Pharmacological evaluation of Mallotus philippinensis (Lam.) Muell.-Arg. fruit hair extract for anti-inflammatory, analgesic and hypnotic activity

OBJECTIVE: Recently, we observed wound healing activity of 50% ethanol extract of Mallotus philippinensis Muell. Arg (MP) fruit hairs extract (MPE). In several intestinal infections, localized inflammation is of common occurrence and hence we evaluated the anti-inflammatory, analgesic and hypnotic activity of MPE in different rat experimental models. MATERIALS AND METHODS: Anti-inflammatory activity was evaluated by carrageenan (acute) and turpentine oil induced formalin (subacute) induced paw edema and while granuloma pouch (subacute) in rats. Analgesic and hypnotic activity of MPE was undertaken by tail-flick, hot-plate, and acetic acid-induced writhing tests while pentobarbitone-induced hypnotic potentiation in rats. RESULTS: MPE at a dose of 200 mg/kg at 3 h after their administration showed inhibition of formalin-induced paw edema by 41.60% (P < 0.001) and carrageenan-induced paw edema by 55.30% (P < 0.001). After 7 days of treatments, MPE showed 38.0% (P < 0.001) inhibition against formalin-induced paw edema and reduced weight of turpentine-induced granuloma pouch by 29.6% (P < 0.01) and volume of exudates by 26.1% (P < 0.01), respectively. MPE (200 mg/kg) showed dose-dependent elevation in pain threshold and peak analgesic effect at 120 min as evidenced by increased latency period in tail flick method and increased reaction time in the hot-plate test while the reduction in the number of acetic acid-induced writhes by 45.7% (P < 0.001). The pentobarbitone-induced hypnosis model showed potentiation, as defined by increased duration of sleep in treated group rats as compared to control. CONCLUSION: Thus, the study revealed MPE is effective in reducing acute and subacute inflammation and showed effective and similar analgesic activity. This seemed to be safe in the treatment of pain and inflammation.