Sakuda H, Nakashima Y, Kuriyama S, Sueishi K
First Department of Pathology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Am J Pathol. 1992 Dec;141(6):1507-16.
Conditioned media (CM) harvested from bovine smooth muscle cells (SMCs) of aortic media cultured under hypoxic conditions remarkably enhanced angiogenesis in vitro, that is, the tube formation of bovine capillary endothelial cells (BCEs) cultured on type I collagen gels. The extent of in vitro angiogenesis was assessed by the total length of tube structures formed by BCEs per area measured quantitatively with an image analyzer. The tube formation in CM obtained from the cultivation of SMCs at 1% O2 for 24 hours was enhanced by about 1.5 times and 3.4 times as compared with those at 5% O2 and 20% O2, respectively. This tube-forming activity was abrogated by the pretreatment of CM with anti-transforming growth factor (TGF)-beta 1 IgG, but not by anti-basic fibroblast growth factor IgG. The SMC-CM obtained from hypoxic cultivation (1% O2 for 24 hours) inhibited [3H] thymidine incorporation by BCEs, SMCs, and fibroblasts more than about 20% of control. Anti-TGF-beta 1 IgG thus significantly reduced the inhibitory effect of hypoxic SMC-CM on DNA synthesis of these cells. These results suggest that SMCs in a hypoxic state release active in vitro angiogenic factors into CM, and active TGF-beta 1 is closely related to the in vitro angiogenic enhancement of media conditioned by SMCs cultured in a hypoxic state.
从在低氧条件下培养的主动脉中膜牛平滑肌细胞（SMC）收获的条件培养基（CM），在体外显著增强了血管生成，即增强了在I型胶原凝胶上培养的牛毛细血管内皮细胞（BCE）的管形成。通过用图像分析仪定量测量每单位面积BCE形成的管结构的总长度来评估体外血管生成的程度。与在5% O2和20% O2条件下培养的SMC所获得的CM相比，在1% O2条件下培养24小时的SMC所获得的CM中的管形成分别增强了约1.5倍和3.4倍。用抗转化生长因子（TGF）-β1 IgG预处理CM可消除这种管形成活性，但抗碱性成纤维细胞生长因子IgG则不能。从低氧培养（1% O2，24小时）获得的SMC-CM抑制BCE、SMC和成纤维细胞的[3H]胸苷掺入，比对照多约20%以上。因此，抗TGF-β1 IgG显著降低了低氧SMC-CM对这些细胞DNA合成的抑制作用。这些结果表明，低氧状态下的SMC向CM中释放具有活性的体外血管生成因子，并且活性TGF-β1与低氧培养的SMC所条件化的培养基的体外血管生成增强密切相关。
