Acupuncture for improving neuroinflammation in vascular dementia rats by regulating Th1/Th2 cells balance in peripheral blood

Abstract

To observe the effect of acupuncture on the balance of T helper (Th) 1/Th2 cells in peripheral blood, inflammatory reaction and intracerebral neuroinflammation in vascular dementia (VD) rats, and to explore the mechanism of acupuncture for improving cognitive function in VD. A total of 60 SPF Wistar rats were randomized into a normal group (n=12), a sham operation group (n=12) and an operation group (n=36). Bilateral common carotid artery occlusion was adopted to establish the VD model in rats of the operation group. The rats of successful modeling were randomized into a model group and an acupuncture group, 12 rats in each one. In the acupuncture group, Sanjiao acupuncture was applied at "Danzhong" (CV 17), "Zhongwan" (CV 12), "Qihai" (CV 6), "Xuehai" (SP 10) and "Zusanli" (ST 36), the needles were manipulated for 30 s at each acupoint, without retaining. The intervention was given once a day for 15 days, and there was 1-day rest on day 8. Morris water maze test was adopted to observe the ethology, flow cytometry was used to detect the ratio of Th1/Th2 in peripheral blood, and Luminex liquid chip technology was used to detect the levels of interleukin (IL)-4, IL-10, interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in serum and hippocampus. There were no significant differences in various indexes between the normal group and the sham operation group (P>0.05). Compared with the sham operation group, in the model group, the escape latency of hidden platform test and reversal platform test was prolonged (P<0.01), the residence time of the original platform quadrant was shortened and the number of crossing the original platform was reduced in probe test (P<0.01, P<0.05), the proportion of Th1 cells was increased, the proportion of Th2 cells was decreased and the ratio of Th1/Th2 cells was increased in peripheral blood (P<0.01), the levels of TNF-α and IFN-γ were increased, the levels of IL-4 and IL-10 were decreased in serum and hippocampus (P<0.05, P<0.01). Compared with the model group, in the acupuncture group, the escape latency of hidden platform test and reversal platform test was shortened (P<0.01), the residence time of the original platform quadrant of the probe test was prolonged (P<0.05), the proportion of Th1 cells was decreased, the proportion of Th2 cells was increased and the ratio of Th1 / Th2 cells was decreased in peripheral blood (P<0.05), the levels of TNF-α and IFN-γ were decreased, the levels of IL-4 and IL-10 were increased in serum and hippocampus (P<0.05, P<0.01). Acupuncture can improve the cognitive dysfunction and reduce the intracerebral neuroinflammation in VD rats, its mechanism may relate to the regulation of Th1/Th2 cells balance and reduce the inflammatory reaction in peripheral blood.