Electroacupuncture stimulating Zhongji(CV3),Guanyuan(CV4),and bilateral Dahe(KI12)attenuates inflammation in rats with chronic nonbacterial prostatitis induced by estradiol through inhibiting toll-like receptor 4 pathway

OBJECTIVE:To investigate the anti-inflammatory effect of electroacupuncture(EA)on chronic prostatitis/chronic pelvic pain syndrome(CP/CPPS),also known as chronic nonbacterial prostatitis(CNP),and explore its underlying mechanism.METHODS:A CNP rat was established by surgical castration combined with 17-βestradiol injection in male Sprague-Dawley rats for thirty consecutive days.The CNP rats received EA treatment once a day for eight days.Chronic pelvic pain was evaluated by mechanical withdrawal threshold measurement.The histological change was assessed by hematoxylin-eosin staining.The inflammatory cytokines in prostates were determined by enzyme-linked immunosorbent assays.The expressions of toll-like receptor 4(TLR4),myeloid differentiation factor 88(MyD88),inhibitors of kappa-B alpha(IκBα),and nuclear factor-kappa B(NF-κB)were detected by Western blotting.The nuclear translocation of NF-κB and the location of TLR4 were observed with immunofluorescence staining.RESULTS:The results showed that EA decreased the prostate index,upregulated the mechanical withdrawal threshold,restored the histomorphology of the prostate,reduced the inflammatory factor levels,inhibited NF-κB p65 nuclear translocation,and downregulated the expression levels of critical proteins involved in the TLR4/NF-κB signaling pathway in prostates.CONCLUSIONS:Our findings suggested that EA could relieve pelvic pain and attenuate prostatic inflammation in estradiol-induced CNP rats.The underlying mechanism may be related to the inhibition of the TLR4/NF-κB signaling pathway.