Fecal Blood Loss Research Articles

Faecal occult blood loss accurately predicts future detection of colorectal cancer. A prognostic model

ObjectivesTo examine the prognostic potential of repeated faecal haemoglobin (F-Hb) concentration measurements in faecal immunochemical test (FIT)-based screening for colorectal cancer (CRC).DesignPrognostic model.SettingDutch biennial FIT-based screening programme during 2014–2018.Participants265 881...

Predictive value of alarm symptoms in Rome IV irritable bowel syndrome: A multicenter cross-sectional study.

BACKGROUNDIrritable bowel syndrome (IBS) is a common functional bowel disease that shares features with many organic diseases and cannot be accurately diagnosed by symptom-based criteria. Alarm symptoms have long been applied in the clinical diagnosis of IBS. However, no study has explored the predictive value of alarm symptoms in suspected IBS patients based on the latest Rome IV criteria.AIMTo investigate the predictive value of alarm symptoms in suspected IBS patients based on the Rome IV criteria.METHODSIn this multicenter cross-sectional study, we collected data from 730 suspected IBS patients evaluated at 3 tertiary care centers from August 2018 to August 2019. Patients with IBS-like symptoms who completed colonoscopy during the study period were initially identified by investigators through medical records. Eligible patients completed questionnaires, underwent laboratory tests, and were assigned to the IBS or organic disease group according to colonoscopy findings and pathology results (if a biopsy was taken). Independent risk factors for organic disease were explored by logistic regression analysis, and the positive predictive value (PPV) and missed diagnosis rate were calculated.RESULTSThe incidence of alarm symptoms in suspected IBS patients was 75.34%. Anemia [odds ratio (OR) = 2.825, 95% confidence interval (CI): 1.273-6.267, P = 0.011], fecal occult blood [OR = 1.940 (95%CI: 1.041-3.613), P = 0.037], unintended weight loss (P = 0.009), female sex [OR = 0.560 (95%CI: 0.330-0.949), P = 0.031] and marital status (P = 0.030) were independently correlated with organic disease. The prevalence of organic disease was 10.41% in suspected IBS patients. The PPV of alarm symptoms for organic disease was highest for anemia (22.92%), fecal occult blood (19.35%) and unintended weight loss (16.48%), and it was 100% when these three factors were combined. The PPV and missed diagnosis rate for diagnosing IBS were 91.67% and 74.77% when all alarm symptoms were combined with Rome IV and 92.09% and 34.10% when only fecal occult blood, unintended weight loss and anemia were combined with Rome IV, respectively.CONCLUSIONAnemia, fecal occult blood and unintended weight loss have high predictive value for organic disease in suspected IBS patients and can help identify patients requiring further examination but are not recommended as exclusion criteria for IBS.

6-(methylsulfinyl)hexyl isothiocyanate (6-MITC) from Wasabia japonica alleviates inflammatory bowel disease (IBD) by potential inhibition of glycogen synthase kinase 3 beta (GSK-3β).

Inflammatory bowel disease (IBD) describes a set of disorders involving alterations to gastrointestinal physiology and mucosal immunity. Unravelling its complex pathophysiology is important since many IBD patients are refractory to or suffer adverse side effects from current treatments. Isothiocyanates (ITCs), such as 6-(methylsulfinyl)hexyl ITC (6-MITC) in Wasabia japonica, have potential anti-inflammatory activity. We aimed to elucidate the pathways through which 6-MITC alleviates inflammation by examining its role in the nuclear factor-kappa B (NF-κB) pathway through inhibition of glycogen synthase kinase 3 beta (GSK-3β) using a chemically induced murine model of IBD, cell-based and in silico techniques. The effects of 6-MITC and two NF-κB inhibitors, sulfasalazine (SS), pyrrolidine dithiolcarbamate (PDTC) were investigated on a dextran sulfate sodium (DSS)-induced murine mouse model of acute and chronic colitis using macroscopic measurements and pro-inflammatory markers. The effect of 6-MITC on NF-κB induction was assessed using a murine macrophage cell line. Complexes of GSK-3β-6-MITC and GSK-3β-ATP were generated in silico to elucidate the mechanism of 6-MITC's direct inhibition of GSK-3β. Changes in pro-inflammatory markers, inducible nitric oxide synthase (iNOS) (increased) and interleukin-6 (IL-6) (decreased) demonstrated that iNOS regulation occurred at the translational level. Intraperitoneal (ip) injection of 6-MITC to the colitis-induced mice ameliorated weight loss whereas oral administration had negligible effect. Fecal blood and colon weight/length ratio parameters improved on treatment with 6-MITC and the other NF-κB inhibitors. Levels of NF-κB decreased upon addition of 6-MITC invitro while structural studies showed 6-MITC acts competitively to inhibit GSK-3β at the ATP binding site. In this study we demonstrated that 6-MITC inhibits NF-κB signaling via GSK-3β inhibition ameliorating fecal blood, colonic alterations and DSS-induced weight loss indirectly indicating reduced intestinal stress. Taken together these results suggest a role for 6-MITC in the treatment of IBD acting to alleviate inflammation through the GSK-3β/NF-κB pathway. Furthermore, the GSK-3β-6-MITC model can be utilized as a basis for development of novel therapeutics targeting GSK-3β for use in other disorders including cancer.

Screening for fecal occult blood loss in severely malnourished children

Introduction: PEM is the most important and basic hurdle in the triple-M complex of malnutrition,morbidity, and mortality. Very high mortality has been reported in severe PEM. PEM is found toaccount for about 4 million deaths in children. The study aimed to perform a fecal occult blood testin patients in the age group of six months to five years and also to identify the conditions associatedwith fecal occult blood loss in pem patients. Materials and Methods: A total of 100 indoor patientsof PEM admitted in our pediatric ward were taken as subjects in this study. According to WHO andIAP classification of PEM, severe malnutrition (marasmus, kwashiorkor, and marasmic kwashiorkor)were taken as study group; and mild grades of PEM (grade I and grade II) were taken as a controlgroup. Results: In severe PEM, marasmus (83%) was more common followed by kwashiorkor(14%) and marasmic kwashiorkor (3%); however in mild grades of PEM, grade I PEM was found in58% and grade II PEM was found in 42%. In severe PEM, pallor (64%), hair changes (38%), andtachypnoea(31%) were major clinical signs; while tachypnoea(36%), dehydration (26%), and pallor(20%} were major clinical signs in patients with mild grades of PEM. Conclusion: A positive fecaloccult blood test (FOBT) is strongly associated with moderate to severe anemia in severe PEMpatients. So all patients having a positive FOBT should have a hemogram profile done and thenappropriately treated for anemia.

Fecal blood loss: A quantitative method of evaluating hemostasis in patients with thrombocytopenia.

The purpose of our studies was to determine if fecal blood loss can provide a quantitative measure of bleeding at platelet counts of 20 000/μL or less in patients with hypoproliferative thrombocytopenia and to document the effects of different prophylactic platelet transfusion triggers on fecal blood loss. Patients had an aliquot of their autologous red blood cells (RBCs) labeled with 51 Cr. Following reinjection of their radiolabeled RBCs, all feces and a daily blood sample were collected to determine fecal blood loss per day. Three different studies were performed in patients with thrombocytopenia: The first was in patients with thrombocytopenia with aplastic anemia who were not receiving platelet transfusions, and the other two trials involved thrombocytopenic patients with cancer who were receiving prophylactic platelet transfusions at platelet transfusion triggers of 5000/μL, 10 000/μL, or 20 000/μL. In patients with thrombocytopenia not receiving platelet transfusions, fecal blood loss does not increase substantially until platelet counts are 5000/μL or less. When platelet transfusions are given prophylactically to patients with cancer with chemotherapy-induced thrombocytopenia at platelet counts of 5000/μL or less, fecal blood loss and red cell transfusion requirements are the same as those for patients transfused prophylactically at higher transfusion triggers of 10 000 platelets/μL or 20 000 platelets/μL. However, the total number of platelet transfusions needed increases significantly, and the duration of the patient's thrombocytopenia tends to be longer at the higher platelet transfusion thresholds. A prophylactic platelet transfusion threshold of 5000/μL or greater is sufficient to maintain hemostasis in patients with thrombocytopenia.

Silent bleeding in children and adolescents with immune thrombocytopenia: relation to laboratory parameters and health related quality of life.

Occult hemorrhage can occur in any internal organ in ITP patients. Four sites of occult hemorrhage require attention including microscopic hematuria, fecal occult blood loss, retinal hemorrhage, and silent intracranial hemorrhage. The aim of this study was to investigate the frequency of subclinical bleeding in children with ITP and its relation to clinical and laboratory disease parameters including bleeding score and health related quality of life. This cross-sectional study included 40 ITP patients recruited from the Pediatric Hematology/Oncology unit, Children's Hospital, Ain Shams University, Cairo, Egypt. Inclusion criteria were patients with ITP (acute, persistent or chronic) having platelet count of 20,000/cmm or less at diagnosis/relapse, patients with overt bleeding and patients with secondary ITP were excluded. Occult blood in stools and urine analysis, fundus examination, and non-contrast brain MRI for microbleeds were done. Out of the forty included patients, 24 had chronic, 11 had acute and 5 had persistent ITP. Eleven patients had occult bleeds. Two patients had occult blood in stools, five had microscopic hematuria, one had retinal bleeds and three patients had brain microbleeds. Their mean age was 10.23 ± 4.18years and their mean initial bleeding score was 2.55 ± 0.82. Nine patients with occult bleeding were chronic, one persistent and one acute ITP patients. There were no significant differences between patients with occult bleeding and those without as regards the initial bleeding score, platelet counts and hemoglobin level, as well as the mean platelet counts and mean hemoglobin level over the disease duration (p > 0.5). The scoring of the parent's life, Child and parents' quality of life was low in 3 out of 11 patients with occult bleeding. There was no significant difference between patients with occult bleeding and those without as regards the ITP child and parents' quality of life items (p = 0.850 and 0.511 respectively). Our results suggest that subclinical bleeding is a potential risk in children with ITP, more commonly chronic ITP patients. We could not demonstrate a significant relation of occult bleeding to the laboratory findings, bleeding score, and the ITP health quality of life; nevertheless, the significance of the routine assessment of occult bleeding in ITP and the identification of high-risk patients require additional studies.

Performance of behavioral assays: the Rat Grimace Scale, burrowing activity and a composite behavior score to identify visceral pain in an acute and chronic colitis model.

The Rat Grimace Scale (RGS), a facial expression scale, quantifies the affective component of pain in rats. The RGS was developed to identify acute and inflammatory pain, and applicability in acute and chronic visceral pain is unknown. The dextran sulfate sodium (DSS) colitis model is commonly used in rats, but pain is rarely assessed, instead, disease progression is monitored with the Disease Activity Index (DAI; assessing fecal blood, stool consistency, and weight loss). The aim of this study was to assess whether the RGS and 2 additional behavioral tools (composite behavior score [CBS] and burrowing) could identify pain in an acute and chronic DSS colitis model. Male and female Sprague-Dawley rats were block randomized to (1) acute colitis (4 days DSS in drinking water); (2) chronic colitis (4 days DSS, 7 days water, and 3 days DSS); or (3) control (14 days water). Disease Activity Index, RGS, CBS, and burrowing assessments were performed daily. Rat Grimace Scale scores increased as DAI scores increased during both acute and chronic phases. Burrowing only decreased during the acute phase. By contrast, CBS scores did not increase significantly during either colitis phase. These data show that the RGS and burrowing did not decrease in a sustained manner during chronic phase visceral pain, and that variables assessed in the DAI are indicative of pain. This suggests that the RGS can be applied to a wider range of pain types and chronicity than originally suggested. These findings increase the application of the RGS as a pain scale and welfare improvement tool.

Anti-inflammatory effects of the selective phosphodiesterase 3 inhibitor, cilostazol, and antioxidants, enzymatically-modified isoquercitrin and α-lipoic acid, reduce dextran sulphate sodium-induced colorectal mucosal injury in mice

Developing effective treatments and preventing inflammatory bowel disease (IBD) are urgent challenges in improving patients’ health. It has been suggested that platelet activation and reactive oxidative species generation are involved in the pathogenesis of IBD. We examined the inhibitory effects of a selective phosphodiesterase-3 inhibitor, cilostazol (CZ), and two antioxidants, enzymatically modified isoquercitrin (EMIQ) and α-lipoic acid (ALA), against dextran sulphate sodium (DSS)-induced colitis. BALB/c mice were treated with 0.3% CZ, 1.5% EMIQ, and 0.2% ALA in their feed. Colitis was induced by administering 5% DSS in drinking water for 8days. The inhibitory effects of these substances were evaluated by measuring relevant clinical symptoms (faecal blood, diarrhoea, and body weight loss), colon length, plasma cytokine and chemokine levels, whole genome gene expression, and histopathology. Diarrhoea was suppressed by each treatment, while CZ prevented shortening of the colon length. All treatment groups exhibited decreased plasma levels of interleukin (IL)-6 and tumour necrosis factor (TNF)-α compared with the DSS group. Microarray analysis showed that cell adhesion, cytoskeleton regulation, cell proliferation, and apoptosis, which might be related to inflammatory cell infiltration and mucosal healing, were affected in all the groups. DSS-induced mucosal injuries such as mucosal loss, submucosal oedema, and inflammatory cell infiltration in the distal colon were prevented by CZ or antioxidant treatment. These results suggest that anti-inflammatory effects of these agents reduced DSS-induced mucosal injuries in mice and, therefore, may provide therapeutic benefits in IBD.

Dietary Composition Influences Incidence of Helicobacter pylori-Induced Iron Deficiency Anemia and Gastric Ulceration

Epidemiologic studies have provided conflicting data regarding an association between Helicobacter pylori infection and iron deficiency anemia (IDA) in humans. Here, a Mongolian gerbil model was used to investigate a potential role of H. pylori infection, as well as a possible role of diet, in H. pylori-associated IDA. Mongolian gerbils (either H. pylori infected or uninfected) received a normal diet or one of three diets associated with increased H. pylori virulence: high-salt, low-iron, or a combination of a high-salt and low-iron diet. In an analysis of all infected animals compared to uninfected animals (independent of diet), H. pylori-infected gerbils had significantly lower hemoglobin values than their uninfected counterparts at 16 weeks postinfection (P < 0.0001). The mean corpuscular volume (MCV) and serum ferritin values were significantly lower in H. pylori-infected gerbils than in uninfected gerbils, consistent with IDA. Leukocytosis and thrombocytosis were also detected in infected gerbils, indicating the presence of a systemic inflammatory response. In comparison to uninfected gerbils, H. pylori-infected gerbils had a higher gastric pH, a higher incidence of gastric ulcers, and a higher incidence of fecal occult blood loss. Anemia was associated with the presence of gastric ulceration but not gastric cancer. Infected gerbils consuming diets with a high salt content developed gastric ulcers significantly more frequently than gerbils consuming a normal-salt diet, and the lowest hemoglobin levels were in infected gerbils consuming a high-salt/low-iron diet. These data indicate that H. pylori infection can cause IDA and that the composition of the diet influences the incidence and severity of H. pylori-induced IDA.

Orally Administered Enoxaparin Ameliorates Acute Colitis by Reducing Macrophage-Associated Inflammatory Responses.

Inflammatory bowel diseases, such as ulcerative colitis, cause significant morbidity and decreased quality of life. The currently available treatments are not effective in all patients, can be expensive and have potential to cause severe side effects. This prompts the need for new treatment modalities. Enoxaparin, a widely used antithrombotic agent, is reported to possess anti-inflammatory properties and therefore we evaluated its therapeutic potential in a mouse model of colitis. Acute colitis was induced in male C57BL/6 mice by administration of dextran sulfate sodium (DSS). Mice were treated once daily with enoxaparin via oral or intraperitoneal administration and monitored for colitis activities. On termination (day 8), colons were collected for macroscopic evaluation and cytokine measurement, and processed for histology and immunohistochemistry. Oral but not intraperitoneal administration of enoxaparin significantly ameliorated DSS-induced colitis. Oral enoxaparin-treated mice retained their body weight and displayed less diarrhea and fecal blood loss compared to the untreated colitis group. Colon weight in enoxaparin-treated mice was significantly lower, indicating reduced inflammation and edema. Histological examination of untreated colitis mice showed a massive loss of crypt architecture and goblet cells, infiltration of immune cells and the presence of edema, while all aspects of this pathology were alleviated by oral enoxaparin. Reduced number of macrophages in the colon of oral enoxaparin-treated mice was accompanied by decreased levels of pro-inflammatory cytokines. Oral enoxaparin significantly reduces the inflammatory pathology associated with DSS-induced colitis in mice and could therefore represent a novel therapeutic option for the management of ulcerative colitis.

Fucoidan Extracts Ameliorate Acute Colitis.

Inflammatory bowel diseases (IBD), such as ulcerative colitis and Crohn’s disease, are an important cause of morbidity and impact significantly on quality of life. Overall, current treatments do not sustain a long-term clinical remission and are associated with adverse effects, which highlight the need for new treatment options. Fucoidans are complex sulphated, fucose-rich polysaccharides, found in edible brown algae and are described as having multiple bioactivities including potent anti-inflammatory effects. Therefore, the therapeutic potential of two different fucoidan preparations, fucoidan-polyphenol complex (Maritech Synergy) and depyrogenated fucoidan (DPF) was evaluated in the dextran sulphate sodium (DSS) mouse model of acute colitis. Mice were treated once daily over 7 days with fucoidans via oral (Synergy or DPF) or intraperitoneal administration (DPF). Signs and severity of colitis were monitored daily before colons and spleens were collected for macroscopic evaluation, cytokine measurements and histology. Orally administered Synergy and DPF, but not intraperitoneal DPF treatment, significantly ameliorated symptoms of colitis based on retention of body weight, as well as reduced diarrhoea and faecal blood loss, compared to the untreated colitis group. Colon and spleen weight in mice treated with oral fucoidan was also significantly lower, indicating reduced inflammation and oedema. Histological examination of untreated colitis mice confirmed a massive loss of crypt architecture and goblet cells, infiltration of immune cells and oedema, while all aspects of this pathology were alleviated by oral fucoidan. Importantly, in this model, the macroscopic changes induced by oral fucoidan correlated significantly with substantially decreased production of at least 15 pro-inflammatory cytokines by the colon tissue. Overall, oral fucoidan preparations significantly reduce the inflammatory pathology associated with DSS-induced colitis and could therefore represent a novel nutraceutical option for the management of IBD.

DSS-induced acute colitis in C57BL/6 mice is mitigated by sulforaphane pre-treatment

The Brassica-derived isothiocyanate sulforaphane (SFN) is known to induce factor erythroid 2-related factor 2 (Nrf2), a transcription factor centrally involved in chemoprevention. Furthermore, SFN exhibits anti-inflammatory properties in vitro and in vivo. However, little is known regarding the anti-inflammatory properties of SFN in severe inflammatory phenotypes. In the present study, we tested if pre-treatment with SFN protects mice from dextran sodium sulphate (DSS)-induced colitis.C57BL/6 mice received either phosphate-buffered saline (control) or 25 mg/kg body weight (BW) SFN per os for 7 days. Subsequently, acute colitis was induced by administering 4% DSS via drinking water for 5 days and BWs, stool consistency and faecal blood loss were recorded. Following endoscopic colonoscopy, mice were sacrificed, the organs excised and spleen weights and colon lengths measured. For histopathological analysis, distal colon samples were fixed in 4% para-formaldehyde, sectioned and stained with hematoxylin/eosin. Inflammatory biomarkers were also measured in distal colon.Treatment with SFN prior to colitis induction significantly minimised both BW loss and the disease activity index compared to control mice. Furthermore, colon lengths in SFN pre-treated mice were significantly longer than in control mice. Both macroscopic and microscopic analysis of the colon revealed attenuated inflammation in SFN pre-treated animals. mRNA analysis of distal colon samples confirmed reduced expression of inflammatory markers and increased expression of Nrf2-dependent genes in SFN pre-treated mice.Our results indicate that pre-treating mice with SFN confers protection from DSS-induced colitis. These protective effects were corroborated macroscopically, microscopically and at the molecular level.

IL-36g Promotes Intestinal Inflammation Via Intestinal Macrophage/DC Activation

The two most common forms of inflammatory bowel disease (IBD), Crohn's disease and ulcerative colitis, affect approximately 1.4 million people in the United States. Uncontrolled APCs reactivity toward commensal bacteria and the consequent pro-inflammatory cytokine production is implicated in disease pathogenesis. Neutralization of TNF is currently one of the most effective biological therapies for Crohn's patients, however, there remains a pressing need for the development of novel therapeutics targeting pro-inflammatory cytokines. Several members of the IL-1 family of cytokines, including IL-1a, IL-1b, IL-18 and IL-33 are associated with the pathophysiology of IBD. Since we have identified a member of the IL-1 family of cytokines, termed IL-36g, in a genetic screen for factors selectively expressed by inflammatory colonic lamina propria (cLP) macrophages, in this work we focus on defining the pathogenic role for IL-36g during intestinal inflammation. C57BL/6 mice were fed for 5 days with 3% DSS dissolved in drinking water, and IL-36Ra was injected intraperitoneally on days -1, 1 and 3. Animals were assessed daily for stool consistency, fecal blood, and weight loss. cLP cells were isolated by magnetic positive selection or cell sorting. Cell surface staining and intracellular cytokine detection was performed using labeled antibodies for CD45, CD103, CD11c, MHC-II, CD11b, F4/80, Ly6C, Cx3cr1-FITC, live/dead staining, CD4, TCRb, CD45, IL-17A, IFNg, and FoxP3. qPCR on total RNA from macrophages was performed using SYBR Green. Treg induction was performed by co-culture of macrophages, OT-II CD4+ T cells and OVA for 3 days. Our results demonstrated that IL-36g is highly induced in the inflamed colonic tissue of mice during acute and chronic intestinal inflammation with one of the major cell types expressing IL-36g in the inflamed colonic mucosa being inflammatory Ly6C+CX3CR1(lo) macrophages. This specific expression prompted us to investigate the modulation of the function of resident inflammatory macrophages, and we observed that inflammatory cLP macrophages isolated from DSStreated mice failed to promote Foxp3 induction in responding CD4+ T cells when compared to control macrophages. The addition of IL-36g to co-cultures of T cells and cLP macrophages isolated from healthy mouse colon confirmed this specific inhibition of FoxP3 cell differentiation in the presence of IL-36g. Together, these data suggest that one important biological function of IL-36g is to inhibit Foxp3 Treg cell differentiation. We next examined the role of IL-36g in vivo during DSSinduced colitis by administration of the IL-36 receptor antagonist (IL-36Ra) on days -1, 1, and 3 of the DSS regimen, which resulted in a significant reduction in the overall disease when compared to mice that did not receive IL-36Ra. Since IL-36Ra blocks the function of IL-36R, which can bind IL-36a, IL-36b, and IL-36g, we conclude from these studies that at least one of these IL-36R ligands is important in the pathogenesis of intestinal inflammation. Collectively, our data demonstrate an important role for the macrophage-derived inflammatory cytokine IL-36g and the IL-36g/IL-36R axis during the pathogenesis of intestinal inflammation. The present work will aid in understanding appropriate targets for immunotherapy. This work was supported by CCFA (RFA, CDA) and NIH (AA017870 and AI083554) awards.

Rethinking Iron Regulation and Assessment in Iron Deficiency, Anemia of Chronic Disease, and Obesity: Introducing Hepcidin

Adequate iron availability is essential to human development and overall health. Iron is a key component of oxygen-carrying proteins, has a pivotal role in cellular metabolism, and is essential to cell growth and differentiation. Inadequate dietary iron intake, chronic and acute inflammatory conditions, and obesity are each associated with alterations in iron homeostasis. Tight regulation of iron is necessary because iron is highly toxic and human beings can only excrete small amounts through sweat, skin and enterocyte sloughing, and fecal and menstrual blood loss. Hepcidin, a small peptide hormone produced mainly by the liver, acts as the key regulator of systemic iron homeostasis. Hepcidin controls movement of iron into plasma by regulating the activity of the sole known iron exporter ferroportin-1. Downregulation of the ferroportin-1 exporter results in sequestration of iron within intestinal enterocytes, hepatocytes, and iron-storing macrophages reducing iron bioavailability. Hepcidin expression is increased by higher body iron levels and inflammation and decreased by anemia and hypoxia. Importantly, existing data illustrate that hepcidin may play a significant role in the development of several iron-related disorders, including the anemia of chronic disease and the iron dysregulation observed in obesity. Therefore, the purpose of this article is to discuss iron regulation, with specific emphasis on systemic regulation by hepcidin, and examine the role of hepcidin within several disease states, including iron deficiency, anemia of chronic disease, and obesity. The relationship between obesity and iron depletion and the clinical assessment of iron status will also be reviewed.

Macrophages and liposomes in inflammatory disease: Friends or foes?

Liposome-encapsulated corticosteroids have shown to exert strong beneficial effects in inflammatory diseases, such as arthritis and cancer. To extend the clinical applicability of these potent nanomedicines, the therapeutic effect of dexamethasone phosphate loaded long-circulating liposomes (LCL-DXP) was evaluated in animal models of multiple sclerosis (MS) and Crohn's disease (CD). In mice with experimental autoimmune encephalitis (EAE), a model for MS, treatment with LCL-DXP, but not free DXP, resulted in a decrease in disease activity when compared to PBS treated mice. In contrast, in mice with chronic DSS-induced colitis, a model for CD, treatment with LCL-DXP did not induce an improvement, but in fact worsened the fecal blood loss after treatment, indicating an aggravation of the disease. It is hypothesized that modulation of macrophage polarization towards a M2 phenotype underlies the efficacy of corticosteroid-based drug delivery systems, which is supported by the presented data. On the one hand, M1 polarized macrophages are part of the pathogenesis of MS; the modulation to M2-polarization by LCL-DXP is therefore beneficial. On the other hand, M1-polarized intestinal macrophages fulfill a protective and inflammation-suppressing role in intestinal homeostasis; changing their phenotype to M2 causes reduced protection to invading microorganisms, leading to a more severe intestinal inflammation. These findings therefore indicate that the interplay between the specific phenotype of macrophages and the specific inflammatory context of the inflammatory disease in question may be an important determining factor in the therapeutic applicability of liposomal corticosteroids in inflammatory disease.

Dietary cheese whey protein protects rats against mild dextran sulfate sodium–induced colitis: Role of mucin and microbiota

Data from the literature suggest that the availability of the amino acids threonine, cysteine, or both, is limiting for mucin synthesis under conditions of chronic inflammatory bowel disease. Unlike casein, cheese whey protein is rich in these amino acids. The protective effect of cheese whey protein was examined using dextran sulfate sodium (DSS)-induced inflammation of the large intestine in rats that were fed a diet containing casein, cheese whey protein, or casein supplemented with threonine and cysteine. The clinical markers diarrhea and fecal blood were determined using biochemical assays, and gene expression of inflammation markers was used to quantify inflammation. The effect of dairy protein on mucin production was determined by gene expression of rat mucin 2 (MUC2) and by quantifying fecal mucin excretion. Fecal lactobacilli and bifidobacteria were determined using quantitative PCR. Dietary cheese whey protein reduced DSS-induced gene expression of the inflammation markers interleukin 1β, calprotectin, and inducible nitric oxide synthase, and diminished the clinical symptoms diarrhea and fecal blood loss. Moreover, cheese whey protein increased fecal mucin secretion without affecting gene expression of MUC2, suggesting enhanced mucin synthesis. In addition, cheese whey protein increased fecal lactobacilli and bifidobacteria counts. Supplementation of threonine and cysteine showed comparable effects. In conclusion, cheese whey protein protected rats against DSS-induced gut inflammation. This can most likely be explained by its threonine and cysteine content. Protection can be the result of both the stimulation of intestinal mucin synthesis and modification of microflora composition.

Antithrombotic effects of targeting αIIbβ3 signaling in platelets

AbstractαIIbβ3 interaction with fibrinogen promotes Src-dependent platelet spreading in vitro. To determine the consequences of this outside-in signaling pathway in vivo, a “β3(Δ760-762)” knockin mouse was generated that lacked the 3 C-terminal β3 residues (arginine-glycine-threonine [RGT]) necessary for αIIbβ3 interaction with c-Src, but retained β3 residues necessary for talin-dependent fibrinogen binding. β3(Δ760-762) mice were compared with wild-type β3+/+ littermates, β3+/− heterozygotes, and knockin mice where β3 RGT was replaced by β1 C-terminal cysteine-glycine-lysine (EGK) to potentially enable signaling by Src kinases other than c-Src. Whereas β3+/+, β3+/− and β3/β1(EGK) platelets spread and underwent tyrosine phosphorylation normally on fibrinogen, β3(Δ760-762) platelets spread poorly and exhibited reduced tyrosine phosphorylation of c-Src substrates, including β3 (Tyr747). Unlike control mice, β3(Δ760-762) mice were protected from carotid artery thrombosis after vessel injury with FeCl3. Some β3(Δ760-762) mice exhibited prolonged tail bleeding times; however, none demonstrated spontaneous bleeding, excess bleeding after surgery, fecal blood loss, or anemia. Fibrinogen binding to β3(Δ760-762) platelets was normal in response to saturating concentrations of protease-activated receptor 4 or glycoprotein VI agonists, but responses to adenosine diphosphate were impaired. Thus, deletion of β3 RGT disrupts c-Src–mediated αIIbβ3 signaling and confers protection from arterial thrombosis. Consequently, targeting αIIbβ3 signaling may represent a feasible antithrombotic strategy.

Anti-Thrombotic Effects of Targeting Outside-in αIIbβ3 Signaling in Platelets

Platelet activation by agonists stimulates high affinity binding of adhesive ligands, such as fibrinogen, to integrin αIIbβ3. In turn, ligand binding initiates Src kinase-dependent outside-in signaling, platelet spreading on sub-endothelial matrices, and platelet aggregation. Short-term integrin blockade by parenteral αIIbβ3 antagonists is effectively anti-thrombotic in certain clinical situations, but long-term blockade by oral αIIbβ3 antagonists has been problematic. As an alternative approach, we evaluated the feasibility of disrupting outside-in αIIbβ3 signaling in vivo. A “β3(Δ760-762)” knock-in mouse was generated that lacked the three C-terminal β3 amino acid residues (RGT) necessary for αIIbβ3-dependent c-Src signaling, but retained β3 residues necessary for agonist- and talin-dependent fibrinogen binding. β3(Δ760-762) mice were compared with wild-type β3+/+ littermates, β3+/− heterozygotes, and “β3/β1(EGK)” knock-in mice where β3 RGT was replaced by three C-terminal residues in β1 (EGK) to potentially enable outside-in integrin signaling by certain Src kinases other than c-Src. Whereas β3+/+, β3+/− and β3/β1(EGK) platelets spread and underwent tyrosine phosphorylation normally on fibrinogen, β3(Δ760-762) platelets spread poorly and exhibited reduced tyrosine phosphorylation of c-Src substrates, including the β3 cytoplasmic domain itself (Tyr-747). Furthermore, unlike the three groups of control mice, all of the β3(Δ760-762) mice tested were protected from carotid artery occlusive thrombosis following vessel injury with FeCl3. The median tail bleeding time for the β3(Δ760-762) mice was approximately two-fold longer than that of the control mice. However, β3(Δ760-762) mice did not exhibit spontaneous bleeding, excess bleeding after surgical exposure of the carotid artery, fecal blood loss or anemia. Fibrinogen binding to β3(Δ760-762) platelets was normal in response to saturating concentrations of agonists to the PAR4 thrombin receptor or the GP VI collagen receptor; however, responses to ADP were impaired. These studies establish that deletion of β3 RGT disrupts outside-in αIIbβ3 signaling and confers protection from arterial thrombosis in vivo. Currently available anti-platelet drugs either inhibit agonist-induced activation of αIIbβ3 or block fibrinogen binding to the integrin. The studies reported here suggest that targeting outside-in αIIbβ3 signaling may represent an alternative anti-thrombotic strategy.

Les étiologies des anémies ferriprives dans le service de médecine interne du centre hospitalier universitaire Yalgado-Ouédraogo de Ouagadougou

This retrospective study in the internal medicine department of the national teaching hospital of Ouagadougou was conducted to identify the main causes of iron-deficiency anaemia. Among the 65 subjects meeting the inclusion and exclusion criteria, mean haemoglobin was 7.5 g/dl, with mean serum ferritin 8.9 microg/l among women and 15.5 microg/l among men. The most common cause was chronic blood loss, and hookworm was a major cause in 19.6% of cases. These results suggest the need for preventive measures against iron deficiency and for reinforcement of the fight against diseases producing fecal blood loss.

Intestinal Blood Loss as an Aggravating Factor of Iron Deficiency in Infants Aged 9 to 12 Months Fed Whole Cow's Milk

To verify the occurrence of occult intestinal blood loss and iron deficiency in infants aged 9 to 12 months. A consecutive sample of 98 infants of the Pediatric Public Health Primary Care Unit in the town of Arapongas, Parana State, Brazil was involved in this cross-sectional study. Dietary history, hemoglobin, serum iron, transferrin saturation, ferritin, and an occult fecal blood loss investigation, by the immune chromatographic method specific for human hemoglobin were performed. Presence of occult intestinal blood occurred in 8/23 of the breast-fed (plus complementary feed) infants and in 30/64 of the infants who were fed with cow's milk (plus complementary feed) (P=0.449). The comparison of body iron indicators in accordance to positive or negative occult fecal blood, did not show any significant difference in the 23 breast-fed infants. Serum ferritin (median=4.2 ng/mL) was significantly lower (P=0.004) in infants who received whole cow's milk and had positive occult fecal blood, than in those infants who received whole cow's milk but were without occult fecal blood (median=12.1 ng/mL). In breast-fed infants with negative occult fecal blood, iron deficiency severity is not greater than in those with positive results. In infants fed whole cow's milk, occult fecal blood loss is an aggravating factor of iron deficiency.