Overview of cytokines and nitric oxide involvement in immuno-pathogenesis of inflammatory bowel diseases

In vitro immunomodulatory effect of Bifidobacterium bifidum and Lactobacillus reuteri cell free extracts

Recent studies have shown that alterations of the immune response in the gastrointestinal mucosa are key components of the mechanism of the probiotic action of beneficial bacteria. Most of the beneficial effects of probiotics are due to the action of their structural components and metabolites. Macrophages are first-line defense cells of the immune system, which not only participate in the detection, phagocytosis and destruction of harmful microorganisms, but also determine the nature of the subsequent immune response by presenting antigens to T-cells and initiating inflammation by releasing cytokines. We researched the effect of two types of cell-free extracts (CFEs) containing probiotic derivatives (structural components and metabolites of bacteria) Bifidobacterium bifidum 1 (BbCFE) and Lactobacillus reuteri DSM 17938 (LrCFE) on the activity of mouse peritoneal macrophages and on the ability of peripheral human blood mononuclear cells to produce cytokines. CFEs were obtained by culturing probiotics in their own disintegrates and then removing cells and cell debris by centrifugation and filtration. Peritoneal macrophages were isolated from mice. Some of them were infected in vitro by Salmonella thyphimurium. Uninfected and infected macrophages were incubated in culture medium containing (30% vol) or not containing CFEs at 37 °С in a microaerobic atmosphere (5% СО2) for 18 hours. After incubation, peritoneal macrophages were lysed. The obtained suspensions were centrifuged and supernatants were carefully collected. Macrophages activity was assessed by the nitrites level, superoxide dismutase (SOD), lactate dehydrogenase (LDH) activity and antiinflammatory cytokines levels in supernatants using spectrophotometric method. Peripheral mononuclear cells were isolated from the blood of healthy volunteers. The ability of peripheral mononuclear blood cells to produce antiinflammatory cytokines was evaluated after cell stimulation with lipopolysaccharide (LPS) and incubation with or without CFEs. Cytokine levels in supernatants were determined using enzyme-linked immunosorbent assay (ELISA). After infection with S. thyphimurium in macrophages, nitrite levels increased 5.5-fold, SOD activity 4.8-fold, and LDH 2-fold. Both studied CFEs exerted a similar effect on the macrophages’ activity. Addition of BbCFE to the incubation medium of infected macrophages resulted in a 4-fold decrease in nitrite levels, and the addition of LrCFE was accompanied by a decrease in nitrite levels to levels in intact cells. Under the influence of both CFEs, the activity of SOD and LDH was significantly reduced and did not differ significantly from the activity of these enzymes in intact cells. BbCFE and LrCFE did not have a significant effect on nitrite levels, SOD and LDH activity in intact macrophages. Under the influence of BbCFE, there was a 2-fold decrease in the production of TNF, a 2-fold increase in IL10 production, and a 30% increase in IL6 production by mononuclear cells. LrCFE caused a decrease in TNF production by 26.7% and IL6 by 36%, and IL10 by 1.9 times. Thus, the studied CFEs normalized the nitrite levels in peritoneal macrophages infected with S. thyphymurium and infection-induced activation of SOD and LDH enzymes. This demonstrates their ability to modulate oxidative processes in macrophages. In addition, under the influence of the investigated CFEs, there was a decrease in the production of pro-inflammatory cytokines (TNFα and IL-6) and increased production of anti-inflammatory cytokine (IL-10) by human peripheral mononuclear cells. The results of the study indicate the ability of CFEs by influencing the functions of innate immunity cells to restrict the inflammatory response and oxidative stress. Based on this, CFEs can be considered as promising agents for the treatment of inflammatory diseases.

Interleukin-32 in Infection, Inflammation and Cancer Biology

Cytokines are small pleiotropic polypeptids secreted dominantly by the cells of the immune system. These polypeptids are main mediators of innate and acquired immunity, responsible for clonal expansion and differentiation of immune cells, initiation of immune response and enhancing of effector functions of leukocytes. Cytokine-related effects are most studied in the fields of inflammation, immunology, and cancer biology. In this review we discuss one of the most intriguing, recently discovered proinflammatory cytokine, interleukin 32.

Non-thermal atmospheric pressure plasma induces epigenetic modifications that activate the expression of various cytokines and growth factors in human mesoderm-derived stem cells

Non-thermal atmospheric pressure plasma (NTAPP) has been reported to induce wound healing, activation of immune cells, and proliferation of mesoderm-derived adult stem cells in human. However, the mechanism by which NTAPP activates these physiological effects is poorly understood. Here, we examined whole genome expression profiles of adipose tissue-derived stem cells (ASCs), the proliferation of which is induced by NTAPP. NTAPP upregulated the expression of genes for cytokine and growth factor, but downregulated genes in apoptotic pathways. When ASCs were treated with NTAPP in the presence of a nitric oxide (NO) scavenger, the expression of various cytokines and growth factors decreased, suggesting that NO is primarily responsible for the enhanced cytokine and growth factor expression induced by NTAPP. Increased histone deacetyl transferase 1 (HDAC1) and decreased acetylated histone 3 were detected in NTAPP-treated ASCs. Similarly, ASCs pre-treated with HDAC, DNA methylation, or histone methylation inhibitors had reduced expression of cytokines and growth factors after NTAPP treatment. Taken together, these results strongly suggest that NTAPP induces epigenetic modifications that activate the expression of cytokines and growth factors, explaining how NTAPP acts as an efficient tool in regenerative medicine to stimulate stem cell proliferation, to activate immune cells, and to recover wounds.

Fucose Ameliorates Tryptophan Metabolism and Behavioral Abnormalities in a Mouse Model of Chronic Colitis

Growing evidence suggests that intestinal mucosa homeostasis impacts immunity, metabolism, the Central Nervous System (CNS), and behavior. Here, we investigated the effect of the monosaccharide fucose on inflammation, metabolism, intestinal microbiota, and social behavior in the Dextran Sulfate Sodium (DSS)-induced chronic colitis mouse model. Our data show that chronic colitis is accompanied by the decrease of the serum tryptophan level and the depletion of the intestinal microbiota, specifically tryptophan-producing E. coli and Bifidobacterium. These changes are associated with defects in the male mouse social behavior such as a lack of preference towards female bedding in an odor preference test. The addition of fucose to the test animals' diet altered the bacterial community, increased the abundance of tryptophan-producing E. coli, normalized blood tryptophan levels, and ameliorated social behavior deficits. At the same time, we observed no ameliorating effect of fucose on colon morphology and colitis. Our results suggest a possible mechanism by which intestinal inflammation affects social behavior in male mice. We propose fucose as a promising prebiotic, since it creates a favorable environment for the beneficial bacteria that promote normalization of serum tryptophan level and amelioration of the behavioral abnormalities in the odor preference test.

Anti-oxidant and anti-inflammatory effect of polar extracts obtained from waste product of wine making

A lot of diseases are characterized by an increased inflammatory response with an exacerbated production of free radicals. The anti-inflammatory effect of different compounds with antioxidant capacity, as polyphenols present in grape is well known. Therefore, the objective is to evaluate the anti-oxidant and anti-inflammatory activity of waste product of wine production.Six different non-toxic-marc-polar extracts from Malbec and Syrah grape varieties were obtained, their total phenol and flavonoid content were evaluated, and their antioxidant and anti-inflammatory activity were determined.High content of total phenols and flavonoids were found mainly in extracts obtained from Syrah (80.51 ± 16.63 g equivalent to gallic acid/100 g and 25.47 ± 3.33 g equivalent to quercetin/100 g). In addition, they had a high antioxidant effect (above 88.5% of ABTS inhibition by Syrah extracts). Finally, all extracts decreased the nitric oxide (NO) production, but this was more accented when extract from Syrah obtained by infusion was used, which decreased NO levels to baseline (4.46 µM).Taking together, our results show the potential pharmaceutical use of waste product of wine making to prevent or to treat diseases which inflammatory response is exacerbated.

Effect of Loureirin B on Crohn's disease rat model induced by TNBS via IL-6/STAT3/NF-κB signaling pathway

Background

Crohn’s disease (CD) is a chronic relapsing form of inflammatory bowel disease, seriously threatening human beings health. However, the pathogenesis of CD is still unclear and there is no specific effective drug for treatment of CD. Resina Donis (RD) obtained from Dracaena cochinchinensis (Lour.) S. C. Chen (Liliaceae), has been used for the treatment of CD clinically. Loureirin B (LB) is one of the most important chemical compositions and physiologically active ingredients of resina draconis. It has the molecular structure propan-1-one, 1-(4-hydroxyphenyl)-3-(2,4,6-trimethoxyphenyl)-1-(4-hydroxyphenyl)-3-(2,4,6-trimethoxyphenyl) propan-1-one. The aim of this study was to investigate the effect of LB on CD and explore the underlying mechanisms.

Methods and results

In this study, the result demonstrated that LB prolonged the survival time of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced rats and alleviated colonic damage in a dose dependent manner. Besides, LB remarkably ameliorated TNBS-induced inflammatory response via regulation of cytokines in the colonic tissues. Moreover, LB could reverse the established fibrosis and impede the accumulation infiltration, and improve the apoptosis induced by TNBS in a dose dependent manner. Further, LB dramatically suppressed TNBS-induced the activation of IL-6/STAT3/NF-κB signaling pathway.

Conclusions

These findings suggested that LB could be beneficial regarding ameliorating TNBS-induced CD, which may represent a novel approach to treat CD and provide an alternative choice for disorders associated with CD.

Microalgae aqueous extracts exert intestinal protective effects in Caco-2 cells and dextran sodium sulphate-induced mouse colitis

Aqueous extracts from Chlorella pyrenoidosa, Spirulina platensis and Synechococcus sp. PCC 7002 showed gut protective potential in vitro and in vivo.

Effect of dehydroepiandrosterone on the immune response and gut microbiota in dextran sulfate sodium-induced colitis mice

Dehydroepiandrosterone (DHEA) possess anti-inflammatory, anti-oxidant and immune-regulating function in animals and humans, but there is not enough information about the mechanisms underlying its beneficial effects. The present study investigated the effect and mechanism of DHEA in dextran sulfate sodium (DSS)-induced colitis mice. The findings showed that DHEA relieved the decreasing of body weight, the increasing of disease activity index, the enhancing of spleen weight, the shortening of colon length and the rising of myeloperoxidase activity; meanwhile, histopathological analysis showed that DHEA maintained a relatively intact structure of colon in DSS-induced colitis mice. DHEA decreased the malondialdehyde content, superoxide dismutase activity and inducible nitric oxide synthase protein level; meanwhile, DHEA also inhibited the secretion of tumor necrosis factor-α, interleukin-1β and interleukin-6 in DSS-induced colitis mice. Importantly, our results showed that DHEA blocked the activation of nuclear factor-kappa B (NF-κB) and p38 mitogen-activated protein kinase (MAPK) pathways; and it inhibited the Nod-like receptor protein 3 inflammasome activation in DSS-induced colitis mice. Furthermore, DHEA markedly promoted the intestinal barrier function by up-regulation zonula occludens-1 expression level. The 16S rDNA gene sequencing demonstrated that DHEA decreased the Pseudomonas abundance in DSS-induced colitis mice. In conclusion, our data demonstrated that DHEA reduces oxidative damage through regulating antioxidant enzyme activity; inhibits pro-inflammatory cytokines production by blocking the activation of p38 MAPK and NF-κB signal pathway; protects colon barrier integrity via increasing tight junction protein expression and modulating gut microbiota taxa; all that finally alleviates DSS-induced experimental colitis in mice.

Jinzhi protects lipopolysaccharide-treated mice against mortality by repairing intestinal mucosal barrier damage and intestinal microecology

OBJECTIVE

Intestinal mucosal barrier damage is an important mechanism for the development of sepsis and multiple organ dysfunction syndrome. At present, there are no satisfactory and effective methods for the protection of the intestinal mucosal barrier. Jinzhi, the first fecal microbiota transplantation worldwide, is often used to treat critically ill patients; however, the specific mechanism involved in this process remains unclear. The aim of this study was to investigate the therapeutic effect and mechanism of Jinzhi intervention on mice with sepsis induced through treatment with lipopolysaccharide (LPS).

METHODS

Mice were intraperitoneally injected with LPS to simulate intestinal mucosal barrier function damage in sepsis; intervention was performed through the oral administration of Jinzhi. The effect of Jinzhi on LPS-induced sepsis was analyzed by comparing the vital signs and survival rate of mice under different treatments. Pathological staining and enzyme-linked immunosorbent assay were used to identify the effects of LPS or treatment with Jinzhi on the intestinal mucosal barrier in mice. The effect of LPS or treatment with Jinzhi on the intestinal flora was analyzed via 16S rRNA gene sequencing of ileal contents.

RESULTS

Immunohistochemistry and enzyme-linked immunosorbent assay showed that treatment with LPS increased levels of inflammatory factors (interleukin-1α, interleukin-6, tumor necrosis factor-α), caspase-3, and caspase-8 in the serum and ileum, and destroyed the tight junction between epithelial cells. Intervention with Jinzhi reduced levels of serum LPS and tumor necrosis factor-α, and repaired the tight junction between epithelial cells. Furthermore, 16S rRNA gene sequencing analysis showed that treatment with Jinzhi improved the diversity and physiological function of the intestinal flora.

CONCLUSIONS

These results suggest that Jinzhi may be a promising option for the treatment of sepsis caused by LPS, and emphasize that Jinzhi exerts a recovery effect on the imbalance of intestinal flora.

Curcumin ameliorates dextran sulfate sodium-induced colitis in mice via regulation of autophagy and intestinal immunity

BACKGROUND/AIMS

Inflammatory bowel disease (IBD) is regarded as a kind of chronic and unspecific intestinal inflammatory disorder. Its exact pathogenesis has not been elucidated. Curcumin, as an herbal drug, has been used in the treatment of IBD due to its immunoregulation. Autophagy has been reported to play an important role in the mechanism of IBD. In the present study, we focused on the autophagic regulation role of curcumin in the murine model of dextran sulfate sodium (DSS)-induced colitis.

MATERIALS AND METHODS

We investigated the effects of curcumin on the progress of DSS-induced acute colitis in mice by evaluating the disease activity index (DAI) and histopathological score. Meanwhile, the mRNA and protein expression of autophagy-related key genes from colon tissues comprising autophagy-related 5 (ATG5), LC3-phosphatidylethanolamine conjugate (LC-3II), beclin-1, and B cell lymphoma 2 (bcl-2) was examined by quantitative reverse transcription polymerase chain reaction and Western blot. Furthermore, the mRNA and protein expression of cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL) 6, IL-10, and IL-17A, was examined. Autophagosome was also examined under transmission electron microscopy.

RESULTS

Both DAI and histopathological score increased in mice with DSS-induced colitis and obviously decreased after curcumin intervention. The expression levels of TNF-α, IL-6, IL-17, ATG5, LC-3II, and beclin-1 were significantly higher in mice with colitis than in normal ones, whereas those of IL-10 and bcl-2 decreased accordingly. However, curcumin intervention adjusted the expression level of those factors toward normal level. The number of autophagosome in the colon epithelia increased after DSS stimulation and decreased after curcumin administration.

CONCLUSION

Curcumin could prevent the development of DSS-induced colitis through the inhibition of excessive autophagy and regulation of following cytokine networks.

Induction of Nitric-Oxide Metabolism in Enterocytes Alleviates Colitis and Inflammation-Associated Colon Cancer

Nitric oxide (NO) plays an established role in numerous physiological and pathological processes, but the specific cellular sources of NO in disease pathogenesis remain unclear, preventing the implementation of NO-related therapy. Argininosuccinate lyase (ASL) is the only enzyme able to produce arginine, the substrate for NO generation by nitric oxide synthase (NOS) isoforms. Here, we generated cell-specific conditional ASL knockout mice in combination with genetic and chemical colitis models. We demonstrate that NO derived from enterocytes alleviates colitis by decreasing macrophage infiltration and tissue damage, whereas immune cell-derived NO is associated with macrophage activation, resulting in increased severity of inflammation. We find that induction of endogenous NO production by enterocytes with supplements that upregulate ASL expression and complement its substrates results in improved epithelial integrity and alleviation of colitis and of inflammation-associated colon cancer.

NF-κB2 signalling in enteroids modulates enterocyte responses to secreted factors from bone marrow-derived dendritic cells

Alternative pathway NF-κB signalling regulates susceptibility towards developing inflammatory bowel disease (IBD), colitis-associated cancer and sepsis-associated intestinal epithelial cell apoptosis and shedding. However, the cell populations responsible for the perturbed alternative pathway NF-κB signalling in intestinal mucosal pathology remain unclear. In order to investigate the contribution of the epithelial compartment, we have tested whether NF-κB2 regulated transcription in intestinal epithelial cells controls the intestinal epithelial response to cytokines that are known to disrupt intestinal barrier permeability. Enteroids were generated from the proximal, middle and distal regions of small intestine (SI) from C57BL/6J wild-type mice and displayed region-specific morphology that was maintained during sub-culture. Enteroids treated with 100 ng/mL TNF were compared with corresponding regions of SI from C57BL/6J mice treated systemically with 0.33 mg/kg TNF for 1.5 h. TNF-induced apoptosis in all regions of the intestine in vitro and in vivo but resulted in Paneth cell degranulation only in proximal tissue-derived SI and enteroids. TNF also resulted in increased enteroid sphericity (quantified as circularity from two-dimensional bright field images). This response was dose and time-dependent and correlated with active caspase-3 immunopositivity. Proximal tissue-derived enteroids generated from Nfκb2^−/− mice showed a significantly blunted circularity response following the addition of TNF, IFNγ, lipopolysaccharide (LPS) activated C57BL/6J-derived bone marrow-derived dendritic cells (BMDC) and secreted factors from LPS-activated BMDCs. However, Nfκb1^−/− mouse-derived enteroids showed no significant changes in response to these stimuli. In conclusion, the selection of SI region is important when designing enteroid studies as region-specific identity and response to stimuli such as TNF are maintained in culture. Intestinal epithelial cells are at least partially responsible for regulating their own fate by modulating NF-κB2 signalling in response to stimuli known to be involved in multiple intestinal and systemic diseases. Future studies are warranted to investigate the therapeutic potential of intestinal epithelial NF-κB2 inhibition.

Perilla frutescens Britton var. frutescens leaves attenuate dextran sulfate sodium-induced acute colitis in mice and lipopolysaccharide-stimulated angiogenic processes in human umbilical vein endothelial cells

The aim of the current study was to investigate whether the leaves of Perilla frutescens Britton var. frutescens (PL), a frequently consumed vegetable in Korea, attenuate dextran sulfate sodium (DSS)-induced acute colitis in mice and lipopolysaccharide (LPS)-stimulated angiogenic processes in human umbilical vein endothelial cells (HUVEC). In DSS-treated mice, dietary supplementation with PL mitigated DAI and colon shortening. The dietary PL also reduced colonic levels of inflammatory and angiogenic mediators, such as interleukin-1β, interleukin-6, monocyte chemoattractant protein-1, macrophage inflammatory protein-2, leukotriene B₄, inducible nitric oxide synthase, cyclooxygenase-2, basic fibroblast growth factor, and intercellular adhesion molecule-1 (ICAM-1). Treatment of HUVEC with ethanol extract of PL attenuated LPS-stimulated increases in ICAM-1 levels, monocyte adhesion, invasion, and tube formation. This study suggests that dietary PL effectively inhibited DSS-induced acute colitis in mice, and its anti-angiogenic activities may partially contribute to the inhibition.

Huang-Lian-Jie-Du Decoction Ameliorates Acute Ulcerative Colitis in Mice via Regulating NF-κB and Nrf2 Signaling Pathways and Enhancing Intestinal Barrier Function

Evidence shows that intestinal inflammation, oxidative stress, and injury of mucosal barrier are closely related to the pathogenesis of ulcerative colitis (UC). Huang-lian-Jie-du Decoction (HLJDD) is a well-known prescription of traditional Chinese medicine with anti-inflammatory and antioxidative activities, which may be used to treat UC. However, its therapeutic effect and mechanism are still unclear. In this study, the UC model of BABL/c mice were established by DSS [3.5% (w/v)], and HLJDD was given orally for treatment at the same time. During the experiment, the clinical symptoms of mice were scored by disease activity index (DAI). Besides, the effects of HLJDD on immune function, oxidative stress, colon NF-κB and Nrf2 signaling pathway, and intestinal mucosal barrier function in UC mice were also investigated. The results showed that HLJDD could alleviate body weight loss and DAI score of UC mice, inhibit colonic shortening and relieve colonic pathological damage, and reduce plasma and colon MPO levels. In addition, HLJDD treatment significantly up-regulated plasma IL-10, down-regulated TNF-α and IL-1β levels, and inhibited the expression of NF-κB p65, p-IκKα/β, and p-IκBα proteins in the colon. Moreover, NO and MDA levels in colon tissues were significantly reduced after HLJDD treatment, while GSH, SOD levels and Nrf2, Keap1 protein expression levels were remarkably elevated. Additionally, HLJDD also protected intestinal mucosa by increasing the secretion of mucin and the expression of ZO-1 and occludin in colonic mucosa. These results indicate that HLJDD could effectively alleviate DSS-induced mice UC by suppressing NF-κB signaling pathway, activating Nrf2 signaling pathway, and enhancing intestinal barrier function.

Soluble Fraction from Lysates of Selected Probiotic Strains Differently Influences Re-Epithelialization of HaCaT Scratched Monolayer through a Mechanism Involving Nitric Oxide Synthase 2

A growing body of evidence supports the use of probiotics in the treatment of several skin conditions, including wounds. Even if in vitro and in vivo studies have highlighted the pro-healing effects of some probiotic bacteria, the underlying mechanisms are still not fully defined. The current investigation aimed to determine the re-epithelialization potential of the soluble fraction from lysate of seven different probiotic strains belonging to different genera (i.e., Streptococcus, Lactobacillus, and Bifidobacterium) on in vitro physically wounded HaCaT monolayer model. The results suggested that the soluble fraction of S. thermophilus, L. plantarum, and L. acidophilus promoted the re-epithelialization of scratched HaCaT monolayers, whereas those from B. longum, B. infantis, and B. breve significantly inhibited the process. On the other hand, L. bulgaricus showed no significant effect on in vitro wound repair. The mechanisms underlying the pro- or anti-healing properties of selected bacterial strains strictly and positively correlated with their ability to modulate nitric oxide synthase 2 (NOS2) expression and activity. Accordingly, the pre-treatment with aminoguanidine (AG), a specific inhibitor of NOS2 activity, abrogated the pro-healing effects of S. thermophilus, L. plantarum, and L. acidophilus.

Supplementation with nitrate only modestly affects lipid and glucose metabolism in genetic and dietary-induced murine models of obesity

To gain a better understanding of how nitrate may affect carbohydrate and lipid metabolism, female wild-type mice were fed a high-fat, high-fructose diet supplemented with either 0, 400, or 800 mg nitrate/kg diet for 28 days. Additionally, obese female db/db mice were fed a 5% fat diet supplemented with the same levels and source of nitrate. Nitrate decreased the sodium-dependent uptake of glucose by ileal mucosa in wild-type mice. Moreover, nitrate significantly decreased triglyceride content and mRNA expression levels of Pparγ in liver and Glut4 in skeletal muscle. Oral glucose tolerance as well as plasma cholesterol, triglyceride, insulin, leptin, glucose and the activity of ALT did not significantly differ between experimental groups but was higher in db/db mice than in wild-type mice. Nitrate changed liver fatty acid composition and mRNA levels of Fads only slightly. Further hepatic genes encoding proteins involved in lipid and carbohydrate metabolism were not significantly different between the three groups. Biomarkers of inflammation and autophagy in the liver were not affected by the different dietary treatments. Overall, the present data suggest that short-term dietary supplementation with inorganic nitrate has only modest effects on carbohydrate and lipid metabolism in genetic and dietary-induced mouse models of obesity.

Effects of Anti-Cytokine Antibodies on Gut Barrier Function

Anti-cytokine antibodies are used in treating chronic inflammatory diseases and autoimmune diseases such as inflammatory bowel disease and rheumatic diseases. Patients with these diseases often have a compromised gut barrier function, suggesting that anti-cytokine antibodies may contribute to the re-establishment of gut barrier integrity, in addition to their immunomodulatory effects. This paper reviews the effects of anti-cytokine antibodies on gut barrier function and their mechanisms.

Oxygen radical disease in the newborn, revisited: Oxidative stress and disease in the newborn period

Thirty years ago, there was an emerging appreciation for the significance of oxidative stress in newborn disease. This prompted a renewed interest in the impact of oxygen therapy for the newborn in the delivery room and beyond, especially in premature infants. Today, the complexity of oxidative stress both in normal regulation and pathology is better understood, especially as it relates to neonatal mitochondrial oxidative stress responses to hyperoxia. Mitochondria are recipients of oxidative damage and have a propensity for oxidative self-injury that has been implicated in the pathogenesis of neonatal lung diseases. Similarly, both intrauterine growth restriction (IUGR) and macrosomia are associated with mitochondrial dysfunction and oxidative stress. Additionally, reoxygenation with 100% O₂ in a hypoxic-ischemic newborn lamb model increased the production of pro-inflammatory cytokines in the brain. Moreover, the interplay between inflammation and oxidative stress in the newborn is better understood because of animal studies. Transcriptomic analyses have found a number of genes to be differentially expressed in murine models of bronchopulmonary dysplasia (BPD). Epigenetic changes have also been detected both in animal models of BPD and premature infants exposed to oxygen. Antioxidant therapy to prevent newborn disease has not been very successful; however, new therapeutic principles, like melatonin, are under investigation.

Novel and Stable Dual-Color IL-6 and IL-10 Reporters Derived from RAW 264.7 for Anti-Inflammation Screening of Natural Products

Our previous study suggested that the interleukin (IL)-6 and IL-10 could serve as good biomarkers for chronic inflammatory disease. We previously established an IL-6 and IL-10 reporters assay that could examine reporter activity along with the reference gene in LPS-induced RAW 264.7 cells. In this study, we described new and stable RAW 264.7 derived dual-color IL-6/gapdh and IL-10/gapdh reporters. This assay allowed us to easily determine relative IL-6 and IL-10 levels with 96-well plate within one step. We evaluated the relative IL-6 and IL-10 levels in the LPS-induced stable cells testing 52 natural products by real-time bioluminescence monitoring and time-point determination using a microplate luminometer. The relative IL-6 and IL-6/IL-10 values decreased by the crude ethanol extracts from nutmeg and by 1′S-1′-acetoxychavicol from greater galangal using real-time bioluminescence monitoring. At the same time, the relative IL-10 was induced. The relative IL-6 and IL-6/IL-10 decreased by crude ethanol extracts from nutmeg and 1′S-1′-acetoxychavicol acetate at 6 h. Only crude ethanol extract from nutmeg induced IL-10 at 6 h. We suggested that the use of these stable cells by real-time monitoring could serve as a screening assay for anti-inflammatory activity and may be used to discover new drugs against chronic inflammatory disease.

A Mixture of Polyunsaturated Fatty Acids ω-3 and ω-6 Reduces Melanoma Growth by Inhibiting Inflammatory Mediators in the Murine Tumor Microenvironment

Background: Although it has been previously demonstrated that acute inflammation can promote the tumor growth of a sub-tumorigenic dose of melanoma cells through of 5-lipoxygenase inflammatory pathway and its product leukotriene B_4, and also that the peritumoral treatment with eicosapentaenoic acid and its product, leukotriene B₅, reduces the tumor development, the effect of the treatment by gavage with omega-3 and omega-6 in the tumor microenvironment favorable to melanoma growth associated with acute inflammation has never been studied. Methods: C57BL/6 mice were coinjected with 1 × 10⁶ apoptotic cells plus 1 × 10³ viable melanoma cells into the subcutaneous tissue and treated by gavage with omega-3-rich fish oil or omega-6-rich soybean oil or a mixture of these oils (1:1 ratio) during five consecutive days. Results: The treatment by gavage with a mixture of fish and soybean oils (1:1 ratio) both reduced the melanoma growth and the levels of leukotriene B₄ (LTB₄), prostaglandin E₂ (PGE₂), PGE₂/prostaglandin E₃ (PGE₃) ratio, and CXC ligand 1 (CXCL1) and increased the levels of interleukin 10 (IL-10) to IL-10/CXCL1 ratio in the melanoma microenvironment. Conclusion: The oral administration of a 1:1 mixture of fish oil and soybean oil was able to alter the release of inflammatory mediators that are essential for a microenvironment favorable to the melanoma growth in mice, whereas fish oil or soybean oil alone was ineffective.

Total Alkaloids from Bamboo Shoots and Bamboo Shoot Shells of Pleioblastus amarus (Keng) Keng f. and Their Anti-Inflammatory Activities

The bamboo shoot of Pleioblastus amarus (Keng) Keng f. is a medicinal and edible plant product in China. In this study, the chemical composition of the total alkaloids from bamboo shoots and bamboo shoot shells of P. amarus (Keng) Keng f. (ABSP and ABSSP, respectively) were separated and investigated by UHPLC/QTOF-MS/MS. The results showed that a total of 32 alkaloids were extracted, with 15 common to both ABSP and ABSSP and 10 and 7 alkaloids distinct to ABSP and ABSSP, respectively. ABSP and ABSSP both decreased the lipopolysaccharide (LPS, 0.5 μg/mL)-induced nitric oxide (NO) production in RAW264.7 murine macrophages with half maximal inhibitory concentration (IC50) values of 78 and 55 μg/mL, respectively. We also found that ABSP and ABSSP (100 μg/mL) could decrease the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at both mRNA and protein levels in LPS-exposed RAW264.7 cells. Moreover, 100 μg/mL of ABSP and ABSSP also significantly inhibited LPS-induced mRNA expression of interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α). Additionally, ABSP and ABSSP (100 μg/mL) decreased the phosphorylation of extracellular regulated protein kinase (ERK) in LPS-stimulated RAW264.7 cells. Collectively, the total alkaloids from the bamboo shoots and shells of P. amarus exhibit anti-inflammatory effects in LPS-activated RAW264.7 cells through the inhibition of ERK signaling. This result can provide support for the medicinal use and further study of P. amarus.

Polyphenols and IUGR Pregnancies: Effects of Maternal Hydroxytyrosol Supplementation on Hepatic Fat Accretion and Energy and Fatty Acids Profile of Fetal Tissues

Maternal supplementation with hydroxytyrosol, a polyphenol present in olive leaves and fruits, is a highly promising strategy to improve the oxidative and metabolic status of fetuses at risk of intrauterine growth restriction, which may diminish the appearance of low-birth-weight neonates. The present study aimed to determine whether hydroxytyrosol, by preventing lipid peroxidation, may influence the fat accretion and energy homeostasis in the liver, as well as the fatty acid composition in the liver and muscle. The results indicate that hydroxytyrosol treatment significantly decreased the energy content of the fetal liver, without affecting fat accretion, and caused significant changes in the availability of fatty acids. There were significant increases in the amount of total polyunsaturated fatty acids, omega-3 and omega-6, which are highly important for adequate fetal tissue development. However, there were increases in the omega-6/omega-3 ratio and the desaturation index, which make further studies necessary to determine possible effects on the pro/anti-inflammatory status of the fetuses.

Veronica Plants-Drifting from Farm to Traditional Healing, Food Application, and Phytopharmacology

The Veronica genus, with more than 200 species, belongs to the Plantaginaceae family and is distributed over most of the Northern Hemisphere and in many parts of Southern Hemisphere. These plants are traditionally used in medicine for wound healing, in the treatment of rheumatism, and in different human diseases. This paper reviews the chemical composition of some valuable Veronica species, the possibilities Veronica extracts have in food preservation and as food ingredients, and their functional properties. Veronica species represent a valuable source of biological active secondary metabolites, including iridoid glycosides and phenolic compounds. In particular, due to presence of these phytochemicals, Veronica species exhibit a wide spectrum of biological activities, including antimicrobial and antioxidant. In fact, some studies suggest that some Veronica extracts can inhibit foodborne pathogens, such as Listeria monocytogenes, but only a few of them were performed in food systems. Moreover, anticancer, anti-inflammatory, and other bioactivities were reported in vitro and in vivo. The bioactivity of Veronica plants was demonstrated, but further studies in food systems and in humans are required.

Interleukin-13 and interleukin-33 mRNA are underexpressed in the duodenal mucosa of German Shepherd dogs with chronic enteropathy

BACKGROUND

A recent genome-wide association study in German Shepherd dogs (GSDs) with chronic enteropathy (CE) has identified polymorphisms in the Th2 cytokine genes.

HYPOTHESIS/OBJECTIVE

To determine if the expression of the Th2 cytokines, interleukin-13 (IL-13) and interleukin-33 (IL-33), is altered in the duodenal mucosa of GSDs with CE compared to non-GSDs with CE and healthy dogs.

ANIMALS

Twenty client-owned dogs diagnosed with CE (10 GSDs and 10 non-GSDs) at the Bristol Veterinary School and 8 healthy Beagle dogs from the Iowa State University Service Colony.

METHODS

Retrospective study using archived paraffin-embedded duodenal biopsy samples. A novel RNA in situ hybridization technology (RNAscope) was used to hybridize IL-13 and IL-33 mRNA probes onto at least 10 sections from duodenal biopsy samples for each dog. RNAscope signals were visualized using a microscope and semi-quantitative assessment was performed by a single operator.

RESULTS

Based on duodenal villus, subvillus, epithelial, and lamina propria average expression scores, GSDs with CE had significantly lower IL-13 and IL-33 mRNA expression compared to non-GSDs with CE (IL-13, P < .04; IL-33, P < .02) and healthy Beagle dogs (IL-13, P < .02; IL-33, P < .004).

CONCLUSIONS AND CLINICAL IMPORTANCE

Similar to human patients with ulcerative colitis, a subtype of human inflammatory bowel disease, these data indicate that Th2 cytokines may be involved in the pathogenesis of CE in GSDs.

Qing Chang Hua Shi granule ameliorate inflammation in experimental rats and cell model of ulcerative colitis through MEK/ERK signaling pathway

Ulcerative colitis (UC), a bowel disease with significant morbidity, is associated with inflammation. In this study, the effect of Qingchang Huashi granule (QCHS) on UC and its underlying mechanisms were explored using both animal and cell culture experiments. A rat UC model was induced with trinitro-benzene-sulfonic acid (TNBS), concentrations of the cytokines IL-1α, IL-6, IL-8, IL-1β, and TNF-α were significantly up-regulated and the concentrations of IL-4, IL-10, and IL-13 were significantly down-regulated compared with the control group (P < 0.05). In contrast, the QCHS and salicylazosulfapyridine (SASP) groups reversed these modulations (P < 0.05). A UC cell model in HT-29 cells was generated using TNF-α combined with lipopolysaccharide treatment. Cells treated with QCHS were used to investigate the possible mechanisms. The expression of apoptosis-related proteins, including Bax/Bcl-2, caspase-3, caspase-9, Fas/Fas-L, and Rafl in the QCHS and SASP groups, were significantly lower than that in the control group in both animal and cell experiments (P < 0.05). In addition, the in vitro results indicate changes in these indicators mediate the MEK/ERK signaling pathways via SGK1. Our results suggested that QCHS could be beneficial in preventing UC progression as an alternative drug for UC treatment.

Unconjugated bilirubin alleviates experimental ulcerative colitis by regulating intestinal barrier function and immune inflammation

BACKGROUND

Unconjugated bilirubin (UCB) is generally considered toxic but has gained recent prominence for its anti-inflammatory properties. However, the effects of it on the interaction between intestinal flora and organisms and how it influences immune responses remain unresolved.

AIM

To investigate the role of UCB in intestinal barrier function and immune inflammation in mice with dextran-sulfate-sodium-induced colitis.

METHODS

Acute colitis was induced by 3% (w/v) dextran sulfate sodium salt in drinking water for 6 d followed by untreated water for 2 d. Concurrently, mice with colitis were administered 0.2 mL UCB (400 μmol/L) by intra-gastric gavage for 7 d. Disease activity index (DAI) was monitored daily. Mice were sacrificed at the end of the experiment. The length of the colon and weight of the spleen were recorded. Serum level of D-lactate, intestinal digestive proteases activity, and changes to the gut flora were analyzed. In addition, colonic specimens were analyzed by histology and for expression of inflammatory markers and proteins.

RESULTS

Mice treated with UCB had significantly relieved severity of colitis, including lower DAI, longer colon length, and lower spleen weight (colon length: 4.92 ± 0.09 cm vs 3.9 ± 0.15 cm; spleen weight: 0.33 ± 0.04 vs 0.74 ± 0.04, P < 0.001). UCB administration inactivated digestive proteases (chymotrypsin: 18.70 ± 0.69 U/g vs 44.81 ± 8.60 U/g; trypsin: 1.52 ± 0.23 U/g vs 9.05 ± 1.77 U/g, P < 0.01), increased expression of tight junction (0.99 ± 0.05 vs 0.57 ± 0.03, P < 0.001), decreased serum level of D-lactate (31.76 ± 3.37 μmol/L vs 54.25 ± 1.45 μmol/L, P < 0.001), and lowered histopathological score (4 ± 0.57 vs 7 ± 0.57, P < 0.001) and activity of myeloperoxidase (46.79 ± 2.57 U/g vs 110.32 ± 19.19 U/g, P < 0.001). UCB also regulated the intestinal microbiota, inhibited expression of tumor necrosis factor (TNF) α and interleukin 1β (TNF-α: 52.61 ± 7.81 pg/mg vs 105.04 ± 11.92 pg/mg, interleukin 1β: 13.43 ± 1.68 vs 32.41 ± 4.62 pg/mg, P < 0.001), decreased expression of Toll-like receptor 4 (0.61 ± 0.09 vs 1.07 ± 0.03, P < 0.001) and myeloid differentiation primary response gene 88 (0.73 ± 0.08 vs 1.01 ± 0.07, P < 0.05), and increased expression of TNF-receptor-associated factor 6 (0.79 ± 0.02 vs 0.43 ± 0.09 P < 0.05) and inhibitor of kappa B α (0.93 ± 0.07 vs 0.72 ± 0.07, P < 0.05) in the colon.

CONCLUSION

UCB can protect intestinal barrier function, regulate normal intestinal homeostasis, and suppress inflammation via the Toll-like receptor 4/ nuclear factor-κB signaling pathway.

The Role of Nitric Oxide in Regulating Intestinal Redox Status and Intestinal Epithelial Cell Functionality

Important functions of intestinal epithelial cells (IECs) include enabling nutrient absorption to occur passively and acting as a defense barrier against potential xenobiotic components and pathogens. A compromise to IEC function can result in the translocation of bacteria, toxins, and allergens that lead to the onset of disease. Thus, the maintenance and optimal function of IECs are critically important to ensure health. Endogenous biosynthesis of nitric oxide (NO) regulates IEC functionality both directly, through free radical activity, and indirectly through cell signaling mechanisms that impact tight junction protein expression. In this paper, we review the current knowledge on factors that regulate inducible nitric oxide synthase (iNOS) and the subsequent roles that NO has on maintaining IECs' intestinal epithelial barrier structure, functions, and associated mechanisms of action. We also summarize important findings on the effects of bioactive dietary food components that interact with NO production and affect downstream intestinal epithelium integrity.

Effects of different processing methods on the antioxidant and immune stimulating abilities of garlic

In this study, we determined the antioxidant and immune stimulating abilities of a garlic product developed by freeze drying, heat drying, and solid-state fermentation of heat-dried garlic. Lactobacillus plantarum KCTC21004 and Leuconostoc mesenteroides KCTC13302 were used for the sample fermentation. The optimum conditions for fermentation were 50% (v/w) moisture, a fermentation time of 48 hr and a temperature of 37°C. Heat-dried garlic samples fermented with L. plantarum KCTC21004 (HD21004) and L. mesenteroides KCTC13302 (HD13302) showed the highest flavonoid contents while heat-dried garlic (HD) had the lowest flavonoid content. HD21004 contained the highest phenolic compounds, showed the highest antioxidant activity and demonstrated a strong immune stimulating effect while freeze-dried garlic showed the lowest flavonoid and polyphenolic contents. Overall, the heat-dried garlic samples (fermented and unfermented) contained about three times more S-Allylcysteine (SAC) than the freeze-dried samples (FD). The current study demonstrates that heat drying and subsequent fermentation of garlic with L. plantarum KCTC21004 can improve its therapeutic effects.

Anthriscus sylvestris root extract reduces allergic lung inflammation by regulating interferon regulatory factor 4-mediated Th2 cell activation

ETHNOPHARMACOLOGICAL RELEVANCE

Anthriscus sylvestris L. Hoffmann (AS) is a perennial plant that grows in Asia and Eastern Europe. Its dried root is used to treat conditions such as asthma, bronchitis, and cough.

AIM OF THE STUDY

The present study investigated the anti-inflammatory effects of whole AS extract (ASE) on allergic lung inflammation in vitro and in vivo as well as the underlying mechanisms.

MATERIALS AND METHODS

We used an ovalbumin (OVA)-induced asthma mouse model and in vitro primary T helper (Th)2 polarization system. Five groups of 8-week-old female C57BL/6 mice were divided into the following groups: saline control, or OVA-induced allergic asthma with vehicle, ASE (100 or 200 mg/kg), or dexamethasone (5 mg/kg) treatment for 7 days.

RESULTS

ASE attenuated mucus secretion in airway epithelial cells, inflammatory cell infiltration, eosinophilia, and Th2 cytokine levels in bronchoalveolar lavage fluid. Mice administered ASE showed reductions in the activated cluster of differentiation 4⁺ T cell population and GATA-binding protein-3 gene expression in the lung, and diminished Th2 cell differentiation and activation in vitro. Furthermore, ASE-treated mice showed decreased interleukin-6 and interferon regulatory factor (IRF)4 expression, with corresponding reductions in nitric oxide levels in the lungs of asthmatic mice and in stimulated RAW cells.

CONCLUSION

ASE exerts anti-asthmatic effects by inhibiting IRF4 expression and thereby suppressing Th2 cell activation.

Roles of Na+/Ca2+ exchanger 1 in digestive system physiology and pathophysiology

The Na⁺/Ca²⁺ exchanger (NCX) protein family is a part of the cation/Ca²⁺ exchanger superfamily and participates in the regulation of cellular Ca²⁺ homeostasis. NCX1, the most important subtype in the NCX family, is expressed widely in various organs and tissues in mammals and plays an especially important role in the physiological and pathological processes of nerves and the cardiovascular system. In the past few years, the function of NCX1 in the digestive system has received increasing attention; NCX1 not only participates in the healing process of gastric ulcer and gastric mucosal injury but also mediates the development of digestive cancer, acute pancreatitis, and intestinal absorption. This review aims to explore the roles of NCX1 in digestive system physiology and pathophysiology in order to guide clinical treatments.

Inhibitory effects of cranberry polyphenol and volatile extracts on nitric oxide production in LPS activated RAW 264.7 macrophages

Cranberry volatiles have received little attention for health-promoting properties.

The effects of crocin, mesalazine and their combination in the acetic acid-induced colitis in rats

Crocin, as a carotenoid compound of saffron, exerts a potent antioxidant property. Mesalazine is frequently used in the treatment of ulcerative colitis. This study investigated the effects of separated and combination treatments with crocin and mesalazine in a rat model of ulcerative colitis. Ulcerative colitis was induced by intra-colonic administration of acetic acid (4.00%, 1.00 mL) at 8 cm proximal of the anus. Normal saline, acetic acid, crocin (5.00, 10.00 and 20.00 mg kg^-1), mesalazine (100 and 300 mg kg^-1) and crocin (5.00 mg kg^-1) plus mesalazine (100 mg kg^-1) were administered after induction of colitis for eight days. Body weight, organosomatic index (OSI), macroscopic and microscopic evaluations of colon and measurement of malondialdehyde (MDA), superoxide dismutase (SOD), tumor necrosis factor-alpha (TNF-α) contents of colon tissue were determined on day eight after induction of colitis. Crocin (10.00 and 20.00 mg kg^-1), mesalazine (300 mg kg^-1) and crocin (5.00 mg kg^-1) plus mesalazine (100 mg kg^-1) significantly (p < 0.05) improved body weight and OSI and reduced macroscopic and microscopic scores. These treatments also significantly (p <0.05) recovered the increased levels of MDA and TNF-α as well as the decreased level of SOD in colon tissue. Crocin and mesalazine did not produce significant effects in intact rats. Based on the results, it is concluded that crocin and mesalazine produced protective effects on colon tissue via antioxidant and anti-inflammatory actions. In addition, a synergistic effect was observed between crocin and mesalazine in attenuating ulcerative colitis.

Protective effects of a novel probiotic strain, Lactococcus lactis ML2018, in colitis: in vivo and in vitro evidence

Multiple articles have confirmed that an imbalance of the intestinal microbiota is closely related to aberrant immune responses of the intestines and to the pathogenesis of inflammatory bowel diseases (IBDs).

Multi-Target Cinnamic Acids for Oxidative Stress and Inflammation: Design, Synthesis, Biological Evaluation and Modeling Studies

Inflammation is a complex phenomenon that results as a healing response of organisms to different factors, exerting immune signaling, excessive free radical activity and tissue destruction. Lipoxygenases and their metabolites e.g., LTB₄, are associated with allergy, cell differentiation and carcinogenesis. Lipoxygenase 12/15 has been characterized as a mucosal-specific inhibitor of IgA and a contributor to the development of allergic sensitization and airway inflammation. Development of drugs that interfere with the formation or effects of these metabolites would be important for the treatment of various diseases like asthma, psoriasis, ulcerative colitis, rheumatoid arthritis, atherosclerosis, cancer and blood vessel disorders. In this study we extended our previous research synthesizing a series of multi-target cinnamic acids from the corresponding aldehydes with suitable 4-OH/Br substituted phenyl acetic acid by Knoevenagel condensation. The final products 1i, 3i, 3ii, 4i, 6i, 6ii, and 7i were obtained in high yields (52–98%) Their structures were verified spectrometrically, while their experimentally lipophilicity was determined as R_M values. The novel derivatives were evaluated for their antioxidant activity using DPPH, hydroxyl radical, superoxide anion and ABTS^+•, anti-lipid peroxidation and soybean lipoxygenase inhibition assays. The compounds presented medium interaction with DPPH (30–48% at 100 µM). In contrast all the synthesized derivatives strongly scavenge OH radicals (72–100% at 100 µM), ABTS^+• (24–83% at 100 µM) and presented remarkable inhibition (87–100% at 100 µM) in linoleic acid peroxidation (AAPH). The topological polar surface of the compounds seems to govern the superoxide anion scavenging activity. Molecular docking studies were carried out on cinnamic acid derivative 3i and found to be in accordance with experimental biological results. All acids presented interesting lipoxygenase inhibition (IC₅₀ = 7.4–100 µM) with compound 3i being the most potent LOX inhibitor with IC₅₀ = 7.4 µM combining antioxidant activities. The antioxidant results support the LOX inhibitory activities. The recorded in vitro results highlight compound 3i as a lead compound for the design of new potent lipoxygenase inhibitors for the treatment of asthma, psoriasis, ulcerative colitis, rheumatoid arthritis, atherosclerosis, cancer and blood vessel disorders.

Nitric oxide in the gastrointestinal tract: opportunities for drug development

Nitric oxide (NO) plays important roles in gastrointestinal mucosal defence, as well as in the pathogenesis of several gastrointestinal diseases (e.g. irritable bowel syndrome and inflammatory bowel disease). The potent cytoprotective effects of NO have been demonstrated in a range of animal models. However, in some disease states, inhibition of NO synthesis is beneficial. Several attempts have been made to develop drugs for ulcerative and/or inflammatory disorders of the gastrointestinal tract, with varying degrees of success. Covalently linking a NO-releasing group to non-steroidal anti-inflammatory drugs or to drugs used in the treatment of inflammatory bowel disease and irritable bowel syndrome has shown some benefit, although no drug of this type has yet been fully developed. LINKED ARTICLES: This article is part of a themed section on Nitric Oxide 20 Years from the 1998 Nobel Prize. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.2/issuetoc.

Inhibition of dextran sodium sulfate-induced colitis in mice by baker's yeast polysaccharides

Most of the reported yeast polysaccharides are a mixture of chitin, β-glucan and mannoprotein, leading to different biological activities. Herein, we report the structures and the anti-inflammation of the purified baker's yeast polysaccharides (BBG1-BBG4). Experimental data indicated that BBG1 was a highly branched β-(1,6)-glucan linked to mannoprotein; BBG2 was a linear β-(1,3)-glucan; BBG3 and BBG4 were mixtures of a β-(1,6)-branched β-(1,3)-glucan and a linear β-(1,3)-glucan. Of these, BBG1 exhibited stronger inhibition of pro-inflammatory mediators of NO/iNOS, IL-6, IL-1β, etc. at protein and/or mRNA levels in LPS-stimulated RAW264.7 cells through inhibiting MAPK signalling pathways. Orally administered BBG1 and BBG2 significantly decreased the pro-inflammatory mediators of IL-6, iNOS and IL-1β at protein and/or mRNA levels, as well as colonic mucosal damage and macrophages infiltration in DSS-induced colitis mice. All these findings suggest that yeast polysaccharides have potentials as anti-inflammatory drugs or adjuvants in the intestinal inflammation therapy.

Effects of ZnO nanoparticles on intestinal function and structure in normal/high fat diet-fed rats and Caco-2 cells

Aim: The present study was carried out to determine the effects of ZnO nanoparticles (ZnO–NPs) on intestinal function and pathophysiological alteration. Materials & methods: ZnO–NPs were synthesized and their characterizations were performed using various techniques. The Wistar male rats fed with normal diet and/or high fat diet (HFD) for 8 weeks and then orally received ZnO–NPs (5, 50 and 100 mg/kg bodyweight) for 28 days. The oxidative stress (SOD, CAT, GPx), inflammatory (TNF-α, iNOS) and apoptosis pathways (Bcl2, Bax and p53) genes expression and protein levels were measured by real-time polymerase chain reaction and available kit, respectively. The activity of Caspase-3, antioxidant capacity, as well as inflammatory markers were determined. The histological alterations of the large and small intestine were also evaluated with haematoxylin and eosin (H&E) as well as TdT dUTP nick end labeling (TUNEL) assay. The biochemical factors, viability and antioxidant activity were also determined in Caco-2 cells. Results: It was found that the antioxidant enzymes activity and genes expression markedly increased, while inflammatory and apoptosis pathways and TNF-α levels significantly decreased in the intestine of HFD-fed rats treated with 5 mg/kg ZnO–NPs. Intestinal morphological changes were also restored by 5 mg/kg ZnO–NPs in HFD group. Conclusion: Treatment of rats with 50 and 100 mg/kg ZnO–NPs significantly induced intestinal injury, while treatment with 5 mg/kg ZnO nanoparticle normalized intestinal functions and structure. This study showed the synergistic effects of ZnO–NPs and HFD administration on liver enzyme, oxidative stress, apoptosis, inflammation, morphological changes and cell toxicity.

CCR6–CCL20 Axis in IBD: What Have We Learnt in the Last 20 Years?

CC chemokine receptor 6 (CCR6) and its specific partner CC chemokine ligand 20 (CCL20) are known to play a pivotal role in intestinal inflammation. CCR6-associated inflammatory bowel disease (IBD) is already at the forefront of experimental inflammatory disease models, being the subject of numerous analytical studies. IBD is associated with two sub phenotypes, Crohn’s disease (CD) and ulcerative colitis (UC). Both these disease entities produce potent immune dysregulation followed by intense tissue damage within the gut mucosal system, initiating symptoms that are severely debilitating. Multiple causative factors are said to be responsible for IBD, but direct immune dysfunction is kindled by overplay of innate and adaptive immune responses produced against the luminal contents through the weakened or leaky gut epithelial barrier. Once immune homeostasis is not achieved by endogenous protective mechanisms, the self-assertive adaptive immunity mobilizes its various T and B cell cohorts, initializing their immune mechanisms by deploying the immune cells towards the site of infection. CCR6 and its unique solitary ligand CCL20 are small protein molecules that are abundantly expressed by T and B lymphocytes and act as chemotactic immune-modulatory envoys that help in the deployment of the effector lymphocyte arm of the immune system and produce two directly opposing outcomes in IBD. This dichotomous immunity consists of either immune tolerance or inflammation which then develops into a chronic state, remaining unresponsive to inherent immunity or targeted clinical therapy. In this review, we have identified large numbers of experimental studies that have employed both mouse models and clinical subjects spanning a period of nearly two decades and we have clustered these into 13 different groups. This review will provide greater understanding of the CCR6–CCL20 axis in IBD and identify gaps in the literature that can be filled in the future.

Protective mechanisms of 6-gingerol in dextran sulfate sodium-induced chronic ulcerative colitis in mice

Ulcerative colitis (UC) is a relapsing and remitting inflammatory disease of the colon, with an increasing incidence worldwide. 6-Gingerol (6G) is a bioactive constituent of Zingiber officinale, which has been reported to possess various biological activities. This study was designed to evaluate the role of 6G in chronic UC. Chronic UC was induced in mice by three cycles of 2.5% dextran sulfate sodium (DSS) in drinking water. Each cycle consisted of 7 days of 2.5% DSS followed by 14 days of normal drinking water. 6G (100 mg/kg) and a reference anti-colitis drug sulfasalazine (SZ) (100 mg/kg) were orally administered daily to the mice throughout exposure to three cycles of 2.5% DSS. Administration of 6G and SZ significantly prevented disease activity index and aberrant crypt foci formation in DSS-treated mice. Furthermore, 6G and SZ suppresses immunoexpression of tumor necrosis factor alpha, interleukin-1β, inducible nitric oxide synthase, Regulated on activation, normal T cell expressed and secreted (RANTES), and Monocyte chemoattractant protein-1 (MCP-1) in the DSS-treated mice. 6G effectively protected against colonic oxidative damage by augmenting the antioxidant status with marked decrease in lipid peroxidation levels in DSS-treated mice. Moreover, 6G significantly inhibited nuclear factor kappa B (P65), p38, cyclooxygenase-2, and β-catenin whereas it enhanced IL-10 and adenomatous polyposis coli expression in DSS-treated mice. In conclusion, 6G prevented DSS-induced chronic UC via anti-inflammatory and antioxidative mechanisms and preservation of the Wnt/β-catenin signaling pathway.

Lactobacillus plantarum CQPC06 Activity Prevents Dextran Sulfate Sodium-Induced Colitis by Regulating the IL-8 Pathway

Lactobacillus plantarum CQPC06 (LP-CQPC06) is a newly discovered lactic acid bacterial strain. Here, the beneficial effects of this strain on C57BL/6J mice with dextran sulfate sodium-induced colitis were investigated. LP-CQPC06 was more resistant to gastric acid and bile salts than L. delbrueckii subsp. bulgaricus (LB). In the DSS-induced colitis mouse model, LP-CQPC06 treatment decreased the colon weight/length ratio and increased the colon length as compared to untreated mice with DSS-induced colitis. LP-CQPC06 also reduced the serum levels of interleukin 8 (IL-8), IL-1, tumor necrosis factor alpha, and macrophage inflammatory protein-1 alpha, as well as reducing levels of myeloperoxidase (MPO) and nitric oxide (NO) in the colon tissues of mice with DSS-induced colitis. In all cases, the effects of LP-CQPC06 were significantly stronger than those of LB. Quantitative polymerase chain reactions and western blots indicated that LP-CQPC06 increased the mRNA and protein expression levels of neuronal nitric oxide synthase, endothelial nitric oxide synthase, and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha, while decreasing the expression levels of inducible nitric oxide synthase, nuclear factor kappa-beta, C-X-C motif chemokine receptor 1 (CXCR1), and CXCR2. Thus, L. plantarum CQPC06 had a good protective effect against colitis in a mouse model via the IL-8 pathway. Therefore, L. plantarum CQPC06 might have potential uses as a probiotic for colonic protection.

PRACTICAL APPLICATION

In this study, a newly discovered lactic acid bacteria was investigated. This bacterial strain had a good prophylactic effect against colitis in a mouse model, and might have potential utility as a probiotic.

Decursinol Angelate Inhibits LPS-Induced Macrophage Polarization through Modulation of the NFκB and MAPK Signaling Pathways

Inflammation is considered the root cause of various inflammatory diseases, including cancers. Decursinol angelate (DA), a pyranocoumarin compound obtained from the roots of Angelica gigas, has been reported to exhibit potent anti-inflammatory effects. In this study, the anti-inflammatory effects of DA on the MAP kinase and NFκB signaling pathways and the expression of pro-inflammatory cytokines were investigated in phorbol 12-myristate 13-acetate (PMA)-activated human promyelocytic leukemia (HL-60) and lipopolysaccharide (LPS)-stimulated macrophage (Raw 264.7) cell lines. PMA induced the activation of the MAP kinase-NFκB pathway and the production of pro-inflammatory cytokines in differentiated monocytes. Treatment with DA inhibited the activation of MAP kinases and the translocation of NFκB, and decreased the expression and exogenous secretion of IL-1β and IL-6. Furthermore, LPS-stimulated Raw 264.7 cells were found to have increased expression of M1 macrophage-associated markers, such as NADPH oxidase (NOX) and inducible nitric oxide synthase (iNOS), and the M2 macrophage-associated marker CD11b. LPS also activated pro-inflammatory cytokines and Erk-NFκB. Treatment with DA suppressed LPS-induced macrophage polarization and the inflammatory response by blocking Raf-ERK and the translocation of NFκB in Raw 264.7 cells. Treatment with DA also inhibited the expression of pro-inflammatory cytokines, such as IL-1β and IL-6, NOX, and iNOS in Raw 264.7 cells. These results suggest that DA has the potential to inhibit macrophage polarization and inflammation by blocking the activation of pro-inflammatory signals. These anti-inflammatory effects of DA may contribute to its potential use as a therapeutic strategy against various inflammation-induced cancers.