A possible anti-inflammatory mechanism of ethyl acetate extracts of Teucrium stocksianum Bioss.

Teucrium stocksianum (T. stocksianum) is one of the important members of the genus Teucrium which contains numerous biologically active compounds. Traditionally, it is used for the treatment of fever, pain, as expectorant and blood purifier. Researchers are trying to discover plants origin, novel and safe remedies for the management of various ailments. The present study was aimed to determine the possible anti-inflammatory mechanism of ethyl acetate extract of T. stocksianum. Preliminary, the ethanolic extract and sub-fractions were screened for anti-inflammatory potential at doses of 100, 200 and 300 mg/kg (i.p) body weight, using carrageenan induced paw edema test in mice. In-order to determine the possible mechanism of anti-inflammatory effect, the ethyl acetate fraction was ascertained with different phlogistic agents like histamine, bradykinin, prostaglandins E2 and arachedonic acid via paw edema test in mice. The ethanolic extract and sub-fractions of T. stocksianum displayed marked to moderate anti-inflammatory activity in a carrageenan induced paw edema test in mice. Among the sub-fractions, ethyl acetate fraction (EAF) demonstrated excellent (66%) anti-inflammatory action at the highest tested dose (300 mg/kg) that reached to the maximum value at 3rd hour after carrageenan injection and remained significant (***P<0.001) till 5th hour of test sample administration. EAF revealed moderate effect against the paw edema induced by histamine (31.048%) while non-significant results (18.148%) were observed against the edema induced by bradykinin. The extract demonstrated significant (66.23-73.076%) anti-inflammatory potential against the edematogenic effect of prostaglandin E2. Moreover, the extract also significantly inhibited (51.33%) the paw edema induced by arachedonic acid. Our results suggest that the EAF has dual action and produced the anti-inflammatory effect by blocking both pathways of arachedonic acid metabolites (cyclooxygenase and lipoxygenase). Thus validating the traditional use of T. stocksianum and could provide a source of novel, effective and safe drug for the treatment of inflammation.