Electroacupuncture downregulates TLR2/4 and pro-inflammatory cytokine expression after surgical trauma stress without adrenal glands involvement

Cumulative evidences suggest that electroacupuncture (EA) can modulate immune function, but the mechanism needs further study. In the present study, the contribution of EA on toll-like receptors 2 and 4 (TLR2/TLR4) and pro-inflammatory cytokine expression after surgical trauma stress were investigated. The mRNA level of both TLR2/4 and pro-inflammatory cytokine was measured by quantitative real-time PCR. ELISA and Western blot assay were chosen for TLR2/TLR4 protein expression and pro-inflammatory cytokine production, respectively. The results showed that surgical trauma stress increased TLR2 mRNA and TLR2/4 proteins in the spleen and augmented pro-inflammatory cytokines (e.g. IL-1beta) mRNA and protein expression in the spleen and plasma. These effects could be deteriorated by adrenalectomy (ADX). EA at "Zusanli" acupoint significantly inhibited surgical trauma-induced TLR2 mRNA and TLR2/4 protein expression in spleen and pro-inflammatory cytokine expression in the spleen and plasma. ADX, however, could not block the effect of EA. These results suggested that surgical trauma stress primes the innate immune system for enhanced TLR2 expression and pro-inflammatory cytokine production. EA inhibits TLR2/4 and pro-inflammatory cytokines to produce an anti-inflammatory effect in a surgical trauma stress model, without adrenal gland involvement.