Search results for "Iron Overload"
showing 10 items of 40 documents
Management of chronic viral hepatitis in patients with thalassemia: recommendations from an international panel.
2010
AbstractChelation therapy with new drugs prevents cardiac damage and improves the survival of thalassemia patients. Liver diseases have emerged as a critical clinical issue. Chronic liver diseases play an important role in the prognosis of thalassemia patients because of the high frequency of viral infections and important role of the liver in regulating iron metabolism. Accurate assessment of liver iron overload is required to tailor iron chelation therapy. The diagnosis of hepatitis B virus– or hepatitis C virus–related chronic hepatitis is required to detect patients who have a high risk of developing liver complications and who may benefit by antiviral therapy. Moreover, clinical manage…
Oxidative imbalance in low/intermediate-1-risk myelodysplastic syndrome patients: The influence of iron overload
2017
Abstract Objective To assess the generation of reactive oxygen species (ROS) and the involvement of the main antioxidant pathways in low/intermediate-1-risk myelodysplastic syndromes (MDS) with iron overload (IOL). Methods We examined the levels of superoxide anion (O2 −), hydrogen peroxide (H2O2), antioxidants (glutathione, GSH; superoxide dismutase, SOD; catalase, CAT; and glutathione peroxidase, GPx), mitochondrial membrane potential (ΔΨm), and by-products of oxidative damage (8-isoprostanes and 8-oxo-7,8-dihydro-2′-deoxyguanosine, 8-oxo-dG) in 42 MDS patients (28 without IOL at diagnosis, and 14 who developed IOL) and 20 healthy subjects. Results Patients with IOL showed higher O2 − lev…
Liver methylene fraction by dual- and triple-echo gradient-echo imaging at 3.0T: Correlation with proton MR spectroscopy and estimation of robustness…
2011
Purpose To assess the systematic errors in liver methylene fraction (LMF) resulting from fat–fat interference effects with dual- and triple-echo gradient-recalled-echo Dual/Triple GRE) sequences and to test the robustness of these sequences after iron overloading. Materials and Methods Forty type-2 diabetic patients underwent LMF measurement by 3.0T 1H magnetic resonance spectroscopy (corrected for T1 and T2 decays) as the reference standard and liver fat fraction (%Fat) measurement by four Dual/Triple GRE sequences with 20° and 60° flip angle (α), corrected for T1 recovery. The same four sequences were repeated in eight patients after ferumoxide injection. Corrections for systematic errors…
Paradoxically, iron overload does not potentiate doxorubicin-induced cardiotoxicity in vitro in cardiomyocytes and in vivo in mice
2015
Doxorubicin (DOX) is known to induce serious cardiotoxicity, which is believed to be mediated by oxidative stress and complex interactions with iron. However, the relationship between iron and DOX-induced cardiotoxicity remains controversial and the role of iron chelation therapy to prevent cardiotoxicity is called into question. Firstly, we evaluated in vitro the effects of DOX in combination with dextran-iron on cell viability in cultured H9c2 cardiomyocytes and EMT-6 cancer cells. Secondly, we used an in vivo murine model of iron overloading (IO) in which male C57BL/6 mice received a daily intra-peritoneal injection of dextran-iron (15mg/kg) for 3weeks (D0-D20) and then (D21) a single su…
Hypothetical molecular mechanisms by which local iron overload facilitates the development of venous leg ulcers and multiple sclerosis lesions.
2008
Summary This paper presents a hypothetical model of role for iron in the development of venous leg ulcers and multiple sclerosis. Elevated concentrations of iron were found in the skin affected by venous hypertension and also in the areas of brain with multiple sclerosis lesions. Individuals with hemochromatosis gene (HFE) mutations: C282Y and H63D, which result in a less efficient transport of iron by macrophages, are characterized by an increased risk for venous leg ulcer and multiple sclerosis. Multiple sclerosis is a T cell-mediated disease, and T cells probably participate in the development of venous ulcers. This deleterious role of ferric ions could be related to the regulation of T …
Iron bioavailability in iron-fortified cereal foods: The contribution of in vitro studies
2015
Iron deficiency anemia is the most common nutritional deficiency in humans. Not all dietary ingested iron, heme or nonheme, will be available to absorption and negative imbalance between iron requirements and absorption leads to iron deficiency and/or anemia. The recommended iron values usually are based on the genetic and on diet iron-bioavailability, which can be considered as the principal factor that change among the cultures and influences the distinct levels of recommendation among countries. Dietary changes present practical limitations due to be difficult to change food habits. The iron food fortification is considered more cost effective and economically more attractive than iron s…
Hormonal and nutritional control of L‐carnitine uptake in myoblastic C2C12 cells
2008
L-Carnitine plays an important role in skeletal muscle bioenergetics, and its bioavailability and thus its import may be crucial for muscle function. We studied the effect of thyroid hormone, insulin, and iron overload, hormones and nutrients known to alter muscle metabolism, on L-carnitine import into C2C12 cells. We report here L-carnitine uptake is increased by thyroid hormones and decreased by iron. Insulin was found to be ineffective in altering the L-carnitine uptake.
Iron Chelation Therapy in thalassaemia major: a sistematic review with meta-analyses of 1520 patients included on randomized clinical trials
2011
The effectiveness of deferoxamine (DFO), deferiprone (DFP), or deferasirox (DFX) in thalassemia major was assessed. Outcomes were reported as means±SD, mean differences with 95% CI, or standardized mean differences. Statistical heterogeneity was tested using χ2 (Q) and I2. Sources of bias and Grading of Recommendations Assessment, Development and Evaluation system (GRADE) were considered. Overall, 1520 patients were included. Only 7.4% of trials were free of bias. Overall measurements suggest low trial quality (GRADE). The meta-analysis suggests lower final liver iron concentrations during associated versus monotherapy treatment (p<0.0001), increases in serum ferritin levels during DFX 5, 1…
Glutathione S Transferase Polymorphisms Influence on Iron Overload in β-Thalassemia Patients
2013
In patients with β-thalassemia iron overload that leads to damage to vital organs is observed. Glutathione S transferase (GST) enzymes have an antioxidant role in detoxification processes of toxic substances. This role is determined genetically. In this study, we correlated GSTT1 and GSTM1 genotypes with iron overload measured with direct and indirect non-invasive methods; in particular, we used serum ferritin and signal intensity of the magnetic resonance image (MRI) in 42 patients with β-thalassemia, which were regularly subjected to chelation and transfusion therapy. Multiplex polymerase chain reaction was used to determine the genotype. The loss of both alleles leads to a decreased valu…