不同尿酸浓度对人骨髓间充质干细胞成神经分化的影响

背景：尿酸作为一种内源性的抗氧化剂，其抗氧化、抗 DNA 损害作用及发挥神经元保护作用近年受到关注。 目的：观察不同浓度尿酸对骨髓间充质干细胞成神经分化的影响。方法：体外分离、纯化、培养骨髓间充质干细胞，观察细胞形态，取扩增3代的骨髓间充质干细胞，分别用含0（对照组）、0.2，0.4，0.8 mmol/L浓度尿酸的预诱导液诱导24 h，再用含0（对照组）、0.2，0.4，0.8 mmol/L浓度尿酸的诱导液诱导1 h后行尼氏体染色，2 h后，用免疫组织化学法检测细胞内巢蛋白、神经元特异性烯醇化酶的表达。 结果与结论：骨髓间充质干细胞经诱导后，细胞胞体收缩，形成突起并形成连接。细胞胞质中存在蓝色颗粒状的尼氏体，含不同浓度尿酸的诱导组神经元特异性烯醇化酶阳性率均较对照组明显升高（P ＜0.05），而且随着尿酸浓度增加，神经元特异性烯醇化酶阳性表达率逐渐增加（P ＜0.05）。含不同浓度尿酸的诱导组巢蛋白阳性表达率较对照组降低（P＜0.05），诱导4 h后，细胞脱落明显。在体外一定时间内，尿酸能够促进骨髓间充质干细胞向神经元样细胞的分化，且具有一定的浓度依赖性。

Effect of different concentrations of uric acid on the neural differentiation of human bone marrow mesenchymal stem cells

BACKGROUND：Uric acid as an endogenous antioxidant has garnered increasing attentions because of its anti-oxidation, anti-DNA damage and neuroprotective effects. OBJECTIVE：To observe the effect of uric acid at different concentrations on the neural differentiation of bone marrow mesenchymal stem cells. METHODS：Bone marrow mesenchymal stem cells were isolated, purified and cultured in vitro. The morphology change was observed. The third passages of bone marrow mesenchymal stem cells were induced to differentiate to neuron-like cells by induced liquid containing four different concentrations of uric acid （0 mmol/L as control group, 0.2 mmol/L, 0.4 mmol/L, 0.8 mmol/L） for 24 hours. Then, after second intervention for 1 hour, cells were detected by Nissl staining and specific markers were detected by immunohistochemistry method. RESULTS AND CONCLUSION：After induction, the cellbody shrank, forming processes and connections. Nissl body was found in the cytoplasm. The positive rates of neuron-specific enolase were significantly higher in uric acid groups of different concentrations compared to the control group （P〈0.05）;moreover, the positive rates of neuron-specific enolase were increased as the increase in concentrations of uric acid （P〈0.05）. The positive rates of Nestin were decreased in uric acid groups of different concentrations compared to the control group （P〈0.05）. After 4 hours of induction, cells fel off significantly. In a certain period of time, uric acid can promote differentiation of bone marrow mesenchymal stem cells into neuron-like cells in a certain concentration-dependent manner in vitro.