Endotoxin Induced Chorioamnionitis Prevents Intestinal Development during Gestation in Fetal Sheep

Chorioamnionitis is the most significant source of prenatal inflammation and preterm delivery. Prematurity and prenatal inflammation are associated with compromised postnatal developmental outcomes, of the intestinal immune defence, gut barrier function and the vascular system. We developed a sheep model to study how the antenatal development of the gut was affected by gestation and/or by endotoxin induced chorioamnionitis

The PPARγ Agonist Rosiglitazone Impairs Colonic Inflammation in Mice with Experimental Colitis

Various animal models showed that peroxisome proliferator-activated receptor (PPAR)γ agonists, when given as a gavage shortly preceding colitis induction, protect against inflammatory bowel disease (IBD). We have examined the effects of 16 days rosiglitazone treatment via the diet prior to dextran sodium sulphate (DSS)-induced colitis in mice. After 7 days DSS in the drinking water, rosiglitazone-fed mice had lost significantly more weight than control mice. Rosiglitazone-treated mice had more diarrhea, weight of colon and spleen were increased, and length of colon was decreased. Histology showed that rosiglitazone-treated mice had more severe colitis, mainly caused by more ulceration, crypt loss, and edema. Immunofluorescence showed a loss of tight junction structure Zonula Occludens protein 1 (ZO-1) in colons of rosiglitazone-treated mice as compared to control mice. Also, serum amyloid P component (SAP) concentrations in plasma were increased. However, concentrations of tumor necrosis factor (TNF)-α and interferon (IFN)-γ in colon homogenates, and TNF-α in spleen homogenates were significantly decreased, whereas interleukin (IL)-10 in spleen homogenates was increased. Other cytokines (IL-2, IL-4, IL-6, IL-12p70 and monocyte chemotactic protein (MCP)-1) and myeloperoxidase (MPO) concentrations showed no differences. In conclusion, 16 days pretreatment with rosiglitazone impaired DSS-induced colitis in mice

New Insight in Loss of Gut Barrier during Major Non-Abdominal Surgery

PG - e3954 AB - BACKGROUND: Gut barrier loss has been implicated as a critical event in the occurrence of postoperative complications. We aimed to study the development of gut barrier loss in patients undergoing major non-abdominal surgery. METHODOLOGY/PRINCIPAL FINDINGS: Twenty consecutive children undergoing spinal fusion surgery were included. This kind of surgery is characterized by long operation time, significant blood loss, prolonged systemic hypotension, without directly leading to compromise of the intestines by intestinal manipulation or use of extracorporeal circulation. Blood was collected preoperatively, every two hours during surgery and 2, 4, 15 and 24 hours postoperatively. Gut mucosal barrier was assessed by plasma markers for enterocyte damage (I-FABP, I-BABP) and urinary presence of tight junction protein claudin-3. Intestinal mucosal perfusion was measured by gastric tonometry (P(r)CO2, P(r-a)CO2-gap). Plasma concentration of I-FABP, I-BABP and urinary expression of claudin-3 increased rapidly and significantly after the onset of surgery in most children. Postoperatively, all markers decreased promptly towards baseline values together with normalisation of MAP. Plasma levels of I-FABP, I-BABP were significantly negatively correlated with MAP at (1/2) hour before blood sampling (-0.726 (p<0.001), -0.483 (P<0.001), respectively). Furthermore, circulating I-FABP correlated with gastric mucosal P(r)CO2, P(r-a)CO2-gap measured at the same time points (0.553 (p = 0.040), 0.585 (p = 0.028), respectively). CONCLUSIONS/SIGNIFICANCE: This study shows the development of gut barrier loss in children undergoing major non-abdominal surgery, which is related to preceding hypotension and mesenterial hypoperfusion. These data shed new light on the potential role of peroperative circulatory perturbation and intestinal barrier los

Non-invasive assessment of barrier integrity and function of the human gut

Over the past decades evidence has been accumulating that intestinal barrier integrity loss plays a key role in the development and perpetuation of a variety of disease states including inflammatory bowel disease and celiac disease, and is a key player in the onset of sepsis and multiple organ failure in situations of intestinal hypoperfusion, including trauma and major surgery. Insight into gut barrier integrity and function loss is important to improve our knowledge on disease etiology and pathophysiology and contributes to early detection and/or secondary prevention of disease. A variety of tests have been developed to assess intestinal epithelial cell damage, intestinal tight junction status and consequences of intestinal barrier integrity loss, i.e. increased intestinal permeability. This review discusses currently available methods for evaluating loss of human intestinal barrier integrity and function

Protection against early intestinal compromise by lipid-rich enteral nutrition through cholecystokinin receptors

Objective: Early gut wall integrity loss and local intestinal inflammation are associated with the development of inflammatory complications in surgical and trauma patients. Prevention of these intestinal events is a potential target for therapies aimed to control systemic inflammation. Previously, we demonstrated in a rodent shock model that lipid-rich enteral nutrition attenuated systemic inflammation and prevented organ damage through a cholecystokinin receptor-dependent vagal pathway. The influence of lipid-rich nutrition on very early intestinal compromise as seen after shock is investigated. Next, the involvement of cholecystokinin receptors on the nutritional modulation of immediate gut integrity loss and intestinal inflammation is studied. Design: Randomized controlled in vivo study. Setting: University research unit. Subjects: Male Sprague-Dawley rats. Interventions: Liquid lipid-rich nutrition or control low-lipid feeding was administered per gavage before hemorrhagic shock. Cholecystokinin receptor antagonists were used to investigate involvement of the vagal antiinflammatory pathway. Measurements and Main Results: Gut permeability to horseradish peroxidase increased as soon as 30 mins postshock and was prevented by lipid-rich nutrition compared with low-lipid (p <.01) and fasted controls (p <.001). Furthermore, lipid-rich nutrition reduced plasma levels of enterocyte damage marker ileal lipid binding protein at 60 mins (p <.05). Early gut barrier dysfunction correlated with rat mast cell protease plasma concentrations at 30 mins (r(s) = 0.67; p <.001) and intestinal myeloperoxidase levels at 60 mins (r(s) = 0.58; p <.05). Lipid-rich nutrition significantly reduced plasma rat mast cell protease (p <.01) and myeloperoxidase (p <.05) before systemic inflammation was detectable. Protective effects of lipid-rich nutrition were abrogated by cholecystokinin receptor antagonists (horseradish peroxidase; p <.05 and rat mast cell protease; p <.05). Conclusions: Lipid-rich enteral nutrition prevents early gut barrier loss, enterocyte damage, and local intestinal inflammation before systemic inflammation develops in a cholecystokinin receptor-dependent manner. This study identifies activation of the vagal antiinflammatory pathway with lipid-rich nutrition as a potential therapy in patients prone to develop a compromised gut. (Crit Care Med 2010; 38:1592-1597

A pilot study on potential new plasma markers for diagnosis of acute appendicitis

Background: Diagnosis of acute appendicitis (AA) remains a surgical dilemma, with negative appendectomy rates of 5% to 40% and perforation suggestive for late operative intervention in 5% to 30%. The aim of this study is to evaluate new plasma markers, representing early neutrophil activation, to improve diagnostic accuracy in patients suspected for AA. Materials and Methods: Fifty-one patients who underwent surgery for AA were included (male-female = 28:23), and blood was sampled. Plasma concentrations of 2 neutrophil proteins were measured: lactoferrin (LF) and calprotectin (CP). Controls consisted of 27 healthy volunteers. C-reactive protein (CRP) and white blood cell count (WBC) concentrations were measured for routine patient care. Results: Median plasma concentrations for LF and CP were significantly higher in 51 patients with proven AA (665 and 766 ng/mL, respectively) than in 27 healthy volunteers (198 and 239 ng/mL, respectively, P < .001). No clinically relevant correlation exists between the plasma levels of LF and CP and the conventional laboratory tests for CRP and WBC. Conclusions: Circulating LF and CP levels are significantly elevated in patients with appendicitis and are detectable in plasma using relatively simple and low-cost enzyme-linked immunosorbent assays. Furthermore, plasma levels of LF and CP give additional information to conventional markers WBC and CRP, making them potential new markers for AA diagnosis

Urine-based detection of intestinal tight junction loss

Tight junction breakdown, with loss of the important sealing protein claudin-3, is an early event in the development of intestinal damage. Therefore, noninvasive analysis of intestinal tight junction status could be helpful in early detection of intestinal injury. To investigate the usefulness of urinary claudin-3 as marker for intestinal tight junction loss. A rat hemorrhagic shock model and a human setting of known intestinal damage, that is, patients with relapsed inflammatory bowel disease (IBD), were used to investigate intestinal tight junction status by immunohistochemical staining and urinary claudin-3 levels by western blot. In rats claudin-3 urine levels increased rapidly after histologically proven intestinal tight junction loss, with significantly elevated levels at 90 minutes after shock compared with sham-operated animals [mean+/-SEM: 611+/-101 intensity (INT), n=6 vs. 232+/-30 INT, n=6; P <0.05]. Moreover, in colonic biopsies of patients with IBD relapse claudin-3 staining was reduced compared with biopsies of patients with IBD without signs of disease. Concomitantly, significantly increased claudin-3 urine levels were found in these patients (502+/-67 INT, n=10) compared with patients with IBD in remission (219+/-17 INT, n=10, P <0.001) and healthy volunteers (225+/-38 INT, n=10, P <0.001). Here we show for the first time in both an experimental and clinical setting a strong relation between intestinal tight junction loss and urinary claudin-3 levels. These findings suggest that measurement of urinary claudin-3 can be used as noninvasive marker for intestinal tight junction loss. This offers new opportunities for early diagnosis and follow-up of intestinal injur

Early Diagnosis of Intestinal Ischemia Using Urinary and Plasma Fatty Acid Binding Proteins

Objective: This study aims at improving diagnosis of intestinal ischemia, by measuring plasma and urinary fatty acid binding protein (FABP) levels. Methods: Fifty consecutive patients suspected of intestinal ischemia were included and blood and urine were sampled at time of suspicion. Plasma and urinary concentrations of intestinal FABP (I-FABP), liver FABP (L-FABP) and ileal bile acid binding protein (I-BABP) were measured using enzyme linked immunosorbent assays. Results: Twenty-two patients suspected of intestinal ischemia were diagnosed with intestinal ischemia, 24 patients were diagnosed with other diseases, and 4 patients were excluded from further analysis fulfilling exclusion criteria. Median plasma concentrations of I-FABP and L-FABP and urinary concentrations of all 3 markers were significantly higher in patients with proven intestinal ischemia than in patients suspected of intestinal ischemia with other final diagnoses (plasma I-FABP; 653 pg/mL vs. 109 pg/mL, P = 0.02, plasma L-FABP; 117 ng/mL vs. 25 ng/mL, P = 0.006, urine I-FABP; 3377 pg/mL vs. 115 pg/mL, P = 0.001, urine L-FABP; 1,199 ng/mL vs. 37 ng/mL, P = 0.004, urine I-BABP; 48.6 ng/mL vs. 0.6 ng/mL, P = 0.002). Positive and negative likelihood ratios significantly increased positive posttest probability and decreased negative posttest probability on intestinal ischemia. In patients with intestinal ischemia a trend to higher plasma I-BABP levels was observed when the ileum was involved (18.4 ng/mL vs. 2.9 ng/mL, P = 0.05). Conclusion: Plasma and especially urinary I-FABP and L-FABP levels and urinary I-BABP levels can improve early diagnosis of intestinal ischemia. Furthermore, plasma I-BABP levels can help in localizing ileal ischemia

Chorioamnionitis-induced fetal gut injury is mediated by direct gut exposure of inflammatory mediators or by lung inflammation

Intra-amniotic exposure to proinflammatory agonists causes chorioamnionitis and fetal gut inflammation. Fetal gut inflammation is associated with mucosal injury and impaired gut development. We tested whether this detrimental inflammatory response of the fetal gut results from a direct local (gut derived) or an indirect inflammatory response mediated by the chorioamnion/skin or lung, since these organs are also in direct contact with the amniotic fluid. The gastrointestinal tract was isolated from the respiratory tract and the amnion/skin epithelia by fetal surgery in time-mated ewes. Lipopolysaccharide (LPS) or saline (controls) was selectively infused in the gastrointestinal tract, trachea, or amniotic compartment at 2 or 6 days before preterm delivery at 124 days gestation (term 150 days). Gastrointestinal and intratracheal LPS exposure caused distinct inflammatory responses in the fetal gut. Inflammatory responses could be distinguished by the influx of leukocytes (MPO(+), CD3(+), and FoxP3(+) cells), tumor necrosis factor-α, and interferon-γ expression and differential upregulation of mRNA levels for Toll-like receptor 1, 2, 4, and 6. Fetal gut inflammation after direct intestinal LPS exposure resulted in severe loss of the tight junctional protein zonula occludens protein 1 (ZO-1) and increased mitosis of intestinal epithelial cells. Inflammation of the fetal gut after selective LPS instillation in the lungs caused only mild disruption of ZO-1, loss in epithelial cell integrity, and impaired epithelial differentiation. LPS exposure of the amnion/skin epithelia did not result in gut inflammation or morphological, structural, and functional changes. Our results indicate that the detrimental consequences of chorioamnionitis on fetal gut development are the combined result of local gut and lung-mediated inflammatory responses