Antinociceptive activity of Hypericum caprifoliatum and Hypericum polyanthemum (Guttiferae)

Abstract

The aim of the present study was to assess the analgesic activity of the aerial parts of two Hypericum species native to Southern Brazil, H. caprifoliatum and H. polyanthemum. The antinociceptive effect of the H. polyanthemum cyclohexane extract (POL; 180 mg/kg) and of the H. caprifoliatum methanol (MET) and cyclohexane (CH) extracts (90 mg/kg) was evaluated in the hot-plate (ip and po) and writhing (po) tests using male Swiss CF1 mice weighing 22-27 g (N = 10 per group). All extracts displayed antinociceptive effects in the hot-plate test (MET ip = 48%, MET po = 39%, CH ip = 27%, CH po = 50%, POL ip = 74%, and POL po = 49% compared to control). Pretreatment with naloxone (2.5 mg/kg, sc) abolished the effects of CH and POL, and partially prevented the analgesia induced by MET administered by the ip (but not by the po) route. POL and CH (po) significantly reduced the number of writhes induced by acetic acid, while MET was ineffective in this regard. We conclude that the antinociceptive effects of the H. caprifoliatum (CH) and H. polyanthemum (POL) hexane extracts seem to be mediated by the opioid system. Moreover, the antinociceptive activity of the H. caprifoliatum MET extract seems to depend on at least two chemical substances (or groups of substances) with distinct pharmacokinetic profiles and mechanisms of action. Only the naloxone-insensitive component of MET activity showed good bioavailability following oral administration. Correspondence

Anti-inflammatory and analgesic activities of Hypericum brasiliense (Willd) standardized extract

“…This inhibition should be due to central effects, but this did not induce loss of motor coordination (Trovato et al, 2001), as our group found on the rota-rod test. An antinociceptive effect by H. caprifolatum and H. polyanthemum mediated by the opioid system had been described (Viana et al, 2003). Moreover, this activity seems to depend on at least two chemical substances, which could be fl avonoids belonging to quercetin group or dianthrones (Kumar et al, 2001).…”

The Effect of Hypericum perforatum (St. John’s Wort) on Experimental Colitis in Rat

“…HP is standardized to include hypericin (range 0.1-0.4%) and hyperforin (range 2.0-4.0%) [8]. The antidepressant [8,9], anti-inflammatory [10], antiepileptic [11], analgesic [12], and wound healing [13] effects of Hypericum species have been reported. In folk medicine in Turkey, various concentrations of HP, mainly dissolved in olive oil, are commonly used in the treatment of wounds and peptic ulcers.…”

Efeito de Hypericum caprifoliatum Cham. & Schltdl. (Guttiferae) sobre contrações em íleo isolado de cobaio induzidas por diferentes agonistas

“…Estes resultados permitem sugerir que a analgesia observada por Viana et al (2003) com o pré-tratamento com o HCP possa estar relacionada à diminuição da contração peritônio-visceral mediada pela ativação de receptores serotonérgicos. Os subtipos de receptores serotoninérgicos majoritariamente encontrados no intestino são 5-HT 3 e 5-HT 4 (Tyers;Freedman, 1992, Hegde et al, 1995Degen et al, 2001;Costall;Naylor, 2004).…”

“…O maior número de estudos científi cos publicados com as espécies brasileiras é relativo à atividade antimicrobiana in vitro (Rocha et al, 1994(Rocha et al, , 1995Schimitt et al, 2001;Dall'Agnol et al, 2003;Fenner et al, 2005); atividade alelopática (Fritz et al, 2007) e desenvolvimento embionário em ratas (Nepomuceno et al, 2005). Também foram verifi cadas atividades antiproliferativa , inibidora de monoaminoxidase (IMAO) (Rocha et al, 1994;Gnerre et al, 2001), antidepressiva (Daudt et al, 2000;Gnerre et al, 2001;Viana et al, 2005) e analgésica (Viana et al, 2003).…”