Anti-inflammatory and analgesic properties of Heracleum persicum essential oil and hydroalcoholic extract in animal models.

ETHNOPHARMACOLOGICAL RELEVANCE: Fruits of Heracleum persicum (Apiaceae) are used as pain killer in Iranian folkloric medicine.

AIMS OF STUDY: To evaluate the anti-inflammatory and analgesic effects of the hydroalcoholic extract and essential oil of the plant fruits and analyzing the essential oil.

MATERIALS AND METHODS: Essential oil and hydroalcoholic extracts of the fruits were prepared according to standard methods and the components of essential oil were identified using GC-MS method. The acetic acid-induced writhing response and formalin test were used in male mice to assess analgesic activity. For evaluation of anti-inflammatory effect, carrageenan-induced rat paw edema was used.

RESULTS: Hexyl butyrate (56.5%), octyl acetate (16.5%), hexyl 2-methylbutanoate (5.2%) and hexyl isobutyrate (3.4%) were identified as the major constituents of the oil. Oral or intraperitoneal administration of Heracleum persicum essential oil (HPEO) at doses of 50-200 mg/kg and Heracleum persicum hydroalcoholic extract (HPHE) at doses of 250 and 500 mg/kg significantly reduced acetic acid-induced abdominal constrictions. HPEO and HPHE also significantly attenuated the pain response of the second phase of formalin test. In carrageenan test HPEO at doses of 100 and 200 mg/kg and HPHE at a dose of 400 mg/kg induced a significant reduction of paw edema.

CONCLUSIONS: These results clearly show the analgesic and anti-inflammatory effects of the plant essential oil and hydroalcoholic extract. Further studies are needed to clarify the mechanism of action and the components responsible for these pharmacological effects.