Green Tea Polyphenols and Sulfasalazine have Parallel Anti-Inflammatory Properties in Colitis Models

Comparative Evaluation between Sulfasalazine Alone and in Combination with Herbal Medicine on DSS-Induced Ulcerative Colitis Mice

The present study aimed to investigate the comparative evaluation of pharmacological efficacy between sulfasalazine alone and sulfasalazine in combination with herbal medicine on dextran sodium sulfate- (DSS-) induced UC in mice. Balb/c mice received 5% DSS in drinking water for 7 days to induce colitis. Animals were divided into five groups (n = 9): Group I (normal group), Group II (DSS control group), Group III (DSS + sulfasalazine (30 mg/kg)), Group IV (DSS + sulfasalazine (60 mg/kg)), and Group V (DSS + sulfasalazine (30 mg/kg) + Cinnamomi Cortex and Bupleuri Radix mixture (30 mg/kg) (SCB)). Colonic pathological changes were analyzed using hematoxyline/eosin staining. The antioxidant, inflammatory, and apoptotic protein levels were determined using western blotting. SCB supplementation, as well as sulfasalazine, suppressed colonic length and mucosal inflammatory infiltration. In addition, SCB treatment significantly reduced the expression of proinflammatory signaling molecules through suppression of both mitogen-activated protein kinases (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways and prevented the apoptosis of the colon. Moreover, SCB administration significantly led to the upregulation of antioxidant enzymes including SOD and catalase. Taken together, SCB treatment might offer a better treatment for human UC than sulfasalazine alone or may be useful as an alternative therapeutic strategy against UC, without any evidence of side effects.

Downregulation of iNOS and elevation of cAMP mediate the anti-inflammatory effect of glabridin in rats with ulcerative colitis

BACKGROUND

Alternative medicine is widely accepted by public and becoming an attractive approach for treatment of various diseases. Glabridin (Gla), a major flavonoid present in licorice root, was reported to have antioxidant and anti-inflammatory properties.

OBJECTIVE

The study aimed to investigate the possible protective role of Gla against dextran sulphate sodium (DSS)-induced ulcerative colitis (UC) in rats and to clarify the molecular mechanisms underlying Gla function.

METHODS

Forty male Wistar rats were divided into control, colitis group (rats received 5% DSS in drinking water for 7 days), Gla group (50 mg/kg, orally, once daily), and sulfasalazine (SLZ) group (500 mg/kg, orally, once daily). Each of Gla and SLZ was administered 1 week ahead of DSS and parallel with its administration.

RESULTS

Gla ameliorated the inflammatory alterations induced by DSS. Gla group showed a reduction in colon concentration of tumor necrosis factor-alpha (TNF-α) and a decreased colon myeloperoxidase activity (MPO). Gla treatment downregulated inducible nitric oxide synthase (iNOS) gene expression in rat colon with a decreased content of nitric oxide (NO). Gla also increased cyclic AMP (cAMP) concentration in rat colon compared to colitis group. Such findings were comparable to or even better than those obtained by SLZ treatment. The histological features of UC such as ulceration and inflammatory cell infiltrations were improved in rat group treated by Gla.

CONCLUSION

Gla proved a potent anti-inflammatory role in UC through different mechanisms and, being a natural product, it could be safely used as a protective measure in inflammatory bowel diseases.

Chronic Inflammatory Diseases and Green Tea Polyphenols

Chronic inflammatory diseases affect millions of people globally and the incidence rate is on the rise. While inflammation contributes to the tissue healing process, chronic inflammation can lead to life-long debilitation and loss of tissue function and organ failure. Chronic inflammatory diseases include hepatic, gastrointestinal and neurodegenerative complications which can lead to malignancy. Despite the millennial advancements in diagnostic and therapeutic modalities, there remains no effective cure for patients who suffer from inflammatory diseases. Therefore, patients seek alternatives and complementary agents as adjunct therapies to relieve symptoms and possibly to prevent consequences of inflammation. It is well known that green tea polyphenols (GrTPs) are potent antioxidants with important roles in regulating vital signaling pathways. These comprise transcription nuclear factor-kappa B mediated I kappa B kinase complex pathways, programmed cell death pathways like caspases and B-cell lymphoma-2 and intervention with the surge of inflammatory markers like cytokines and production ofcyclooxygenase-2. This paper concisely reviews relevant investigations regarding protective effects of GrTPs and some reported adverse effects, as well as possible applications for GrTPs in the treatment of chronic and inflammatory complications.

Mycobacterium avium subsp. paratuberculosis and associated risk factors for inflammatory bowel disease in Iranian patients

Background

Inflammatory bowel disease (IBD) is described as a relapsing condition with high morbidity and uncertain complex pathogenesis. The association of Mycobacterium avium ssp. paratuberculosis (MAP) with Crohn’s disease (CD) in human has been debated for decades, however there is no confirmed data to verify such relations in Iran. The aim of this study was to investigate risk factors and a possible role of MAP in Iranian patients with CD.

Methods

Anti-MAP antibodies were detected in serum of IBD patients and subjects without IBD (nIBD) through ELISA; MAP DNA and viable MAP cells were identified in patients’ biopsies through nested PCR and direct culture methods, respectively. Principal component analysis (PCA) was used to investigate the risk factors in relation to IBD and MAP infection.

Results

Positivity for IS900 PCR was detected in 64% (n = 18) of CD, 33% (n = 10) of ulcerative colitis (UC) and 9.7% (n = 6) of nIBD samples. Live MAP cells were isolated from biopsies of 2 CD patients only. Among 28 patients with CD, 46% (n = 13) and 39% (n = 11) were positive for antibodies against MAP3865c_133–141 and MAP3865c_125–133 peptides, respectively, whereas much lower seroreactivity was detected in UC subjects accounting for 3% (n = 1) for MAP3865c_133–141 and 16.7% (n = 5) for MAP3865c_125–133. A high immune reactivity to MAP epitopes among CD patients was positively correlated with consumption of fast food meals and IBD familiarity. For both CD and UC, breastfeeding period and consumption of fruit/vegetables presented negative correlation with the presence of anti-MAP antibodies.

Conclusions

This study provided evidences that high prevalence of MAP DNA and anti-MAP antibodies in CD patients is significantly associated with the development of CD. Despite the role of several factors contributing to IBD, the presence of MAP DNA and anti-MAP antibodies in Iranian CD patients highlights a possible transmission of MAP from animal-derived products to humans.

Co-operative suppression of inflammatory responses in human dendritic cells by plant proanthocyanidins and products from the parasitic nematode Trichuris suis

Interactions between dendritic cells (DCs) and environmental, dietary and pathogen antigens play a key role in immune homeostasis and regulation of inflammation. Dietary polyphenols such as proanthocyanidins (PAC) may reduce inflammation, and we therefore hypothesized that PAC may suppress lipopolysaccharide (LPS) -induced responses in human DCs and subsequent T helper type 1 (Th1) -type responses in naive T cells. Moreover, we proposed that, because DCs are likely to be exposed to multiple stimuli, the activity of PAC may synergise with other bioactive molecules that have anti-inflammatory activity, e.g. soluble products from the helminth parasite Trichuris suis (TsSP). We show that PAC are endocytosed by monocyte-derived DCs and selectively induce CD86 expression. Subsequently, PAC suppress the LPS-induced secretion of interleukin-6 (IL-6) and IL-12p70, while enhancing secretion of IL-10. Incubation of DCs with PAC did not affect lymphocyte proliferation; however, subsequent interferon-γ production was markedly suppressed, while IL-4 production was unaffected. The activity of PAC was confined to oligomers (degree of polymerization ≥ 4). Co-pulsing DCs with TsSP and PAC synergistically reduced secretion of tumour necrosis factor-α, IL-6 and IL-12p70 while increasing IL-10 secretion. Moreover, both TsSP and PAC alone induced Th2-associated OX40L expression in DCs, and together synergized to up-regulate OX40L. These data suggest that PAC induce an anti-inflammatory phenotype in human DCs that selectively down-regulates Th1 response in naive T cells, and that they also act cooperatively with TsSP. Our results indicate a novel interaction between dietary compounds and parasite products to influence immune function, and may suggest that combinations of PAC and TsSP can have therapeutic potential for inflammatory disorders.

Anti-inflammatory protection afforded by cyanidin-3-glucoside and resveratrol in human intestinal cells via Nrf2 and PPAR-γ: Comparison with 5-aminosalicylic acid

This study investigated the involvement of nuclear factor erythroid 2 (Nrf2) and peroxisome proliferator-activated receptor-gamma (PPAR-γ) pathways in the protection afforded by two polyphenols abundant in diet, cyanidin-3-glucoside and resveratrol, against cytokine-induced inflammation and oxidative insult in HT-29 intestinal cells, in comparison with the drug 5-aminosalicylic acid (5-ASA). Our data show for the first time that in cytokine-challenged cells, cyanidin-3-glucoside and resveratrol induced Nrf2 activation, increased hemoxygenase-1 and glutamate cysteine ligase mRNA expression, enhanced reduced glutathione to oxidized glutathione ratio and inhibited reactive species production, at much lower concentrations than 5-ASA. Unlike cyanidin-3-glucoside, resveratrol and 5-ASA also increased nuclear levels of PPAR-γ in cytokine-stimulated cells. In conclusion, both polyphenols might be interesting as nutraceuticals, giving complementary benefits to conventional drugs against intestinal inflammation, typically present in patients with inflammatory bowel disease.

Use of complementary and alternative medicine in Swedish patients with inflammatory bowel disease: a controlled study

BACKGROUND

There is an increasing interest in complementary and alternative medicine (CAM) in patients with chronic diseases, including those with inflammatory bowel disease (IBD). Patients may turn to CAM when conventional therapies are inadequate or associated with side effects for symptomatic relief or to regain control over their disease. The objectives were to explore CAM use and perceived effects in IBD patients in comparison with a control group.

METHODS

A cross-sectional, multicenter, controlled study was carried out. IBD patients were invited from 12 IBD clinics in Sweden. Controls were selected randomly from a residence registry. A study-specific questionnaire was used for data collection.

RESULTS

Overall, 48.3% of patients with IBD had used some kind of CAM during the past year compared with 53.5% in controls (P=0.025, adjusted for age, sex, geographic residence, and diet). The most frequently used CAM among IBD patients was massage (21.3%), versus controls (31.4%) (adjusted P=0.0003). The second most used CAM was natural products, 18.7% in IBD patients versus 22.3% of the controls (unadjusted P=0.018). In all, 83.1% of the patients experienced positive effects from CAM and 14.4% experienced negative effects.

CONCLUSION

Overall, 48.3% of Swedish IBD patients used some kind of CAM and controls used CAM significantly more. Natural products were used by one-fifth of the patients and even more by controls. This is notable from a patient safety perspective considering the possible risks of interactions with conventional medication. In all, 40% of the patients reported adverse events from conventional medicine. Patients experienced predominantly positive effects from CAM, and so did controls.

Bioactivity of Polyphenols: Preventive and Adjuvant Strategies toward Reducing Inflammatory Bowel Diseases-Promises, Perspectives, and Pitfalls

Inflammatory bowel diseases (IBDs) are characterized by autoimmune and inflammation-related complications of the large intestine (ulcerative colitis) and additional parts of the digestive tract (Crohn's disease). Complications include pain, diarrhoea, chronic inflammation, and cancer. IBD prevalence has increased during the past decades, especially in Westernized countries, being as high as 1%. As prognosis is poor and medication often ineffective or causing side effects, additional preventive/adjuvant strategies are sought. A possible approach is via diets rich in protective constituents. Polyphenols, the most abundant phytochemicals, have been associated with anti-inflammatory, antioxidant, immunomodulatory, and apoptotic properties. Locally reducing oxidative stress, they can further act on cellular targets, altering gene expression related to inflammation, including NF-κB, Nrf-2, Jak/STAT, and MAPKs, suppressing downstream cytokine formation (e.g., IL-8, IL-1β, and TNF-α), and boosting the bodies' own antioxidant status (HO-1, SOD, and GPx). Moreover, they may promote, as prebiotics, healthy microbiota (e.g., Bifidobacteria, Akkermansia), short-chain fatty acid formation, and reduced gut permeability/improved tight junction stability. However, potential adverse effects such as acting as prooxidants, or perturbations of efflux transporters and phase I/II metabolizing enzymes, with increased uptake of undesired xenobiotics, should also be considered. In this review, we summarize current knowledge around preventive and arbitrary actions of polyphenols targeting IBD.

(-)-Epigallocatechin-3-gallate decreases colonic inflammation and permeability in a mouse model of colitis, but reduces macronutrient digestion and exacerbates weight loss

SCOPE

(-)-Epigallocatechin-3-gallate (EGCG) has been reported to have putative health effects including the prevention of inflammation and obesity. Historically, polyphenols have been regarded as antinutritionals and while such effects may be beneficial in obese subjects, they may be deleterious in nutritionally compromised individuals.

METHODS AND RESULTS

We examined the effect of EGCG in the dextran sulfate sodium (DSS)-treated mouse model of ulcerative colitis. Following induction of colitis, mice were treated with EGCG (3.2 mg/g) as the sole source of drinking fluid for 3 days. EGCG treatment mitigated DSS-induced colon shortening and spleen enlargement. EGCG also decreased colonic protein levels of IL-1β, IL-6, and tumor necrosis factor-α, as well as colonic lipid peroxides compared to DSS-treated controls. We observed that EGCG reduced DSS-induced gastrointestinal permeability. These beneficial effects were offset by enhanced body weight loss in EGCG-treated mice compared to DSS-treated controls. These effects were related to decreased protein and lipid digestion in EGCG-treated mice compared to DSS-treated controls.

CONCLUSIONS

Our results suggest that although EGCG may exert anti-inflammatory effects, its ability to modulate macronutrient digestion may represent a dose-limiting adverse effect that must be considered in the context of its use for treating inflammatory bowel disease.

Multiorgan chronic inflammatory hepatobiliary pancreatic murine model deficient in tumor necrosis factor receptors 1 and 2

AIM: To provoke persistent/chronic multiorgan inflammatory response and to contribute to stones formation followed by fibrosis in hepatobiliary and pancreatic tissues.

METHODS: Tumor necrosis factor receptors 1 and 2 (TNFR1/R2) deficient mice reared in-house were given dibutyltin dichloride (DBTC) twice within 10 d by oral gavage delivery. Sham control animals received vehicle treatment and naïve animals remained untreated throughout the study. Animals were monitored daily for symptoms of pain and discomfort. The abdominal and hindpaw hypersensitivity were assessed with von Frey microfilaments. Exploratory behaviors were recorded at the baseline, after initiation of treatment, and before study termination. Histopathological changes were examined postmortem in tissues. Collagen accumulation and fibrosis were confirmed with Sirius Red staining.

RESULTS: Animals lost weight after oral administration of DBTC and developed persistent inflammatory abdominal and hindpaw hypersensitivity compared to sham-treated controls (P < 0.0001). These pain related secondary mechanical hypersensitivity responses increased more than 2-fold in DBTC-treated animals. The drastically diminished rearing and grooming rates persisted after DBTC administration throughout the study. Gross as well as micropathology at one month confirmed that animals treated with DBTC developed chronic hepatobiliary injuries evidenced with activation of stellate cells, multifocal necrosis, fatty degeneration of hepatocytes, periportal infiltration of inflammatory cells, and prominent biliary ductal dilation. The severity of hepatitis was scored 3.7 ± 0.2 (severe) in DBTC-treated animals vs score 0 (normal) in sham-treated animals. Fibrotic thickening was extensive around portal ducts, in hepatic parenchyma as well as in lobular pancreatic structures and confirmed with Sirius Red histopathology. In addition, pancreatic microarchitecture was presented with distortion of islets, and parenchyma, infiltration of inflammatory cells, degeneration, vacuolization, and necrosis of acinar cells and distention of pancreatic ducts. Extent of pancreatic damage and pancreatitis were scored 3.6 ± 0.4 (severe) for DBTC-treated in contrast to score 0 (normal) in sham-treated animals. The gall bladder became expanded with ductal distention, and occasional bile stones were detected along with microscopic hepatic lesions. DBTC-treated animals developed splenic hypertrophy with increased weight and length (P < 0.01) along with thymic atrophy (P < 0.001). Finally, colitic lesions and colitis were prominent in DBTC-treated animals and scored 3.4 ± 0.3 (moderately severe) vs 0 (normal) for the sham-treated animals.

CONCLUSION: This is the first report of chronic inflammatory multiorgan hepatobiliary pancreatitis, along with fibrosis and calculi formation induced reliably utilizing oral DBTC administration in TNFR1/R2 deficient mice.

Flavonoids in Inflammatory Bowel Disease: A Review

Inflammatory bowel disease (IBD) is characterized by chronic inflammation of the intestine that compromises the patients’ life quality and requires sustained pharmacological and surgical treatments. Since their etiology is not completely understood, non-fully-efficient drugs have been developed and those that have shown effectiveness are not devoid of quite important adverse effects that impair their long-term use. In this regard, a growing body of evidence confirms the health benefits of flavonoids. Flavonoids are compounds with low molecular weight that are widely distributed throughout the vegetable kingdom, including in edible plants. They may be of great utility in conditions of acute or chronic intestinal inflammation through different mechanisms including protection against oxidative stress, and preservation of epithelial barrier function and immunomodulatory properties in the gut. In this review we have revised the main flavonoid classes that have been assessed in different experimental models of colitis as well as the proposed mechanisms that support their beneficial effects.

Epigallocatechin-3-Gallate Inhibition of Myeloperoxidase and Its Counter-Regulation by Dietary Iron and Lipocalin 2 in Murine Model of Gut Inflammation

Green tea-derived polyphenol (-)-epigallocatechin-3-gallate (EGCG) has been extensively studied for its antioxidant and anti-inflammatory properties in models of inflammatory bowel disease, yet the underlying molecular mechanism is not completely understood. Herein, we demonstrate that EGCG can potently inhibit the proinflammatory enzyme myeloperoxidase in vitro in a dose-dependent manner over a range of physiologic temperatures and pH values. The ability of EGCG to mediate its inhibitory activity is counter-regulated by the presence of iron and lipocalin 2. Spectral analysis indicated that EGCG prevents the peroxidase-catalyzed reaction by reverting the reactive peroxidase heme (compound I:oxoiron) back to its native inactive ferric state, possibly via the exchange of electrons. Further, administration of EGCG to dextran sodium sulfate-induced colitic mice significantly reduced the colonic myeloperoxidase activity and alleviated proinflammatory mediators associated with gut inflammation. However, the efficacy of EGCG against gut inflammation is diminished when orally coadministered with iron. These findings indicate that the ability of EGCG to inhibit myeloperoxidase activity is one of the mechanisms by which it exerts mucoprotective effects and that counter-regulatory factors such as dietary iron and luminal lipocalin 2 should be taken into consideration for optimizing clinical management strategies for inflammatory bowel disease with the use of EGCG treatment.

A review of the efficacy of dietary polyphenols in experimental models of inflammatory bowel diseases

Crohn's disease and ulcerative colitis presently have no cure and are treated with anti-inflammatory drugs or monoclonal antibodies targeting pro-inflammatory cytokines. A variety of rodent models have been used to model chronic and acute colitis. Dietary polyphenols in foods and botanicals are of considerable interest for prevention and treatment of colitis. Many dietary polyphenols have been utilized for prevention of colitis in rodent models. Berries, green tea polyphenols, curcumin, and stilbenes have been the most extensively tested polyphenols in rodent models of colitis. The majority of polyphenols tested have inhibited colitis in rodents, but increasing doses of EGCG and green tea, isoflavones, flaxseed, and α-mangostin have exacerbated colitis. Few studies have examined combination of polyphenols or other bioactives for inhibition of colitis. Translating polyphenol doses used in rodent models of colitis to human equivalent doses reveals that supplemental doses are most likely required to inhibit colitis from a single polyphenol treatment. The ability to translate polyphenol treatments in rodent models is likely to be limited by species differences in xenobiotic metabolism and microbiota. Given these limitations, data from polyphenols in rodent models suggests merit for pursuing additional clinical studies for prevention of colitis.

Advances in nutritional therapy in inflammatory bowel diseases: Review

Inflammatory bowel diseases (IBD), including ulcerative colitis and Crohn's disease are chronic, life-long, and relapsing diseases of the gastrointestinal tract. Currently, there are no complete cure possibilities, but combined pharmacological and nutritional therapy may induce remission of the disease. Malnutrition and specific nutritional deficiencies are frequent among IBD patients, so the majority of them need nutritional treatment, which not only improves the state of nutrition of the patients but has strong anti-inflammatory activity as well. Moreover, some nutrients, from early stages of life are suspected as triggering factors in the etiopathogenesis of IBD. Both parenteral and enteral nutrition is used in IBD therapy, but their practical utility in different populations and in different countries is not clearly established, and there are sometimes conflicting theories concerning the role of nutrition in IBD. This review presents the actual data from research studies on the influence of nutrition on the etiopathogenesis of IBD and the latest findings regarding its mechanisms of action. The use of both parenteral and enteral nutrition as therapeutic methods in induction and maintenance therapy in IBD treatment is also extensively discussed. Comparison of the latest research data, scientific theories concerning the role of nutrition in IBD, and different opinions about them are also presented and discussed. Additionally, some potential future perspectives for nutritional therapy are highlighted.

Antioxidant therapy for treatment of inflammatory bowel disease: Does it work?

Oxidative stress (OS) is considered as one of the etiologic factors involved in several signals and symptoms of inflammatory bowel diseases (IBD) that include diarrhea, toxic megacolon and abdominal pain. This systematic review discusses approaches, challenges and perspectives into the use of nontraditional antioxidant therapy on IBD, including natural and synthetic compounds in both human and animal models. One hundred and thirty four papers were identified, of which only four were evaluated in humans. Some of the challenges identified in this review can shed light on this fact: lack of standardization of OS biomarkers, absence of safety data and clinical trials for the chemicals and biological molecules, as well as the fact that most of the compounds were not repeatedly tested in several situations, including acute and chronic colitis. This review hopes to stimulate researchers to become more involved in this fruitful area, to warrant investigation of novel, alternative and efficacious antioxidant-based therapies.

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Major biomarkers used for evaluation of antioxidant therapy were MPO, TBARS/MDA and glutathione levels.

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Challenges were identified for the yet poor use of antioxidant therapy in IBD.

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This review stimulates the investigation of alternative and efficacious antioxidant therapies.

Metabolic and Microbial Modulation of the Large Intestine Ecosystem by Non-Absorbed Diet Phenolic Compounds: A Review

Phenolic compounds represent a diverse group of phytochemicals whose intake is associated with a wide spectrum of health benefits. As consequence of their low bioavailability, most of them reach the large intestine where, mediated by the action of local microbiota, a series of related microbial metabolites are accumulated. In the present review, gut microbial transformations of non-absorbed phenolic compounds are summarized. Several studies have reached a general consensus that unbalanced diets are associated with undesirable changes in gut metabolism that could be detrimental to intestinal health. In terms of explaining the possible effects of non-absorbed phenolic compounds, we have also gathered information regarded their influence on the local metabolism. For this purpose, a number of issues are discussed. Firstly, we consider the possible implications of phenolic compounds in the metabolism of colonic products, such as short chain fatty acids (SCFA), sterols (cholesterol and bile acids), and microbial products of non-absorbed proteins. Due to their being recognized as affective antioxidant and anti-inflammatory agents, the ability of phenolic compounds to counteract or suppress pro-oxidant and/or pro-inflammatory responses, triggered by bowel diseases, is also presented. The modulation of gut microbiota through dietetic maneuvers including phenolic compounds is also commented on. Although the available data seems to assume positive effects in terms of gut health protection, it is still insufficient for solid conclusions to be extracted, basically due to the lack of human trials to confirm the results obtained by the in vitro and animal studies. We consider that more emphasis should be focused on the study of phenolic compounds, particularly in their microbial metabolites, and their power to influence different aspects of gut health.

Favourable effects of grape seed extract on intestinal epithelial differentiation and barrier function in IL10-deficient mice

The impairment in the rate of cell proliferation and differentiation leads to a negative consequence on the renewal of the intestinal epithelium, which is the aetiological factor of a number of digestive diseases. Grape seed extract (GSE), a rich source of proanthocyanidins, is known for its beneficial health effects. The present study evaluated the beneficial effects of GSE on colonic cell differentiation and barrier function in IL10-deficient mice. Female mice aged 6 weeks were randomised into two groups and given drinking-water containing 0 or 0.1 % GSE (w/v) for 12 weeks. GSE supplementation decreased serum TNF-α level and intestinal permeability, and increased the colonic goblet cell density that was associated with increased mRNA expression of mucin (Muc)-2. Immunohistochemical analyses showed lower accumulation of β-catenin in the crypts of colon tissues of the GSE-supplemented mice, which was associated with a decreased mRNA expression of two downstream effectors of Wingless and Int (Wnt)/catenin signalling, myelocytomatosis oncogene protein (Myc) and cyclin D1 (Ccnd1). Consistently, GSE supplementation decreased the number of colonic proliferating cell nuclear antigen-positive cells, a well-known cell proliferation marker, and a weakened extracellular signal-regulated kinases 1 and 2 (ERK1/2) signalling. In summary, these data indicate that supplementation of 0.1 % GSE for 12 weeks improved gut barrier function and colonic cell differentiation in the IL10-deficient mice probably via inhibiting Wnt/β-catenin pathway.

The Sasa quelpaertensis Leaf Extract Inhibits the Dextran Sulfate Sodium-induced Mouse Colitis Through Modulation of Antioxidant Enzyme Expression

Background:

Oxidative stress plays an important role in the pathogenesis of inflammatory bowel disease. The objective of this study is to investigate the protective effect of Sasa quelpaertensis leaf extract (SQE) against oxidative stress in mice with dextran sulfate sodium (DSS)-induced colitis.

Methods:

Mice were treated with SQE (100 mg/kg or 300 mg/kg body weight) by gavage in advance two weeks before inflammation was induced. Then, the mice were administered with 2.5% DSS in drinking water for 7 days and normal drinking water for 7 days between two DSS treatment. Disease activity index values, gut motility, and severity of the resulting oxidative DNA damage were analyzed. The antioxidant effect of SQE was evaluated by measuring malondialdehyde (MDA) and superoxide dismutase (SOD) activity in plasma samples. Catalase activity and expressions levels of glutathione peroxidase 1 (Gpx1), SOD1, and SOD2 were also detected in colon tissues.

Results:

Administration of SQE significantly reduced the severity of DSS-induced colitis compared to the control (Ctrl) group. Levels of 8-oxo-dG, an oxidative DNA damage marker, were significantly lower in the SQE group compared to the untreated DSS Ctrl group. In the SQE (300 mg/kg) group, MDA levels were significantly lower, while SOD and catalase activity levels in the plasma samples were significantly higher compared with the DSS Ctrl group. The expression levels of the antioxidant enzymes, SOD2 and Gpx1, were significantly higher, while the levels of SOD 1 expression were lower, in the colon tissues of the DSS Ctrl group compared with those of the Ctrl group. In contrast, administration of SQE significantly down-regulated SOD2 and Gpx1 expressions and up-regulated SOD1 expression.

Conclusions:

These results indicate that SQE efficiently suppresses oxidative stress in DSS-induced colitis in mice, and its action is associated with the regulation of antioxidant enzymes.

Environmental risk factors in inflammatory bowel disease: a population-based case-control study in Asia-Pacific

OBJECTIVE

The rising incidence of inflammatory bowel disease in Asia supports the importance of environmental risk factors in disease aetiology. This prospective population-based case-control study in Asia-Pacific examined risk factors prior to patients developing IBD.

DESIGN

442 incident cases (186 Crohn's disease (CD); 256 UC; 374 Asians) diagnosed between 2011 and 2013 from eight countries in Asia and Australia and 940 controls (frequency-matched by sex, age and geographical location; 789 Asians) completed an environmental factor questionnaire at diagnosis. Unconditional logistic regression models were used to estimate adjusted ORs (aOR) and 95% CIs.

RESULTS

In multivariate model, being breast fed >12 months (aOR 0.10; 95% CI 0.04 to 0.30), antibiotic use (aOR 0.19; 0.07 to 0.52), having dogs (aOR 0.54; 0.35 to 0.83), daily tea consumption (aOR 0.62; 0.43 to 0.91) and daily physical activity (aOR 0.58; 0.35 to 0.96) decreased the odds for CD in Asians. In UC, being breast fed >12 months (aOR 0.16; 0.08 to 0.31), antibiotic use (aOR 0.48; 0.27 to 0.87), daily tea (aOR 0.63; 0.46 to 0.86) or coffee consumption (aOR 0.51; 0.36 to 0.72), presence of hot water tap (aOR 0.65; 0.46 to 0.91) and flush toilet in childhood (aOR 0.71; 0.51 to 0.98) were protective for UC development whereas ex-smoking (aOR 2.02; 1.22 to 3.35) increased the risk of UC.

CONCLUSIONS

This first population-based study of IBD risk factors in Asia-Pacific supports the importance of childhood immunological, hygiene and dietary factors in the development of IBD, suggesting that markers of altered intestinal microbiota may modulate risk of IBD later in life.

Surgical Correction of Rectal Prolapse in Laboratory Mice (Mus musculus)

Rectal prolapse is a common clinical problem in laboratory mice. This condition may occur spontaneously, develop after genetic manipulations, result from infections with pathogens such as Citrobacter species, or arise secondary to experimental design such as colitis models. The current standard of care at our institution is limited to monitoring mice until tissue becomes ulcerated or necrotic; this strategy often leads to premature euthanasia of valuable animals prior to the study endpoint. Surgical correction of rectal prolapse is performed routinely and with minimal complications in larger species by using manual reduction with placement of a pursestring suture. In this report, we investigated whether the use of a pursestring suture was an effective treatment for mice with rectal prolapse. The procedure includes anesthetizing mice with isoflurane, manually reducing prolapsed tissue, and placing a pursestring suture of 4-0 polydioxanone. We have performed this procedure successfully in 12 mice. Complications included self-trauma, fecal impaction due to lack of defecation, and mutilation of the surgical site by cage mates. Singly housing mice for 7 d postoperatively, applying multimodal analgesia, and releasing the pursestring when indicated eliminated these complications. The surgical repair of rectal prolapses in mice is a minimally invasive procedure that resolves the clinical symptoms of affected animals and reduces the number of mice that are euthanized prematurely prior to the study endpoint.

Diet in the pathogenesis and treatment of inflammatory bowel diseases

Some of the most common symptoms of the inflammatory bowel diseases (IBD, which include ulcerative colitis and Crohn's disease) are abdominal pain, diarrhea, and weight loss. It is therefore not surprising that clinicians and patients have wondered whether dietary patterns influence the onset or course of IBD. The question of what to eat is among the most commonly asked by patients, and among the most difficult to answer for clinicians. There are substantial variations in dietary behaviors of patients and recommendations for them, although clinicians do not routinely endorse specific diets for patients with IBD. Dietary clinical trials have been limited by their inability to include a placebo control, contamination of study groups, and inclusion of patients receiving medical therapies. Additional challenges include accuracy of information on dietary intake, complex interactions between foods consumed, and differences in food metabolism among individuals. We review the roles of diet in the etiology and management of IBD based on plausible mechanisms and clinical evidence. Researchers have learned much about the effects of diet on the mucosal immune system, epithelial function, and the intestinal microbiome; these findings could have significant practical implications. Controlled studies of patients receiving enteral nutrition and observations made from patients on exclusion diets have shown that components of whole foods can have deleterious effects for patients with IBD. Additionally, studies in animal models suggested that certain nutrients can reduce intestinal inflammation. In the future, engineered diets that restrict deleterious components but supplement beneficial nutrients could be used to modify the luminal intestinal environment of patients with IBD; these might be used alone or in combination with immunosuppressive agents, or as salvage therapy for patients who do not respond or lose responsiveness to medical therapies. Stricter diets might be required to induce remission, and more sustainable exclusion diets could be used to maintain long-term remission.

Protective effects of Semen Crotonis Pulveratum on trinitrobenzene sulphonic acid-induced colitis in rats and H₂O₂-induced intestinal cell apoptosis in vitro

Ulcerative colitis (UC) is a chronic inflammatory bowel disease. Semen Crotonis Pulveratum (SCP) has been used as a traditional medicine for the treatment of UC. However, its molecular mechanisms of action have not yet been elucidated. In the present study, we aimed to investigate the preliminary mechanisms of the role of SCP on trinitrobenzene sulphonic acid (TNBS)-induced UC in rats and hydrogen peroxide (H2O2)-induced intestinal cell apoptosis in vitro. Wistar rats (n=9 per group) were randomly divided into 4 groups: the normal control group, the UC group, the UC + SCP group and the UC + sulfasalazine group as a positive control. The proportion of CD4+CD25+ T cells and CD4+CD25+Foxp3+ Tregs, and the expression levels of interleukin (IL)-6 and IL-10 in the peripheral blood, as well as the expression levels of cyclooxygenase-2 (COX-2) and intercellular adhesion molecule-1 (ICAM-1) in the colon tissues were determined by flow cytometry, ELISA and immunohistochemical staining, respectively. Rat intestinal epithelial (IEC-6) cell apoptosis induced by H2O2 was determined by TUNEL assay, flow cytometry using Annexin V/propidium iodide (PI) staining and western blot analysis of caspase-3 activation, respectively. Significantly higher proportions of circulating CD4+CD25+ T cells and CD4+CD25+Foxp3+ Tregs were present in the UC + SCP group compared with the UC group. A significantly decreased expression of IL-6 and an increased expression of IL-10 were also observed in the UC + SCP group compared with UC group. SCP significantly reduced the UC-induced increase in the expression of COX-2 and ICAM-1 in the colon tissues. SCP inhibited cell apoptosis and caspase-3 activation induced by H2O2 in the ICE-6 cells. Our data thus indicate that SCP inhibits inflammation in UC by increasing the proportion of circulating Tregs, altering cytokine production and decreasing COX-2 and ICAM-1 expression. In addition it protects against H2O2-induced intestinal cell apoptosis in vitro.

The relationship between phenolic compounds from diet and microbiota: impact on human health

The human intestinal tract is home to a complex microbial community called microbiota.

Marine hydroquinone zonarol prevents inflammation and apoptosis in dextran sulfate sodium-induced mice ulcerative colitis

BACKGROUND AND AIM

We previously identified an anti-inflammatory compound, zonarol, a hydroquinone isolated from the brown algae Dictyopteris undulata as a marine natural product. To ascertain the in vivo functions of zonarol, we examined the pharmacological effects of zonarol administration on dextran sulfate sodium (DSS)-induced inflammation in a mouse model of ulcerative colitis (UC). Our goal is to establish a safe and effective cure for inflammatory bowel disease (IBD) using zonarol.

METHODS AND RESULTS

We subjected Slc:ICR mice to the administration of 2% DSS in drinking water for 14 days. At the same time, 5-aminosalicylic acid (5-ASA) at a dose of 50 mg/kg (positive control) and zonarol at doses of 10 and 20 mg/kg, were given orally once a day. DSS-treated animals developed symptoms similar to those of human UC, such as severe bloody diarrhea, which were evaluated by the disease activity index (DAI). Treatment with 20 mg/kg of zonarol, as well as 5-ASA, significantly suppressed the DAI score, and also led to a reduced colonic ulcer length and/or mucosal inflammatory infiltration by various immune cells, especially macrophages. Zonarol treatment significantly reduced the expression of pro-inflammatory signaling molecules, and prevented the apoptosis of intestinal epithelial cells. Finally, zonarol protected against in vitro lipopolysaccharide (LPS)-induced activation in the RAW264.7 mouse macrophage cell line.

CONCLUSIONS

This is the first report that a marine bioproduct protects against experimental UC via the inhibition of both inflammation and apoptosis, very similar to the standard-of-care sulfasalazine, a well-known prodrug that releases 5-ASA. We believe that the oral administration of zonarol might offer a better treatment for human IBDs than 5-ASA, or may be useful as an alternative/additive therapeutic strategy against UC, without any evidence of side effects.

Dietary agents and phytochemicals in the prevention and treatment of experimental ulcerative colitis

Inflammatory bowel diseases (IBDs), consisting mainly of ulcerative colitis (UC) and Crohn's disease (CD), are important immune-mediated diseases of the gastrointestinal tract. The etiology of the disease includes environmental and genetic factors. Its management presents a constant challenge for gastroenterologists and conventional surgeon. 5-Amninosalicylates, antibiotics, steroids, and immune modulators have been used to reduce the symptoms and for maintenance of remission. Unfortunately, long-term usage of these agents has been found to lead to severe toxicities, which are deterrent to the users. Pre-clinical studies carried out in the recent past have shown that certain dietary agents, spices, oils, and dietary phytochemicals that are consumed regularly possess beneficial effects in preventing/ameliorating UC. For the first time, this review addresses the use of these dietary agents and spices in the treatment and prevention of IBD and also emphasizes on the mechanisms responsible for their effects.

Sasa quelpaertensis leaf extract suppresses dextran sulfate sodium-induced colitis in mice by inhibiting the proinflammatory mediators and mitogen-activated protein kinase phosphorylation

Sasa quelpaertensis leaves exert anti-inflammatory and anticarcinogenic effects, although it remains unclear whether these leaves can suppress inflammation-related intestinal diseases. This study hypothesized that Sasa quelpaertensis leaf extract (SQE) exerts a protective effect against inflammation in a dextran sulfate sodium (DSS)-induced colitis mouse model. Therefore, colon tissues of DSS-induced colitis mice that were treated with SQE were assayed for levels of proinflammatory markers, mitogen-activated protein kinase signaling, and activation of nuclear factor κB. For this purpose, mice were pretreated with SQE (100 mg/kg or 300 mg/kg body weight) by gavage for a 2-week period. Mice then received either SQE or sulfasalazine (100 mg/kg body weight) with 2.5% DSS in drinking water for 7 days twice daily and 7 days of tap water ad libitum between DSS treatment. Treatment with SQE was found to attenuate the severity of DSS-induced colitis, as assessed by disease activity index scores, shrinkage of colon length, and histopathologic changes. SQE reduced DSS-induced proliferation in distal colon tissues. It also significantly suppressed levels of tumor necrosis factor-α in serum and colon tissues, nitric oxide synthase, cyclooxygenase, and levels of phosphorylated c-Jun N-terminal kinases, p38, extracellular-signal-regulated kinases 1/2, and IκBα in colon tissues. To our knowledge, this is the first study to demonstrate that SQE supplementation can exert an anti-inflammatory effect on experimental chronic colitis.

Toxoplasmosis complications and novel therapeutic synergism combination of diclazuril plus atovaquone

Toxoplasmosis is a major cause of foodborne disease, congenital complication, and morbidity. There is an urgent need for safe and effective therapies to encounter congenital and persisting toxoplasmosis. The hypothesis was: combination diclazuril plus atovaquone to exert a novel therapeutic synergy to prevent toxoplasmosis syndromes.

Methods: Pregnant dams were treated with diclazuril and atovaquone monotherapy or combination therapy and infected i.p with Toxoplasma tachyzoites.

Results: Infected dams developed severe toxoplasmosis associated syndrome with increases in the abdominal adiposity surrounding uteri, gansterointestinal and other internal organs and excessive weight gain. Numerous organisms along with infiltration of inflammatory cells were detected scattered into adipose tissues. Combination therapy (p < 0.01) and to a lesser extent diclazuril (p < 0.05) protected dams from inflammatory fat and excess weight gains. This was consistent with pancreatitis development in infected dams (versus normal p < 0.05) with infiltration of inflammatory cells, degeneration and necrosis of pancreatic cells followed by the degeneration and loss of islets. Combination and monotherapy protected dams from these inflammatory and pathological aspects of pancreatitis. Infected dams exhibited severe colitis, and colonic tissues significantly shortened in length. Brush border epithelial cells were replaced with infiltration of lymphocytes, granulocytes, and microabscess formations into cryptic microstructures. Combination therapy synergistically preserved colonic structure and normalized pathological damages (p < 0.001) and to a lesser degree diclazuril monotherapy protected dams from colitis (p < 0.05) and gastrointestinal toxoplasmosis. Other complications included severe splenitis (p < 0.001) and hepatitis (p < 0.001) which were normalized with combination therapy.

Conclusion: Combination diclazuril plus atovaquone was safe and with a novel therapeutic synergism protected dams and fetuses from toxoplasmosis.

Maternal and congenital toxoplasmosis, currently available and novel therapies in horizon

Over one billion people worldwide are predicted to harbor Toxoplasma infection frequently with unknown lifelong health consequences. Toxoplasmosis is an important cause of foodborne, inflammatory illnesses, as well as congenital abnormalities. Ubiquitous Toxoplasma has a unique tropism for central nervous system with a mind-bugging effect and is transmitted sexually through semen. Currently available therapies are ineffective for persistent chronic disease and congenital toxoplasmosis or have severe side effects which may result in life-threatening complications. There is an urgent need for safe and effective therapies to eliminate or treat this cosmopolitan infectious and inflammatory disease. This investigation discusses pathogenesis of maternal and congenital toxoplasmosis, the currently available therapies in practice, and the experimental therapeutic modalities for promising future trials.

Tea polyphenols induced apoptosis of breast cancer cells by suppressing the expression of Survivin

To study the mechanism of tea polyphenols (TP)-induced apoptosis of breast cancer cells. Proliferation of MCF-7 and SK-BR-3 cells was evaluated by MTT assays. Cellular ultrastructure was examined by electron microscopy. Apoptosis was detected by TUNEL. PCNA、 Cyclin D1、 Cyclin E and Survivin expression was measured by Western blot. Cell proliferation was significantly inhibited by TP. Spindle and round cells were loosely distributed with increased particles after TP treatment. Increased cell size, frequent nuclear atypia and a collapse of apoptosis were observed. The nucleus was pushed towards one side, while the cytoplasm was rich in free ribosome. The membrane of mitochondria was thickening, and the cell apoptotic body was observed. TP treated cells experienced significantly enhanced apoptosis compared with 5-Fu treated or control groups. The expression of survivin was downregulated by TP. To conclude, TP can inhibit cell growth and induce apoptosis through downregulating the expression of survivin in breast cancer.

EGCG attenuates autoimmune arthritis by inhibition of STAT3 and HIF-1α with Th17/Treg control

Epigallocatechin-3-gallate (EGCG) is a green tea polyphenol exerting potent anti-oxidant and anti-inflammatory effects by inhibiting signaling and gene expression. The objective of the study was to evaluate the effect of EGCG on interleukin (IL)-1 receptor antagonist knockout (IL-1RaKO) autoimmune arthritis models. IL-1RaKO arthritis models were injected intraperitoneally with EGCG three times per week after the first immunization. EGCG decreased the arthritis index and showed protective effects against joint destruction in the IL-1RaKO arthritis models. The expression of pro-inflammatory cytokines, oxidative stress proteins, and p-STAT3 (Y705) and p-STAT3 (S727), mTOR and HIF-1α were significantly lower in mice treated with EGCG. EGCG reduced osteoclast markers in vivo and in vitro along with anti-osteoclastic activity was observed in EGCG-treated IL-1RaKO mice. The proportion of Foxp3(+) Treg cells increased in the spleens of mice treated with EGCG, whereas the proportion of Th17 cells reduced. In vitro, p-STAT3 (Y705) and p-STAT3 (S727), HIF1α and glycolytic pathway molecules were decreased by EGCG. EGCG suppressed the activation of mTOR and subsequently HIF-1α, which is considered as a metabolic check point of Th17/Treg differentiation supporting the therapeutic potential of EGCG in autoimmune arthritis.

Diclazuril Protects against Maternal Gastrointestinal Syndrome and Congenital Toxoplasmosis

Background

Toxoplasmosis is a common cause of foodborne, gastrointestinal and congenital syndrome with particularly severe or unknown health consequences. There is no safe and effective preventive or therapeutic modality against congenital toxoplasmosis or to eliminate the persistent chronic infection.

Hypothesis

Diclazuril to be safe in pregnancy and effective against gastrointestinal toxoplasmosis.

Methods

CD1 programmed pregnant mice were divided into groups and administered a diet containing diclazuril, or sham control. Treatments were initiated on Day 5 of pregnancy and continued until Day 16 when dams were euthanatized. On Day 8 of pregnancy dams were infected intraperitoneally with escalating doses of tachyzoites (0, 100, 300, 600) from Type II strain. Dams were monitored daily for distress, pain, and abortion and samples collected at the end of the experiments.

Results

Infected dams developed moderate to severe Toxoplasma related complications in tachyzoites dose dependent manner. Animals became anemic and showed hydrothorax, and ascities. Diclazuril effectively protected dams from ascities and anemia (p < 0.05). Infected dams showed splenomegaly, with massive infiltration of epithelioid cells compared with the protective effect of diclazuril in treated animals. Infected dams exhibited severe hepatitis (score 0 to 4 scale = 3.5 ± 0.01) with influx of inflammatory and plasma cells, dysplastic hepatocytes, multinucleated giant cell transformation and hepatic cells necrosis. Diclazuril treatment significantly protected dams from hepatitis, also in tachyzoites dose (100, 300, 600) dependent manner (respectively infected-treated versus infected controls, p < 0.001, p < 0.01 and p < 0.05). Colonic tissues were significantly shortened in length, with infiltration of lymphocytes, and macrophages and microabscess formations in the cryptic structures, with significant improvement in diclazuril treated animals. Additionally, the number of fetuses, fetal length and fetal weight were preserved in diclazuril treated dams.

Conclusions

This is the first report describing of diclazuril safety in pregnancy as well as efficacy against mild to moderate hepato-gastrointestinal syndrome in dams and fetal toxoplasmosis (Special issue, “Treatment of Liver Diseases”).

Novel Synergistic Protective Efficacy of Atovaquone and Diclazuril on Fetal-Maternal Toxoplasmosis

Over 1 billion people globally are estimated to be infected with Toxoplasma gondii with severe or unknown consequences and no safe and effective therapies are available against congenital or persistent chronic infection. We propose that atovaquone and diclazuril synergistically protect against fetal-maternal toxoplasmosis.

METHODS

Programmed pregnant mice were treated with atovaquone and diclazuril monotherapy, or combined (atovaquone + diclazuril) therapy and infected with tachyzoites (0, 300, 600) and the course of infection was studied.

RESULTS

Infected dams with low dose (300) developed moderate toxoplasmosis complications and treatments were similarly effective with minor differences between monotherapies. In contrast, major differences were observed amongst varied treatments during high-dose (600) infection and severe related- toxoplasmosis complications as follows. Dams developed hydrothorax, ascities and excess weight gain. Combined therapy (P < 0.01) and to a lesser extent diclazuril monotherapy (P < 0.05) protected dams from excess weight, hydrothorax, and ascities. Infected dams exhibited splenomegaly, hepatomegaly and severe hepatitis. Combined therapy synergistically normalized pathology (P < 0.001) and to a lesser degree monotherapy (diclazuril P < 0.01, and atovaquone P < 0.05) protected dams from hepatitis and splemomegaly. Additionally, behavioral response to pain stimuli and fetal weight and fetal numbers were significantly preserved in treated dams.

CONCLUSIONS

This is the first report describing combined atovaquone and diclazuril therapy (a) to be safe in pregnancy, (b) to exert novel synergistic effects, and (c) to protect dams and their nested fetuses against adverse effects of severe toxoplasmosis.

Panax notoginseng attenuates experimental colitis in the azoxymethane/dextran sulfate sodium mouse model

Patients suffering from inflammatory bowel disease are at a high risk of developing colorectal cancer. To assess the anticancer potential of botanicals, in this study, we evaluated the effects of Panax notoginseng on azoxymethane/dextran sulfate sodium (DSS)-induced colitis. One week after A/J mice received azoxymethane, the animals received DSS for 8 days or were supplemented with P. notoginseng extract, at 30 or 90 mg/kg. DSS-induced colitis was scored with the disease activity index. The severity of the inflammatory lesions was evaluated by a colon tissue histological assessment. The expression of inducible nitric oxide synthase and cyclooxygenase-2 (COX-2) were also explored. We observed that the effects of P. notoginseng on the reduction of colon inflammation, expressed in disease activity index score, were in a dose-related manner (p < 0.01). P. notoginseng inhibited the reduction of the colon length and the loss of bodyweight in dose-related manner (all p < 0.05). The histological assessment of the colitis and inflammatory-related immunohistochemical data also supported the pharmacological observations. Our data suggest that P. notoginseng is a promising candidate in preventing and treating colitis and inflammation-associated colon carcinogenesis.