Beneficial Effects of Maprotiline in a Murine Model of Colitis in Normal and Reserpinised Depressed Rats

Protective Effect of Apium graveolens L. (Celery) Seeds Extracts and Luteolin on Acetic Acid-Induced Colitis in Rats

INTRODUCTION

Anti-oxidant, antispasmodic, anti-inflammatory, and analgesic effects have been reported for Apium graveolens Linn. ) Celery( seeds and its active component luteolin. So, this study was carried out to investigate the protective effects of hexane (AGHE) and methanol (AGME) extracts of A. graveolens seeds and luteolin on acetic acid-induced colitis in rats.

METHODS

Three doses of AGHE (100, 200, and 400 mg/kg), AGME (200, 400, and 800 mg/kg), and luteolin (5, 10, and 20 mg/kg) were administered orally (p.o.) to separate groups of male Wistar rats, 2 h before ulcer induction (acetic acid 4%) and continued once daily for 4 days. Prednisolone (4 mg/kg) and mesalazine (100 mg/kg) were used as reference and vehicle (2 mL/kg) as control groups. Colon biopsies were taken for weighting, macroscopic and histopathologic evaluation, and measuring myeloperoxidase (MPO) activity.

RESULTS

Our findings showed that AGHE (200 and 400 mg/kg), AGME (400 and 800 mg/kg), and luteolin (10 and 20 mg/kg) were effective to reduce colonic ulcer score, area, and index as well as total colitis index, and MPO activity significantly in comparison with controls. Since the lowest doses of extracts and luteolin were not significantly effective to diminish evaluated parameters of colitis, it is concluded that the ameliorative effect was dose related.

CONCLUSION

It is also concluded that both extracts and luteolin, as an important ingredient of celery extract, were effective in the amelioration of colitis in rats, but further clinical and detailed mechanistic experiments are required to introduce these natural agents for colitis treatment or prevention in human.

Effect of escitalopram on an acetic acid-induced ulcerative colitis model

Ulcerative colitis (UC) is a chronic and recurrent gastrointestinal (GI) disorder with an unknown aetiology and pathogenesis. Regarding the effectiveness of antidepressants on UC in animal models of depression and the known anti-inflammatory effects of escitalopram this study was conducted to evaluate the beneficial effects of escitalopram on an acetic acid-induced UC model without depression. UC model was induced by intra rectal (i.r.) administration of 4% acetic acid in rats after 24 hours of fasting. Animals were treated with three doses of escitalopram (5, 10 and 20 mg/kg). Prednisolone (4 mg/kg) was used as a reference drug in UC. Histological and oxidative stress markers were measured in all groups. Results showed significant increase in superoxide dismutase (SOD) activity and glutathione (GSH) levels, as well as significant decrease in myeloperoxidase (MPO) activity, malondialdehyde (MDA) levels, macroscopic factors (ulcer surface area, ulcer severity and weight-to-colon ratio) and microscopic and histological parameters (severity and extent of inflammation, cryptic destruction and severity of tissue involvement) in escitalopram treated rats (10, 20 mg/kg) compared to the UC group. In conclusion, the results of our study are in support of beneficial anti-inflammatory and antioxidant effects of escitalopram in UC.

Protective Effect of Two Extracts of Cydonia oblonga Miller (Quince) Fruits on Gastric Ulcer Induced by Indomethacin in Rats

BACKGROUND

In various studies, Cydonia oblonga Miller (quince) has been reported to have many properties such as antioxidant and anti-ulcerative effects. This study has aimed to investigate the protective effects of quince aqueous extract (QAE) and quince hydroalcoholic extract (QHE) on gastric ulcer caused by indomethacin and the relevant macroscopic, histopathology, and biochemical factors in rats.

METHODS

Ten groups of male Wistar rats, six in each, were used in this study. These groups included: normal (distilled water), control (distilled water + indomethacin), reference (ranitidine or sucralfate + indomethacin), and test groups (QAE or QHE + indomethacin) treated with three increasing doses (200, 500, and 800 mg/kg). Extracts and drugs were given orally to rats 1 h before injecting the indomethacin (25 mg/kg, intraperitoneally). Six hours later, the abdomen of rats was exposed, its pylorus was legated, gastric acid content was extracted, and its pH and the amount of pepsin secreted were measured by Anson method. Then, histopathology indices, ulcer area, ulcer index, and myeloperoxidase (MPO) activity were measured in gastric mucus.

RESULTS

Both extracts of quince were effective to reduce the acidity of stomach and pepsin activity. Compared to control group, the average of enzyme activity of MPO was significantly declined in all treated groups. Control group had the highest level of gastric ulcer indices including severity, area, and index while the evaluated parameters had decreased in all extract treated groups although it seems that QAE was somewhat more effective.

CONCLUSIONS

Protective effect of QAE and QHE on gastric ulcer was done by undermining offensive factors including decreasing the secretion of gastric acid and pepsin activity and by strengthening the protective factors of gastric mucus including antioxidant capacity.

Evaluation of central and peripheral effects of doxepin on acetic acid-induced colitis in rat and the involved mechanisms

Anti-colitis effect of antidepressants has been demonstrated recently. Doxepin, a tricyclic antidepressant drug (TCA), with potent H₁, H₂, alpha₁ adrenergic and muscarinic receptor blocking effects could be a good candidate for investigation for its anti-colitis activity. Moreover high prevalence of depression in patients who suffer from IBD (inflammatory bowel disease), defends this idea that adjuvant therapy with an antidepressant drug which has anti-inflammatory effect, may exert favorable effects in the control of the disease. In this study colitis was induced by acetic acid instillation into rat's colon. Doxepin was injected by intraperitoneal (10, 20, 40 mg/kg, twice daily, i.p.) or intracerebroventricular (50 and 100 microgram/rat, i.c.v.) routes to separate the mechanisms are absolutely exerted centrally or mediated both centrally and peripherally prior to induction of colitis. Dexamethasone (2 mg/kg/day, i.p.) was used as reference drug. All the treatments continued for three successive days. The effectiveness of drug was evaluated by determination of cytokines (TNFα, IL6 and IL1β) and myeloperoxidase (MPO) activity as well as macroscopic scores and histopathological parameters. Doxepin after i.p. administration was effective to reduce colitis severity through reduction in the macroscopic and microscopic colonic parameters, MPO activity and cytokines levels. Intracerebroventricular administration of the drug in contrast, did not show any significant protective effect suggesting no important central mechanisms for anti-colitis activity of doxepin. Doxepin as an ancient antidepressive drug has anti-colitis and anti-inflammatory properties which are mainly exerted peripherally so it could be introduced as a good candidate for depressed people who suffered from IBD disorders.