Titre
A phospholipase A2-related snake venom (from Crotalus durissus terrificus) stimulates neuroendocrine and immune functions: determination of different sites of action
Type
article
Institution
UNIL/CHUV/Unisanté + institutions partenaires
Périodique
Auteur(s)
Chisari, A.
Auteure/Auteur
Spinedi, E.
Auteure/Auteur
Voirol, M. J.
Auteure/Auteur
Giovambattista, A.
Auteure/Auteur
Gaillard, R. C.
Auteure/Auteur
Liens vers les personnes
rgaillar
Liens vers les unités
ISSN
0013-7227
Statut éditorial
Publié
Date de publication
1998-02
Volume
139
Numéro
2
Première page
617
Dernière page/numéro d’article
25
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Feb
Research Support, Non-U.S. Gov't --- Old month value: Feb
Résumé
Immune neuroendocrine interactions are vital for the individual's survival in certain physiopathological conditions, such as sepsis and tissular injury. It is known that several animal venoms, such as those from different snakes, are potent neurotoxic compounds and that their main component is a specific phospholipase A type 2 (PLA2). It has been described recently that the venom from Crotalus durissus terrificus [snake venom (SV), in the present study] possesses some cytotoxic effect in different in vitro and in vivo animal models. In the present study, we investigated whether SV and its main component, PLA2 (obtained from the same source), are able to stimulate both immune and neuroendocrine functions in mice, thus characterizing this type of neurotoxic shock. For this purpose, several in vivo and in vitro designs were used to further determine the sites of action of SV-PLA2 on the hypothalamo-pituitary-adrenal (HPA) axis function and on the release of the pathognomonic cytokine, tumor necrosis factor alpha (TNF alpha), of different types of inflammatory stress. Our results indicate that SV (25 microg/animal) and PLA2 (5 microg/animal), from the same origin, stimulate the HPA and immune axes when administered (i.p.) to adult mice; both preparations were able to enhance plasma glucose, ACTH, corticosterone (B), and TNF alpha plasma levels in a time-related fashion. SV was found to activate CRH- and arginine vasopressin-ergic functions in vivo and, in vitro, SV and PLA2 induced a concentration-related (0.05-10 microg/ml) effect on the release of both neuropeptides. SV also was effective in changing anterior pituitary ACTH and adrenal B contents, also in a time-dependent fashion. Direct effects of SV and PLA2 on anterior pituitary ACTH secretion also were found to function in a concentration-related fashion (0.001-1 microg/ml), and the direct corticotropin-releasing activity of PLA2 was additive to those of CRH and arginine vasopressin; the corticotropin-releasing activity of both SV and PLA2 were partially reversed by the specific PLA2 inhibitor, manoalide. On the other hand, neither preparation was able to directly modify spontaneous and ACTH-stimulated adrenal B output. The stimulatory effect of SV and PLA2 on in vivo TNF alpha release was confirmed by in vitro experiments on peripheral mononuclear cells; in fact, both PLA2 (0.001-1 microg/ml) and SV (0.1-10 microg/ml), as well as concavalin A (1-100 microg/ml), were able to stimulate TNF alpha output in the incubation medium. Our results clearly indicate that PLA2-dependent mechanisms are responsible for several symptoms of inflammatory stress induced during neurotoxemia. In fact, we found that this particular PLA2-related SV is able to stimulate both HPA axis and immune functions during the acute phase response of the inflammatory processes.
Sujets
PID Serval
serval:BIB_1B8C0A02F752
PMID
Open Access
Oui
Date de création
2008-02-15T15:57:16.205Z
Date de création dans IRIS
2025-05-20T19:08:44Z