A new chronic ulcerative colitis model produced by combined methods in rats

Cinnamyl Sulfonamide Hydroxamate Derivatives Inhibited LPS-Stimulated NF-kB Expression in RAW 264.7 Cells In Vitro and Mitigated Experimental Colitis in Wistar Rats In Vivo

BACKGROUND

Histone deacetylase (HDAC) inhibition has been found to be effective in the treatment of inflammatory bowel disease. Previous studies have reported that Cinnamyl sulfonamide hydroxamate derivatives possess non-selective HDAC inhibition.

OBJECTIVE

The present study was designed to screen three selected Cinnamyl sulfonamide hydroxamate derivatives, NMJ-1, NMJ-2, and NMJ3, for in vitro anti-inflammatory response by assessing the expression of pNF-κB in lipopolysaccharide (LPS)-induced inflammatory changes on RAW 264.7 cells, and in vivo anti-inflammatory response in acetic acid (AA) and 2.4-dinitrochlorobenzene (DNCB)-induced colitis models in Wistar rats.

METHOD

AA-induced colitis was produced in Wistar rats by intra-colonic administration of 1 ml AA. DNCBinduced colitis was produced by spraying 250 μL DNCB in acetone (20g/L) on the nape of the rats for 14 days, followed by the intracolonic administration on day 15. Drugs were administered for three days after the induction of colitis.

RESULTS

In vitro anti-inflammatory effect was observed by NMJ1 and NMJ2 through a significant decrease in pNF-κB overexpression-induced by LPS. Similar effect was observed in anti-colitis response by NMJ2 in both models by reversing the colitis-induced changes in length, weight, anti-oxidant profile and histopathology of the colon.

CONCLUSION

NMJ2 was found to be most effective among the tested compounds as an anti-inflammatory agent in both in vitro and in vivo inflammatory studies.

LL202 protects against dextran sulfate sodium-induced experimental colitis in mice by inhibiting MAPK/AP-1 signaling

LL202, a newly-synthesized flavonoid derivative, has been reported to inhibit inflammatory-induced angiogenesis. However, the exact role of LL202 in inflammation along with its mechanism has not been explored. In this study, we investigated the anti-inflammatory effect of LL202 on intestinal inflammation by establishing dextran sulfate sodium (DSS)-induced experimental colitis. LL202 attenuated DSS-induced body weight loss, colon length shortening and colonic pathological damage. The inflammatory cells infiltration, myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) activities were decreased by LL202 in a dose-dependent manner. LL202 reduced the production of pro-inflammatory cytokines in serum and colon of DSS-induced mice as well. Mechanically, LL202 could decrease the expression and nuclear translation of AP-1 to protect against DSS-induced colitis. In lipopolysaccharide (LPS)-induced THP-1 cells, LL202 markedly decreased the secretion, mRNA level and protein expression of IL-1β, IL-6 and TNF-α via inhibiting ERK/JNK/p38 MAPK pathways and the nuclear translocation of AP-1. Furthermore, these findings were confirmed in LPS-induced bone marrow derived macrophages (BMDM). In conclusion, our study demonstrated that LL202 could exert its anti-inflammatory effect via inhibiting MAPK/AP-1 signaling, which suggested that LL202 might be a potential effective drug for the treatment of inflammatory bowel diseases.

Thyroid Dysfunction, Neurological Disorder and Immunosuppression as the Consequences of Long-term Combined Stress

Stress is a powerful modulator of neuroendocrine, behavioral, and immunological functions. So far, the molecular mechanisms of response to stressors still remain elusive. In the current study, after 10 days of repeated chronic stress (hot-dry environment and electric foot-shock), a murine model of combined-stress (CS) was created in the SPF Wistar rats. Meanwhile, we established an ulcerative-colitis (UC) rat model induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS)/ethanol enema according to previous studies. The blood, hypothalamus, and colon tissues of these rats from CS, normal control (NC), UC and sham (SH) groups, were collected for further investigations. Comparing to the NC group, the serum levels of T3, T4, fT3 and fT4 were obviously decreased in the CS group after chronic stress, indicating that thyroid dysfunction was induced by long-term combined stress. Moreover, the application of RNA-seq and subsequent analyses revealed that neurological disorder and immunosuppression were also caused in the hypothalamus and colon tissues, respectively. Comparing with SH group, besides the induced colon inflammation, thyroid dysfuntion and neurological disorder were also produced in the UC group, suggesting that hypothalamic-pituitary-thyroid (HPT) axis and gastrointestinal system might not function in isolation, but rather, have intricate crosstalks.

Protective effect of Periplaneta americana extract in ulcerative colitis rats induced by dinitrochlorobenzene and acetic acid

CONTEXT

Periplaneta americana L. (Dictyoptera; Blattaria) has been traditional used to treat ulcers, burns and heart disease in southwestern China. Recent reports indicate that P. americana can be used as an alternative medicine in therapy of ulcerative colitis, but the mechanism involved remains obscure.

OBJECTIVE

This study investigated the therapeutic effect of P. americana extract (PAE) in rat colitis and elucidated its potential mechanism.

MATERIALS AND METHODS

Dinitrochlorobenzene and acetic acid-induced colitis rat model was applied. Colitis rats were treated with PAE for 10 d and estimated disease activity index daily. Rectal inflammation was assessed by myeloperoxidase activity and histological changes. Another colitis rats were treated with PAE for 4 d, meanwhile gavage with Escherichia coli labelled with green fluorescent protein. Mesenteric lymph nodes, colon, liver, spleen and kidney were harvested for bacteria culture. PAE was suspended in distilled water then partitioned with ethyl acetate and n-butanol to obtain ethyl acetate fraction, n-butanol fraction and water fraction, respectively. Fibroblasts proliferation and collagen accumulation of each fraction was determined.

RESULTS

PAE treatment reduced the severity of colitis and tissue myeloperoxidase accumulation (p < 0.001). Also, PAE at 80 mg/kg significantly inhibited labelled E. coli from translocating to distant organs, especially to MLN and liver. Additionally, PAE significantly stimulated fibroblasts proliferation (126.9%) and collagen accumulation (130.8%) for 48 h incubation. Among the partitions, ethyl acetate fraction generally had higher fibroblast viability enhanced-activity.

CONCLUSIONS

PAE can protect against ulcerative colitis and this protection is attributed to anti-inflammation and fibroblasts viability.

The implications of oxidative stress and antioxidant therapies in Inflammatory Bowel Disease: Clinical aspects and animal models

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a chronic inflammatory disorder characterized by alternating phases of clinical relapse and remission. The etiology of IBD remains largely unknown, although a combination of patient's immune response, genetics, microbiome, and environment plays an important role in disturbing intestinal homeostasis, leading to development and perpetuation of the inflammatory cascade in IBD. As chronic intestinal inflammation is associated with the formation of reactive oxygen and reactive nitrogen species (ROS and RNS), oxidative and nitrosative stress has been proposed as one of the major contributing factor in the IBD development. Substantial evidence suggests that IBD is associated with an imbalance between increased ROS and decreased antioxidant activity, which may explain, at least in part, many of the clinical pathophysiological features of both CD and UC patients. Hereby, we review the presently known oxidant and antioxidant mechanisms involved in IBD-specific events, the animal models used to determine these specific features, and also the antioxidant therapies proposed in IBD patients.

Animal models of inflammatory bowel disease: a review. Inflammopharmacology. 2014;22:219-233. [PMID: 24906689 DOI: 10.1007/s10787-014-0207-y]

Inflammatory bowel disease (IBD) represents a group of idiopathic chronic inflammatory intestinal conditions associated with various areas of the GI tract, including two types of inflammatory conditions, i.e., ulcerative colitis (UC) and Crohn's disease (CD). Both UC and CD are chronic inflammatory disorders of the intestine; in UC, inflammation starts in the rectum and generally extends proximally in a continuous manner through the entire colon. Bloody diarrhea, presence of blood and mucus mixed with stool, accompanied by lower abdominal cramping, are the characteristic symptoms of the disease. While in CD, inflammatory condition may affect any part of the GI tract from mouth to anus. It mainly causes abdominal pain, diarrhea, vomiting and weight loss. Although the basic etiology of IBD is unknown, there are several factors that may contribute to the pathogenesis of this disease, such as dysregulation of immune system or commensal bacteria, oxidative stress and inflammatory mediators. In order to understand these different etiological factors, a number of experimental models are available in the scientific research, including chemical-induced, spontaneous, genetically engineered and transgenic models. These models represent a major source of information about biological systems and are clinically relevant to the human IBD. Since there is less collective data available in one single article discussing about all these models, in this review an effort is made to study the outline of pathophysiology and various types of animal models used in the research study of IBD and other disease-related complications.

NCB-02 (standardized Curcumin preparation) protects dinitrochlorobenzene-induced colitis through down-regulation of NFκ-B and iNOS

AIM: To evaluate the efficacy and mechanism of action of NCB-02, a standardized Curcumin preparation, against 2, 4-dinitrochlorobenzene (DNCB)-induced ulcerative colitis in rats.

METHODS: Ulcerative colitis was induced in male rats by sensitizing with topical application of DNCB in acetone for 14 d and intra-colonol challenge with DNCB on day 15. A separate group of animals with vehicle treatment in similar fashion served as control group. Colitis rats were divided into different groups and treated with NCB-02 at doses of 25, 50 and 100 mg/kg b.wt p.o. for 10 d. Sulfasalazine at a dose of 100 mg/kg b.wt for 10 d served as a reference group. On day 10 after respective assigned treatment, all the animals were euthanized and the length of the colon, weight of entire colon and distal 8 cm of the colon were recorded. The distal part of the colon was immediately observed under a stereomicroscope and the degree of damage was scored. Further distal 8 cm of the colon was subject to the determination of colonic myeloperoxidase (MPO), lipid peroxidation (LPO) and alkaline phosphatase (ALP) activities. A small piece of the sample from distal colon of each animal was fixed in 10% neutral buffered formalin and embedded in paraffin wax and sectioned for immunohistochemical examination of NFκ-B and iNOS expression.

RESULTS: NCB-02 showed a dose dependent protection against DNCB-induced alteration in colon length and weight. NCB-02 treatment also showed a dose dependent protection against the elevated levels of MPO, LPO and ALP, induced by DNCB. NCB-02 demonstrated a significant effect at a dose of 100 mg/kg b.wt., which was almost equipotent to 100 mg/kg b.wt. of sulfasalazine. Treatment with sulfasalazine and curcumin at a dose of 100 mg/kg b.wt. inhibited the DNCB-induced overexpression of NFκ-B and iNOS in the colon.

CONCLUSION: Curcumin treatment ameliorates colonic damage in DNCB-induced colitic rats, an effect associated with an improvement in intestinal oxidative stress and downregulation of colonic NFκ-B and iNOS expression.

A control study on treatment of ulcerative colitis with olsalazine sodium

AIM

To study the clinical efficacy and safety of olsalazine sodium in patients with ulcerative colitis (UC).

METHODS

Forty-two chronic intermittent UC patients were randomly divided into two groups: olsalazine sodium treatment group (n = 21) and SASP group (n = 21). Clinical effects and safety were compared between the two groups.

RESULTS

The overall clinical efficacy of olsalazine sodium group (completeremission in 16 cases, improvement in 4 patients, ineffective in one case) was better than that in SASP group (complete remission in 10 cases, improvement in 4 patients, ineffective in 7 cases, P<0.05).The clinical symptoms relieve of olsalazine sodium group (complete remission in 15 cases, partly in 5 patients, ineffective in one case) was better than that in SASP group (complete remission in 10 cases, partly in 5 patients, ineffective in 6 cases, P<0.05). The colonoscopic remission of olsalazine sodium group (complete remission in 11 cases, partly in 9 patients, ineffective in one case) was better than that in SASP group (complete remission in 7 cases, partly in 8 patients, ineffective in 6 cases, P<0.05). The histologic remission of olsalazine sodium group (complete remission in 13 cases, partly in 7 patients, ineffective in one case) was better than that in SASP group (complete remission in 6 cases, partly in 10 patients, ineffective in 5 cases, P<0.05). The side effects of gastrointestinal tract in olsalazine sodium group were fewer than that of SASP group except for frequency of watery diarrhea. No other side effect was observed in olsalazine sodium group, while an elevated ALT, decreased WBC and skin eruption were observed in SASP group. Two patients relapsed in olsalazine sodium group while 8 cases relapsed in SASP group during follow-up period (from 6 months to one year).

CONCLUSION

The clinical efficacy and safety of olsalazine sodium in patients with ulcerative colitis is superior to that of SASP.

An analysis of 10218 ulcerative colitis cases in China

AIM: To analyze the characteristics of ulcerative colitis (UC) in China.

METHODS: From 1981 to 2000, a total of 10218 patients of UC reported in Chinese medical literature and including our cases diagnosed were analyzed according to the diagnostic criteria of Lennard-Jones.

RESULTS: The number of cases increased by 3.08 times over the past 10 years (2506 patients were diagnosed from 1981 to 1990 while 7512 patients were diagnosed from 1991 to 2000).Lesion range were described in 7966 patients, 5592 (70.20%) were proctosigmoiditis or proctitis, 1792( 22.50%) left-sided colitis, 582(7.30%) pancolitis. Among the 8122 patients, 2826 (34.8%) had first episode, 4272 (52.6%) had chronic relapse, 869 (10.7%) were of chronic persist type, 154 (1.9%) were of acute fulminant type. The course of the illness were described in 5867 patients, 4427(75.5%) were less than 5 years, 910 (15.5%) between 5 and 10 years, 530 (9.1%) more than 10 years. Six hundred and sixteen patients patients(6.1%) had extraintestinal manifestations.The mean age at the diagnosis was 40.7 years(range 6-80 years, and the peak ages 30-49 years). The male to female ratio was1.09. Among 270 patients diagnosed in our hospital, 36 had histories of smoking, there was no negative association between the severity of UC and smoking (P > 0.05), 21 smokers were followed up for one year, 15 of them had given up smoking when the disease were diagnosed, and one year later, 7 patients relapsed, another 6 patients continued smoking, and one year later, 2 patients relapsed. Among 270 UC patients diagnosed in our hospital, 4 patients(1.48%) from 2 families had familial history of UC. Treatment was mentioned in 6859 patients, only 5-ASA and/or corticosteroid only in 1276 patients(18.6%), only Chinese herbs in 1377 patients(20.1%), combined Chinese and western medicine in 4056 patients(59.1%), surgery was performed in 87 patients(1.3%), other treatments in 63 patients(0.9%).

CONCLUSIONS: In China, number of UC patients increased significantly in the past 10 years. Lesions are commonly located to left side colon. The course is short with rare extraintestinal manifestations. The age of onset is relatively high. Males and females are nearly equally affected. No negative relation was found between smoking and severity of the disease. Familial relatives are rarely involved Traditional Chinese medicine(TCM) is widely used in the treatment of UC.