Human intestinal microbiota composition is associated with local and systemic inflammation in obesity.

OBJECTIVE: Intestinal microbiota have been suggested to contribute to development of obesity, but the mechanism remains elusive. We relationship between microbiota composition, intestinal permeability, inflammation in non-obese and obese subjects. DESIGN AND METHODS: Fecal microbiota composition of 28 subjects (BMI 18.6-60.3kg/m2 ) was analyzed phylogenetic profiling microarray. Fecal calprotectin and plasma C- protein levels were determined to evaluate intestinal and systemic Furthermore, HbA1c , and plasma levels of transaminases and lipids were Gastroduodenal, small intestinal, and colonic permeability were assessed multi-saccharide test. RESULTS: Based on microbiota composition, the population segregated into two clusters with predominantly obese (15/19) exclusively non-obese (9/9) subjects. Whereas intestinal permeability differ between clusters, the obese cluster showed reduced bacterial decreased Bacteroidetes/Firmicutes ratio, and an increased abundance of pro-inflammatory Proteobacteria. Interestingly, fecal calprotectin was detectable in subjects within the obese microbiota cluster (n=8/19, Plasma C-reactive protein was also increased in these subjects correlated with the Bacteroidetes/Firmicutes ratio (rs =-0.41, p=0.03). CONCLUSIONS: Intestinal microbiota alterations in obese subjects are with local and systemic inflammation, suggesting that the obesity- microbiota composition has a pro-inflammatory effect

Dutch juvenile idiopathic arthritis patients, carers and clinicians create a research agenda together following the James Lind Alliance method: A study protocol

Background: Research on Juvenile Idiopathic Arthritis (JIA) should support patients, caregivers/parents (carers) and clinicians to make important decisions in the consulting room and eventually to improve the lives of patients with JIA. Thus far these end-users of JIA-research have rarely been involved in the prioritisation of future research. Main body: Dutch organisations of patients, carers and clinicians will collaboratively develop a research agenda for JIA, following the James Lind Alliance (JLA) methodology. In a 'Priority Setting Partnership' (PSP), they will gradually establish a top 10 list of the most important unanswered research questions for JIA. In this process the input from clinicians, patients and their carers will be equally valued. Additionally, focus groups will be organised to involve young people with JIA. The involvement of all contributors will be monitored and evaluated. In this manner, the project will contribute to the growing body of literature on how to involve young people in agenda setting in a meaningful way. Conclusion: A JIA research agenda established through the JLA method and thus co-created by patients, carers and clinicians will inform researchers and research funders about the most important research questions for JIA. This will lead to research that really matters

Regulation and characteristics of vascular smooth muscle cell phenotypic diversity

Vascular smooth muscle cells can perform both contractile and synthetic functions, which are associated with and characterised by changes in morphology, proliferation and migration rates, and the expression of different marker proteins. The resulting phenotypic diversity of smooth muscle cells appears to be a function of innate genetic programmes and environmental cues, which include biochemical factors, extracellular matrix components, and physical factors such as stretch and shear stress. Because of the diversity among smooth muscle cells, blood vessels attain the flexibility that is necessary to perform efficiently under different physiological and pathological conditions. In this review, we discuss recent literature demonstrating the extent and nature of smooth muscle cell diversity in the vascular wall and address the factors that affect smooth muscle cell phenotype. (Neth Heart J 2007;15:100-8.17612668

Smoothelin in vascular smooth muscle cells

Smoothelin-A and -B have only been found in fully differentiated contractile smooth muscle cells. They are increasingly used to monitor the smooth muscle cell differentiation process to a contractile or synthetic phenotype. Vascular-specific smoothelin-B is the first smooth muscle cell marker that disappears when vascular tissues are compromised, for example, in atherosclerosis or restenosis. Recently obtained data show that smoothelin deficiency results in a considerable loss of contractile potential and hence in impaired smooth muscle function and suggest that smoothelins are part of the contractile apparatus

Wnt/frizzled signalling modulates the migration and differentiation of immortalized cardiac fibroblasts

The Wnt/frizzled (Fzd) signal transduction cascade has been implicated in the proliferation, differentiation, and migration of many cell types, but the role of this pathway in cardiac fibroblast differentiation is not known. Our lab previously showed an up-regulation of Fzd-1 and -2 expression in myofibroblasts after myocardial infarction (MI), indicating a potential role for the Fzd receptor in fibroblast-myofibroblast differentiation. The present study was performed to further define the role of specific Wnt and Fzd proteins in the proliferation, migration, and differentiation of cardiac fibroblasts. Because primary fibroblasts become senescent after a few passages and are difficult to transfect, we immortalized rat cardiac fibroblasts with telomerase [cardiac fibroblasts immortalized with telomerase (CFIT)]. Proliferation of CFIT was not significantly influenced by Wnt/Fzd signalling. The migration, however, was attenuated by all Wnt/Fzd combinations tested. Also, specific Wnt/Fzd combinations modulated the expression of the following myofibroblast markers: collagen I alpha 1, collagen III, fibronectin and its splice variants, and alpha-smooth muscle actin. The results indicate that myofibroblast migration and differentiation, but not proliferation, can be modulated by interventions in Wnt/Fzd signalling. Therefore, Wnt/Fzd signalling may serve as a novel therapeutic target to ameliorate wound healing after MI

Novel evidence for chronic exposure to endotoxin in human nonalcoholic steatohepatitis.

BACKGROUND: Endotoxin is hypothesized to play an important role in the activation of inflammatory pathways associated with nonalcoholic steatohepatitis (NASH). However, demonstration of hepatic endotoxin exposure is challenging due to the inaccessibility of the portal circulation. Furthermore, reliable measurement of the relatively low endotoxin levels in plasma of patients with liver disease and subsequent interpretation remain difficult. GOALS: In this study, we used the EndoCab assay that measures endogenous antibodies to the core region of endotoxin to estimate hepatic endotoxin exposure over time. STUDY: IgG levels against endotoxin were measured in peripheral plasma obtained from 21 severely obese patients with NASH and 9 severely obese patients with healthy livers. RESULTS: Plasma IgG levels against endotoxin were significantly elevated in patients with NASH compared with patients with healthy livers (48+/-63 GMU/mL vs. 10+/-13 GMU/mL). Moreover, these IgG levels progressively increased with NASH grade (grade 1 29+/-37; grade 2 58+/-51; grade 3 84+/-132 GMU/mL, P<0.05). There was no relation between plasma IgG levels and NASH stage. CONCLUSIONS: Plasma IgG levels against endotoxin were found to be increased in biopsy-proven human NASH and increased with aggravated inflammation in NASH, suggesting a relationship between chronic endotoxin exposure and the severity of human NASH

Small intestinal alterations in severely obese hyperglycemic subjects

Context: Type 2 diabetes mellitus (DM2) is associated with small intestinal hyperplasia and hypertrophy in rodents. Moreover, the small intestine is increasingly acknowledged to play a role in the pathophysiology of DM2. Objective: The objective of the study was to investigate the relation between plasma markers of small intestinal function and chronic hyperglycemia in man. Design, Setting, and Participants: We conducted a cross-sectional observational study of 40 severely obese subjects with chronic hyperglycemia and 30 severely obese subjects without chronic hyperglycemia who were indicated for bariatric surgery. Main Outcome Measures: We assessed plasma levels of citrulline, representing small intestinal enterocyte mass, intestinal fatty acid binding protein (I-FABP), a marker of enterocyte loss, and glucagon-like peptide-2, an intestinotrophic factor, and related them to glycated hemoglobin (HbA1c) levels. Results: Plasma citrulline and I-FABP levels were both significantly elevated in subjects with chronic hyperglycemia (HbA1c > 6.0%) compared with subjects with a normal HbA1c (</= 6.0%) (citrulline, 35 +/- 2.1 muM vs. 26 +/- 1.4 muM, P = 0.001; I-FABP, 140 +/- 22 pg/ml vs. 69 +/- 14 pg/ml, P = 0.001). Moreover, plasma citrulline and I-FABP levels correlated with HbA1c levels (citrulline, rs = 0.30, P = 0.02; I-FABP, rs = 0.33, P = 0.005). The I-FABP to citrulline ratio was higher in subjects with an elevated HbA1c (4.0 vs. 3.1, P = 0.03). Plasma glucagon-like peptide-2 levels were not related to citrulline or I-FABP levels (rs = 0.06, P = 0.67; rs 0.08, P = 0.54, respectively). Conclusion: Chronically elevated glucose levels in obese individuals are associated with increased small intestinal enterocyte mass and increased enterocyte loss. These findings argue for the further exploration of the role of the intestine in the pathophysiology of DM2

Total parenteral nutrition induces a shift in the firmicutes to bacteroidetes ratio in association with paneth cell activation in rats.

The use of total parenteral nutrition (TPN) in the treatment of critically ill patients has been the subject of debate because it has been associated with disturbances in intestinal homeostasis. Important factors in maintaining the intestinal homeostasis are the intestinal microbiota and Paneth cells, which exist in a mutually amendable relationship. We hypothesized that the disturbed intestinal homeostasis in TPN-fed individuals results from an interplay between a shift in microbiota composition and alterations in Paneth cells. We studied the microbiota composition and expression of Paneth cell antimicrobial proteins in rats receiving TPN or a control diet for 3, 7, or 14 d. qPCR analysis of DNA extracts from small intestinal luminal contents of TPN-fed rats showed a shift in Firmicutes:Bacteroidetes ratio in favor of Bacteroidetes after 14 d (P < 0.05) compared with the control group. This finding coincided with greater staining intensity for lysozyme and significantly greater mRNA expression of Paneth cell antimicrobial proteins lysozyme (P < 0.05), rat alpha-defensin 5 (P < 0.01), and rat alpha-defensin 8 (P < 0.01). Finally, 14 d of TPN resulted in greater circulating ileal lipid-binding protein concentrations (P < 0.05) and greater leakage of horseradish peroxidase (P < 0.01), which is indicative of enterocyte damage and a breached intestinal barrier. Our findings show a shift in intestinal microbiota in TPN-fed rats that correlated with changes in Paneth cell lysozyme expression (r(s) = -0.75, P < 0.01). Further studies that include interventions with microbiota or nutrients that modulate them may yield information on the involvement of microbiota and Paneth cells in TPN-associated intestinal compromise