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1.
J Pediatr Hematol Oncol ; 44(1): e26-e34, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34986131

RESUMEN

BACKGROUND: Studies on the increased body iron load in patients with thalassemia major have thoroughly demonstrated the problems caused by iron overload. In patients who undergo hematopoietic stem cell transplantation (HSCT) as curative therapy, iron overload continues long after transplantation. There are few pediatric studies on chelation therapy in the posttransplant period. In this study, we present the outcomes of our patients who received posttransplant oral chelation therapy. PATIENTS AND METHODS: This retrospective observational study evaluated the outcomes of pediatric patients with thalassemia major who used oral chelation therapy after allogeneic HSCT at the Akdeniz University Pediatric Bone Marrow Unit between January 2008 and October 2019. RESULTS: Deferasirox therapy was initiated in 58 pediatric patients who underwent HSCT for thalassemia. Pretreatment mean serum ferritin was 2166±1038 ng/mL. Treatment was initiated at a mean of 12±6.7 months after transplantation and continued for a mean of 15.7±11.5 months. At treatment discontinuation, the mean serum ferritin was 693±405 ng/mL and the mean reduction was -1472.75±1121.09 ng/mL (P<0.001 vs. posttreatment). Serum ferritin was below 500 ng/mL in 52% of the patients at treatment discontinuation. Manageable side effects such as nausea, vomiting, liver enzyme elevation, and proteinuria were observed in 17% of the patients, while one patient developed ototoxicity. CONCLUSIONS: Deferasirox therapy effectively reduces iron overload in the posttransplant period. Studies evaluating the effects of early treatment on the graft may help to establish guidelines for posttransplant chelation therapy. Clear guidelines are needed regarding when to initiate and discontinue treatment.


Asunto(s)
Deferasirox/administración & dosificación , Trasplante de Células Madre Hematopoyéticas , Quelantes del Hierro/administración & dosificación , Sobrecarga de Hierro/terapia , Talasemia/terapia , Adolescente , Aloinjertos , Niño , Preescolar , Deferasirox/efectos adversos , Femenino , Ferritinas/sangre , Humanos , Quelantes del Hierro/efectos adversos , Sobrecarga de Hierro/sangre , Masculino , Estudios Retrospectivos , Talasemia/sangre
5.
J Hepatol ; 76(3): 568-576, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34748893

RESUMEN

BACKGROUND & AIMS: Ferroportin disease is a rare genetic iron overload disorder which may be underdiagnosed, with recent data suggesting it occurs at a higher prevalence than suspected. Costs and the lack of defined criteria to prompt genetic testing preclude large-scale molecular screening. Hence, we aimed to develop a readily available scoring system to promote and enhance ferroportin disease screening. METHODS: Our derivation cohort included probands tested for ferroportin disease from 2008 to 2016 in our rare disease network. Data were prospectively recorded. Univariate and multivariate logistic regression were used to determine significant criteria, and odds ratios were used to build a weighted score. A cut-off value was defined using a ROC curve with a predefined aim of 90% sensitivity. An independent cohort was used for cross validation. RESULTS: Our derivation cohort included 1,306 patients. Mean age was 55±14 years, ferritin 1,351±1,357 µg/L, and liver iron concentration (LIC) 166±77 µmol/g. Pathogenic variants (n = 32) were identified in 71 patients. In multivariate analysis: female sex, younger age, higher ferritin, higher LIC and the absence of hypertension or diabetes were significantly associated with the diagnosis of ferroportin disease (AUROC in whole derivation cohort 0.83 [0.78-0.88]). The weighted score was based on sex, age, the presence of hypertension or diabetes, ferritin level and LIC. An AUROC of 0.83 (0.77-0.88) was obtained in the derivation cohort without missing values. Using 9.5 as a cut-off, sensitivity was 93.6 (91.7-98.3) %, specificity 49.5 (45.5-53.6) %, positive likelihood ratio 1.8 (1.6-2.0) and negative likelihood ratio 0.17 (0.04-0.37). CONCLUSION: We describe a readily available score with simple criteria and good diagnostic performance that could be used to screen patients for ferroportin disease in routine clinical practice. LAY SUMMARY: Increased iron burden associated with metabolic syndrome is a very common condition. Ferroportin disease is a dominant genetic iron overload disorder whose prevalence is higher than initially thought. They can be difficult to distinguish from each other, but the limited availability of genetic testing and the lack of definitive guidelines prevent adequate screening. We herein describe a simple and definitive clinical score to help clinicians decide whether to perform genetic testing.


Asunto(s)
Proteínas de Transporte de Catión/análisis , Hemocromatosis/diagnóstico , Proyectos de Investigación/normas , Anciano , Proteínas de Transporte de Catión/sangre , Estudios de Cohortes , Femenino , Hemocromatosis/sangre , Humanos , Hierro/metabolismo , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/complicaciones , Modelos Logísticos , Masculino , Tamizaje Masivo/métodos , Tamizaje Masivo/estadística & datos numéricos , Persona de Mediana Edad , Curva ROC , Proyectos de Investigación/estadística & datos numéricos
6.
Blood Cells Mol Dis ; 92: 102617, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34656943

RESUMEN

Abnormally high serum ferritin levels have been reported during pediatric ECMO, attributed to frequent red blood cell transfusion and suggestive of iron overload. However, the utility of ferritin for diagnosing iron overload is complicated by its response as an acute-phase reactant. In this study, we aimed to assess the utility of ferritin for diagnosing ECMO-related iron overload, with secondary aims of understanding its relationship with inflammation and erythropoiesis. Ferritin was elevated in all pediatric ECMO runs (median 459 ng/ml, IQR = 327.3-694.4). While intermittent elevations in serum iron were observed, all normalized prior to decannulation. Unreported previously, erythropoietin (EPO) remained well above normative values prior to and throughout ECMO runs, despite frequent transfusion and exposure to hyperoxia. Ferritin correlated poorly with serum iron [r(80) = 0.05, p = 0.65], but correlated well with IL-6 [r(76) = 0.48, p < 0.001] and EPO [r(81) = 0.55, p < 0.001]. We suggest that serum ferritin is a poor biomarker of iron overload in ECMO patients, and that future investigation into its relationship with EPO is warranted.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Ferritinas/sangre , Sobrecarga de Hierro/sangre , Preescolar , Eritropoyetina/sangre , Oxigenación por Membrana Extracorpórea/efectos adversos , Humanos , Lactante , Recién Nacido , Hierro/sangre , Sobrecarga de Hierro/diagnóstico , Sobrecarga de Hierro/etiología , Proyectos Piloto , Estudios Prospectivos
7.
Ann Hematol ; 100(12): 2909-2917, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34432101

RESUMEN

Tissue iron overload is a life-threatening scenario in children with transfusion-dependent ß-thalassemia major, miRNAs that are involved in iron hemostasis could serve as therapeutic targets for control of iron overload. We aimed to find out the association between three iron-related miRNAs "miR-let-7d, miR-122, and miR-200b" and excess iron in tissues, in transfusion-dependent ß-thalassemia major patients. Circulating miRNA expressions are measured in peripheral blood (PB) samples using qPCR of transfusion-dependent (TDT) ß-thalassemia patients (n = 140) and normalized to non-transfusion-dependent (NTDT) ß-thalassemia (n = 45). Results revealed that plasma expression levels of miR-let-7d and miR-200b were significantly downregulated in TDT patients; however, miR-122 was upregulated. In terms of tissue iron load, aberrant expression of miRNAs was significantly associated with increased-iron accumulation in hepatic and cardiac tissues. We concluded that circulating miRNAs are strong candidates that associate iron hemostasis in transfusion-dependent ß-thalassemia major patients. And by extension, targeting miR-let-7d, miR-122, and miR-200 might serve as novel sensitive, specific and non-invasive predictor biomarkers for cellular damage under condition of tissue iron excess.


Asunto(s)
Sobrecarga de Hierro/complicaciones , MicroARNs/sangre , Talasemia beta/complicaciones , Adolescente , Transfusión Sanguínea , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Sobrecarga de Hierro/sangre , Masculino , Talasemia beta/sangre , Talasemia beta/terapia
9.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1866(10): 159004, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34245925

RESUMEN

The atherosclerosis "iron hypothesis" generates a fair amount of debate since it has been proposed. Here, we revisited the "iron hypothesis" by examining whether dietary iron overload would intensify iron deposition in plaques and thus lead to further exacerbation of atherosclerosis in apolipoprotein E knockout (ApoE KO) mice. ApoE KO mice were fed either a normal chow diet (ND) or a high fat diet (HFD) supplemented with or without 2% carbonyl iron (Fe) for 16 weeks. However, contrary to our assumption, dietary iron overloading did not intensify, but rather diminished the atherosclerotic lesion area by 65.3%, which was accompanied by significantly decreased serum total cholesterol, triglyceride and low-density lipoprotein cholesterol contents, together with hepatic lipid accumulation decline, despite the evident existence of aortic iron accumulation and the typical signs of iron overload in ApoE KO mice. Using isobaric tag for absolute quantification (iTRAQ) proteomics approach, hepatic CD36 and fatty acid binding proteins-mediated fatty acid (FA) uptake and trafficking impairment were identified as the key potential pathomechanisms by which iron overload diminishes atherosclerotic lesions. Furthermore, downstream hepatic FA de novo biosynthesis was enhanced and FA oxidation was inhibited to compensate for the FA deficiency triggered by iron overload-impaired fatty acid uptake and trafficking. Our findings suggested that dietary iron overload is not atherogenic in ApoE KO mice, and more research efforts are warranted to revisit the "iron hypothesis" of atherosclerosis.


Asunto(s)
Aterosclerosis/dietoterapia , Dieta Alta en Grasa/efectos adversos , Compuestos de Hierro/administración & dosificación , Sobrecarga de Hierro/inducido químicamente , Administración Oral , Animales , Aterosclerosis/sangre , Aterosclerosis/etiología , Aterosclerosis/metabolismo , LDL-Colesterol/sangre , LDL-Colesterol/metabolismo , Suplementos Dietéticos , Modelos Animales de Enfermedad , Femenino , Humanos , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/metabolismo , Metabolismo de los Lípidos , Lipogénesis/fisiología , Masculino , Ratones , Ratones Noqueados para ApoE , Triglicéridos/sangre , Triglicéridos/metabolismo
10.
Food Funct ; 12(16): 7321-7328, 2021 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-34173816

RESUMEN

This study proposed to investigate the effect of Ilex paraguariensis infusion on the absorption of non-heme iron in hereditary hemochromatosis (HH) patients with the HFE genotype. A two-way randomized, controlled, crossover trial was conducted on patients, aged 29-69 years, undergoing maintenance therapy. Fourteen HFE-HH patients ingested a meal containing 11.4 mg iron and 200 mL either of water (control) or of Ilex paraguariensis leaf infusion. The beverages were offered in random order, at intervals separated by a washout period of 7 days. Active surveillance showed no adverse effects. Blood samples were drawn shortly before and 1, 2, 3, and 4 h after the meal for serum iron measurement. A significant reduction in the postprandial serum iron was observed for HH patients after intake of the Ilex paraguariensis infusion (area under the curve (AUC) expressed as mean ± SEM: 173.3 ± 44.7 µmol h-1 L-1) compared to water (1449.4 ± 241.5 µmol h-1 L-1) (p < 0.001). In summary, intake of Ilex paraguariensis leaf infusion significantly inhibited the absorption of iron in patients with HH and, therefore, should be considered as a potential adjuvant for iron overload control.


Asunto(s)
Hemocromatosis/sangre , Ilex paraguariensis/metabolismo , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/prevención & control , Extractos Vegetales/farmacología , Hojas de la Planta/metabolismo , Adulto , Anciano , Bebidas , Estudios Cruzados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Extractos Vegetales/sangre
11.
Sci Rep ; 11(1): 12581, 2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-34131221

RESUMEN

Deferasirox (DFX) is the newest among three different chelators available to treat iron overload in iron-loading anaemias, firstly released as Dispersible Tablets (DT) and more recently replaced by Film-Coated Tablets (FCT). In this retrospective observational study, pharmacokinetics, pharmacodynamics, and safety features of DFX treatment were analyzed in 74 patients that took both formulations subsequently under clinical practice conditions. Bioavailability of DFX FCT compared to DT resulted higher than expected [Cmax: 99.5 (FCT) and 69.7 (DT) µMol/L; AUC: 1278 (FCT) and 846 (DT), P < 0.0001]. DFX FCT was also superior in scalability among doses. After one year of treatment for each formulation, no differences were observed between the treatments in the overall iron overload levels; however, DFX FCT but not DT showed a significant dose-response correlation [Spearman r (dose-serum ferritin variation): - 0.54, P < 0.0001]. Despite being administered at different dosages, the long-term safety profile was not different between formulations: a significant increase in renal impairment risk was observed for both treatments and it was reversible under strict monitoring (P < 0.002). Altogether, these data constitute a comprehensive comparison of DFX formulations in thalassaemia and other iron-loading anaemias, confirming the effectiveness and safety characteristics of DFX and its applicability for treatment tailoring.


Asunto(s)
Anemia/tratamiento farmacológico , Deferasirox/administración & dosificación , Sobrecarga de Hierro/tratamiento farmacológico , Talasemia/tratamiento farmacológico , Adulto , Anemia/sangre , Anemia/epidemiología , Anemia/patología , Terapia por Quelación/tendencias , Deferasirox/farmacocinética , Femenino , Ferritinas/sangre , Humanos , Hierro/sangre , Hierro/metabolismo , Quelantes del Hierro/administración & dosificación , Quelantes del Hierro/farmacocinética , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/epidemiología , Sobrecarga de Hierro/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Talasemia/sangre , Talasemia/epidemiología , Talasemia/patología
12.
CNS Neurosci Ther ; 27(10): 1118-1126, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34145764

RESUMEN

AIMS: Iron released from lysed red blood cells within the hematoma plays a role in intracerebral hemorrhage (ICH)-related neurotoxicity. This study utilizes magnetic resonance imaging (MRI) to examine the time course, extent of erythrolysis, and its correlation with perihematomal iron accumulation and white matter loss. METHODS: The feasibility of assessing proportional erythrolysis using T2* MRI was examined using pig blood phantoms with specified degrees of erythrolysis. Fifteen prospectively enrolled ICH patients had MRIs (3-Tesla) at days 1-3, 14, and 30 (termed early, subacute, and late periods, respectively). Measurement was performed on T2*, 1/T2*, and fractional anisotropy (FA) maps. RESULTS: Pig blood phantoms showed a linear relationship between 1/T2* signal and percent erythrolysis. MRI on patients showed an increase in erythrolysis within the hematoma between the early and subacute phases after ICH, almost completing by day 14. Although perihematomal iron overload (IO) correlated with the erythrolysis extent and hematoma volume at days 14 and 30, perihematomal white matter (WM) loss significantly correlated with both, only at day 14. CONCLUSION: MRI may reliably assess the portion of the hematoma that lyses over time after ICH. Perihematomal IO and WM loss correlate with both the erythrolysis extent and hematoma volume in the early and subacute periods following ICH.


Asunto(s)
Hemorragia Cerebral/sangre , Eritrocitos/patología , Sobrecarga de Hierro/sangre , Sustancia Blanca/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Animales , Hemorragia Cerebral/diagnóstico por imagen , Femenino , Humanos , Sobrecarga de Hierro/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fantasmas de Imagen , Porcinos , Adulto Joven
13.
Cochrane Database Syst Rev ; 5: CD011817, 2021 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-34028001

RESUMEN

BACKGROUND: Reference standard indices of iron deficiency and iron overload are generally invasive, expensive, and can be unpleasant or occasionally risky. Ferritin is an iron storage protein and its concentration in the plasma or serum reflects iron stores; low ferritin indicates iron deficiency, while elevated ferritin reflects risk of iron overload. However, ferritin is also an acute-phase protein and its levels are elevated in inflammation and infection. The use of ferritin as a diagnostic test of iron deficiency and overload is a common clinical practice. OBJECTIVES: To determine the diagnostic accuracy of ferritin concentrations (serum or plasma) for detecting iron deficiency and risk of iron overload in primary and secondary iron-loading syndromes. SEARCH METHODS: We searched the following databases (10 June 2020): DARE (Cochrane Library) Issue 2 of 4 2015, HTA (Cochrane Library) Issue 4 of 4 2016, CENTRAL (Cochrane Library) Issue 6 of 12 2020, MEDLINE (OVID) 1946 to 9 June 2020, Embase (OVID) 1947 to week 23 2020, CINAHL (Ebsco) 1982 to June 2020, Web of Science (ISI) SCI, SSCI, CPCI-exp & CPCI-SSH to June 2020, POPLINE 16/8/18, Open Grey (10/6/20), TRoPHI (10/6/20), Bibliomap (10/6/20), IBECS (10/6/20), SCIELO (10/6/20), Global Index Medicus (10/6/20) AIM, IMSEAR, WPRIM, IMEMR, LILACS (10/6/20), PAHO (10/6/20), WHOLIS 10/6/20, IndMED (16/8/18) and Native Health Research Database (10/6/20). We also searched two trials registers and contacted relevant organisations for unpublished studies. SELECTION CRITERIA: We included all study designs seeking to evaluate serum or plasma ferritin concentrations measured by any current or previously available quantitative assay as an index of iron status in individuals of any age, sex, clinical and physiological status from any country. DATA COLLECTION AND ANALYSIS: We followed standard Cochrane methods. We designed the data extraction form to record results for ferritin concentration as the index test, and bone marrow iron content for iron deficiency and liver iron content for iron overload as the reference standards. Two other authors further extracted and validated the number of true positive, true negative, false positive, false negative cases, and extracted or derived the sensitivity, specificity, positive and negative predictive values for each threshold presented for iron deficiency and iron overload in included studies. We assessed risk of bias and applicability using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool. We used GRADE assessment to enable the quality of evidence and hence strength of evidence for our conclusions. MAIN RESULTS: Our search was conducted initially in 2014 and updated in 2017, 2018 and 2020 (10 June). We identified 21,217 records and screened 14,244 records after duplicates were removed. We assessed 316 records in full text. We excluded 190 studies (193 records) with reasons and included 108 studies (111 records) in the qualitative and quantitative analysis. There were 11 studies (12 records) that we screened from the last search update and appeared eligible for a future analysis. We decided to enter these as awaiting classification. We stratified the analysis first by participant clinical status: apparently healthy and non-healthy populations. We then stratified by age and pregnancy status as: infants and children, adolescents, pregnant women, and adults. Iron deficiency We included 72 studies (75 records) involving 6059 participants. Apparently healthy populations Five studies screened for iron deficiency in people without apparent illness. In the general adult population, three studies reported sensitivities of 63% to 100% at the optimum cutoff for ferritin, with corresponding specificities of 92% to 98%, but the ferritin cutoffs varied between studies. One study in healthy children reported a sensitivity of 74% and a specificity of 77%. One study in pregnant women reported a sensitivity of 88% and a specificity of 100%. Overall confidence in these estimates was very low because of potential bias, indirectness, and sparse and heterogenous evidence. No studies screened for iron overload in apparently healthy people. People presenting for medical care There were 63 studies among adults presenting for medical care (5042 participants). For a sample of 1000 subjects with a 35% prevalence of iron deficiency (of the included studies in this category) and supposing a 85% specificity, there would be 315 iron-deficient subjects correctly classified as having iron deficiency and 35 iron-deficient subjects incorrectly classified as not having iron deficiency, leading to a 90% sensitivity. Thresholds proposed by the authors of the included studies ranged between 12 to 200 µg/L. The estimated diagnostic odds ratio was 50. Among non-healthy adults using a fixed threshold of 30 µg/L (nine studies, 512 participants, low-certainty evidence), the pooled estimate for sensitivity was 79% with a 95% confidence interval of (58%, 91%) and specificity of 98%, with a 95% confidence interval of (91%, 100%). The estimated diagnostic odds ratio was 140, a relatively highly informative test. Iron overload We included 36 studies (36 records) involving 1927 participants. All studies concerned non-healthy populations. There were no studies targeting either infants, children, or pregnant women. Among all populations (one threshold for males and females; 36 studies, 1927 participants, very low-certainty evidence): for a sample of 1000 subjects with a 42% prevalence of iron overload (of the included studies in this category) and supposing a 65% specificity, there would be 332 iron-overloaded subjects correctly classified as having iron overload and 85 iron-overloaded subjects incorrectly classified as not having iron overload, leading to a 80% sensitivity. The estimated diagnostic odds ratio was 8. AUTHORS' CONCLUSIONS: At a threshold of 30 micrograms/L, there is low-certainty evidence that blood ferritin concentration is reasonably sensitive and a very specific test for iron deficiency in people presenting for medical care. There is very low certainty that high concentrations of ferritin provide a sensitive test for iron overload in people where this condition is suspected. There is insufficient evidence to know whether ferritin concentration performs similarly when screening asymptomatic people for iron deficiency or overload.


Asunto(s)
Anemia Ferropénica/sangre , Ferritinas/sangre , Sobrecarga de Hierro/sangre , Adolescente , Adulto , Anciano , Anemia Ferropénica/diagnóstico , Sesgo , Biomarcadores/sangre , Niño , Preescolar , Femenino , Humanos , Lactante , Sobrecarga de Hierro/diagnóstico , Masculino , Persona de Mediana Edad , Embarazo , Mujeres Embarazadas , Sensibilidad y Especificidad , Adulto Joven
14.
Mol Metab ; 51: 101235, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33872860

RESUMEN

OBJECTIVE: The molecular pathogenesis of late complications associated with type 2 diabetes mellitus (T2DM) is not yet fully understood. While high glucose levels indicated by increased HbA1c only poorly explain disease progression and late complications, a pro-inflammatory status, oxidative stress, and reactive metabolites generated by metabolic processes were postulated to be involved. Individuals with metabolic syndrome (MetS) frequently progress to T2DM, whereby 70% of patients with T2DM show non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of MetS, and insulin resistance (IR). Epidemiological studies have shown that T2DM and steatosis are associated with alterations in iron metabolism and hepatic iron accumulation. Excess free iron triggers oxidative stress and a switch towards a macrophage pro-inflammatory status. However, so far it remains unclear whether hepatic iron accumulation plays a causative role in the generation of IR and T2DM or whether it is merely a manifestation of altered hepatic metabolism. To address this open question, we generated and characterized a mouse model of T2DM with IR, steatosis, and iron overload. METHODS: Leprdb/db mice hallmarked by T2DM, IR and steatosis were crossed with Fpnwt/C326S mice with systemic iron overload to generate Leprdb/db/Fpnwt/C326S mice. The resulting progeny was characterized for major diabetic and iron-related parameters. RESULTS: We demonstrated that features associated with T2DM in Leprdb/db mice, such as obesity, steatosis, or IR, reduce the degree of tissue iron overload in Fpnwt/C326S mice, suggesting an 'iron resistance' phenotype. Conversely, we observed increased serum iron levels that strongly exceeded those in the iron-overloaded Fpnwt/C326S mice. Increased hepatic iron levels induced oxidative stress and lipid peroxidation and aggravated IR, as indicated by diminished IRS1 phosphorylation and AKT activation. Additionally, in the liver, we observed gene response patterns indicative of de novo lipogenesis and increased gluconeogenesis as well as elevated free glucose levels. Finally, we showed that iron overload in Leprdb/db/Fpnwt/C326S mice enhances microvascular complications observed in retinopathy, suggesting that iron accumulation can enhance diabetic late complications associated with the liver and the eye. CONCLUSION: Taken together, our data show that iron causes the worsening of symptoms associated with the MetS and T2DM. These findings imply that iron depletion strategies together with anti-diabetic drugs may ameliorate IR and diabetic late complications.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Resistencia a la Insulina , Sobrecarga de Hierro/metabolismo , Hierro/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Animales , Glucemia/análisis , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/genética , Modelos Animales de Enfermedad , Humanos , Hierro/sangre , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/genética , Peroxidación de Lípido , Hígado/metabolismo , Hígado/patología , Masculino , Ratones , Ratones Transgénicos , Enfermedad del Hígado Graso no Alcohólico/sangre , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Estrés Oxidativo , Receptores de Leptina/genética
15.
J Cell Physiol ; 236(11): 7544-7553, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33855731

RESUMEN

Iron overload is tightly connected with metabolic disorders. Excess iron in the adipose and its roles in dyslipidemia are of interest to be identified. In acute iron overload mice receiving intraperitoneal injection of 100 mg/kg/day dextran-iron for 5 days, the epididymis adipose showed a remarkable increase in iron. Serum triglyceride and low-density lipoprotein cholesterol (LDL-C) levels were increased and high-density lipoprotein cholesterol (HDL-C) level was decreased, while serum alkaline phosphatase, aspartate aminotransferase, glucose, and insulin were not affected. The serum-cytokine-microarray showed that adipocytokines, including adiponectin, leptin, and resistin were significantly decreased. Other serum cytokines, including pro-insulin cytokines, inflammatory cytokines, chemokines, and growth factors were not changed, except that ghrelin and chemokine RANTES were increased. Iron overload decreased expressions of adiponectin and leptin both in vivo and in vitro. Intraperitoneal injection of recombinant leptin at 1 µg/g in acute iron overload mice had no significant effects on serum levels of TC, TG, HDL-C, and LDL-C, while intraperitoneal injection of recombinant adiponectin at 3 µg/g partially restored serum TG level through improving activities of lipoprotein lipase and hepatic lipase, but abnormal serum LDL-C and HDL-C were not redressed, suggesting other mechanisms also existed. In conclusion, the adipose responds to iron overload at an early stage to interfere with lipid metabolism by secreting adipocytokines, which may further affect glucose metabolism, inflammation, and other iron overload-induced effects on the body.


Asunto(s)
Adipocitos/metabolismo , Adiponectina/sangre , Dislipidemias/sangre , Sobrecarga de Hierro/sangre , Hierro/sangre , Hígado/metabolismo , Triglicéridos/sangre , Células 3T3-L1 , Adipocitos/efectos de los fármacos , Adiponectina/farmacología , Animales , Modelos Animales de Enfermedad , Dislipidemias/etiología , Sobrecarga de Hierro/inducido químicamente , Complejo Hierro-Dextran , Leptina/sangre , Leptina/farmacología , Ratones , Ratones Endogámicos C57BL
17.
Commun Biol ; 4(1): 156, 2021 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-33536631

RESUMEN

Iron is essential for many biological functions and iron deficiency and overload have major health implications. We performed a meta-analysis of three genome-wide association studies from Iceland, the UK and Denmark of blood levels of ferritin (N = 246,139), total iron binding capacity (N = 135,430), iron (N = 163,511) and transferrin saturation (N = 131,471). We found 62 independent sequence variants associating with iron homeostasis parameters at 56 loci, including 46 novel loci. Variants at DUOX2, F5, SLC11A2 and TMPRSS6 associate with iron deficiency anemia, while variants at TF, HFE, TFR2 and TMPRSS6 associate with iron overload. A HBS1L-MYB intergenic region variant associates both with increased risk of iron overload and reduced risk of iron deficiency anemia. The DUOX2 missense variant is present in 14% of the population, associates with all iron homeostasis biomarkers, and increases the risk of iron deficiency anemia by 29%. The associations implicate proteins contributing to the main physiological processes involved in iron homeostasis: iron sensing and storage, inflammation, absorption of iron from the gut, iron recycling, erythropoiesis and bleeding/menstruation.


Asunto(s)
Anemia Ferropénica/genética , Sitios Genéticos , Variación Genética , Sobrecarga de Hierro/genética , Hierro/sangre , Anemia Ferropénica/sangre , Anemia Ferropénica/diagnóstico , Biomarcadores/sangre , Dinamarca , Ferritinas/sangre , Estudio de Asociación del Genoma Completo , Genotipo , Homeostasis , Humanos , Islandia , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/diagnóstico , Fenotipo , Medición de Riesgo , Factores de Riesgo , Transferrina/metabolismo , Reino Unido
18.
Int J Hematol ; 113(4): 537-546, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33400141

RESUMEN

Red blood cell (RBC) transfusion is an effective therapy for anemia, but repeated transfusions may cause iron overload-related damage to various organs. Iron chelation therapy, now widely available for patients who have received transfusions, is expected to reduce organ damage even in patients who received many transfusions. Therefore, determining when to start iron chelation therapy is important. In guidelines for iron chelation therapy, the serum ferritin level has been widely accepted as a practical marker for estimating iron overload. However, guidelines recommend multiple measurements of serum ferritin, because levels often fluctuate. Here, we investigated the usefulness of glycosylated ferritin as a marker of iron overload using a cohort consisted of 103 patients who had a total ferritin value over 1000 ng/mL. We found that the volume of RBCs transfused was clearly associated with the glycosylated ferritin level. We also found that acute inflammation, as represented by C-reactive protein values, was associated with increased non-glycosylated ferritin and that patients with hematopoietic diseases had higher glycosylated ferritin levels, possibly because of repeated RBC transfusions. We thus conclude that glycosylated ferritin may be an improved marker for predicting iron overload status.


Asunto(s)
Biomarcadores , Ferritinas/sangre , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/diagnóstico , Anciano , Transfusión Sanguínea , Comorbilidad , Transfusión de Eritrocitos , Femenino , Humanos , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/terapia , Masculino , Persona de Mediana Edad , Pronóstico
19.
J Clin Endocrinol Metab ; 106(4): e1559-e1573, 2021 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-33462622

RESUMEN

CONTEXT: Functional hyperandrogenism may be associated with a mild increase in body iron stores. Iron depletion exerts a beneficial effect on metabolic endpoints in other iron overload states. OBJECTIVES: (i) To determine the effect of iron depletion on the insulin sensitivity and frequency of abnormal glucose tolerance in patients with functional hyperandrogenism submitted to standard therapy with combined oral contraceptives (COC). ii) To assess the overall safety of this intervention. DESIGN: Randomized, parallel, open-label, clinical trial. SETTING: Academic hospital. PATIENTS: Adult women with polycystic ovary syndrome or idiopathic hyperandrogenism. INTERVENTION: After a 3-month run-in period of treatment with 35 µg ethinylestradiol plus 2 mg cyproterone acetate, participants were randomized (1:1) to 3 scheduled bloodlettings or observation for another 9 months. MAIN OUTCOME MEASURES: Changes in insulin sensitivity index and frequency of prediabetes/diabetes, and percentage of women in whom bloodletting resulted in plasma hemoglobin <120 g/L and/or hematocrit <0.36. RESULTS: From 2015 to 2019, 33 women were included by intention-to-treat. During the follow-up, insulin sensitivity did not change in the whole group of women or between study arms [mean of the differences (MD): 0.0 (95%CI: -1.6 to 1.6)]. Women in the experimental arm showed a similar odds of having prediabetes/diabetes than women submitted to observation [odds ratio: 0.981 (95%CI: 0.712 to 1.351)]. After bloodletting, 4 (21.1%) and 2 women (10.5%) in the experimental arm had hemoglobin (Hb) levels <120 g/L and hematocrit (Hct) values <0.36, respectively, but none showed Hb <110 g/L or Hct <0.34. CONCLUSIONS: Scheduled bloodletting does not improve insulin sensitivity in women with functional hyperandrogenism on COC.


Asunto(s)
Hiperandrogenismo/sangre , Sobrecarga de Hierro/sangre , Adulto , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Hiperandrogenismo/complicaciones , Resistencia a la Insulina , Sobrecarga de Hierro/complicaciones , Flebotomía , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/complicaciones , Adulto Joven
20.
Int J Mol Sci ; 23(1)2021 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-35008695

RESUMEN

During infections, the host redistributes iron in order to starve pathogens from this nutrient. Several proteins are involved in iron absorption, transport, and storage. Ferritin is the most important iron storage protein. It is composed of variable proportions of two peptides, the L- and H-ferritins (FTL and FTH). We previously showed that macrophages increase their expression of FTH1 when they are infected in vitro with Mycobacterium avium, without a significant increase in FTL. In this work, we investigated the role of macrophage FTH1 in M. avium infection in vivo. We found that mice deficient in FTH1 in myeloid cells are more resistant to M. avium infection, presenting lower bacterial loads and lower levels of proinflammatory cytokines than wild-type littermates, due to the lower levels of available iron in the tissues. Importantly, we also found that FTH1 produced by myeloid cells in response to infection may be found in circulation and that it plays a key role in iron redistribution. Specifically, in the absence of FTH1 in myeloid cells, increased expression of ferroportin is observed in liver granulomas and increased iron accumulation occurs in hepatocytes. These results highlight the importance of FTH1 expression in myeloid cells for iron redistribution during infection.


Asunto(s)
Circulación Sanguínea , Ferritinas/sangre , Hierro/metabolismo , Hígado/metabolismo , Infecciones por Mycobacterium/sangre , Células Mieloides/metabolismo , Animales , Proteínas de Transporte de Catión/metabolismo , Ferritinas/deficiencia , Regulación de la Expresión Génica , Inflamación/patología , Deficiencias de Hierro/sangre , Deficiencias de Hierro/metabolismo , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/metabolismo , Ratones , Infecciones por Mycobacterium/genética , Mycobacterium avium/crecimiento & desarrollo , Mycobacterium avium/fisiología
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