[Effect of electroacupuncture stimulation of "Baihui" (GV 20) and " Yongquan" (KI 1) on expression of hippocampal amyloid-β and low density lipoprotein receptor-related protein-1 in APP/PS 1 transgenic mice].

OBJECTIVE

To observe the effect of electroacupuncture (EA) treatment on the level of hippocampal amyloid-beta peptide (Aβ) and its key transport receptor low density lipoprotein receptor-related protein-1 (LRP 1) in APP/PS 1 transgenic mice so as to explore its mechanism underlying improvement of Alzheimer's disease (AD).

METHODS

Twenty-four male APP/PS 1 transgenic mice were equally and randomly divided into model group and EA treatment group, and 12 C 57 BL/6 mice were used as the normal control group. EA (1 Hz/50 Hz, 0.3 mA) was applied to "Baihui" (GV 20) and "Yongquan" (KI 1) for 15 min, once every other day for 6 weeks. The learning-memory ability was detected by using Morris water maze testing, left hippocampal Aβ 1-40 and Aβ 1-42 contents were assayed by ELISA, and right hippocampal LRP 1 expression was detected using Western blot (WB).

RESULTS

Results of Morris water maze test showed no significant differences among the three groups in the escape latency, the times of the platform-site crossovers, the time spent in the target platform quadrant (P>0.05). Compared with the model group, the moderately increased escape latency had a decreasing tendency in the EA treatment group. ELISA assaying showed that hippocampal Aβ 1-42, Aβ 1-40, and ratio of Aβ 1-42/Aβ 1-40 of the model group were significantly higher than those of the normal control group (P<0.01). After EA intervention, the increased Aβ 1-42 , Aβ 1-40, and ratio of Aβ 1-42/Aβ 1-40 were remarkably down-regulated in the EA treatment group (P<0.01). WB detection displayed that the right hippocampal LRP 1 expression level of the model group was markedly lower than that of the normal control group (P<0.05). After EA treatment, LRP 1 expression level was moderately up-regulated but without significant difference between the model and EA treatment groups (P>0.05).

CONCLUSION

EA intervention can lower the level of hippocampal Aβ in APP/PS 1 transgenic mice, but its effects on Aβ transport receptor LRP 1 expression and learning-memory ability need being confirmed further.