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1.
PLoS One ; 19(8): e0306255, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39121099

RESUMO

BACKGROUND: Iron (Fe) supplementation is a critical component of anemia therapy for patients with chronic kidney disease (CKD). However, serum Fe, ferritin, and transferrin saturation, used to guide Fe replacement, are far from optimal, as they can be influenced by malnutrition and inflammation. Currently, there is a trend of increasing Fe supplementation to target high ferritin levels, although the long-term risk has been overlooked. METHODS: We prospectively enrolled 28 patients with CKD on hemodialysis with high serum ferritin (> 1000 ng/ml) and tested the effects of 1-year deferoxamine treatment, accompanied by withdrawal of Fe administration, on laboratory parameters (Fe status, inflammatory and CKD-MBD markers), heart, liver, and iliac crest Fe deposition (quantitative magnetic resonance imaging [MRI]), and bone biopsy (histomorphometry and counting of the number of Fe positive cells in the bone marrow). RESULTS: MRI parameters showed that none of the patients had heart iron overload, but they all presented iron overload in the liver and bone marrow, which was confirmed by bone histology. After therapy, ferritin levels decreased, although neither hemoglobin levels nor erythropoietin dose was changed. A significant decrease in hepcidin and FGF-23 levels was observed. Fe accumulation was improved in the liver and bone marrow, reaching normal values only in the bone marrow. No significant changes in turnover, mineralization or volume were observed. CONCLUSIONS: Our data suggest that treatment with deferoxamine was safe and could improve Fe accumulation, as measured by MRI and histomorphometry. Whether MRI is considered a standard tool for investigating bone marrow Fe accumulation requires further investigation. Registry and the registration number of clinical trial: ReBEC (Registro Brasileiro de Ensaios Clinicos) under the identification RBR-3rnskcj available at: https://ensaiosclinicos.gov.br/pesquisador.


Assuntos
Medula Óssea , Desferroxamina , Ferritinas , Sobrecarga de Ferro , Ferro , Fígado , Diálise Renal , Humanos , Masculino , Feminino , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/metabolismo , Medula Óssea/metabolismo , Medula Óssea/efeitos dos fármacos , Medula Óssea/patologia , Ferritinas/sangue , Ferritinas/metabolismo , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/diagnóstico por imagem , Pessoa de Meia-Idade , Desferroxamina/uso terapêutico , Desferroxamina/administração & dosagem , Ferro/metabolismo , Idoso , Imageamento por Ressonância Magnética , Estudos Prospectivos , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/sangue , Fator de Crescimento de Fibroblastos 23 , Hepcidinas/metabolismo
2.
Eur J Clin Nutr ; 78(9): 801-807, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38909172

RESUMO

BACKGROUND/OBJECTIVES: Sickle cell anemia (SCA) is marked by hypoxia, inflammation, and secondary iron overload (IO), which potentially modulate hepcidin, the pivotal hormone governing iron homeostasis. The aim was to evaluate the iron incorporation in red blood cells (RBC) in SCA pediatric patients, considering the presence or absence of IO. SUBJECTS/METHODS: SCA children (n = 12; SCAtotal) ingested an oral stable iron isotope (57Fe) and iron incorporation in RBC was measured after 14 days. Patients with ≥1000 ng/mL serum ferritin were considered to present IO (SCAio+; n = 4) while the others were classified as being without IO (SCAio-; n = 8). Liver iron concentration (LIC) was determined by Magnetic Resonance Imaging (MRI) T2* method. RESULTS: The SCAio+ group had lower iron incorporation (mean ± SD: 0.166 ± 0.04 mg; 3.33 ± 0.757%) than SCAio- patients (0.746 ± 0.303 mg; 14.9 ± 6.05%) (p = 0.024). Hepcidin was not different between groups. Iron incorporation was inversely associated with serum ferritin level (SCAtotal group: r = -0.775, p = 0.041; SCAio- group: r = -0.982; p = 0.018) and sickle hemoglobin (HbS) presented positive correlation with iron incorporation (r = 0.991; p = 0.009) in SCAio- group. LIC was positively associated with ferritin (SCAtotal: r = 0.921; p = 0.026) and C reactive protein (SCAio+: r = 0.999; p = 0.020). CONCLUSION: SCAio+ group had lower iron incorporation in RBC than SCAio- group, suggesting that they may not need to reduce their intake of iron-rich food, as usually recommended. Conversely, a high percentage of HbS may indirectly exacerbate hypoxia and seems to increase iron incorporation in RBC. TRIAL REGISTRATION: This trial was registered at www.ensaiosclinicos.gov.br . Identifier RBR-4b7v8pt.


Assuntos
Anemia Falciforme , Eritrócitos , Ferritinas , Hepcidinas , Isótopos de Ferro , Sobrecarga de Ferro , Ferro , Humanos , Anemia Falciforme/sangue , Projetos Piloto , Eritrócitos/metabolismo , Criança , Masculino , Feminino , Ferritinas/sangue , Ferro/sangue , Ferro/metabolismo , Sobrecarga de Ferro/sangue , Adolescente , Hepcidinas/sangue , Fígado/metabolismo
3.
Eur J Nutr ; 63(6): 2163-2172, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38722385

RESUMO

PURPOSE: Iron absorption in sickle cell anemia (SCA) remains unclear and studies in adults with SCA are scarce. The aim of this study was to evaluate the iron absorption SCA adults and its association with iron status and hepcidin concentration. METHODS: SCA patients (n = 13; SCAtotal) and control participants (n = 10) ingested an oral stable iron isotope (57Fe). Iron absorption was measured by inductively coupled plasma mass spectrometry (ICP-MS) 14 days after isotope administration. Patients with ≥ 1000 ng/mL serum ferritin were considered to present iron overload (IO) (SCAio+; n = 3) and others classified without IO (SCAio-; n = 10). RESULTS: Iron absorption in the control group ranged from 0.3 to 26.5% (median = 0.9%), while it varied from 0.3 to 5.4% in SCAio+ (median = 0.5%) and from 0.3 to 64.2% in the SCAio- (median = 6.9%). Hepcidin median values were 14.1 ng/mL (3.0-31.9 ng/mL) in SCAio-, 6.2 ng/mL (3.3-7.8 ng/mL) in SCAio + and 6.2 ng/mL (0.6-9.3 ng/mL) in control. Iron absorption was associated with ferritin level (r = - 0.641; p = 0.018) and liver iron concentration (LIC; r = - 0.786; p = 0.036) in the SCAtotal group. CONCLUSION: Our data suggest that SCAio- individuals may be at risk of developing primary IO. Simultaneously, secondary IO may induce physiological adaptation, resulting in reduced iron absorption. Further studies evaluating intestinal iron absorption using larger sample sizes should be conducted to help establish a safe nutrition approach to be adopted and to ensure the security of food-fortifying public policies for these patients. TRIAL REGISTRATION: This trial was registered at www.ensaiosclinicos.gov.br (Identifier RBR-4b7v8pt).


Assuntos
Anemia Falciforme , Hepcidinas , Absorção Intestinal , Isótopos de Ferro , Humanos , Anemia Falciforme/sangue , Adulto , Masculino , Feminino , Isótopos de Ferro/farmacocinética , Hepcidinas/sangue , Adulto Jovem , Ferritinas/sangue , Ferro/sangue , Ferro/farmacocinética , Ferro/metabolismo , Sobrecarga de Ferro , Ferro da Dieta/farmacocinética , Ferro da Dieta/administração & dosagem , Pessoa de Meia-Idade , Estado Nutricional
4.
Trends Endocrinol Metab ; 35(6): 456-458, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38599900

RESUMO

Obesity is associated with dysfunctions in hypothalamic neurons that regulate metabolism, including agouti-related protein (AgRP)-expressing neurons. In a recent article, Zhang et al. demonstrated that either diet- or genetically induced obesity promoted iron accumulation specifically in AgRP neurons. Preventing iron overload in AgRP neurons mitigated diet-induced obesity and related comorbidities in male mice.


Assuntos
Proteína Relacionada com Agouti , Ferro , Obesidade , Obesidade/metabolismo , Animais , Humanos , Ferro/metabolismo , Proteína Relacionada com Agouti/metabolismo , Camundongos , Neurônios/metabolismo , Masculino , Hipotálamo/metabolismo , Sobrecarga de Ferro/metabolismo
5.
Redox Biol ; 71: 103074, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38367511

RESUMO

Brain iron accumulation constitutes a pathognomonic indicator in several neurodegenerative disorders. Metal accumulation associated with dopaminergic neuronal death has been documented in Parkinson's disease. Through the use of in vivo and in vitro models, we demonstrated that lipid dysregulation manifests as a neuronal and glial response during iron overload. In this study, we show that cholesterol content and triacylglycerol (TAG) hydrolysis were strongly elevated in mice midbrain. Lipid cacostasis was concomitant with the loss of dopaminergic neurons, astrogliosis and elevated expression of α-synuclein. Exacerbated lipid peroxidation and markers of ferroptosis were evident in the midbrain from mice challenged with iron overload. An imbalance in the activity of lipolytic and acylation enzymes was identified, favoring neutral lipid hydrolysis, and consequently reducing TAG and cholesteryl ester levels. Notably, these observed alterations were accompanied by motor impairment in iron-treated mice. In addition, neuronal and glial cultures along with their secretomes were used to gain further insight into the mechanism underlying TAG hydrolysis and cholesterol accumulation as cellular responses to iron accumulation. We demonstrated that TAG hydrolysis in neurons is triggered by astrocyte secretomes. Moreover, we found that the ferroptosis inhibitor, ferrostatin-1, effectively prevents cholesterol accumulation both in neurons and astrocytes. Taken together, these results indicate that lipid disturbances occur in iron-overloaded mice as a consequence of iron-induced oxidative stress and depend on neuron-glia crosstalk. Our findings suggest that developing therapies aimed at restoring lipid homeostasis may lead to specific treatment for neurodegeneration associated with ferroptosis and brain iron accumulation.


Assuntos
Ferroptose , Sobrecarga de Ferro , Transtornos Motores , Camundongos , Animais , Metabolismo dos Lipídeos , Transtornos Motores/metabolismo , Ferro/metabolismo , Peroxidação de Lipídeos , Neurônios Dopaminérgicos/metabolismo , Colesterol/metabolismo , Lipídeos
6.
Eur J Nutr ; 63(4): 1163-1175, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38358514

RESUMO

PURPOSE: The present study aimed at evaluating possible synergistic effects between two risk factors for cognitive decline and neurodegenerative disorders, i.e. iron overload and exposure to a hypercaloric/hyperlipidic diet, on cognition, insulin resistance, and hippocampal GLUT1, GLUT3, Insr mRNA expression, and AKT phosporylation. METHODS: Male Wistar rats were treated with iron (30 mg/kg carbonyl iron) or vehicle (5% sorbitol in water) from 12 to 14th post-natal days. Iron-treated rats received a standard laboratory diet or a high fat diet from weaning to adulthood (9 months of age). Recognition and emotional memory, peripheral blood glucose and insulin levels were evaluated. Glucose transporters (GLUT 1 and GLUT3) and insulin signaling were analyzed in the hippocampus of rats. RESULTS: Both iron overload and exposure to a high fat diet induced memory deficits. Remarkably, the association of iron with the high fat diet induced more severe cognitive deficits. Iron overload in the neonatal period induced higher insulin levels associated with significantly higher HOMA-IR, an index of insulin resistance. Long-term exposure to a high fat diet resulted in higher fasting glucose levels. Iron treatment induced changes in Insr and GLUT1 expression in the hippocampus. At the level of intracellular signaling, both iron treatment and the high fat diet decreased AKT phosphorylation. CONCLUSION: The combination of iron overload with exposure to a high fat diet only led to synergistic deleterious effect on emotional memory, while the effects induced by iron and by the high fat diet on AKT phosphorylation were comparable. These findings indicate that there is, at least to some extent, an additive effect of iron combined with the diet. Further studies investigating the mechanisms associated to deleterious effects on cognition and susceptibility for the development of age-associated neurodegenerative disorders are warranted.


Assuntos
Animais Recém-Nascidos , Dieta Hiperlipídica , Transportador de Glucose Tipo 1 , Hipocampo , Resistência à Insulina , Sobrecarga de Ferro , Transtornos da Memória , Ratos Wistar , Animais , Masculino , Dieta Hiperlipídica/efeitos adversos , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/metabolismo , Transtornos da Memória/etiologia , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Ratos , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 3/metabolismo , Transportador de Glucose Tipo 3/genética , Receptor de Insulina/metabolismo , Receptor de Insulina/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Glicemia/metabolismo , Insulina/sangue , Transdução de Sinais
7.
Rev Invest Clin ; 76(1): 18-28, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38262366

RESUMO

Background: Iron overload is frequent in patients with chronic liver disease, associated with shorter survival after liver transplantation in patients with hereditary hemochromatosis. Its effect on patients without hereditary hemochromatosis is unclear. The aim of the study was to study the clinical impact of iron overload in patients who underwent liver transplantation at an academic tertiary referral center. Methods: We performed a retrospective cohort study including all patients without hereditary hemochromatosis who underwent liver transplantation from 2015 to 2017 at an academic tertiary referral center in Mexico City. Explant liver biopsies were reprocessed to obtain the histochemical hepatic iron index, considering a score ≥ 0.15 as iron overload. Baseline characteristics were compared between patients with and without iron overload. Survival was estimated using the Kaplan-Meier method, compared with the log-rank test and the Cox proportional hazards model. Results: Of 105 patients included, 45% had iron overload. Viral and metabolic etiologies, alcohol consumption, and obesity were more frequent in patients with iron overload than in those without iron overload (43% vs. 21%, 32% vs. 22%, p = 0.011; 34% vs. 9%, p = 0.001; and 32% vs. 12%, p = 0.013, respectively). Eight patients died within 90 days after liver transplantation (one with iron overload). Complication rate was higher in patients with iron overload versus those without iron overload (223 vs. 93 events/100 personmonths; median time to any complication of 2 vs. 3 days, p = 0.043), without differences in complication type. Fatality rate was lower in patients with iron overload versus those without iron overload (0.7 vs. 4.5 deaths/100 person-months, p = 0.055). Conclusion: Detecting iron overload might identify patients at risk of early complications after liver transplantation. Further studies are required to understand the role of iron overload in survival.


Assuntos
Hemocromatose , Sobrecarga de Ferro , Hepatopatias , Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Hemocromatose/complicações , Hemocromatose/epidemiologia , Hemocromatose/patologia , Estudos Retrospectivos , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/complicações , Hepatopatias/complicações , Hepatopatias/metabolismo , Hepatopatias/patologia , Fígado/metabolismo
8.
Cell Chem Biol ; 31(2): 249-264.e7, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37944523

RESUMO

Iron overload, characterized by accumulation of iron in tissues, induces a multiorgan toxicity whose mechanisms are not fully understood. Using cultured cell lines, Caenorhabditis elegans, and mice, we found that ferroptosis occurs in the context of iron-overload-mediated damage. Exogenous oleic acid protected against iron-overload-toxicity in cell culture and Caenorhabditis elegans by suppressing ferroptosis. In mice, oleic acid protected against FAC-induced liver lipid peroxidation and damage. Oleic acid changed the cellular lipid composition, characterized by decreased levels of polyunsaturated fatty acyl phospholipids and decreased levels of ether-linked phospholipids. The protective effect of oleic acid in cells was attenuated by GW6471 (PPAR-α antagonist), as well as in Caenorhabditis elegans lacking the nuclear hormone receptor NHR-49 (a PPAR-α functional homologue). These results highlight ferroptosis as a driver of iron-overload-mediated damage, which is inhibited by oleic acid. This monounsaturated fatty acid represents a potential therapeutic approach to mitigating organ damage in iron overload individuals.


Assuntos
Ferroptose , Sobrecarga de Ferro , Animais , Camundongos , Caenorhabditis elegans , Ácido Oleico/farmacologia , Receptores Ativados por Proliferador de Peroxissomo , Sobrecarga de Ferro/tratamento farmacológico , Ferro , Éteres Fosfolipídicos
9.
Arch. argent. pediatr ; 121(4): e202202775, ago. 2023. ilus
Artigo em Inglês, Espanhol | LILACS, BINACIS | ID: biblio-1443050

RESUMO

La hemocromatosis es una enfermedad caracterizada por el excesivo depósito de hierro en múltiples órganos, entre ellos hígado, páncreas, piel y corazón. La infiltración de este último es un importante factor en morbilidad y mortalidad. Presentamos un caso de un paciente pediátrico con insuficiencia cardíaca terminal que ameritó trasplante cardíaco, que resultó sin complicaciones. Posterior a la cirugía, mostró mejoría bioquímica y clínica, lo que influyó positivamente en su calidad de vida y prolongó su supervivencia.


Hemochromatosis is a disease characterized by excess iron stores in multiple organs, including the liver, pancreas, skin, and heart. The infiltration of the heart is an important factor in morbidity and mortality. Here we describe the case of a pediatric patient with end-stage heart failure who required a heart transplantation, with no complications. After the surgery, she showed biochemical and clinical improvement, with a positive impact on her quality of life and a prolonged survival.


Assuntos
Humanos , Feminino , Criança , Transplante de Coração , Sobrecarga de Ferro/complicações , Hemocromatose/complicações , Hemocromatose/diagnóstico , Qualidade de Vida , Fígado
10.
Hematol., Transfus. Cell Ther. (Impr.) ; 45(supl.2): S11-S17, July 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1514201

RESUMO

ABSTRACT Introduction: During pregnancy, the iron requirement increases to meet the optimal growth of the fetus and prevent iron deficiency anemia-related complications in the mother. However, in sickle cell disease (SCD) primarily due to repeated blood transfusions and hemolysis-induced recycling of iron, its supplementation during pregnancy remains questionable and may be harmful. Methods: Twenty-five pregnant women with homozygous SCD and 25 pregnant women with normal hemoglobin variants were included as cases and control, respectively. Pregnancy and sickle cell anemia (SCA) were diagnosed using standard protocols. The serum iron, serum ferritin, total iron-binding capacity (TIBC), percentage transferrin saturation and C-reactive protein were estimated, as per the manufacturer's protocol. The complete blood count was performed. The unpaired 't-test' was performed using the SPSS v23.0 and the principal component analysis (PCA) was performed using the online software MetaboAnalyst for statistical analysis. Main Results: The studied cases had significantly lower mean hemoglobin and higher mean corpuscular volume (MCV), compared to controls. The mean serum-iron, serum-ferritin and percentage transferrin-saturation in the cases were significantly higher than that of the controls, while the TIBC was lower in the cases (p < 0.0001). The mean level of serum iron, ferritin, percentage transferrin saturation and TIBC were 309.44 ± 122.40mcg/dl, 860.36 ± 624.64ng/ml, 42.6 ± 17.30% and 241.32 ± 96.30 mcg/dl, respectively, in the cases and 95.36 ± 41.90mcg/dl, 122.28 ± 49.70ng/ml, 15.83 ± 3.10% and 492.6 ± 149.40mcg/dl in the controls, respectively. Higher MCV, mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) with lower hemoglobin (Hb) were noted in the cases. The PCA revealed that the cases were more heterogeneous in terms of the variability of the iron status and hematological indices than the controls. Conclusion: The current study shows iron sufficiency in most cases of pregnancy with SCA and suggests that evaluation of iron status must be made before initiating iron prophylaxis in pregnant women with SCA, especially in regions having a high prevalence of sickle cell hemoglobinopathy.


Assuntos
Humanos , Gravidez , Gravidez , Anemia Falciforme , Sobrecarga de Ferro , Fármacos Hematológicos
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