Exopolysaccharides from Klebsiella oxytoca: anti-inflammatory activity

Abstract Exopolysaccharides (EPS) produced by Klebsiella oxytoca are of environmental, pharmaceutical, and medicinal interest. However, studies about the anti-inflammatory activity of EPS produced by this microorganism still remain limited. The aim of this study was to produce, characterize, and evaluate the anti-inflammatory activity of EPS from K. oxytoca in a pleurisy model. Colorimetric analysis revealed that precipitated crude exopolysaccharides (KEPSC) and deproteinated exopolysaccharides (KEPS) present high levels of total carbohydrates (65.57% and 62.82%, respectively). Analyses of uronic acid (7.90% in KEPSC and 6.21% in KEPS) and pyruvic acid (3.01% in KEPSC and 1.68% in KEPS) confirm that the EPS are acidic. Gas chromatography-mass spectrometry analyses demonstrated that the EPS consisted of rhamnose (29.83%), glucose (11.21%), galactose (52.45%), and mannose (6.50%). The treatment of an experimental pleurisy model in rats through subcutaneous administration of 50, 100, 200, and 400 mg/kg of KEPS decreased both the volume of inflammatory exudate and the number of leukocytes recruited to the pleural cavity. The present data showed that EPS production by K. oxytoca using the method described is easy to perform and results in a good yield. In addition, we show that KEPS exhibit anti-inflammatory activity when administered subcutaneously in rats.

Anti-inflammatory, antinociceptive, and antipyretic effects of methanol extract of Cariniana rubra stem bark in animal models

Cariniana rubra Miers (Lecythidaceae), popularly known as "jequitibá-vermelho'', is a large Brazilian tree whose bark is used in infusion and decoction for the treatment of inflammatory conditions. This study aims to assess the anti-inflammatory, antinociceptive, and antipyretic effects of Cariniana rubra methanolic stem bark extract (EM Cr) using experimental animals. Anti-inflammatory activity of EM Cr was tested on carrageenan and dextran-induced rat paw edema, carrageenan-induced pleurisy in rats and acetic acid-increase vascular permeability in mice. Antinociceptive and antipyretic activities were evaluated using acetic acid-induced writhing, formalin and hot-plate tests in mice, as well as brewer's yeast-induced pyrexia in rats. The extract inhibitied carrageenan and dextran-induced edema, reduced exudate volume and leukocyte migration on the carrageenan-induced pleurisy and on the vascular permeability increase induced by acetic acid. The EM Cr inhibited nociception on the acetic acid-induced writhing and in the second phase of formalin test, and decreased rectal temperature. It was, however, inactive against thermal nociception.Phytochemical analysis with EM Cr showed the occurrence of saponins, triterpenes, sterols and phenolic compounds. Phytosterols (β-sitosterol, stigmasterol), pentacyclic triterpenes (α- and β-amyrin as a mixture), arjunolic acid, a phytosterol glycoside (sitosterol 3-O-β-D-glucopyranoside), and triterpenoid saponins (28-β-glucopyranosyl-23-O-acetyl arjunolic acid; 3-O-β-glucopyranosyl arjunolic acid and 28-O-[α-L-Rhamnopyranosyl-(1→2)-β-glucopyranosyl]-23- O-acetyl arjunolic acid) were the main identified compounds. It can be presumed that EM Cr caused their effects by inhibiting the liberation and/or action of different inflammatory mediators. These findings support the traditional use of Cariniana rubra preparations to treat inflammation.

Cariniana rubra Miers (Lecythidaceae), popularmente conhecido como "jequitibá-vermelho'', é uma árvore brasileira de grande porte, cuja casca é utilizada nas formas de infusão e decocção para o tratamento de condições inflamatórias. Os efeitos antiinflamatório, antinociceptivo e antipirético do extrato metanólico da casca do caule de Cariniana rubra (EM Cr) foram avaliados em animais experimentais. A atividade antiinflamatória do EM Cr foi testada nos modelos de edema depata induzido por carragenina e dextrana em ratos, pleurisia induzida por carragenina em ratos e permeabilidade vascular aumentada por ácido acético em ratos. As atividades antinociceptiva e antipirética foram avaliadas utilizando os modelos de nocicepções induzidos por ácido acético e formalina, placa quente em camundongos e de pirexia, pela injeção de levedura de cerveja em ratos. O extrato inibiu o edema induzido porcarragenina e dextrana, reduziu o volume de exsudato e a migração de leucócitos na pleurisia induzida por carragenina eo aumento da permeabilidade vascular induzida por ácidoacético. O EM Cr inibiu a nocicepção nas contorções induzidas por ácido acético e na segunda fase do teste de formalina e diminuiu a temperatura retal. No entanto, foi inefetivo no teste da placa quente. A análise química por via úmida deu resultados positivos para saponinas, triterpenos, esteroides e compostos fenólicos. Fitosteróis e triterpenóides pentacíclicos (β-sitosterol, estigmasterol, α and β-amirinas em mistura e ácido arjunólico) e as saponinas triterpenoidais: 3-O-β-D-glucopiranosideo de sitosterol; ácido arjunólico 28-β-glucopiranosila-23-O-acetila; ácido arjunólico 3-O-β-glucopiranosila e ácido arjunólico 28-O-[α-L-rhamnopiranosil-(1→2)-β-D-glucopiranosila]-23-O-acetila. Pode-se presumir que os efeitos do EM Cr foram causados pela inibição da liberação e/ou ação de diversos mediadores inflamatórios. Estes resultados validam o uso tradicional das preparações caseiras de Cariniana rubra para tratar a inflamação.

Analgesic and anti-inflammatory activity of the aqueous extract of Rheedia longifolia Planch & Triana

Rheedia longifolia Planch et Triana belongs to the Clusiaceae family. This plant is widely distributed in Brazil, but its chemical and pharmacological properties have not yet been studied. We report here that leaves aqueous extract of R. longifolia (LAE) shows analgesic and anti-inflammatory effects. Oral or intraperitoneal administration of this extract dose-dependently inhibited the abdominal constrictions induced by acetic acid in mice. The analgesic effect and the duration of action were similar to those observed with sodium diclofenac, a classical non-steroidal analgesic. In addition to the effect seen in the abdominal constriction model, LAE was also able to inhibit the hyperalgesia induced by lipopolysaccharide from gram-negative bacteria (LPS) in rats. We also found that R. longifolia LAE inhibited an inflammatory reaction induced by LPS in the pleural cavity of mice. Acute toxicity was evaluated in mice treated with the extract for seven days with 50 mg/kg/day. Neither death, nor alterations in weight, blood leukocyte counts or hematocrit were noted. Our results suggest that aqueous extract from R. longifolia leaves has analgesic and anti-inflammatory activity with minimal toxicity and are therefore endowed with a potential for pharmacological control of pain and inflammation.

Pharmacological study of anti-allergic activity of Syzygium cumini (L) Skeels

Myrtaceae is a plant family widely used in folk medicine and Syzygium and Eugenia are among the most important genera. We investigated the anti-allergic properties of an aqueous leaf extract of Syzygium cumini (L.) Skeels (SC). HPLC analysis revealed that hydrolyzable tannins and flavonoids are the major components of the extract. Oral administration of SC (25-100 mg/kg) in Swiss mice (20-25 g; N = 7/group) inhibited paw edema induced by compound 48/80 (50 percent inhibition, 100 mg/kg; P <= 0.05) and, to a lesser extent, the allergic paw edema (23 percent inhibition, 100 mg/kg; P <= 0.05). SC treatment also inhibited the edema induced by histamine (58 percent inhibition; P <= 0.05) and 5-HT (52 percent inhibition; P <= 0.05) but had no effect on platelet-aggregating factor-induced paw edema. SC prevented mast cell degranulation and the consequent histamine release in Wistar rat (180-200 g; N = 7/group) peritoneal mast cells (50 percent inhibition, 1 æg/mL; P <= 0.05) induced by compound 48/80. Pre-treatment of BALB/c mice (18-20 g; N = 7/group) with 100 mg/kg of the extract significantly inhibited eosinophil accumulation in allergic pleurisy (from 7.662 ± 1.524 to 1.89 ± 0.336 x 10(6)/cavity; P <= 0.001). This effect was related to the inhibition of IL-5 (from 70.9 ± 25.2 to 12.05 ± 7.165 pg/mL) and CCL11/eotaxin levels (from 60.4 ± 8.54 to 32.8 ± 8.4 ng/mL) in pleural lavage fluid, using ELISA. These findings demonstrate an anti-allergic effect of SC, and indicate that its anti-edematogenic effect is due to the inhibition of mast cell degranulation and of histamine and serotonin effects, whereas the inhibition of eosinophil accumulation in the allergic pleurisy model is probably due to an impairment of CCL11/eotaxin and IL-5 production.

2-(2,3-dimethylchromon-6-yl) propanoic acid (OVS-103): a potent anti-inflammatory agent.

The compound OVS-103 showed dose-dependent anti-inflammatory and anti-arthritic effects in different acute and chronic test models in rats and mice. It produced inhibition of the exudate volume and the migration of leucocytes in the carrageenan induced pleurisy test in rats. OVS-103 showed poor inhibitory effect on granuloma formation induced by cotton pellet and had no anti-pyretic and analgesic property. ALD50 in both rats and mice was more than 2000 mg/kg, p.o. and 1500 mg/kg, i.p.

Anti-anaphylactic and anti-inflammatory effects of ternatin, a flavonoid isolated from Egletes viscosa Less

Ternatin, a tetramethoxy flavone isolated from Egletes viscosa Less (Compositae), was tested for its efficacy in modulating mouse passive cutaneous anaphylaxis (PCA) and rat carrageenan-induced pleurisy. Ternatin (12.5, 25 and 50 mg/kg, ip) caused a dose-dependent inhibition of IgG antibody-mediated 1.5-h homologous PCA as well as IgE antibody-mediated 48-h homologous PCA in 2-month old mice (N = 5 per group). The inhibitory activity of ternatin was more potent on IgE-mediated PCA (47-79%) than on IgG (45-59%). In the rat carrageenan pleurisy test, ternatin (25 and 50 mg/kg, ip) reduced the response to carrageenan at 5 h both by decreasing exudate volume (33-40%) and leukocyte number (60%) in 5-6-month old rats (N = 6 per group). In contrast, indomethacin (2 mg/kg, po), a known cyclooxygenase inhibitor, showed greater potency in the inhibition of exudate volume (57%) and leukocyte number (77%). These results show that ternatin has both anti-inflammatory and anti-anaphylactic properties and suggest that it may be a useful alternative to anti-allergic drugs of the disodium cromoglycate (DSCG) type for use in bronchial asthma

PAF-acether and the acute inflammatory reaction

PAF-aceter é um fosfolipídio que exerce um papel importante na reaçäo inflamatória aguda. No modelo experimental do edema da para de rato e pleurisia, a reaçäo induzida pelo PAF era acompanhada de hemoconcentraçäo, embora esses processos pareçam ser mediados por mecanismos distintos. Antagonistas específicos do PAF, como BN 52021 e WEB 2086, inibem 60% do edema induzido pelo PAF. Leucotrienos e mecanismos histaminérgicos envolvendo receptores H2 parecem participar no processo. A participaçäo do sistema adrenérgico e de metabólitos da ciclooxigenase é controversa. Infiltraçäo de leucócitos, observada após a injeçäo de PAF, e plaquetas näo säo necessárias para a formaçäo de edema. Auto-dessensibilizaçäo induzida pelo PAF pôde ser observada, sendo seletiva e dependente a interaçäo do PAF com receptores específicos em um processo de regulaçäo depressiva ("dow-regulation"). Nenhuma participaçäo deo PAF foi observada na reaçäo inflamatória induzida pela carregenina, contrariamente áquela provocada pelo zimosan, que é principalmente dependente do PAF-aceter