Analgesic, Antipyretic and Anti-Inflammatory Properties ofEuphorbia hirta

Abstract

Lyophilised aqueous extract of Euphorbia hirta L. (Euphorbiaceae) has been evaluated for analgesic, antipyretic and anti-inflammatory properties in mice and rats, in order to complete its activity profile, after the confirmation of the existence of a central depressant activity particularly expressed by a strong sedative effect, associated with anxiolytic effects. This study leads us to the conclusion that this plant extract exerts central analgesic properties. Such a dose-dependent action was obtained against chemical (writhing test) and thermic (hot plate test) stimuli, respectively, from the doses of 20 and 25 mg/kg and it was inhibited by a naloxone pretreatment, a specific morphinic antagonist compound. An antipyretic activity was obtained at the sedative doses of 100 and 400 mg/kg, on the yeast-induced hyperthermia. Finally, significant and dose-dependent anti-inflammatory effects were observed on an acute inflammatory process (carrageenan-induced edema test in rats) from the dose of 100 mg/kg. On the other hand, plant extract remained inactive on chronic processes such as Freund's adjuvant-induced rheumatoid arthritis, after a chronic treatment during fourteen days at the daily dose of 200 or 400 mg/kg; however, if inefficacy was observed on rat backpaws edema and on loss of weight, the aqueous extract reduced the inflammatory hyperalgia.

Anti-inflammatory and anti-nociceptive effects of Zeyheria montana (Bignoniaceae) ethanol extract

“…In this work, paw volume determinations were the average value of three repeated measures. Percentage of oedema development inhibition was expressed using the following equation: % oedema development inhibition = [(Vt -V0) control -(Vt -V0)treated]/ (Vt -V0) × 100, where Vt is the average paw volumes for each group and V0 average paw volumes for each group prior to treatments, according to Lanhers et al (1991).…”

Antinociceptive and Anti-inflammatory Activities of Methanol Extract of Ormosia coccinea (Aubl.) Jacks in vivo

“…We introduced a slight modification to the hot plate test described by Langers et al [14]. In a preselection test, mice were screened by placing the animals onto hot plate (Socrel ® DS-37) setting at 55 ± 0.2 °C and those who failed to lick their hind paw or jump (nociceptive responses) within 10 s were discarded.…”

“…Thirty minutes after treatment, mice were placed individually on the hot plate and the reaction time was again recorded at 0.5, 1 and 2 h after administration of different treatments. In order to minimize damage to the animal's paw, the cut-off time for latency of response was taken as 20 s [14]. The percentage of analgesic activity was calculated as Eq.…”

In vitro anti-inflammatory activity of fractionated Euphorbia hirta aqueous extract on rabbit synovial fibroblasts

“…[11,12] In addition, studies by our research group have also shown that the aqueous extract of the plant possesses antioxidant, bronchodilatory, and antimutagenic activities. [13,14] Besides, it exhibits the ability to inhibit production of matrix metalloproteinase (MMP)-13, a potent matrix degradative enzyme involved in OA that cleaves type II collagen.…”