Ulcerative colitis is chronic and recurrent disease of the gastrointestinal tract with uncertain etiology and incomplete treatment options. N-methyl-d-aspartate (NMDA) receptor suppression has shown anti-inflammatory effects in-vitro and in-vivo. The aim of present study was to evaluate the role of dizocilpine (MK-801), a noncompetitive NMDA receptor antagonist, on TNBS (trinitrobenzene sulfonic acid)-induced murine model of colitis. Dizocilpine (0. 1, 1 and 5 mg/kg) was given to mice intraperitoneally from 24 h before induction of colitis and daily thereafter for 4 days. Dexamethasone (1 mg/kg) was used as the reference drug. Colitis was induced by intracolonic administration of TNBS/Ethanol (50/50 v/v, 40mg/kg). Animals were sacrificed 5 days after colitis induction and distal colons were examined macroscopically and microscopically. The colonic tissue level of pro-inflammatory cytokines including interleukin 1β (IL-1β ), interleukin 6 (IL-6), and tumor necrosis factor-α (TNF-α ) were assessed by ELISA. Myeloperoxidase (MPO) level was also measured in colon. Dizocilpine, particularly with intermediate dose of 1mg/kg significantly improved animal’ s weight loss as well as macroscopic and microscopic signs of colitis, reduced colonic levels of IL-1β , IL-6, TNF-α and MPO activity. Hence, dizocilpine has significant protective effects in TNBS-induced colitis and NMDA suppression may be a new and effective therapeutic strategy in ulcerative colitis via decreasing in pro-inflammatory cytokine production.

Carum carvi L. (Apiaceae family) or caraway is a common household plant grown around the world including Iran. Caraway fruits are used as flavoring agent in foods and beverages, and have various traditional uses in ethnomedicine. Anti-inflammatory, spasmolytic, antimicrobial, antioxidant, carminative and immunomodulatory properties of caraway suggest that it might exert beneficial effects on inflammatory bowel disease (IBD). Therefore, this study was carried out to investigate the effects of caraway hydroalcoholic extract (CHE) and its essential oil (CEO) in an immunological model of colitis in rats induced by trinitrobenzene sulfonic acid (TNBS). Different doses of CHE (100, 200, 400 mg/kg) and CEO (100, 200, 400 ml/kg) were administered orally (p.o.) and also doses of CHE (100, 400 mg/kg) and CEO (100, 400 ml/kg) were given intraperitoneally (i.p.) to the separate groups of male Wistar rats (n=6). Administration of the doses started 6 h after induction of colitis and continued daily for 5 consecutive days. Wet colon weight/length ratio was measured and tissue damage scores as well as indices of colitis were evaluated both macroscopically and histopathologically. CHE and CEO at all doses tested were effective in reducing colon tissue lesions and colitis indices and the efficacy was nearly the same when different doses of plant fractions were administered p.o. or i.p. Administration of prednisolone (p.o., 4 mg/kg), Asacol® (mesalazine microgranules, p.o., 100 mg/kg) and hydrocortisone acetate (i.p., 20 mg/kg) as references were effective in reducing colon tissue injures as well. These data suggest that caraway fractions are both effective and possess anti-colitic activity irrespective of the dose and route of administration.

Prunus armeniaca L. (Apricot) is a tree cultivated in different parts of the world. Apricot kernel as a good dietary supplement has shown antioxidant, anti-inflammatory and other pharmacologic properties which suggest that it may be functional as an anticolitis agent. In this study we evaluated the effects of apricot kernel extract and oil on ulcerative colitis in rats. Rats were fasted for 36 h before the experiment. Colitis was induced by intra-rectal instillation of 50 mg/kg trinitrobenzene sulfonic acid in male Wistar rats. Treatments were started 6 h after colitis induction and continued every 24 h for 5 days. Apricot kernel extract (100, 200, 400 mg/kg p.o. and 100, 400 mg/kg i.p.) and apricot kernel extract/oil (100, 200, 400 mg/kg p.o.) were used as experimental treatments and prednisolone (4 mg/kg p.o. or i.p.) was used as reference drug. On the day 6, colon tissue was removed and macroscopic and pathologic parameters were evaluated. Ulcer index and total colitis index as representative of macroscopic and histologic parameters respectively showed ameliorating effects in experimental groups especially those treated by intraperitoneal administration route. Results also demonstrated that oil fraction was not able to potentiate the effects of extract. These data suggest that apricot kernel extracts (with or without oil) can be introduced for further mechanistic and clinical studies as a complementary medicine for inflammatory bowel disorders.

Cydonia oblonga Miller (Quince) from Rosaceae family is a fruit tree cultivated in many countries mainly in Iran. This study was carried out to investigate the effect of quince juice (QJ) and quince hydroalcoholic extract (QHE) on ulcerative colitis (UC) induced by TNBS (trinitrobenzene sulfonic acid) in rats. Rats were grouped (n=6) and fasted for 36 h before colitis induction. TNBS was instilled into the colon with a hydroalcoholic carrier and then treatments were made for 5 days starting 6 h after colitis induction with different doses of QJ (200, 400, 800 mg/kg), QHE (200, 500 & 800 mg/kg) orally, QJ (400 mg/kg) and QHE (200 and 500 mg/kg) intraperitoneally. The colon tissue was removed and tissue damages were scored after macroscopic and histopathologic assessments. Albeit the examined doses of QJ and QHE were apparently effective to reduce the extent of UC lesions, only the greatest doses (500 and 800 mg/kg) resulted in significant alleviation. Weight/Length ratio as an illustrative of tissue inflammation and extravasation was also diminished with quince treatments while the results correlated with macroscopic and histopathologic evaluations. These data suggest that QJ and QHE were effective to diminish inflammation and ulcer indices in this murine model of acute colitis. Although QHE with different doses was effective in induced colitis, the dose and/or route of administration dependency was not confirmed. So quince fractions could be considered as a suitable anticolitic alternative, however further studies are needed to support this hypothesis for clinical setting.

Objective(s): In the present study, we evaluated immunological and immunomodulatory properties of royal jelly (RJ) in 2,4,6 trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats.Materials and Methods: Eighteen adult female Wistar albino rats were divided into three groups of six animals each: a control group that received only saline solution, a TNBS-induced colitis group, and a TNBS-colitis+RJ group that received 250 mg/kg/day of RJ for seven days before the induction of colitis, following by the same treatment for an additional seven days. At the end of the experiment, cardiac blood and colon samples were obtained under deep anaesthesia from the animals in all groups. Serum interleukin-1b (IL-1b), tumour necrosis factor-alpha (TNF-a) and IL-10 levels were analyzed with an enzyme-linked immunosorbent assay (ELISA). Five-micrometre-thick sections were stained with haematoxylin-eosin (H&E) for microscopic evaluations. For immunohistochemical evaluations, the paraffin sections were stained with anti-CD3 (cluster of differentiation), anti-CD5, anti-CD8 and anti-CD45.Results: The results showed that the oral RJ treatment inhibited proinflammatory cytokines, IL-1b and TNF-a secretion, while increasing anti-inflammatory cytokine IL-10 production in the TNBS-induced colitis+RJ group compared with the colitis group not treated with RJ. The colitis was not as severe in the colitis+RJ group, with ulcerative damage, weight loss and inflammatory scores suggesting that impaired CD3-, CD5-, CD8- and CD45-positive T cell immune responses likely mediated the anti-inflammatory effect.Conclusion: The antioxidant and anti-inflammatory properties of RJ protected colon mucosa against TNBS-induced colitis in rats orally treated with RJ.

Objective(s): This study was aimed at investigating immune activations of the 2, 4, 6-trinitrobenzene sulfonic acid (TNBS) -induced colitis model in colonic mucosa by immunohistochemical and Western blot methods.Materials and Methods: For this purpose, 16 female Wistar albino rats were divided into two random groups of control (n=8) and colitis (n=8). The experimental colitis model was induced by intracolonic administration of TNBS (25 mg/rat). Control animals received only rectal saline for the same time. The animals were sacrificed on the 15th day after TNBS administration, and colon tissue was removed and examined morphologically. Colon samples were stained immunohistochemically with anti-CD3, anti-CD4, anti-CD5, anti-CD8, anti-CD11b, anti-CD45, anti-TNF-a, anti-IL-17, anti-IL-22 and anti-IL-23 antibodies. Additionally, the colonic tissue IL-17 and IL-22 expressions were examined by the Western blot method.Results: In the experimental results, it was determined that there was a significant decrease in body weight and an increase in colon weight in the colitis group when comparing initial experiments. The colon tissue ulcerations, inflammation, crypt loss and Goblet cell loss were observed in the colitis group in microscopic examinations. The immunohistochemical positive cell numbers significantly increased in the colitis group. The immunoreactive lymphocytes in the propria, intracryptal and submucosal layers were found to be increased in the colitis group of rats. In addition, IL-17 and IL-23 expressions were increased in colitis colon mucosa found by Western blot analysis.Conclusion: The Th17/IL-23 pathway and IL-22 serve important roles in the pathogenesis of ulcerative colitis, and will be further examined by study.

Trinitrobenzene sulfonic acid (TNBS) -induced colitis is one of the most common methods for studying inflammatory bowel disease in animal models. Several factors may, however, affect its reproducibility, rate of animal mortality, and macroscopic and histopathological outcomes. Our aim was to validate the main contributing factors to this method and compare the effects of different reference drugs upon remission of resultant colon injuries. TNBS was dissolved in 0.25 ml of ethanol (50% v/v) and instilled (25, 50, 100 and 150 mg/kg) intracolonically to the male Wistar rats. After determination of optimum dose of TNBS in male rats and assessment of this dose in female rats, they were treated with reference drugs including dexamethasone [1 mg/kg, intraperitoneally (i.p.) and 2 mg/kg, orally (p.o.)], Asacol (mesalazine, 100 mg/kg, p.o.; 150 mg/kg, enema) and hydrocortisone acetate (20 mg/kg, i.p.; 20 mg/kg, enema) which started 2 h after colitis induction and continued daily for 6 consecutive days. Thereafter, macroscopic and microscopic parameters and clinical features were assessed and compared in different groups. We found that the optimum dose of TNBS for the reproducibility of colonic damage with the least mortality rate was 50 mg/kg. Amongst studied reference drugs, hydrocortisone acetate (i.p.), dexamethasone (i.p. and p.o.) and Asacol (p.o.) significantly diminished the severity of macroscopic and microscopic injuries and could be considered effective for experimental colitis studies in rats. Our findings suggest that optimization of TNBS dose is essential for induction of colitis under the laboratory conditions; and gender exerts no impact upon macroscopic and histological characteristics of TNBS-induced colitis in rats. Furthermore, the enema forms of hydrocortisone and Asacol are not appropriate reference drugs.