miR-221对小鼠乳腺上皮细胞增殖和泌乳功能的影响

MicroRNA（miRNA）是一类大约22个核苷酸的非编码RNA.miR-221能通过调控受体表达，引发肿瘤形成、细胞增殖和组织器官发育.本文应用脂质体转染技术，改变miR-221在小鼠乳腺上皮细胞和组织中的表达量.采用HPLC、Western 印迹、电镜技术等观察miR-221对小鼠乳腺上皮细胞和乳腺组织的影响.结果表明,miR-221沉寂后，细胞增殖能力增强（P<0.01），β酪蛋白表达增加（P>0.05），生长激素受体(GHR)表达增强（P<0.01），泌乳期乳腺组织中上皮细胞数量增加（P<0.05）,小鼠泌乳量增加（P<0.05）.结果提示，miR-221可能通过抑制靶蛋白GHR表达，进而抑制乳腺上皮细胞增殖和泌乳.

Impact of miR-221 on Mouse Mammary Epithelial Cells and Lactation

MicroRNAs (miRNAs) are a kind of non-coding small RNA of about 22 nucleotides in length. miR-221 can induce tumor generation, cell proliferation and allelotaxy through the regulation of some receptors’ expression.In this test,liposome transfection techniques were used to change the expression of miR-221 on mouse mammary epithelial cells and tissues. The effect of miR-221 on mouse mammary epithelial cells and tissues were analyzed by HPLC, Western blotting, electronic microscope, etc. It was proved that miRNA-221could probably inhibit proliferation of mouse mammary epithelial cells (P<0.01) and expression of β-casein(P>0.05).It down regulated growth hormone receptor (GHR,P<0.01) and repressed proliferation of epithelial cells of mouse lactating mammary gland (P<0.05).It could increase milk production after anti miR-221 of mammary gland(P<0.05).The results suggest that miR-221 probably inhibit mammary epithelial cells and lactation by suppressing expression of GHR.