Ocimum basilicum essential oil complexed with β‐Cyclodextrin increases fos protein expression in CNS areas and produces analgesic profile

Abstract

Ocimum basilicum leaves essential oil (LEO) is rich in monoterpenes, such as linalool and geraniol, and it have shown analgesic effects, but short half‐life and water insolubility are restraint for LEO therapeutic approaches. β‐cyclodextrin (β‐CD) has been applied to improve pharmacological profiles of essential oils or related compounds. Thus, we assessed the antihiperalgesic effect of LEO, alone, or complexed in β‐CD (LEO/β‐CD), on chronic non‐inflammatory muscle pain (an animal model for fibromyalgia) and evaluate the c‐Fos expression in the mice CNS). Mice were treated every day with either LEO/β‐CD (25, 50 or 100 mg/kg, p.o.), LEO (25 mg /kg, p.o.), tramadol (TRM 4mg /kg, i.p.) or vehicle (saline), and 60 minutes after treatment parameters were assessed. Oral treatment with LEO or LEO‐βCD, at all doses tested, produced a significant reduction of mechanical hyperalgesia (p<0.001) and they are able to significantly (p<0.05) increase Fos protein expression in nucleus raphe magnus and periaqueductal gray. Our results provide evidence suggesting that LEO and LEO/β‐CD produces analgesic effects through an activation of CNS areas, such as periaqueductal grey.Financial Support: CNPq/Brazil, CAPES/Brazil, FAPITEC/SE/Brazil and FINEP/Brazil