Antinociceptive and Anti-Inflammatory Activities of the Ethanolic Extract from Synadenium umbellatum Pax. (Euphorbiaceae) Leaves and Its Fractions.

Synadenium umbellatum Pax., popularly known in Brazil as "cola-nota," "avelós," "cancerola," and "milagrosa", is a plant species used in folk medicine for the treatment of inflammation, pain, and several diseases. This study aimed to investigate the antinociceptive and anti-inflammatory activities of the ethanolic extract from Synadenium umbellatum Pax. leaves (EES) and its hexane (HF), chloroform (CF), and methanol/water (MF) fractions using the acetic acid-induced abdominal writhing test, formalin-induced paw licking test, tail flick test, croton oil-induced ear edema test, and carrageenan-induced peritonitis test. EES and MF reduced the number of acetic acid-induced abdominal writhes, while CF and HF did not. EES effect on acetic acid-induced abdominal writhing was reversed with a pretreatment with naloxone. EES reduced licking time in both phases of the formalin-induced paw licking test, but did not prolong the latency in the tail flick test. These results show that EES presented antinociceptive activity, probably involving the opioid system, anti-inflammatory activity in the croton oil-induced ear edema test, and leukocyte migration into the intraperitoneal cavity. MF also presented anti-inflammatory activity in the croton oil-induced ear edema test. In conclusion, EES and MF have antinociceptive activity involving the opioid system and anti-inflammatory activity.

Preliminary studies of gastroprotective effect of Celtis iguanaea (Jacq.) Sargent leaves (Ulmaceae).

Antiulcerogenic activity of crude ethanolic extract of Celtis iguanaea leaves (CEE) was observed with experimental models such as ethanol, indomethacin, stress and pyloric ligation-induced gastric ulcers. Results obtained from indomethacin-induced ulcer showed the hexane fraction (HF) as the active fraction of CEE. This fraction inhibits the gastric acid secretion, increasing the gastric pH, decreasing the gastric acidity and total gastric contents. Neither the CEE nor the HF alters intestinal motility, thereby excluding a cholinergic antagonist mechanism. Further studies need to be conducted with HF in order to elucidate the active principle and the pharmacological mechanism involved.

Anti-inflammatory effect of (E)-4-(3,7-dimethylocta-2,6-dienylamino)phenol, a new derivative of 4-nerolidylcatechol.

OBJECTIVES: We have investigated the anti-inflammatory and antinociceptive effects of (E)-4-(3,7-dimethylocta-2,6-dienylamino)phenol (LQFM-015), which was designed through molecular simplification strategy from 4-nerolidylcatechol. METHODS: The possible anti-inflammatory and antinociceptive effects were assayed on carrageenan-induced paw oedema and pleurisy, acetic acid-induced abdominal writhing and formalin tests in mice. KEY FINDINGS: LQFM-015 reduced the activity of PLA2 enzyme in vitro by 18%. Docking studies into the catalytic site of PLA2 were used to identify the binding mode of the LQFM-015. LQFM-015 showed a moderate antinociceptive effect, since this compound reduced the number of writhings by approximately up to 40% in the acetic acid-induced pain model; this antinociceptive activity also emerged in the second phase of the formalin-induced pain model (58% of inhibition). The anti-inflammatory action of LQFM-015 was confirmed in acute inflammation models, in which it reduced the formation of oedema to 52.78 ± 8.6 and 46.64 ± 5.2 at the second and third hour of carrageenan-induced paw oedema, respectively. Also in the carrageenan-induced pleurisy model, LQFM-015 reduced the migration of leucocytes by 26.0% and decrease myeloperoxidase activity by 50%. LQFM-015 showed different concentrations to inhibit 50% of isoenzyme cyclooxygenase activity (IC50); COX-1 IC50 = 36 µM) and COX-2 IC50 = 28 µM. CONCLUSIONS: LQFM-015 demonstrated inhibition of both PLA2 and COX enzymes; thus, the moderate antinociceptive effect of this compound could be attributed to its anti-inflammatory activity.

The anxiolytic-like effect of an essential oil derived from Spiranthera odoratissima A. St. Hil. leaves and its major component, ß-caryophyllene, in male mice.

Spiranthera odoratissima A. St. Hil. (manacá) is used in folk medicine to treat renal and hepatic diseases, stomachache, headaches and rheumatism. A central nervous system (CNS) depressant effect of the hexane fraction from the ethanolic extract of this plant has been described. ß-caryophyllene, the main component of this essential oil, is a sesquiterpene compound with anti-inflammatory properties that has been found in essential oils derived from several medicinal plants. This work is aimed to evaluate the pharmacological activity of the essential oil obtained from S. odoratissima leaves (EO) and its major component on the murine CNS; we aimed to evaluate a possible anxiolytic-like effect and the underlying mechanisms involved. In an open field test, EO (500 mg/kg) and ß-caryophyllene (50, 100 and 200 mg/kg) increased the crossing frequency (P<0.05) and, EO (250 and 500 mg/kg) and ß-caryophyllene (200 mg/kg) increased the time spent in the center (P<0.05) without altering total crossings of the open field. EO and ß-caryophyllene did not alter the number of falls in the rota-rod test (P>0.05). In the pentobarbital-induced sleep test, EO (500 mg/kg) and ß-caryophyllene (200 and 400 mg/kg) decreased the latency to sleep (P<0.05), and EO (125, 250 and 500 mg/kg) (P<0.001) and ß-caryophyllene (200 and 400 mg/kg) (P<0.05 and P<0.001) increased the sleep time. In anxiety tests, EO (500 mg/kg) and ß-caryophyllene (100 and 200 mg/kg) increased head-dipping behavior (P<0.05) in the hole-board test, entries (P<0.05) into and time spent (P<0.05) on the open arms of the elevated plus maze (EPM), and number of transitions (P<0.05) and time spent in the light compartment (P<0.05) of a light-dark box (LDB). We further investigated the mechanism of action underlying the anxiolytic-like effect of EO and ß-caryophyllene by pre-treating animals with antagonists of benzodiazepine (flumazenil) and 5-HT(1A) (NAN-190) receptors prior to evaluation using EPM and LDB. The anxiolytic-like effects of EO were significantly reduced by pre-treatment with NAN-190 (P<0.05) but not flumazenil (P>0.05). The anxiolytic-like effects of ß-caryophyllene were not blocked by either NAN-190 or flumazenil (P>0.05). In conclusion, these results suggest that the essential oil derived from S. odoratissima produces an anxiolytic-like effect without altering motor performance and that this effect is mediated by 5-HT(1A) but not via benzodiazepine receptors. In addition, the major component, ß-caryophyllene, also has an anxiolytic-like effect that may contribute to the effects of EO, but this effect does not seem to be mediated via 5-HT(1A) or benzodiazepine receptors.

Antinociceptive effect of Lafoensia pacari A. St.-Hil. independent of anti-inflammatory activity of ellagic acid.

This study was performed to determine the antinociceptive and anti-inflammatory activities of ethanolic extract of Lafoensia pacari A. St.-Hil. (PEtExt) stem bark and its fractions using various animal models such as acetic acid-induced abdominal writhing, formalin-induced pain and croton oil-induced ear edema tests. The PEtExt inhibited the acetic acid-induced abdominal writhing, reduced the pain reaction time on both phases of the formalin test and decreased the edema in a dose-dependent manner. Pre-treatment with naloxone did not reverse the antinociceptive effect. Only the ethyl acetate fraction showed antinociceptive and anti-inflammatory effects. Our results also showed that this extract contains compounds with analgesic action independent of anti-inflammatory activity.

Central activities of hydroalcoholic extract from Lafoensia pacari A. St.-Hil. stem bark / Atividades centrais do extrato de Lafoensia pacari A. St.- Hil. da casca do caule

Lafoensia pacari A. St.-Hil. can be found from Amapá to Rio Grande do Sul states, and also in Paraguay and Bolivia. It is popularly known as pacari or mangava-brava and is used to promote weight loss, as an anti-thermal or tonic, to treat gastritis, ulcers, scarring, itching, discouragement, and cancer. In the open field tests, the hydroalcoholic extract from L. pacari stem bark (HEP) decreased the number of rearings, number of invaded squares, and increased immobility time compared to control animals. In the pentobarbital-induced sleep time test, HEP decreased latency time to sleep and increased sleeping time. In the rota-rod test, no changes in the studied parameters were observed. In the elevated plus maze, HEP increased the percentage time and percentage entries in the open arms, indicating that this extract exerts an anxiolytic-like activity.

Lafoensia pacari A. St.-Hil., uma espécie vegetal presente no Brasil, do Amapá ao Rio Grande do Sul, no Paraguai e na Bolívia, é popularmente conhecida como pacari ou mangava-brava e é utilizada como emagrecedor, cicatrizante, antitérmico, tônico e para tratar gastrite, úlcera, coceira, desânimo e câncer. No teste do campo aberto, o tratamento com o extrato hidro-alcoólico de pacari (HEP) reduziu o número de rearings e o número de quadrados invadidos além de aumentar o tempo de imobilidade dos animais em relação ao controle. No sono induzido por pentobarbital sódico o tratamento com HEP causou redução na latência e aumento na duração do sono. No rota-rod, o tratamento com HEP não alterou os parâmetros observados. No teste de labirinto em cruz elevado, com o tratamento com HEP foi observado aumento do percentual do tempo de permanência e de entradas nos braços abertos, caracterizando uma atividade tipo ansiolítica.