Gastroprotective effect of cyanidin 3-glucoside on ethanol-induced gastric lesions in rats

Gastroprotective potential of red onion (Allium cepa L.) peel in ethanol-induced gastric injury in rats: Involvement of Nrf2/HO-1 and HMGB-1/NF-κB trajectories

ETHNOPHARMACOLOGICAL RELEVANCE

The utilization of plants with therapeutic properties in traditional medicine has a longstanding practice. Among them, the well-known Allium cepa L. commonly known as onion has been valued for its anti-inflammatory and antioxidant potential in the treatment of various ailments, including gastric ulcers.

AIM OF THE STUDY

This study investigated the gastroprotective potential of red onion peel extract and its fractions in a rat model of ethanol-induced gastric ulcer. Moreover, their phytochemical profiles were compared to identify the active metabolites.

MATERIALS AND METHODS

Mass spectrometry-based metabolomics and chemometrics were performed for phytochemical analysis. Ethanol-induced gastric ulcer model was used to assess the gastroprotective activity. Nine groups of rats were allocated as follows: Group 1 was the normal control; Group 2 rats were used as a positive control/model and received 1 mL of absolute ethanol; and Group 3 rats were treated with famotidine at a dose of 20 mg/kg orally. Group 4 and 5 rats were treated with total acidified ethanolic extract (T1, T2). Group 6 and 7 rats were treated with anthocyanins-rich fractions (P1, P2). Groups 8 and 9 were the flavonoids-rich fraction (S1, S2) treatment. Prior to scarification, the ulcer index in mm was obtained from gastric tissues photographed beside a ruler with further analysis using ImageJ software.

RESULTS

Seventy key major and discriminatory metabolites were identified including flavonoids, anthocyanins, phenolic acids, and miscellaneous compounds. The examined extract and its fractions significantly reduced the ulcer index and inflammatory cytokines via downregulating HMGB-1/NF-κB. Also, they augmented the expression of Nrf2/HO-1 and reduced NOX1/4 mRNA expression. Moreover, there was a significant reduction in the oxidative stress and apoptotic biomarkers as well as a noticeable enhancement in histopathological changes of the stomach tissues.

CONCLUSION

Red onion peels have a promising dose dependent gastroprotective potential in alcohol-induced ulcers via modulating Nrf2/HO-1 and HMGB-1/NF-κB trajectories. This highlights the potential of red onion peels in treating gastric ulcers.

Toxicity and Antiulcer Properties of Ipomoea wightii (Wall.) Choisy Leaves: An In Vivo Approach Using Wistar Albino Rats

Humans have been using herbs to prevent and cure various ailments since antiquity, and Ipomoea wightii is a significant medicinal plant known for its wide ethnobotanical uses. Although the plant is known to treat ulcers, there is no significant scientific validation. The present study aimed to assess the acute toxicity, subacute toxicity, and antiulcer properties of the leaf methanol extract of I. wightii (IWL). In the subacute study, the extracts were given orally at 100, 200, and 400 mg/kg doses for 28 days, and we analyzed the biochemical and histological parameters to evaluate the toxicity of IWL. Two different models were assessed to explore antiulcer properties, such as indomethacin- and ethanol-induced ulcer model. Ulcer areas and ulceration percentage histopathology of the stomach were used to study the efficacy of extracts. The acute toxicity study showed that IWL was safe to the maximum dose of 2000 mg/kg body weight. In a subacute toxicity study, the oral administration of IWL did not produce any mortality in the tested animals. The analysis of haematological, liver biochemical, kidney profile, lipid profile, and in vivo antioxidant parameters depicted that all the values were within the control limits after the experimental period and were considered nontoxic to animals. Additionally, the antiulcer study demonstrated a positive response of IWL in a dose-related manner (indomethacin- and ethanol-induced models). Macroscopic analysis showed that pretreatment with I. wightii leaf methanol extract significantly reduced the gastric lesion and decreased the ulceration area (14.52 mm²), demonstrating superior results to the positive control group (27.71 mm²). The histopathological analysis revealed that pretreatment with a high dose of 400 mg/kg of I. wightii leaf methanol extract and positive control group (omeprazole) markedly protected pathological effects, and the gastric mucosa appeared normal. In conclusion, I. wightii has solid nontoxic potential as a promising native herb for an integral therapy for the treatment of ulcers.

Physiological Effects and Human Health Benefits of Hibiscus sabdariffa: A Review of Clinical Trials

Hibiscus sabdariffa Linn. Malvaceae (HS) is characterized by its edible calyxes. The HS calyxes are widely used for cosmetic, food, and medicinal applications. According to ethnobotanical evidence, decoction, infusion, or maceration extracts from HS calyxes have been used in folk medicine to treat many ailments. Moreover, several in vitro and in vivo studies have demonstrated the pharmacological properties and potential human health benefits of HS consumption. On the other hand, the evaluation of the physiological effects and health benefits of HS in clinical studies is most challenging. Therefore, this narrative review summarizes and discusses the physiological effects and health benefits of HS calyxes reported in clinical trials. Preparations obtained from HS calyxes (extracts, infusions, decoction, teas, beverages, capsules, and pills) are used as non-pharmacological therapies to prevent/control diverse chronic non-communicable diseases. The most-reported HS health benefits are its antihypertensive, antidyslipidemic, hypoglycemic, body fat mass reduction, nephroprotective, antianemic, antioxidant, anti-inflammatory, and anti-xerostomic activities; these effects are associated with the phytochemicals found in HS. Moreover, no adverse effects were reported during the clinical trials. However, clinical studies exhibited some limitations; thus, further studies are required to validate the clinical efficacy of HS in large-scale studies with higher doses and a good experimental design

Agarwood Alcohol Extract Protects against Gastric Ulcer by Inhibiting Oxidation and Inflammation

Background

Agarwood has been used for centuries, especially for treatment of gastrointestinal diseases. Earlier studies of our laboratory suggested that agarwood alcohol extracts (AAEs) provided gastric mucosal protection. This study aims to investigate the ameliorative effect of AAEs on ethanol-induced gastric ulcers and its mechanism.

Methods

Mice were given agarwood induced by the whole-tree agarwood-inducing technique alcohol extract (WTAAE, 0.71, 1.42, and 2.84 g/kg), wild agarwood induced by axe wounds alcohol extract (WAAE, 2.84 g/kg), and burning-chisel-drilling agarwood alcohol extract (FBAAE, 2.84 g/kg) orally, respectively. After 7 days' pretreatment with AAEs, the gastric ulcers were induced by absolute ethanol. The ulcer index, gastric histopathology, biochemical parameters, and inflammatory proteins were evaluated.

Results

Pharmacological results showed AAEs (1.42 and 2.84 g/kg) reduced the gastric occurrence and ulcer inhibition rates up to more than 60%. AAEs decreased the level of nitric oxide (NO) and increased glutathione (GSH) and superoxide dismutase (SOD) levels. Besides, AAEs decreased the levels of interleukin-1β (IL-1β) and interleukin-6 (IL-6), but the interleukin-10 (IL-10) was upregulated. The expressions of nuclear factor kappa B (NF-κB) and phosphorylated protein 38 (p-P38) were inhibited. The effect of WTAAE was better than that of FBAAE and similar to that of WAAE at the dose of 2.84 g/kg.

Conclusions

These results demonstrate that agarwood alleviates the occurrence and development of gastric ulcers via inhibiting oxidation and inflammation.

Effects of anthocyanin, astaxanthin, and lutein on eye functions: a randomized, double-blind, placebo-controlled study

We examined the effects of a test food containing anthocyanin, astaxanthin, and lutein on the eye function in healthy Japanese adults with eye fatigue after operating visual display terminals. Forty-four subjects were randomly but equally assigned to the active or placebo group. Two active or placebo capsules were taken once daily for 6 weeks. Accommodative function, tear film break-up time, visual acuity, the value of Schirmer's test, macular pigment optical density level, muscle hardness, and a questionnaire were evaluated before and after a 6-week intervention. Each group included 20 subjects in the efficacy analysis. The active group showed a significant improvement in the percentage of pupillary response of an average of both eyes and dominant eye pre- and post-visual display terminal operation at 6 weeks compared with the placebo group. Moreover, the active group showed a significant improvement in the scores of "A sensation of trouble in focusing the eyes" and "Difficulty in seeing objects in one's hand and nearby, or fine print" compared with the placebo group between before and after ingestion. Therefore, 6-weeks consumption of the test food inhibited a decrease in the accommodative function caused by visual display terminal operation (UMIN000036989).

Anthocyanins: Promising Natural Products with Diverse Pharmacological Activities

Anthocyanins are natural products that give color to plants. As natural plant pigments, anthocyanins also have a series of health-promoting benefits. Many researchers have proved that anthocyanins have therapeutic effects on diseases, such as circulatory, nervous, endocrine, digestive, sensory, urinary and immune systems. Additionally, a large number of studies have reported that anthocyanins have an anticancer effect through a wide range of anti-inflammatory and antioxidant effects. The anti-disease impact and mechanism of anthocyanins are diverse, so they have high research value. This review summarizes the research progress of anthocyanins on the pharmacological agents of different diseases to provide references for subsequent research.

Lactobacillus plantarum ZS62 Alleviates Alcohol-Induced Gastric Injury in Mice via an Anti-Oxidative Mechanism

Aim

Gastric mucosal injury is a typical characteristic of gastric diseases. The prevalence of gastric mucosal injury caused by alcohol has been on the rise, which has been considered a serious problem. The purpose of this study is to explore the protective effect on gastric injury of Lactobacillus plantarum ZS62 (LP-ZS62) isolated from naturally fermented yak yoghurt.

Methods

We established a gastric injury model through alcohol and evaluated the protective effect of LP-ZS62 on gastric injury in mice. The injury to the gastric mucosa, histopathological sections, related biochemical indicators, and related genes were examined to evaluate the protective effect of LP-ZS62.

Results

LP-ZS62 effectively alleviated alcohol-induced gastric injury according to visual observations of gastric tissue and pathological tissue sections. The experimental results revealed that LP-ZS62 decreased malondialdehyde (MDA) level, and elevated superoxide dismutase (SOD) and glutathione (GSH) levels in gastric tissues. Additionally, LP-ZS62 increased glutathione peroxidase (GSH-Px), prostaglandin E2 (PGE2), and somatostatin (SS) levels. LP-ZS62 also decreased inflammatory cytokines interleukin (IL)-1β, tumor necrosis factor-α (TNF-α) and IL-6 levels, and increased the anti-inflammatory cytokine IL-10 level. The quantitative polymerase chain reaction results showed that LP-ZS62 upregulated mRNA expression of nuclear factor E2-related factor 2 (Nrf2), copper/zinc superoxide dismutase (SOD1), manganese superoxide dismutase (SOD2), catalase (CAT), gamma-glutamylcysteine synthetase (GSH1), and glutathione peroxidase (GSH-Px).

Conclusion

This study confirmed that LP-ZS62 alleviated alcohol-induced gastric injury by regulating antioxidant capacity. Therefore, LP-ZS62 could be developed as a probiotic product to treat alcoholic gastric injury.

Anti-Inflammatory Effect of Artemisia argyi on Ethanol-Induced Gastric Ulcer: Analytical, In Vitro and In Vivo Studies for the Identification of Action Mechanism and Active Compounds

Artemisia argyi is widely used as traditional medicine in East Asia. However, its effects against inflammation and gastric ulcers have not been reported yet. We analyzed anti-inflammatory activity and its molecular mechanisms of A. argyi using RAW264.7 cells line, then evaluated the curative efficacy in rats with acute gastric ulcers. Nitric oxide and IL-6 production was measured using Griess reagent and an ELISA kit. Inducible nitric oxide synthase (iNOS), interleukin (IL)-6, and mucin (MUC)1, MUC5AC, and MUC6 mRNA were determined by SYBR Green or Taqman qRT-PCR methods. The phosphorylation of ERK, JNK, p38, and c-Jun protein were detected by western blotting. RW0117 inhibited LPS-induced NO and IL-6 production. The mRNA levels of iNOS and IL-6 were strongly suppressed. The phosphorylation of ERK, JNK, and c-Jun decreased by treatment with RW0117. Oral administration of RW0117 recovered the amount of mucin mRNA and protein level that was decreased due to gastric ulcers by HCl-EtOH. A. argyi exhibited strong anti-inflammatory effects and contributed to the modulation of HCl-EtOH-induced gastric ulcer in rats.

Gastroprotective effects of irsogladine maleate on ethanol/hydrochloric acid induced gastric ulcers in mice

BACKGROUND/AIMS

This study was conducted to investigate the inhibitory effect of irsogladine maleate (IM) on gastric ulcers induced by ethanol and hydrochloric acid (HCl).

METHODS

Mice were pretreated with IM for 1 hours before ulcer induction. Gastric ulcers were induced by oral administration of an ethanol/HCl mixture. To clarify the action mechanism of IM, the roles of 3'5'-cyclic adenosine monophosphate (cAMP), nitric oxide (NO), adenosine triphosphate-sensitive potassium (KATP) channels, prostaglandins and transient receptor potential cation channel subfamily V member 1 (TRPV1) were investigated, and lipid peroxidation in the stomach of IM-treated and -untreated animals was also measured.

RESULTS

IM significantly reduced the extent of ethanol/HCl mixture-induced gastric ulceration. It exhibited dose-related gastroprotection against the ethanol/ HCl-induced lesions, while pretreatment with glibenclamide but not N(ω)-nitro- L-arginine methyl ester, reversed this action. While pretreatment with the TRPV1 antagonist capsazepine failed to effectively block the gastroprotective effect of IM, the non-selective cyclooxygenase inhibitor indomethacin almost abolished it. IM also decreased the level of thiobarbituric acid reactive substances.

CONCLUSION

We concluded that IM exhibited significant gastroprotective effects in an ethanol/HCl-induced ulcer model, which appear to be mediated, at least in part, by NO, cAMP, endogenous prostaglandins, KATP channel opening, activation of TRPV1 channels, and antioxidant properties.

Anti-ulcerogenic potential of anthocyanin-loaded chitosan nanoparticles against alcohol-HCl induced gastric ulcer in rats

Chitosan is more prominent in food applications due to its versatile properties. Anthocyanins have gained much research attention due to their multifaceted role in preventing various lifestyle ailments. Encapsulated anthocyanin- loaded chitosan nanoparticles (ACNPs) were prepared by conventional ionotropic gelation method. In the present study, the gastro-protective effect of encapsulated ACNPs was evaluated against absolute ethanol-hydrochloric acid (HCl-Ethanol mixture) induced gastric ulcer in male Wistar rats. The histopathology and microscopic scoring of ulcer data of stomach tissue sections revealed that oral administration of encapsulated ACNPs group can alleviate inflammation of induced-gastric ulcer. Further, the expression of anti-inflammatory cytokines (Interleukin 4, IL-4) and suppression of pro-inflammatory cytokines (Interferon gamma, IFN-γ) confirm the cytoprotective effect of encapsulated ACNPs against HCl-Ethanol induced necrotic damage to mucosal membrane. The results of the present study indicate that the gastro protective action of encapsulated ACNPs ascribable to at least in parts to its anti-inflammatory property.

New γ-pyrone glycoside from Pachira glabra and assessment of its gastroprotective activity using an alcohol-induced gastric ulcer model in rats

Pachira glabra is a medium sized tree that is famous for its delicious edible seeds and leaves. Phytochemical investigation of Pachira glabra leaf alcohol extract led to the isolation of a new γ-pyrone glycoside, 7-hydroxy maltol-3-O-β-d-glucoside (HMGlu). In vivo assessment of the gastro-protective activity of HMGlu demonstrated superior gastro-protection at a dose of 100 mg kg-1, close to the value triggered by the standard reference omeprazole drug (evidenced by morphological and histopathological examinations). This was further confirmed by immunohistochemical staining where pretreatment with HMGlu (100 mg kg-1) markedly reduced NFκB, COX-2 and BAX positively-stained cells. Thus, it can be concluded that 7-hydroxy maltol-3-O-β-d-glucoside can be a new pharmaceutically active agent with promising gastro-protective activity of natural origin.

Antiulcer Activity of Steamed Ginger Extract against Ethanol/HCl-Induced Gastric Mucosal Injury in Rats

Ginger (Zingiber officianale), the most widely consumed species, is traditionally used as a folk medicine to treat some inflammatory diseases in China and Korea. However, the functional activity of steamed ginger extract on gastric ulcers has not been previously explored. The present study aimed to investigate antiulcer activity of steamed ginger extract (GGE03) against ethanol (EtOH)/HCl-induced gastric ulcers in a rat model. GGE03 (100 mg/kg) was orally administered for 14 days to rats before oral intubation of an EtOH/HCl mixture to induce gastric damage. Pretreatment with GGE03 markedly protected the formation of microscopic pathological damage in the gastric mucosa. Further, administration of GGE03 significantly increased mucosal total nitrate/nitrite production in gastric tissues, and elevated total GSH content, catalase activity and superoxide dismutase (SOD) expression as well as decreasing lipid peroxidation and myeloperoxidase (MPO) activity. Underlying protective mechanisms were examined by assessing inflammation-related genes, including nuclear factor-κB (NF-κB), prostaglandin E2 (PGE2), and pro-inflammatory cytokines levels. GGE03 administration significantly reduced the expression of NF-κB and pro-inflammatory cytokines. Our findings suggest that GGE03 possesses antiulcer activity by attenuating oxidative stress and inflammatory responses.

Natural deep eutectic solvent (NADES)-based blueberry extracts protect against ethanol-induced gastric ulcer in rats

Blueberry is a polyphenol-rich fruit bearing great bioactive potential. Natural deep eutectic solvents (NADES) emerged as putatively biocompatible solvents that could substitute for toxic organic solvents in the extraction of fruit phenolic compounds for developing nutraceuticals or functional foods. Therefore, the aim of this study was to investigate the gastroprotective effects and the biocompatibility of a blueberry crude extract (CE) obtained using NADES and of the extract fractions (anthocyanin-rich fraction - ARF; non-anthocyanin phenolic fraction - NAPF) in a model of ethanol-induced gastric ulcer in rats. CE was the NADES-containing, ready-to-use extract that was obtained using choline chloride:glycerol:citric acid NADES (0.5:2:0.5 M ratio). ARF and NAPF were the NADES-free fractions obtained by solid phase purification of CE and were investigated to identify the bioactive fraction responsible for the effects of CE. Animals were treated for 14 days with water, NADES vehicle, CE, ARF, NAPF or lansoprazole (intragastric) and then received ethanol to induce gastric ulcer. CE decreased ulcer index and preserved the integrity of gastric mucosa. The pretreatment with CE or ARF reduced glutathione depletion and the inflammatory response. All treatments, including NADES vehicle reduced protein oxidation and nitric oxide overproduction in ethanol-treated rats. Additionally, ARF increased short-chain fatty acids in feces. These findings suggest that NADES can be used to obtain biocompatible extracts of blueberry that exhibit gastroprotective effects with no need of solvent removal. The gastroprotective effects were mainly associated to ARF but NAPF and even NADES vehicle also contributed to some protective effects.

Açaí berries (Euterpe oleracea Mart.) dried extract improves ethanol-induced ulcer in rats

OBJECTIVES

Açaí (Euterpe oleracea) is widely consumed in Brazil and known for its numerous health-beneficial properties. This study investigated the gastroprotective potential of the dried açaí berries extract (DAE).

METHODS

Dried açaí berries extract effect was evaluated against ethanol-induced gastric ulcer in rats. Its ability to regulate antioxidant defenses and reduce inflammatory parameters was evaluated in the ulcerated tissues. The scavenger capability of DAE was assessed by DPPH assay, and phytochemical composition was accessed by UHPLC.

KEY FINDINGS

The extract showed radical scavenger activity in vitro (IC₅₀  = 210 µg/ml) and gastroprotective effect in vivo, reducing the ulcerated area by 83%, 67% and 48% at doses of 30 and 100 mg/kg (p.o) and 3 mg/kg (i.p), respectively, compared with vehicle group. Besides, DAE (100 mg/kg, p.o) increased the GSH content and GST activity in ulcerated mucosa. Animals treated with DAE showed normalized levels of SOD activity, elevated CAT activity and decreased MPO activity, as well as reduced TNF-α levels, compared with vehicle group. Peonidin-3-glucoside, peonidin-3-rutinoside, cyanidin-3,5-hexoside-pentoside, cyaniding-3-glucoside, pelargonidin-3-glucoside and pelargonidin-3-rutinoside were identified in DAE.

CONCLUSIONS

Our findings suggest that DAE reduces the inflammation and maintains the oxidative balance of gastric mucosa, therefore being a promising natural resource or useful nutraceutical to protect gastric mucosa.

Lipid Nanoemulsions of Rebamipide: Formulation, Characterization, and In Vivo Evaluation of Pharmacokinetic and Pharmacodynamic Effects

Rebamipide has low oral bioavailability (10%) due to its low solubility and permeability. Lipid nanoemulsions (LNEs) were prepared in order to improve its oral bioavailability. Rebamipide-loaded lipid nanoemulsions were formulated by hot homogenization and ultrasonication method. Olive oil and egg lecithin in various concentrations as emulsifier were used in the preparation of LNEs. The lipid nanoemulsions were evaluated for various parameters. The globule size, polydispersity index (PDI), and zeta potential (ZP) of the formulations ranged from 230.3 ± 3.88 to 279.8 ± 5.76 nm, 0.204 ± 0.008 to 0.246 ± 0.029, and - 27.7 ± 2.05 to - 31.0 ± 1.87 mV, respectively. Entrapment efficiency and assay values ranged from 99.90 ± 0.006 to 99.92 ± 0.002% and 99.3 ± 0.808 to 99.6 ± 0.360, respectively. Physical stability test results revealed that the optimized LNEs were stable for 2 months at both room (25°C) and refrigerated temperature (4°C). The optimized LNE showed 4.32-fold improvement in the oral bioavailability in comparison to a marketed tablet suspension. In vivo anti ulcer activity of rebamipide LNE was studied by testing the prophylactic effect in preventing the mucosal damage in stomach region. The mucosa of stomach in animals was damaged by per oral administration of 80% alcohol. Maximum prophylactic antiulcer activity was observed by per oral delivery of rebamipide as LNE. Our results indicated that LNEs were a promising approach for the oral delivery of rebamipide for systemic effects along with local effects in protecting gastric region, which gets damaged during peptic ulcers.

Anti-ulcer effect of Gallarhois extract with anti-oxidant activity in an ICR model of ethanol/hydrochloride acid-induced gastric injury

Gallarhois (GR) is a traditional oriental herbal medicine with various pharmacological effects; however, its effect on gastric ulcer has not been previously explored. We firstly investigated the component and antioxidant activity of GR extract (EtGR) by HPLC analysis and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The results showed that EtGR consisted of gallotannin (68.7%), gallic acid (27.2%) and methyl gallate (4.1%) and that it had a high antioxidant value (IC50 value; 1.93 μg/mL). To evaluate the possible anti-gastric ulcer potential of EtGR, we investigated the effects of EtGR in the model of ethanol/hydrochloric acid (EtOH/HCl)-induced gastric ulcer. Gross and histological gastric lesions, biochemical and gene expression parameters were taken into consideration. The results showed that EtOH/HCl treatment produced mucosal injuries with morphological and histological damage, whereas EtGR co-treatment reduced the gastric injuries. EtGR treatment also decreased the contents of malonaldehyde (MDA) activity relative to the vehicle group. Moreover, EtGR decreased the levels of interleukin-1β (IL-1β), interleukin-6 (IL-6) and cyclo-oxygenase-2 (COX-2) expression. Finally, EtGR did not induce any specific toxicity in the livers or kidneys of the EtOH/HCl-induced gastric ulcer model. These results suggest that EtGR had stronger antioxidant activity and could be a new useful natural drug for gastroprotection against gastric ulcer. Moreover, these findings provide a scientific basis for the development of drugs from traditional oriental herbal medicines.

Gastroprotective effect of calealactone B: Lack of involvement of prostaglandins, nitric oxide and sulfhydryls

Hit, Lead & Candidate Discovery The gastroprotective effect of calealactone B, isolated from Calea urticifolia was assessed in an ethanol-induced model of gastric lesioning. The possible involvement of prostaglandins, nitric oxide (NO) and sulfhydryl groups in the mechanism of action of calealactone B was also assessed. Calealactone B inhibited ethanol-induced gastric injuries with a maximal effect (95.3 ± 2.6%) at 30 mg kg^-1 . A similar value was obtained at 10 mg kg^-1 (83.5 ± 7.7%). Meanwhile, the reference anti-ulcer drug, carbenoxolone, an 11β-hydroxysteroid dehydrogenase (11β-HSD) inhibitor administered at 30 mg kg^-1 showed 63.5 ± 9.4% gastroprotection. Hence, calealactone B was more potent than carbenoxolone. Pretreatment with indomethacin, L-NAME or NEM did not reverse the effects of calealactone B, indicating that prostaglandins, NO and sulfhydryl compounds do not participate in its mechanism of action.

An LC-MS/MS method for quantitation of cyanidin-3-O-glucoside in rat plasma: Application to a comparative pharmacokinetic study in normal and streptozotocin-induced diabetic rats

A sensitive and reliable liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed to determine cyanidin-3-O-glucoside (Cy-3G) in normal and streptozotocin-induced diabetic rat plasma. Chromatographic separation was carried out on a Zorbax SB-C₁₈ (50 × 4.6 mm, 5 μm) column and mass spectrometric analysis was performed using a Thermo Finnigan TSQ Quantum Ultra triple-quadrupole mass spectrometer coupled with an ESI source in the negative ion mode. Selected reaction monitoring mode was applied for quantification using target fragment ions m/z 447.3 → 285.2 for Cy-3G and m/z 463.0 → 300.1 for quercetin-3-O-glucoside (internal standard). The calibration curve was linear over the range 3.00-2700 ng/mL (r²  ≥ 0.99) with the lower limit of quantitation at 3.00 ng/mL. Intra- and inter-day precision was <14.5% and mean accuracy was from -11.5 to 13.6%. Stability testing showed that Cy-3G remained stable during the whole analytical procedure. After validation, the assay was successfully used to support a preclinical pharmacokinetic comparison of Cy-3G between normal and diabetic rats. Results indicated that diabetes mellitus significantly altered the in vivo pharmacokinetic characteristics of Cy-3G after oral administration in rats.

The effects of baicalein on gastric mucosal ulcerations in mice: Protective pathways and anti-secretory mechanisms

Many flavonoids have been shown to present good results for the treatment of gastric ulcers. Baicalein, a bioactive flavonoid derived from the Scutellaria baicalensis Georgi root, possesses several biological effects, such as anti-inflammatory and antioxidant. This study was conducted to assess the gastroprotective properties of baicalein. Anti-ulcerogenic assay was performed using the protocol of ulcer induced by ethanol/HCl in mice; then, the role of presynaptic α₂-receptors, sulfhydryl (SH) compounds, nitric oxide (NO), prostaglandin (PG) and ATP-sensitive K⁺ (K_ATP) channels in gastroprotection of baicalein was investigated. The levels of reduced glutathione (GSH) and the myeloperoxidase (MPO) activity were measured in the gastric mucosa. Parameters of gastric secretion (volume, [H⁺] and pH) were determined with or without the presence of the secretagogue agent histamine, as well as mucus in gastric contents, by the pylorus ligation model. In vitro H⁺,K⁺-ATPase activity was also determined. Baicalein (10, 30 and 100 mg/kg) exhibited a dose related gastroprotective effect (P < 0.001) against acidified ethanol-induced lesions. The intraperitoneal treatment of mice with a α₂-adrenoreceptor antagonist (yohimbine; 2 mg/kg), a SH compounds blocker (N-ethylmaleimide, NEM; 10 mg/kg), a non-selective inhibitor of NO synthase (N_w-nitro-L-arginine methyl ester hydrochloride, L-NAME; 10 mg/kg), a non-selective inhibitor of cyclo-oxygenase (indomethacin; 10 mg/kg) or a K_ATP channel blocker (glibenclamide; 10 mg/kg) was able to reverse (P < 0.001) the gastroprotective response caused by baicalein (30 mg/kg). Baicalein (30 mg/kg; P < 0.05) was able to increase GSH levels and decreasing MPO activity. The intraduodenal treatment with baicalein (30 and 100 mg/kg) significantly increased (P < 0.05) the gastric mucus secretion. Additionally, the treatment with baicalein reduced (30 and 100 mg/kg; P < 0.05) the secretion volume and total acid secretion, and also increased (10, 30 and 100 mg/kg; P < 0.001) the pH value, after pylorus ligature. Baicalein (30 mg/kg) was also effective in inhibiting the effects of histamine on gastric secretion (volume, [H⁺] and pH; P < 0.001). Baicalein at 10 and 30 μg/mL showed anti-H⁺,K⁺-ATPase activity. In conclusion, the present results provide convincing evidence that baicalein could be used as a cytoprotective (preventive effect) and anti-ulcerogenic (anti-secretory effect) agent in the gastric ulcers.

Gastroprotective xanthones isolated from Garcinia achachairu: Study on mucosal defensive factors and H(+), K(+)-ATPase activity

The present study was designed to investigate the gastroprotective effect of xanthones 7-preniljacareubin (PJB), 1,3,5,6-tetrahydroxy xanthone (THX), 3-demethyl-2-geranyl-4-prenylbellidypholine (DGP) and 1,5,8-trihydroxy-4', 5'-dimethyl-2H-pyrane (2,3:3,2)-4-(3-methylbut-2-enyl) xanthone (TDP) isolated of branches from G. achachairu. Their structures were identified through the spectroscopic analysis in comparison with previously reported data. The xanthones were tested at dose of 10 mg/kg against ethanol 60%/HCl 0.3 N-induced gastric ulcer in female swiss mice. The xanthones PJB, THX, DGP and TDP exhibit gastroprotective effect after intraperitoneal treatment, but only the first two displayed anti-ulcer activity after oral administration. Both PJB and THX augmented the antioxidative capacity of tissue by an increase in glutathione levels, as well as were able to prevent an increase in myeloperoxidase activity and tumor necrosis factor level. On the other hand, only THX showed an in vitro free radical scavenger activity, and only PJB avoided mucus depletion on gastric mucosa, which was not associated with an increase in mucin production at glandular level. In addition, PJB and THX inhibited the in vitro H(+)K(+)-ATPase activity at similar range as omeprazole. Together, these results demonstrate the anti-ulcer efficacy of xanthones isolated from G. achachairu, which can contribute for future directions in the development of effective strategies to improve gastric diseases.

Protective activity of salidroside against ethanol-induced gastric ulcer via the MAPK/NF-κB pathway in vivo and in vitro

Salidroside (Sal) is a traditional Chinese medicine with various pharmacological effects. The present study aimed to investigate the protective effect of Sal on ethanol-induced acute gastric ulcer and H2O2-induced gastric epithelial cell damage. 0.2 ml ethanol and 400 μM H2O2 were applied to establish a gastric ulcer model in vivo and in vitro respectively. The production of interleukin (IL)-6, interleukin (IL)-1β and tumor necrosis factor (TNF)-α was analyzed, as well as myeloperoxidase (MPO), malondialdehyde (MDA) and superoxide dismutase (SOD). MTT assay was used to detect cell viability. In addition, MAPK/NF-κB signal pathway-related proteins p-ERK, p-JNK, p-p38, p-IκBα and p-NF-κBp65 were analyzed to determine the underlying protective mechanism. Downstream genes such as cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX) and leukotrienes B4 (LTB4) were also measured. Obtained data indicated that Sal inhibited the overproduction of pro-inflammatory cytokines and enhanced antioxidant activity. Collectively, it is assumed that Sal could alleviate ethanol-induced acute gastric ulcer and H2O2-induced gastric epithelial cell damage through the MAPK/NF-κB pathway.

Evaluation of antioxidant, anti-inflammatory, and antiulcer properties of Vaccinium leschenaultii Wight: A therapeutic supplement

In folklore systems of medicine, bilberry fruit and leaf extracts have been used for the treatment of diarrhoea, dysentery, diabetes, inflammation, and ulcer. The present study was to determine antioxidant, anti-inflammatory, and antiulcerogenic activities of Vaccinium leschenaultii Wight leaf and fruit. The phenolic, tannin, and flavonoid contents of V. leschenaultii leaf and fruit were quantified and were subjected to assess their antioxidant potential using various in vitro systems such as 1, 1 diphenyl-2-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging, phosphomolybdenum, and ferric reducing antioxidant power reduction activities. Based on the antioxidant potential, acetone and methanol extracts of leaf and fruit were used to evaluate the anti-inflammatory activity and protective effect against ethanol-induced gastric damage in a rat model. The quantification of secondary metabolites shows that the phenolic, flavonoid, and tannin contents are higher in methanol extracts of fruit and leaf. The results of antioxidant assays exhibited that the methanol extracts of leaf possesses better 1, 1 diphenyl-2-picrylhydrazyl radical scavenging and ferric reducing power activity. Oral administration of the acetone fruit and leaf extracts of V. leschenaultii were capable of reducing the edema formation in rats against carrageenan and egg albumin induced inflammation. Moreover, leaf and fruit acetone extracts at the dose of 400 mg/kg highly inhibited ulcer formation. The study concluded that the plant substances such as total phenols, flavonoids along with appreciable antioxidant potential could be the supportive evidence to prove both the anti-inflammatory and antiulcer activities of V. leschenaultii. The traditional importance of this plant will help to reveal the potential of plant to provide alternative phytotherapeutics for human health.

Mucoadhesive microparticles for gastroretentive delivery: preparation, biodistribution and targeting evaluation

The aim of this research was to prepare and characterize alginate-chitosan mucoadhesive microparticles containing puerarin. The microparticles were prepared by an emulsification-internal gelatin method using a combination of chitosan and Ca²⁺ as cationic components and alginate as anions. Surface morphology, particle size, drug loading, encapsulation efficiency and swelling ratio, in vitro drug released, in vitro evaluation of mucoadhesiveness and Fluorescence imaging of the gastrointestinal tract were determined. After optimization of the formulation, the encapsulation efficiency was dramatically increased from 70.3% to 99.2%, and a highly swelling ratio was achieved with a change in particle size from 50.3 ± 11.2 μm to 124.7 ± 25.6 μm. In ethanol induced gastric ulcers, administration of puerarin mucoadhesive microparticles at doses of 150 mg/kg, 300 mg/kg, 450 mg/kg and 600 mg/kg body weight prior to ethanol ingestion significantly protected the stomach ulceration. Consequently, significant changes were observed in inflammatory cytokines, such as prostaglandin E₂ (PGE₂), tumor necrosis factor (TNF-α), interleukin 6 (IL-6), and interleukin1β (IL-1β), in stomach tissues compared with the ethanol control group. In conclusion, core-shell type pH-sensitive mucoadhesive microparticles loaded with puerarin could enhance puerarin bioavailability and have the potential to alleviate ethanol-mediated gastric ulcers.

Anti-ulcerogenic effect of methanolic extracts from Enicosanthellum pulchrum (King) Heusden against ethanol-induced acute gastric lesion in animal models

A natural source of medicine, Enicosanthellum pulchrum is a tropical plant which belongs to the family Annonaceae. In this study, methanol extract from the leaves and stems of this species was evaluated for its gastroprotective potential against mucosal lesions induced by ethanol in rats. Seven groups of rats were assigned, groups 1 and 2 were given Tween 20 (10% v/v) orally. Group 3 was administered omeprazole 20 mg/kg (10% Tween 20) whilst the remaining groups received the leaf and stem extracts at doses of 150 and 300 mg/kg, respectively. After an additional hour, the rats in groups 2-7 received ethanol (95% v/v; 8 mL/kg) orally while group 1 received Tween 20 (10% v/v) instead. Rats were sacrificed after 1 h and their stomachs subjected to further studies. Macroscopically and histologically, group 2 rats showed extremely severe disruption of the gastric mucosa compared to rats pre-treated with the E. pulchrum extracts based on the ulcer index, where remarkable protection was noticed. Meanwhile, a significant percentage of inhibition was shown with the stem extract at 62% (150 mg/kg) and 65% (300 mg/kg), whilst the percentage with the leaf extract at doses of 150 and 300 mg/kg was 63% and 75%, respectively. An increase in mucus content, nitric oxide, glutathione, prostaglandin E2, superoxide dismutase, protein and catalase, and a decrease in malondialdehyde level compared to group 2 were also obtained. Furthermore, immunohistochemical staining of groups 4-7 exhibited down-regulation of Bax and up-regulation of Hsp70 proteins. The methanol extract from the leaves and the stems showed notable gastroprotective potential against ethanol.

Role of an indole-thiazolidine molecule PPAR pan-agonist and COX inhibitor on inflammation and microcirculatory damage in acute gastric lesions

The present study aimed to show the in vivo mechanisms of action of an indole-thiazolidine molecule peroxisome-proliferator activated receptor pan-agonist (PPAR pan) and cyclooxygenase (COX) inhibitor, LYSO-7, in an ethanol/HCl-induced (Et/HCl) gastric lesion model. Swiss male mice were treated with vehicle, LYSO-7 or Bezafibrate (p.o.) 1 hour before oral administration of Et/HCl (60%/0.03M). In another set of assays, animals were injected i.p. with an anti-granulocyte antibody, GW9962 or L-NG-nitroarginine methyl ester (L-NAME) before treatment. One hour after Et/HCl administration, neutrophils were quantified in the blood and bone marrow and the gastric microcirculatory network was studied in situ. The gastric tissue was used to quantify the percentage of damaged area, as well as myeloperoxidase (MPO), inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS) protein and PPARγ protein and gene expression. Acid secretion was evaluated by the pylorus ligation model. LYSO-7 or Bezafibrate treatment reduced the necrotic area. LYSO-7 treatment enhanced PPARγ gene and protein expression in the stomach, and impaired local neutrophil influx and stasis of the microcirculatory network caused by Et/HCl administration. The effect seemed to be due to PPARγ agonist activity, as the LYSO-7 effect was abolished in GW9962 pre-treated mice. The reversal of microcirculatory stasis, but not neutrophil influx, was mediated by nitric oxide (NO), as L-NAME pre-treatment abolished the LYSO-7-mediated reestablishment of microcirculatory blood flow. This effect may depend on enhanced eNOS protein expression in injured gastric tissue. The pH and concentration of H⁺ in the stomach were not modified by LYSO-7 treatment. In addition, LYSO-7 may induce less toxicity, as 28 days of oral treatment did not induce weight loss, as detected in pioglitazone treated mice. Thus, we show that LYSO-7 may be an effective treatment for gastric lesions by controlling neutrophil influx and microcirculatory blood flow mediated by NO.

Date fruit: chemical composition, nutritional and medicinal values, products

Date fruit has served as a staple food in the Arab world for centuries. Worldwide production of date fruit has increased almost threefold over the last 40 years, reaching 7.68 million tons in 2010. Date fruit can provide many essential nutrients and potential health benefits to the consumer. Date fruit goes through four ripening stages named kimri, khalal, rutab and tamer. The main chemical components of date fruit include carbohydrates, dietary fibre, enzymes, protein, fat, minerals, vitamins, phenolic acids and carotenoids. The chemical composition of date fruit varies according to ripening stage, cultivar, growing environment, postharvest conditions, etc. The nutritional and medicinal activities of date fruit are related to its chemical composition. Many studies have shown that date fruit has antioxidant, antimutagenic, anti-inflammatory, gastroprotective, hepatoprotective, nephroprotective, anticancer and immunostimulant activities. Various date fruit-based products such as date syrup, date paste, date juice and their derived products are available. Date by-products can be used as raw materials for the production of value-added products such as organic acids, exopolysaccharides, antibiotics, date-flavoured probiotic-fermented dairy produce, bakery yeasts, etc. In this paper the chemical composition and nutritional and medicinal values of date fruit as well as date fruit-based products are reviewed.

Pyranocycloartobiloxanthone A, a novel gastroprotective compound from Artocarpus obtusus Jarret, against ethanol-induced acute gastric ulcer in vivo

Pyranocycloartobiloxanthone A (PA), a xanthone derived from the Artocarpus obtusus Jarret, belongs to the Moraceae family which is native to the tropical forest of Malaysia. In this study, the efficacy of PA as a gastroprotective compound was examined against ethanol-induced ulcer model in rats. The rats were pretreated with PA and subsequently exposed to acute gastric lesions induced by absolute ethanol. The ulcer index, gastric juice acidity, mucus content, histological analysis, glutathione (GSH) levels, malondialdehyde level (MDA), nitric oxide (NO) and non-protein sulfhydryl group (NP-SH) contents were evaluated in vivo. The activities of PA as anti-Helicobacter pylori, cyclooxygenase-2 (COX-2) inhibitor and free radical scavenger were also investigated in vitro. The results showed that the oral administration of PA protects gastric mucosa from ethanol-induced gastric lesions. PA pretreatment significantly (p<0.05) restored the depleted GSH, NP-SH and NO levels in the gastric homogenate. Moreover, PA significantly (p<0.05) reduced the elevated MDA level due to ethanol administration. The gastroprotective effect of PA was associated with an over expression of HSP70 and suppression of Bax proteins in the ulcerated tissue. In addition, PA exhibited a potent FRAP value and significant COX-2 inhibition. It also showed a significant minimum inhibitory concentration (MIC) against H. pylori bacterium. The efficacy of PA was accomplished safely without the presence of any toxicological parameters. The results of the present study indicate that the gastroprotective effect of PA might contribute to the antioxidant and anti-inflammatory properties as well as the anti-apoptotic mechanism and antibacterial action against Helicobacter pylori.

Protective effect of ethyl acetate fraction of Acacia ferruginea DC. against ethanol-induced gastric ulcer in rats

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional systems of medicine, stem bark of Acacia ferruginea DC. is used for the treatment of itching, leucoderma, ulcers, stomatitis and diseases of the blood. In the present study, we determined antioxidant and anti-ulcerogenic activities of Acacia ferruginea stem bark.

MATERIALS AND METHODS

Acetone extract and its sub-fractions of Acacia ferruginea stem bark were subjected to assess their antioxidant potential using various in vitro systems such as DPPH(•), ABTS(•+) scavenging, FRAP and phosphomolybdenum reduction activities. Based on the antioxidant potential, the ethyl acetate fraction was used to evaluate the protective effect of ethanol-induced gastric damage in rat model. Enzyme activities such as superoxide dismutase, glutathione, catalase and lipid peroxidation were also determined in the stomach tissues.

RESULTS

Ethyl acetate fraction (AFE) of Acacia ferruginea stem bark registered higher antioxidant and free radical scavenging activities than the crude acetone extract and other fractions. In addition, AFE exhibited that the IC50 values of DPPH (2.5µg/ml) and ABTS (1.8µg/ml) were lower when compared to the standard quercetin (12.4µg/ml and 4.7µg/ml, respectively). In ethanol induced gastric ulcer, administration of AFE at doses of 10mg/kg, 50mg/kg and 100mg/kg body weight prior to ethanol ingestion significantly protected the stomach ulceration. Consequently significant changes were observed in enzyme activities such as SOD, CAT, GSH and LPO in the stomach tissues when compared with ethanol control group.

CONCLUSION

It is concluded that the ethyl acetate fraction of Acacia ferruginea stem bark possessed higher antioxidant and anti-ulcerogenic activities. Based on the results, we suggest that Acacia ferruginea stem bark has potential to provide a therapeutic approach to ethanol mediated ulcer as an effective anti-ulcer agent.

Dietary nitrate and reductive polyphenols may potentiate the vascular benefit and alleviate the ulcerative risk of low-dose aspirin

The recent revelation that daily low-dose aspirin not only lowers risk for vascular events, but also can notably decrease risk for a range of adenocarcinomas, decreasing total cancer mortality by about 20%, makes it highly desirable to implement this protective strategy on a population-wide basis. Nonetheless, the fact that low-dose aspirin approximately doubles risk for serious gastrointestinal bleeding may impede health authorities from recommending its use by people judged to be at low cardiovascular risk. Nitric oxide (NO) exerts gastroprotective effects by boosting blood flow and mucus production in the gastric mucosa - effects which demonstrably oppose the pro-ulcerative impact of aspirin and other NSAIDs. A nitrate-rich diet, as well as ingestion of reductive catechol-bearing polyphenols, can collaborate in promoting NO generation in gastric juice, and they are protective in rodent models of gastric ulceration. Moreover, a high-nitrate diet, as well as certain reductive polyphenols such as epicatechin and quercetin, can exert platelet-stabilizing effects complementary to those of aspirin, and act in other ways to preserve vascular health. Hence, diets rich in nitrate and reductive polyphenols have the potential to amplify the vascular-protective benefits of low-dose aspirin, while diminishing its pro-ulcerative risk. Low-dose aspirin may be more unequivocally recommendable within the context of such a dietary strategy.

Protective effect of extract from Rumex aquaticus herba on ethanol-induced gastric damage in rats

BACKGROUND/AIMS

In this study, we investigated the gastroprotective effect of extract including quercetin-3-O-β-D-glucuronopyranoside (EIQ) from Rumex aquaticus herba against the ethanol-induced gastric damage in rats.

METHODS

The rats were divided into eight groups composed of a non-ethanol group, only EIQ (10 mg/kg) group, groups with absolute ethanol after pretreatment with various doses of EIQ (1, 3 and 10 mg/kg), rebamipide (10 mg/kg), stillen (40 mg/kg) and a control receiving only absolute ethanol. Ethanol-induced gastric lesions, lipid peroxidation, neutrophil infiltration and glutathione level were measured. Superoxide dismutase (SOD) and catalase activity were assessed by an assay kit. Protein expression of SOD, catalase or hemoxygenase-1 (HO-1) was assessed by western blotting analysis.

RESULTS AND CONCLUSION

In the absolute ethanol treated group, gastric lesion and malondialdehyde levels were significantly increased with enhanced myeloperoxidase activity. Administration of EIQ 1 h prior to ethanol treatment significantly inhibited the formation of gastric lesions and the elevation of the malondialdehyde levels with myeloperoxidase activity. In addition, pretreatment with EIQ significantly increased the level of glutathione, and elevated the activity and protein expression of radical scavenging enzymes, such as SOD, catalase and HO-1. EIQ may exert anti-inflammatory and anti-oxidative effects against ethanol-induced gastric injury through the reduction of lipid peroxidation, myeloperoxidase activity and free radicals.

Morphologic and pharmacological investigations in the epicatechin gastroprotective effect

Previous studies of the gastroprotective activity of plants have highlighted the importance of the polyphenolic compound epicatechin (EC) in the treatment of gastric ulcers. This paper aimed to evaluate and characterize the gastroprotective mechanism of action of EC using male rats. The gastroprotective action of EC was analyzed in gastric ulcers induced by ethanol or indomethacin. The involvement of sulfhydryl (SH) groups, K⁺_ATP channels, α₂ adrenoceptors, gastric antisecretory activity, and the amount of mucus in the development of gastric ulcers were investigated. The lowest effective dose of EC providing gastroprotective effects was 50 mg/kg in the ethanol-induced gastric ulcers and 25 mg/kg in the indomethacin-induced gastric ulcers. The gastroprotection seen upon treatment with EC was significantly decreased in rats pretreated with a SH compound reagent or an α₂-receptor antagonist, but not with a K⁺_ATP channel blocker. Furthermore, oral treatment with EC increased mucus production and decreased H⁺ secretion. Immunohistochemistry demonstrated the involvement of superoxide dismutase (SOD), nitric oxide (NO), and heat shock protein-70 (HSP-70) in the gastroprotection. These results demonstrate that EC provides gastroprotection through reinforcement of the mucus barrier and neutralization of gastric juice and this protection occurs through the involvement of SH compounds, α₂-adrenoceptors, NO, SOD, and HSP-70.

Evaluation of antioxidant and antiulcerogenic activities of Opuntia ficus indica f. inermis flowers extract in rats

The Opuntia ficus indica f. inermis methanolic flowers extract (OMFE) was phytochemical studied, in vitro tested for their potential antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH), reducing power, linoleic acid peroxidation assays and in vivo evaluated for its ability to prevent ethanol-induced gastric ulcer in rats. The OMFE was rich in polysaccharide, phenolics and flavonoids contents and exhibited a moderate in vitro antioxidant activity when compared with (+)-catechin and ascorbic acid. Pre-treatment with OMFE at oral doses 250, 500 and 1000 mg/kg body weight was found to provide a dose-dependent protection against ethanol-induced gastric ulcer by averting the deep necrotic lesions of the gastric epithelium, by preserving normal antioxidant enzymes activities, by inhibiting the lipid peroxidation, the oxidation of protein and the DNA fragmentation in gastric mucosa. The antiulcerogenic activity of OMFE might be due to a possible synergistic antioxidant and antihistaminic-like effects.

Strawberry polyphenols attenuate ethanol-induced gastric lesions in rats by activation of antioxidant enzymes and attenuation of MDA increase

Background and Aim

Free radicals are implicated in the aetiology of gastrointestinal disorders such as gastric ulcer, colorectal cancer and inflammatory bowel disease. Strawberries are common and important fruit due to their high content of essential nutrient and beneficial phytochemicals which seem to have relevant biological activity on human health. In the present study we investigated the antioxidant and protective effects of three strawberry extracts against ethanol-induced gastric mucosa damage in an experimental in vivo model and to test whether strawberry extracts affect antioxidant enzyme activities in gastric mucosa.

Methods/Principal Findings

Strawberry extracts were obtained from Adria, Sveva and Alba cultivars. Total antioxidant capacity and radical scavenging capacity were performed by TEAC, ORAC and electron paramagnetic resonance assays. Identification and quantification of anthocyanins was carried out by HPLC-DAD-MS analyses. Different groups of animals received 40 mg/day/kg body weight of strawberry crude extracts for 10 days. Gastric damage was induced by ethanol. The ulcer index was calculated together with the determination of catalase and SOD activities and MDA contents. Strawberry extracts are rich in anthocyanins and present important antioxidant capacity. Ethanol caused severe gastric damage and strawberry consumption protected against its deleterious role. Antioxidant enzyme activities increased significantly after strawberry extract intake and a concomitantly decrease in gastric lipid peroxidation was found. A significant correlation between total anthocyanin content and percent of inhibition of ulcer index was also found.

Conclusions

Strawberry extracts prevented exogenous ethanol-induced damage to rats' gastric mucosa. These effects seem to be associated with the antioxidant activity and phenolic content in the extract as well as with the capacity of promoting the action of antioxidant enzymes. A diet rich in strawberries might exert a beneficial effect in the prevention of gastric diseases related to generation of reactive oxygen species.

Cyanidin-3-glucoside ameliorates ethanol neurotoxicity in the developing brain

Ethanol exposure induces neurodegeneration in the developing central nervous system (CNS). Fetal alcohol spectrum disorders (FASD) are caused by ethanol exposure during pregnancy and are the most common nonhereditary cause of mental retardation. It is important to identify agents that provide neuroprotection against ethanol neurotoxicity. Multiple mechanisms have been proposed for ethanol-induced neurodegeneration, and oxidative stress is one of the most important mechanisms. Recent evidence indicates that glycogen synthase kinase 3β (GSK3β) is a potential mediator of ethanol-mediated neuronal death. Cyanidin-3-glucoside (C3G), a member of the anthocyanin family, is a potent natural antioxidant. Our previous study suggested that C3G inhibited GSK3β activity in neurons. Using a third trimester equivalent mouse model of ethanol exposure, we tested the hypothesis that C3G can ameliorate ethanol-induced neuronal death in the developing brain. Intraperitoneal injection of C3G reduced ethanol-meditated caspase-3 activation, neurodegeneration, and microglial activation in the cerebral cortex of 7-day-old mice. C3G blocked ethanol-mediated GSK3β activation by inducing phosphorylation at serine 9 while reducing the phosphorylation at tyrosine 216. C3G also inhibited ethanol-stimulated expression of malondialdehyde (MDA) and p47phox, indicating that C3G alleviated ethanol-induced oxidative stress. These results provide important insight into the therapeutic potential of C3G.

Dietary freeze-dried black raspberry's effect on cellular antioxidant status during reflux-induced esophagitis in rats

INTRODUCTION

Esophageal cancer consists of two distinct types, esophageal adenocarcinoma (EAC) and squamous cell carcinoma, both of which differ significantly in their etiology. Freeze-dried black raspberry (BRB) has been consistent in its ability to modulate the biomarkers and reduce the incidence of carcinogen-induced squamous cell carcinoma in rats. In our previous studies in the esophagoduodenal anastomosis (EDA) model, we have shown that the early modulation of manganese superoxide dismutase (MnSOD) significantly correlates with the development of reflux-induced EAC in rats. In this study we looked at the short-term effects of a BRB-supplemented diet on the modulation of antioxidant enzymes in reflux-induced esophagitis.

METHODS

Male SD rats (8 wk old; n = 3-5) were randomized into three groups--sham-operated, fed control AIN-93M diet (SH-CD), EDA operated and fed either control diet (EDA-CD) or 2.5% (w/w) BRB diet (EDA-BRB). The effect of both reflux and dietary supplementation was analyzed 2 and 4 wk after EDA surgery.

RESULTS

Animals in the EDA groups had significantly lower weight gain and diet intake compared to SH-CD (P < 0.05). The sham-operated animals received an average esophagitis score of 0.1 ± 0.1; this increased significantly in EDA-CD animals to 1.8 ± 0.14 (P < 0.001 versus SH-CD) and in EDA-BRB group to 1.7 ± 0.06 (P < 0.001 versus SH-CD), with BE changes also present. However, dietary supplementation of BRB did not alter or ameliorate the grade of esophagitis or the induction of BE. BRB diet caused a 43% increase in MnSOD levels compared to EDA-CD (0.73 ± 0.16; P = 0.09); however, this effect was not statistically significant and at 4 wk, EDA-CD (0.58 ± 0.12) showed an increase in MnSOD expression compared to SH-CD (0.34 ± 0.01).

CONCLUSIONS

In conclusion, our data suggest that dietary BRB does not increase the levels of cellular antioxidant enzymes or reduce the levels of lipid peroxidation compared to a control diet, in a short-term study of gastroesophageal reflux induction in the EDA animal model. However, it remains to be tested whether this is indicative of its ineffectiveness to inhibit reflux-induced EAC incidence over the long term.

Anthocyanins: are they beneficial in treating ethanol neurotoxicity?

Heavy alcohol exposure produces profound damage to the developing central nervous system (CNS) as well as the adult brain. Children with fetal alcohol spectrum disorders (FASD) have a variety of cognitive, behavioral, and neurological impairments. FASD currently represents the leading cause of mental retardation. Excessive alcohol consumption is associated with Wernicke-Korsakoff syndrome (WKS) and neurodegeneration in the adult brain. Although the cellular/molecular mechanism underlying ethanol's neurotoxicity has not been fully understood, it is generally believed that oxidative stress plays an important role. Identification of neuroprotective agents that can ameliorate ethanol neurotoxicity is an important step for developing preventive/therapeutic strategies. Targeting ethanol-induced oxidative stress using natural antioxidants is an attractive approach. Anthocyanins, a large subgroup of flavonoids present in many vegetables and fruits, are safe and potent antioxidants. They exhibit diverse potential health benefits including cardioprotection, anti-atherosclerotic activity, anti-cancer, anti-diabetic, and anti-inflammation properties. Anthocyanins can cross the blood-brain barrier and distribute in the CNS. Recent studies indicate that anthocyanins represent novel neuroprotective agents and may be beneficial in ameliorating ethanol neurotoxicity. In this review, we discuss the evidence and potential of anthocyanins in alleviating ethanol-induced damage to the CNS. Furthermore, we discuss possible underlying mechanisms as well as future research approaches necessary to establish the therapeutic role of anthocyanins.