Anti-inflammatory neuropeptides: A new class of endogenous immunoregulatory agents

Abstract

Named Series: Neuropeptide Regulation of Immunity Anti-inflammatory neuropeptides: A new class of endogenous immunoregulatory agents Mario Delgado a, Doina Ganea b,* a Instituto de Parasitologia y Biomedicina, Consejo Superior de Investigaciones Cientificas, Granada, Spain b Temple University School of Medicine, Department of Microbiology and Immunology, 3400 N. Broad Street, Room 525A OMS, Philadelphia, PA 19140, USA a r t i c l e i n f o Article history: Received 7 June 2008 Accepted 7 June 2008 Available online 14 June 2008 Keywords: Inflammation Autoimmunity Regulatory T cells Antimicrobial peptides Tolerance Neuropeptides Hormones a b s t r a c t Resolution of inflammation and induction of immune tolerance are essential to stabilize immune homeo- stasis and to limit the occurrence of exacerbated inflammatory and autoimmune conditions. Multiple mechanisms act together to ensure the re-establishment of immune homeostasis and maintenance of tol- erance. The identification of endogenous factors that regulate these processes is crucial for the develop- ment of new therapies for inflammatory/autoimmune conditions. Neuropeptides produced during an ongoing inflammatory response emerged as endogenous anti-inflammatory agents that participate in processes leading to the resolution of inflammation and maintenance of tolerance. Anti-inflammatory neuropeptides and hormones such as vasoactive intestinal peptide, urocortin, adrenomedullin, melano- cyte stimulating hormone, ghrelin, and cortistatin have beneficial effects in a variety of experimental inflammatory and autoimmune models. Their therapeutic effect has been attributed to their capacity to downregulate innate immunity, to inhibit antigen-specific TH1-driven responses, and to generate reg- ulatory T cells. Finally, some of these neuropeptides have been identified as mediators of innate defense acting as natural antimicrobial peptides. Here we present the research findings in the neuropeptide immunoregulatory field, and examine possib