Apoptosis induced by 7-ketocholesterol is enhanced in smooth muscle cells derived from OLETF rats.

نویسندگان

  • Yoh Miyashita
  • Nobukiyo Koide
  • Tomokazu Oyama
  • Yoshiaki Itoh
  • Kohji Shirai
چکیده

To clarify whether an increased proliferative potential of vascular smooth muscle cells (SMC) under diabetic conditions augments the susceptibility of the cells to 7-ketocholesterol-induced apoptosis, we investigated the difference in sensitivity to 7-ketocholesterol between SMC obtained from diabetic Otsuka Long-Evans Tokushima fatty (OLETF) rats and the control Long-Evans Tokushima Otsuka (LETO) rats. The outgrowth rate from aortic wall explants and cell proliferation were higher in SMC derived from OLETF rats (OLETF-derived SMC) compared to those from LETO rats (LETO-derived SMC). When 7-ketocholesterol was added to SMC, the amount of fragmented DNA increased significantly in OLETF-derived compared to LETO-derived SMC. The amount of fragmented DNA induced by 7-ketocholesterol decreased significantly in both OLETF- and LETO-derived SMC when they were incubated without fetal bovine serum. By adding PDGF-BB to LETO-derived SMC, the amount of fragmented DNA induced by 7-ketocholesterol increased significantly. These results suggest that apoptosis of SMC induced by 7-ketocholesterol may be accelerated when SMC acquire a high proliferative potential by prolonged exposure to diabetic condition.

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عنوان ژورنال:
  • Journal of atherosclerosis and thrombosis

دوره 12 2  شماره 

صفحات  -

تاریخ انتشار 2005