ABSTRACT
Among the current treatment strategies for the peptic ulcer patient with Helicobacter pylori infection, the method of choice is triple therapy based on the concurrent use of proton inhibitors and two antibiotics. Alchornea triplinervia is a medicinal plant commonly used by people living in the Cerrado region of Brazil to treat gastrointestinal ulcers. In the present work we proposed therapy based on this medicinal plant that presents effective gastroprotective action with antibiotic effects. Oral pretreatment with methanolic extract (ME) of A. triplinervia in rats and mice decreased the gastric injuries induced by ethanol and HCl/ethanol. Increasing the dose reduced the gastroprotective effects of ME on the gastric lesions induced by nonsteroidal anti-inflammatory drug. After pylorus ligature of mice, oral administration of ME induced a decrease not only in total acid but also in the ulcer index. We also observed that ME displayed antibacterial activity against H. pylori. Liquid-liquid separation of ME indicated that active constituents responsible for the gastroprotective action are concentrated in the ethyl acetate fraction (EAF) (50% protection) rather than in the aqueous fraction, which did not induce significant gastroprotection at the same dose (100 mg/kg). EAF induced an increase of gastric mucosa prostaglandin (PG) E(2) levels, which remained high even after previous administration of indomethacin. The phytochemical profile of ME revealed that EAF contains mainly flavonoids. In conclusion, all these results suggest that ME did not show acute toxicity, but exhibited an antisecretory property, anti-H. pylori effect, and gastroprotective action. The observed effect did not involve the participation of nitric oxide or endogenous sulfhydryl groups. However, EAF showed a more efficient gastroprotective effect than ME at a lower dose and protected the gastric mucosa by increasing PGE(2).
Subject(s)
Anti-Bacterial Agents/pharmacology , Anti-Ulcer Agents/pharmacology , Euphorbiaceae , Helicobacter pylori/drug effects , Phytotherapy , Plant Extracts/pharmacology , Stomach Ulcer/prevention & control , Administration, Oral , Animals , Anti-Bacterial Agents/administration & dosage , Anti-Ulcer Agents/administration & dosage , Brazil , Dose-Response Relationship, Drug , Female , Flavonoids/analysis , Gastric Juice/drug effects , Gastric Mucosa/pathology , Helicobacter Infections/drug therapy , Humans , Male , Mice , Plant Extracts/toxicity , Prostaglandins/biosynthesis , Rats , Rats, Wistar , Stomach Ulcer/chemically inducedABSTRACT
Plantas têm contribuído no tratamento da maioria das doenças. Considerando a importância terapêutica das plantas medicinais, foi avaliada a atividade imunológica dos extratos metanólico e etanólico de Davilla elliptica. Macrófagos estão envolvidos em todos estágios da resposta imune, podendo liberar componentes como: peróxido de hidrogênio (H2O2), óxido nítrico (NO) e fator de necrose tumoral-alfa (TNF-alfa). A estimulação dos macrófagos foi avaliada pela determinação de H2O2, NO e TNF-alfa em culturas de macrófagos peritoneais de camundongos na presença dos extratos da D. elliptica. IC50 foi determinado através de ensaio utilizando MTT. Os estudos fitoquímicos realizados mostraram a presença de flavonóides derivados da quercetina e miricetina entre outros compostos. A produção de H2O2 não foi muito expressiva em ambos extratos, contudo a de NO foi significativa. Os dois extratos induziram a produção de TNF-alfa, sendo que a liberação dessa citocina pelo extrato metanólico foi quase cinco vezes maior do que pelo extrato etanólico. Uma relação entre as sínteses de NO e TNF-alfa foi observada. O aumento na produção de NO está relacionado com a indução de citocinas pró-inflamatórias como TNF-alfa. Analisando os resultados, sugere-se que os extratos metanólico e etanólico de D. elliptica podem modular a ativação de macrófagos.
Plants have contributed in a significant way to the treatment of most of the diseases. Considering the therapeutic importance of the medicinal plants, the immunological activity of the methanolic and ethanolic extract of Davilla elliptica was evaluated. In every stage of the immune response macrophages are involved and they can release many compounds such as hydrogen peroxide (H2O2), nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha). Macrophages stimulation was evaluated by the determination of H2O2, NO and TNF-alpha in peritoneal macrophages cultures of mice in the presence of the D. elliptica extracts. IC50 was determined by MTT assay. The phytochemical study showed flavonoids derived from quercetin and myricetin and other compounds. The production of H2O2 was not very expressive in both extracts, but they presented a significant effect on NO production. The two extracts induced TNF-alpha production, although the methanolic liberated almost five times more TNF-alpha than the ethanolic one. A relationship among the synthesis of NO and TNF-alpha was observed. The increase of NO production is related with the induction of proinflammatory cytokines like TNF-alpha. Analyzing the results, it is suggested that methanolic and ethanolic extract of D. elliptica can modulate macrophage activation.
