Gastroprotective Effects (in Rodents) Of A Flavonoid Rich Fraction Obtained From Syngonanthus Macrolepsis.

Syngonanthus macrolepis, popularly known in Brazil as 'sempre-vivas', is a plant from the family Eriocaulaceae, it is found in the states of Minas Gerais and Bahia. The species contains a variety of constituents, including flavonoids with gastroprotective effect. In this work, a flavonoid-rich fraction (Sm-FRF) obtained from scapes of S. macrolepis was investigated for preventing gastric ulceration in mice and rats. The activity was evaluated in models of induced gastric ulcer (absolute ethanol, stress, non-steroidal anti-inflammatory drugs and pylorus ligation). The cytoprotective mechanisms of the Sm-FRF in relation to sulfhydryl (SH) groups, nitric oxide (NO) and antioxidant enzymes were also evaluated. The Sm-FRF (100 mg/kg, p.o.) significantly reduced gastric injury in all models, and did not alter gastric juice parameters after pylorus ligation. The results indicate significant gastroprotective activity for the Sm-FRF, which probably involves the participation of both SH groups and the antioxidant system. Both are integral parts of the gastrointestinal mucosa's cytoprotective mechanisms against aggressive factors.

Involvement of nitric oxide in the gastroprotective effects of an aqueous extract of Pfaffia glomerata (Spreng) Pedersen, Amaranthaceae, in rats

The plants belonging to Pfaffia genus are used in folk medicine to treat gastric disturbances. This study examined the effects of an aqueous extract of Pfaffia glomerata (Spreng) Pedersen (AEP) on the gastrointestinal tract. Wistar rats were pretreated orally (p.o.) with the AEP (125, 250, 500 and 1000 mg.kg(-1)) before induction of ulcers by hypothermic restraint stress (HRS, 3 h restraint stress at 4 degreesC), ethanol (ET, 70%; 0.5 ml/animal; p.o.) or indomethacin (IND, 20 mg.kg(-1); s.c.). Control animals received water (C) or ranitidine (60 mg.kg(-1)) p.o. The AEP protected rats against HRS and ET-induced ulcers, but was not able to protect the gastric mucosa against IND-induced ulcers. When injected into the duodenal lumen, the AEP reduced total acidity and both basal and histamine-stimulated acid secretion in pylorus-ligated rats. In addition, gastric secretion from AEP-treated animals exhibited increased concentrations of nitrite and nitrate. Treatment of animals with L-NAME (120 mg.kg(-1), p.o.) prevented both the reduction of total acidity and the increase in NO, levels promoted by AEP treatment. In conclusion, AEP effectively protected the gastric mucosa and inhibited gastric acid secretion in rats, probably by involving the histaminergic pathway and an enhanced production of nitric oxide in the stomach. (C) 2003 Elsevier B.V. All rights reserved.

Gastroprotective effects (in rodents) of a flavonoid rich fraction obtained from Syngonanthus macrolepsis

Objectives: Syngonanthus macrolepis, popularly known in Brazil as sempre-vivas', is a plant from the family Eriocaulaceae, it is found in the states of Minas Gerais and Bahia. The species contains a variety of constituents, including flavonoids with gastroprotective effect. In this work, a flavonoid-rich fraction (Sm-FRF) obtained from scapes of S.macrolepis was investigated for preventing gastric ulceration in mice and rats.MethodsThe activity was evaluated in models of induced gastric ulcer (absolute ethanol, stress, non-steroidal anti-inflammatory drugs and pylorus ligation). The cytoprotective mechanisms of the Sm-FRF in relation to sulfhydryl (SH) groups, nitric oxide (NO) and antioxidant enzymes were also evaluated.Key findingsThe Sm-FRF (100mg/kg, p.o.) significantly reduced gastric injury in all models, and did not alter gastric juice parameters after pylorus ligation.ConclusionsThe results indicate significant gastroprotective activity for the Sm-FRF, which probably involves the participation of both SH groups and the antioxidant system. Both are integral parts of the gastrointestinal mucosa's cytoprotective mechanisms against aggressive factors.

Antinociceptive, anti-inflammatory and gastroprotective effects of a hydroalcoholic extract from the leaves of Eugenia punicifolia (Kunth) DC. in rodents

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Antinociceptive, anti-inflammatory and gastroprotective effects of a hydroalcoholic extract from the leaves of Eugenia punicifolia (Kunth) DC. in rodents

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Does the gastroprotective action of a medicinal plant ensure healing effects? An integrative study of the biological effects of Serjania marginata Casar. (Sapindaceae) in rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Gastroprotective effect of Cissus sicyoides (Vitaceae): Involvement of microcirculation, endogenous sulfhydryls and nitric oxide

Aim of the study: Cissus sicyoides L. is a medicinal plant popularly known in Brazil against various diseases and the research interest in this plant is justifiable because of its potential medicinal value in stomachache and gastric ulcer.Materials and methods: The methanolic extract obtained from the leaves of Cissus sicyoides (Cc) was evaluated for the ability to protect the gastric mucosa against injuries caused by necrotizing agents (0.3 M HCl/60% EtOH, absolute ethanol, piroxicam and pylorus ligature) in rodents. We also evaluated microcirculation, antioxidant action and participation of NO (nitric oxide) and sulfhydryls (SH) groups in the Cc gastroprotective action.Results: Administration of Cc significantly reduced gastric lesions induced by different ulcerogenic agents in rodents. This extract administered by oral route significantly increased gastric volume without exerting antisecretory effect. The Cc effect involved an increase of the defense mechanism of the gastrointestinal mucosa such as NO and SH groups that prevent and attenuate the ulcer process. The Cc also has antioxidant property against oxidative stress but does not modify microcirculation response in gastric mucosa.Conclusions: These results confirmed the traditional use of Cissus sicyoides for the treatment of gastric ulcer. (C) 2008 Elsevier B.V. All rights reserved.

Morphologic and Pharmacological Investigations in the Epicatechin Gastroprotective Effect

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Abarema cochliacarpos: Gastroprotective and ulcer-healing activities

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Gastroprotective effect of the ethanolic extract and fractions obtained from syngonanthus bisulcatus Rul

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Hydrogen Sulfide Prevents Ethanol-Induced Gastric Damage in Mice: Role of ATP-Sensitive Potassium Channels and Capsaicin-Sensitive Primary Afferent Neurons

The aim of this study was to evaluate the protective effect of hydrogen sulfide (H(2)S) on ethanol-induced gastric lesions in mice and the influence of ATP-sensitive potassium (K(ATP)) channels, capsaicin-sensitive sensory afferent neurons, and transient receptor potential vanilloid (TRPV) 1 receptors on such an effect. Saline and L-cysteine alone or with propargylglycine, sodium hydrogen sulfide (NaHS), or Lawesson`s reagent were administrated for testing purposes. For other experiments, mice were pretreated with glibenclamide, neurotoxic doses of capsaicin, or capsazepine. Afterward, mice received L-cysteine, NaHS, or Lawesson`s reagent. After 30 min, 50% ethanol was administrated by gavage. After 1 h, mice were sacrificed, and gastric damage was evaluated by macroscopic and microscopic analyses. L-Cysteine, NaHS, and Lawesson`s reagent treatment prevented ethanol-induced macroscopic and microscopic gastric damage in a dose-dependent manner. Administration of propargylglycine, an inhibitor of endogenous H(2)S synthesis, reversed gastric protection induced by L-cysteine. Glibenclamide reversed L-cysteine, NaHS, or Lawesson`s reagent gastroprotective effects against ethanol-induced macroscopic damage in a dose-dependent manner. Chemical ablation of sensory afferent neurons by capsaicin reversed gastroprotective effects of L-cysteine or H(2)S donors (NaHS or Lawesson`s reagent) in ethanol-induced macroscopic gastric damage. Likewise, in the presence of the TRPV1 antagonist capsazepine, the gastroprotective effects of L-cysteine, NaHS, or Lawesson`s reagent were also abolished. Our results suggest that H(2)S prevents ethanol-induced gastric damage. Although there are many mechanisms through which this effect can occur, our data support the hypothesis that the activation of K(ATP) channels and afferent neurons/TRPV1 receptors is of primary importance.

Constituents and antiulcer effect of Alchornea glandulosa: Activation of cell proliferation in gastric mucosa during the healing process

Alchornea glandulosa (Euphorbiaceae) is a plant used in folk medicine as an antiulcer agent. Rats pretreated with methanolic extract obtained from the leaves of A. glandulosa (AG) showed a dose-dependent effect and significant reduction of gastric ulcers induced by absolute ethanol at the doses of 500 (57%) and 1000 mg/kg (35%) in relation to the control group. Pretreatment of mice with AG (500, 1000 mg/kg, p.o.) showed dose-dependent activity and significantly decreased the severity of lesions caused by HCl/ethanol and by non steroidal anti inflammatory drug-induced gastric lesions. Pretreatment with AG also induced antisecretory action via local and systemic routes and a significant decrease in the total gastric acid content. The gastroprotective effects of AG involved the participation of nitric oxide and increased levels of endogenous sulfhydryl compounds, which are defensive mechanisms of the gastrointestinal mucosa against aggressive factors. The ability of AG to heal gastric ulcers was evaluated after 14 consecutive days of treatment. The results showed that single oral administrations of AG (250 mg/kg/once daily) potently stimulates gastric epithelial cell proliferation that contributes to the accelerated healing of gastric ulcers induced by acetic acid. In addition, no subacute toxicity (body weight gain, vital organs, and serum biochemical parameters) was observed during treatment with AG. Phytochemical investigation of AG led to the isolation of myricetin-3-O-alpha-L-rhamnopyranoside, quercetin-3-O-alpha-L-arabinopyranoside, quercetin-3-O-beta-D-galactopyranoside, quercetin, amentoflavone, methyl gallate, gallic acid, and pterogynidine. We also established the phytochemical profile of AG with the quantification of total phenolic compounds. These compounds may contribute to the observed antiulcerogenic effects of AG.

Brazilian Medicinal Plant Acts on Prostaglandin Level and Helicobacter pylori

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Indigofera suffruticosa Mill as new source of healing agent: Involvement of prostaglandin and mucus and heat shock proteins

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Can the aqueous decoction of mango flowers be used as an antiulcer agent?

This study was designed to determine the effect of Mangifera indica flowers decoction, on the acute and subacute models of induced ulcer in mice and rats. A single oral administration of the aqueous decoction (AD) from M. indica up to a dose of 5 g/kg, p.o. did not produce any signs or symptom of toxicity in the treated animals. The oral pre-treatment with AD (250, 500 and 1000 mg/kg) in rats with gastric lesions induced by ethanol, decreased the gastric lesions from 89.0 +/- 6.71 (control group) to 9.25 +/- 2.75, 4.50 +/- 3.30 and 0, respectively. Pretreatment with AD (250, 500 and 1000 mg/kg) to mice with HCl/ethanol- or stress-induced gastric lesions resulted in a dose-dependent significant decrease of lesion index. In the piroxicam-induced gastric lesions, the gastroprotective effect of AD was reducing with the increase of the AD dose. In the pylorus-ligature, AD (p.o.) significantly decreased the acid output indicating the antisecretory property involved in the gastroprotective effect of M. indica. Treatment with AD during 14 consecutive days significantly accelerated the healing process in subacute gastric ulcer induced by acetic acid in rats. Pretreatment with N-nitro-L-arginine methyl ester (L-NAME), an inhibitor of NO-synthase, did not abolish the gastroprotective effects (99% with saline versus 80% With L-NAME) of AD against ethanol-induced gastric lesions. Pretreatment with N-ethylmaleimide (NEM), a blocker of endogenous sulphydryl group, significantly abolished the protective effects of AD against ethanol-induced gastric ulcers (95% with saline versus 47% with NEM). Phytochemical screening showed the presence of steroids, triterpenes, phenolic compounds and flavonoids. Estimation of the global polyphenol content in the AD was performed by Folin-Ciocalteu method and showed approximately 53% of total phenolic on this extract. These findings indicate the potential gastroprotective and ulcer-healing properties of aqueous decoction of M. indica flowers and further support its popular use in gastrointestinal disorders in Caribbean. (c) 2005 Elsevier B.V.. All rights reserved.