An approximation to the interaction of deca-2E,6Z,8E-trienoic acid isobutylamide with cannabinoid CB2 receptor

Abstract

Background. Afinnin (AF: deca-2E,6Z,8E-trienoic acid isobutylamide) is the major alkamide found at the root of H. longipes and has been associated with pharmacological effects such as antimicrobial, morphogenetic, immunomodulatory, anesthesia and nociceptive. However, understanding of the precise action mechanism of this alkamide remains to be elucidated. Recent reports have shown that some alkamides bind significantly to cannabinoid receptors (CB). The aim of this work is to predict the interaction AF with classic cannabinoid CB2 receptor by comparing their putative pharmacophoretic properties with those of other alkamides. Material and methods. The comparison was done with the putative pharmacophoric features in AF and with those present in two CB2-binding alkamides (A1: dodeca-2E-4E,8Z,10Z-tetraenoic acid isobutylamide. A2: dodeca-2E,4E-dienoic acid isobutylamide). Results. Affinin affected the survival to phylogenetically distant organisms, such as, cell line, fungus and crustacean; LC50 values of 22, 30 and 34 µg/ml, respectively. Log P value calculated for the AF was 4.57. The molecular modeling analysis shows that AF hold similar pharmacophoric features these alkamides. These features include: H-bond acceptor (amide oxygen or carboxylic oxygen), H-bond donor (amide hydrogen) and several hydrophobic features. AF display equivalent molecular shape and inter-feature distances that the analyzed CB2 ligands. Also, docking studies indicate that AF not only binds to the same site that the modeled CB2 receptor ligands, but also does it with a similar binding energy at which they display. Conclusion. The results suggest that AF can bind to classic cannabinoid CB2 receptor.