Damon D H, D'Amore P A, Wagner J A
Department of Biological Chemistry and Molecular Pharmacology, Dana Farber Cancer Institute, Boston, Massachusetts 02115.
J Cell Physiol. 1988 May;135(2):293-300. doi: 10.1002/jcp.1041350217.
Glycosaminoglycans (GAGs), localized on the surfaces of cells and in the basement membrane, modulate the growth and differentiation of many cell types. Recent studies have shown that heparin, a GAG found in mast cells, potentiates the ability of acidic fibroblast growth factor (aFGF) to induce neurite outgrowth in pheochromocytoma (PC12) cells. We examined the effect of a variety of GAGs on aFGF, basic fibroblast growth factor (bFGF), and nerve growth factor (NGF)-induced neurite outgrowth in PC12 cells. The effects observed were dependent upon the specific GAG, the concentration of the GAG, and the growth factor. Heparin potentiated aFGF-induced neurite outgrowth in a concentration-dependent fashion; potentiation increased with increasing heparin concentrations of 0.01-100 micrograms/ml. At concentrations greater than 100 micrograms/ml, heparin potentiation decreased. The maximally active concentration of heparin (100 micrograms/ml) increased the potency of aFGF 102-fold. Increasing concentrations of heparan sulfate, dermatan sulfate, and chondroitin sulfate correlated with increasing aFGF potentiation. The maximally active concentrations of heparan sulfate (100 micrograms/ml), dermatan sulfate (10 mg/ml), and chondroitin sulfate (1 mg/ml) increased the activity of aFGF 11-, 110-, and 11-fold, respectively. Hyaluronic acid did not affect the neurite outgrowth-promoting activity of aFGF. Heparin also altered the activity of bFGF; increasing concentrations of heparin (0.01-1 micrograms/ml) correlated with increased potentiation. At concentrations greater than 1 microgram/ml, heparin concentration was inversely correlated with potentiation. Chondroitin sulfate only increased the percentage of neurite-bearing cells at concentrations greater than 10 micrograms/ml. Maximally active concentrations of heparin (1 microgram/ml) and chondroitin sulfate (1 mg/ml) increased the potency of bFGF 5-fold. The highest concentration of heparan sulfate studied (1 mg/ml) inhibited the activity of bFGF. Dermatan sulfate and hyaluronic acid (0.01-1000 micrograms/ml) had no effect on bFGF activity. Heparan sulfate and chondroitin sulfate showed concentration-dependent potentiation of NGF; maximally active concentrations of heparan sulfate (100 micrograms/ml) and chondroitin sulfate (1 mg/ml) increased the potency of NGF 3-fold, whereas heparin, dermatan sulfate and hyaluronic acid had no effect. None of the GAGs had any effect on PC12 neurite outgrowth when added alone. The specificity of the activity of the GAGs was verified by selective enzyme degradation.(ABSTRACT TRUNCATED AT 400 WORDS)
糖胺聚糖（GAGs）定位于细胞表面和基底膜，可调节多种细胞类型的生长和分化。最近的研究表明，肝素这种存在于肥大细胞中的GAG，可增强酸性成纤维细胞生长因子（aFGF）诱导嗜铬细胞瘤（PC12）细胞神经突生长的能力。我们研究了多种GAGs对PC12细胞中aFGF、碱性成纤维细胞生长因子（bFGF）和神经生长因子（NGF）诱导的神经突生长的影响。观察到的效应取决于特定的GAG、GAG的浓度以及生长因子。肝素以浓度依赖的方式增强aFGF诱导的神经突生长；随着肝素浓度在0.01 - 100微克/毫升范围内增加，增强作用也增加。在浓度大于100微克/毫升时，肝素的增强作用减弱。肝素的最大活性浓度（100微克/毫升）使aFGF的效力提高了102倍。硫酸乙酰肝素、硫酸皮肤素和硫酸软骨素浓度的增加与aFGF增强作用的增加相关。硫酸乙酰肝素（100微克/毫升）、硫酸皮肤素（10毫克/毫升）和硫酸软骨素（1毫克/毫升）的最大活性浓度分别使aFGF的活性提高了11倍、110倍和11倍。透明质酸不影响aFGF促进神经突生长的活性。肝素也改变了bFGF的活性；肝素浓度在0.01 - 1微克/毫升范围内增加与增强作用增加相关。在浓度大于1微克/毫升时，肝素浓度与增强作用呈负相关。硫酸软骨素仅在浓度大于10微克/毫升时增加了有神经突细胞的百分比。肝素（1微克/毫升）和硫酸软骨素（1毫克/毫升）的最大活性浓度使bFGF的效力提高了5倍。所研究的硫酸乙酰肝素的最高浓度（1毫克/毫升）抑制了bFGF的活性。硫酸皮肤素和透明质酸（0.01 - 1000微克/毫升）对bFGF活性无影响。硫酸乙酰肝素和硫酸软骨素对NGF表现出浓度依赖性增强作用；硫酸乙酰肝素（100微克/毫升）和硫酸软骨素（1毫克/毫升）的最大活性浓度使NGF的效力提高了3倍，而肝素、硫酸皮肤素和透明质酸则无影响。单独添加时，这些GAGs对PC12神经突生长均无任何影响。通过选择性酶降解验证了GAGs活性的特异性。（摘要截短至400字）
