Molecular basis of α-tocopherol inhibition of smooth muscle cell proliferation in vitro
The molecular events responsible for the inhibition of cell proliferation by α-tocopherol have been investigated. Smooth muscle cells in vitro have been shown to be specifically inhibited by α-tocopherol with a concomitant inhibition of protein kinase C activity.β-Tocopherol was inactive, despite its similar radical scavenging activity. The point of inhibition of α-tocopherol relative to the cell cycle was localized in the late G1 phase. A second effect of α-tocopherol observed with smooth muscle cells was the stimulation of protein kinase C biosynthesis in both the S and G2 phases of the cell cycle. The implications of these findings for the onset of arteriosclerosis are discussed.
KeywordsSmooth Muscle Cell Vascular Smooth Muscle Cell Smooth Muscle Cell Proliferation Arterial Smooth Muscle Cell Liquid Scintillation Analyzer
fetal calf serum
plateletderived growth factor
protein kinase C
vascular smooth muscle cells.
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