[Differentiation of rat bone marrow stromal cells into neural cells induced by hypoxic-ischemic brain tissue extracts in neonate rats].

Objective: To investigate the effect of brain tissue extracts in neonate rats with hypoxic-ischemic brain damage (HIBD) on the differentiation of bone marrow stromal cells (BMSCs) into neural cells.

Methods: Fifteen 7-day-old neonate rats were induced HIBD by left carotid artery ligation and hypoxia exposure, and another 15-day-old neonate rats were served as normal rats. The left and right brain tissue extracts of the normal and HIBD rats were prepared 24 h after the HIBD (8-day old), 72 h after the HIBD (10-day old), and 7 d after the HIBD (14-day old), respectively (n=5). The rat BMSCs of passage 3-5 were cultured in the medium with or without previous brain tissue extracts. The expressions of neuron specific enolase (NSE), glial fibrillary acidic protein (GFAP) and O(4) marked oligodendrocyte were detected after 3 days by immunocytochemistry.

Results: The expressions of NSE, GFAP and O(4) of BMSCs cultured in the medium with left or right brain tissue extracts of different day old normal rats were higher than those of BMSCs cultured without the extracts, respectively (P<0.01), and the expressions of NSE, GFAP and O(4) of BMSCs cultured in the medium with left brain tissue extracts of 8 day old and 10 day old HIBD rats were higher than those of BMSCs cultured with right brain tissue extracts of the same day HIBD rats and BMSCs cultured with left or right brain tissue extracts of the same day normal rats (P<0.01 or P<0.05). The expressions of NSE, GFAP and O(4) of BMSCs cultured in the medium with left brain tissue extracts of 8-day-old HIBD rats were higher than those of BMSCs cultured with left brain tissue extracts of 10-day-old and 14-day-old HIBD rats (P<0.01 or P<0.05).

Conclusion: The brain tissue extracts of normal and HIBD rats can induce BMSCS into neural cells, and the damaged brain tissue extracts of 8-day-old HIBD rats is the best inductor.