Citral Modulates MMP-2 and MMP-9 Activities on Healing of Gastric Ulcers Associated with High-Fat Diet-Induced Obesity.

Obesity causes low-grade inflammation that results in the development of comorbidities. In people with obesity, exacerbation of gastric lesion severity and delayed healing may aggravate gastric mucosal lesions. Accordingly, we aimed to evaluate the citral effects on gastric lesion healing in eutrophic and obese animals. C57Bl/6 male mice were divided into two groups: animals fed a standard diet (SD) or high-fat diet (HFD) for 12 weeks. Gastric ulcers were induced using acetic acid (80%) in both groups. Citral (25, 100, or 300 mg/kg) was administered orally for 3 or 10 days. A vehicle-treated negative control (1% Tween 80, 10 mL/kg) and lansoprazole-treated (30 mg/kg) were also established. Lesions were macroscopically examined by quantifying regenerated tissue and ulcer areas. Matrix metalloproteinases (MMP-2 and -9) were analyzed by zymography. The ulcer base area between the two examined periods was significantly reduced in HFD 100 and 300 mg/kg citral-treated animals. In the 100 mg/kg citral-treated group, healing progression was accompanied by reduced MMP-9 activity. Accordingly, HFD could alter MMP-9 activity, delaying the initial healing phase. Although macroscopic changes were undetectable, 10-day treatment with 100 mg/kg citral exhibited improved scar tissue progression in obese animals, with reduced MMP-9 activity and modulation of MMP-2 activation.

Byrsonima intermedia A. Juss partitions promote gastroprotection against peptic ulcers and improve healing through antioxidant and anti-inflammatory activities.

Byrsonima intermedia is a species of bush popularly used to treat gastrointestinal disorders, such as gastric ulcers, gastritis, and diarrhea. Previous studies have revealed that the methanolic crude extract of B. intermedia leaves has gastroprotective and healing properties. In this new study, we specifically investigated two purified partitions, ethyl acetate (EtOAc) and water (AcoAq), obtained from the crude extract to characterize the antiulcer effects of these two partitions and the mechanisms of action of this medicinal plant. The healing effects of these partitions on the gastric and duodenal mucosa were assessed after ischemia-reperfusion (I/R) or acetic acid-induced injury. The involvement of tumor necrosis factor-alpha (TNF-alpha), interleukin 1ß (IL-1ß), interleukin 10 (IL-10), and myeloperoxidase (MPO) activity and glutathione (GSH) levels were determined. The antibacterial activity against Helicobacter pylori was evaluated using microdilution methods. The phytochemical analysis of AcoAq revealed a predominance of oligomeric proanthocyanidins and galloyl quinic esters, whereas EtOAc was found to contain concentrated flavonoids. Both partitions led to a significant reduction in gastric lesions, but AcoAq was more effective than EtOAc with regard to anti-Helicobacter pylori activity in addition to protecting the gastric mucosa against ethanol, non-steroidal anti-inflammatory drugs (NSAIDs) and duodenal mucosal damage induced by cysteamine. Additionally, both partitions were associated with a significant increase in gastric and duodenal healing and increased gastric mucosal GSH content after damage induced by acetic acid. On the other hand, after 6 days of treatment, EtOAc was more effective than AcoAq in ameliorating gastric damage upon initiation of the gastric I/R, which was accompanied by a significant reduction in the activity of gastric mucosal MPO, IL 1-ß and TNF-alpha, as well as an elevation in IL-10 and GSH content. These results demonstrate that the oligomeric proanthocyanidins and galloyl quinic esters present in AcoAq were more effective in the prevention of gastric and duodenal ulcers due to the antioxidant effects of these compounds, whereas the flavonoids present in EtOAc were more effective due to their anti-inflammatory activity on the gastric and duodenal tissue. All these results confirm that the rich phytochemical diversity of B. intermedia contributes to the pharmacological actions of this medicinal plant on the gastrointestinal tract in addition to its activity against H. pylori.

Can the gastric healing effect of Eugenia punicifolia be the same in male and female rats?

ETHNOPHARMACOLOGICAL RELEVANCE: Eugenia punicifolia (Kunth) DC. (Myrtaceae), an Amazonian medicinal plant known as "pedra-ume-caá," is popularly used as a natural remedy for inflammation, wounds, infections, diabetes, fever, and flu. Its anti-inflammatory, antinociceptive, and gastroprotective effects have already been characterized. We evaluated the gastric healing effect of the hydroalcoholic extract of the leaves of E. punicifolia (HEEP) in male and female Wistar rats against nonsteroidal anti-inflammatory drugs (NSAIDs) and ethanol. MATERIALS AND METHODS: The healing effect of HEEP on the gastric mucosa of adult male and female Wistar rats was measured after the chronic application of aggressive factors such as NSAIDs or 80% ethanol. Male, and intact and ovariectomized (OVZ) female rats were treated with HEEP for two days (NSAIDs) or one, two, four, and six days (80% ethanol). The stomachs were analyzed macroscopically for ulcerative lesions (mm2), and the healing process was measured using biochemical analysis with anti-inflammatory and antioxidant parameters. RESULTS: Macroscopic evaluation of the gastric mucosa showed that gastric lesions induced by NSAIDs were significantly healed (66%) and pro-inflammatory interleukin 5 cytokine level was decreased after two-day oral treatment with HEEP compared with those in the negative control group (p < 0.05). However, the gastric lesions induced by NSAIDs did not heal in HEEP-treated female rats (p > 0.05). In addition, four-day treatment with HEEP significantly healed the gastric lesions induced by ethanol in male and female rats (63% and 78%, respectively) compared to those of the negative control group (p < 0.05). However, the OVZ group required six days of HEEP treatment to heal gastric ulcers (67% compared to the control group). HEEP exerts the healing effect against ethanol by significantly reducing neutrophil infiltration into the gastric mucosa by decreasing myeloperoxidase activity in male and OVZ rats after four and six days of treatment, respectively (p < 0.05). Four-day treatment with HEEP also increased the level of a non-enzymatic antioxidant, reduced glutathione in intact females compared to that of the negative control group (p < 0.05). CONCLUSION: These findings indicated that HEEP was effective in promoting the healing of gastric ulcers induced by NSAIDs or ethanol. The gastric healing effects of this extract could be affected by female sex hormone interference; in future, comprehensive studies should be performed by considering sex differences.

Sex-specific effects of Eugenia punicifolia extract on gastric ulcer healing in rats.

AIM: To evaluate the sex-specific effects of a hydroalcoholic extract from Eugenia punicifolia (HEEP) leaves on gastric ulcer healing. METHODS: In this rat study involving males, intact (cycling) females, and ovariectomized females, gastric ulcers were induced using acetic acid. A vehicle, lansoprazole, or HEEP was administered for 14 d after ulcer induction. Body weight was monitored throughout the treatment period. At the end of treatment, the rats were euthanized and the following in vivo and in vitro investigations were performed: macroscopic examination of the lesion area and organ weights, biochemical analysis, zymography, and evaluation of protein expression levels. Additionally, the concentration-dependent effect of HEEP was evaluated in terms of subacute toxicity and cytotoxicity. RESULTS: Compared to the vehicle, HEEP demonstrated a great healing capacity by substantially reducing the ulcerative lesion area in males (52.44%), intact females (85.22%), and ovariectomized females (65.47%), confirming that HEEP accelerates the healing of acetic acid-induced gastric lesions and suggesting that this effect is modulated by female sex hormones. The antiulcer effect of HEEP was mediated by prostaglandin E2 only in male rats. Overall, the beneficial effect of HEEP was the highest in intact females. Notably, HEEP promoted the expression of vascular endothelial growth factor (intact vs ovariectomized females) and decreased the expression of Caspase-8 and Bcl-2 (intact female vs male or ovariectomized female). Additionally, HEEP enhanced fibroblast proliferation and migration into a wounded area in vitro, confirming its healing effect. Finally, no sign of subacute toxicity or cytotoxicity of HEEP was observed. CONCLUSION: In gastric ulcers, HEEP-induced healing (modulated by female sex hormones; in males, mediated by prostaglandin) involves extracellular matrix remodeling, with gastric mucosa cell proliferation and migration.

Cissus sicyoides: Pharmacological Mechanisms Involved in the Anti-Inflammatory and Antidiarrheal Activities.

The objective of this study was to evaluate the pharmacological mechanisms involved in anti-inflammatory and antidiarrheal actions of hydroalcoholic extract obtained from the leaves of Cissus sicyoides (HECS). The anti-inflammatory effect was evaluated by oral administration of HECS against acute model of edema induced by xylene, and the mechanisms of action were analysed by involvement of arachidonic acid (AA) and prostaglandin E2 (PGE2). The antidiarrheal effect of HECS was observed and we analyzed the motility and accumulation of intestinal fluid. We also analyzed the antidiarrheal mechanisms of action of HECS by evaluating the role of the opioid receptor, α2 adrenergic receptor, muscarinic receptor, nitric oxide (NO) and PGE2. The oral administration of HECS inhibited the edema induced by xylene and AA and was also able to significantly decrease the levels of PGE2. The extract also exhibited significant anti-diarrheal activity by reducing motility and intestinal fluid accumulation. This extract significantly reduced intestinal transit stimulated by muscarinic agonist and intestinal secretion induced by PGE2. Our data demonstrate that the mechanism of action involved in the anti-inflammatory effect of HECS is related to PGE2. The antidiarrheal effect of this extract may be mediated by inhibition of contraction by acting on the intestinal smooth muscle and/or intestinal transit.

The Anti-Inflammatory Effects of the Methanolic Extract and Fractions from Davilla elliptica St. Hil. (Dilleniaceae) on Bothrops jararaca Envenomation.

Inflammation and haemorrhage are the main characteristics of tissue injury in botropic envenomation. Although some studies have shown that anti-venom prevents systemic reactions, it is not efficient in preventing tissue injury at the site of the bite. Therefore, this work was undertaken to investigate the anti-inflammatory effects of the methanolic extract and fractions from D. elliptica and to evaluate the role of matrix metalloproteinases (MMPs) in this process. Effects of the extract and fractions from D. elliptica were evaluated using a carrageenan-induced paw oedema model in rats, and leukocyte rolling was visualized by intravital. The quantification of MMPs activities (MMP-2 and MMP-9) extracted from the dermis of mice treated with extract and fractions alone or incubated with venom was determined by zymographic analyses. Our results show that intraperitoneal (i.p.) injection of fractions significantly reduced paw oedema after the carrageenan challenge. Treatment with the tannins fraction also resulted in considerable inhibition of the rolling of leukocytes and this fraction was able to decrease the activation of MMP-9. These results confirmed the anti-inflammatory activity of the methanolic extract and tannins fraction of D. elliptica and showed that the dermonecrosis properties of B. jararaca venom might be mediated through the inhibition of MMP-9 activity.

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.

ETHNOPHARMACOLOGICAL RELEVANCE: Serjania marginata (Sapindaceae), a medicinal plant commonly found in the Brazilian Cerrado, Paraguay, Bolivia and Argentina, is also known as "cipó-uva" or "cipó-timbó". Ethnopharmacological studies indicate that the leaves from this medicinal plant are used in folk medicine to treat gastric pain. The overall objective of this study was to evaluate the gastroprotective and healing effect of the hydroalcoholic extract obtained from S. marginata (HESM) leaves using rodent experimental models. As part of the integrative study of this medicinal plant, we also evaluated the acute toxicity, antimicrobial, antidiarrheal, (anti)mutagenic, and hemodynamic effects. MATERIAL AND METHODS: We performed a pharmacological study to test the acute toxicity and antimutagenic effect (Ames assay) of the HESM. The HESM was tested against different necrosis-promoting agents and experimental manipulations, such as absolute ethanol, cysteamine, pyloric ligature, and ischemia-reperfusion (I/R) injury. The gastroprotective effect of the HESM was assessed by analyzing the gastric juice (volume, pH, total acidity) and the mucus in the gastric mucosa from rats. We assessed the levels of NO, sulfhydryl compounds, PGE2, vanilloid receptor, glutathione (GSH), and malondialdehyde (MDA), as well as the myeloperoxidase (MPO) activity. The gastric healing effects of the HESM were evaluated during 7 or 14 days of treatment. The intestinal motility, antidiarrheal action, and antibacterial effects (microdilution methods) of the HESM were also evaluated. RESULTS: The phytochemical analysis of the HESM revealed the presence of saponins, flavonoid glycosides, and tannins. The extract exhibited no sign of acute toxicity or mutagenic effect in vitro. In contrast, this extract exhibited a protective effect against the mutagenic action of direct- and indirect-acting mutagens. Only the oral administration of HESM (250mg/kg) significantly decreased the severity of gastric damage induced by ethanol (60.13%) and I/R (58.31%). The HESM exerts its gastroprotective effects by decreasing the MPO and MDA activities in the gastric tissue and by increasing the amount of adherent mucus covering the gastric mucosa. In vitro, the extract also displayed evident antimicrobial effects against Helicobacter pylori. However, the preventive effect of the HESM was not accompanied by an ulcer-healing effect. The treatment with HESM (14 days) significantly increased gastric lesions in 99% of the tested animals compared with the control group. This result represents a highly relevant piece of evidence that should resonate as an alert against the chronic use of this medicinal plant as an antiulcer in folk medicine. CONCLUSIONS: Despite the anti-H. pylori and gastroprotective actions of S. marginata in experimental models, the gastric injuries aggravation induced after chronic treatment with the HESM argues against the use of this plant species in folk medicine.

Geraniol-a flavoring agent with multifunctional effects in protecting the gastric and duodenal mucosa.

Geraniol is an acyclic monoterpene alcohol commonly used as a flavoring agent. The present study was undertaken to investigate antiulcerogenic effects of geraniol and to determine the possible mechanisms involved in this action. In the model of the ethanol-induced ulcer, treatment of rats with geraniol by oral route significantly inhibited gastric lesions by 70 % (7.50 mg/kg) to 99 % (200 mg/kg). Analysis of the gastric tissue of rats treated with geraniol (7.50 mg/kg) revealed that total glutathione content levels (GSH) increased and levels of myeloperoxidase (MPO) decreased in the gastric mucosa. Oral treatment with geraniol significantly decreased the number of ulcerative lesions induced by ischemia/reperfusion injury by 71 % and the duodenal ulcers induced by cysteamine by 68 %. The action of geraniol was mediated by the activation of defensive mucosa-protective factors such as the nitric oxide (NO) pathway, endogenous prostaglandins, increased mucus production, increased sulfhydryl compounds, antioxidant properties and the stimulation of calcitonin gene-related peptide (CGRP) release through the activation of transient receptor potential vanilloid (TRPV). The multifaceted gastroprotective mechanisms of geraniol represent a promising option for the treatment of gastric and duodenal mucosa injury.

Antidiarrheal and intestinal antiinflammatory activities of a methanolic extract of Qualea parviflora Mart. in experimental models.

ETHNOPHARMACOLOGICAL RELEVANCE: An ethnopharmacological survey indicated that the bark from Qualea parviflora Mart. (Vochysiaceae) could be used to treat gastrointestinal disorders, such as diarrhea and intestinal inflammation. The objective of this study was to evaluate the effects of a methanolic extract from the bark of Qualea parviflora (QP) in an experimental model of diarrhea and intestinal inflammation induced in rodents. MATERIAL AND METHODS: The antidiarrheal and antispasmodic effects of QP were investigated by measuring intestinal motility, diarrhea, and intestinal fluid accumulation in rodents after challenging with a cathartic agent. In addition, the effects of QP on the contractility of the isolated mice-ileum preparation were determined. Acute intestinal inflammation was induced in male Wistar rats by the rectal administration of trinitrobenzenesulfonic acid (TNBS) in 50% ethanol (0.25 mL). QP was administered orally (for 5 days) prior to the induction of inflammation. The colonic injury and extent of inflammation were assessed by macroscopic damage scores and lesion length. The enhanced colonic mucosal injury, inflammatory response, and oxidative stress were evaluated by myeloperoxidase (MPO) activity; the tumor necrosis factor alpha (TNF-α), interleukin 1ß (IL1-ß), and malondialdehyde (MDA) levels; and the glutathione (GSH) content. RESULTS: Oral treatment with QP (500 mg/kg) delayed the onset of diarrhea, reduced the amount of liquid stool, and decreased the severity of the diarrhea and the evacuation index in rodents challenged with castor oil (p<0.01). Additionally, QP (150-500 µg/mL) demonstrated effective antispasmodic activity against carbachol-induced contractions of mouse ileum in vitro. Oral treatment (25 and 50 mg/kg/day) with QP significantly reduced the intestinal inflammation induced by TNBS in rats (52% and 45%, respectively). Improvement of colonic mucosal injury by treatment with QP was demonstrated by a decrease in MDA levels and an increase in GSH content in colonic tissue. QP also prevented intestinal inflammation as evidenced by reduced cytokine levels (TNF-α and IL1-ß) and low MPO activity. CONCLUSIONS: The ethnopharmacological usefulness of the bark from Qualea parviflora against diarrhea containing blood and mucus was supported by the observed antidiarrheal, antispasmodic, and intestinal antiinflammatory properties of this medicinal plant.

Qualea parviflora Mart.: an integrative study to validate the gastroprotective, antidiarrheal, antihemorragic and mutagenic action.

ETHNOPHARMACOLOGICAL RELEVANCE: Qualea parviflora Mart. is a medicinal species commonly found in the Brazilian Cerrado biome. AIM OF THE STUDY: Based on ethnopharmacological data, methanolic extract from Qualea parviflora (QP) bark was evaluated for its antiulcer, analgesic, anti-hemorrhagic, mutagenic and anti-Helicobacter pylori activities. MATERIAL AND METHODS: The gastroprotective action of the extract was evaluated in rodent experimental models (HCl/ethanol, ethanol or NSAID). We also evaluated mutagenic effect (Ames assay), anti-Helicobacter pylori, anti-hemorrhagic action, analgesic and inflammatory effects (hot-plate test and carrageenin-induced hind paw edema) of methanolic extract from Qualea parviflora. RESULTS: QP (500 mg/kg, p.o.) was able to protect gastric mucosa against HCl/ethanol solution (77%), absolute ethanol (97%), and also against injurious effect of NSAID (36%). When QP was challenged with sulfhydryl depletor compound, the gastroprotective action of extract was abolished. QP treatment was able to maintain the GSH level and show a concentration-dependent inhibition effect on the lipid peroxidation. QP present anti-Helicobacter pylori effect (MIC=75 microg/mL), anti-hemorrhagic and antidiarrheal action but not present analgesic or anti-inflammatory effect. CONCLUSION: methanolic extract from Qualea parviflora had gastroprotective effect related to the increase of gastric mucosa defensive factors such PGE(2) levels and maintain the basal gastric glutathione levels. The methanolic extract also showed anti-Helicobacter pylori activity, anti-hemorrhagic effect and antioxidant action, but absence of analgesic, mutagenic and toxic effects, a profile that adds safety to its use.

Evaluation of Strychnos pseudoquina ST. HIL. leaves extract on gastrointestinal activity in mice.

Strychnos pseudoquina ST. HIL. (Loganiaceae) was investigated for its ability to protect the gastric mucosa against injuries caused by non-steroidal anti-inflammatory drugs (piroxicam) and a necrotizing agent (HCl/EtOH) in mice. The MeOH extract and enriched alkaloidic fraction (EAF) provided significant protection in experimental models wheer used at doses of 250 and 1000 mg/kg. In vivo tests were carried out to evaluate for possible toxic effects and no mortality was observed up to the 5 g/kg dose level. Phytochemical investigation led to the isolation of a new indole alkaloid, which elucidated the observed pharmacological effects.