Evaluation of the anti-ulcerogenic activity of the antidepressants duloxetine, amitriptyline, fluoxetine and mirtazapine in different models of experimental gastric ulcer in rats

Investigating the synergistic effects of amitriptyline and H. pylori eradication on depressive-like behaviors and inflammatory cytokines in mice

BACKGROUND

Recent research has highlighted the potential role of Helicobacter pylori in the pathogenesis of psychiatric disorders. This study aimed to evaluate the potential synergistic effects of an antidepressant drug and H. pylori eradication therapy in a mouse model.

METHODS

Male C57BL/6 mice were divided into four groups: control, H. pylori infection, antidepressant treatment, and combined treatment. H. pylori infection was induced by oral gavage with a clinically relevant strain, and the antidepressant drug was administered via intraperitoneal injections. Behavioral tests including the forced swim test, sucrose preference test, and open field test were conducted to assess depressive-like behaviors and locomotor activity.

RESULTS

The study demonstrated that H. pylori infection induced depressive-like behaviors in mice, as evidenced by increased immobility time in the forced swim test and reduced sucrose preference. Antidepressant treatment alone partially ameliorated these behavioral changes. Strikingly, the combined treatment of the antidepressant drug and H. pylori eradication therapy led to a significantly greater reduction in depressive-like behaviors compared to either treatment alone. Furthermore, the combined treatment group exhibited increased locomotor activity in the open field test, suggesting a potential improvement in overall psychomotor functioning. ELISA assays revealed alterations in inflammatory cytokines in the H. pylori-infected mice, which were partially attenuated by the combined treatment.

CONCLUSION

The study provides novel evidence for the potential synergistic effects of an antidepressant drug and H. pylori eradication therapy in alleviating depressive-like behaviors in a mouse model.

Aibika Flower Flavonoid Extract Exhibits Antiulcer Activity in a Murine Model of Ethanol-Induced Acute Gastric Injury

Aibika (Abelmoschus manihot (L.) Medic) is a garden vegetable whose flower has been shown to have various bioactivities. This study investigated the protective effect of aibika flower flavonoid extract (AFF) on ethanol-induced gastric injury in mice. The experimental results showed that pre-feeding 125 and 250 mg AFF/kg BW for 1 week significantly reduced the gastric injury area in the negative control group from 19.2% to 6.7% and 0.6%, respectively. The results of the pathological sections staining also showed that AFF had a protective ability against alcohol-induced injury of gastric tissue and liver tissue. When the mice were exposed to high concentrations of ethanol, AFF pretreatment significantly upregulated the expression of antioxidant enzymes. The pretreatment also promoted the production of the intracellular antioxidant, reduced glutathione, in both gastric tissue and serum. On the contrary, AFF delayed the lipid peroxidation process, which, in turn, reduced the damage to the gastric mucosa. When acute inflammation was induced by ethanol stimulation, AFF significantly downregulated the proinflammatory cytokines and mediators such as TNF-α, IL-1β, IL-6, NF-κB, COX-2, and iNOS. Furthermore, AFF pretreatment greatly promoted the production of healing factors, such as matrix metalloproteinase (MMP)-2, MMP-7, and MMP-9, in the gastric tissue. In addition, AFF significantly reduced gastric cell apoptosis induced by ethanol stimulation. These results demonstrate that AFF has a good protective effect on alcohol-induced gastric ulcer and has the potential to be used in gastrointestinal health care.

Dose of selective serotonin reuptake inhibitors and risk of upper gastrointestinal bleeding in older adults

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) have been associated with an increased risk of upper gastrointestinal bleeding (UGIB) in older patients but little is known about the risk associated with individual SSRI drugs and doses.

AIMS

To quantify the risk of UGIB in relation to individual SSRI use in older adults.

METHODS

We conducted a nested case-control study within a cohort of 9565 patients aged ⩾65 years prescribed SSRIs from 2000 to 2013 using claims data of universal health insurance in Taiwan. Incident cases of UGIB during the follow-up period were identified and matched with three control subjects. Conditional logistic regression was used to estimate the odds ratio (OR) of UGIB associated with individual SSRI use and cumulative dose.

RESULTS

UGIB risk increased with the increasing cumulative doses of SSRIs (adjusted OR: 1.28, 95% confidence interval (CI): 1.02-1.62 for the highest vs. the lowest tertile). Compared with users of other SSRIs, fluoxetine users were at an increased risk of UGIB (adjusted OR: 1.25, 95% CI: 1.03-1.50) with a dose-response manner, whereas paroxetine users had 29% decreased odds (95% CI: 0.56-0.91). The increased risk was only observed among current fluoxetine users.

CONCLUSIONS

Fluoxetine therapy was associated with an increased risk of UGIB in a dose-response manner among older adults.

The role of peripheral serotonin and norepinephrine in the gastroprotective effect against stress of duloxetine

Duloxetine has been shown to produce gastroprotective effect against gastric ulcer induced by water immersion restraint stress (WIRS) via modulation of NADPH oxidases in the gastric mucosa and neurometabolites of central nucleus of amygdala. However, the underlying mechanism based on the basic pharmacological function of duloxetine-regulation on serotonin (5-HT) and norepinephrine (NE) remains unclear. Here, we found that 5-HT level in platelet-poor plasma (PPP) was decreased but NE level in plasma was increased in rats exposed to WIRS, while pretreatment with duloxetine increased 5-HT in PPP dose-dependently and decreased NE in plasma of rats after WIRS. We further showed that depletion of 5-HT by 4-chloro-DL-phenylalanine (PCPA) aggravated gastric mucosa damage and supplement of 5-HT alleviated gastric ulcers induced by WIRS. Blockade of NE receptors also mitigated the stress gastric ulcers. Using adrenalectomy and chemical blocking, we identified that it was NE from adrenal medulla rather than sympathetic nerve that was more critical in the gastroprotection of duloxetine, and intriguingly, glucocorticoid did not make a difference in WIRS-provoked gastric ulcers as a classic stress hormone. Together, our work demonstrated prophylactic protection of duloxetine from the stress gastric ulcer depended on enhancing peripheral 5-HT content and reducing NE from adrenal medulla, which provided insight into treatments of WIRS-induced gastric ulcer.

Increasing Aspartoacylase in the Central Amygdala: The Common Mechanism of Gastroprotective Effects of Monoamine-Based Antidepressants Against Stress

Monoamine-based antidepressants can prophylactically protect against stress-induced gastric ulcers. Although the central nucleus of amygdala (CeA) has been shown to modulate the severity of stress ulcers, little is known about the molecular mechanisms underlying the gastroprotective effect of this kind of drugs. Here, we first used proton magnetic resonance spectroscopy, a non-invasive tool, to explore the change of neurometabolites of the CeA of rats pretreated with the duloxetine of selective serotonin-norepinephrine reuptake inhibitors during 6 h of water-immersion restraint stress (WIRS). Duloxetine decreased N-acetyl-aspartate/creatine ratio (NAA/creatine) in CeA after WIRS, which was paralleled by the amelioration of gastric lesions. Meanwhile, the gastric ulcer index was negatively correlated with reduced NAA/creatine. Furthermore, the intra-CeA infusion of NAA aggravated WIRS-induced gastric mucosa damage, which suggested the crucial role of reduced NAA. Western blotting was performed to identify the specific enzymes responsible for the change of the contents of NAA at 0.5 h/3 h/6 h after WIRS, considering the preventative gastric protection of duloxetine. The NAA-catabolizing enzyme aspartoacylase (ASPA) was the only enzyme downregulated by 0.5 h WIRS and upregulated by duloxetine. Moreover, overexpressing ASPA in CeA alleviated stress ulcers. Additionally, all of the other three monoamine-based antidepressants, the fluoxetine of selective serotonin reuptake inhibitors, the amitriptyline of tricyclic agents, and the moclobemide of MAOs, increased ASPA expression in CeA. Together, these results indicate that increasing ASPA to hydrolyze NAA in CeA is a common mechanism of gastroprotective effects against stress exerted by monoamine-based antidepressants, and ASPA is a shared target more than monoamine regulation for this kind of drugs.

Effect of esomeprazole on lipid profile in patients with peptic ulcer

Esomeprazole; a newly introduced PPI has been widely prescribed by healthcare providers due to its improved pharmacokinetic profile. Most users could have other diseases and the PPIs are indicated as acid-suppressor to minimize gastric side effects of polypharmacy. A high percentage of users could suffer from cardiovascular diseases and lipid dysmetabolism. Hence, this study was designed to determine the impact of long-term use of esomeprazole on lipid profile in a normal subject other than having peptic ulcer for which esomeprazole has been indicated. Results confirmed that esomeprazole reduced triglyceride and HDL levels and elevated total cholesterol level and correspondingly LDL level was elevated, however, no effect was noticed with VLDL. To sum up, esomeprazole impaired lipid metabolism in apparently normal healthy individuals apart from having peptic ulcer for which the esomeprazole was indicated, this finding rise a caution during prescribing esomeprazole for the patient with multiple diseases and polypharmacy including cardiovascular ailments.

Gastroprotective effect of fluvoxamine and ondansetron on stress-induced gastric ulcers in mice

OBJECTIVES

The association between stress and gastric ulcers has been well reported. This study is divided into two parts: the first part of this study is consisted of analyzing the effect of fluvoxamine administration by intracerebroventricular (ICV) and intraperitoneal (IP) injections on stress-induced gastric ulcers. The second part investigates the effect of ondansetron in influencing the protection of the gastric mucous by giving fluvoxamine to the mice before being induced with stress.

METHODS

Water immersion restraint stress (WIRS) was used to induce stress. Fluvoxamine 50 and 100 mg/kg by IP injection, fluvoxamine 9.3 µg, and 18.6 µg by ICV injection 30 min before the induction of stress. Meanwhile, single drug and in combination administered to the mice, ondansetron 3 mg/kg was given by IP at 60 min, and fluvoxamine 50, 100 mg/kg orally at 30 min before stress induction.

RESULTS

The obtained results show fluvoxamine 50 and 100 mg/kg by IP, and fluvoxamine 18.6 µg by ICV had significantly reduced ulcer index with p<0.005, p<0.001, and p<0.005 while fluvoxamine 9.3 µg showed the insignificant result. Fluvoxamine 50 mg/kg, fluvoxamine 100 mg/kg, and ondansetron 3 mg/kg monotherapy have a significant reduction in ulcers with p<0.005, p<0.001, and p<0.05, while the combination drugs showed an insignificant reduction in ulcers.

CONCLUSIONS

Fluvoxamine with different administration routes and ondansetron monotherapy before stress reduce the occurrence of gastric ulcers, while the combination drugs did not increase the protective effect of the gastric mucosa.

The effect of adding duloxetine to lansoprazole on symptom and quality of life improvement in patients with gastroesophageal reflux diseases: A randomized double-blind clinical trial

Background:

Gastroesophageal reflux disease (GERD) is a common upper gastrointestinal disorder with a negative impact on the quality of life. This study was aimed to assess the effect of adding duloxetine to lansoprazole on the symptom and quality of life improvement in GERD patients.

Materials and Methods:

Seventy adult patients with a complaint of heartburn and regurgitation were enrolled in this randomized trial. Patients with a history of atypical symptoms, advanced systemic disease, medication-induced symptom, structural lesion in endoscopy, allergy to the medication, and unco-operative were excluded. The patients randomly (computer generated table) assigned in Groups A who received lansoprazole 30 mg plus placebo daily and Group B, in which duloxetine 30 mg daily replaced by placebo during 4 weeks. All of participants, care-givers, and outcomes assessors were blinded. Basic demographic data, symptom severity score, depression and anxiety Beck score, and quality of life questionnaire were recorded at the starting and ending of treatment.

Results:

Fifty-four patients have completed the study. The mean difference of Anxiety Beck score (13, 95% confidence interval [CI] [10–16], P = 0.001) and total raw score of quality of life (7, 95% CI [3.89–10.11], P = 0.043) were significantly improved in Group B. Complete and overall heartburn improvement rates were significantly better in Group B (odds ratio [OR] Adj: 2.01, 95% CI [1.06–2.97] and OR Adj: 1.31, 95% CI [1.05–1.57], respectively).

Conclusion:

We found that the combination of duloxetine and lansoprazole is a safe and tolerable regimen, and it can significantly improve anxiety, heartburn, coffee consumption, the quality of sleep, and life in patients who suffer from the symptoms of GERD.

DUOX2, a common modulator in preventive effects of monoamine-based antidepressants on water immersion restraint stress- and indomethacin- induced gastric mucosal damage

Multiple kinds of monoamine-based antidepressants have been shown prophylactic effects in experimentally induced gastric ulcer. The loss of redox homeostasis plays a principle role in the development of peptic mucosal damage. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases are one of the most important sources of reactive oxygen species within the gastrointestinal tract. It is unclear whether there are some common NADPH oxidases modulated by monoamine-based antidepressants in different gastric mucosal damage models. We explored the effects of selective serotonin-norepinephrine reuptake inhibitor (SNRI) duloxetine on the reactive oxygen species production and antioxidant capacity in the gastric mucosa of water immersion restraint (WIRS) or indomethacin treated rats, and examined the role of NADPH oxidases in the protective effects. Pretreated duloxetine prevented the increase of gastric mucosal NADPH oxidase activity and NADPH oxidase inhibitor apocynin dose-dependently protected gastric mucosa from damage by the two factors. Furthermore, dual oxidase 2 (DUOX2) and NADPH oxidase4 (NOX4) are involved in the protective effects of duloxetine in both models. We then examined NADPH oxidases expression modulated by the other monoamine-based antidepressants including selective serotonin reuptake inhibitor (SSRIs) fluoxetine, tricyclic agent (TCAs) amitriptyline and monoamine oxidase inhibitor (MAOs) moclobemide in the two models, and all the three antidepressants reduced the DUOX2 expression in the gastric mucosa. So DUOX2 was a common modulator in the preventive effects of all the monoamine-based antidepressants on WIRS- and indomethacin-induced gastric lesion. Our work provided a peripheral joint molecular target for monoamine modulatory antidepressants, which may be helpful to reveal the mechanisms of this kind of drugs more than monoamine regulation.

Flavonoid-Rich Extract of Dissotis rotundifolia Whole Plant Protects against Ethanol-Induced Gastric Mucosal Damage

Dissotis rotundifolia is a plant in the family Melastomataceae. The methanolic extract of the whole plant is reported to be rich in C-glycosylflavones such as vitexin and orientin. Though there are several reports on the ethnomedicinal use of this plant extract in stomach ulcers, experimental-based data is unavailable. The drive for carrying out this research was to obtain data on the possible ameliorative effect of the whole plant extract of Dissotis rotundifolia (DRE) in gastric ulcerations induced by ethanol in Sprague Dawley (SD) rats. SD rats were pretreated with 100, 300, and 500 mg/kg of DRE for 14 days after which an ulcerogen-ethanol was administered. Gross examinations of the stomach lining and histological analysis of gastric lesions were carried out coupled with an assessment of the antioxidant activity of gastric mucosa using MDA, GSH, CAT, and SOD as indicators. The data suggested a significant attenuation in gastric mucosal damage in DRE-pretreated ethanol-induced gastric ulcer reflected in the antioxidant status. There was also a reduction or absence of hemorrhage, edema, and leucocytes infiltration in DRE-treated groups compared to the negative control group. DRE conserved glutathione (GSH) levels, reduced malondialdehyde (MDA) levels, and enhanced catalase (CAT) and superoxide dismutase (SOD) enzyme levels. The present study shows that DRE possess protective effects against ethanol-induced ulcer damage in the stomach of rats, which could be attributed to its antioxidant activity.

Effects of Low-Frequency Pulsed Electromagnetic Fields on High-Altitude Stress Ulcer Healing in Rats

High-altitude stress ulcer (HSU) has constantly been a formidable clinical challenge for high-altitude and severe hypoxia. Pulsed electromagnetic fields (PEMFs) have been verified to have the ability to penetrate tissues, and the biological effects have been confirmed effective on various tissue restorations. However, the therapeutic effect of PEMFs on HSU has been rarely reported. This study aimed to evaluate the effects of PEMFs on HSU healing systematically. Sprague–Dawley rats were assigned to control, HSU, and HSU+PEMF groups. The HSU models were induced by restraint stress under low-pressure hypoxia. The HSU+PEMF group was subjected to PEMF exposure. During the HSU healing, gastric juice pH values, ulcer index (UI), and histopathologic changes were investigated. Furthermore, tumor necrosis factor-α (TNF-α) was determined to analyze the severity of gastric membrane inflammations. Norepinephrine (NE), which influences gastric acid secretion, was measured. Results indicated the UI of the HSU+PEMF decreased faster than that of the HSU group. Histopathologic observation suggested that the ulcer tissue healing is faster in the HSU+PEMF group than in the HSU group. The TNF-α/total protein results revealed that the inflammation of the HSU+PEMF group is suppressed effectively. The pH values are higher in the HSU+PEMF group than in the HSU, as confirmed by NE examination. The results indicated that low-frequency PEMFs can penetrate stomach tissues to relieve the symptoms of HSU and promote the regeneration of disturbed tissues, thus implying the clinical potential of PEMF therapy for HSU treatment.

In Vivo Gastroprotective and Antidepressant Effects of Iridoids, Verbascoside and Tenuifloroside from Castilleja tenuiflora Benth

Stress is an important factor in the etiology of some illnesses such as gastric ulcers and depression. Castilleja tenuiflora Benth. (Orobanchaceae) is used in Mexican traditional medicine for the treatment of gastrointestinal diseases and nervous disorders. Previous studies indicated that organic extracts from C. tenuiflora had gastroprotective effects and antidepressant activity. In this study, we aimed to evaluate the gastroprotective and antidepressant activity of fractions and isolated compounds from the methanolic extract (MECt) of C. tenuiflora in stressed mice. Chromatographic fractionation of MECt produced four fractions (FCt-1, FCt-2, CFt-3, and FCt-4) as well as four bioactive compounds which were identified using TLC, HPLC and NMR analyses. The cold restraint stress (CRS)-induced gastric ulcer model followed by the tail suspension test and the forced swim test were used to evaluate the gastroprotective effect and antidepressant activity of the extract fractions. FCt-2 and FCt-3 at 100 mg/kg had significant gastroprotective and antidepressant effects. All isolated compounds (verbascoside, teniufloroside and mixture geniposide/ musseanoside) displayed gastroprotective effects and antidepressant activity at 1 or 2 mg/kg. The above results allow us to conclude that these polyphenols and iridoids from C. tenuiflora are responsible for the gastroprotective and antidepressant effects.

Expression of tryptophan hydroxylase in gastric mucosa in symptomatic and asymptomatic Helicobacter pylori infection

INTRODUCTION

Helicobacter pylori infection induces clinical symptoms in 15-20% of subjects, and the reason for this variation is still not clear. The aim of the present study is to evaluate the expression of tryptophan hydroxylase (TpH-1) in gastric mucosa of patients with symptomatic and asymptomatic H. pylori infection in relation to the intensity of bacterial colonization and severity of dyspeptic symptoms.

MATERIAL AND METHODS

Ninety subjects (aged 35-49 years) were enrolled in the study and separated into 3 groups of 30 subjects each. Group I - healthy volunteers without H. pylori infection, group II - subjects with asymptomatic H. pylori infection, group III - H. pylori-infected patients with dyspeptic symptoms, mainly fasting and nocturnal epigastric pain. To diagnose H. pylori infection the urea breath test (UBT-13C) and histological analysis were performed. The level of mRNA expression of tryptophan hydroxylase (TpH-1) was estimated in gastric mucosa with RT-PCR.

RESULTS

The expression of this enzyme in antral mucosa was 2.69 ±0.97 in group I, 2.28 ±0.69 in group II (p > 0.05) and 4.40 ±1.64 in group III (p < 0.001). The levels of expression of TpH-1 in gastric body mucosa were 2.16 ±0.70, 1.57 ±0.52 (p > 0.05) and 3.40 ±1.51 (p < 0.001), respectively. In group III a positive correlation was found between intensity of H. pylori colonization and TpH-1 expression as well as between TpH-1 expression and severity of dyspeptic symptoms.

CONCLUSIONS

Increased expression of TpH-1 in gastric mucosa plays a role in pathogenesis of chronic dyspepsia.

Selective serotonin reuptake inhibitor fluvoxamine ameliorates stress- and NSAID-induced peptic ulcer possibly by involving Hsp70

Background Selective serotonin reuptake inhibitors (SSRIs) have recently become potential candidates for a new therapeutic approach to ulcer and gastric bleeding. Heat shock protein 70 (Hsp70) plays an important role in cellular resistance to nonsteroidal anti-inflammatory drugs (NSAIDs). However, there is lack of evidence that fluvoxamine recruits Hsp70 to affect stress-induced gastric ulcer. Therefore, we investigated the effect of fluvoxamine on NSAID- and stress-induced gastric ulcer and the possible involvement of Hsp70. Methods ICR mice were used in the study. Stress induction was made by the water-immersion-plus-restraint method. NSAID-induced gastric ulcer was produced by oral administration of indomethacin. Fluvoxamine was given orally 30 min before stress induction and indomethacin treatment. Results Stress and indomethacin treatment significantly increased the ulcer index and intraluminal bleeding score. Stress and indomethacin treatment also significantly increased the expression of Hsp70. Fluvoxamine significantly decreased the ulcer index and intraluminal bleeding in both ulcer models. Moreover, fluvoxamine further increased the expression of Hsp70 in the gastric tissue of stress- and indomethacin-treated mice. Conclusions Our results indicate that fluvoxamine may have a protective effect against stress- as well as NSAID-induced gastric ulcer. In addition, the present study suggests the possible involvement of Hsp70 in the amelioration of gastric ulcer by fluvoxamine.

Isolation, characterization, and in silico, in vitro and in vivo antiulcer studies of isoimperatorin crystallized from Ostericum koreanum

CONTEXT

Ostericum koreanum (Maxim.) Kitagawa (Apiaceae) roots are traditionally used as an analgesic and antiulcer agent. However, the antiulcer potential of isoimperatorin isolated from O. koreanum has not yet been explored.

AIM

To evaluate the antiulcer activity of isoimperatorin isolated from the roots of O. koreanum.

MATERIALS AND METHODS

Isoimperatorin was isolated as cubic crystals by repeated column chromatography of the ethyl acetate fraction and structure was verified with ¹H NMR, ¹³C NMR and high-resolution mass spectrometry (HRMS-FAB). The crystals obtained were analyzed with the single crystal X-ray method. The MTT assay was used to determine its cytotoxicity against chondrocytes at different concentrations (0.0-737.74 μM, 24 h). The in vivo antiulcer activity of isoimperatorin (40 mg/kg) was determined against ethanol-, indomethacin- and pyloric ligation-induced ulcers in Sprague-Dawley rats. Furthermore, the effect of isoimperatorin (0.0-737.74 μM, 24 h) on the expression of type II collagen in chondrocytes was determined using western blot method. The in vitro urease inhibitory activity of isoimperatorin (0-80 μM) and molecular docking was also performed against urease.

RESULTS AND DISCUSSION

Isoimperatorin demonstrated significant inhibitory activity (IC₅₀ 36.43 μM) against urease as compared to the standard drug thiourea (IC₅₀ 33.57 μM) without cytotoxic effects. It provided 70.9%, 67.65% and 54.25% protection in ulcer models induced by ethanol, indomethacin and pyloric ligation, respectively. Isoimperatorin showed the highest expression level of type II collagen at 368.87 μM. The docking results confirmed strong binding affinity with the target protein.

CONCLUSION

Isoimperatorin may be used to develop antiulcer drugs with decreased side effects.

Dhiyaaldeen S, Abdulaziz Bardi D, M. Salama S, Rouhollahi E, Karimian H, Abdolmalaki R, Azizan AHS, Mohd Ali H, Mohd Noor S, Abdulla MA. The Gastroprotective Effect of Vitex pubescens Leaf Extract against Ethanol-Provoked Gastric Mucosal Damage in Sprague-Dawley Rats

Vitex pubescens is a Malaysian therapeutic plant employed in traditional drug to remedy a variety of disorders. The purpose of this research is to assess the gastroprotective efficiency of V. pubescens leaves against ethanol-induced gastric hemorrhagic laceration in rats. Animals were randomly allocated into seven groups and pre-treated, separately, with 10% Tween 20 (normal and ulcer control groups), 20 mg/kg omeprazole (reference group), and 62.5, 125, 250, and 500 mg/kg of V. pubescens extract (experimental groups). All animals were sacrificed after another hour. Histological evaluation of the ulcer control group revealed significant injury to the gastric mucosa with edema and leucocyte infiltration of the submucosal layer. PAS staining, showed remarkably intense magenta color, remarkable increase of HSP70 and decrease of Bax proteins in rats pre-treated with plant extracts compared to the ulcer control group. Gastric homogenates revealed a remarkable increase in endogenous antioxidant enzyme activities (CAT, SOD, GSH) and a decrease in the lipid peroxidation level (MDA) in animals pre-treated with V. pubescens extract compared with the ulcer control group. The gastroprotective activity of this plant might be related to increased antioxidant enzymes and decrease lipid peroxidation upsurge of HSP70 and reduced expression of Bax proteins.

Simultaneous determination of cucurbitacin IIa and cucurbitacin IIb of Hemsleya amabilis by HPLC-MS/MS and their pharmacokinetic study in normal and indomethacin-induced rats

A selective and sensitive HPLC-MS/MS method was developed for the simultaneous determination of cucurbitacin IIa (cuIIa) and cucurbitacin IIb (cuIIb), the major bioactive cucurbitacins of Hemsleya amabilis, in rat plasma using euphadienol as internal standard (IS). After liquid-liquid extraction with dichloromethane, separation was achieved on a Syncronis HPLC C18 column (150 mm × 4.6 mm, 5 μm) using an isocratic mobile phase system consisting of acetonitrile-water (85:15, v/v) at a flow rate of 0.6 mL/min with a split ratio of 1:2. Detection was performed on a TSQ Quantum Ultra mass spectrometer equipped with an positive-ion electrospray ionization source. The lower limits of quantification (LLOQs) were 0.25 and 0.15 ng/mL for cuIIa and cuIIb, respectively. The intra- and inter-day precision was <11.5% for the LLOQs and each quality control level of the analytes, and accuracy was between -9.1 and 7.6%. The extraction recoveries of the analytes and IS from rat plasma were all >87.1%. The method was fully validated and applied to compare the pharmacokinetic profiles of the two cucurbitacins in rat plasma after oral administration of H. amabilis extract between normal and indomethacin-induced rats. Copyright © 2016 John Wiley & Sons, Ltd.

Serotonin and histamine mediate gastroprotective effect of fluoxetine against experimentally-induced ulcers in rats

Research in the treatment of gastric ulcer has involved the investigation of new alternatives, such as anti-depressant drugs. The present study was designed to investigate the gastroprotective effects of fluoxetine against indomethacin and alcohol induced gastric ulcers in rats and the potential mechanisms of that effect. Fluoxetine (20 mg/kg) was administered IP for 14 days. For comparative purposes, other rats were treated with ranitidine (30 mg/kg). Thereafter, after 24 h of fasting, INDO (100 mg/kg) or absolute alcohol (5 ml/kg) was administered to all rats (saline was administered to naïve controls) and rats in each group were sacrificed 5 h (for INDO rats) or 1 h (for alcohol rats) later. Macroscopic examination revealed that both fluoxetine and ranitidine decreased ulcer scores in variable ratios, which was supported by microscopic histopathological examination. Biochemical analysis of fluoxetine- or ranitidine-pre-treated host tissues demonstrated reductions in tumor necrosis factor (TNF)-α and myeloperoxidase (MPO) levels and concomitant increases in gastric pH, nitric oxide (NO) and reduced glutathione (GSH) contents. Fluoxetine, more than ranitidine, also resulted in serotonin and histamine levels nearest to control values. Moreover, immuno-histochemical analysis showed that fluoxetine markedly enhanced expression of cyclo-oxygenases COX-1 and COX-2 in both models; in comparison, ranitidine did not affect COX-1 expression in either ulcer model but caused moderate increases in COX-2 expression in INDO-induced hosts and high expression in alcohol-induced hosts. The results here indicated fluoxetine exhibited better gastroprotective effects than ranitidine and this could be due to anti-secretory, anti-oxidant, anti-inflammatory and anti-histaminic effects of the drug, as well as a stabilization of gastric serotonin levels.

Antidepressants and Gastric Cancer: A Nationwide Population-Based Nested Case-Control Study

BACKGROUND

To our knowledge, no epidemiological study has reported on whether an association between antidepressant exposure and gastric cancer exists. Herein, we aim to investigate the possible association between antidepressant exposure and gastric cancer incidence.

METHODS

Using a nested case-control design, we identified 26289 cases with gastric cancer and 127984 controls from Taiwan's National Health Insurance Research Database (NHIRD). The data were analyzed using a conditional logistic regression model adjusting for possible confounding variables.

RESULTS

We found antidepressant use did not increase the risk of gastric cancer. The lack of an association between antidepressant prescription and elevated gastric cancer incidence was apparent for across selective serotonin-reuptake inhibitors (SSRIs), tricyclic agents (TCAs), serotonin-norepinephrine reuptake inhibitors (SNRIs), reversible inhibitors of monoamine oxidase A (RIMA), trazodone, mirtazapine and bupropion. There were slightly decreased gastric cancer risks of SSRIs use (≧28 DDD group, adjusted OR = 0.87; 95% CI = 0.78-0.96). Sensitive analysis showed SSRIs, TCAs, and SNRIs did not increase gastric cancer risks significantly even in the group with peptic ulcer history.

CONCLUSIONS

An association between antidepressant exposure and gastric cancer was not apparent in this analysis.

Alkaloids from Mahonia bealei posses anti-H⁺/K⁺-ATPase and anti-gastrin effects on pyloric ligation-induced gastric ulcer in rats

The purpose of this study was to investigate the underlying mechanism(s) of the total alkaloids (TA) from Mahonia bealei in treating pyloric ligation-induced gastric ulcers in rats. Animals were sacrificed after 19 h of the ligation. Gastric acid, peptic activities, mucin levels, H(+)/K(+)-ATPase activities and the gastrin level were analyzed. To improve the accuracy of the observations, IPP 6.0 software was introduced to measure the area of ulcer. TA (18.56 mg/kg/day, i.g.) showed an antiulcer effect by significantly decreasing the gastric ulcer areas (11.28 mm(2)) compared with model group (26.36 mm(2)). The TA ulcer inhibition ratio was 57.2%, compared with the effect of the positive control, omeprazole (62.96%). The results also showed that TA had a significant effect in inhibiting the release of H(+)/K(+)-ATPase, reducing the content of gastrin and decreasing gastric acidity on experimental animals. However, the TA had no significant effects on gastric mucus secretion and pepsin activity. Data indicated that TA had gastric ulcer protective effects by modulating the H(+)/K(+)-ATPase activity and gastrin level. TA has a potential to be developed as a pharmacological agent for the treatment of gastric ulcers.

Gastric barrier function and toxic damage

Gastric epithelium is the first significant barrier between the inner body and the potentially toxic material in the lumen. Nutrients affect gastric barrier continuously--alcohol, coffee, spices, salted food, etc. Also, very potent noxious agents are widely prescribed drugs--nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin and selective serotonin reuptake inhibitors. Helicobacter pylori is a well-known and well-investigated pathogen associated with serious gastric damage and gastric carcinoma. For its defense and maintenance of homeostasis and integrity, except acid secretion and maintenance of low luminal pH, gastric mucosa also has a specific structure, and its function is influenced by different control mechanisms. These include control of mucosal blood flow, control of mucus and bicarbonate secretion, constant cell renewal, and neuronal and hormonal control of defense mechanisms. These mechanisms are mediated by prostaglandins, nitric oxide, growth factors, heat-shock proteins and a neuropeptide called calcitonin gene-related protein. Adrenal glucocorticoids and the central nervous system also play an important role in regulating gastro-protection, especially hypothalamus and the dorsal vagal complex. Gastric mucosa is also an important component of the body's immune system and gut-associated lymphoid tissue which serves as the initiation site for antigen-specific humoral and cell-mediated immune response. Treatment options for gastric barrier dysfunction and damage due to aforementioned noxious agents are guided by the nature of damage and our understanding of the pathophysiological mechanisms involved. Currently, management is guideline driven and depends upon eradication treatment in patients infected with H. pylori and treatment or prevention of aspirin or NSAID ulceration.

The effect of a minor constituent of essential oil from Citrus aurantium: the role of β-myrcene in preventing peptic ulcer disease

The monoterpene β-myrcene has been widely used in cosmetics, food and beverages, and it is normally found in essential oil from citrus fruit. The aim of this study was to investigate the anti-ulcer effects of β-myrcene on experimental models of ulcers that are induced by ethanol, NSAIDs (non-steroidal anti-inflammatory drugs), stress, Helicobacter pylori, ischaemia-reperfusion injury (I/R) and cysteamine in order to compare with the essential oil of Citrus aurantium and its major compound limonene. The results indicate that the oral administration of β-myrcene at a dose of 7.50mg/kg has important anti-ulcer activity with significantly decreased gastric and duodenal lesions as well as increased gastric mucus production. The results showed treatment with β-myrcene caused a significant increase in mucosal malondialdehyde level (MDA), an important index of oxidative tissue damage. The β-myrcene was also endowed with marked enhancement of antioxidant enzyme activity from GR system as evidenced by the decreased activity of superoxide dismutase (SOD) and increased levels of glutathione peroxidase (GPx), glutathione reductase (GR), and total glutathione in gastric tissue. Our results also shown that treatment with β-myrcene is not involved with thioredoxin reductase (TrxR) activity. Our results reveal, for the first time, the importance of β-myrcene as an inhibitor of gastric and duodenal ulcers and demonstrate that an increase in the levels of gastric mucosa defence factors is involved in the anti-ulcer activity of β-myrcene.

Metabolomics coupled with multivariate data and pathway analysis on potential biomarkers in gastric ulcer and intervention effects of Corydalis yanhusuo alkaloid

Metabolomics, the systematic analysis of potential metabolites in a biological specimen, has been increasingly applied to discovering biomarkers, identifying perturbed pathways, measuring therapeutic targets, and discovering new drugs. By analyzing and verifying the significant difference in metabolic profiles and changes of metabolite biomarkers, metabolomics enables us to better understand substance metabolic pathways which can clarify the mechanism of Traditional Chinese Medicines (TCM). Corydalis yanhusuo alkaloid (CA) is a major component of Qizhiweitong (QZWT) prescription which has been used for treating gastric ulcer for centuries and its mechanism remains unclear completely. Metabolite profiling was performed by high-performance liquid chromatography combined with time-of-flight mass spectrometry (HPLC/ESI-TOF-MS) and in conjunction with multivariate data analysis and pathway analysis. The statistic software Mass Profiller Prossional (MPP) and statistic method including ANOVA and principal component analysis (PCA) were used for discovering novel potential biomarkers to clarify mechanism of CA in treating acid injected rats with gastric ulcer. The changes in metabolic profiling were restored to their base-line values after CA treatment according to the PCA score plots. Ten different potential biomarkers and seven key metabolic pathways contributing to the treatment of gastric ulcer were discovered and identified. Among the pathways, sphingophospholipid metabolism and fatty acid metabolism related network were acutely perturbed. Quantitative real time polymerase chain reaction (RT-PCR) analysis were performed to evaluate the expression of genes related to the two pathways for verifying the above results. The results show that changed biomarkers and pathways may provide evidence to insight into drug action mechanisms and enable us to increase research productivity toward metabolomics drug discovery.

Gastroprotective effect of desmosdumotin C isolated from Mitrella kentii against ethanol-induced gastric mucosal hemorrhage in rats: possible involvement of glutathione, heat-shock protein-70, sulfhydryl compounds, nitric oxide, and anti-Helicobacter pylori activity

BACKGROUND

Mitrella kentii (M. kentii) (Bl.) Miq, is a tree-climbing liana that belongs to the family Annonaceae. The plant is rich with isoquinoline alkaloids, terpenylated dihydrochalcones and benzoic acids and has been reported to possess anti-inflammatory activity. The purpose of this study is to assess the gastroprotective effects of desmosdumotin C (DES), a new isolated bioactive compound from M. kentii, on gastric ulcer models in rats.

METHODS

DES was isolated from the bark of M. kentii. Experimental rats were orally pretreated with 5, 10 and 20 mg/kg of the isolated compound and were subsequently subjected to absolute ethanol-induced acute gastric ulcer. Gross evaluation, mucus content, gastric acidity and histological gastric lesions were assessed in vivo. The effects of DES on the anti-oxidant system, non-protein sulfhydryl (NP-SH) content, nitric oxide (NO)level, cyclooxygenase-2 (COX-2) enzyme activity, bcl-2-associated X (Bax) protein expression and Helicabacter pylori (H pylori) were also investigated.

RESULTS

DES pre-treatment at the administered doses significantly attenuated ethanol-induced gastric ulcer; this was observed by decreased gastric ulcer area, reduced or absence of edema and leucocytes infiltration compared to the ulcer control group. It was found that DES maintained glutathione (GSH) level, decreased malondialdehyde (MDA) level, increased NP-SH content and NO level and inhibited COX-2 activity. The compound up regulated heat shock protein-70 (HSP-70) and down regulated Bax protein expression in the ulcerated tissue. DES showed interesting anti-H pylori effects. The efficacy of DES was accomplished safely without any signs of toxicity.

CONCLUSIONS

The current study reveals that DES demonstrated gastroprotective effects which could be attributed to its antioxidant effect, activation of HSP-70 protein, intervention with COX-2 inflammatory pathway and potent anti H pylori effect.

Antidepressant-like effect of ethanol extract from Zuojin Pill, containing two herbal drugs of Rhizoma Coptidis and Fructus Evodiae, is explained by modulating the monoaminergic neurotransmitter system in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Zuojin Pill (ZJP), a traditional Chinese medicinal decoction, contains two herbal drugs: Coptis chinensis Franch. and Evodia rutaecarpa (Juss.) Benth. in the ratio of 6:1 (w/w). Previous pharmacological studies have shown that two herbs in ZJP have the antagonistic effects on catecholamine secretion in bovine adrenal medullary cells. Furthermore, the alkaloids from the two herbs in ZJP may provide a protective effect for depression in individuals with a low expressing 5-HTT allele by increasing receptor concentration in serotonergic neurons. However, antidepressant effect has not been reported before and has not been fully clarified.

AIM OF THE STUDY

The present study aimed to investigate the antidepressant potential of ethanol extract from ZJP and its monoaminergic mechanism in mice.

MATERIALS AND METHODS

Seven alkaloids were determined from the ethanol extract of ZJP using High Performance Liquid Chromatography (HPLC) with the gradient mobile phase. The ethanol extract from ZJP was used to evaluate the antidepressant potential in mice. Mouse models of depression including the tail suspension test (TST) and the forced swim test (FST) were used to evaluate the effects of the ethanol extract from ZJP. A possible mechanism was explored in the tests of antagonism of reserpine-induced ptosis and hypothermia, and 5-HTP induced head twitch response in mice. The contents of monoamine neurotransmitters including norepinephrine (NE), serotonin (5-hydroxytryptamine or 5-HT) in hippocampus of mice and NE, 5-HT, dopamine (DA) in striatum of mice were determined by HPLC system with Electrochemical Detector (ECD).

RESULTS

The results showed that intragastric administration of the ethanol extract from ZJP (5, 10, 20mg/kg) or fluoxetine (7.5mg/kg) significantly reduced the duration of immobility in TST and FST. However, the effect was not dose-dependent. Ethanol extract from ZJP (5, 10, 20mg/kg) also increased the accumulative number of the 5-HTP-induced head twitch response in mice. The mice were treated with the ethanol extract from ZJP (5, 10, 20mg/kg) or fluoxetine (7.5mg/kg), which could antagonize reserpine-induced ptosis and hypothermia, moreover, both of them could elevate the contents of NE, 5-HT in hippocampus as well as NE, 5-HT, DA in striatum significantly.

CONCLUSION

These results indicate that the ethanol extract from ZJP produced antidepressant-like effect and the possible mechanism, at least in part, is via the central monoaminergic neurotransmitter system and 5-HT plays a major role.