Involvement of the PKA pathway and inhibition of voltage gated Ca2+ channels in antihyperalgesic activity of Lippia grata/β-cyclodextrin

Publication date: Available online 22 October 2019Source: Life SciencesAuthor(s): Pollyana S. Siqueira-Lima, Jullyana S.S. Quintans, Luana Heimfarth, Fabiolla R.S. Passos, Erik W.M. Pereira, Marilia M. Rezende, José E.R. Menezes-Filho, Rosana S.S. Barreto, Henrique D.M. Coutinho, Adriano A.S. Araújo, Aline S. Medrado, Ligia A. Naves, Horácio F. Bomfim, Angélica M. Lucchese, Sathiyabama Rajiv Gandhi, Lucindo J. Quintans-JúniorAbstractNeuropathic pain (NP) is a difficult condition to treat because of the modest efficacy of available drugs. New treatments are required. In the study we aimed to investigate the effects of the essential oil from Lippia grata alone or complexed in β-cyclodextrin (LG or LG-βCD) on persistent inflammatory and neuropathic pain in a mouse model. We also investigated Ca2+ currents in rat dorsal root ganglion (DRG) neurons. Male Swiss mice were treated with LG or LG/β-CD (24 mg/kg, i.g.) and their effect was evaluated using an acute inflammatory pleurisy model and nociception triggered by intraplantar injection of an agonist of the TRPs channels. We also tested their effect in chronic pain models: injection of Freund's Complete Adjuvant and partial sciatic nerve ligation (PSNL). In the pleurisy model, LG reduced the number of leukocytes and the levels of TNF-α and IL-1β. It also inhibited cinnamaldehyde and menthol-induced nociceptive behavior. The pain threshold in mechanical and thermal hyperalgesia was increased and paw edema was decreased ...
Source: Life Sciences - Category: Biology Source Type: research