F. J. A. Matos

Analgesic and antiinflammatory effects of chalcones isolated from Myracrodruon urundeuva allemão.

The present work showed analgesic and antiinflammatory activities from a fraction containing three dimeric chalcones (chalcone enriched fraction - CEF), isolated from the stem-bark ethyl acetate extract of Myracrodruon urundeuva Allemao (Anacardiaceae). M. urundeuva is a popular medicinal plant used widely in Northeast Brazil, mainly as a topical female genital tract antiinflammatory. We observed that the CEF (5 and 10 mg/kg body wt., i.p. or p.o.) inhibited acetic acid-induced abdominal contractions in mice. In the formalin test, the CEF (5 and 10 mg/kg body wt.) was more effective intraperitoneally and inhibited predominantly the second phase of response. Naloxone reversed this effect, indicating an involvement of the opioid system. The CEF (10 and 20 mg/kg body wt.) also increased the reaction time to thermal stimuli in the hot-plate test in mice, after i.p. but not after p.o. administration. In the carrageenan-induced paw edema test in mice, the CEF (20 and 40 mg/kg body wt.) decreased paw volume significantly, after i.p. administration 2-4 hours after carrageenan injection. The CEF (40 mg/kg body wt.) was also active orally during the same period of time. The present work is the first report on peripheral and central analgesic effects and antiinflammatory activity of natural dimeric chalcones.

Antinociceptive, anti-inflammatory and bronchodilator activities of Brazilian medicinal plants containing coumarin: a comparative study

This work studied the antinociceptive, antiinflammatory and bronchodilator activities of hydroalcoholic extracts (HAEs) from Torresea cearensis, Justicia pectoralis, Eclipta alba, Pterodon polygaliflorus and Hybanthus ipecacuanha. These plants are largely used in north-eastern Brazil for respiratory tract diseases, and have in common coumarin, one of their active principles. The antinociceptive effects of all HAEs in mice were similar, and the inhibition of the acetic acid-induced writhing was 35-55% with 200 mg/kg, p.o. At this dose, the effect ranged from 41-77% with the formalin test in mice, and all the HAEs inhibited preferentially the 2nd phase of the response. In one case (P. polygaliflorus), the effect was partially reversed by naloxone. Except for the HAE from T. cearensis (200 mg/kg, p.o.) which inhibited carrageenan-induced edema by 47%, the others presented no effect orally but showed a significant activity intraperitoneally. On the other hand, T. cearensis was not active in the dextran model, while inhibitions with the other ones were lower than 30%. The bronchodilator activities of J. pectoralis and P. polygaliflorus HAEs as determined in isolated guinea-pig trachea were the most active.

Antinociceptive effect of the essential oil from Cymbopogon citratus in mice

The essential oil (EO) from leaves of Cymbopogon citratus increased the reaction time to thermal stimuli both after oral (25 mg/kg) and intraperitoneal (25-100 mg/kg) administration. EO (50-200 mg/kg, p.o. or i.p.) strongly inhibited the acetic acid-induced writhings in mice. In the formalin test, EO (50 and 200 mg/kg, i.p.) inhibited preferentially the second phase of the response, causing inhibitions of 100 and 48% at 200 mg/kg, i.p. and 100 mg/kg, p.o., respectively. On the other hand, the opioid antagonist naloxone blocked the central antinociceptive effect of EO, suggesting that EO acts both at peripheral and central levels.

Analgesic and antiinflammatory activities of Justicia pectoralis Jacq and its main constituents: coumarin and umbelliferone

The hydroalcohol extract of J. pectoralis (EHA) and its main constituents, coumarin (CM) and umbelliferone (UMB), were studied for possible analgesic and antioedema activities on acetic acid induced writhing in mice and on the carrageenan and dextran paw oedema in rats. The EHA, CM and UMB demonstrated antinociceptive effects, and pretreatment with naloxone did not reverse the antinociception, indicating that the opioid system is not involved. On the other hand, pretreatment with Lβ‐arginine reversed the antinociception caused by UMB, suggesting the involvement of the nitric oxide system. The EHA, CM and UMB presented a significant antioedema effect in the carrageenan model but only CM decreased the rat paw volume in the dextran model, and this effect was not observed with EHA or UMB.

Analgesic and antiinflammatory effects of the tannin fraction from Myracrodruon urundeuva Fr. All.

The present work showed a significant antinociceptive activity in the tannin fraction (TF) extracted from the bark of Myracrodruon urundeuva Fr. All. This inhibitory effect was demonstrated not only against abdominal contractions but also in the formalin test in mice. In the first case, at doses of 0.1 and 1 mg/kg, i.p. the TF caused inhibitions of the order of 39.6% and 80.8%, respectively, and in the second one, inhibitions of 47.8% and 77.2% (phase I) and 59.2% and 100% (phase II), after the administration of 5 and 10 mg/kg, i.p. The antinociceptive effect was partially reverted by naloxone. The TF presented also an antioedematogenic effect in rat paw oedema induced by carrageenan as well as dextran. In the carrageenan model, significant inhibitions were seen at 2 h (29.7% and 41.7%) and 3 h (40.5% and 44.2%), after administration of 5 and 10 mg/kg, i.p. In the dextran induced oedema, the TF (10 mg/kg, p.o.) caused inhibitions of 29.2%, 42.4% and 54.5% at 2 h, 3 h and 4 h, respectively. The TF (10 and 25 mg/kg, i.p.) significantly inhibited the inflammatory events (vesical oedema and increased vascular permeability) which occur at the onset of the haemorrhagic cystitis induced by cyclophosphamide. After subcutaneous or oral administration, the TF (5–50 mg/kg) also blocked neutrophil migration induced by direct (fMLP) as well as indirect (carrageenan) stimuli.

Behavioral effects of essential oils from Lippia alba (Mill.) N.E. Brown chemotypes

This work presents behavioral effects of three chemotypes of essential oils (EO) from Lippia alba (Mill.) N.E. Brown (Verbenaceae) on elevated plus maze, open field and rota rod tests and also on rectal temperature in mice. The results showed that all three EO increased significantly not only the number and percentage of entries, but also the time and percentage of time of permanence in the open arms. Greater effects were presented by EO II (50 mg/kg, i.p.) as related to controls for all parameters studied. In the open field test, while EO I (200 mg/kg, i.p.) decreased only the number of rearing as compared to controls, EO II and III (100 and 200 mg/kg, i.p., respectively) decreased both the number of rearing and grooming as compared to controls. None of them altered the number of crossings. In the rota rod test, only EO II (200 mg/kg, i.p.) decreased the time of permanence on the bar related to controls. All three EO decreased the rectal temperature at the doses of 100 and 200 mg/kg, i.p. EO I contains citral, beta-myrcene and limonene as the main constituents, while citral and limonene are present in EO II, and carvone and limonene in EO III. Citral and beta-myrcene seem to be the main active components of EO I and II. However, carvone and limonene are also active and probably responsible for the effects observed with EO III.

Relaxant effects of the essential oil of Ocimum gratissimum on isolated ileum of the guinea pig

The effects of the essential oil of Ocimum gratissimum L. (Labiatae) (EOOG) on guinea pig ileum were studied. EOOG (0.1-1000 microg/ml) reversibly and concentration-dependently relaxed the basal tone of the ileum and reversed the tonic contractions induced by 60 mM KCl and 10 microM acetylcholine, with IC(50) values of 23.8+/-5.2, 18.6+/-4.0 and 70.0+/-4.6 microg/ml, respectively. Our results show that EOOG exerts relaxant effects on intestinal smooth muscle, consistent with the popular use of the plant to treat gastrointestinal disorders.

Antinociceptive properties of the essential oil of Ocimum gratissimum L. (Labiatae) in mice

We have investigated the antinociceptive effects of the essential oil of Ocimum gratissimum L. (Labiatae) (EOOG) in two classical models of pain in male Swiss mice (25-35 g), the writhing test and the formalin test. At doses of 30, 100 and 300 mg/kg (po), EOOG produced a dose-dependent inhibition (from 58.3 4.4 to 40.7 6.3, 36.4 3.6 and 24.6 3.6, respectively; N = 8-10, P<0.05) of acetic acid-induced writhing, causing up to a ~60% inhibition at the highest dose used, comparable to that obtained with indomethacin (10 mg/kg, po). At the same doses, EOOG predominantly inhibited the late (inflammatory) phase of the formalin-induced pain response (from 59.3 8.3 to 40.4 4.8, 23.2 2.8 and 25.3 5.5, respectively; N = 6, P<0.05), with a maximal reduction of ~60% of the control, although a significant reduction of the initial (neurogenic) phase was also observed at 300 mg/kg (from 62.5 6.07 to 37 5.9; P<0.05). On the basis of these data, we conclude that EOOG possesses interesting antinociceptive properties in the writhing and formalin tests. Due to the relatively low toxicity of EOOG, further detailed examination is strongly indicated for a better characterization of its pharmacological properties and its potential therapeutic value.

Medicinal Plants of Northeast Brazil Containing Thymol and Carvacrol - Lippia sidoides Cham. and L. gracillis H.B.K. (Verbenaceae)

Abstract Lippia sidoides Cham, and L. gracillis H.B.K. (Verbenaceae) are wild aromatic small trees or shrubs of Northeast Brazil vegetation. Chemical analysis of the oils obtained from the two plants by GC/MS revealed that L. sidoides contained thymol (73.1%), while L. gracillis contained carvacrol (47.7%) and p-cymene (19.2%) as main components.

Essential Oil of Mentha x villosa Huds. from Northeastern Brazil

Abstract An oil produced from Mentha x villosa Huds. by steam distillation of plant material collected in Fortaleza was analyzed by GC/MS and retention indices. The oil was found to be rich in piperitenone oxide (55.4%) and γ-muurolene (13.1%).