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-β estradiol 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.