PROLOGUE: Exploring the Phylogenetic History of Neural-immune System Interactions: An Update

Immune system participates in brain regeneration and restoration of reproduction in the earthworm Dendrobaena veneta

“…In vertebrates, PACAP protects cells within the central nervous system against stress-induced apoptosis (Vaudry et al, 2002). Although knowledge on the molecular regulation of earthworm regeneration is presently rather sparse, there are enough data available to support the general notion that there are intimate functional interactions between the neuroendocrine and innate-defense systems both in invertebrates and vertebrates (Cohen and Kinney, 2007), and that these may encompass tissue regeneration. The interplay between neural secretions and regeneration appears to be firmly established but, interestingly, in some lumbricid species the outcome of the interplay can be modulated by the state of sexual maturity of individual worms.…”

The effects of the stress response on immune function in invertebrates: An evolutionary perspective on an ancient connection

“…If neuroendocrine/immune integration is an important adaptation for survival, then it should also occur across phyla. In fact, the evidence suggests that some of the same neuroendocrine/immune connections are conserved across vertebrates and invertebrates (Ottaviani and Franceschi, 1996;Humphries and Yoshino, 2003;Cohen and Kinney, 2007;Adamo, 2008a,b). This conservation suggests that examining the neuroendocrine/immune connections of organisms with simpler physiologies may produce results with wide applicability.…”

Ghrelin stimulates phagocytosis and superoxide production in fish leukocytes

“…It is well known that GH stimulates immune functions in various vertebrates (Sakai et al 1996a, 1996b, Balm 1997, Clark 1997, Cohen & Kinney 2001, Yada & Nakanishi 2002, Yada et al 2004a, 2004b. In fish, in vivo and in vitro administration of GH enhances specific and nonspecific immune functions, such as phagocytosis by neutrophils and macrophages (Sakai et al 1996a, Balm 1997, Yada & Nakanishi 2002, Yada et al 2004a, 2004b.…”

“…Even in fish, phagocytosis by macrophages, after antigen presentation through cell-to-cell interaction with the MHC/TCR system, is necessary for production of specific antibodies (Manning 1994). Besides the energy homeostasis shown in mammals, ghrelin may, like GH, possess multiple functions in the immune system (Clark 1997, Cohen & Kinney 2001, Yada & Nakanishi 2002, Yada et al 2004b.…”