:genetics / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000187:drug effects / Q000378:metabolism; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology*; D011341:Probucol / Q000494:pharmacology; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D017539:Tunica Intima / Q000187:drug effects* / Q000293:injuries / Q000473:pathology
D000924:Anticholesteremic Agents; D007375:Interleukin-1; D008077:Lipoproteins, LDL; D010936:Plant Extracts; D003300:Copper; D002784:Cholesterol; D011341:Probucol