Isolation, purification, and biological activities of ray cartilage glycosaminoglycans / 中草药

ABSTRACT

Objective To explore the methods of extraction, isolation, purification, and biological activities of ray cartilage glycosaminoglycans (RCG). Methods RCG was purified by guanidine hydrochlorid extraction, acetone fractional precipitation, ultrafiltration, and Sephadex column chromatography. The purity and molecular mass of RCG were measured by means of HPLC. The model of mouse with Lewis lung carcinoma was made, the experimental mice were randomly divided into normal saline group, RCG (500, 250, and 125 mg/kg) groups, and CTX (60 mg/kg) group. Tumor growth states of mice were observed, tumor growth curve was described, inhibitory rates of primary tumor and number of lung metastasis focus were measured; microvessel density (MVD) was quantitated by immunohistochemistry using monoclonal antibodies of CD31; the expression of vascular endothelial growth factor (VEGF) mRNA was determined with RT-PCR. Results Using HPLC, a single glycosaminoglycans with molecular mass 9.7?104 was collected and its purity exceeded ninty-nine percent. Tumor growth curves in RCG groups were smooth compared with saline group. There were significant differences of inhibitory rates of primary tumor, number of lung metastasis focus and MVD between RCG groups and saline group. VEGF mRNA expression levels in RCG groups were reduced significantly compared with saline group. Conclusion RCG could effectively inhibit the growth and metastasis of primary Lewis lung carcinoma in C57BL/6 mouse and angiogenesis.