Immunoregulatory role of neuropeptides

New discoveries of a feedback loop linking the brain to the immune system and the immune system to the brain, often referred to as the “mind-body” relationships, are beginning to unfold the cellular and molecular bases of our ancient philosophy that all human diseases were simply a matter of mental attitudes (brain-derived) and resistance to environment (immunity-related). While the mind is represented by our brain, the immune system possibly serves as a sensory organ or “mobile brain” that belongs in the body [1–4]. Accumulating evidence suggests that there is a reciprocal structural-functional relationship between immune system and nervous system which includes both the central nervous system (CNS) and the peripheral nervous system (PNS). This unique relationship fundamentally implies that brain mechanisms may regulate immune responses and, conversely, that the immunocompetent cells may control the function of nerve cells. Such conceptualization would likely be of utmost pathophysiological significance because it hypothesizes the existence of dysregu-lation of neuro-immune and/or immune-neural pathways in various neuropsychiatric and possibly other diseases [1, 5, 6]. This review article will summarize the immunoregulatory role of some but not all neuropeptides found both in the CNS as well as the PNS. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.