Nakao-Hayashi J, Ito H, Kanayasu T, Morita I, Murota S
Department of Endocrinology and Metabolism, Tokyo Metropolitan Geriatric Hospital, Japan.
Atherosclerosis. 1992 Feb;92(2-3):141-9. doi: 10.1016/0021-9150(92)90273-j.
The effects of insulin and insulin-like growth factor I (IGF-I) on migration, proliferation and tube-forming activity of endothelial cells were investigated, by using bovine carotid artery endothelial cells. Migration was assayed by a filter membrane technique and tube formation was assayed by a quantitative angiogenesis in vitro model which we have recently developed. In this model, endothelial cells are cultured between two layers of type I collagen gel and become organized into tube-like structures which mimic capillaries in vivo ultrastructurally. Insulin (50-1000 microunits/ml) and IGF-I (10-200 ng/ml) significantly stimulated migration of endothelial cells in a dose-dependent manner with a maximal stimulation of 3.0-fold at 1000 microunits/ml for insulin and 3.8-fold at 200 ng/ml for IGF-I (P less than 0.01). Insulin at concentrations up to 1000 microunits/ml and IGF-I up to 100 ng/ml did not affect proliferation of endothelial cells. When insulin or IGF-I was added in culture medium on collagen gels, tube-forming activity of endothelial cells was markedly stimulated. The specific lengths of tubes significantly increased with the increase in insulin concentration from 25 to 100 microunits/ml (P less than 0.01). At 100 microunits/ml, the stimulation was 1.77-fold (P less than 0.01). IGF-I (1-100 ng/ml) also stimulated the elongation of tubes dose-dependently with a maximal stimulation of 1.96-fold at 100 ng/ml (P less than 0.01). Thus, insulin and IGF-I at pathophysiological concentrations stimulate migration and tube-forming activity of endothelial cells, suggesting that these polypeptides may stimulate repair of endothelial injury in cases such as atherosclerosis and may act as a stimulator of angiogenesis.
采用牛颈动脉内皮细胞，研究了胰岛素和胰岛素样生长因子I（IGF-I）对内皮细胞迁移、增殖及成管活性的影响。迁移采用滤膜技术检测，成管采用我们最近建立的体外定量血管生成模型检测。在该模型中，内皮细胞培养于两层I型胶原凝胶之间，组织形成类似体内毛细血管超微结构的管状结构。胰岛素（50 - 1000微单位/毫升）和IGF-I（10 - 200纳克/毫升）以剂量依赖方式显著刺激内皮细胞迁移，胰岛素在1000微单位/毫升时最大刺激倍数为3.0倍，IGF-I在200纳克/毫升时最大刺激倍数为3.8倍（P < 0.01）。浓度高达1000微单位/毫升的胰岛素和高达100纳克/毫升的IGF-I对内皮细胞增殖无影响。当在胶原凝胶上的培养基中添加胰岛素或IGF-I时，内皮细胞的成管活性受到显著刺激。随着胰岛素浓度从25微单位/毫升增加到100微单位/毫升，管的特定长度显著增加（P < 0.01）。在100微单位/毫升时，刺激倍数为1.77倍（P < 0.01）。IGF-I（1 - 100纳克/毫升）也以剂量依赖方式刺激管的延长，在100纳克/毫升时最大刺激倍数为1.96倍（P < 0.01）。因此，病理生理浓度的胰岛素和IGF-I刺激内皮细胞迁移和成管活性，提示这些多肽可能在动脉粥样硬化等情况下刺激内皮损伤的修复，并可能作为血管生成的刺激因子。
