Abstract: Objective　To detect the promoting effect of papain on the angiogenesis of rat endothelial progenitor cells (EPCs) in vitro. Methods　The EPCs in 3rd passage were cultured with complete medium containing papain with the concentrations of 10, 50, and 100 μg/ml. After cultured for 0, 7, and 14 days, the expression levels of angiogenesis genes VEGF (vascular endothelial growth factor) and CD31 (platelet endothelial cell adhesion molecule) were detected by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). The proliferation of EPCs was detected by CCK-8 assay. The statistical method was analysis of variance. Results　After cultured for 14 days, the expression levels of VEGF and CD31 and proliferation ability of EPCs in the papain groups were significantly higher than those of the blank control group. The expression level of VEGF reached the highest when EPCs cultured with medium with 50 μg/ml of papain (3.28 times of the blank control group). The expression level of CD31 increased with the increase of papain concentration, reaching 3.66 times of the blank control group. Conclusion　Proper concentration of papain can promote the angiogenesis and proliferation of EPCs in vitro, which shows that the papain can promote the formation of vascular tissue.

Key words: Papain, EPCs, Angiogenesis

摘要： 目的　通过体外鼠细胞模型实验，检测木瓜酶在体外培养环境下对血管内皮细胞成血管向分化的促进功能。方法　采用P3代大鼠血管内皮细胞，将木瓜酶溶解于完全培养基内，按照10 μg/ml、50 μg/ml、100 μg/ml浓度配置含木瓜酶的完全培养基，与空白对照组共同培养0、7、14 d，通过逆转录聚合酶链反应（qRT-PCR）法检测成血管分化相关基因VEGF（血管内皮生长因子）、CD31（血小板-内皮细胞粘附分子）的表达水平，通过CCK-8法检测不同组细胞的增殖活力。统计学方法为方差分析。结果　经14 d培养，添加木瓜酶的细胞VEGF、CD31表达水平及增殖能力显著高于空白对照组，木瓜酶浓度达到50 μg/ml时VEGF表达水平达到最高，为空白对照组的3.28倍，CD31表达水平随着木瓜酶浓度升高而升高，最高达到空白对照组的3.66倍。结论　适宜浓度的木瓜酶能够在体外促进内皮细胞的成血管分化及增殖，表明木瓜酶对血管组织形成具有一定的促进作用。

关键词: 木瓜酶, 内皮细胞, 血管形成