Improvement of p‐cymene antinociceptive effect by inclusion in beta‐cyclodextrin

Abstract

We demonstrate analgesic‐like property of p‐cymene (PC), a monoterpene. However, short half‐life is a limitation for PC application. Several approaches have been used to improve monoterpenes pharmaceutical properties, including the employment of drug‐delivery systems. Here we used p‐cymene/β‐cyclodextrin (β‐CD) complex and p‐cymene (PC) isolated to evaluated if the complex formulation is able to improve the antinociceptive activity of this monoterpene. Experimental protocols were approved by the Animal Care and Use Committee at UFS/Brazil (CEPA#19/11). Male mice (26–30g) were pretreated with PC/β‐CD (40 mg/kg, p.o.), PC (40 mg/kg, p.o.) or vehicle (distilled water), 0.5h before acetic acid induced abdominal writhing test and antinociceptive effect was evaluated at time: 0.5, 1, 2, 4, 8, and 16 h after treatment. We evaluated analgesic‐like effect of PC/β‐CD and PC in hot‐plate test at the same time of writhing test. The data were analyzed by ANOVA (two‐way) followed by Tukey's test (p<0.05). Our results demonstrated that acute treatment with complex PC/β‐CD produced an antinocicepitve effect (p<0.01 or p<0.001) for 8 h followed while isolated PC produced same effect for 2h. Similar results was obtained in hot‐plate test, PC/β‐CD, all doses, significantly reduces (p<0.01 or p<0.001) nociceptive behavior for 8 h while isolated PC for 1h, only higher dose. Such results were unlikely to be provoked by motor abnormality. Our results provide evidence to propose that complex with β‐CD improved analgesic effect of p‐cymene.Financial support:FAPITEC/SE/Brazil and CNPq/Brazil.