P66shc in the spinal cord is an important contributor in complete Freund's adjuvant induced inflammatory pain in mice

Abstract

PurposeThe aim of this study is to investigate whether p66shc is involved in inflammatory pain and the potential molecular mechanisms of p66shc in inflammatory pain. MethodsInflammatory pain model was established by complete Freund's adjuvant (CFA) injection. Paw withdrawal latency (PWL) and paw withdrawal frequency (PWF) was recorded. The expression of spinal p66shc were determined by immunohistochemical staining, immunofluorescence staining. P66shc knockdown was performed by an adeno-associated virus (AAV) vector infusion. NLRP3 inflammasome complexes were determined by Western blot. DHE staining was used to evaluate reactive oxygen species (ROS) generation. ResultsP66Shc expression was progressively elevated in spinal cord of inflammatory pain mice, and p66Shc knockdown in vivo significantly attenuated CFA injection triggers hyperalgesia. Furthermore, knockdown of p66Shc significantly inhibited ROS production and NOD-like receptor protein 3 (NLRP3) inflammasome activation, which were reversed by a ROS donor (t-BOOH). However, post-treatment with nigericin, a agonist of NLRP3, reversed AAV-shP66shc analgesic effect. ConclusionSpinal p66shc may facilitate the development of inflammatory pain by promoting the activation of NLRP3 inflammasome through ROS.