[Effect of manual acupuncture on expression of BDNF/TrkB/ERK/CREB signaling in infarcted tissue of cerebral ischemia rats].

OBJECTIVE

To observe the effect of acupuncture on the expression of cortical brain-derived neurothrophic factor (BDNF) and tyrosine kinase receptor B (TrkB) mRNAs, and phosphorylated extracellular regulated protein kinases (p-ERK) 1/2 and phosphorylated cAMP response element binding protein (p-CREB) proteins in cerebral ischemia (CI) rats, so as to explore its neuroprotective mechanism on ischemic brain tissue.

METHODS

Thirty male SD rats were randomly divided into sham-operation (control), model and acupuncture groups, with 10 rats in each group. The CI model was established by occlusion of the left middle cerebral artery (MCAO) using thread embolization method. Manual acupuncture was applied to"Baihui"(GV20),"Quchi"(LI11),"Neiguan"(PC6),"Hegu"(LI4),"Zusanli"(ST36),"Sanyinjiao"(SP6) and"Shenmai"(BL62) once daily, 6 days a week for 2 weeks. The modified neurological severity score (mNSS) including motor, sensation, balance, and neural reflex functions (0 point, normal; 18 points, maximal deficit) was used to assess the neurological impairment state. The expression levels of p-ERK 1/2 and p-CREB proteins, and BDNF and TrkB mRNAs in the ischemic cerebral cortex were measured by Western blot and real-time fluorescence quantitative PCR, respectively.

RESULTS

The mNSS was significantly increased on day 1, 7 and 14 in the model group compared with the control group (<0.01), and evidently decreased on day 14 in the acupuncture group in contrast to the model group (<0.05). The expression levels of BDNF and TrkB mRNAs, and p-ERK1, p-ERK2 and p-CREB proteins on day 7 and 14 were significantly lower in the model group than in the control group (<0.001). Following acupuncture treatment, the down-regulated expression levels of the two genes and the three proteins on day 14 were reversed (<0.001, <0.05, <0.01).

CONCLUSION

Acupuncture may promote neurological recovery in rats with cerebral ischemia, which may be related to its function in up-regulating the activities of BDNF/TrkB-ERK-CREB signaling in the cerebral cortex on the ischemic side.