J.A.A. Sertié

Pharmacological assay of Casearia sylvestris. I: Preventive anti-ulcer activity and toxicity of the leaf crude extract

An ethanol extract of the leaves of Brazilian Casearia sylvestris, given orally, inhibited gastric secretion in pylorus-ligated rats. At a prophylactic dose of 57.5 mg/kg, the extract showed a reduction of gastric juice more effective than misoprostol (500 micrograms/kg). In reducing hydrochloric acid output, the extract was less effective than misoprostol, cimetidine (32.0 mg/kg) and atropine (5.3 mg/kg). With the extract, the pH of the stomach contents was not significantly different from that of controls. Stress-induced lesions produced by restraint and water immersion were significantly prevented by the extract for all levels of severity when compared with the controls. The extract appeared more effective than misoprostol in suppressing light lesions, was equivalent to cimetidine and misoprostol for moderate lesions, and less effective than cimetidine and misoprostol for severe lesions. Toxicological experiments indicated a low acute toxicity, confirmed by subchronic daily testing. The oral LD50 value of greater than 1840 mg/kg was over 32 times higher than the antiulcerogenic ED50 (57.5 mg/kg).

Anti-inflammatory effect of the hydralcoholic extract of Zingiber officinale rhizomes on rat paw and skin edema

Plant extracts have been used for centuries as a popular mode of treatment for several health disorders. Over the last ten years, the study of those extracts has attracted attention in different fields of the biological sciences. Ginger, the rhizome of Zingiber officinale Roscoe (Zingiberaceae), is a commom constituent of diet worldwide and it has been reported that its extracts present some pharmacological activities. Here we investigate the effects of the crude hydralcoholic extract of ginger rhizomes on the classical models of rat paw and skin edema. The carrageenan-, compound 48/80- or serotonin-induced rat paw edema were inhibited significantly by the intraperitoneal administration of alcoholic ginger extract. Ginger extract was also effective in inhibiting 48/80-induced rat skin edema at doses of 0.6 and 1.8 mg/site. Rat skin edema induced by substance P or bradikinin was not affected by treatment with Z. officinalle extract. The intraperitoneal administration of ginger extract (186 mg/kg(-1) body wt.) 1 h prior to serotonin injections, reduced significantly the serotonin-induced rat skin edema. Our results demonstrated that crude extract of Zingiber officinale was able to reduce rat paw and skin edema induced by carrageenan, 48/80 compound and serotonin. The antiedematogenic activity seems to be related, at least partially, to an antagonism of the serotonin receptor.

Antiulcer activity of the crude extract from the leaves of casearia sylvestris.

In rats, administration of Casearia sylvestris extract derived from fresh and dried leaves protects stomach mucosa without changing gastric pH. In stress-induced acute lesions, the preventive effect of extract from dried leaves is more effective than extract from fresh leaves. In acetic acid-induced chronic ulcer, both extracts reduce the size of ulceration and increase the number of collagen fibers after 5 days of treatment, and these effects are similar with both extracts. These antiulcer activities of Casearia sylvestris may be due to the presence of volatile oils, tannins and triterpenerelated compounds.

Antiulcer activity of Sapindus saponaria L. in the rat.

Extracts of leaves and fruits of Sapindus saponaria L. were orally administered to rats and the parameters of gastric secretion (volume, pH and acidity) were evaluated after pylorus ligature. The inhibitory effect of the extracts on lesions induced by stress was compared to that of cimetidine. The volume and concentration of hydrochloric acid were reduced after oral administration of the extracts. A significant reduction of the lesion index was observed in the acute assays. No significant alteration in body or organ weight was detected in animals treated orally for 30 days with the extracts. These results suggest that S. saponaria fruits have an anti-gastric ulcer potential.

Pharmacological assay of Cordia verbenacea III: Oral and topical antiinflammatory activity and gastrotoxicity of a crude leaf extract

The antiinflammatory effects and gastrotoxicity of a lyophilized 70% ethanol extract of the leaves of Cordia verbenacea were investigated through experimental models in rats and mice. The oral administration of 1.24 mg/kg of the extract significantly inhibited nystatin-induced oedema. Topical application of the extract at a dose of 0.09 mg/ear in mice was clearly more effective than 1.0 mg/ear of naproxen in the reduction of the ear oedema induced by corton oil. At antiinflammatory doses, the extract showed an important protective effect on the gastric mucosa, reducing significantly the number of gastric lesions.

The anti-Inflammatory and analgesic effects of a crude extract of Petiveria alliacea L. (Phytolaccaceae)

Petiveria alliacea L (Phytolaccaceae) is a perennial bush plant that grows widely in Brazil. The roots and leaves of P. alliacea have been used in folk medicine for their antispasmodic, sedative, diuretic and antihelminthic actions. We recently described the anti-inflammatory properties of P. alliacea administered topically and orally in different animal models. In the present study, we investigated the anti-inflammatory activity of a crude lyophilized extract of P. alliacea roots administered to rats with pleurisy. The oral administration of P. alliacea root extract did not significantly reduce the total number of leukocytes at the doses tested. By contrast, the highest dose of extract tested (43.9 mg/kg body wt.) significantly reduced the number of migrating neutrophils, mononuclear cells and eosinophils; the dose of 31.4 mg/kg body wt. also reduced mononuclear cell migration. The P. alliacea root extract also showed a significant analgesic effect in the experimental model used. The results of this study provide a basis for the use of P. alliacea extracts in popular folk medicine, but further studies are necessary to elucidate the mechanism of its anti-inflammatory and analgesic actions.

Antiulcer action of Microgramma squamulosa (Kaulf.) Sota

Microgramma squamulosa (Kaulf.) Sota (Polypodiaceae) is commonly used as an antiulcer agent in the state of São Paulo, mainly in the upper land. The present work aims to study the antiulcer action of the crude extract of the plant rhizome and its toxicity. The effective dose was determined through acute ulcer induction test by stress. Using a determined dose, we performed a test against ulcer through acute induction by ethanol and hydrochloric acid, using cimetidine and misoprostol as reference drugs in both tests. The same extract, its ethanol and ethanol + water (1:1) fractions and the reference drug cimetidine were tested through subchronic induction test with acetic acid. The subchronic toxicity test was performed using a dose of 800 mg/kg of the crude extract, orally administered for 30 days. Finally the extracts and fractions were analysed in order to determine the main chemical groups of substances.

Miconazole as Inflammatory Agent. II: Time Course of Pleurisy and Drug Interference

1. Miconazole-induced pleurisy was characterized by edema development and leukocyte infiltration. 2. This response was inhibited by chlorpheniramine, methysergide and steroidal and nonsteroidal anti-inflammatory drugs. 3. After miconazole injection, no mast cells were found in the pleural cavity. 4. Our results support the concept that biogenic amines released from mast cells and cyclooxygenase-derived mediators may contribute to the pathogenesis and evolution of miconazole inflammation.

Protector mechanisms of the association between gastroesophageal reflux disease and asthma: experimental study in rats

BACKGROUND It is well known the association between gastroesophageal reflux disease and asthma. The hyperreactivity of the airways is a characteristic of an asthmatic. Many studies associate the increase of the airways reactivity with gastroesophageal reflux disease. AIM In this study we have evaluated the effect of the intraluminal exposition to gastric juice of trachea on the reactivity to methacholine from rats submitted to a pulmonary allergic inflammation. METHODS Group of rats were sensitized and challenged with ovalbumin. After 24 hours the animals were sacrificed, and their tracheae were removed to be cultured with gastric juice. The gastric juice was obtained from a donor rat. Subsequently the segments were placed into plastic plates with RPMI-1640 for incubation, under suitable atmosphere and time. After the period of incubation the segments were put into chambers for the analysis of the contractile response to methacholine. RESULTS We observed reduction in the contractile response of trachea cultured with gastric juice from allergic rats. This result was confirmed by the pharmacological treatments with compound 48/80 and dissodium cromoglicate (mast cells blockade), L-NAME (nitric oxide inhibitor, NO), capsaicin (neuropeptides depletion) and indomethacin (ciclooxigenase inhibitor). CONCLUSIONS Our results highlight to the existence of a complex interaction between pulmonary allergy and gastric juice in the airways. The involvement of the non-adrenergic non-cholinergic system, NO, prostanoids and mast cells are directly related to this interaction. We suggest that the reduced contractile response observed in vitro may represent a protector mechanism of the airways. Despite its presence in the human body it can not be observed due to the predominant effects of excitatory the non-adrenergic non-cholinergic system.

Miconazole as inflammatory agent—I. Cellular and pathophysiological effects

1. Subcutaneous injection of miconazole into the rat paw evoked an acute, circumscribed and long-lasting inflammation. 2. Miconazole edema presented two defined phases of rapid swelling. 3. Miconazole edema was antagonized by chlorpheniramine, dexamethasone and phenylbutazone. 4. This edema was 1.5-2 times more intense than edema due to econazole. 5. It is suggested that miconazole paw edema might be useful in the process of screening anti-inflammatory drugs.