血管生成素在人毛囊中的表达及其对毛发生长的影响

Expression of angiogenin in human hair follicle and its effect on hair growth

目的探讨血管生成素在人毛囊中的表达及其意义。方法分离完整的人生长期毛囊，提取总RNA，RT—PCR法检测血管生成素mRNA的表达，同时应用免疫组化法检测血管生成素蛋白在人毛囊中的表达：在此基础上，在体外培养的人毛囊中加入不同浓度的重组人血管生成素（0～200ng／mL），培养6d后测量毛囊的生长长度。利用两步酶法分离培养人毛乳头细胞，加入不同浓度的重组人血管生成素（0～200ng／mL），48h后，MTT法检测细胞增殖，流式细胞仪检测细胞周期。结果RT—PCR显示人毛囊表达血管生成素mRNA，免疫组化法发现人毛囊的毛乳头和真皮鞘表达血管生成素蛋白。25～200ng／mL重组人血管生成素呈浓度依赖性促进体外培养的人毛囊生长（P〈0．05），而12．5～200ng／mL重组人血管生成素能够明显促进体外培养的人毛乳头细胞增殖（P〈0．05）。流式细胞仪检测12．5～200ng／mL重组人血管生成素能够显著增加S期细胞比率和细胞增殖指数（P〈0．05）。结论血管生成素可能是一种促进毛发生长的因子。

Objective To investigate the expression of angiogenin in human hair follicle and evaluate its effect on hair growth. Methods Intact anagen hair follicles were isolated from human occipital scalp obtained from brain surgery. Some isolated human hair follicles were directly subjected to RT-PCR and immunohistochemical method for the detection of the mRNA expression and protein distribution of angiogenin in, respectively; some were cultured and incubated with angiogenin （0-200 ng/mL）, and the measurement of hair follicle length was performed before and after 6-day culture. Human dermal papilla cells were isolated from the remaining hair follicles, cultured, and treated with angiogenin ranging from 0 to 200 ng/mL for 48 hours, then, MTT assay was used to detect the cell proliferation, and flow cytometry to analyze the cell cycle. Results RT-PCR showed the mRNA expression of angiogenin in human hair follicles, and angiogenin protein was observed with immunohistochemistry at the hair papilla and dermal sheath. The angiogenin （25-200 ng/mL） stimulated the growth of human hair follicles in a dose-dependent manner in vitro （P 〈 0.05 ）. Also, as flow cytometry revealed, the treatment with 12.5-200 ng/mL of angiogenin significantly promoted the proliferation of human dermal papilla cells （P 〈 0.05 ）, and increased the percentage of cells in S phase as well as cell proliferation index （both P 〈 0.05）. Conclusion Angiogenin may be a novel stimulus for hair growth.