Effects of a Long Term Physical Exercise on the mrna Level of BDNF in Mice after Middle Cerebral Artery Occlusion

Abstract

Backgroud: BDNF plays an important role in maintaining survival and function of neurons. Exercise may be increasing the mRNA and protein level of BDNF in hippocampus and cortex. Objective: To investigate the impact of a long-term physical training on the mRNA and protein level of BDNF after Middle Cerebral Artery Occlusion (MCAO) in mice. Design, Time and Seting: A randomized, controlled, animal experiment was performed at the department of rehabilitation medicine, Chinese PLA general hospital Materials: Twenty-six male C57 BL/6J mice (20–30g, 2-3 months old) were provided by Experimental Animal Center of Institute of Medicine, Chinese PLA general hospital. Methods: Twenty-six male C57 BL/6J mice underwent MCAO (described by Bederson JB et al) and then were divided into training group Ι (n=9), training group II (n=9) and control group (n=8). The mice of training group I were trained with voluntary running wheel for one hour daily (6 days per week) for 90 days; The mice of training group II were trained for 15 days, stopped for 30 days and retrained for 45 days after MCAO .The running wheel of control group was fixed. The mRNA level of BDNF mice brain was tested by RT-PCR method 90 days after MCAO. The design of study is completely randomized among three groups. Wilcoxon rank sum test and Kruskal-Wallis test were performed. Main Measures: Quantitation of the expression of BDNF genes is determined by RT-PCR for mRNA level techniques and Western blotting for protein level. Results: Both the mRNA and protein levels of BDNF mice brain are significantly higher in training group I and training group II than that in control group in 90 days after MCAOi¼ˆT values respectively are 5.1 and 3.9,P 0.05). Conclusion: The long term physical training can elevate the mRNA and protein levels of BDNF in mice brain after Middle Cerebral Artery Occlusion.