Rayko Evstatiev

FERGIcor, a Randomized Controlled Trial on Ferric Carboxymaltose for Iron Deficiency Anemia in Inflammatory Bowel Disease

BACKGROUND & AIMS Iron deficiency anemia (IDA) is common in chronic diseases and intravenous iron is an effective and recommended treatment. However, dose calculations and inconvenient administration may affect compliance and efficacy. We compared the efficacy and safety of a novel fixed-dose ferric carboxymaltose regimen (FCM) with individually calculated iron sucrose (IS) doses in patients with inflammatory bowel disease (IBD) and IDA. METHODS This randomized, controlled, open-label, multicenter study included 485 patients with IDA (ferritin <100 μg/L, hemoglobin [Hb] 7-12 g/dL [female] or 7-13 g/dL [male]) and mild-to-moderate or quiescent IBD at 88 hospitals and clinics in 14 countries. Patients received either FCM in a maximum of 3 infusions of 1000 or 500 mg iron, or Ganzoni-calculated IS dosages in up to 11 infusions of 200 mg iron. Primary end point was Hb response (Hb increase ≥ 2 g/dL); secondary end points included anemia resolution and iron status normalization by week 12. RESULTS The results of 240 FCM-treated and 235 IS-treated patients were analyzed. More patients with FCM than IS achieved Hb response (150 [65.8%] vs 118 [53.6%]; 12.2% difference, P = .004) or Hb normalization (166 [72.8%] vs 136 [61.8%]; 11.0% difference, P = .015). Both treatments improved quality of life scores by week 12. Study drugs were well tolerated and drug-related adverse events were in line with drug-specific clinical experience. Deviations from scheduled total iron dosages were more frequent in the IS group. CONCLUSIONS The simpler FCM-based dosing regimen showed better efficacy and compliance, as well as a good safety profile, compared with the Ganzoni-calculated IS dose regimen.

Iron sensing and signalling

Iron deficiency is a common condition increasingly diagnosed and treated by gastroenterologists. The most common presentation of iron deficiency is anaemia; however, it is a systemic disorder affecting multiple aspects of health in various organs. Iron is an essential element, with iron-containing proteins exerting a variety of vital functions, including oxygen transport, cellular respiration, intermediary metabolism, regulation of transcription and DNA repair. Major pathways of iron utilisation and production of iron-containing proteins include iron sulphur cluster biosynthesis, haem synthesis and storage within ferritin. The main site of iron absorption is the small intestine, but most iron is recycled by the monocyte–macrophage system via phagocytosis of senescent erythrocytes. Hepcidin, the key iron-regulating peptide binds to the iron exporter ferroportin and leads to its degradation, thereby inhibiting intestinal iron absorption and cellular export. Hepcidin levels are regulated on a transcriptional level by various stimuli, including transferrin saturation, erythropoietic activity, hypoxia and inflammation. Iron deficiency evokes adaptive responses resulting in alteration of cellular metabolism, changes in gene expression, activation of signalling pathways, cell cycle regulation, differentiation and cell death. Such responses are mediated by a number of iron-sensitive signalling pathways, including the IRE/IRP system, HIF and haem signalling. This review provides a molecular perspective for the clinician and highlights important biological aspects of iron deficiency.

Ferric Carboxymaltose Prevents Recurrence of Anemia in Patients With Inflammatory Bowel Disease

BACKGROUND & AIMS Iron-deficiency anemia is the most common systemic complication of inflammatory bowel diseases (IBD). Iron-deficiency anemia recurs frequently and rapidly after iron-replacement therapy in patients with IBD. We performed a randomized, placebo-controlled trial to determine if administration of ferric carboxymaltose (FCM) prevents anemia in patients with IBD and low levels of serum ferritin. METHODS We performed a single-blind, multicenter study of nonanemic patients who had completed the FERGIcor study. Serum levels of ferritin were assessed every second month, and patients were given FCM (total iron dose, 1181 ± 662 mg; n = 105) or placebo (n = 99) when levels decreased to less than 100 μg/L. The primary end point was time to recurrence of anemia within 8 months. Secondary end points included changes of quality of life, disease activity, results from laboratory tests, and adverse events. RESULTS Anemia recurred in 26.7% of subjects given FCM and in 39.4% given placebo. The time to anemia recurrence was longer in the FCM group (hazard ratio, 0.62; 95% confidence interval, 0.38-1.00; P = .049). Markers of body levels of iron increased or remained at normal levels in subjects given FCM (ferritin increased by 30.3 μg/L, transferrin saturation increased by 0.6%) but decreased in the group given placebo (ferritin decreased by 36.1 μg/L, transferrin saturation decreased by 4.0%). Changes in quality of life and disease activity were comparable between groups. Adverse events were reported in 59.0% of the FCM group and 50.5% of the placebo group, and serious adverse events were reported in 6.7% and 8.1%, respectively. CONCLUSIONS FCM prevents recurrence of anemia in patients with IBD, compared with placebo. Nevertheless, the high rate of anemia recurrence warrants optimization of the frequency and requirements for FCM treatment.

Iron deficiency generates secondary thrombocytosis and platelet activation in IBD: the randomized, controlled thromboVIT trial.

Background: Secondary thrombocytosis is a common clinical feature. In patients with cancer, it is a risk factor for venous thromboembolic events. In inflammatory bowel disease (IBD), thrombocytosis is so far considered a marker of active disease and may contribute to the increased thromboembolic risk in this population. Observed effects of iron therapy on normalization of platelet counts led us to hypothesize that iron itself may regulate megakaryopoiesis. Here, we want to test the effect of iron replacement on platelet count and activity in IBD-associated thrombocytosis. Methods: We performed a randomized, single-blinded placebo-controlled trial testing the effect of ferric carboxymaltose (FCM) in patients with IBD with secondary thrombocytosis (platelets > 450 G/L). Changes in platelet counts, hemoglobin, iron parameters, disease activity, megakaryopoietic growth factors, erythropoietin, and platelet activity were assessed. Patients received placebo or up to 1500 mg iron as FCM. Endpoints were evaluated at week 6. Results: A total of 26 patients were included in the study, 15 patients were available for the per protocol analysis. A drop in platelets >25% (primary endpoint) was observed in 4 of 8 (50%, iron group) and 1 of 7 patients (14%, placebo group, P = 0.143). Mean platelet counts dropped on FCM but not on placebo (536 G/L to 411 G/L versus 580 G/L to 559 G/L; P = 0.002). Disease activity and megakaryopoietic growth factors remained unchanged and hemoglobin and iron parameters increased on FCM. The normalization of platelet counts was associated with a decrease in platelet aggregation and P-selectin expression. Conclusion: FCM lowers platelet counts and platelet activation in patients with IBD-associated secondary thrombocytosis.

Effect of Iron Therapy on Platelet Counts in Patients with Inflammatory Bowel Disease-Associated Anemia

Background and Aims Secondary thrombocytosis is a clinical feature of unknown significance. In inflammatory bowel disease (IBD), thrombocytosis is considered a marker of active disease; however, iron deficiency itself may trigger platelet generation. In this study we tested the effect of iron therapy on platelet counts in patients with IBD-associated anemia. Methods Platelet counts were analyzed before and after iron therapy from four prospective clinical trials. Further, changes in hemoglobin, transferrin saturation, ferritin, C-reactive protein, and leukocyte counts, before and after iron therapy were compared. In a subgroup the effect of erythropoietin treatment was tested. The results were confirmed in a large independent cohort (FERGIcor). Results A total of 308 patient records were available for the initial analysis. A dose-depended drop in platelet counts (mean 425 G/L to 320 G/L; p<0.001) was found regardless of the type of iron preparation (iron sulphate, iron sucrose, or ferric carboxymaltose). Concomitant erythropoietin therapy as well as parameters of inflammation (leukocyte counts, C-reactive protein) had no effect on the change in platelet counts. This effect of iron therapy on platelets was confirmed in the FERGIcor study cohort (n=448, mean platelet counts before iron therapy: 383 G/L, after: 310 G/L, p<0.001). Conclusion Iron therapy normalizes elevated platelet counts in patients with IBD-associated anemia. Thus, iron deficiency is an important pathogenetic mechanism of secondary thrombocytosis in IBD.

Mesalamine modulates intercellular adhesion through inhibition of p-21 activated kinase-1

Graphical abstract (a) PAK1 orchestrates mesalamine activity, (b) mesalamine inhibits PAK1; increases membranous E-cadherin and β-catenin; modulates cell adhesion

Thymoquinone attenuates tumor growth in ApcMin mice by interference with Wnt-signaling

BackgroundPatients with familial adenomatous polyposis (FAP) are at increased risk for the development of colorectal cancer. Surgery and chemoprevention are the most effective means to prevent cancer development. Thymoquinone (TQ) is considered the main compound of the volatile Nigella sativa seed oil and has been reported to possess anticarcinogenic properties. In this study we evaluated the chemopreventive properties of TQ in a mouse model of FAP.MethodsAPCMin mice were fed with chow containing 37.5 mg/kg or 375 mg/kg TQ for 12 weeks. H&E stained intestine tissue sections were assessed for tumor number, localization, size, and grade. Immunohistochemistry for β-catenin, c-myc, Ki-67 and TUNEL-staining was performed to investigate TQ’s effect on major colorectal cancer pathways. TQ’s impact on GSK-3β and β-catenin were studied in RKO cells.Results375 mg/kg but not 37.5 mg/kg TQ decreased the number of large polyps in the small intestine of APCMin mice. TQ induced apoptosis in the neoplastic tissue but not in the normal mucosa. Furthermore, upon TQ treatment, β-catenin was retained at the membrane and c-myc decreased in the nucleus, which was associated with a reduced cell proliferation in the villi. In vitro, TQ activated GSK-3β, which induced membranous localization of β-catenin and reduced nuclear c-myc expression.ConclusionsIn summary, TQ interferes with polyp progression in ApcMin mice through induction of tumor-cell specific apoptosis and by modulating Wnt signaling through activation of GSK-3β. Nigella sativa oil (or TQ) might be useful as nutritional supplement to complement surgery and chemoprevention in FAP.

Iron deficiency alters megakaryopoiesis and platelet phenotype independent of thrombopoietin

Iron deficiency is a common cause of reactive thrombocytosis, however, the exact pathways have not been revealed. Here we aimed to study the mechanisms behind iron deficiency‐induced thrombocytosis. Within few weeks, iron‐depleted diet caused iron deficiency in young Sprague–Dawley rats, as reflected by a drop in hemoglobin, mean corpuscular volume, hepatic iron content and hepcidin mRNA in the liver. Thrombocytosis established in parallel. Moreover, platelets produced in iron deficient animals displayed a higher mean platelet volume and increased aggregation. Bone marrow studies revealed subtle alterations that are suggestive of expansion of megakaryocyte progenitors, an increase in megakaryocyte ploidy and accelerated megakaryocyte differentiation. Iron deficiency did not alter the production of hematopoietic growth factors such as thrombopoietin, interleukin 6 or interleukin 11. Megakaryocytic cell lines grown in iron‐depleted conditions exhibited reduced proliferation but increased ploidy and cell size. Our data suggest that iron deficiency increases megakaryopoietic differentiation and alters platelet phenotype without changes in megakaryocyte growth factors, specifically TPO. Iron deficiency‐induced thrombocytosis may have evolved to maintain or increase the coagulation capacity in conditions with chronic bleeding. Am. J. Hematol. 89:524–529, 2014.

PAK1 modulates a PPARγ/NF-κB cascade in intestinal inflammation.

P21-activated kinases (PAKs) are multifunctional effectors of Rho GTPases with both kinase and scaffolding activity. Here, we investigated the effects of inflammation on PAK1 signaling and its role in colitis-driven carcinogenesis. PAK1 and p-PAK1 (Thr423) were assessed by immunohistochemistry, immunofluorescence, and Western blot. C57BL6/J wildtype mice were treated with a single intraperitoneal TNFα injection. Small intestinal organoids from these mice and from PAK1-KO mice were cultured with TNFα. NF-κB and PPARγ were analyzed upon PAK1 overexpression and silencing for transcriptional/translational regulation. PAK1 expression and activation was increased on the luminal intestinal epithelial surface in inflammatory bowel disease and colitis-associated cancer. PAK1 was phosphorylated upon treatment with IFNγ, IL-1β, and TNFα. In vivo, mice administered with TNFα showed increased p-PAK1 in intestinal villi, which was associated with nuclear p65 and NF-κB activation. p65 nuclear translocation downstream of TNFα was strongly inhibited in PAK1-KO small intestinal organoids. PAK1 overexpression induced a PAK1–p65 interaction as visualized by co-immunoprecipitation, nuclear translocation, and increased NF-κB transactivation, all of which were impeded by kinase-dead PAK1. Moreover, PAK1 overexpression downregulated PPARγ and mesalamine recovered PPARγ through PAK1 inhibition. On the other hand PAK1 silencing inhibited NF-κB, which was recovered using BADGE, a PPARγ antagonist. Altogether these data demonstrate that PAK1 overexpression and activation in inflammation and colitis-associated cancer promote NF-κB activity via suppression of PPARγ in intestinal epithelial cells.

Iron metabolism and iron supplementation in cancer patients

SummaryIron deficiency and iron deficiency-associated anemia are common complications in cancer patients. Most iron deficient cancer patients present with functional iron deficiency (FID), a status with adequate storage iron, but insufficient iron supply for erythroblasts and other iron dependent tissues. FID is the consequence of the cancer-associated cytokine release, while in absolute iron deficiency iron stores are depleted resulting in similar but often more severe symptoms of insufficient iron supply. Here we present a short review on the epidemiology, pathophysiology, diagnosis, clinical symptoms, and treatment of iron deficiency in cancer patients. Special emphasis is given to intravenous iron supplementation and on the benefits and limitations of different formulations. Based on these considerations and recommendations from current international guidelines we developed recommendations for clinical practice and classified the level of evidence and grade of recommendation according to the principles of evidence-based medicine.