Mechanism(s) of action involved in the gastroprotective activity of Muntingia calabura

Pharmacological insight of rutin as a potential candidate against peptic ulcer

Peptic ulcer is a sore on the stomach lining that results from the erosion of the gastrointestinal tract mucosa due to various influencing factors. Of these, Helicobacter pylori infection and non-steroidal anti-inflammatory drugs (NSAIDs) stand out as the most prominent causes. This condition poses a significant global health concern due to its widespread impact on individuals worldwide. While various treatment strategies have been employed, including proton pump inhibitors and histamine-2 receptor antagonists, these have notable side effects and limitations. Thus, there is a pressing need for new treatments to address this global health issue. Rutin, a natural flavonoid, exhibits a range of biological activities, including anti-inflammatory, anticancer, and antioxidant properties. This review explores the potential anti-ulcer effect of rutin in experimental models and how rutin can be a better alternative for treating peptic ulcers. We used published literature from different online databases such as PubMed, Google Scholar, and Scopus. This work highlights the abundance of rutin in various natural sources and its potential as a promising option for peptic ulcer treatment. Notably, the anti-inflammatory properties of rutin, which involve inhibiting inflammatory mediators and the COX-2 enzyme, are emphasized. While acknowledging the potential of rutin, it is important to underscore the necessity for further research to fully delineate its therapeutic potential and clinical applicability in managing peptic ulcers and ultimately improving patient outcomes. This review on the anti-ulcer potential of rutin opened a new door for further study in the field of alternative medicine in peptic ulcer management.

Comprehensive insights on treatment modalities with conventional and herbal drugs for the treatment of duodenal ulcers

Areas of the body accessible to gastric secretions, such as the stomach and duodenum, are most commonly damaged by circumscribed lesions of the upper gastrointestinal tract mucosa. Peptic ulcer disease is the term for this illness (PUD). About 80% of peptic ulcers are duodenal ulcers, with stomach ulcers accounting for the remaining 20%. Duodenal ulcers are linked to the two primary results about Helicobacter pylori infection and COX inhibitor users. Additional causes might include drinking, smoking, stress, and coffee consumption. The indications and symptoms of a duodenal ulcer depend on the patient's age and the lesion's location. For duodenal ulcers, proton pump inhibitors (PPIs) are the usual course of treatment. This comprehensive study included an in-depth literature search in the literature and methods section using electronic databases such as PubMed, ScienceDirect, and Google Scholar. The search method included publications published from the inception of the relevant database to the present. Inclusion criteria included studies investigating different treatment options for duodenal ulcer disease, including traditional pharmacotherapy and naturopathic treatments. Data mining includes information on treatment techniques, treatment outcomes, and possible synergies between conventional and herbal treatments. In addition, this review critically examines the available information on the effectiveness, safety, and possible side effects of different treatments. The inclusion of conventional and herbal treatments is intended to provide a comprehensive overview of the many treatment options available for duodenal ulcer disease. A more comprehensive and personalized treatment plan can be achieved by incorporating dietary changes, lifestyle modifications, and, if necessary, herbal therapies to complement other treatments normally.

Gastroprotective Activities of Aqueous and 80% Methanol Leaf Extracts of Stephania abyssinica (Quart.-Dill. and A. Rich.) Walp. (Menispermaceae) in Rats

Background

An ethnobotanical study showed that the leaf of Stephania abyssinica (S. abyssinica) is used for the treatment of gastritis, but there is no scientific investigation.

Objective

The aim of this study was to evaluate the gastroprotective activities of both aqueous and 80% methanol leaf extracts of S. abyssinica in experimental rats.

Methods

Decoction and maceration techniques were used to prepare aqueous and 80% methanol leaf extracts, respectively. The extracts were evaluated against pyloric ligation, indomethacin, and ethanol-induced gastric ulcer models at doses of 100, 200, and 400 mg/kg. Negative control received 2% tween 80, while positive controls received 20 mg/kg of omeprazole and 100 µg/kg of misoprostol. Parameters, such as ulcer index, gastric mucin content, gastric juice volume, pH, and free and total acidity were measured.

Results

In the pyloric ligation induced gastric ulcer model, all doses of both extracts significantly reduced the ulcer index and gastric juice volume, while doses of 200 and 400 mg/kg exhibited a significant increment in mucus content and gastric juice pH as well as decrease in free and total acidity as compared to negative control. In indomethacin and ethanol induced gastric ulcer models, pretreatment with both extracts significantly reduced the ulcer index and enhanced gastric mucin content in a dose-dependent manner. Phytochemical screening of both extracts showed the existence of flavonoids, phenols, tannins, saponins, alkaloids, and coumarins with high contents of phenols, flavonoids, and alkaloids in 80% methanol extract.

Conclusion

This study revealed that aqueous and 80% methanol leaf extracts of S. abyssinica possessed remarkable gastroprotective activities against experimentally induced gastric ulcer models, and this possibly justify the traditional use of S. abyssinica leaves to treat gastritis.

Alloimperatorin from Ammi majus fruits mitigates Piroxicam-provoked gastric ulcer and hepatorenal toxicity in rats via suppressing oxidative stress and apoptosis

Introduction: Fruits of Ammi majus, commonly called bishop's weed, contain a significant amount of furanocoumarins. Alloimperatorin (Allo, 6) was isolated from the free coumarin fraction of fruits, beside 8-hydroxypsoralen (1), methoxsalen (2), heraclin (3), isoimperatorin (4), imperatorin (5), isoheraclenin (7) and heraclenin hydrate (8). Piroxicam (Px) is a widely used pain-relieving drug that demonstrated side effects, including gastric ulceration and hepatorenal toxicity.Objective: This study aimed to investigate the protective potential of Alloimperatorin against Px-induced gastric ulceration and hepatorenal toxicity.Material & Methods: Rats were divided into four groups: Negative control, Px-induced rats, Allo + Px co-treated group, and Pc + Px co-treated group. Allo (25 mg/kg body weight) and Pc (25 mg/kg body weight) treatments were received 5 days before and 4 days after Px intoxication for 4 days (50 mg/kg body weight). Serum prostaglandin E2 (PG-E2) and liver and kidney functions were measured. Oxidative stress markers were evaluated in the three tissues. Histopathological features and caspase-3 immunoexpression were monitoredResults & Discussion: Px triggered gastric ulceration, increased indices of liver and kidney functions, decreased PG-E2 levels, provoked oxidative stress, and activated caspase-3 immunoexpression. Co-treatment with Allo demonstrated protective activities.Conclusion: Alloimperatorin exhibited anti-oxidative, anti-inflammatory, and anti-apoptotic activities.

Effects of ethanolic extracts of Quercus, Cirsium vulgare, and Falcaria vulgaris on gastric ulcer, antioxidant and inflammatory indices, and gene expression in rats

INTRODUCTION

Gastric ulcer is a multifaceted process and is usually caused by mucosal damage. Herbal medicines have received much attention considering the side effects of chemical drugs. Nowadays, the use of herbal medicines has received much attention considering the side effects of chemical drugs. Quercus brantii Lindl, Cirsium vulgare (Savi) Ten, and Falcaria vulgaris Bernh are plants used as traditional phytomedicine for gastric ulcer diseases.

AIM OF THE STUDY

This study was aimed to investigate the protective effects of hydroalcoholic extracts of these herbs on ethanol-induced gastric ulceration, in addition, to investigate the antioxidant, anti-inflammatory, and gene expression.

MATERIALS AND METHODS

Thirty Sprague Dawley rats, (200-250 g), were divided into six groups: Control: intact animals; sham: gavaged with distilled water (14 days); negative control: gavaged with 20 mg/kg of omeprazole (14 days); experimental groups I, II, and III: gavaged with 500 mg/kg of the extract of Falcaria vulgaris, Quercus brantii, and Cirsium vulgare, respectively, (14 days). The number of ulcers and pathological parameters were assessed. The serum superoxide dismutase, catalase, glutathione peroxidase, malondialdehyde, total antioxidant capacity, albumin, total protein, haptoglobin, alpha-1-acid glycoprotein, total globulin, alpha-2-macroglobulin, C-fos, C-myc, and Caspase-9 were measured by ELISA and RT-PCR.

RESULTS

The extracts significantly reduced gastric ulcer (52.33%). The results showed that the Quercus brantii extract was more effective. There were significant differences between the serum levels of alpha-1-acid glycoprotein and those of alpha-2-macroglobulin. Also, there was a significant difference in the serum level of antioxidant parameters. Changes in the expression of the genes also confirmed the results suggested by other parameters. The expression levels of C-fos, C-myc, and caspase-9 were decreased, but the Bcl-2 expression increased.

CONCLUSION

The hydro-alcoholic extracts revealed various protection and noticeable change in the expression of caspase-9, C-myc, C-fos, and Bcl-2 genes in rats.

Iranian plant Eremurus persicus: an overview of botany, traditional uses, phytochemistry and pharmacology

Eremurus persicus (Jaub. & Spach) Boiss. commonly known as "Serish" is a valuable ornamental plant with culinary uses and also utilized in traditional medicine for treating Gastrointestinal diseases. This comprehensive study was performed to investigate the pharmacological and biological effects of E. persicus and the compounds identified and isolated from it in order to encourage researchers to study it further. Despite the few number of studies on the ethnopharmacology of the plant E. persicus, however studies conducted on either crude extracts, solvent fractions or isolated pure compounds from E. persicus a varied range of biological effects comprising antibacterial, anti-fungal, anti-diabetic and etc. have reported. Phytochemical analysis of different parts of E. persicus unveiled 52 phytochemicals. However, the toxicity of this plant and its ethnopharmacological claims should be thoroughly investigated.

Sphaeranthus senegalensis DC: Evaluation of chemical constituents, oral safety, gastroprotective activity, and mechanism of action of its hydroethanolic extract

ETHNOPHARMACOLOGICAL RELEVANCE

Sphaeranthus senegalensis DC is a seasonal herb with a spicy smell that grows wild in wet grounds of tropical Africa and Asia. The plant is used in folk medicine for the treatment of various diseases; that includes its use to treat gastric ulcers.

AIM OF THE STUDY

This study aimed to investigate the chemical constituents of the hydroethanolic extract of Sphaeranthus senegalensis DC and evaluate its oral safety, gastroprotective activity, and mechanisms of action using laboratory models in rats and mice.

MATERIALS AND METHODS

Hydroethanolic extract (70%) of the powdered whole dried material was prepared, and chemical constituents of the resultant extract (denoted HESs) standardized using the high-performance liquid chromatography (HPLC) method. The safety profile of HESs was assessed using 2000 mg/kg, oral (p.o.) for Hippocratic screening in mice, and 800 mg/kg, p.o. for 28 days subchronic toxicity assay in rats. The gastroprotective effect of HESs (25, 100, and 400 mg/kg, p.o.) was investigated using acidified ethanol, piroxicam, water immobilization stress, and acetic acid-induced ulcer models. The gastroprotective mechanisms of HESs were evaluated using its effect on gastric mucus protection, nitric oxide modulation, gastric juice secretory parameters, catalase and myeloperoxidase activities. Histological analysis of the stomach tissues was also carried out.

RESULTS

The HPLC analysis indicated the presence of 25.94% phenolics (gallic acid, caffeic acid, and ferulic acid) and 14.53% flavonoids (rutin, morin, luteolin, quercetin, and apigenin). Hippocratic screening and the 28 days subchronic study indicated that HESs is generally safe. Result shows that oral administration of HESs (25, 100 and 400 mg/kg) alleviated the severity of the gastric ulcers induced by acidified ethanol by 35.65% (p < 0.05), 48.70% (p < 0.05) and 78.02% (p < 0.001) respectively; exhibited gastroprotective effect against the gastric lesions induced by piroxicam by 37.97% (p < 0.05), 53.27% (p < 0.05) and 76.23% (p < 0.001) respectively; and decreased the severity of the water immobilization stress-induced gastric ulcers by 32.43% (p < 0.05), 55.26% (p < 0.01) and 74.05% (p < 0.001) respectively, when compared to the vehicle control group. The mechanisms of action assays indicated that the gastroprotective activity was mediated mainly through gastroprotection, antisecretory, and antioxidant activities. Histological analysis showed it inhibited epithelial cell loss, vascular damage, and leucocyte infiltration.

CONCLUSION

HESs contains useful phytochemicals, is safe, and exhibited significant gastroprotective action. The results provided justification for its claim in the treatment of gastric ulcers and its evaluation for potential application as a gastroprotective agent.

Metabolite variations and antioxidant activity of Muntingia calabura leaves in response to different drying methods and ethanol ratios elucidated by NMR-based metabolomics

INTRODUCTION

Muntingia calabura from the Muntingiaceae family has been documented for several medicinal uses. The combinations of drying treatment and extracting solvents for a plant species need to be determined and optimised to ensure that the extracts contain adequate amounts of the bioactive metabolites.

OBJECTIVE

Evaluate the metabolite variations and antioxidant activity among M. calabura leaves subjected to different drying methods and extracted with different ethanol ratios using proton nuclear magnetic resonance (¹ H-NMR)-based metabolomics. Methodology The antioxidant activity of M. calabura leaves dried with three different drying methods and extracted with three different ethanol ratios was determined by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO) scavenging assays. The metabolites variation among the extracts and correlation with antioxidant activity were analysed by ¹ H-NMR-based metabolomics.

RESULTS

Muntingia calabura leaves extracted with 50% and 100% ethanol from air-drying and freeze-drying methods had the highest total phenolic content and the lowest IC₅₀ value for the DPPH scavenging activity. Meanwhile, oven-dried leaves extracted with 100% ethanol had the lowest IC₅₀ value for the NO scavenging activity. A total of 43 metabolites, including sugars, organic acids, amino acids, phytosterols, phenolics and terpene glycoside were tentatively identified. A noticeable discrimination was observed in the different ethanol ratios by the principal component analysis. The partial least-squares analysis suggested that 32 compounds out of 43 compounds identified were the contributors to the bioactivities.

CONCLUSION

The results established set the preliminary steps towards developing this plant into a high value product for phytomedicinal preparations.

Gastroprotective Effects of Inulae Flos on HCl/Ethanol-Induced Gastric Ulcers in Rats

Inulae Flos, the flower of Inula britannica L., is used as a dietary supplement, beverage, and medicine in East Asia. In this study, we evaluated the gastroprotective effects of Inulae Flos extract (IFE) against gastric mucosal lesions induced by hydrochloric acid (HCl)/ethanol in rats and explored its potential mechanisms by measuring antioxidant enzyme activity, mucus secretion, and prostaglandin E₂ (PGE₂) levels. Pretreatment with IFE at doses of 100 and 300 mg/kg significantly inhibited gastric lesions in HCl/ethanol-treated rats. IFE increased the activities of superoxide dismutase and catalase and the levels of glutathione and PGE₂ in gastric tissues. The administration of IFE also significantly increased the gastric wall mucus contents in HCl/ethanol-induced gastric lesions. These findings suggest that IFE has gastroprotective effects against HCl/ethanol-induced gastric lesions and exerts these effects through increased antioxidant levels and gastric mucus secretion. Inulae Flos may be a promising agent for the prevention and treatment of gastritis and gastric ulcers.

Medicinal Plants in the Treatment of Peptic Ulcer Disease: A Review

Peptic Ulcer Disease (PUD) is the most common disorder of the stomach and duodenum, which is associated with Helicobacter pylori infection. PUD occurs due to an imbalance between offensive and defensive factors and Proton Pump Inhibitors (PPI), Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) and antibiotics are frequently used for the treatment. Recently, medicinal plants have emerged as efficacious, safe and widely available alternative therapies for PUD. The aim of this review was to study the medicinal plants and phytochemicals, which have been used for PUD treatment to evaluate the potential role of natural compounds to develop herbal remedies for PUD. Information was obtained using a literature search of electronic databases, such as Web of Science, Google Scholar, PubMed, Sci Finder, Reaxys and Cochrane. Common and scientific names of the plants and keywords such as 'peptic ulcer', 'gastric ulcer', 'stomach ulcer' and 'duodenal ulcer' were used for search. Eventually, 279 plants from 89 families were identified and information on the plant families, part of the plant used, chemical constituents, extracts, ulcer model used and dosage were abstracted. The results indicated that most of the anti-PUD plants were from Asteraceae (7.1%) and Fabaceae (6.8%) families while flavonoids (49%), tannins (13%), saponins (10%) and alkaloids (9%) were the most common natural compounds in plants with anti-PUD activity.

UPLC-qTOF-MS Phytochemical Profile and Antiulcer Potential of Cyperus conglomeratus Rottb. Alcoholic Extract

Cyperus has been commonly used as a multi-use medicinal plant in folk medicine worldwide. The objectives of our study were to determine the different metabolites in the Cyperus conglomeratus Rottb. methanol extract, and to assess its in vivo gastroprotective effect in ethanol-induced gastric ulcer model in rats. Serum levels of galactin-3 and TNF-α were employed as biochemical markers. To pinpoint for active agents, comprehensive metabolites profiling of extract via UPLC-qTOF-MS/MS was employed. A total of 77 chromatographic peaks were detected, of which 70 were annotated. The detected metabolites were categorized into phenolic acids and their derivatives, flavonoids, stilbenes, aurones, quinones, terpenes, and steroids. Rats were divided into six groups; healthy control, ulcer control, standard drug group, and 25, 50, 100 mg/kg of C. conglomeratus treated rats. Pre-treatment with C. conglomeratus alcohol extract significantly reduced galactin-3, and TNF-α in ethanol-induced ulcer model at 25, 50, and 100 mg/kg. Further histopathological and histochemical studies revealed moderate erosion of superficial epithelium, few infiltrated inflammatory cells, and depletion of gastric tissue glycoprotein in the ulcer group. Treatment with the extract protected the gastric epithelial cells in a dose-dependent manner. It could be concluded that C. conglomeratus extract provides significant gastroprotective activity in ethanol-induced gastric ulcer and ought to be included in nutraceuticals in the future for ulcer treatment.

Evaluation of Gastroprotective Activity of Linoleic acid on Gastric Ulcer in a Mice Model

BACKGROUND

Gastric ulcer has been a major cause of morbidity and mortality worldwide, and it has been linked to factors such as nutritional deficiency, smoking, stress, and continuous intake of non-steroidal anti-inflammatory drugs (NSAIDs). The search for new anti-ulcer therapeutic agents has been the subject of several studies. Recently, the gastroprotective effect of Celtis iguanaea has been reported, with linoleic acid (LA) responsible for many of the therapeutic effects of this medicinal plant.

AIM

This study aims to investigate the gastroprotective activity and the possible mechanisms in which LA may be involved, through different experimental assays in mice.

METHODS

The gastroprotective activity LA was evaluated in the ulcer induced by indomethacin, HCl/EtOH, hypothermicrestraint stress and pyloric ligation. For the gastroprotective mechanisms investigation the quantification of the volume (mL), pH and total acidity of gastric secretion were considered.

RESULTS

The oral administrations of 25 mg/kg, 50 mg/kg or 100 mg/kg of body weight of LA were capable of protecting the gastric mucosa against HCl/ethanol (10 mL/kg p.o.), and oral administrations of 50 mg/kg LA showed protection from ulcers induced by indomethacin, hypothermic-restraint stress and pyloric ligation.

CONCLUSION

The results of this study show the gastroprotective role of LA in gastric mucosal damage induced by all assayed distresses. The observed gastroprotection possibly occurs due to the mediated increase of mucosal defensive factors.

Methanol extract of Muntingia calabura leaves attenuates CCl4-induced liver injury: possible synergistic action of flavonoids and volatile bioactive compounds on endogenous defence system

CONTEXT

Muntingia calabura L. (Muntingiaceae) exerts antioxidant and anti-inflammatory activities, thus, it might be a good hepatoprotective agent.

OBJECTIVE

This study investigates the effect of methanol extract of M. calabura leaves (MMCL) on hepatic antioxidant and anti-inflammatory activities in CCl₄-induced hepatotoxic rat.

MATERIALS AND METHODS

Sprague Dawley rats (n = 6) were treated (p.o.) with 10% DMSO (Groups 1 and 2), 50 mg/kg N-acetylcysteine (Group 3) or, 50, 250, or 500 mg/kg MMCL (Groups 4-6) for 7 consecutive days followed by pretreatment (i.p.) with vehicle (Group 1) or 50% CCl₄ in olive oil (v/v) (Groups 2-6) on day 7th. Plasma liver enzymes and hepatic antioxidant enzymes and pro-inflammatory cytokines concentrations were measured while liver histopathology was examined.

RESULTS

MMCL, at 500 mg/kg, significantly (p < 0.05) ameliorated CCl₄-induced hepatotoxicity by decreasing the plasma level of alanine transaminase (429.1 versus 168.7 U/L) and aspartate transaminase (513.8 versus 438.1 U/L) as well as the tissue level of nitric oxide (62.7 versus 24.1 nmol/g tissue). At 50, 250, or 500 mg/kg, MMCL significantly (p < 0.05) reduced the tumour necrosis factor α (87.8 versus 32.7 pg/mg tissue), interleukin-1β (1474.4 versus 618.3 pg/mg tissue), and interleukin-6 (136.7 versus 30.8 pg/mg tissue) while increased the liver catalase (92.1 versus 114.4 U/g tissue) and superoxide dismutase (3.4 versus 5.5 U/g tissue). Additionally, qualitative phytochemicals analysis showed that MMCL contained gallic acid, ferulic acid, quercetin, and genistein.

DISCUSSION AND CONCLUSIONS

MMCL ability to attenuate CCl₄-induced hepatotoxicity could be helpful in the development of hepatoprotective agents with fewer side effects.

Gastroprotective and anti-inflammatory effects of Prunus cerasus phytochemicals and their possible mechanisms of action

Prunus cerasus (P. cerasus) is an alternative-medicine used traditionally for amelioration of chronic-ailments marked by elevation in oxidative-stress like neuropathy. The oxidative-stress control was reported to ameliorate the inflammatory-process. This study aimed to phytochemically-investigate P. cerasus most-active phytochemicals utilizing in-vivo biological models to explore their gastroprotective, anti-inflammatory, and antinociceptive potentials and their possible mechanisms of action. Sonication with EtAc was used to extract P. cerasus fruit (Scf), and seed (Scs). The phytochemical-investigation of Scf was performed by RP-HPLC, while that of Scs was explored utilizing GC-FID. A bio-guided-fraction and isolation method was done utilizing column-chromatography, and have shown that cyanidin-3-glucoside (Cy3G) was the most-active constituent in Scf, while linoleic-acid (LA) was the most-active constituent in Scs. Scf, Scs, Cy3G, and LA significantly (p ˂ 0.05) protected the gastric-mucosa against HCl/EtOH-induced gastric-lesions. Scs (200 mg/kg) has shown the most gastroprotective-potentials, and had comparable-results to ranitidine (50 mg/kg). Scf, Scs, Cy3G, and LA have shown significant anti-inflammatory and antinociceptive potentials against carrageenan induced-edema and nociceptive-pain, respectively, where Scs (200 mg/kg) has shown the most anti-inflammatory and antinociceptive potentials, and had comparable results to ibuprofen (100 mg/kg). Scf, Scs, Cy3G, and LA have counter-acted carrageenan-induced oxidative-stress markers, with increased serum-catalase and reduced-glutathione levels, and decreased lipid-peroxidation. Histopathological-studies demonstrated gastroprotective potentials, regeneration and improvement of the spleen-structural architecture when treated with highest doses of Scs and Scf. The reduction of the pro-inflammatory TNF-alpha and IL-6, and elevation the anti-inflammatory factor IL-10 levels, spleen regenerative-capacity and oxidative-stress amelioration might be the main-mechanism responsible for P. cerasus anti-inflammatory potentials. P. cerasus appears to aid in ameliorating the inflammatory process, and reducing pain-thresholds while preserving the stomach.

Gastroprotective Effects of Paeonia Extract Mixture HT074 against Experimental Gastric Ulcers in Rats

Background

Paeonia extract mixture HT074 is a standardized multiherbal mixture comprising extracts from Inula britannica flowers and Paeonia lactiflora roots, which are used to treat digestive disorders in traditional Korean medicine. This study was focused on elucidating the underlying mechanisms of the gastroprotective effects of HT074 in different gastric ulcer models.

Methods

Gastric lesions were induced in rats by an HCl/EtOH solution, water immersion-restraint stress (WIRS), and indomethacin. Gastric secretions were studied in pylorus-ligated rats, while mucus secretions were assessed by measuring alcian blue-binding capacity of mucus in the rat model of HCl/EtOH-induced gastric ulcer. Additionally, the involvement of nitric oxide (NO) and sulfhydryl compounds in HT074-mediated mucosal protection was elucidated using their inhibitors, i.e., N^G-nitro- _L-arginine methyl ester hydrochloride (L-NAME) and N-ethylmaleimide (NEM), respectively. Furthermore, the effects on indomethacin-induced cell death and prostaglandin E₂ (PGE₂) levels were assessed in AGS cells.

Results

Oral administration of HT074 significantly decreased gastric lesions induced by HCl/EtOH, WIRS, and indomethacin. Furthermore, it significantly decreased the volume, acidity, and total acidity of gastric juice in pylorus-ligated rats and increased the alcian blue-stained gastric mucus in HCl/EtOH-induced gastric ulcer in rats. Pretreatment with NEM abolished the gastroprotective effects of HT074, while L-NAME did not. In AGS cells, HT074 significantly reduced indomethacin-induced cell death and increased the PGE₂ levels.

Conclusions

These findings suggest that HT074 has gastroprotective effects against various ulcerogens, including HCl/EtOH, immersion stress, and NSAIDs. These effects are attributed to the inhibition of gastric secretions and preservation of the gastric mucosal barrier by increased mucus production, which is partially mediated through endogenous sulfhydryl compounds and PGE₂. Based on these findings, we propose that HT074 may be a promising therapeutic agent for gastritis and gastric ulcer.

Gastroprotective effects of methanol extract of Eremomastax speciosa leaf harvested in Southern part of Nigeria in rat

Gastric ulcer is one of the common cause of hospital consultation with an increasing prevalence worldwide and it is traditionally managed with herbal medicine in the developing countries. This study investigated the gastroprotective effects of methanol extract of Eremomastax speciosa leaf in rats. Cold maceration in 80% methanol was adopted during extract preparation while gas chromatography mass spectroscopy (GC-MS) was employed in the phytochemical analysis. The doses of 25, 50 and 100 mg/kg E. speciosa were used on ethanol-and indomethacin-induced gastric ulcer models in rats. The shay rat method was used to determine the effects of ESE on gastric acidity while the anticholinergic and antihistaminic activities were investigated on isolated rabbit jejunum ex vivo. The GC-MS analysis identified six bioactive compounds. Both ESE and cimetidine significantly (p < 0.05) reduced the severity of indomethacin- and ethanol-induced gastric injuries and gastric acid contents in Shay rats. The extract elicited concentration-dependent relaxation of isolated rabbit jejunum and reduced the contraction induced by both acetylcholine and histamine in the same tissue. The findings showed that ESE protected the rats against chemical-induced gastric ulcer through anticholinergic and antihistaminic mechanisms.

Cytoprotective, antioxidant and anti-inflammatory mechanism related to antiulcer activity of Cissampelos sympodialis Eichl. in animal models

ETHNOPHARMACOLOGICAL RELEVANCE

The leaves and roots of Cissampelos sympodialis (Menispermaceae) are used by indian tribes and in folk medicine to treat genitourinary infections, inflammation, asthma and gastrointestinal disorders.

MATERIAL AND METHODS

The standardized ethanolic extract (Cs-EtOHE) and alkaloids total fraction (Cs-TAF) obtained from aerial parts of C. sympodialis were evaluated in several models of acute gastric ulcers. The antisecretory and/or neutralizing mechanisms of the gastric acid secretion, cytoprotective, antioxidant and immunoregulatory mechanisms were also evaluated.

RESULTS

Cs-EtOHE and Cs-TAF presented a reduction in gastric mucosa lesions against ethanol, NSAIDs, hypothermic restraint-stress and gastric juice containment induced ulcer models. This activity is related to alkaloids present in the extract, and involves the participation of sulfhydryl compounds, nitric oxide, K_ATP channels, prostaglandins, decreased levels of IL-1β and TNF-α and increased levels of GSH and IL-10.

CONCLUSION

The data indicate gastroprotective activity, due to the participation of the cytoprotective, antioxidant and immunoregulatory mechanisms.

Gastroprotective and anti-inflammatory activities integrated to chemical composition of Myracrodruon urundeuva Allemão - A conservationist proposal for the species

ETHNOPHARMACOLOGICAL RELEVANCE

Myracrodruon urundeuva Allemão (Aroeira-do-Sertão), Anacardiaceae, is one of the most used plants in folk medicine in Northeastern Brazil as an anti-inflammatory, healing and antiulcer. This species is threatened with extinction due to anthropogenic exploitation. The importance of this study is to demonstrate the feasibility of a conservationist model of replacement of the M. urundeuva adult tree (inner bark) for its under developing plants (shoots) in order to ensure the preservation of this species, but also to ensure sufficient raw material for pharmaceutical purposes.

AIM OF THE STUDY

To characterize chemically and assess the gastroprotective and anti-inflammatory activities of the fluid extracts from M. urundeuva innebark (adult plant) as well as stem and leaves of shoots (young plant).

MATERIALS AND METHODS

The fluid extracts were prepared by maceration-percolation with hydroalcoholic solution according to the methodology described in the Brazilian Pharmacopoeia. These extracts were cleaned-up through solid phase extraction (SPE) and chemically characterized by ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-ESI-QTOF MS/MS). Gastroprotective and anti-inflammatory activities of the extracts (700 or 1000 mg/kg) were assessed on ethanol-induced gastric lesions and Croton oil-induced ear edema in rats, respectively. The extracts were evaluated for cytotoxicity in vitro.

RESULTS

The UPLC-ESI-QTOF-MS/MS analysis evidenced the presence of chalcones, flavonoids and tannins. Gastroprotective and anti-inflammatory activities achieved with fluid extracts from the stems and leaves was similar to inner bark. The fluid extracts were not toxic.

CONCLUSION

It is possible to replace the inner bark of the adult tree for the stems and leaves from the shoots as raw material to be used in the preparation of its the phytotherapeutics. Therefore, this finding may help in the implementation of public policies that ensure the conservation of the species along with its sustainable use for pharmaceutical purposes.

Gastroprotective effect of ethanol extracts of cladodes and roots of Pilosocereus gounellei (A. Weber ex K. Schum.) Bly. Ex Rowl (Cactaceae) on experimental ulcer models

ETHNOPHARMACOLOGICAL RELEVANCE

Pilosocereus gounellei Cactaceae), popularly known as "xique xique", is a species native from Caatinga region of Northeast Brazil, which is used by traditional communities in folk medicine for a variety of health problems, especially inflammatory processes and gastritis.

AIM OF THE STUDY

The present study investigates the possible gastric antiulceractivity of ethanol extracts obtained from the cladodes and roots of Pilosocereus gounellei (EECPG and EERPG, respectively) and mechanisms of action underlying this effect.

MATERIALS AND METHODS

Mice were used for the evaluation of the acute toxicity, and mice and rats to study the gastroprotective activity. The gastroprotective action of EECPG and EERPG was analyzed in the absolute ethanol in mice, ischemia-reperfusion and cold restraint stress in rats. In the investigation of the gastroprotective mechanisms of EECPG and EERPG, the participation of the NO and prostaglandins, the levels of the non-protein sulfhydril groups (NP-SH) and the catalase activity using the ethanol-induced gastric mucosa lesion model and the quantification of the gastric mucus and the antisecretory activity through pylorus ligature model in rats were analyzed.

RESULTS

The animals did not present any signs of acute toxicity for the EECPG and EERPG, and it was not possible to calculate the DL50. EECPG and EERPG (200 and 400 mg/kg) exhibited a significant gastroprotective effect in absolute ethanol, ischemia-reperfusion-induced and cold restraint stress gastric lesion models. Gastroprotection of EECPG and EERPG (200 mg/kg) was significantly decreased in pre-treated mice with L-NAME. Our studies revealed that EECPG and EERPG (200 mg/kg) prevented the decrease of the non-protein sulfhydril groups (NPSH) and increased the catalase levels in ethanol-treated animals. However, the gastric secretion parameters (volume, [H+], pH) did not show any alteration.

CONCLUSIONS

Our results indicate that the ethanolic extract from the cladodes and roots of Pilosocereus gounellei exhibits a significant gastroprotection, because it inhibits the formation of gastric lesions using different models. The participation of the nitric oxide, prostaglandins, the non-protein sulfhydril groups (NP-SH), catalase seem to be involved in the gastroprotection activity of the EECPG and EERPG. Nevertheless, this activity does not seem to be related to antisecretory mechanisms.

Endogenous Antioxidant and LOX-Mediated Systems Contribute to the Hepatoprotective Activity of Aqueous Partition of Methanol Extract of Muntingia calabura L. Leaves against Paracetamol Intoxication

Methanol extract of Muntingia calabura L. (family Muntingiaceae) leaf has been reported to exert various pharmacological activities including hepatoprotection. The present study was carried out to identify the most effective hepatoprotective partition derived from the extract and to determine the mechanisms of action involved. The extract was partitioned using solvents with different polarity to yield petroleum ether (PEMC), ethyl acetate (EAMC), and aqueous (AQMC) extracts. Each extract, at 250 mg/kg, was subjected to the paracetamol (PCM)-induced hepatotoxic assay and several parameters such as liver weight, liver/body weight ratio, serum liver enzymes' level, and histopathological examinations were determined. Each partition was also tested for their antioxidant and anti-inflammatory potentials. The most effective extract (AQMC) was prepared in additional dose of 50 and 500 mg/kg, and then subjected to the same liver toxicity test in addition to the endogenous antioxidant enzymes assay. Moreover, AQMC was also subjected to the phytochemical screening and HPLC analysis. Overall, from the results obtained: AQMC exerted significant (p < 0.05): (i) antioxidant activity when assessed using the DPPH, SOD and ORAC assays with high TPC detected; (ii) anti-inflammatory activity via LOX, but not XO pathway; (iii) hepatoprotective activity indicated by its ability to reverse the effect of PCM on the liver weight and liver/body weight ratio, the level of serum liver enzymes (ALT, AST, and ALP), and activity of several endogenous antioxidant enzymes (SOD and CAT). Phytochemicals analyses demonstrated the presence of several flavonoid-based bioactive compounds such as gallic acid and quercetin, which were reported to possess hepatoprotective activity. In conclusion, AQMC exerts hepatoprotective activity against the PCM-induced toxicity possibly by having a remarkable antioxidant potential and ability to activate the endogenous antioxidant system possibly via the synergistic action of its phytoconstituents.

Tohid SF, Zakaria ZA. Anticarcinogenic activity of Muntingia calabura leaves methanol extract against the azoxymethane-induced colon cancer in rats involved modulation of the colonic antioxidant system partly by flavonoids

CONTEXT

Leaves of Muntingia calabura (Elaeocarpaceae) are widely used in traditional medical practice; scientific findings show various pharmacological activities. However, its anticancer effect has not been investigated thoroughly yet.

OBJECTIVE

The objective of this study is to study the chemoprevention effects of MEMC_L against azoxymethane (AOM)-induced colon cancer and to examine the involvement of endogenous antioxidants Materials and methods: Male Sprague-Dawley rats, divided into five groups (n = 7), were injected intraperitoneally once weekly for 2 weeks with 15 mg/kg AOM, except for the normal group (received saline). The animals were then administered orally for 8 weeks with 8% Tween-80 (vehicle; normal group), 8% Tween-80 (vehicle; cancer group) or, 50, 250 or 500 mg/kg MEMC. After treatments, colon samples were collected from each rat for the histopathological analysis, quantification of aberrant crypt foci formed and determination of colon antioxidant levels. MEMC was also subjected to HPLC analysis.

RESULTS

The extract exerted significant (p < 0.05): (i) anti-carcinogenesis activity, indicated by a decrease in the total aberrant crypt formation; (ii) antioxidant activity by increasing the colon tissue antioxidant markers [i.e., superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH)] and reducing the oxidant marker (i.e., malonaldehyde (MDA) levels in comparison with the cancer group. HPLC analysis demonstrated the presence of rutin.

DISCUSSION AND CONCLUSIONS

Muntingia calabura leaves exert anticancer effect against AOM-induced colon cancer possibly via the action of flavonoids on the colon tissue antioxidant activity.

Synergistic gastroprotective activity of methanolic extract of a mixture of Melastoma malabathricum and Muntingia calabura leaves in rats

BACKGROUND

Melastoma malabathricum L. (family Melastomaceae; MM) and Muntingia calabura L. (family Elaeocarpaceae; MC) have been separately reported to possess gastroprotective activity. In an attempt to develop a pharmaceutical product with antiulcer potential, the synergistic gastroprotective activity of methanolic extract of a mixture of MM and MC (MMMC) at various ratios was evaluated in rat models.

METHODS

Rats were pre-treated orally with 2% Tween 80 (vehicle), 100 mg/kg ranitidine (reference drug) or MMMC (ratios of 1:1, 1:3 and 3:1 (v/v); doses of 15, 150 or 300 mg/kg) and then subjected to the ethanol-induced gastric ulcer or pyloric ligation assays. Stomach of rats from the former assay was collected and subjected to the macroscopic and microscopic observations, and enzymatic and non-enzymatic antioxidant studies while the gastric juice content and tissue from the latter assay were subjected to the antisecretory activity study. The UHPLC analysis of MMMC was also performed.

RESULT

MMMC, in the ratio 1:1, demonstrated the most effective (P < 0.001) gastroprotective activity indicated by the highest reduction in ethanol-induced ulcer area formation. These macroscopic findings were supported by the microscopic observations. Except for pH and total acidity, MMMC also significantly (P < 0.001) reduced the volume of gastric content but increased the gastric wall mucus content in the pyloric-ligation test. MMMC also demonstrated remarkable antioxidant activity indicated by the highest total phenolic content (TPC) value and oxygen radical absorbance capacity (ORAC) activity with the recorded IC₅₀ value of approximately 53 μg/mL for the 2,2- diphenyl-1-picrylhydrazyl (DPPH) scavenging activity. MMMC also improved the catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), prostaglandin E2 (PGE2) and malondialdehyde (MDA) activities of the gastric tissue intoxicated by ethanol. UHPLC analysis of MMMC confirmed the presence several flavonoid-based bioactive compounds.

CONCLUSION

MMMC, at the ratio of 1:1 (v/v), exerts gastroprotective activity partly by activating its antisecretory and antioxidant activities, and via modulation of the gastric tissue endogenous antioxidant system.

Gastroprotective and gastric motility benefits of AD-lico/Healthy Gut™ Glycyrrhiza inflata extract

The aim of this study was to evaluate in vivo both the anti-Helicobacter and the gastric-relaxing effects of AD-lico/Healthy Gut™ in rat models. AD-lico/Healthy Gut™ is a specially prepared commercial formulation of Glycyrrhiza inflata extract that is under clinical development for indications of gastrointestinal disease and inflammatory bowel disease. In the current study, the oral administration of AD-lico/Healthy Gut™ significantly reduced mucosal damage from Helicobacter pylori in rats and decreased the expression of the inflammatory markers iNOS and COX-2 in the test cells. AD-lico/Healthy Gut™ also reduced mucosal damage caused by water immersion stress in rats. The accelerated gastric emptying in normal rats was also seen with AD-lico/Healthy Gut™, providing relief in gastric relaxation in the test animals. The special formulation of AD-lico/Healthy Gut™ with reduced levels of component glycyrrhizin also has benefits in minimizing the potential side effects attributed to glycyrrhizin seen with similar Glycyrrhiza extracts in terms of induction of hypokalemia and muscle weakness. The preparation has a relatively high phenolic compound content relative to other methods of preparation and is indicative of lower glycyrrhizin levels. These results suggest that AD-lico/Healthy Gut™ may provide the necessary relief from a number of stomach discomfort issues faced by a large population of people.

Semipurified Ethyl Acetate Partition of Methanolic Extract of Melastoma malabathricum Leaves Exerts Gastroprotective Activity Partly via Its Antioxidant-Antisecretory-Anti-Inflammatory Action and Synergistic Action of Several Flavonoid-Based Compounds

Recent study has demonstrated the gastroprotective activity of crude methanolic extract of M. malabathricum leaves. The present study evaluated the gastroprotective potential of semipurified extracts (partitions): petroleum ether, ethyl acetate (EAMM), and aqueous obtained from the methanolic extract followed by the elucidation of the gastroprotective mechanisms of the most effective partition. Using the ethanol-induced gastric ulcer assay, all partitions exerted significant gastroprotection, with EAMM being the most effective partition. EAMM significantly (i) reduced the volume and acidity (free and total) while increasing the pH of gastric juice and enhanced the gastric wall mucus secretion when assessed using the pylorus ligation assay, (ii) increased the enzymatic and nonenzymatic antioxidant activity of the stomach tissue, (iii) lost its gastroprotective activity following pretreatment with N-omega-nitro-L-arginine methyl ester (L-NAME; NO blocker) or carbenoxolone (CBXN; NP-SH blocker), (iv) exerted antioxidant activity against various in vitro oxidation assays, and (v) showed moderate in vitro anti-inflammatory activity via the LOX-modulated pathway. In conclusion, EAMM exerts a remarkable NO/NP-SH-dependent gastroprotective effect that is attributed to its antisecretory and antioxidant activities, ability to stimulate the gastric mucus production and endogenous antioxidant system, and synergistic action of several gastroprotective-induced flavonoids.

Hepatoprotective action of various partitions of methanol extract of Bauhinia purpurea leaves against paracetamol-induced liver toxicity: involvement of the antioxidant mechanisms

Background

Methanol extract of Bauhinia purpurea L. (family Fabaceae) (MEBP) possesses high antioxidant and anti-inflammatory activities and recently reported to exert hepatoprotection against paracetamol (PCM)-induced liver injury in rats. In an attempt to identify the hepatoprotective bioactive compounds in MEBP, the extract was prepared in different partitions and subjected to the PCM-induced liver injury model in rats.

Methods

Dried MEBP was partitioned successively to obtain petroleum ether (PEBP), ethylacetate (EABP) and aqueous (AQBP) partitions, respectively. All partitions were subjected to in vitro antioxidant (i.e. total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH)- and superoxide-radicals scavenging assay, and oxygen radical absorbance capacity (ORAC) assay) and anti-inflammatory (i.e. lipooxygenase (LOX) and xanthine oxidase (XO) assay) analysis. The partitions, prepared in the dose range of 50, 250 and 500 mg/kg, together with a vehicle (10 % DMSO) and standard drug (200 mg/kg silymarin) were administered orally for 7 consecutive days prior to subjection to the 3 mg/kg PCM-induced liver injury model in rats. Following the hepatic injury induction, blood samples and liver were collected for the respective biochemical parameter and histopathological studies. Body weight changes and liver weight were also recorded. The partitions were also subjected to the phytochemical screening and HPLC analysis.

Results

Of all partitions, EABP possessed high TPC value and demonstrated remarkable antioxidant activity when assessed using the DPPH- and superoxide-radical scavenging assay, as well as ORAC assay, which was followed by AQBP and PEBP. All partitions also showed low anti-inflammatory activity via the LOX and XO pathways. In the hepatoprotective study, the effectiveness of the partitions is in the order of EABP>AQBP>PEBP, which is supported by the microscopic analysis and histopathological scoring. In the biochemical analysis, EABP also exerted the most effective effect by reducing the serum level of alanine transaminase (ALT) and aspartate transaminase (AST) at all doses tested in comparison to the other partitions. Phytochemical screening and HPLC analysis suggested the presence of: flavonoids, condensed tannins and triterpenes in EABP; flavonoids, condensed tannins and saponins in PEBP and; only saponins in AQBP.

Conclusion

EABP demonstrates the most effective hepatoprotection against PCM-induced liver injury in rats. This observation could be attributed to its remarkable antioxidant activity and the presence of flavonoids that might probably act synergistically with other biocompounds to cause the hepatoprotection.

Acute Toxicity and Gastroprotection Studies of a New Schiff Base Derived Manganese (II) Complex against HCl/Ethanol-Induced Gastric Ulcerations in Rats

Manganese is a crucial element for health. In this study, the gastroprotective efficacy of Mn (II) complex (MDLA) against acidified ethanol (HCl/Ethanol)-induced gastric ulceration in rats was evaluated. The animals were distributed into 5 groups. Groups 1 and 2 received carboxymethylcellulose (CMC), group 3 was pretreated with omeprazole, and groups 4 and 5 were given 10 and 20 mg/kg of MDLA, respectively. After one hour, CMC and HCl/Ethanol were given to groups 2–5 whilst the animals in group 1 were ingested with CMC. After sacrifice, gastric lesions were evaluated by wall mucus, gross appearance, histology, antioxidant enzymes and immunohistochemistry. Group 2 displayed severe gastric damage with a significant reduction in wall mucus. Conversely, gastric lesions were reduced in groups 3–5 by 85.72%, 56.51% and 65.93%, respectively. The rats in groups 3–5 showed up-regulation of heat shock protein 70 (Hsp70) with down-regulation of Bcl-2-associated protein x (Bax). Pretreatment with omeprazole or MDLA led to an increase in the uptake of Periodic Acid Schiff (PAS) stain in the glandular part of the gastric tissue, raised levels of prostaglandin E2 (PGE₂) and superoxide dismutase (SOD), and a reduction in malondialdehyde (MDA) concentrations. These results suggested the gastroprotective action of Mn (II) complex.

Mechanism(s) of action underlying the gastroprotective effect of ethyl acetate fraction obtained from the crude methanolic leaves extract of Muntingia calabura

Background

Muntingia calabura L. (family Muntingiaceae), commonly known as Jamaican cherry or kerukup siam in Malaysia, is used traditionally to treat various ailments. The aim of this study is to elucidate the possible underlying gastroprotective mechanisms of ethyl acetate fraction (EAF) of Muntingia calabura methanolic leaves extract (MEMC).

Methods

MEMC and its fractions were subjected to HPLC analysis to identify and quantify the presence of its phyto-constituents. The mechanism of gastroptotection of EAF was further investigated using pylorus ligation-induced gastric lesion rat model (100, 250, and 500 mg/kg). Macroscopic analysis of the stomach, evaluation of gastric content parameters such as volume, pH, free and total acidity, protein estimation, and quantification of mucus were carried out. The participation of nitric oxide (NO) and sulfhydryl (SH) compounds was evaluated and the superoxide dismutase (SOD), gluthathione (GSH), catalase (CAT), malondialdehyde (MDA), prostaglandin E₂ (PGE₂) and NO level in the ethanol induced stomach tissue homogenate was determined.

Results

HPLC analysis confirmed the presence of quercetin and gallic acid in EAF. In pylorus-ligation model, EAF significantly (p <0.001) prevent gastric lesion formation. Volume of gastric content and total protein content reduced significantly (p < 0.01 and p < 0.05, respectively), while free and total acidity reduced in the doses of 250 and 500 mg/kg (p <0.001 and p <0.05, respectively). EAF also augmented the mucus content significantly (p < 0.001). Pre-treatment with N-nitro-L-arginine methyl ester (L-NAME) or N-ethylmaleimide (NEM) reversed the gastroprotective activity of EAF. EAF treatment markedly ameliorated the SOD, GSH and CAT activity and PGE₂ and NO level while attenuating MDA level, relative to the vehicle group.

Conclusions

In conclusion, the underlying gastroprotective mechanisms of EAF could be associated with the antisecretory, participation of mucus, antiperoxidative, improvement of antioxidant status, modulation of NO and SH compounds, stimulation of PGE₂ as well as presence of quercetin and gallic acid.

Protective Effects of Manassantin A against Ethanol-Induced Gastric Injury in Rats

Manassantin A, a neolignan isolated from Saururus chinensis, is a major phytochemical compound that has various biological activities, including anti-inflammatory, neuroleptic, and human acyl-CoA : cholesterol acyltransferase (ACAT) inhibitory activities. In this study, we investigated the protective effects of manassantin A against ethanol-induced acute gastric injury in rats. Gastric injury was induced by intragastric administration of 5 mL/kg body weight of absolute ethanol to each rat. The positive control group and the manassantin A group were given oral doses of omeprazole (20 mg/kg) or manassantin A (15 mg/kg), respectively, 1 h prior to the administration of absolute ethanol. Our examinations revealed that manassantin A pretreatment reduced ethanol-induced hemorrhage, hyperemia, and epithelial cell loss in the gastric mucosa. Manassantin A pretreatment also attenuated the increased lipid peroxidation associated with ethanol-induced acute gastric lesions, increased the mucosal glutathione (GSH) content, and enhanced the activities of antioxidant enzymes. The levels of pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1β were clearly decreased in the manassantin A-pretreated group. In addition, manassantin A pretreatment enhanced the levels of cyclooxygenase (COX)-1, COX-2, and prostaglandin E2 (PGE2) and reduced the inducible nitric oxide synthase (iNOS) overproduction and nuclear factor kappa B (NF-κB) phosphorylation. Collectively, these results indicate that manassantin A protects the gastric mucosa from ethanol-induced acute gastric injury, and suggest that these protective effects might be associated with COX/PGE2 stimulation, inhibition of iNOS production and NF-κB activation, and improvements in the antioxidant and anti-inflammatory status.

Gastroprotective activity of chloroform extract of Muntingia calabura and Melastoma malabathricum leaves

CONTEXT

Muntingia calabura L. (family Muntingiaceae) and Melastoma malabathricum L. (family Melastomaceae) are traditionally used to treat gastric ulcer.

OBJECTIVE

The present study determines the mechanisms of gastroprotective activity of the chloroform extract of leaves obtained from both the plants using several in vitro and in vivo assays.

MATERIALS AND METHODS

Phytochemical screening, HPLC analysis, and antioxidant activity of the respective extract were carried out. Gastroprotective activity was determined using ethanol-induced gastric ulcer assay while the mechanisms of gastroprotection were determined using the pyloric ligation assay. The test solutions [8% Tween-80 (vehicle), 20 mg/kg omeprazole, and different doses of extracts (50, 250, or 500 mg/kg] were administered orally once daily for 7 consecutive days before the animals were subjected to ethanol induced gastric ulcers.

RESULTS

The chloroform-extracted M. calabura (CEMC) contains tannins, polyphenolics, triterpenes, and steroids while the chloroform-extracted M. malabathricum (CEMM) contains only triterpenes and steroids. CEMC, but not CEMM, exerted remarkably strong antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH)- (86% versus 16%) and superoxide- (73% versus 36%) radical scavenging assays. Both extracts demonstrated significant (p < 0.05) gastroprotection with the EC50 value recorded at 192.3 or 297.7 mg/kg, respectively. In the pylorus ligation assay, CEMC and CEMM significantly (p < 0.05) reduced the total and free acidity and volume; while increased the pH of gastric juice as well as the gastric wall mucus content in comparison with the vehicle-treated group.

DISCUSSION AND CONCLUSION

CEMC and CEMM exert gastroprotective effects in animals with ethanol-induced gastric ulcers via antioxidant and anti-secretory effects.

Antioxidant and anti-inflammatory activities contribute to the prophylactic effect of semi-purified fractions obtained from the crude methanol extract of Muntingia calabura leaves against gastric ulceration in rats

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional medicine, the leaves, flowers, barks and roots of Muntingia calabura L. (Muntingiaceae) have been employed as a treatment for various ailments including dyspepsia and to relieve pain caused by gastritis and peptic ulcer disease. The methanolic extract of Muntingia calabura leaves (MEMC) has been proven in the previous study to possess significant antiulcer activity. In this study, we attempted to determine the prophylactic effect of the fractions obtained from MEMC against ethanol-induced gastric lesion in rats and the involvement of antioxidants and anti-inflammatory mediators.

MATERIALS AND METHODS

The MEMC was fractionated with petroleum ether (PEF), ethyl acetate (EAF) and distilled water (AQF). These fractions were investigated for possible antiulcer property using ethanol-induced gastric ulcer rat model. The rats were administered orally once daily with 8% Tween 80 (control), 100mg/kg ranitidine, or the fractions, in the doses of 100, 250, and 500 mg/kg, for 7 days, followed by ulcer induction using absolute ethanol. The rats were euthanized; macroscopic and histological observations of the stomach were done. The ulcer area (UA) was determined and the percentage protection afforded by the fractions was calculated. The fractions were subjected to antioxidant studies including the superoxide and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, oxygen radical absorbance capacity (ORAC) and total phenolic content (TPC) assay. Involvement of nitric oxide (NO) and inflammatory mediators such as lipoxygenase (LOX) and xanthine oxidase (XO) were evaluated. Phytochemical screening and HPLC analysis of the fractions were also conducted.

RESULTS

Pre-treatment of PEF and EAF significantly (p<0.001) attenuated the gastric lesions as compared to the control group in a dose-dependent manner. On the other hand, 100 and 250 mg/kg of AQF significantly (p<0.001) prevented the ulcer formation but at the highest dose (500 mg/kg), AQF failed to significantly reduce the ulcer formation, showing a dose-independent antiulcerative effect of AQF. The histological evaluation supported the observed gastroprotective activity of PEF, EAF and AQF. All the fractions showed high superoxide and DPPH scavenging activity, meanwhile the EAF showed highest TPC followed by PEF and AQF. These fractions also significantly (p<0.05) inhibited the NO while maintaining the viability of the cells. EAF exhibited high inhibition towards both the LOX and XO enzymes, meanwhile PEF and AQF exerted high LOX inhibition but low XO inhibition. Phytochemical screening and HPLC profiling suggested the presence of flavonoid- and tannin based compounds in PEF and EAF.

CONCLUSION

It can be concluded that the prophylactic effect of the fractions on gastric ulceration in rats is associated with its high antioxidant activity and its ability to effectively inhibit the inflammation mediators. Presence of several flavonoids and gallic acid explains the effectiveness of the fractions in affording protection against gastric damages.

Antiulcer activities of the hydroethanolic extract of Sedum dendroideum Moc et Sessé ex DC. (balsam)

ETHNOPHARMACOLOGICAL RELEVANCE

The leaves of Sedum dendroideum, commonly known as balsam, have long been employed for the treatment of gastric ulcers. The aim of study was to evaluate the antiulcer activity and toxicological properties of Sedum dendroideum using induced gastric ulcer models in Wistar rats.

MATERIALS AND METHODS

The hydroethanolic extract of Sedum dendroideum (ESD) was analyzed using an acute ulcer model using ethanol and indomethacin and a chronic ulcer model using acetic acid. The toxicity was evaluated with acute and subacute toxicity tests. The gastric secretion was assessed by the performance of pyloric ligation and the gastric volume, pH, and hydrogen ion concentration. The mechanism of the gastroprotective activity of ESD through the involvement of nitric oxide and sulfhydryl compounds was assessed. Moreover, a phytochemical screening and antioxidant assays were performed.

RESULTS

No signs of toxicity were observed. In the ethanol-induced ulceration model, ESD doses of 25, 50, and 100mg/kg significantly reduced the gastric lesions by 66.03%, 71.11%, and 70.82%, respectively. In the indomethacin-induced ulceration model, ESD doses of 25, 50, and 100mg/kg significantly reduced the gastric lesions by 89.88%, 94.36%, and 90.64%, respectively. Treatment with ESD at 50mg/kg and cimetidine at 200mg/kg significantly reduced acetic acid-induced ulcerations and resulted in 92.99% and 77.16% cure, respectively. ESD doses of 25, 50, and 100mg/kg inhibited oxidation by 79.7%, 82.4%, and 82.3%, respectively. The antiulcer activity of ESD may involve sulfhydryl compounds, considering that this activity was inhibited in the animals treated with sulfhydryl compound blockers. Furthermore, ESD increased mucus secretion and reduced gastric acidity and volume.

CONCLUSIONS

The leaf extract of Sedum dendroideum exhibited gastroprotective activity, potentially due to sulfhydryl compounds and antioxidant activity. Therefore, other studies are warranted to elucidate the antiulcer properties of these compounds.

Mechanisms involved in the gastroprotective activity of Celtis iguanaea (Jacq.) Sargent on gastric lesions in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Celtis iguanaea (Canabaceae) is popularly known as esporão-de-galo, stands out among the medicinal plants used for treatment of gastric ulcers. In Brazil, the leaves they are used traditionally in infusion forms as an analgesic, antiasthmatic, digestive and diuretic.

AIM OF THE STUDY

The present study was aimed to investigate the antiulcer mechanisms of hexane extract Celtis iguanaea leaves (HE) in several induced-gastric ulcer and characterize its chemical composition.

MATERIALS AND METHODS

The HE was obtained by exhaustive extraction in Soxhlet apparatus. The chemical characterization of HE was performed by Electrospray Fourier transform ion cyclotron mass spectrometry (ESI FT-ICR MS) analysis. Mice were used for the evaluation of the gastroprotective activity. HE was analyzed in the HCl/ethanol, hypothermic restraint stress ulcer and acetic acid. In the investigation of the gastroprotective mechanisms of HE, were performed the amount of adhered gastric mucus, participation of the α2-adrenoceptor, nitric oxide (NO) and prostaglandins (PGs) using the HCl/ethanol-induced gastric mucosa lesion model.

RESULTS

ESI FT-ICR MS analysis of HE suggest the presence of compounds as lipids, sterol lipids, steroids glycosides and polyphenol glycosides. The oral administration of HE at doses of 100 mg/kg or 200 mg/kg was able to protect the gastric mucosa against HCl/ethanol (10 mL/kg p.o.), and HE at dose of 100mg/kg protected against hypothermic-restraint stress and acetic -induced gastric lesions. The pretreatment with Yoimbine (2mg/kg, s.c.), an antagonist α2-adrenergic, L-NAME (20mg/kg, s.c.), an inhibitor of nitric oxide synthesis or indomethacin (10mg/kg, s.c.), an inhibitor of prostaglandin production, reversed the gastroprotective activity of HE (100mg/kg, p.o.).

CONCLUSIONS

Our results suggest that the Celtis iguanaea HE exhibits gastroprotective activity in different gastric ulcer models. The mechanism of gastroprotective effect of Celtis iguanaea HE suggests the participation of mucus as well as the involvement of α2-adrenergic receptors, NO and prostaglandins. The hydroxyl-linolenic acid, linoleic acids and conjugated oxo-linoleic acids are among the phytoconstituents that were identified in the Celtis iguanaea HE.