Pathogenesis of NSAID-induced gastric damage: Importance of cyclooxygenase inhibition and gastric hypermotility

Mechanistic evaluation of gastro-protective effects of KangFuXinYe on indomethacin-induced gastric damage in rats

KangFuXinYe (KFX), the ethanol extract of the dried whole body of Periplaneta americana, is a well-known important Chinese medicine preparation that has been used to treat digestive diseases such as gastric ulcers for many years in China. However, its therapeutic effect and mechanism are not yet well understood. Thus, the aim of this study was to investigate the gastro-protective effects of KangFuXinYe (KFX) in indomethacin-induced gastric damage. Rats were randomly divided into six groups as follows: control, treated with indomethacin (35 mg·kg^-1), different dosages of KFX (2.57, 5.14 and 10.28 mL·kg^-1, respectively) plus indomethacin, and sucralfate (1.71 mL·kg^-1) plus indomethacin. After treatment, rat serum, stomach and gastric homogenates were collected for biochemical tests and examination of histopathology firstly. Rat serum was further used for metabolomics analysis to research possible mechanisms. Our results showed that KFX treatment alleviated indomethacin-induced histopathologic damage in rat gastric mucosa. Meanwhile, its treatment significantly increased cyclooxygenase-1 (COX-1), prostaglandin E₂ (PGE₂) and epidermal growth factor (EGF) levels in rat serum and gastric mucosa. Moreover, KFX decreased cyclooxygenase-2 (COX-2) and interleukin-6 (IL-6) levels. Nine metabolites were identified which intensities significantly changed in gastric damage rats, including 5-hydroxyindoleacetic acid, indoxylsulfuric acid, indolelactic acid, 4-hydroxyindole, pantothenic acid, isobutyryl carnitine, 3-methyl-2-oxovaleric acid, sphingosine 1-phosphate, and indometacin. These metabolic deviations came to closer to normal levels after KFX intervention. The results indicate that KFX (10.28 mL·kg^-1) exerts protective effects on indomethacin-induced gastric damage by possible mechanisms of action (regulating tryptophan metabolism, protecting the mitochondria, and adjusting lipid metabolism, and reducing excessive indomethacin).

Potential Role of Tocotrienols on Non-Communicable Diseases: A Review of Current Evidence

Tocotrienol (T3) is a subfamily of vitamin E known for its wide array of medicinal properties. This review aimed to summarize the health benefits of T3, particularly in prevention or treatment of non-communicable diseases (NCDs), including cardiovascular, musculoskeletal, metabolic, gastric, and skin disorders, as well as cancers. Studies showed that T3 could prevent various NCDs, by suppressing 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) in the mevalonate pathway, inflammatory response, oxidative stress, and alternating hormones. The efficacy of T3 in preventing/treating these NCDs is similar or greater compared to tocopherol (TF). TF may lower the efficacy of T3 because the efficacy of the combination of TF and T3 was lower than T3 alone in some studies. Data investigating the effects of T3 on osteoporosis, arthritis, and peptic ulcers in human are limited. The positive outcomes of T3 treatment obtained from the preclinical studies warrant further validation from clinical trials.

Biological characterization of new inhibitors of microsomal PGE synthase-1 in preclinical models of inflammation and vascular tone

BACKGROUND AND PURPOSE

Microsomal PGE synthase-1 (mPGES-1), the inducible synthase that catalyses the terminal step in PGE₂ biosynthesis, is of high interest as therapeutic target to treat inflammation. Inhibition of mPGES-1 is suggested to be safer than traditional NSAIDs, and recent data demonstrate anti-constrictive effects on vascular tone, indicating new therapeutic opportunities. However, there is a lack of potent mPGES-1 inhibitors lacking interspecies differences for conducting in vivo studies in relevant preclinical disease models.

EXPERIMENTAL APPROACH

Potency was determined based on the reduction of PGE₂ formation in recombinant enzyme assays, cellular assay, human whole blood assay, and air pouch mouse model. Anti-inflammatory properties were assessed by acute paw swelling in a paw oedema rat model. Effect on vascular tone was determined with human ex vivo wire myography.

KEY RESULTS

We report five new mPGES-1 inhibitors (named 934, 117, 118, 322, and 323) that selectively inhibit recombinant human and rat mPGES-1 with IC₅₀ values of 10-29 and 67-250 nM respectively. The compounds inhibited PGE₂ production in a cellular assay (IC₅₀ values 0.15-0.82 μM) and in a human whole blood assay (IC₅₀ values 3.3-8.7 μM). Moreover, the compounds blocked PGE₂ formation in an air pouch mouse model and reduced acute paw swelling in a paw oedema rat model. Human ex vivo wire myography analysis showed reduced adrenergic vasoconstriction after incubation with the compounds.

CONCLUSION AND IMPLICATIONS

These mPGES-1 inhibitors can be used as refined tools in further investigations of the role of mPGES-1 in inflammation and microvascular disease.

Alanyl-glutamine Heals Indomethacin-induced Gastric Ulceration in Rats Via Antisecretory and Anti-apoptotic Mechanisms

OBJECTIVES

Alanylglutamine (AG) is a dipeptide that fuels enterocytes and has a coadjuvant role during gut healing. The current study aimed to investigate the potential ulcer-healing effect of AG in indomethacin-induced gastropathy.

METHODS

Animals (n = 10 rats/group) were randomly allocated into 5 groups. Gastric ulcerated rats were administered AG, AG + dexamethasone, or pantoprazole after indomethacin exposure.

RESULTS

Comparable to pantoprazole, AG inhibited H-KATPase pump, and elevated the pH of gastric juice. Moreover, the dipeptide increased the serum/mucosal contents of glucagon-like peptide-1 (GLP-1), pS473-Akt, and cyclin-D1. On the contrary, AG abated serum tumor necrosis factor-α and gastric mucosal content of pS45-β catenin, pS9-GSK3β, pS133-CREB, pS536-NF-κB, H2O2, claudin-1, and caspase-3. The administration of dexamethasone before AG hampered its effect on almost all the measured parameters.

CONCLUSIONS

AG confers its antiulcerogenic/antisecretory potentials by repressing the proton pump to increase the gastric juice pH via boosting p-CREB, p-Akt, p-GSK-3β, and GLP-1. Also, it inhibits apoptosis through suppressing nuclear factor-kappa B/tumor necrosis factor-α/H2O2/claudin-1 cue. This trajectory contributes to loosen the tight junction priming AG-mediated GLP-1/β-catenin/cyclin-D1 that results in pronounced increase in gastric mucosa proliferation. Therefore, the crosstalk between multiple pathways orchestrates the action of AG against gastric ulceration.

A Botanical-Based Equine Nutraceutical Reduces Gastric Smooth Muscle Contractile Force In Vitro

The objective of this study was to evaluate the effect of a botanical-based equine nutraceutical on contractility of gastric smooth muscle in vitro. Gastric ulcers are prevalent in performance horses and negatively impact horse welfare. Gastric hypermotility has been positively associated with the development of gastric ulceration in nonequine species, and reduction of hypermotility may be protective against their development. Stomachs from 12 pigs processed for food at a provincially inspected abattoir were collected within 1 hour of slaughter. Explants of nonglandular gastric tissue were prepared and suspended in a tissue bath, attached to a force transducer, in the presence or absence of a simulated digest extract of the nutraceutical. Tissue was stimulated to contract using increasing doses of acetylcholine. Peak and mean contractile force over 1 and 2 minutes after exposure to acetylcholine were measured. Exposure of gastric smooth muscle to the nutraceutical significantly reduced contractility of the tissue. These data provide support for the use of this nutraceutical to reduce contractility of nonglandular gastric smooth muscle and may indicate a protective effect of this nutraceutical in horses with mechanically induced gastric ulcers. Future studies are needed to clarify the role of gastric hypermotility on development of equine gastric ulcers and to determine the effect of this nutraceutical on equine gastric contractility and ulcerogenesis in vivo.

Depression and Anxiety Are Risk Factors for Postoperative Pain-Related Symptoms and Complications in Patients Undergoing Primary Total Knee Arthroplasty in the United States

BACKGROUND

The study was designed to analyze the underlying relationship between psychiatric comorbidities and postoperative outcomes in patients undergoing primary total knee arthroplasty (TKA).

METHODS

We used the National Inpatient Sample data from 2002 to 2014. On the basis of the International Classification of Disease, Ninth Revision, Clinical Modification, we divided TKA patients into 4 subgroups: those diagnosed with depression, those diagnosed with anxiety, those concomitantly diagnosed with both depression and anxiety, and those without depression or anxiety. The chi-squared test and analysis of variance were performed to measure differences among these 4 subgroups. Multiple logistic regression analysis was used to determine whether psychological comorbidities were independent risk factors for postoperative complications and surgery-related pain.

RESULTS

A total of 7,153,750 patients in the United States were estimated to have undergone TKA between 2002 and 2014. The prevalence of depression, anxiety, or both diagnoses in TKA patients significantly increased over time. Patients with psychiatric disorders showed higher hospital costs but shorter periods of hospitalization, with higher odds ratios for most complications and all pain-related symptoms observed in this study.

CONCLUSION

The prevalence of depression and anxiety in TKA patients is increasing steadily each year. Psychiatric disorders were closely correlated with the outcomes of TKA. The mental health of patients undergoing TKA needs more attention to ensure adequate relief from postoperative pain-related symptoms as well as quality of life.

Antiulcer activity of Cyperus alternifolius in relation to its UPLC-MS metabolite fingerprint: A mechanistic study

BACKGROUND

Gastric ulcer is one of the main prevalent gastrointestinal multi-etiological disorders with many associated complications and adverse effects. Our aim was to develop safer antiulcer therapies based on methanol or ethyl acetate extracts of tubers and aerial parts from Cyperus alternifolius.

METHODS

Gastric ulceration was experimentally generated by administration of single oral doses of indomethacin (30 mg/kg) to fasted rats. The animals received methanol or ethyl acetate extracts of C. alternifolius tuber and methanol or ethyl acetate extracts of aerial parts at two dose levels (50 or 100 mg/kg). Ranitidine (50 mg/kg) was used as standard anti-ulcer drug. After 4 h, the ulcer number and the total ulcer score were determined and TNF-α was assessed. Also, pathological and histochemical examination for gastric mucosa were performed. The metabolome heterogeneity of the different extracts was explored using (UPLC-MS) aided by supervised pattern recognition, i.e., orthogonal partial least squares discriminate analysis (OPLS-DA). A second OPLS-DA model was employed to link the UPLC-MS derived metabolome of the different extracts to their antiulcer activity to identify activity mediating metabolites.

RESULTS

The extracts significantly reduced ulcer number, total ulcer score and TNF-α content in the stomach. Methanol or ethyl acetate extracts of tubers were most effective even more than ranitidine. In parallel, the histopathological examination showed an improvement of damaged mucosa. A high PAS reaction was observed in the treated groups indicating a relieve of the mucosal layer. A mechanistic clue of the C. alternifolius antiulcer potential was provided by the identification of its bioactive compounds using OPLS-DA. Both methanol extracts of tubers and aerial parts were more enriched in phenolic acids. The ethyl acetate extract of the aerial part was more abundant in two aldehydes. A mechanism of action was postulated based on their reported actions viz. α-carbonic anhydrase inhibition, anti-inflammatory and analgesic activity by its antioxidant activity and downregulation of several inflammatory mediators.

CONCLUSION

This is the first study to report on the antiulcer activity of C. alternifolius tubers with identification of the key bioactive compounds and the mode of action. Future phytochemical and biological evaluation of the identified bioactive compounds are needed to confirm the plant tubers as safer alternative or adjunct therapy compared to conventional antiulcer drugs.

Induction of COX-1, suppression of COX-2 and pro-inflammatory cytokines gene expression by moringa leaves and its aqueous extract in aspirin-induced gastric ulcer rats

The Moringa plant (Moringa oleifera) is known for its potential medicinal properties and health benefits in addition to its high nutritional value. The current study aimed to investigate the antiulcer effect of moringa leaves and its aqueous extract on pro-inflammatory cytokines and inflammatory mediators in ulcerative rats. Rats were treated with either moringa leaves (10%) or moringa extract (300 mg/kg body weight) for 4 weeks then treated with a single dose of aspirin to induce gastric ulcer. Moringa leaves and its extract markedly reduced ulcer index, gastric volume and total acidity. Both treatments induced a significant increase in gastric mucosal mucin content and plasma NO level associated with significant decrease in plasma TNFα. Moringa leaves and its extract prompted down-regulation of TNFα, TGFβ1 and COX2 genes expression by 2.7, 3.5, and 8.4 fold-change for moringa leaves and 2.7, and 2.3, 4.1 fold-change for moringa extract, respectively. Moringa leaves and extract treatments altered the COX-1 gene expression levels to near normal values. This study confirms the gastro-protective influence of moringa leaves and its extract on aspirin-induced ulcer in rats as manifested by its significant reduction in inflammatory cytokines and normalization of gastric mucosal mucin and NO level. Overall, moringa leaves powder is more efficient as antiulcer agent than moringa extract.

The Ocular Surface Glycocalyx and its Alteration in Dry Eye Disease: A Review

Many studies have revealed that transmembrane mucins, large glycoproteins with heavily glycosylated glycans, are essential for maintaining ocular surface epithelium lubrication and wettability. Recent reports indicate that transmembrane mucins and galectin-3, a chimera type of galectin that binds β-galactoside in the glycan, play a crucial role in maintaining the epithelial glycocalyx barrier. This review summarizes current evidence regarding the role of galectin-3, the role of the three major transmembrane mucins (i.e., MUC1, MUC4, and MUC16), in the maintenance of ocular surface wettability and transcellular barrier. Pathological mechanisms of glycocalyx barrier disruption and epithelial surface wettability decreases in dry eye disease are also summarized. Lastly, new ophthalmic drugs that target transmembrane mucin are described.

[Predictors for development of major cardiovascular events in elderly patients with severe and extremely severe chronic obstructive pulmonary disease in combination with early stages of chronic kidney disease]

The aim of the study was to evaluate efficacy, safety and treatment compliance for different ASA forms (Aspirin Cardio, Cardiomagnyl and Trombo Ass) in a 6-month study.

MATERIALS AND METHODS

A prospective 6-month open, comparative study originally included 600 patients with IHD and stable angina who received chronic therapy with different forms of aspirin. In the prospective part of the study, these patients were subdivided into four groups: group 1 consisted of 200 patients switched to Aspirin Cardio; group 2 - 200 pa - tients receiving chronic therapy with this drug; group 3 - 100 patients continuing on the Trombo Ass treatment; and group 4 - 100 pa - tients who had been treated with Cardiomagnyl for a long time. Efficacy, safety and compliance to the treatment were evaluated using standard tests and analogue scales; symptoms of dyspepsia were evaluated with a study-specific questionnaire. Switching to Aspirin Cardio (group 1) was on discretion of the physician in charge based on the history of gastrointestinal (GI) complications or significant manifestations of dyspepsia.

RESULTS

The efficacy in prevention of cardiovascular events was similar in all groups. No "major" or "minor, clinically significant" bleeding (ISTH) were observed. Proportions of patients with "minor" bleeding were similar in all groups with a tendency towards their decrease under the Aspirin Cardio treatment. After switching to Aspirin Cardio, positive changes in severity of GI symptoms by results of the questionnaire: a significant improvement of compliance by the treatment satisfaction index in group 1 and 2; and a 1.7 time decrease in the proportion of ASA-noncompliant patients were observed. According to the results of ROC analysis an average GI symptom score ≥3 predicted an improvement of compliance in case of switching to Aspirin Cardio with a diagnostic sensitivity of 72.3% and specificity of 51.1% (р=0.012) as well as alleviation of GI symptoms (sensitivity, 74.5%; specificity, 63.8%, р=0.001).

CONCLUSIONS

Different dosage forms of ASA are characterized with similar efficacy in prevention of cardiovascular events and effects on the risk of bleeding. Aspirin Cardio showed a better tolerability due to a less effect on GI symptoms. It provided a better compliance to chronic treatment. This study confirmed advisability of using the proposed questionnaire to evaluate GI symptoms for specification of prediction and modification of therapy.

Safranal, a constituent of saffron, exerts gastro-protective effects against indomethacin-induced gastric ulcer

AIMS

Several natural products have been evaluated for management of gastric ulcer induced by non-steroidal anti-inflammatory drugs. Safranal, a plant-derived chemical, has a potent antioxidant and anti-inflammatory properties. The present study was aimed to evaluate possible gastro-protective effects of safranal against indomethacin-induced gastric ulcer in rats. Lansoprazole (a proton pump inhibitor) was used as a reference drug.

MATERIALS AND METHODS

Thirty rats were divided into five groups. Groups 1 and 2 received vehicle. Groups 3, 4 and 5 treated with 0.063, 0.25 and 1 mg/kg safranal. Group 6 received 30 mg/kg lansoprazole. All groups except of group 1 received indomethacin (50 mg/kg) ingestion. Six hours later, animals were euthanized and their stomachs were removed. Gastric contents volume and pH were measured. Gastric ulcer area and protective index were evaluated using image J software. Histological changes were evaluated by light microscope. Malondialdehyde (MDA) level, superoxide dismutase (SOD) activity, total antioxidant capacity (TAC) content, tumor necrosis factor-alpha (TNF-α) and Caspase-3 levels were determined in the gastric tissue.

KEY FINDINGS

Safranal and lansoprazole normalized gastric volume and pH, reduced gastric ulcer area and produced gastric protection. Indomethacin-induced histological changes and tissue biochemical alterations were ameliorated by the above-mentioned treatments.

SIGNIFICANCE

The results of the present study suggest the involvement of anti-secretory, anti-oxidant, anti-inflammatory and anti-apoptotic mechanisms in gastro-protective effect of safranal. In addition, gastro-protective effect of safranal was comparable to lansoprazole.

Chemical characterization and evaluation of gastric antiulcer properties of the hydroethanolic extract of the stem bark of Virola elongata (Benth.) Warb

ETHNOPHARMACOLOGICAL RELEVANCE

Virola elongata is a tree species belonging to the Myristicaceae family, distributed in the North and Midwest regions of Brazil, in the phytogeographic domain of the Amazon. The aqueous infusion or the hydroethanolic macerate of the stem bark of V. elongata are used in Brazilian and Ecuadorian indigenous folk medicine for several ethnopharmacological purposes, principally, in the treatment of stomach pain, indigestions, and gastric ulcers. This study was aimed to investigate the gastroprotective activity of this plant in order to support its popular use with scientific evidence.

MATERIALS AND METHODS

The stem bark hydroethanolic extract of the plant (HEVe) was prepared by maceration. Its qualitative and quantitative phytochemical constituents were investigated by classical colorimetric techniques, HPLC, and electrospray ionization-multiple stage fragmentation (ESI-MSⁿ). The gastroprotective and antiulcer activity of HEVe at doses of 100, 300 and 900 mg/kg p.o. were tested using three acute (acidified ethanol, piroxicam, and in-water-restrain stress), and one chronic (acetic acid) animal ulcer models. The probable mode of action of the HEVe was evaluated by analyzing gastric acid secretion, mucus content, nitric oxide effect, and its antioxidant properties (on catalase, myeloperoxidase, and GSH content) in experimental rodents. The direct extract's activity on the growth of Helicobacter pylori was also investigated.

RESULTS

Total phenolic content in the HEVe was of 146.20 ± 1.07 mg, being flavonoids about 50% (71.79 ± 0.70 mg) of it. Comparative HPLC fingerprint analysis revealed the presence of known phenolic antiulcer compounds, such as gallic acid, catechin, and rutin. Also, methanol/water fractionation and ESI-MSⁿ analysis of the HEVe reveals the presence of quinic acid, 3,3',4-trihydroxystilbene, juruenolid D, one catechin dimer, one C-glycosyl flavonoid, one polyketide and two neolignans as the major components of the extract. The HEVe attenuated gastric ulceration in all the different models of acute gastric ulcer, by enhancing gastroprotection through its antioxidant properties in vivo, and reducing also considerably the gastric secretion and total acidity. The HEVe also presented healing properties against the induced chronic ulceration process. On the other hand, the HEVe did not exhibit direct activity against H. pylori.

CONCLUSION

The HEVe exhibited significant gastroprotective/antiulcer effects and contain a relative high proportion of phenolic compounds, especially flavonoids, that could likely account, at least in part, for its pharmacological properties. The results justify its traditional usage and provided scientific evidence for its potential as a new herbal medicine to treat gastric ulcers.

International Consensus on Guiding Recommendations for Management of Patients with Nonsteroidal Antiinflammatory Drugs Induced Gastropathy-ICON-G

Introduction

Nonsteroidal anti-inflammatory drugs (NSAIDs), one of the most commonly used medications worldwide, are frequently associated with gastrointestinal adverse events. Primary care physicians often face the challenge of achieving adequate pain relief with NSAIDs, while keeping their adverse events to a minimum. This is especially true when long-term use of NSAIDs is required such as in patients with osteoarthritis and rheumatoid arthritis. To help primary care physicians deal with such challenges more effectively, a panel of expert gastroenterologists came together with the aim of developing practice recommendations.

Methods

A modified ‘Delphi’ process was used to reach consensus and develop practice recommendations. Twelve gastroenterologists from nine countries provided their expert inputs to formulate the recommendations. These recommendations were carefully developed taking into account existing literature, current practices, and expert opinion of the panelists.

Results

The expert panel developed a total of fifteen practice recommendations. Following are the key recommendations: NSAIDs should be prescribed only when necessary; before prescribing NSAIDs, associated modifiable and non-modifiable risk factors should be considered; H. pylori infection should be considered and treated before initiating NSAIDs; patients should be properly educated regarding NSAIDs use; patients who need to be on long-term NSAIDs should be prescribed a gastroprotective agent, preferably a proton pump inhibitor and these patients should be closely monitored for any untoward adverse events.

Conclusion/clinical significance

These practice recommendations will serve as an important tool for primary care physicians and will guide them in making appropriate therapeutic choices for their patients.

How to cite this article: Hunt R, Lazebnik LB, Marakhouski YC, Manuc M, Ramesh GN, Aye KS, Bordin DS, Bakulina NV, Iskakov BS, Khamraev AA, Stepanov YM, Ally R, Garg A. International Consensus on Guiding Recommendations for Management of Patients with Nonsteroidal Anti-inflammatory Drugs Induced Gastropathy-ICON-G. Euroasian J Hepatogastroenterol, 2018;8(2):148-160.

The relatively selective cyclooxygenase-2 inhibitor nimesulide: What's going on?

Nimesulide is a relatively selective cyclooxygenase (COX)-2 inhibitor, non-steroidal anti-inflammatory drug; it has been discovered in 1971 and firstly commercialized in Italy in 1985. There is much evidence that the pharmacological profile of nimesulide is peculiar and not shared with the other COX-2 selective inhibitors, suggesting that other molecular mechanisms besides inhibition of COX-2 derived prostaglandins are involved. Similarly, experimental data suggest that the gastrointestinal safety of nimesulide cannot be ascribed only to a COX-1 sparing effect. On the inflammatory process, the efficacy of nimesulide is dependent upon a wide spectrum of actions, due to the combination of effects on immune and non-immune cells. Early data demonstrated a central role for cyclic AMP (cAMP) in the anti-inflammatory effect of nimesulide; more recently, we have shown the involvement of the pathway ecto-5'-nucleotidase/adenosine A_2A receptor. To date, the molecular mechanism(s) that confers uniqueness to nimesulide have not yet been defined. To go inside the mechanism of action of an existing drug, such as nimesulide, would be helpful to refine its therapeutic use but also to identify new targets for novel therapeutic anti-inflammatory approach. Here, we focus on accumulated evidence for a peculiar pharmacological profile of nimesulide.

Effects of dipyrone on the digestive tract

Dipyrone (metamizole), acting through its main metabolites 4-methyl-amino-antipyrine and 4-amino-antipyrine, has established analgesic, antipyretic, and spasmolytic pharmacological effects, which are mediated by poorly known mechanisms. In rats, intravenously administered dipyrone delays gastric emptying (GE) of liquids with the participation of capsaicin-sensitive afferent fibers. This effect seems to be mediated by norepinephrine originating from the sympathetic nervous system but not from the superior celiac-mesenteric ganglion complex, which activates β2-adrenoceptors. In rats, in contrast to nonselective non-hormonal anti-inflammatory drugs, dipyrone protects the gastric mucosa attenuating the development of gastric ulcers induced by a number of agents. Clinically, it has been demonstrated that dipyrone is effective in the control of colic-like abdominal pain originating from the biliary and intestinal tracts. Since studies in humans and animals have demonstrated the presence of β2-adrenoceptors in biliary tract smooth muscle and β2-adrenoceptor activation has been shown to occur in dipyrone-induced delayed GE, it is likely that this kind of receptors may participate in the reduction of smooth muscle spasm of the sphincter of Oddi induced by dipyrone. There is no evidence that dipyrone may interfere with small bowel and colon motility, and the clinical results of its therapeutic use in intestinal colic appear to be due to its analgesic effect.

Antioxidative and Anti-Inflammatory Effects of Water Extract of Acrostichum aureum Linn. against Ethanol-Induced Gastric Ulcer in Rats

Acrostichum aureum Linn., a medicinal pteridophyte growing in mangrove forests and coastal regions of tropical and subtropical areas worldwide, has been proved to possess various biological effects. However, the protective effect of Acrostichum aureum Linn. against gastric ulcer still remains unidentified. Therefore, the gastroprotective effect of the water extract of Acrostichum aureum Linn. (WEAC) was investigated in ethanol-induced gastric injury model. According to our results, pretreatment with WEAC (100, 200, and 400 mg/kg) could dramatically decrease the ulcer areas and ameliorate the pathological damage induced by alcohol in rat's gastric tissues. In addition, WEAC administration prevented the stomach from oxidative damage via markedly increasing the levels of glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and decreasing the malondialdehyde (MDA). Besides, WEAC pretreatment alleviated inflammatory infiltration by reducing the secretion of proinflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) as well as decreasing the protein expressions of phosphorylation of IκBα and p65. Taken together, WEAC exerted potential therapeutic efficacy for gastric ulceration, and this may be involved in the suppression of oxidative stress and inflammatory response.

Effects and possible mechanisms of Alpinia officinarum ethanol extract on indomethacin-induced gastric injury in rats

CONTEXT

Alpinia officinarum Hance (Zingiberoside) has a long history in treating gastrointestinal diseases, but its mechanisms of action are not yet known.

OBJECTIVE

To investigate the effects and underlying mechanisms of the ethanol extract of A. officinarum rhizomes in an indomethacin-induced gastric injury rat model.

MATERIAL AND METHODS

Indomethacin (0.3 g/kg) was orally administered to Sprague-Dawley rats to induce gastric damage; after 7 h, the rats were treated with 0.03, 0.09, or 0.18 g/kg of the plant extract, galangin (0.2 g/kg), or bismuth potassium citrate (0.08 g/kg), once a day for 6 days. Rats in the control group received an equivalent volume of vehicle solution for 6 days. Gastric damage was evaluated by gross ulcer and histological indexes. Cyclooxygenase and non-cyclooxygenase pathway proteins were quantified by western blotting and ELISA.

RESULTS

Alpinia officinarum extract ameliorated gastric injury in a dose-dependent manner, and 0.18 g/kg dose exhibited the best performance by reducing the gross ulcer (from 20.23 ± 1.38 to 1.66 ± 0.37) and histological (from 4.67 ± 1.03 to 0.33 ± 0.51) indexes, decreasing serum TNF-α level (14.17%), increasing serum VEGF level (1.58 times), increasing cyclooxygenase-1 level (1.25 times, p <  0.001) in the gastric mucosa, and reversing indomethacin-induced changes in the expression of non-cyclooxygenase pathway proteins (p <  0.05). Galangin was less effective as an antiulcer agent than the whole extract, indicating that other components also contributed to the protective effect.

CONCLUSIONS

Alpinia officinarum extract and galangin exert antiulcer effects through cyclooxygenase and non-cyclooxygenase pathways validating use of galangin as a treatment for gastric damage.

Regulation of mPGES-1 composition and cell growth via the MAPK signaling pathway in jurkat cells

Previous studies have suggested that microsomal prostaglandin E synthase-1 (mPGES-1) is highly expressed and closely associated with mitogen-activated protein kinase (MAPK) signaling pathways in various types of malignant cells. However, their expression patterns and function with respect to T-cell acute lymphoblastic leukemia (T-ALL) remain largely unknown. The present study investigated whether mPGES-1 served a crucial role in T-ALL and aimed to identify interactions between mPGES-1 and the MAPK signaling pathway in T-ALL. The results indicated that mPGES-1 overexpression in T-ALL jurkat cells was significantly decreased by RNA silencing. Decreasing mPGES-1 on a consistent basis may inhibit cell proliferation, induce apoptosis and arrest the cell cycle in T-ALL jurkat cells. Microarray and western blot analyses revealed that c-Jun N-terminal kinase served a role in the mPGES-1/prostaglandin E2/EP4/MAPK positive feedback loops. In addition, P38 and extracellular signal-regulated kinase 1/2 exhibited negative feedback effects on mPGES-1. In conclusion, the results suggested that cross-talk between mPGES-1 and the MAPK signaling pathway was very complex. Therefore, the combined regulation of mPGES-1 and the MAPK signaling pathway may be developed into a new candidate therapy for T-ALL in the future.

Network pharmacology-based identification of protective mechanism of Panax Notoginseng Saponins on aspirin induced gastrointestinal injury

BACKGROUND & AIMS

Aspirin is the first line therapy for cardiovascular and cerebrovascular diseases and is widely used. However aspirin-induced gastrointestinal injury is one of its most common side effect which limits long-term use. Panax Notoginseng Saponins(PNS) which is also used to prevent thrombus may alleviate this side effect according to previous clinical evidences. Owing to the complexity of drug combination, the protective mechanism of PNS on aspirin-induced gastrointestinal injury remains unclear. Therefore, a network pharmacology-based strategy was proposed in this study to address this problem.

METHODS

A network pharmacology approach comprising multiple components, candidate targets of each component, known therapeutic targets, network analysis has been used in this study. Also, we establish aspirin-induced gastrointestinal injury model by the oral administration of aspirin (0.5 g/kg body weight) to verify the predicted targets from network pharmacology. All rats was randomly allocated to control groups (n = 6),aspirin groups (n = 6)and aspirin + PNS groups (n = 6) and conducted H&E staining and ELISA for VEGFA.

RESULTS

The comprehensive systematic approach was successfully to identify 5 compounds and 154 candidate targets in PNS and 479 candidate targets in aspirin. After network establishment and analysis, 27 potential targets hit by PNS, aspirin and 6 kind of gastrointestinal diseases were found. The experiments results indicated that aspirin group has visible inflammation and lesions while aspirin + PNS group have not. The higher expression of VEGFA in aspirin + PNS group verified the predicted potential protective targets of PNS.

CONCLUSIONS

PNS may have protective function for aspirin-induced gastrointestinal injury through increasing VEGFA expression. Network pharmacology strategy may provide a forceful tool for exploring the mechanism of herb medicine and discovering novel bioactive ingredients.

Acid and the basis for cellular plasticity and reprogramming in gastric repair and cancer

Subjected to countless daily injuries, the stomach still functions as a remarkably efficient digestive organ and microbial filter. In this Review, we follow the lead of the earliest gastroenterologists who were fascinated by the antiseptic and digestive powers of gastric secretions. We propose that it is easiest to understand how the stomach responds to injury by stressing the central role of the most important gastric secretion, acid. The stomach follows two basic patterns of adaptation. The superficial response is a pattern whereby the surface epithelial cells migrate and rapidly proliferate to repair erosions induced by acid or other irritants. The stomach can also adapt through a glandular response when the source of acid is lost or compromised (that is, the process of oxyntic atrophy). We primarily review the mechanisms governing the glandular response, which is characterized by a metaplastic change in cellular differentiation known as spasmolytic polypeptide-expressing metaplasia (SPEM). We propose that the stomach, like other organs, exhibits marked cellular plasticity: the glandular response involves reprogramming mature cells to serve as auxiliary stem cells that replace lost cells. Unfortunately, such plasticity might mean that the gastric epithelium undergoes cycles of differentiation and de-differentiation that increase the risk of accumulating cancer-predisposing mutations.

Endoscopic comparison of gastroduodenal injury with over-the-counter doses of new fast-dissolving ibuprofen and paracetamol formulations: a randomized, placebo-controlled, 4-way crossover clinical trial

Background

While gastrointestinal (GI) effects of standard ibuprofen and N-acetyl-p-aminophenol (APAP) have been reported, upper GI injury following treatment with fast-dissolving (FD) formulations of these analgesics has not been investigated. We evaluated upper GI effects of over-the-counter doses of 2 FD ibuprofen products and 1 FD-APAP product.

Methods

In a randomized, placebo-controlled, endoscopist-blinded, 4-way crossover study, 28 healthy subjects received FD ibuprofen 2×200 mg liquid capsules 3 times daily (TID), ibuprofen 2×200 mg tablets TID, FD-APAP 2×500 mg tablets 4 times daily (QID), and placebo 2×500 mg tablets QID for 7 days. The primary end point was gastric mucosal damage assessed by endoscopy using the Lanza scale: 0=normal stomach or proximal duodenum, 1=mucosal hemorrhages only, 2=1 or 2 erosions, 3=numerous (3-10) erosions, and 4=large number of erosions (>10) or ulcer. Secondary end points included duodenal mucosal damage (Lanza scale); gastroduodenal mucosal injury, classified as present (gastric and/or duodenal endoscopy score ≥2) or absent (gastric and/or duodenal endoscopy score <2); and number of hemorrhages, erosions, and ulcers counted separately in the stomach and duodenum.

Results

Significantly greater gastric mucosal injury was observed after treatment with both ibuprofen products vs FD-APAP (p<0.0001 and p=0.0095, respectively). FD-APAP showed no difference from placebo (p=0.4794). The odds of having an incidence of gastroduodenal mucosal injury were over 6 times greater from FD ibuprofen liquid capsule treatment (odds ratio [OR]=6.19, 95% confidence interval [CI]: 1.60, 23.97) and over 3 times greater from ibuprofen tablet treatment (OR=3.19, 95% CI: 0.8, 12.74) vs FD-APAP.

Conclusion

Treatment with 2 ibuprofen products was associated with significant gastric mucosal injury. Of the 4 treatments studied, FD ibuprofen liquid capsules had the highest risk of incidence of gastroduodenal mucosal injury. Treatment with FD-APAP did not induce any clinically or statistically significant gastroduodenal mucosal injury.

Panax quinquefolius saponins combined with dual antiplatelet drug therapy alleviate gastric mucosal injury and thrombogenesis through the COX/PG pathway in a rat model of acute myocardial infarction

Objectives

Previous studies have found that Panax quinquefolius saponins (PQS) combined with dual antiplatelet therapy (DAPT) of aspirin and clopidogrel enhances antithrombotic effects while reducing gastric mucosal injury induced by DAPT. We investigated the effects of the combined drug therapy (PQS+DAPT) through the COX/PG pathways.

Methods

Acute myocardial infarction (AMI) was induced in Wistar rats by ligation of the left anterior descending (LAD) coronary artery, and the animals were randomly divided into Model, DAPT, and PQS+DAPT groups. Rats in the sham group did not undergo artery ligation. They were intragastrically treated for 14 days. Myocardial infarct size; myocardial pathology; platelet aggregation rate, CD62p activation, concentrations of thromboxane B₂ (TXB₂), 6-keto-PGF1α, tissue plasminogen activator (t-PA), and plasminogen activator inhibitor (PAI), the TXB₂/6-keto-PGF1α ratio were measured. The ultrastructure of the gastric mucosa was observed by scanning electron microscopy. The expression of PGE₂ and 6-keto-PGF1α in gastric mucosa was measured by radioimmunoassay, and levels of COX-1, COX-2, and VEGF in gastric mucosa were assessed using immunohistochemistry.

Results

The addition of Panax quinquefolius saponins (PQS+DAPT) to standard DAPT therapy significantly decreased the myocardial infarct area, degree of myocardial lesions, TXB₂ and PAI levels, and the TXB₂/6-keto-PGF1α ratio, while increasing 6-keto-PGF1α and t-PA levels and reducing the degree of gastric mucosal injury. Expression of PGE₂, 6-keto-PGF1α, COX-2, and VEGF in the gastric mucosa was upregulated in the PQS+DAPT group compared with the standard DAPT group.

Conclusion

PQS increases the degree of DAPT inhibition of myocardial necrosis and antiplatelet effects in AMI rats, as well as reducing damage to the gastric mucosa caused by DAPT. The mechanism may be related to inhibition of TXB₂ and PAI activity and elevation of 6-keto-PGF1α and t-PA levels in blood, and may be associated with upregulated expression of COX-2, PGE₂, PGI₂, and VEGF in gastric tissue.

Protective role of β-patchoulene from Pogostemon cablin against indomethacin-induced gastric ulcer in rats: Involvement of anti-inflammation and angiogenesis

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAIDs) are most widely used as effective anti-inflammatory agents. However, their clinical application brings about inevasible gastrointestinal side effects. Pogostemon cablin is a traditional herbal medicine used for the treatment of gastrointestinal diseases in China. One of its representative components, the tricyclic triterpenoid β-patchoulone (β-PAE) has demonstrated great anti-inflammatory activity and gastroprotective effect against ethanol-induced gastric injury, but its protective effect against gastric ulcer induced by indomethacin is still unknown.

PURPOSE

To assess the protective effect of β-PAE against ulcer produced by indomethacin and reveal the underlying pharmacological mechanism.

STUDY DESIGN

We used an indomethacin-induced gastric ulcer model of rats in vivo.

METHODS

Gastroprotective activity of β-PAE (10, 20, 40 mg/kg, i.g.) was estimated via indomethacin-induced gastric ulcer model in rats. Histopathological and histochemical assessment of ulcerated tissues were performed. Protein and mRNA expression were determined by Elisa, Western blotting and qRT-PCR.

RESULTS

β-PAE could inhibit ulcer formation. Histopathological and histochemical assessment macroscopically demonstrated that β-PAE alleviates indomethacin-induced gastric ulceration in dose-dependent manner. After administration of β-PAE, elevated tumor necrosis factor -α level was significantly decreased and the phosphorylation of JNK and IκB was markedly inhibited. β-PAE suppressed the levels of E-selectin, P-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule and monocyte chemoattractant protein 1, as well as myeloperoxidase. Meanwhile, β-PAE increased cyclooxygenase enzyme activities (COX-1 and COX-2) to enhance the production of prostaglandin E₂. Proangiogenic protein, vascular endothelial growth factor and its receptor fms-like tyrosine kinase-1 mRNA expression were promoted while anti-angiogenic protein, endostatin-1 and its receptor ETAR mRNA expression were decreased.

CONCLUSION

β-PAE may provide gastroprotection in indomethacin-induced gastric ulcer in rats by reducing inflammatory response and improving angiogenesis.

Hydroalcoholic extract from bark of Persea major (Meisn.) L.E. Kopp (Lauraceae) exerts antiulcer effects in rodents by the strengthening of the gastric protective factors

ETHOPHARMACOLOGICAL RELEVANCE

The Persea major (Meisn.) L.E. Kopp (Lauraceae) (botanical synonym: Persea pyrifolia (D. Don) Spreng, Persea pyrifolia Nees and Mart., Persea cordata var. major (Meisn.) Mez and Persea willdenovii Kosterm) is a medicinal plant native in the south of Brazil, where is popularly known as Pau de Andrade, Maçaranduba or Abacate-do-Mato. Its barks are commonly used to prepare an infusion which is administered orally or topically to treat ulcers and wounds, respectively. Thus, this study has been undertaken to contribute to the validation of the popular use of P. major to treat of ulcerative disorders from gastrointestinal system, using different experimental models in rodents.

MATERIAL AND METHODS

Firstly, ultra-performance liquid chromatography coupled to a mass spectrophotometer has been performed. Next, the potential gastroprotective of hydroalcoholic extract of P. major barks (HEPM) (30-300mg/kg) has been evaluated in ulcer models acute as: ethanol, ethanol/HCl and indomethacin-induced ulcer. The extract (300mg/kg) has been also tested in acetic acid-induced chronic ulcer model. Histological, toxicological, histochemical, oxidative stress and gastric secretion parameters were analyzed.

RESULTS

The main compounds found in HEPM were polyphenols as condensed tannins, flavonoids heterosides derivatives from quercetin and kaempferol. HEPM (300mg/kg, p.o) prevented gastric lesions induced by ethanol or indomethacin in rats by 58.98% and 97.48%, respectively, compared to vehicle group (148.00±14.83mm² and 12.07±1.61mm², respectively). In acetic acid-induced chronic ulcer model the HEPM (300mg/kg, p.o) reduced the ulcer are by 40.58%, compared to vehicle group (127.90±12.04mm²). The healing effect was confirmed histologically, by an increase in mucin content and by the reduction in oxidative and inflammatory parameters at the ulcer site. Neither significant effect on gastric acid secretion nor toxicological effects and cytotoxicity were provoked by administration of HEPM.

CONCLUSIONS

The results allows to conclude that HEPM exerts gastroprotective and gastric cicatrizing effects favoring on protective defenses, but not possess antisecretory effect in contrast to the current antiulcer therapy, besides the extract present good tolerability and absence of cytotoxicity. Moreover, the results presented here contribute to the validation to the popular use of the P. major in the treatment of gastric ulcer.

Gastroprotective and Antiulcer Effects of Celastrus paniculatus Seed Oil Against Several Gastric Ulcer Models in Rats

Peptic ulcer is a recurrent chronic illness and has become almost a hallmark of the so-called civilized life. In folk medicine, the Celastrus paniculatus plant has been used for the prevention and treatment of various diseases and gastrointestinal disturbances, including dyspepsia and stomach ulcers. The aim of this study is to evaluate the gastroprotective and antiulcer effects of Celastrus paniculatus seed oil (CPO) against several gastric ulcer models in rats. The gastroprotective and antiulcer effects of CPO were evaluated using pylorus-ligated ulcer ethanol- and indomethacin-induced ulcers using rantidine (40 mg/kg per os [PO]) as standard. Gastrointestinal motility was determined by gastric emptying time and gastrointestinal transit ratio. The results of the pharmacological studies of CPO (200 mg/kg, 400 mg/kg) demonstrated effective gastroprotection against ethanol- and indomethacin-induced ulcer models. In pylorus-ligated rats, the seed oil showed gastroprotective activity by decreasing total gastric juice volume and gastric acidity while increasing the gastric pH. The gastroprotection against ethanol and indomethacin is partially attributed to effective inhibition of proinflammatory cytokines, TNF-α and IL-6, and increase in the levels of IL-10. Treatment with CPO in ethanol-induced ulcer rats significantly (p < .05) decreased MDA (malondialdehyde) levels, which were accompanied by an increase in the activities of SOD (superoxide dismutase) and catalase. CPO reduced the rate of gastric emptying but had no effect on gastrointestinal transit. The present findings indicate that CPO has potent gastroprotective effects and support the folkloric usage of the seed oil to treat various gastrointestinal disturbances.

Genistein-attenuated Gastric Injury on Indomethacin-induced Gastropathy in Rats

Objectives:

To investigates the mucoprotective effect of genistein on gastric injury in rats with indomethacin (IMN)-induced gastropathy.

Methods:

Male Sprague-Dawley rats were randomly divided into three groups. Group 1 (control; n = 6) was given distilled water (DW). Group 2 (IMN; n = 6) was given indomethacin (IMN) 150 mg/kg dissolved in 5% sodium bicarbonate (NaHCO₃^-) 1 mL/rat via intragastric tube at time 0 and 4 h. Group 3 (genistein; n = 6) was given genistein 100 mg/kg dissolved in 0.1% dimethyl sulfoxide (DMSO) plus IMN 150 mg/kg at time described as group 2. Four hours after the second dose, the stomach was removed to examine iNOS western blot expression, malondialdehyde (MDA), and histopathologic examination. Serum was collected to determine TNF-alpha and prostaglandin E₂ (PGE₂) levels using ELISA technique.

Results:

Tissue MDA and serum TNF-alpha were significantly increased in the IMN group, as compared to the control group (9.70 ± 0.40 vs. 1.56 ± 0.14 nmol/mg protein, P = 0.000; 210.28 ± 0.98 vs. 126.4 ± 0.13 pg/mL, P = 0.000, respectively) and decreased in the genistein group when compared to the IMN group (2.87 ± 0.37 vs. 9.70 ± 0.40 nmol/mg protein, P = 0.000; 156.59 ± 0.10 vs. 210.28 ± 0.98 pg/mL, P = 0.000, respectively). Serum PGE₂ level in IMN group was decreased significantly compared with control group (152.83 ± 0.10 vs. 303.33 ± 2.16 pg/mL, P = 0.000) and increased in the genistein group compared to the IMN group (247.65 ± 0.01 vs. 152.83 ± 0.10 pg/mL, P = 0.000). Expression of tissue iNOS was increased in the IMN group and improved in genistein groups. Most of the rats in the IMN group developed moderate to severe gastric erosion and ulcers. Gastric erosions and neutrophil infiltration score were significantly decreased in the genistein group.

Conclusions:

Genistein attenuated IMN-induced gastropathy in rats by reducing inflammation, decreasing oxidative stress, restoring mucoprotective function, and improving gastric histopathology.

SUMMARY

This is an experimental study of the effect of NSAIDs in gastropathy. This study demonstrated the efficacy of genistein in treatment of NSAIDs-induced gastropathy. Genistein efficacy is reflected in the attenuation of histological alterations, with improvement in key biological parameters involved in the pathogenesis of NSAIDs gastropathy.

Abbreviations used: NSAIDs: Non-steroidal anti-inflammatory drugs; IMN: Indomethacin; COX: Cyclooxygenase; TNF: Tumor necrosis factor; ICAM: Intercellular adhesion molecule; iNOS: Inducible nitric oxide synthase; MDA: Malondialdehyde; CINC: Cytokine-induced neutrophil chemoattractant.

MAGL inhibition modulates gastric secretion and motility following NSAID exposure in mice

Non-steroidal anti-inflammatory drugs (NSAIDs) are common analgesic drugs that also cause well-known, negative gastrointestinal (GI) side effects. The physiological mechanism(s) of NSAID-induced GI damage are unclear and are likely due to multiple causes. The most studied contributing mechanisms are increased gastric acid secretion and increased gastric motility. The present study was designed to determine which ulcerogenic effects of the NSAID diclofenac sodium are reversed by blocking the endocannabinoid catabolic enzyme monoacylglycerol lipase (MAGL). Both male and female mice were used to identify possible sex differences. We hypothesized that the MAGL inhibitor JZL184 would attenuate diclofenac-induced increases in both gastric acid secretion and gastric motility. Diclofenac dose-dependently induced gastric hemorrhages to a similar extent in both male and female mice. Gastric hemorrhage severity significantly correlated with gastric levels of myeloperoxidase, an objective measure of neutrophil infiltration. Similarly, JZL184 reduced gastric acidity, in controls as well as mice treated with pentagastrin, which stimulates gastric acid release. As hypothesized, JZL184 decreased gastric motility. Surprisingly, diclofenac also slowed gastric emptying, indicating that diclofenac-induced ulcers most likely occur through increased gastric acid secretion, and not increased gastric motility, as measured in the present study. Thus, MAGL inhibition may proffer gastroprotection through modulating the secretory pathway of gastric hemorrhage. These data underscore the importance of sampling multiple time points and using both sexes in research, in addition to multiple mechanistic targets, and contribute to the basic understanding of NSAID-induced gastric inflammation.

N-acetylcysteine a possible protector against indomethacin-induced peptic ulcer: crosstalk between antioxidant, anti-inflammatory, and antiapoptotic mechanisms

This study investigated the gastroprotective effects of N-acetylcysteine (NAC) against indomethacin-induced gastric ulcer in rats. Ulceration was induced by a single oral administration of indomethacin (30 mg/kg). 50 male albino rats were allocated into 5 equal groups: control group received normal saline orally, indomethacin group rats received normal saline orally for 5 days and indomethacin (50 mg/kg) on the last day, ranitidine group received ranitidine (reference drug) orally for 5 days (50 mg/kg) before receiving indomethacin (50 mg/kg) on the last day, and NAC groups received NAC orally at 300 and 500 mg/kg, respectively, for 5 days before receiving indomethacin (50 mg/kg) on the last day. Gastric tissue interleukin-1β (IL-1β), interferon-γ (IFN-γ), and caspase-3 levels were immunoassayed. Total thiol (T-SH), myeloperoxidase (MPO), and glucose-6-phosphate dehydrogenase (G6PD) were determined by spectrophotometry. Cytokine-induced neutrophil chemoattractant 2α (CINC-2α) gene expression was evaluated in addition to Bcl-2 immunohistochemistry. Pretreatment with NAC improved the inflammatory, apoptotic, and redox status in a dose-dependent manner particularly in NAC 500 mg/kg pretreated group. These results show a role for NAC in improving indomethacin-induced gastric ulceration via antioxidative, antiapoptotic, and anti-inflammatory interactive mechanisms.

Neuroprotective effect of 2-hydroxy arachidonic acid in a rat model of transient middle cerebral artery occlusion

Stroke modifies the composition of cell membranes by eliciting the breakdown of membrane phospholipids whose products, such as arachidonic acid (AA), are released in the cytosol. The action of enzymes such as cyclooxygenases on AA leads to inflammatory stimuli and increases the cell oxidative stress. We report here the neuroprotective effect of 2-hydroxyarachidonic acid (2OAA), a cyclooxygenase inhibitor derived from AA, as a promising neuroprotective therapy against stroke. The effect of a single dose of 2OAA, administered intragastrically 1h after the ischaemic insult, in a rat model of transient middle cerebral artery occlusion (tMCAO) was tested after 24h of reperfusion. Infarct volume was measured by TTC method to evaluate the neuroprotective effect. Levels of phospholipids and neutral lipids were measured by thin-layer chromatography. The expression of cPLA2 and sPLA2 phospholipases responsible for the cleavage of membrane phospholipids, as well as the expression of antioxidant enzymes, was measured by qPCR. Lipid peroxidation was measured as the concentration of malondialdehyde and 4-hydroxynonenal. The treatment with 2OAA reduced the infarct volume and prevented ischaemia-induced increases in transcription levels of free fatty acid (FFAs), as well as in both phospholipases A2 (cPLA2 and sPLA2). The lipid peroxidation and the transcription levels of antioxidant enzymes induced by ischaemia were also decreased by this treatment. We conclude that 2OAA treatment results in a strong neuroprotective effect that seems to rely on a decrease in PLA2 transcriptional activity. This would reduce their action on the membrane phospholipids reducing reactive oxygen and nitrogen species generated by FFAs. Based on the transcriptional activity of the antioxidant enzymes, we conclude that the treatment prevents oxidative stress rather than promoting the antioxidant response. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá.

Gastroprotective effects of hydroethanolic root extract of Arrabidaea brachypoda: Evidences of cytoprotection and isolation of unusual glycosylated polyphenols

The hydroethanolic root extract of Arrabidaea brachypoda, from Bignoniaceae family, a Brazilian medicinal plant, demonstrated significant in vivo gastroprotective effects using different in vivo assays. The activity was evaluated in several models of experimental gastric ulcer in rats (absolute ethanol, glutathione depletion, nitric oxide depletion, non-steroidal anti-inflammatory drugs, pylorus ligation and acetic acid). Using 300 mg/kg (p.o.) the extract significantly reduced gastric injury in all models. In depth phytochemical investigation of this extract led to the isolation of two previously undescribed phenylethanoid glycosides derivatives and seven unusual glycosylated dimeric flavonoids. The structures were elucidated using UV, NMR and HRMS analysis. Absolute configuration of the dimeric flavonoids was performed by electronic circular dichroism (ECD) spectroscopy.

Investigational drugs targeting the prostaglandin E2 signaling pathway for the treatment of inflammatory pain

Non-steroidal anti-inflammatory drugs (NSAID) are the most commonly used drugs for the treatment of pain, inflammation and fever. Although they are effective for a huge number of users, their analgesic properties are not sufficient for several patients and the occurrence of side effects still constitutes a big challenge during long term therapy. Areas covered: This review gives an overview about the first and second generations of NSAIDs (COX1/2 non-selective, COX-2 selective), and their main side effects which gave still an urgent need for safer drugs and for the establishment of novel treatment strategies (improved safety, tolerability, patient convenience). The current developments of a possible third generation NSAID class comprise changes in the formulation of already approved drugs, combination therapies, dual cyclooxygenase-lipoxygenase inhibitors, NO- and H₂S-releasing NSAIDs, prostaglandin synthase inhibitors and EP receptor modulators, respectively. Literature search has been done with PubMed NCBI. Expert opinion: Currently, there is no newly developed drug that is superior to the already approved selective and non-selective NSAIDs. Several novel approaches show promising analgesic efficacy but side effects are still an important problem. Solutions might be constituted by combination therapies allowing administration of lower drug doses or by individualized therapies targeting molecules apart from COX, respectively.

The essential oil from the twigs of Cinnamomum cassia Presl alleviates pain and inflammation in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Cinnamomum cassia Presl (Lauraceae) can be found southern China and its bark is commonly used for centuries as ingredient in food and cosmetic industry. The twigs of Cinnamomum cassia Presl is popularly used in China to treat inflammatory processes, pain, menstrual disorders, hypertension, fever etc. The aim of this study is to evaluate the antinociceptive and anti-inflammatory properties of the essential oil (EO) from the twigs of Cinnamomum cassia Presl.

MATERIAL AND METHODS

The chemical characterization of the EO was performed by gas chromatography coupled with mass spectrometry (GC-MS). The EO doses of 15, 30, and 60mg/kg were employed in the biological assays. The antinociceptive effects of the EO were evaluated using the models of acetic acid-induced writhing, oxytocin-induced writhing, and formalin and complete Freund's adjuvant (CFA) -induced overt pain tests. we also investigated the effect of the EO in pain intensity to a mechanical stimulus (mechanical hyperalgesia) after carrageenan by using an electronic version of von Frey filaments. Evaluation of anti-inflammatory activity was based on paw edema induced by carrageenan (300µg/25µL/paw) in mice. The levels of cytokines, NO, and PGE2 in paw skin tissue were determined according to instructions. COX-2 and iNOS proteins in paw skin tissue were assessed by Western Blot.

RESULTS

The EO (15, 30, and 60mg/kg) reduced the number of abdominal writhings induced by acetic acid with inhibition of 38.0%, 55.4% and 58.7%, respectively. The EO (15, 30, and 60mg/kg) also reduced the number of abdominal writhings induced by oxytocin with inhibition of 27.3%, 51.7% and 69.0%, respectively. The EO significant inhibited the inflammatory (second phase: 10-30min) phase of the formalin-induced paw flinching and licking at the doses of 15, 30, and 60mg/kg. The EO at the tested doses of 15, 30, and 60mg/kg showed inhibited CFA-induced paw flinching and licking. The EO (15, 30, and 60mg/kg) also inhibited carrageenan-induced mechanical hyperalgesia and paw edema. It also decreased the levels of cytokines (TNF-α, and IL-1β), NO, and PGE2 in carrageenan-induced mice paw skin tissue. Moreover, Western blot analysis showed that COX-2 and iNOS expressions in paw skin tissue of mice were significantly reduced.

CONCLUSIONS

These results demonstrate that the antinociceptive and anti-inflammatory properties of the EO from the twigs of Cinnamomum cassia Presl, corroborating its use in folk medicine.

Novokinin inhibits gastric acid secretion and protects against alcohol-induced gastric injury in rats

Novokinin (Arg-Pro-Leu-Lys-Pro-Trp), a potent vasorelaxing and hypotensive peptide modified from ovokinin, exhibits highly selective affinity for the AT₂ receptor. However, its role in gastrointestinal functions is still not fully understood. In this study, we found that novokinin inhibited basal gastric acid secretion and protected gastric mucosa from alcohol-induced injury in a dose-related manner in rats after intracerebroventricular (i.c.v.) administration. Novokinin significantly decreased basal gastric acid output at the dose of 50 and 100 nmol/rat. The effect of novokinin on gastric acid secretion was reversed by central injection of PD 123319 (10 nmol/rat), an AT₂ receptor antagonist, and peripheral injection of indomethacin (10 mg/kg), an inhibitor of prostaglandin synthesis. Meanwhile, pre-treatment with novokinin at doses of 10, 50, and 100 nmol/rat significantly reduced the alcohol-induced gastric mucosal injury compared to the ulcer-control group, which was inhibited by indomethacin (10 mg/kg). The result showed a remarkable increase in the level of prostaglandin E2 (PGE₂), glutathione (GSH), and a decrease in malondialdehyde (MDA) after i.c.v. administration of novokinin. These findings suggest that the inhibitory effect of novokinin on gastric acid secretion is probably mediated via an AT₂ receptor-prostaglandins (PGs) pathway. The gastroprotective effect of novokinin might be attributed to the inhibition of acid secretion, the cytoprotection of PGs, and the antioxidant property.

Dual Alpha2C/5HT1A Receptor Agonist Allyphenyline Induces Gastroprotection and Inhibits Fundic and Colonic Contractility

BACKGROUND

Allyphenyline, a novel α2-adrenoceptor (AR) ligand, has been shown to selectively activate α2C-adrenoceptors (AR) and 5HT1A receptors, but also to behave as a neutral antagonist of α2A-ARs. We exploited this unique pharmacological profile to analyze the role of α2C-ARs and 5HT1A receptors in the regulation of gastric mucosal integrity and gastrointestinal motility.

METHODS

Gastric injury was induced by acidified ethanol in Wistar rats. Mucosal catalase and superoxide dismutase levels were measured by assay kits. The effect of allyphenyline on electrical field stimulation (EFS)-induced fundic and colonic contractions was determined in C57BL/6 mice.

RESULTS

Intracerebroventricularly injected allyphenyline (3 and 15 nmol/rat) dose dependently inhibited the development of mucosal damage, which was antagonized by ARC 239 (α2B/C-AR and 5HT1A receptor antagonist), (S)-WAY 100135 (selective 5HT1A receptor antagonist), and JP-1302 (selective α2C-AR antagonist). This protection was accompanied by significant elevation of mucosal catalase and superoxide dismutase levels. Allyphenyline (10(-9)-10(-5) M) also inhibited EFS-induced fundic contractions, which was antagonized by ARC 239 and (S)-WAY 100135, but not by JP-1302. Similar inhibition was observed in the colon; however, in this case only ARC 239 reduced this effect, while neither selective inhibition of α2C-ARs and 5HT1A receptors nor genetic deletion of α2A- and α2B-ARs influenced it.

CONCLUSIONS

Activation of both central α2C-ARs and 5HT1A receptors contributes to the gastroprotective action of allyphenyline in rats. Its inhibitory effect on fundic contractions is mediated by 5HT1A receptors, but neither α2-ARs nor 5HT1A receptors take part in its inhibitory effect on colonic contractility in mice.

Anti-inflammatory and antinociceptive activities of Croton urucurana Baillon bark

ETHNOPHARMACOLOGICAL RELEVANCE

Croton urucurana (Euphorbiaceae) is popularly used in Brazil to treat inflammatory processes, pain, and gastric ulcers.

AIM OF STUDY

To evaluate the anti-inflammatory and antinociceptive properties of the methanol extract from the bark of C. urucurana (MECu) in mice and identify its chemical constituents.

MATERIALS AND METHODS

The extract was characterized by UHPLC-DAD-ESI-Q-TOF-MS/MS. Extract doses of 25, 100, and 400mg/kg were employed in the biological assays. Evaluation of anti-inflammatory activity was based on paw edema and leukocyte recruitment into the peritoneal cavity of mice, both induced by carrageenan. Abdominal writhing caused by acetic acid and duration of formalin-induced paw-licking were the models employed to evaluate antinociceptive activity.

RESULTS

Ten compounds were identified in the extract: (+)-gallocatechin (1), procyanidin B3 (2), (+)-catechin (3), (-)-epicatechin (4), tembetarine (5), magnoflorine (6), taspine (7), methyl-3-oxo-12-epi-barbascoate (8), methyl-12-epi-barbascoate (9), and hardwickiic acid (10). This is the first report of compounds 2, 4, 6, 7, and 10 in C. urucurana and compound 5 in the genus Croton. In addition to inhibiting paw edema and leukocyte recruitment (particularly of polymorphonuclear cells) into the peritoneal cavity of mice, MECu reduced the number of abdominal writhings induced by acetic acid and the duration of formalin-induced paw licking.

CONCLUSIONS

The methanol extract of C. urucurana bark exhibited anti-inflammatory and antinociceptive properties, corroborating its use in folk medicine. These effects may be related to the presence of diterpenes, alkaloids, and flavonoids.

Protective effects of Weilikang decoction on gastric ulcers and possible mechanisms

Although Weilikang decoction (WLK) has been used for gastric ulcer (GU) therapy in a clinical setting with good curative effect for >20 years, the mechanism remains unclear. Several GU animal models, induced by ethanol, hydrochloric acid, aspirin, pylorus ligation, acetic acid and indomethacin, were used to investigate the gastroprotective effects of WLK decoction. Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME), indomethacin, and N-ethylmaleimide (NEM) were pretreated, respectively, to investigate the action mechanism. Real-time polymerase chain reaction and Western blot analysis methods were used to determine the effects of WLK on indomethacin-induced GUs. The WLK-administered groups (2.5, 1.25 and 0.625 g/kg) significantly reduced the GU areas induced by ethanol, hydrochloric acid and aspirin. Furthermore, the effects could be quenched by L-NAME and NEM, but not by indomethacin. The 2.5 and 1.25 g/kg WLK groups showed significantly decreased effects on GU areas induced by pylorus ligation and acetic acid. WLK treatment significantly decreased mRNA expression on cyclooxygenase (COX)-1, COX-2, interleukin-6, tumor necrosis factor α and inducible nitric oxide synthase (iNOS) mRNA, but showed no effect on endothelial nitric oxide synthase mRNA expression. Western blot analysis result showed that WLK-treated groups markedly downregulated COX-2 protein expression. The anti-ulcer potential of WLK can be primarily attributed to its regulatory effects on nitric oxide, sulfhydryl compounds, and reduction effect on mucosal expression of proinflammatory cytokines.

Safety and anti-ulcerogenic activity of a novel polyphenol-rich extract of clove buds (Syzygium aromaticum L)

Despite the various reports on the pharmacology of Clove bud [Syzygium aromaticum]-derived essential oil and its major component eugenol, systematic information on the bioactivity of clove polyphenols is very limited. Clove buds being one of the richest sources of dietary polyphenols with many traditional medicinal uses, the present contribution attempted to derive their standardized polyphenol-rich extracts as a water soluble free flowing powder (Clovinol) suitable for functional food applications, without the issues of its characteristic pungency and aroma. The extract was characterized by electrospray ionization-time of flight mass spectrometry (ESI-TOF-MS), and investigated for in vivo antioxidant, anti-inflammatory and anti-ulcerogenic activities. Clovinol showed significant antioxidant and anti-inflammatory effects as measured by cellular antioxidant levels, and the ability to inhibit carrageenan-induced paw swelling in mice. Further investigations revealed its significant anti-ulcerogenic activity (>97% inhibition of ethanol-induced stomach ulcers in Wistar rats when orally administered at 100 mg per kg b.w.) and up regulation of in vivo antioxidants such as superoxide dismutase (SOD), glutathione (GSH), and catalase (CAT). Clovinol also reduced the extent of lipid peroxidation among ulcer induced rats, indicating its usefulness in ameliorating oxidative stress and improving gastrointestinal health, especially upon chronic alcohol consumption. The extract was also shown to be safe and suitable for further investigations and development upon acute toxicity studies at 5 g per kg body weight and 28 days of repeated dose toxicity studies at 2.5 g per kg b.w.

Pharmacological reports about gastroprotective effects of methanolic extract from leaves of Solidago chilensis (Brazilian arnica) and its components quercitrin and afzelin in rodents

Solidago chilensis Meyenmost (Asteraceae), popularly known as "Brazilian arnica" or "arnica-do-campo," is widely used in the folk medicine to treat gastric disorders. Based on this, the gastroprotective activity of S. chilensis methanolic extract was investigated. Besides, a phytochemical study allowed isolation of two flavonoids (quercitrin and afzelin). The gastroprotective effects were investigated in acute gastric ulcer models, and the antisecretory activity was assessed in vivo and in vitro. The adhered mucus levels, reduced glutathione (GSH) content and myeloperoxidase (MPO) activity were quantified in ulcerated tissues. The contribution of isolated compounds in extract effects was evaluated, and its doses were calculated according to its yield. To evaluate the in vivo healing properties of S. chilensis methanolic extract, a chronic gastric ulcer was induced in mice by 10 % acetic acid. Evaluation of tumor necrosis factor (TNF) levels was also performed at the site of the acetic acid-induced gastric ulcer. In parallel, effects on cell viability and cell proliferation of fibroblasts (L929 cells) were determined by in vitro trials. Firstly, the S. chilensis methanolic extract (100 or 300 mg/kg) reduced the ulcer area induced by ethanol/HCl in mice when compared to the vehicle group. Moreover, the S. chilensis extract (300 mg/kg) prevented the mucus depletion, the increase in MPO activity and the decrease in the GSH levels in the ulcerated gastric tissue. The S. chilensis extract also was able to decrease the indomethacin-induced gastric ulcer in rats at a dose of 100 mg/kg. The antisecretory effect of the extract (100 mg/kg, intraduodenal (i.d.)) was confirmed by the reduction in the volume and acidity in parallel to an increase in the pH of gastric content. In addition, quercitrin (1.38 mg/kg, but not 0.46 mg/kg) and afzelin (0.026 and 0.078 mg/kg) decreased the ethanol/HCl-induced gastric ulcer. In this model, quercitrin (1.38 mg/kg) prevented the depletion of gastric GSH content and both quercitrin (1.38 mg/kg) and afzelin (0.078 mg/kg) reduced the MPO activity. These compounds also inhibited the H(+),K(+)-ATPase activity at a concentration of 1-100 μg/ml. In addition, the participation of quercitrin and afzelin in these effects also was confirmed. Furthermore, after 4 days of the treatment, an oral administration of S. chilensis methanolic extract (100 mg/kg) reduced the area of the gastric ulcer induced by acetic acid and the regeneration of the gastric mucosa was accompanied by a reduction in gastric TNF levels. The healing properties of the extract also were confirmed by enhancement of proliferation and coverage of scratched wounds in a fibroblast monolayer. Together, our results confirmed the gastroprotective effect of S. chilensis methanolic extract as well as its gastric healing potential and provided some support to the traditional use of S. chilensis for prevention and treatment of gastric lesions in complementation to its known anti-inflammatory properties.

Protective effects of trigonelline against indomethacin-induced gastric ulcer in rats and potential underlying mechanisms

The gastroprotective activity of trigonelline against indomethacin-induced ulcer and the role of anti-oxidant, anti-inflammatory and anti-apoptotic mechanisms have been explored.

NSAID-induced small intestinal damage--roles of various pathogenic factors

BACKGROUND/AIMS

NSAID-induced enteropathy has been the focus of recent basic and clinical research subsequent to the development of the capsule endoscope and double-balloon endoscope. We review the possible pathogenic mechanisms underlying NSAID-induced enteropathy and discuss the role of the inhibition of COX-1/COX-2 and the influences of food as well as various prophylactic treatments on these lesions.

METHODS

Studies were performed in experimental animals.

RESULTS

Multiple factors, such as intestinal hypermotility, decreased mucus secretion, enterobacteria, and upregulation of iNOS/NO expression, are involved in the pathogenesis of NSAID-induced enteropathy, in addition to the decreased production of PGs due to the inhibition of COX. Enterobacterial invasion is the most important pathogenic event, and intestinal hypermotility, which was associated with this event, is essential for the development of these lesions. NSAIDs also upregulate the expression of COX-2, and the inhibition of both COX-1 and COX-2 is required for the intestinal ulcerogenic properties of NSAIDs to manifest. NSAID-induced enteropathy is prevented by PGE2, atropine, ampicillin, and aminoguanidine as well as soluble dietary fiber, and exacerbated by antisecretory drugs such as proton pump inhibitors.

CONCLUSION

These findings on the pathogenesis of NSAID-induced enteropathy will be useful for the future development of intestinal-sparing alternatives to standard NSAIDs.

Protective effects of ginger and marshmallow extracts on indomethacin-induced peptic ulcer in rats

Background:

Gastric ulcer is one of the most serious diseases. Most classic treatment lines produce adverse drug reactions. Therefore, this study aimed to investigate the protective effects of two natural extracts, namely ginger and marshmallow extracts, on indomethacin-induced gastric ulcer in rats.

Materials and Methods:

Animals were divided into five groups; a normal control group, an ulcer control group, and three treatment groups receiving famotidine (20 mg/kg), ginger (100 mg/kg), and marshmallow (100 mg/kg). Treatments were given orally on a daily basis for 14 days prior to a single intra-peritoneal administration of indomethacin (20 mg/kg).

Results:

Indomethacin administration resulted in significant ulcerogenic effect evidenced by significant elevations in ulcer number, ulcer index, and blood superoxide dismutase activity accompanied by significant decreases in gastric mucosal nitric oxide and glutathione levels. In addition, elevations in gastric mucosal lipid peroxides and histamine content were observed. Alternatively, pretreatment with famotidine, ginger or marshmallow significantly corrected macroscopic and biochemical findings, supported microscopically by results of histopathological study.

Conclusion:

These results demonstrate that administration of either ginger or marshmallow extract could protect against indomethacin-induced peptic ulcer in rats presumably via their antioxidant properties and inhibition of histamine release.

Model-based prediction of the acute and long-term safety profile of naproxen in rats

BACKGROUND AND PURPOSE

Despite the increasing importance of biomarkers as predictors of drug effects, toxicology protocols continue to rely on the experimental evidence of adverse events (AEs) as a basis for establishing the link between indicators of safety and drug exposure. Furthermore, biomarkers may facilitate the translation of findings from animals to humans. Combined with a model-based approach, biomarker data have the potential to predict long-term effects arising from prolonged drug exposure. Here, we used naproxen as a paradigm to explore the feasibility of a biomarker-guided approach for the prediction of long-term AEs in humans.

EXPERIMENTAL APPROACH

An experimental toxicology protocol was set up for evaluating the effects of naproxen in rats, in which four active doses were tested (7.5, 15, 40 and 80 mg·kg(-1) ). In addition to AE monitoring and histology, a few blood samples were also collected for the assessment of drug exposure, TXB2 and PGE2 levels. Non-linear mixed effects modelling was used to analyse the data and identify covariate factors on the incidence and severity of AEs.

KEY RESULTS

Modelling results showed that besides drug exposure, maximum PGE2 inhibition and treatment duration were also predictors of gastrointestinal ulceration. Although PGE2 levels were clearly linked to the incidence rates, it appeared that ulceration severity is better predicted by measures of drug exposure.

CONCLUSIONS AND IMPLICATIONS

These results show that the use of a model-based approach provides the opportunity to integrate pharmacokinetics, pharmacodynamics and toxicity data, enabling optimization of the design, analysis and interpretation of toxicology experiments.

Herb-drug interactions between Scutellariae Radix and mefenamic acid: Simultaneous investigation of pharmacokinetics, anti-inflammatory effect and gastric damage in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Scutellariae Radix (SR), the dried root of Scutellariae baicalensis Georgi, has a lot in common with non-steroidal anti-inflammatory drugs (NSAIDs). Their similarities in therapeutic action (anti-inflammation) and metabolic pathways (phase II metabolisms) may lead to co-administration by patients with the potential of pharmacokinetic and/or pharmacodynamic interactions. The current study aims to investigate the potential interactions between SR and an NSAID, mefenamic acid (MEF), on the overall pharmacokinetic dispositions, anti-inflammatory effects and adverse effects in rats.

MATERIALS AND METHODS

The current study simultaneously monitored the pharmacokinetic and pharmacodynamic interactions in a single animal. Four groups of Sprague-Dawley rats (n=7 each) received oral doses of a standardized SR extract (300mg/kg, twice daily), MEF (40mg/kg, daily), combination of SR extract and MEF, and vehicle control, respectively, for 5 days. On Day 5, blood samples were collected after first dose over 24h for the determination of (1) plasma concentrations of SR bioactive components, MEF and its metabolites by LC-MS/MS, and (2) prostaglandin E2 (PGE2) production and cyclooxygenase-2 (COX-2) gene expression by ex vivo analyses using LPS-stimulated RAW264.7 macrophage cells, ELISA and real time-PCR. After the rats were sacrificed, stomachs were isolated to assess their gross mucosal damage. Statistical comparisons were conducted using ANOVA and t-test.

RESULTS

Minimal pharmacokinetic interaction between SR extract and MEF was observed. Co-administration of SR extract and MEF did not significantly alter the plasma concentration-time profile or the pharmacokinetic parameters such as Cmax, AUC0→24, Tmax or clearance. Pharmacodynamic interaction via the COX-2 pathway was observed. The PGE2 level in LPS-stimulated RAW264.7 cells treated with plasma collected from control group over the 24h sampling (AUC0→24[PGE2]) was 191981±8789pg/mlhr, which was significantly reduced to 174,780±6531 and 46,225±1915pg/mlhr by plasma collected from rats administered with SR extract and MEF, respectively. Co-administration of SR extract and MEF further potentiated the PGE2 inhibition, with an AUC0→24[PGE2] of 37013±2354pg/mlhr (p<0.05, compared to SR or MEF group). By analyzing the COX-2 gene expression, SR extract significantly prolonged the COX-2 inhibitory effect of MEF over the 24h (p<0.05). Furthermore, the MEF-induced stomach ulcer after the 5-day treatment, as evidenced by the increased gross ulcer index and sum of lesion length (p<0.05, compared to control), could be alleviated by co-administration with SR extract (p<0.05).

CONCLUSIONS

Co-administration of SR extract and MEF potentiated the anti-inflammatory effects, alleviated the MEF-induced stomach adverse effect while having minimal pharmacokinetic interactions. Our findings provide insight for combination therapy of SR extract and MEF against inflammatory diseases.