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.

ObjectiveTo investigate the survival and differentiation of autologous bone-marrow mononuclear cell (ABM-MNCs) after transplanted to infarcted area and border area, and the effect of ABM-MNC on the cardiac function.Methods40 male big-ear Japanese rabbits were divided randomly into the transplanted group and control group with 20 animals in each group. Acute myocardial infarction model was made by ligating left anterior descending artery. 7 days later, Brdu labeled ABM-MNCs were injected into myocardium in the transplanted group, while the control rabbits were injected with saline. Six weeks later, tests of histology and immunohistochemistry were performed.ResultsViable cells labeled with Brdu can be identified in the infarcted area, and myocytes and endothelial cells labeled with Brdu can also be found in the border area, these cells demonstrated myogenic differentiation with the expression of α-actin by immunostaining. While, no cells labeled with Brdu were found in the control group. Moreover, the vessel density of the transplanted group in the borders of the infarction was higher than the control group (P<0.05), but there was no difference in infarcted area between two groups (P>0.05).At the 6 weeks after experiment, the cardiac function was improved in both groups, but there was a significant difference between two groups (P<0.05).ConclusionABM-MNCs injected into the infarcted myocardium can survive in both the infarcted and border areas, and differentiate into endothelial cells and other cells which are able to obtain the characters of myocytes, and increase the vessel density in border area, improve the cardiac function.