Plants with central analgesic activity

Abstract:The present study investigated the antinociceptive effects of Ocimum basilicum L. (Lamiaceae) leaf essential oil (LEO) and (-)-linalool (LIN) in formalin (2%)-, glutamate (25 μM)-and capsaicin (2.5 µg)-induced orofacial nociception models in mice. The involvement of these substances was further evaluated on the neuronal excitability of the hippocampal dentate gyrus. Male mice (n=8/group) were pretreated separately with LEO and by LIN (50, 100, and 200 mg/kg, i.p.), morphine (5 mg/kg, i.p.) and vehicle (saline + Tween 80 0.2%), before injection of nociceptive agent into the right upper lip (perinasal area). The LEO and LIN reduced the nociceptive face-rubbing behaviour in both phases on formalin test. LEO and LIN, at high doses, produced significantly antinociceptive effect in the capsaicin and glutamate tests. In hippocampal slices, LEO inhibited the population spike generated by stimulation of the hylus (antidromic stimulation), with an IC50 of 0.1±0.05 mg/mL. This response was reversibly blocked by lidocaine (0.5 mg/mL), a known voltage-dependent sodium channel antagonist and by LIN (0.5 mg/mL). Our results suggest that LEO and LIN modulate neurogenic and inflammatory pain in the tests of orofacial nociception induced by formalin, capsaicin and glutamate. Part of these effects may be associated with decreased peripheral and central neuronal excitability.

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Ocimum basilicum leaf essential oil and (-)-linalool reduce orofacial nociception in rodents: a behavioral and electrophysiological approach

Venâncio¹,

Marchioro²,

Estavam³

et al. 2011

“…Brazil not only has one of the world's highest levels of biodiversity but also it has a wealth of traditional knowledge accumulated by local people who have direct access to nature and to the products of biodiversity (Albuquerque et al, 2007). In this sense, information from Brazilian ethnic groups on traditional medicine have contributed to the discovery of pharmacological activities from several plant-derived agents, which have resulted in a signifi cant body of publications (Almeida et al, 2001;Sousa et al, 2004a;2005;De Sousa et al, 2006;Amaral et al, 2007;Silva et al, 2007;Volpato et al, 2008;Silva et al, 2009a;Silva et al 2009b;Morais at al., 2010). In spite of this, the current knowledge on the biodiversity of ecosystems as, for example, of the northeast region, is still very embryonic.…”

Section: Introductionmentioning

confidence: 99%

Bioactivity and potential therapeutic benefits of some medicinal plants from the Caatinga (semi-arid) vegetation of Northeast Brazil: a review of the literature

Silva¹,

Melo²,

Vasconcelos³

et al. 2012

Abstract:Medicinal plants have been used in traditional medicine for several thousand years all over the world. In this sense, information from Brazilian ethnic groups on folk medicine have contributed to the discovery of pharmacological activities from various plant-derived agents potentially leading to the innovative drugs. The Caatinga (semi-arid) vegetation is a highly threatened biome, covering a vast area in northeastern Brazil and has suffered from strong human influence for many decades. Many plants species found in the Caatinga have been widely used in folk medicine and for commercial manufacturing of phytotherapeutic products. Thus, the present review aims to disseminate to the scientific community some known species of medicinal plants found in the Caatinga that have been studied and analyzed in pharmacological scientific assays. Among the species that stood out for their local importance and multiplicity of uses were: Amburana cearensisand Zingiber officinalis L. (gengibre). The present study shows that several herbal constituents from Caatinga plants, whose pharmacological actions have been well characterized, may be relevant candidates for future and innovative therapeutic development.

“…Medicinal plants are known as an important source of new chemical substances with potential therapeutic effects (Almeida et al, 2001). Recently, essential oils extracted from various herbs and spices have been a subject of intensive research, partially due to the continuous discoveries of their multifunctional properties other than their classical roles as food additives and/or fragrances.…”

Section: Introductionmentioning

confidence: 99%

Phytochemical screening, antinociceptive and anti-inflammatory activities of Chrysopogon zizanioides essential oil

Lima¹,

Quintans‐Júnior²,

Thomazzi³

et al. 2012

Abstract:Chrysopogon zizanioides (L.) Roberty, Poaceae, is a plant widely used in northeast Brazil in folk medicine for the treatment of various pathological conditions, including infl ammatory pain. The present study evaluated the antinociceptive and antiinfl ammatory effects of C. zizanioides essential oil (EO) in rodents. EO was further characterized by GC/MS. The major components of EO were identifi ed as khusimol (19.57%), E-isovalencenol (13.24%), α-vetivone (5.25%), β-vetivone (4.87%) and hydroxy-valencene (4.64%). Following intraperitoneal injection (i.p.), EO at 50 and 100 mg/kg signifi cantly reduced the number of writhes (51.9 and 64.9%, respectively) and the number of paw licks during phase 2 (56.7 and 86.2%, respectively) of a formalin model when compared to control group animals. However, EO-treated mice were ineffective at all doses in hot-plate and rota-rod tests. The EO inhibited the carrageenan-induced leukocyte migration to the peritoneal cavity in a dose-dependent manner (34.7, 35.4, and 62.5% at doses of 25, 50 and 100 mg/kg, respectively). In the paw edema test, the EO (100 mg/kg) inhibited all three phases of the edema equally well, suggesting that the EO has a non-selective inhibitory effect on the release or actions of these mediators. Our results suggest possible antinociceptive and antiinfl ammatory effects of the EO.