Disulfiram Improves Fat Graft Retention by Modulating Macrophage Polarization With Inhibition of NLRP3 Inflammasome-Mediated Pyroptosis

Abstract

Background Macrophage-mediated inflammatory response in the early post-grafting period restricts fat graft retention. Pyroptosis is a novel type of programmed cell death that extensively participates in inflammatory pathologies. Objectives This study sought to determine whether macrophage pyroptosis is activated during the inflammatory phase after fat grafting and to investigate the efficacy of a pyroptosis inhibitor, disulfiram (DSF) in fat graft retention. Methods We established a C57BL/6 mice fat grafting model and then analyzed macrophage pyroptosis. DSF (50 mg/kg, every other day) was intraperitoneally injected started from 1 h prior to fat grafting and continued for 14 days. An in vitro co-culture system was established in which mouse RAW264.7 macrophages were co-cultured with apoptotic adipocytes to further validate the findings of the in vivo studies and to explore the underlying mechanisms. Results Here we reported that macrophage pyroptosis was activated in both fat grafts and in vitro co-culture models. DSF was found to be a potent pyroptosis inhibitor to promote M2 macrophage polarization. In addition, DSF was demonstrated to enhance vascularization and graft retention. Conclusions Our results suggested that pyroptosis plays a crucial role in the inflammatory cascade within fat grafts. DSF, being a clinically available drug could be translated into a clinically effective drug for improving fat graft survival via inhibiting macrophage pyroptosis, thereby inducing M2 macrophage polarization and promoting neovascularization.