Cardiovascular Key Lab of Zhejiang Province, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
Acta Pharmacol Sin. 2011 Dec;32(12):1483-90. doi: 10.1038/aps.2011.141.
To investigate whether nerve growth factor (NGF) induced angiogenesis of bone marrow mesenchymal stem cells (MSCs) and the underlying mechanisms.
Bone marrow MSCs were isolated from femors or tibias of Sprague-Dawley rat, and cultured. The cells were purified after 3 to 5 passages, seeded on Matrigel-coated 24-well plates and treated with NGF. Tube formation was observed 24 h later. Tropomyosin-related kinase A (TrkA) and p75NTR gene expression was examined using PCR analysis and flow cytometry. Growth curves were determined via cell counting. Expression of VEGF and pAkt/Akt were analyzed with Western blot.
NGF (25, 50, 100 and 200 μg/L) promoted tube formation of MSCs. The tubular length reached the maximum of a 2.24-fold increase, when the cells were treated with NGF (50 μg/L). NGF (50 μg/L) significantly enhanced Akt phosphorylation. Pretreatment with the specific PI3K inhibitor LY294002 (10 μmol/L) blocked NGF-stimulated Akt phosphorylation, tube formation and angiogenesis. NGF (25-200 μg/L) did not affect the expression of TrkA and vascular endothelial growth factor (VEGF), but significantly suppressed the expression of p75NTR. NGF (50 μg/L) markedly increased the proliferation of MSCs.
NGF promoted proliferation of MSCs and activated the PI3K/Akt signaling pathway, which may be responsible for NGF induction of MSC angiogenesis.
研究神经生长因子（NGF）是否诱导骨髓间充质干细胞（MSCs）血管生成及其机制。
分离 Sprague-Dawley 大鼠股骨或胫骨骨髓间充质干细胞，培养后传代 3-5 次，接种于铺有 Matrigel 的 24 孔板，用 NGF 处理。24 h 后观察管腔形成。用 PCR 分析和流式细胞术检测原肌球蛋白相关激酶 A（TrkA）和 p75NTR 基因表达。通过细胞计数确定生长曲线。用 Western blot 分析血管内皮生长因子（VEGF）和 pAkt/Akt 的表达。
NGF（25、50、100 和 200 μg/L）促进 MSCs 管腔形成。当细胞用 NGF（50 μg/L）处理时，管状长度达到最大的 2.24 倍增加。NGF（50 μg/L）显著增强 Akt 磷酸化。用特异性 PI3K 抑制剂 LY294002（10 μmol/L）预处理可阻断 NGF 刺激的 Akt 磷酸化、管腔形成和血管生成。NGF（25-200 μg/L）不影响 TrkA 和血管内皮生长因子（VEGF）的表达，但显著抑制 p75NTR 的表达。NGF（50 μg/L）显著增加 MSCs 的增殖。
NGF 促进 MSCs 增殖并激活 PI3K/Akt 信号通路，这可能是 NGF 诱导 MSC 血管生成的原因。
