Electro-acupuncture on Du meridian up-regulates the expression of Bcl-2 mRNA and its protein in early spinal cord injury of rats / 中国组织工程研究

ABSTRACT

BACKGROUND: It is proved that acupuncture can remarkably promote recovery of nervous function after spinal cord injury (SCI). Previous studies in our groups have been proved that electro-acupuncture can inhibit apoptosis in early period of SCI, but the mechanism is unclear yet.OBJECTIVE: To study the effect of electro-acupuncture on expressions of apoptosis inhibitory gene Bcl-2 mRNA and protein with hybridization in situ and immunohistochemistry and discuss the possible mechanism of apoptosis inhibited by electro-acupuncture in early SCI.DESIGN:Opening animal study.SETTING: Department of Anatomy, the Second Military Medical University of Chinese PLA; Shanghai Acupuncture & Moxibustion and Meridian Research Center.MATERIALSAdult male SD rats of pathogen-free aged 2-3 months were selected in this study. Bcl-2 hybridization in situ kit was provided by Wuhan Boshide Biotechnology Company Limited and Bcl-2 antibody (1200) was provided by Santa Cruz Biotechnology Company.METHODS: The experiment was completed at the Laboratory of Anatomy of the Second Military Medical University of Chinese PLA from July 2004 to December 2005. All experimental rats were randomly divided into model group, electro-acupuncture group, methylprednisolone group and sham operation group. T10 spinal cord was injuried by the modified Allen's method and treated with electro-acupuncture immediately, and then the expressions of Bcl-2 mRNA and protein were evaluated with hybridization in situ and immunohistochemistry combined with image quantitative analysis.MAIN OUTCOME MEASURES: ① Expressions of Bcl-2 mRNA and protein in early SCI; ② effect of electro-acupuncture on expressions of Bcl-2 mRNA and protein.RESULTS: The rats were supplied when they died during the experiment,and all 42 rats were involved in the final analysis. ① Moderate expression of Bcl-2 mRNA and protein was observed in the sham operation group.Expression of Bcl-2 mRNA was increased in model group at 6 hours after SCI, but expression ofBcl-2 protein was not changed. At 24 hours after SCI, both expressions of Bcl-2 mRNA and Bcl-2 protein were increased.Expression of Bcl-2 mRNA and protein was higher in electro-acupuncture group than that in mo del group (P ＜ 0.05), and there was no significant difference from that in methylprednisolone group. ② Amount of positive Bcl-2 mRNA cells was increased in electro-acupuncture group and methylprednisolone group at 6 hours after treatment, and gray value was decreased.There was significant and remarkably significant difference from those in sham operation group and model group, respectively (P ＜ 0.05-0.01). After 24-hour treatment, amount of positive Bcl-2 mRNA cells was increased in electro-acupuncture group and gray value was decreased.There was significant and remarkably significant difference from those in sham operation group and model group, respectively (P ＜ 0.05-0.01). ③ After 24-hour treatment, amount of immunohistochenistry positive Bcl-2 cells was increased in electro-acupuncture group and gray value was decreased. There was significant and remarkably significant difference from those in sham operation group and model group, respectively (P ＜ 0.05-0.01).CONCLUSION: Electro-acupuncture can up-regulate the expressions of Bcl-2 mRNA and protein so as to inhibit apoptosis in early SCI.