77 research outputs found
Effects of tea from Turnera ulmifolia L. on mouse gastric mucosa support the Turneraceae as a new source of antiulcerogenic drugs
Turnera ulmifolia is a plant belonging to the family Turneraceae, popularly known in Brazil as chanana. This species is distributed from Guyana to southern Brazil where it is considered a weed. The plant occurs in tropical rain forest, fields, and gardens. Chanana tea is used in Brazilian folk medicine for the treatment of diseases related mainly to gastric dysfunction including gastric and duodenal ulcers. In this study, the ability of a lyophilized infusion, as an aqueous fraction (AqF) of the aerial parts of T. ulmifolia, was investigated for its ability to prevent ulceration of the gastric and duodenal mucosa was examined in mice and rats, respectively. The AqF significantly reduced the formation of lesions associated with HCl/ethanol administration by 39% and 46%, respectively, at doses of 500 mg/kg and 1000 mg/kg, p.o. The AqF also significantly reduced the incidence of gastric lesions induced by a combination of indomethacin and bethanechol by 58% and 72% at doses of 500 mg/kg and 1000 mg/kg, respectively. In stress-induced gastric ulcer, the inhibition by the AqF was 48%, 57%, and 58% at doses of 250 mg/kg, 500 mg/kg, and 1000 mg/kg, respectively (p<0.05). A pyloric ligature experiment showed that the highest dose of the AqF significantly affected the gastric juice parameters by increasing the pH from 2.5 (control) to 5.3 and decreasing the acid output from 11.3 (control) to 3.7 mEq/ml/4 h. The AqF had no significant effect on duodenal ulcers induced by cysteamine. Preliminary phytochemical screening confirmed that flavonoids were the major constituents of the AqF of T. ulmifolia. These results indicate that this extract has a significant antiulcerogenic effect, as popularly believed.25448749
Antiulcerogenic activity of four extracts obtained from the bark wood of Quassia amara L. (Simaroubaceae)
Quassia amara L., a neotropical forest shrub of the Simaroubaceae family, is widely used in Caribbean folk medicine and in some northern states of Brazil for the treatment of gastric ulcers. This plant is a source of numerous compounds including both beta-carbonile and cantin-6 alkaloids as well as, primarily, the bitter compounds known as quassinoids. We analyzed the possible antiulcerogenic activities of four extracts of different polarities: 70% ethanol (70% EtOH), 100% EtOH, 100% dichloromethane (DCM), and 100% hexane (HEX) obtained from Quassia amara bark. All extracts, administered at doses of 5000 mg/kg orally and 1000 mg/kg intraperitoneally, caused neither toxicity or death. In the indomethacin[bethanechol-induced gastric ulcer, 70% EtOH, 100% EtOH, DCM and HEX extracts, 100 mg/kg, p.o., inhibited the gastric ulcer (22.5, 23.4, 50.5, 46.8%, respectively). 70% EtOH, 100% EtOH, DCM, and HEX extracts reduced the gastric injury induced by the hypothermic restraint-stress test in mice (70.7, 80, 60, 82.7%, respectively). In the pylorus ligature of the mouse stomach, following pre-treatment with a single intraduodenal administration of 100 mg/kg of each extract, only 70% EtOH did not change the biochemical parameters of gastric juice. 100% EtOH, DCM and HEX extracts presented decreased gastric juice content, increased pH values and decreased acid output. We also determined the antiulcerogenic activity on HCl-EtOH-induced gastric ulcers in mice at four doses (25, 50, 75, 100 mg/kg, p.o.), then evaluated the possible dose-dependent relation and calculated the ED50 values. Except for 70% EtOH at a dose of 25 mg/kg, the other extracts showed significantly activity (p<0.05). The free mucous amount in the gastric stomach content was also evaluated. All extracts showed significant increases (p<0.05) of free mucous. This effect was abolished when the animals were pre-treated with indomethacin. Prostaglandin synthesis was evaluated by the administration of HEX extracts by the oral route (100 mg/kg). Prostaglandin synthesis was significantly, increased by 52.3% (p<0.05), and this effect was abolished with prior administration of indomethacin. We concluded that Quassia amara is a probable source for a new drug to treat gastric ulcers, and the mechanism of its activity relates to cytoprotective factors, such as mucous and prostaglandins, but there is still the possibility that antisecretory activity is involved in its antiulcerogenic effect.2591151115
Chronic administration of Abarema cochliacarpos attenuates colonic inflammation in rats
Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES)Inflammatory bowel diseases are characterized by a chronic clinical course of relapse and remission associated with self-destructive inflammation of the gastrointestinal tract. Active extracts from plants have emerged as natural potential candidates for its treatment. Abarema cochliacarpos (Gomes) Barneby & Grimes, Fabaceae (Barbatimao), is a native medicinal plant in to Brazil. Previously we have demonstrated in an acute colitis model a marked protective effect of a butanolic extract, so we decided to assess its anti-inflammatory effect in a chronic ulcerative colitis model induced by trinitrobenzensulfonic acid (TNBS). Abarema cochliacarpos (150 mg/day, v.o.) was administered for fourteen consecutive days. This treatment decreased significantly macroscopic damage as compared with TNBS. Histological analysis showed that the extract improved the microscopic structure. Myeloperoxidase activity (MPO) was significantly decreased. Study of cytokines showed that TNF-alpha was diminished and IL-10 level was increased after Abarema cochliacarpos treatment. In order to elucidate inflammatory mechanisms, expression of cyclooxygenase (COX)-2 and nitric oxide synthase (iNOS) were studied showing a significant downregulation. In addition, there was reduction in the JNK and p-38 activation. Finally, I kappa B degradation was blocked by Abarema cochliacarpos treatment being consistent with an up-regulation of the NF-kappaB-binding activity. These results reinforce the anti-inflammatory effects described previously suggesting that Abarema cochliacarpos could provide a source for the search for new anti-inflammatory compounds useful in ulcerative colitis treatment.214680690Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES)Universidade Estadual de Alagoas, BrazilInstituto Federal de Educacao Ciencia e Tecnologia-Sergipe, BrazilCoordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES
Antigenotoxic effects of Mandevilla velutina (Gentianales, Apocynaceae) crude extract on cyclophosphamide-induced micronuclei in Swiss mice and urethane-induced somatic mutation and recombination in Drosophila melanogaster
40 YEARS OF BRAZILIAN MEDICINAL PLANT RESEARCH
The Brazilian Foundation of Medicinal Plants has developed a medicinal plant database. Data were obtained from communications presented in Brazilian Scientific Meetings in the 1949-1989 period and include plant species, family, local name, part used, extract analyzed, claimed therapeutic action, pharmacological activity and active compounds. The families most frequently studied and the usual popular indications are analyzed. The history of research during this period and the current state of medicinal plant research in Brazil are outlined.391536
How to study the pharmacology of medicinal plants in underdeveloped countries
This paper presents a reflection based on 15 years' experience of studies on the pharmacology of medicinal plants in an underdeveloped country, Brazil. In these countries the investment in research is small and frequently interrupted. There is no new-medicines development program. Brazilian pharmaceutical companies have been short-sighted and have not developed new drugs. Although the diversity of the Brazilian flora is a remarkable opportunity for the development of new medicine products, natural product research is limited to a small group. These difficulties are common to all underdeveloped countries. Strategies for the pharmacological study of medicinal plants are proposed, the main difficulties are identified and a discussion of possible ways to overcome them is presented.544170013113
Oral anti-inflammatory and anti-ulcerogenic activities of a hydroalcoholic extract and partitioned fractions of Turnera ulmifolia (Turneraceae)
Anti-inflammatory studies were conducted on rats or mice using a crude hydroalcoholic extract of the aerial parts of Turnera ulmifolia and it's partitioned fractions. i,e. the aqueous, ethyl acetate and ethanolic fractions. The hydroalcoholic extract and it's fractions (aqueous and ethanolic) inhibited carragreenan-induced edema. However, only the ethanolic fraction was used in the other experiments due to it's yield. The extract also inhibited the cotton pellet granuloma and the increase of vascular permeability induced by histamine, 5-hydroxytryptamine and prostaglandin E-2, but not that produced by bradykinin. The extract or the fraction did not present analgesic activity in the writhing test using acetic acid and did not reduce croton oil-induced ear edema in mice. When the ethanolic fraction and LPS were administered i.p. to Balb/C mice 72 h before blood or peritoneal fluid collection. no changes were observed in the white or total blood cell counts in the peripheral blood. On the other hand, changes were observed in both total and differential cell counts in the peritoneal exudate since all doses of the fraction reduced the number of total leukocytes (mainly lymphocytes) obtained from the peritoneal exudate. In contrast to nonsteroidal anti-inflammatory drugs, the administration of the hydroalcoholic extract or the ethanolic fraction alone did not potentiate gastric mucosal lesions induced by aspirin. The extract and the fraction inhibited the appearance of gastric lesions induced by indomethacin, ethanol and pylorus ligature, but not those induced by stress. As also observed with carbenoxolone, the ethanolic fraction increased the wall mucus in hypothermical-restraint stress-induced gastric lesions. The anti-ulcerogenic effect of the extract and of the ethanolic fraction may be related to an increase of mucosal defensive factors, such as prostaglandin and mucus. The anti-inflammatory actions of the extract and the fraction may be due to an inhibitory effect on histamine and cyclooxygenase II, but not on cyclooxynenase I, because the extract and it's fraction present both anti-inflammatory and anti-ulcerogenic effects. The major substances present in the ethanolic fraction are flavonoids which will be isolated and identified. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.61321522
Effects of prolonged administration of Musa paradisiaca L (banana), an antiulcerogenic substance, in rats
In Brazil, unripe banana as well as the latex obtained from the top of the inflorescence are popularly used in the treatment of gastroduodenal ulcers, especially in the poorest regions. However, adverse effects In fasted subjects treated with unripe banana have been described. Thus, the antiulcerogenic effects of Brazilian banana samples and possible toxic effects of prolonged administration of unripe banana in rats were studied. The analysed samples of Musa paradisiaca showed antiulcer effects in all models employed. Moreover, following 5 weeks of oral treatment with unripe powdered banana, small alterations in some haematologic and biochemical parameters were observed. No significant differences were observed on evaluated physiological parameters. These results provide evidence that treatment with unripe banana is acceptable and could be recommended by official health authorities. (C) 1997 by John Wiley & Sons, Ltd.111283
Petiveria alliacea L extract protects mice against Listeria monocytogenes infection - Effects on bone marrow progenitor cells
In this study we have investigated the effects of Petiveria alliacea on the hematopoietic response of mice infected with Listeria monocytogenes. Our results demonstrate a protective effect of the crude extract of P. alliacea since the survival of the treated/infected was higher than that in the infected group. Moreover, the number of granulocyte/macrophage colonies (CFU-GM) and the serum colony stimulating activity levels were increased in the treated/infected mice in relation to the infected group. These results suggest an immunomodulation of Petiveria alliacea extract on hematopoiesis, which may be responsible, at least in part, for the increased resistance of mice to Listeria monocytogenes infection.21110912
Gastric antiulcerogenic effects of Dalbergia monetaria L in rats
The antiulcerogenic activity of Dalbergia monetaria L. (Leguminosae-Fabaceae) lyophilized aqueous extract (LAE) was studied in four models of gastric ulcers in rats, LAE showed a dose dependent inhibition of gastric lesions induced by indomethacin, ethanol, pylorous ligature and hypothermic-restraint stress. LAE extract was more effective against hypothermic-restraint stress-induced lesions and less effective against indomethacin-induced gastric mucosal damage, The effectiveness on the ethanol and pylorus ligature induced gastric lesions was equivalent, On the other hand, LAE did not modify mucus secretion in gastric lesions induced by stress, The oral administration of LAE did not produce any toxicity signals until 5 g/kg, Proanthocyanidins present in this species are phenolic compounds that inhibit the histidine decarboxylase enzyme, Thus, the mechanism involved in the reduction of ulcerative lesions of rat gastric mucosa produced by the LAE of D. monetaria may be related to its property of inhibiting histamine production. (C) 1997 by John Wiley & Sons, Ltd.11431431
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