Effects of crotalphine on aggregating rat brain cell cultures

Abstract

Crotalphine is a 14-mer peptide isolated from the venom of Crotalus durissus terrificus "rattlesnake" that triggers long-lasting antinociception (3-5 days) mediated by kappa-opioid receptor (acute pain models) and kappa and delta-opioid receptor (chronic pain models). Crotalphine induces the activation of kappa-opioid and CB2 cannabinoid receptors with local release of dynorphin A as observed in paw tissues. Activation of kappa-opioid receptors depends on the activation of peripheral CB2 cannabinoid receptors. In PGE2-sensitized rats, crotalphine increases the activation of mitogen-activated protein kinases (MAPK) this process being dependent of the protein kinanes C ¾ (PKC ¾) activation. On the other hand, studies performed with resident and LPS-activated peritoneal macrophages have indicated that crotalphine inhibited phagocytosis, the release of H2O2 and the production of nitric oxide. Also, crotalphine increases the secretion of IL-1², modulates the secretion of IL-6 and inhibited the secretion of TNF±.Aggregating brain cell cultures are free-floating three dimensional primary cell cultures from embryonic rat brain cells which display the same cell types found in this organ such as neural stem cells, neural progenitor cells, mature neurons, glial cells (including astrocytes, oligodendrocytes and microglial cells), retain the ability to undergo cell-to-cell interactions and histotypic maturation during the time in culture (up to several months). Due to these features, the aggregating brain cell cultures have been used successfully in the evaluation of acute and subchronical neurotoxicity, demyelination, hypoglycemic and ischemia-related pathogenic processes, in neuroinflammation and neurodegenerative models.Recent studies indicate that CB2 cannabinoid receptors participate in the neuroprotective activity of cannabinoids through its anti-inflammatory actions.The aim of the present study is to evaluate the effect of crotalphine on aggregating brain cell cultures investigating its cell-type specific effect and analyzing whether crotalphine may have an anti-inflammatory potential and may prevent the demyelination induced by IFN-³ and LPS and may promote the re-myelination after this process. (AU)