Healing Actions of Essential Oils from Citrus aurantium and d-Limonene in the Gastric Mucosa: The Roles of VEGF, PCNA, and COX-2 in Cell Proliferation

Previous studies have described the gastroprotective effects of essential oils that are derived from Citrus aurantium (OEC) and its main compound d-limonene (LIM) in a model of chemically induced ulcers in rats. However, these studies do not address the compound's healing effects on the gastric mucosa. Thus, the aim of this work was to evaluate the healing activity of OEC and LIM in acetic acid-induced gastric ulcers in rats, a model that reproduces human chronic ulcers. The obtained results demonstrated that lower effective doses of OEC (250mg/kg) and LIM (245mg/kg) induced gastric mucosal healing with a cure rate of 44% and 56%, respectively, compared with the control group (P<.05). During the 14 days of OEC or LIM treatment, none of the groups demonstrated toxicity in terms of body and organ weight or serum biochemical parameters. Both OEC and LIM treatment promoted an increase in epithelial healing, as confirmed by immunohistochemistry, which was greater in the animals that were treated with the positive control. In addition, both treatments increased cellular proliferation as measured by proliferating cell nuclear antigen and cyclooxygenase 2 expression in the gastric mucosa, vascular endothelial growth factor-mediated blood vessel formation in the margin of the ulcer, and production of gastric mucus, which fortifies the gastric protective barrier. We concluded that OEC and LIM, two common flavoring agents, promote gastric mucosal healing without any apparent toxic effect, resulting in better gastric epithelial organization in the treated rats.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Involvement of Glutathione, Sulfhydryl Compounds, Nitric Oxide, Vasoactive Intestinal Peptide, and Heat-Shock Protein-70 in the Gastroprotective Mechanism of Croton cajucara Benth. (Euphorbiaceae) Essential Oil

This study aimed to evaluate the gastroprotective mechanism of action of the essential oil of Croton cajucara Benth. (Euphorbiaceae) stem bark in ethanol-induced gastric ulcers and its in vitro anti-Helicobacter pylori activity. The involvement of heat-shock protein-70, vasoactive intestinal peptide, glutathione, nitric oxide, and nonprotein sulfhydryl compounds in the gastroprotective effect was determined in male Wistar rats. The minimum inhibitory concentration against H. pylori was determined in vitro. The results were analyzed by analysis of variance followed by the Dunnett test, and a P value less than 0.05 was considered to represent a statistically significant difference. C. cajucara decreased ethanol-induced ulcer area in 100% of ulcers and decreased the histologic lesions. In the C. cajucara group, the area marked by heat-shock protein-70 was significantly higher than the area in the control group; this finding was not seen for vasoactive intestinal peptide. C. cajucara could not maintain glutathione levels close to those in the sham group. The gastric ulcer area of rats treated with the sulfhydryl compound blocker was decreased, but the ulcer area of rats treated with nitric oxide synthase inhibitor showed no alteration. The minimum inhibitory concentration obtained for C. cajucara was 125 mu g/mL. These findings suggest that sulfhydryl compounds and heat-shock protein-70, but not nitric oxide, glutathione, or vasoactive intestinal peptide, are involved in the C. cajucara gastroprotective effect against ethanol-induced gastric ulcers.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Effects of limonene and essential oil from Citrus aurantium on gastric mucosa: Role of prostaglandins and gastric mucus secretion

Essential oil from Citrus aurantium and the monoterpene limonene are widely used flavoring agents that are found in some common food items. This specie is also used medicinally throughout the world to treat gastritis and gastric disorders. Therefore, biological assays were performed in vivo on essential oil of C aurantium (OEC) and its majority compound limonene (LIM) to evaluate their effect on gastric mucosa. The OEC (250 mg/kg, p.o.) and LIM (245 mg/kg, p.o.) provided effective (99%) gastroprotection against lesions induced by absolute ethanol and NSAID (non-steroidal anti-inflammatory drug) in rats. OEC and LIM do not interfere with gastric H(+) secretion, serum gastrin or glutathione (GSH) level in gastric mucosa. But the gastroprotective action of OEC and LIM occurs due to an increase in the gastric mucus production induced by conserving the basal PGE(2) levels after challenge by agents harmful to the gastric mucosa. Given that LIM and OEC are excellent flavoring agents and also present gastroprotective actions, they can be regarded as a promising target for the development of a new drug for the prevention of gastric damage. Published by Elsevier B.V.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Davilla elliptica and Davilla nitida: Gastroprotective, anti-inflammatory immunomodulatory and anti-Helicobacter pylori action

Ethnopharmacological relevance: Davilla elliptica and Davilla nitida are species commonly found in the Brazilian Cerrado biome.Aim of the study: Based on ethnopharmacological and phytochemical analyses, methanolic extracts from leaves of Davilla elliptica (EDE) and Davilla nitida (EDN) were evaluated for their anti-ulcer, anti-inflammatory, immunological and anti-Helicobacter pylori activities.Materials and methods: The gastroprotective action of both extracts was evaluated in rodent experimental models (HCl/ethanol, ethanol or NSAID). We also evaluated anti-inflammatory (carrageenin-induced rat hind paw edema), immunomodulatory (murine peritoneal macrophages) and antibacterial action of both extracts against a standard strain of Helicobacter pylori.Results: EDE and EDN (500 mg/kg) were able to protect gastric mucosa against HCl/ethanol solution (EDE 63%; EDN 59%), absolute ethanol (EDE 95%; EDN 88%), and also against injurious effect of NSAID (EDE 77%: EDN 67%). When EDE and EDN were challenged with sulfhydryl depleter compound, the gastroprotective action of both extracts was completely abolished. EDE had gastroprotective effect related to increase of glutathione bioavailability and stimulated higher levels of NO, H(2)O(2) and TNF-alpha production. Otherwise EDN showed better anti-Helicobacter pylori action than EDE. Neither extracts presented anti-inflammatory activity by oral route.Conclusion:The phytochemical investigation showed that both extracts possess phenolic acid derivatives, acylglycoflavonoids and condensed tannins with evident quantitative variations that probably influenced the pharmacological differences between extracts. Published by Elsevier B.V.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Can a Strychnos species be used as antiulcer agent? Ulcer healing action from alkaloid fraction of Strychnos pseudoquina St. Hil. (Loganiaceae)

Ethnopharmacological relevance: Strychnos pseudoquina St. Hil. (Loganiaceae) is one Brazilian native medicinal species described in the first edition of the Brazilian Official Pharmacopoeia in 1929. This medicinal plant, popularly known as quina-quina, quina-branca or casca aromatica was very commonly used in folk medicine in tea form obtained from the bark and/or leaves as tonic, antipyretic, antimalarial and mainly against diseases of the liver, spleen and stomach.Aim of the study: Previous study already characterized the gastroprotective action of this species The aim of the present study is to elucidate the mechanism of the healing process mediated by the methanolic extract (ME) and their enriched alkaloid fraction (EAF) from Strychnos pseudoquina in chronic gastric ulceration induced by 5% acetic acid in rats, an experimental model that accurately reflects human gastrointestinal disease.Material and methods: The ME and EAF was administered orally in a single dose (based on previously study of dose-response curve) for 14 days after chronic ulceration was induced in rats. The healing effect of ME and EAF was evaluated by macroscopic and morphometric analyses, immunohistochemical assay (PCNA and SOD) and anti-Helicobacter pylori effect was evaluated by in vitro assay.Results: Our results demonstrated that EAF significantly reduced border internal (42%) and external (38%) lesion area (mm(2)) by macroscopic analyses (P <0.05). Animals treated with EAF stimulated some proliferative factors by increasing the height of epithelial regenerative area and the expression of PCNA-positive nuclei. The number of vessels in gastric mucosa of rats treated with EAF reveals an expressive increase (4 times more than vehicle treatment) of vessels that stimulate cells proliferation in the healing region. These results suggest that the recovery of vascularization of the ulcerated area is involved in the healing action of alkaloid fraction of Strychnos pseudo quina. The MIC (minimum inhibitory concentration) of 75 mu g/ml from EAF showed an effective in vitro anti-Helicobacter pylori action of this fraction. EAF also was quite effective in the process of SOD release that is an important protective factor against bacterial agents. The efficacy of EAF was accomplished safely without presenting any alteration of toxicological parameters during 14 day of treatment.Conclusions: The expressive gastric healing effect by increasing cellular proliferation together with expression of SOD activity and antibacterial action against Helicobacter pylori confirm the efficacy of this species in heal gastric mucosa and these results are a important contribution to the knowledge of a crude drug presents at the Brazilian Official Pharmacopoeia since 1929. (C) 2011 Elsevier B.V. All rights reserved

The anti-ulcerogenic effects of Curatella americana L.

Ethnopharmacological relevance: Curatella americana L. (Dilleneaceae) is a medicinal plant very frequently cited as acting against gastrointestinal disorders in ethnopharmacological inventories of the Cerrado region of Brazil.Aim of the study:The ethanolic extract (CEB)and infusion (BI)of Curatella americana bark were investigated for their ability to prevent and heal ulceration of the gastric mucosa.Materials and methods: The preventive and healing actions of Curatella americana were evaluated in experimental in vivo models in rodents that simulated this disease in human gastric mucosa.Results: CEB significantly decreased the severity of gastric damage formation induced by the combination of several gastroprotective models (HCl/ethanol, indomethacin/bethanecol, absolute ethanol, stress and pylorus ligature). But, unlike CEB, the BI did not exert gastroprotective effect. The gastroprotective action of CEB involved antisecretory action, augmentation of gastric mucus (48%) and participation of endogenous sulfhydryl compounds that increase efficacy of barrier mucosa against injurious agents. CEB also presents effective healing action in chronic gastric disease (1.90 +/- 0.55 vs. 6.86 +/- 0.46 mm(2) in the control) and its action mechanisms consisted of increasing the PGE(2) (40%) and somatostatin levels (269%) while decreasing the gastrin level in rat plasma (79%).Conclusions: The gastroprotective effect and healing action of Curatella americana involved modulation of PGE2, somatostatin and gastrin levels, probably due to the presence of oligomeric and polymeric proanthocyanidins in the bark. (c) 2008 Elsevier B.V. All rights reserved.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Terminalia catappa L.: A medicinal plant from the Caribbean pharmacopeia with anti-Helicobacter pylori and antiulcer action in experimental rodent models

Ethnopharmacological relevance: Terminalia catappa L. (Combretaceae) is a medicinal plant listed as a pharmacopeia vegetable from Caribbean to treat gastritis. The objective of this study was to evaluate the gastroprotective and healing effect of the aqueous fraction (FrAq) obtained from the leaves of Terminalia catappa and to determine the antiulcer mechanism of action in experimental rodent models and its activity to Helicobacter pylori.Material and methods: In rodents, the FrAq was challenged by different necrotizing agents, such as absolute ethanol and ischemia-reperfusion injury. The antiulcer mechanism of action of FrAq was assessed and the healing effects of the fraction after seven and 14 days of treatment was evaluated by matrix metalloproteinase activity (MMP-2 and MMP-9). The toxicological effect of subacute treatment with FrAq during 14 days of treatment was also analyzed. The anti-Helicobacter pylori activity was determined by microdilution. The phytochemical study of the fraction was analyzed by experiments with FIA-ESI-IT-MSn (Direct Flow Analysis-ionization Electrospray Ion Trap Tandem Mass Spectrometry) and high performance liquid chromatography (HPLC) coupled to a photodiode array (PDA).Results: Oral treatment with FrAq (25 mg/kg) significantly decreased the number of ulcerative lesions induced by ethanol and ischemia/reperfusion injury. The action of FrAq was mediated by the activation of defensive mucosa-protective factors, such as increases in mucus production, the nitric oxide (NO) pathway and endogenous prostaglandins. Oral treatment with FrAq for seven and 14 days significantly reduced the lesion area (80% and 37%, respectively) compared to the negative control group. Analyses of MMP-9 and MMP-2 activity from gastric mucosa confirmed the accelerated gastric healing effect of FrAq. This extract also presented considerable activity against Helicobacter pylori. The mass spectrum and MS/MS of the aqueous fraction indicates the existence of many different phenolic compounds, including punicalagin, punicalin, and gallagic acid, among others.Conclusions: We concluded that FrAq from Terminalia catappa leaves has excellent preventive and curative effects on acute and chronic induced gastric ulcers and showed an important profile against Helicobacter pylori. (C) 2014 Elsevier Ireland Ltd. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES