Analgesic and anti-inflammatory activities of 80% methanol root extract of Jasminum abyssinicum Hochst. ex. Dc. (Oleaceae) in mice

BACKGROUND

Pain and inflammation are associated with the pathophysiology of various clinical conditions. Most analgesic and anti-inflammatory drugs available in the market present a wide range of problems. The current study was aimed at investigating the analgesic and anti-inflammatory activity of 80% methanol extract of J. abyssinicum root.

METHODS

The analgesic activity was determined using tail-flick test and acetic acid induced writhing, whereas anti-inflammatory activity was determined by carrageenan induced paw edema and formalin induced pedal edema, carried out in vivo. The test group received three different doses of the extract (50mg/kg, 100mg/kg and 200mg/kg) orally. The positive control group received diclofenac (10mg/kg), aspirin (100mg/kg or 150mg/kg) or morphine (20mg/kg) orally. The negative control group received vehicle (2% Tween 80, 10ml/kg) orally. Furthermore, preliminary phytochemical screening was carried out.

RESULTS

Oral administration of J. abbysinicum 80% methanol extract (at all doses) significantly (p<0.001) inhibit pain sensation in the pain models. Similarly, the extract demonstrated anti-inflammatory effect in the inflammation models in mice. Preliminary phytochemical screening showed the presence of saponins, flavonoids, terpenoids, triterpenens and glycosides.

CONCLUSION

The data obtained from the present study indicates that the extract possessed a significant analgesic and anti-inflammatory activity, upholding the folkloric use of the plant.

Evaluation of Analgesic Activity of the Methanol Extract from the Galls of Quercus infectoria (Olivier) in Rats

The present study aims to investigate the analgesic activity of the methanol extract of the galls of Quercus infectoria in rats using hot plate and tail-flick methods. The extract was administered intraperitoneally at a dose of 20 mg/kg while morphine sulfate and sodium salicylate (10 mg/kg) served as standards. The methanol extract exhibited significant analgesic activity in the tail-flick model (P < 0.05) by increasing the reaction time of the rats to 8.0 sec at 30 min after treatment in comparison to control (4.4 sec). Morphine sulfate produced a reaction time of 11.9 sec in the same test. At the peak of activity (30 min), the extract produced maximum possible analgesia (MPA) of 34.2%, whilst morphine sulfate achieved a peak MPA of 70.9%. No analgesic effects have been observed using sodium salicylate in the tail-flick model. In the same model, the extract and sodium salicylate demonstrated comparable reaction times. Tail-flick is a better method to evaluate analgesic activity as no significant results were observed for all treatments using hot plate with the exception of morphine sulfate, which showed significant results only at 45 and 60 min after treatment. In conclusion, the methanol extract of the galls of Quercus infectoria displayed analgesic activity.