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The intestinal mechanical barrier plays a key role in the pathogenesis of ulcerative colitis (UC). Our previous study showed keratin 1 (KRT1) was downregulated in UC, but the mechanism by which KRT1 affects the intestinal barrier remains unknown. To explore the mechanism of KRT1 in the intestinal barrier in UC. Colonic tissues were collected from 20 UC patients before and after mucosal healing (MH) and 15 healthy controls. The expression of KRT1 was measured by PCR, western blotting and immunohistochemistry (IHC). A dextran sulfate sodium (DSS)-induced colitis model was established in krt1 transgenic (TG) mice, and the mice were treated with methylprednisolone (MP) to explore the role of KRT1 in the intestinal barrier. Inflammation was evaluated through the DAI score, colon, spleen and H&E. The expression of KRT1 and tight junction (TJ) proteins in mouse was analysed by the same methods. The transcription and expression of KRT1 in UC was decreased and recovered after MH but did not reach the level of the healthy controls. Similar to the clinical results, the expression of krt1 was decreased in DSS-induced colitis and upregulated after MP. Moreover, the krt1 TG group exhibited less inflammation than wild-type (WT) group. The expression of Occludin and ZO-1 decreased after DSS induction, the decreases in Occludin and ZO-1 in the krt1 TG group were lower than WT group, which was significantly increased after MP, while the expression of Claudin-2 exhibited the opposite effect. Keratin 1 maintains the intestinal barrier by upregulating TJ proteins in UC.

Previous investigations reported that the imbalance of intestinal microflora may be the initiation and promotion factor in the pathogenesis of inflammatory bowel disease such as ulcerative colitis (UC). Glucocorticoid is a very important class of regulatory molecules in the body. The response of different individuals to glucocorticoids can be divided into glucocorticoid sensitive, glucocorticoid resistance and glucocorticoid dependence. We aimed to investigate the differences in intestinal microflora composition and related metabolic pathways in UC patients with these three different glucocorticoid response types. The whole genomic DNA was extracted from fecal specimens. High-throughput sequencing technology was used to analyze the fecal 16S rRNA genome of UC patients with different glucocorticoid response types, and functional prediction was performed by PICRUSTs software. The results showed that the intestinal microflora of the three groups were mainly composed of Firmicutes, Proteobacteria and Bacteroidetes. Although the species abundance and diversity of intestinal microflora in UC patients differed little among the three groups, the composition of intestinal microflora showed significant heterogeneity, which directly led to differences in the function of intestinal microbiota of UC patients with different glucocorticoid responses. Furthermore, of the 240 pathways, “PANTO-PWY: phosphopantothenate biosynthesis I”, “COA-PWY-1: coenzyme A biosynthesis II (mammalian)” and “PWY-4242: pantothenate and coenzyme A biosynthesis III” were significantly different in the three groups. These results indicate that UC patients with different glucocorticoids response types have different bacterial compositions and functions, which lays a foundation for further study of glucocorticoid resistance in UC patients.

UC is a chronic inflammatory disease of the colonic mucosa and lacks effective treatments because of unclear pathogenesis. Excessive apoptosis of IECs damages the intestinal epithelial barrier and is involved in the progression of UC, but the mechanism is unknown. HSPs are important in maintaining homeostasis and regulate apoptosis through the mitochondrial pathway. In our previous studies, HSF2, an important regulator of HSPs, was highly expressed in UC patients and negatively correlated with inflammation in mice and IECs. Therefore, we hypothesized that HSF2 may protect against intestinal mucositis by regulating the apoptosis of IECs. In this study, a DSS-induced colitis model of hsf2−/− mice was used to explore the relationship between HSF2 and apoptosis in IECs for the first time. The expression of HSF2 increased in the WT + DSS group compared with that in the WT + H2O group. Moreover, the extent of apoptosis was more severe in the KO + DSS group than in the WT + DSS group. The results showed that HSF2 was negatively correlated with apoptosis in vivo. The expression of HSF2 in Caco-2 cells was changed by lentiviral transfection, and the expression of Bax, cytoplasmic Cyto-C, Cleaved Caspase-9 and Cleaved Caspase-3 were negatively correlated with the different levels of HSF2. These results suggest that HSF2 negatively regulates apoptosis of IECs through the mitochondrial pathway. This may be one of the potential mechanisms to explain the protective role of HSF2 in UC.

Background Ulcerative colitis (UC) is one of the primary types of inflammatory bowel disease (IBD), the occurrence of which has been increasing worldwide. Although IBD is an intensively studied human microbiome-associated disease, research on Chinese populations remains relatively limited, particularly on the mucosal microbiome. The present study aimed to analyze the changes in the mucosal microbiome associated with UC from the perspectives of medical ecology and complex network analysis. Results In total, 56 mucosal microbiome samples were collected from 28 Chinese UC patients and their healthy family partners, followed by amplicon sequencing. Based on sequencing data, we analyzed species diversity, shared species, and inter-species interactions at the whole community, main phyla, and core/periphery species levels. We identified four opportunistic “pathogens” (i.e., Clostridium tertium, Odoribacter splanchnicus, Ruminococcus gnavus, and Flavonifractor plautii) with potential significance for the diagnosis and treatment of UC, which were inhibited in healthy individuals, but unrestricted in the UC patients. In addition, we also discovered in this study: (i) The positive-to-negative links (P/N) ratio, which measures the balance of species interactions or inhibition effects in microbiome networks, was significantly higher in UC patients, indicating loss of inhibition against potentially opportunistic “pathogens” associated with dysbiosis. (ii) Previous studies have reported conflicting evidence regarding species diversity and composition between UC patients and healthy controls. Here, significant differences were found at the major phylum and core/periphery scales, but not at the whole community level. Thus, we argue that the paradoxical results found in existing studies are due to the scale effect. Conclusions Our results reveal changes in the ecology and network structure of the gut mucosal microbiome that might be associated with UC, and these changes might provide potential therapeutic mechanisms of UC. The four opportunistic pathogens that were identified in the present study deserve further investigation in future studies.

Summary Liver diseases affect millions of people worldwide. In most developed countries, the incidence of viral hepatitis is waning as a result of modern advances in disease prevention, diagnosis, and therapies. Expanded programmes for systematic immunisation against hepatitis B virus have also significantly brought down the number of new cases in many countries, including China. In contrast, with the improvement in living standards, the prevalence of metabolic liver diseases including non-alcoholic fatty liver disease and alcohol-related liver disease is set to rise, ultimately leading to more cases of end-stage liver diseases (liver failure, cirrhosis, and liver cancer). Over the past 30 years, visionary governments of major nations have provided strong incentives for basic/clinical research, vaccination programmes, and drug discovery and development in the field of hepatology. To get rid of her unflattering title as the "leader in liver diseases", China has also made a serious effort to initiate nationwide preventive measures for liver diseases, global partnerships, and mentoring programmes for young hepatologists. Instrumental to such progress is the continuous support of the National Natural Science Foundation of China (NSFC), which has helped hepatology to thrive in virtually all research directions within the country. In this article, we seek to provide stimulating glimpses into the evolving liver disease epidemiology, institutional research profiles, funding landscape, and drug development trends in China, with an attempt to compare her status and achievements with those of the United States, European countries, and Japan.

Obesity and type 2 diabetes mellitus (T2DM) are associated with changes in the gut bacterial composition, but little is known about the role of the viral community (virome) in disease development. This study aims to characterize the gut virome alterations in obese subjects with or without T2DM.There were 128 obese subjects (body mass index ≥28 kg/mObese subjects, especially those with T2DM (ObT2), had a decreased gut viral richness and diversity compared with lean controls in the Hong Kong cohort (P.05), while no significant differences were observed in the Kunming cohort. Eleven viruses, including Escherichia phage, Geobacillus phage, and Lactobacillus phage were enriched in obese subjects (q.1). Besides, 17 differentially abundant viruses were identified between ObT2 and lean controls (q.1). Further ecologic analysis revealed that intensive transkingdom correlations between viruses and bacteria observed in lean controls were significantly decreased in ObT2 subjects (P.001).Obesity is characterized by altered viral taxonomic composition and weakened viral-bacterial correlations compared with lean controls. Obesity accompanied with T2DM may aggravate the obesity-associated virus signatures, signifying that the gut virome may play an important role in the development of obesity and T2DM. Geographic factors also contributed to the variations of gut virome in obesity and T2DM.

Background Cytomegalovirus (CMV) infection can significantly complicate and worsen the condition of acute severe ulcerative colitis (UC) patients. We aimed to explore the predictive risk factors to prevent and identify CMV infection at an early stage in acute UC patients. Methods A total of 115 moderate-to-severe active UC patients from 17 hospitals throughout China were enrolled. Active CMV infection was diagnosed by one of the following: CMV pp65 antigens, CMV IgM antibodies or CMV DNA. We identified the independent risk factors by multivariate analyses. Results A total of 64 of 115 active UC patients had active CMV infection. Compared to the non-CMV-infected patients, the CMV-infected patients had a tendency to be male and to exhibit abdominal pain; fever; oral ulcers; eosinopenia; low albumin, immunoglobulin (Ig) A, IgM, and IgG levels; increased high-sensitivity C-reactive protein (hsCRP) levels; hyponatremia; pancolonic lesions; initial onset type; severe activity; and glucocorticoid (high-dose) and immunosuppressive agent use (P P P = 0.04) were independent risk factors for CMV infection. A decrease eosinophil and albumin levels were risk factors for CMV infection. With every 0.1*10^9/L decrease in the peripheral blood eosinophil level or 1 g/L decrease in the serum albumin level, the risk for CMV infection in UC patients increased by 5.21-fold (1/0.192) or 1.19-fold (1/0.839), respectively. Conclusions High-dose glucocorticoid and immunosuppressive agent treatment significantly increase the risk of CMV infection, and correcting eosinopenia and low albumin levels may help prevent CMV infection in UC patients.

Background: Mucosal healing(MH) is a treatment goal in ulcerative colitis (UC). Our previous studies showed heat shock transcription factor 2 (HSF2) was positively correlated with the activity of U...

Background Cytomegalovirus (CMV) infection can significantly complicate and worsen the condition of acute severe ulcerative colitis (UC) patients. We aimed to explore the predictive risk factors to prevent and identify CMV infection at an early stage in acute UC patients. Methods A total of 115 moderate-to-severe active UC patients from 17 hospitals throughout China were enrolled. Active CMV infection was diagnosed by one of the following: CMV pp65 antigens, CMV IgM antibodies or CMV DNA. We identified the independent risk factors by multivariate analyses. Results A total of 64 of 115 active UC patients had active CMV infection. Compared to the non-CMV-infected patients, the CMV-infected patients had a tendency to be male and to exhibit abdominal pain; fever; oral ulcers; eosinopenia; low albumin, immunoglobulin (Ig)A, IgM, and IgG levels; increased high-sensitivity C-reactive protein (hsCRP) levels; hyponatremia; pancolonic lesions; initial onset type; severe activity; and glucocorticoid (high-dose) and immunosuppressive agent use (P

Inflammatory bowel disease (IBD) shares many clinical, endoscopic, and histologic aspects of enteritis and colitis of infectious etiologies, including bacteria, viruses, fungi, and parasites. Patients with infectious enteritis and colitis often have a history of consumption of unclean drinks or foods, especially in the epidemic or endemic area. Patients with acute episodes often present fever, abdominal pain, diarrhea, mucus, and bloody bowel movements. In most cases, infectious enteritis and colitis are self-limited, lasting several days to several weeks. Stool examination often shows red blood cells and white blood cells. However, stool microbiological examination, albeit useful, is only able to identify pathogen(s) in less than 50% of patients. During the acute phase of infectious enteritis or colitis, upper and lower endoscopy usually provide limited value in the diagnosis and differential diagnosis. However, the endoscopy is required, if the symptom persists beyond 4 weeks. Endoscopic features of infectious bowel diseases are mostly nonspecific. However, there are some characteristic endoscopic features in some infectious bowel diseases, such as intestinal tuberculosis. These agents may also cause superimposed or opportunistic infection to underlying IBDs.

Bacterial DNA (bacDNA) is frequently found in serum of patient with ulcerative colitis (UC) and Crohns disease, even blood bacterial culture is negative. How bacDNA evades immune elimination and is translocated into blood remain unclear. Here, we showed that bacDNA avoids elimination and disables bacteria-killing function of antimicrobial peptide LL-37 (Cramp in mice) by forming complex with LL-37, which is inducible after culture with bacteria or bacterial products. Elevated LL-37-bacDNA complex was found in plasma and lesions of patients with UC. LL-37-bacDNA promoted inflammation by inducing Th1, Th2 and Th17 differentiation and activating toll-like receptor-9 (TLR9). The complex also increased paracellular permeability, which possibly combines its inflammatory effects to promote local damage and bacDNA translocation into blood. Cramp-bacDNA aggravated mouse colitis severity while interference with the complex ameliorated the disease. The study identifies that inflammatogenic bacDNA utilizes LL-37 as a vehicle for blood translocation and to evade immune elimination. Additionally, bacteria may make a milieu by releasing bacDNA to utilize and resist host antimicrobial peptides as a trojan horse.

BackgroundNeutrophils are accumulated in inflamed mucosa of IBD and play an important role in the pathogenesis. CD177 is expressed in neutrophils specifically and upregulated during inflammation. However, the role of CD177+ neutrophils in pathogenesis of IBD remains elusive.Materials and methodsExpression of CD177 was analysed in peripheral blood and intestinal mucosa from patients with IBD using quantitative RT-PCR, flow cytometry and immunohistochemistry. CD177+ and CD177− neutrophils were isolated to determine gene differences by RNA sequencing. Colitis was established in CD177−/− and wild-type mice in response to dextran sulfate sodium (DSS) insults to determine the role of CD177+ neutrophils in IBD.ResultsCD177+ neutrophils were markedly increased in peripheral blood and inflamed mucosa from patients with active IBD compared with healthy controls. RNA sequencing revealed that differential gene expression between CD177+ and CD177− neutrophils from patients with IBD was associated with response to bacterial defence, hydrogen peroxide and reactive oxygen species (ROS). CD177+ neutrophils produced lower levels of proinflammatory cytokines (ie, interferon-γ, interleukin (IL)-6, IL-17A), but higher levels of IL-22 and transforming growth factor-β, and exhibited increased bactericidal activities (ie, ROS, antimicrobial peptides, neutrophil extracellular trap) compared with CD177− subset. CD177−/− mice developed more severe colitis on DSS insults compared with wild-type mice. Moreover, CD177 deficiency led to compromised intestinal barrier and impaired antibacterial immunity through decreased production of IL-22 by CD177− neutrophils.ConclusionsCD177+ neutrophils represent functionally activated population and play a protective role in IBD through increased bactericidal activity and IL-22 production. Targeting CD177+ neutrophils may be beneficial for treatment of IBD.

Ulcerative colitis (UC) is a major type of inflammatory bowel disease (IBD) and significantly impacts patient quality of life. Previous research revealed that the guanylate cyclase-C (GC-C) signaling pathway is associated with the severity of UC. We aimed to investigate the effect of the GC-C agonist, guanylin (Gn), on inflammatory injury in mice with colitis. An experimental UC model was established in Balb/c mice. Mesalamine served as a positive control. The Gn overexpression vector was administered once per day for 1 week. Intestinal permeability of the mice was measured using fluorescein isothiocyanate-dextran after the treatment. Histopathologic grading was estimated to assess the inflammatory injury of the colon. The expression level of crucial mediators of the GC-C signaling pathway (Gn, Ugn and GC-C) and tight junction proteins (occludin, claudin-1 and ZO-1) was measured in the colon. Additionally, the level of pro-inflammatory cytokines (IL-8 and TNF-α) in serum was measured. After injecting the UC mice with the Gn overexpression vector, the body weight increased, and the frequency of loose stools and bloody stools was decreased. Intestinal permeability and histopathologic score were significantly reduced (P

Butyrate-induced autophagy and anti-inflammatory effects of IECs plays an important role in UC. HSP has been proved to be associated with autophagy. HSF2, as an important regulator of HSP, has been determined to be highly expressed in UC. This study was designed to elucidate the relationship between HSF2, butyrate and epithelial autophagy and the potential mechanism of HSF2-related autophagy in UC. The autophagy levels and HSF2 expression in intestinal mucosa were increased in UC patients compared to controls. In DSS colitis models, hsf2-/- mice exhibited more severe intestinal inflammation and lower autophagy levels than wild-type mice. HSF2 expression could be induced by sodium butyrate and LPS as a dose-response relationship in HT-29 cells, epigenetically via increasing histone acetylation levels at the promoter region by sodium butyrate. Autophagy induced by sodium butyrate was promoted by overexpression HSF2 in HT-29 cells. Moreover, overexpression HSF2 decreased the expression and phosphorylation levels of PI3K, Akt and mTOR induced by sodium butyrate. HSF2 might induced by sodium butyrate and inflammation and played protective roles in UC by enhancing autophagy of IECs. This indicated that HSF2 may be a critical target for autophagy modulation and a new potential therapeutic target in UC.

The dysbiosis of the gut microbiome associated with ulcerative colitis (UC) has been extensively studied in recent years. However, the question of whether UC influences the spatial heterogeneity of the human gut mucosal microbiome has not been addressed. Spatial heterogeneity (specifically, the inter-individual heterogeneity in microbial species abundances) is one of the most important characterizations at both population and community scales, and can be assessed and interpreted by Taylor’s power law (TPL) and its community-scale extensions (TPLEs). Due to the high mobility of microbes, it is difficult to investigate their spatial heterogeneity explicitly; however, TPLE offers an effective approach to implicitly analyze the microbial communities. Here, we investigated the influence of UC on the spatial heterogeneity of the gut microbiome with intestinal mucosal microbiome samples collected from 28 UC patients and healthy controls. Specifically, we applied Type-I TPLE for measuring community spatial heterogeneity and Type-III TPLE for measuring mixed-species population heterogeneity to evaluate the heterogeneity changes of the mucosal microbiome induced by UC at both the community and species scales. We further used permutation test to determine the possible differences between UC patients and healthy controls in heterogeneity scaling parameters. Results showed that UC did not significantly influence gut mucosal microbiome heterogeneity at either the community or mixed-species levels. These findings demonstrated significant resilience of the human gut microbiome and confirmed a prediction of TPLE: that the inter-subject heterogeneity scaling parameter of the gut microbiome is an intrinsic property to humans, invariant with UC disease.

Living in an urban environment may increase the risk of developing inflammatory bowel disease (IBD). It is unclear if this observation is seen globally. We conducted a population-based study to assess the relationship between urbanization and incidence of IBD in the Asia-Pacific region. Newly diagnosed IBD cases between 2011 and 2013 from 13 countries or regions in Asia-Pacific were included. Incidence was calculated with 95% confidence interval (CI) and pooled using random-effects model. Meta-regression analysis was used to assess incidence rates and their association with population density, latitude, and longitude. We identified 1175 ulcerative colitis (UC), 656 Crohn’s disease (CD), and 37 IBD undetermined (IBD-U). Mean annual IBD incidence per 100 000 was 1.50 (95% CI: 1.43–1.57). India (9.31; 95% CI: 8.38–10.31) and China (3.64; 95% CI, 2.97–4.42) had the highest IBD incidence in Asia. Incidence of overall IBD (incidence rate ratio [IRR]: 2.19; 95% CI: 1.01–4.76]) and CD (IRR: 3.28; 95% CI: 1.83–9.12) was higher across 19 areas of Asia with a higher population density. In China, incidence of IBD (IRR: 2.37; 95% CI: 1.10–5.16) and UC (IRR: 2.63; 95% CI: 1.2–5.8) was positively associated with gross domestic product. A south-to-north disease gradient (IRR: 0.94; 95% CI: 0.91–0.98) was observed for IBD incidence and a west-to-east gradient (IRR: 1.14; 95% CI: 1.05–1.24) was observed for CD incidence in China. This study received IRB approval. Regions in Asia with a high population density had a higher CD and UC incidence. Coastal areas within China had higher IBD incidence. With increasing urbanization and a shift from rural areas to cities, disease incidence may continue to climb in Asia.

Cystic fibrosis (CF) is a hereditary disease that is characterized by defective mucociliary clearance, airway obstruction, chronic infection, and persistent inflammation. Cystic fibrosis pulmonary exacerbation (CFPE) majorly causes the morbidity of CF patients. Although CF has been demonstrated to change the composition of lung microbial community, previous studies have not made efforts to study the differences in the mechanism of assembly and diversity maintenance of lung microbial community in CF patients. In this study, we applied the neutral theory of biodiversity to comparatively investigate the assembly and diversity maintenance of the lung microbial community before and after the antibiotic treatment by reanalyzing the dataset from Fodor et al's study. We found that no one sample in the lung microbial communities of the sputum samples of Exacerbation group, nor those of End-of-treatment group satisfied the predictions of neutral model, suggesting that the neutral-process does not dominate in CF patients before and after antibiotic treatments. By comparing the biodiversity parameter between Exacerbation and End-of-treatment group, we found that the former had the significantly higher biodiversity, but the change in diversity parameter is slight and the P value is close to.05 (P value = .41). Therefore, our second finding is that although CFPE may increase the biodiversity of lung microbial community, the change is not essential.

Withaferin A (WA) is an active steroidal lactone derived from the herbal plant Withania somnifera, which exhibits antitumor activity with reactive oxygen species (ROS) modulating in a variety of cancer models, such as breast cancer, lung cancer and pancreatic cancer. However, to the best of our knowledge, the direct effect and mechanism of WA on CRC cells has not been previously determined. The present study investigated the anti-tumor effects of WA on CRC cells in vitro, and explored the mechanisms of action. The flow cytometry was applied for detecting the accumulation of ROS with the treatment of withaferin A. We performed the flow cytometry and western blot to evaluate the withaferin A induced apoptosis and cell cycle arrest in human colon cancer cells. And to verify the ROS accumulation induced mitochondrial dysfunction after the treatment of withaferin A, fluorescence microscope and western blot were applied. WA exerted a dose-dependent cytotoxic effect on HCT-116 and RKO cells. The effect was associated with ROS-mediated cell cycle arrest and the expression of apoptotic proteins. In addition, WA promoted ROS production and decreased mitochondrial membrane potential accompanying with mitochondrial dysfunction. Taken together, these results strongly indicated that WA directly inhibits cell growth and induces apoptosis in CRC cells through ROS-mediated mitochondrial dysfunction and JNKs pathway, and WA may be a promising potential candidate for therapeutic application of CRC.

Inflammatory bowel disease (IBD) is an immunologically mediated disease and may be caused by abnormal immunological response to gut microbes. Although several studies on the ecological changes associated with IBD, such as community diversities, were reported, no previous studies have investigated the changes in the spatial heterogeneity and the mechanism of community assembly of the gut microbiota associated with IBD. In the present study, we first applied the Taylor’s power law extensions to compare the community spatial heterogeneity between the gut microbial communities of the IBD patients and those of the healthy individuals. We found that the community spatial heterogeneity of gut microbiota in IBD patients is slightly lower than in the healthy individuals. This finding suggests that IBD may lower the spatial heterogeneity of gut microbiota, possibly via lowering the abundance of dominant species. We further applied the neutral theory of biodiversity to comparatively investigate the community assembly and diversity maintenance of the gut microbiota with and without IBD, and our application suggested that deterministic factors such as host immunity should be dominant forces shaping gut microbiota assembly, and diseases such as IBD may not be strong enough to change the trend set by the deterministic host factors.

Inflammatory bowel disease (IBD) is the result of a chronic intestinal inflammatory response which usually occurred in colon and small intestine. Keratins constitute the intermediate filament cytoskeleton in all epithelia. The present study was intended to explore the role of Keratin 1 (KRT1) in the progress of IBD. In normal intestinal tissue, the expression of KRT1 was detected by RT-PCR and Western blot. The levels of KRT1 protein significantly decreased in serum samples of IBD patients as compared with sera of healthy controls. Immunohistochemistry revealed that the expression of KRT1 decreased in various intestinal diseases, especially in Crohn's disease and ulcerative colitis. Furthermore, down-regulated KRT1 was correlated with the severity of IBD. The overexpression of KRT1 maintained epithelial barrier in Caco-2 cells after IL-1β treatment. Furthermore, IL-1β-induced disruption of tight junction became significantly attenuated in KRT1 over-expressing Caco-2 cells as compared with control cells. Thus, KRT1 played an important role of maintaining epithelial barrier and its down-regulation in intestinal tissue was correlated with the progression of IBD.

The transmembrane receptor guanylate cyclase-C (GC-C) signaling pathway has been implicated in several gastrointestinal disorders. Activation of GC-C via guanylin (Gn) and uroguanylin (Ugn) regulates intestinal fluid and electrolyte homeostasis. However, how it regulates the pathogenesis of inflammatory bowel disease (IBD) is still unclear. Here, we investigated the activation of GC-C signaling in ulcerative colitis (UC) of different clinical severities. A total of 60 UC patients and 20 normal controls were recruited. Evaluation of the UC disease activity index (DAI) was performed using a modified Mayo scoring system. The expression of GC-C, Gn and Ugn in the colonic mucosa was measured by quantitative real-time PCR and Western blot. We found that the UC patients had significantly lower expression of GC-C, Gn and Ugn than the controls. Furthermore, there were significant differences for GC-C, Gn and Ugn expression for the UC groups of Grade 1, 2 and 3 and their expression levels were reduced with increases in their DAI. Taken together, our results demonstrate that GC-C, Gn and Ugn are downregulated in UC and this downregulation is more significant with aggravation of the clinical condition. Therefore, the GC-C signaling pathway may be implicated in the progression of UC.

Background The aim of this study was to examine environmental factors associated with inflammatory bowel disease (IBD) in Yunnan Province, a southwestern highland region of China. Methods In this nested case-control study, newly diagnosed ulcerative colitis (UC) cases in 2 cities in Yunnan Province and Crohn’s disease (CD) cases in 16 cities in Yunnan Province were recruited between 2008 and 2013. Controls were matched by geography, sex and age at a ratio of 1:4. Data were collected using the designed questionnaire. Conditional logistic regression models were used to estimate adjusted odds ratios (ORs). Results A total of 678 UC and 102 CD cases were recruited. For UC, various factors were associated with an increased risk of developing UC: dietary habits, including frequent irregular meal times; consumption of fried foods, salty foods and frozen dinners; childhood factors, including intestinal infectious diseases and frequent use of antibiotics; and other factors, such as mental labor, high work stress, use of non-aspirin non-steroidal anti-inflammatory drugs and allergies (OR > 1, p < 0.05). Other factors showed a protective effect: such as consumption of fruits, current smoking, physical activity, and drinking tea (OR < 1, p < 0.05). For CD, appendectomy and irregular meal times increased the disease risk (OR >1, p < 0.05), whereas physical activity may have reduced this risk (OR < 1, p < 0.05). Conclusions This study is the first nested case-control study to analyze the association between environmental factors and IBD onset in a southwestern highland region of China. Certain dietary habits, lifestyles, allergies and childhood factors may play important roles in IBD, particularly UC.

OBJECTIVE 6-mercaptopurine (6-MP) is efficacious in the treatment of inflammatory bowel disease (IBD). However, about one-third of patients respond poorly to therapy. This study aimed to characterize the inherent differences in 6-MP transport that may contribute to the differences in treatment responses.

Divalent metal-ion transporter 1 (DMT1) has been found to play an important role in the iron metabolism and hemogenesis. However, little is known about the potential role of DMT1 in the pathogenesis of anemia from patients with inflammatory bowel disease (IBD). Herein, we investigated expression of DMT1 in the intestinal mucosa by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry and found that DMT1 was significantly decreased in the inflamed mucosa of active IBD patients compared with that in those patients at remission stage and healthy controls. To further study the mechanism, we cultured HCT 116 cell line in vitro. Expression of DMT1 in HCT116 was demonstrated to be markedly decreased under stimulation with TNF for 24 and 48 h, while JNK inhibitor (JNK-IN-7) could significantly reverse the decrease. Interestingly, anti-TNF therapy successfully improved anemia in clinical responsive Crohn’s disease patients and DMT1 was found to be markedly up-regulated in intestinal mucosa. Taken together, our studies demonstrate that decreased expression of DMT1 in intestinal mucosa leads to compromised absorption and transportation of iron and that blockade of TNF could rescue anemia and promote DMT1 expression in gut mucosa. This work provides a therapeutic approach in the management of anemia in IBD.

Background and aims The morbidity of ulcerative colitis (UC) is increasing in China every year. In addition, there is a lack of accurate diagnostic indices with which to evaluate the activity of the disease. The aim of this study was to identify UC-associated proteins as biomarkers for the diagnosis, and objective assessment of disease activity. Methods Differential expression of serum proteins from UC patients compared to normal controls was analyzed by two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS). The expression of heat shock factor 2(HSF2)in colonic mucosa in Crohn's disease, Behcet's disease, ulcerative colitis, intestinal tuberculosis, infective enteritis, intestinal lymphoma, and normal controls was investigated by immunohistochemistry (IHC). The expression of the HSF2 in colonic mucosa of UC subjects with varying severity of disease was measured by real time-PCR and Western Blots. The expression of HSF2 was inhibited by HSF2 small interfering RNA (siRNA) transfection in Caco-2 cells. The concentrations of HSF2, IL-1β, and TNF-α in serum and IL-1β, and TNF-α in the supernatants of transfected Caco-2 cells were determined by ELISA. Results HSF2 was differentially expressed in UC patients compared to normal controls. HSF2 expression was significantly higher in the intestinal mucosa of UC patients compared to other six groups. The results of immunohistochemistry, real time-PCR, Western Blots, and ELISA showed that the expression of HSF2 increased in parallel with the severity of UC. The serum concentration of HSF2 also positively correlated with levels of IL-1β and TNF-α. After down-regulation expression of HSF2 in Caco-2 cells by RNA interference, the productions of IL-1β and TNF-α stimulated by lipopolysaccharide (LPS) increased dramatically. Conclusions HSF2 appears to be a potential novel molecular marker for UC activity, and may provide a basis for studies on the pathogenesis and novel therapeutic targets for UC.

To evaluate potential risk factors in the development of ulcerative colitis (UC) in China.A total of 1308 patients with UC and 1308 age-matched and sex-matched controls were prospectively studied in China. The UC cases were collected from 17 hospitals in China from April 2007 to April 2010. Uniform questionnaires were designed to investigate risk factors including smoking, appendectomy, stress, socio-economic conditions, nonsteroidal anti-inflammatory drugs (NSAIDs), oral contraceptives, diet, breastfeeding, infections and family sanitary conditions. Group comparisons by each factor were done using simple logistic regression analysis. Conditional logistic regression was used for multivariate analysis.By univariate analysis, the variables predictive of UC included feeling stress, light and heavy alcoholic drinking, spicy food, sugar consumption and infectious diarrhea, while heavy tea intake and tap water consumption were protective against UC. On multivariate analysis, the protective factor for UC was tap water consumption [odds ratios (OR) = 0.424, 95%CI: 0.302-0.594, P0.001]; while the potential risk factors for UC were heavy sugar consumption (OR = 1.632, 95%CI: 1.156-2.305, P0.001), spicy food (light intake: OR = 3.329, 95%CI: 2.282-4.857, P0.001; heavy intake: OR = 3.979, 95%CI: 2.700-5.863, P0.001), and often feeling stress (OR = 1.981, 95%CI: 1.447-2.711, P0.001). Other factors, such as smoking habit, appendectomy, breastfeeding, a history of measles, rural or urban residence, education, oral contraceptives, and NSAID use have not been found to have a significant association with the development of UC in the present study.Our study showed tap water consumption was a protective factor for UC, while spicy food, heavy sugar consumption and often feeling stress were risk factors for UC in this Chinese population.