Differences in Cellular Responses to Mitogens in Arterial Smooth Muscle Cells Derived From Patients With Moyamoya Disease

Abstract

Background and Purpose —Moyamoya disease is a progressive cerebrovascular occlusive disease affecting primarily children. The etiology remains unknown. We examined the chemotactic and proliferative activities of inflammatory cell products from arterial smooth muscle cells (SMCs) derived from moyamoya patients and compared them with those from control subjects. Methods —We used 12 SMC strains from moyamoya patients and eight from control subjects. SMC migration was examined in a micro chemotaxis chamber. DNA synthesis was measured by an immunoperoxidase technique. Results —Platelet-derived growth factor (PDGF)-BB markedly stimulated cell migration and DNA synthesis in control SMCs. PDGF-AA stimulated only DNA synthesis in control SMCs. In moyamoya SMCs, PDGF-AA and PDGF-BB stimulated cell migration but not DNA synthesis. Basic fibroblast growth factor had little migratory activity but stimulated DNA synthesis in moyamoya SMCs and control SMCs. Conversely, hepatocyte growth factor stimulated cell migration but not DNA synthesis in moyamoya SMCs and control SMCs. In contrast, interleukin-1β (IL-1β) significantly stimulated the migration and DNA synthesis of control SMCs, while it inhibited moyamoya SMC migration. The levels of IL-1β–induced nitric oxide production did not differ between moyamoya SMCs and control SMCs, suggesting that IL-1β inhibits the migration of moyamoya SMCs through a nitric oxide–independent pathway. Conclusions —The differences in responses to PDGF and IL-1 in moyamoya SMCs are involved in the mechanism by which intimal thickening develops in moyamoya disease.