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1.
Swiss Med Wkly ; 154: 3635, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38579297

RESUMO

BACKGROUND: Iron deficiency without anaemia is a common health problem, especially in young menstruating women. The efficacy of the usually recommended oral iron supplementation is limited due to increased plasma hepcidin concentration, which reduces iron absorption and leads to side effects such as intestinal irritation. This observation raises the question of how low-dose iron therapy may affect plasma hepcidin levels and whether oral iron intake dose-dependently affects plasma hepcidin production. METHODS: Fifteen non-anaemic women with iron deficiency (serum ferritin ≤30 ng/ml) received a single dose of 0, 6, 30, or 60 mg of elemental oral iron as ferrous sulfate on different days. Plasma hepcidin was measured before and seven hours after each dose. RESULTS: Subjects had an average age of 23 (standard deviation = 3.0) years and serum ferritin of 24 ng/ml (interquartile range = 16-27). The highest mean change in plasma hepcidin levels was measured after ingesting 60 mg of iron, increasing from 2.1 ng/ml (interquartile range = 1.6-2.9) to 4.1 ng/ml (interquartile range = 2.5-6.9; p < 0.001). Iron had a significant dose-dependent effect on the absolute change in plasma hepcidin (p = 0.008), where lower iron dose supplementation resulted in lower plasma hepcidin levels. Serum ferritin levels were significantly correlated with fasting plasma hepcidin levels (R2 = 0.504, p = 0.003) and the change in plasma hepcidin concentration after iron intake (R2 = 0.529, p = 0.002). CONCLUSION: We found a dose-dependent effect of iron supplementation on plasma hepcidin levels. Lower iron dosage results in a smaller increase in hepcidin and might thus lead to more efficient intestinal iron absorption and fewer side effects. The effectiveness and side effects of low-dose iron treatment in women with iron deficiency should be further investigated. This study was registered at the Swiss National Clinical Trials Portal (2021-00312) and ClinicalTrials.gov (NCT04735848).


Assuntos
Hepcidinas , Ferro , Feminino , Humanos , Anemia Ferropriva/tratamento farmacológico , Suplementos Nutricionais , Ferritinas , Hepcidinas/efeitos dos fármacos , Hepcidinas/metabolismo , Ferro/farmacologia , Ferro/uso terapêutico , Deficiências de Ferro/tratamento farmacológico , Estado Nutricional
3.
Swiss Med Wkly ; 153: 40079, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37229775

RESUMO

BACKGROUND: Iron deficiency without anaemia is highly prevalent and is particularly associated with fatigue, cognitive impairment, or poor physical endurance. Standard oral iron therapy often results in intestinal irritation with associated side effects and premature discontinuation of therapy, therefore, optimal oral iron therapy with sufficient iron absorption and minimal side effects is desirable. METHODS: Thirty-six iron-deficient non-anaemic premenopausal women (serum ferritin ≤30 ng/ml, haemoglobin ≥117 g/l) with normal body mass index (BMI) and no hypermenorrhea received 6 mg of elemental oral iron (corresponding to 18.6 mg ferrous sulphate) twice daily for 8 weeks. RESULTS: Participants treated with low-dose iron had an average age of 28 years and a BMI of 21 kg/m2. Their serum ferritin and haemoglobin increased significantly from 18 ng/ml to 33 ng/ml (p <0.001) and from 135 g/l to 138 g/l (p = 0.014), respectively. Systolic blood pressure increased from 114 mmHg to 120 mmHg (p = 0.003). Self-reported health status improved after 8 weeks (p <0.001) and only one woman reported gastrointestinal side effects (3%). CONCLUSION: This prospective open-label single-arm trial shows that oral iron treatment of 6 mg of elemental iron twice daily over 8 weeks is effective in iron-deficient non-anaemic women. Due to the negligible side effects, low-dose iron treatment is a valuable therapeutic option for iron-deficient non-anaemic women with normal BMI and menstruation. Further placebo-controlled studies with a larger number of participants are needed to confirm these results. CLINICALTRIALS: gov NCT04636060.


Assuntos
Anemia Ferropriva , Ferro , Adulto , Feminino , Humanos , Anemia Ferropriva/tratamento farmacológico , Ferritinas , Hemoglobinas/análise , Estudos Prospectivos
6.
Eur J Appl Physiol ; 122(12): 2683-2694, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36129579

RESUMO

PURPOSE: Menstrual cycle phase affects resting hepcidin levels, but such effects on the hepcidin response to exercise are still unclear. Thus, we investigated the hepcidin response to running during three different menstrual cycle phases. METHODS: Twenty-one endurance-trained eumenorrheic women performed three identical interval running protocols during the early-follicular phase (EFP), late-follicular phase (LFP), and mid-luteal phase (MLP). The protocol consisted of 8 × 3 min bouts at 85% of the maximal aerobic speed, with 90-s recovery. Blood samples were collected pre-exercise and at 0 h, 3 h and 24 h post-exercise. RESULTS: Data presented as mean ± SD. Ferritin were lower in the EFP than the LFP (34.82 ± 16.44 vs 40.90 ± 23.91 ng/ml, p = 0.003), while iron and transferrin saturation were lower during the EFP (58.04 ± 19.70 µg/dl, 14.71 ± 5.47%) compared to the LFP (88.67 ± 36.38 µg/dl, 22.22 ± 9.54%; p < 0.001) and the MLP (80.20 ± 42.05 µg/dl, 19.87 ± 10.37%; p = 0.024 and p = 0.045, respectively). Hepcidin was not affected by menstrual cycle (p = 0.052) or menstrual cycle*time interaction (p = 0.075). However, when comparing hepcidin at 3 h post-exercise, a moderate and meaningful effect size showed that hepcidin was higher in the LFP compared to the EFP (3.01 ± 4.16 vs 1.26 ± 1.25 nMol/l; d = 0.57, CI = 0.07-1.08). No effect of time on hepcidin during the EFP was found either (p = 0.426). CONCLUSION: The decrease in iron, ferritin and TSAT levels during the EFP may mislead the determination of iron status in eumenorrheic athletes. However, although the hepcidin response to exercise appears to be reduced in the EFP, it shows no clear differences between the phases of the menstrual cycle (clinicaltrials.gov: NCT04458662).


Assuntos
Hepcidinas , Corrida , Feminino , Humanos , Ciclo Menstrual/fisiologia , Ferritinas , Ferro , Homeostase
7.
BMJ Open ; 12(3): e056316, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264362

RESUMO

BACKGROUND: Frequent whole blood donors have an increased risk of developing iron deficiency. Iron deficiency can have detrimental health effects when left untreated. Donation intervals are commonly too short to replenish iron stores and extending these reduces donor availability. Oral iron supplementation is known to shorten iron store recovery time but may also induce gastrointestinal complaints. We aim to optimise the effectiveness of iron supplements while minimising the risks of side effects. Therefore, we will evaluate the impact of different iron supplementation protocols in terms of dosage and frequency on ferritin and haemoglobin levels, gastrointestinal side effects, iron deficiency-related symptoms and donor return compared with placebo supplementation. METHODS: Twelve hundred whole blood donors with ferritin levels ≤30 µg/L are included into a double-blind, randomised controlled trial. Participants are randomly allocated to one of six arms, administering capsules containing 0 mg, 30 mg or 60 mg of iron, either on alternate days or daily for 56 days. At baseline and 56, 122 and 182 days of follow-up, ferritin and haemoglobin levels are measured, and compliance, donor return, dietary iron intake, gastrointestinal, iron deficiency-related symptoms and general health are assessed by questionnaire. ETHICS AND DISSEMINATION: This study will provide a comprehensive overview of the effects of different frequencies and dosages of administration of iron supplements on iron status and health effects, thereby considering individual differences in treatment adherence and lifestyle. The outcome will provide scientific evidence to guide the debate if and how oral iron supplements may support the recovery of whole blood donors with low ferritin levels. TRIAL REGISTRATION NUMBER: NL8590; The Dutch trial registry.


Assuntos
Anemia Ferropriva , Deficiências de Ferro , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/prevenção & controle , Doadores de Sangue , Suplementos Nutricionais , Ferritinas , Hemoglobinas/análise , Humanos , Ferro , Ferro da Dieta , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Int J Mol Sci ; 23(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35163840

RESUMO

Pathogenic TMPRSS6 variants impairing matriptase-2 function result in inappropriately high hepcidin levels relative to body iron status, leading to iron refractory iron deficiency anemia (IRIDA). As diagnosing IRIDA can be challenging due to its genotypical and phenotypical heterogeneity, we assessed the transferrin saturation (TSAT)/hepcidin ratio to distinguish IRIDA from multi-causal iron deficiency anemia (IDA). We included 20 IRIDA patients from a registry for rare inherited iron disorders and then enrolled 39 controls with IDA due to other causes. Plasma hepcidin-25 levels were measured by standardized isotope dilution mass spectrometry. IDA controls had not received iron therapy in the last 3 months and C-reactive protein levels were <10.0 mg/L. IRIDA patients had significantly lower TSAT/hepcidin ratios compared to IDA controls, median 0.6%/nM (interquartile range, IQR, 0.4-1.1%/nM) and 16.7%/nM (IQR, 12.0-24.0%/nM), respectively. The area under the curve for the TSAT/hepcidin ratio was 1.000 with 100% sensitivity and specificity (95% confidence intervals 84-100% and 91-100%, respectively) at an optimal cut-off point of 5.6%/nM. The TSAT/hepcidin ratio shows excellent performance in discriminating IRIDA from TMPRSS6-unrelated IDA early in the diagnostic work-up of IDA provided that recent iron therapy and moderate-to-severe inflammation are absent. These observations warrant further exploration in a broader IDA population.


Assuntos
Anemia Ferropriva/sangue , Hepcidinas/sangue , Proteínas de Membrana/genética , Serina Endopeptidases/genética , Transferrina/metabolismo , Adolescente , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/genética , Área Sob a Curva , Proteína C-Reativa/metabolismo , Criança , Humanos , Masculino , Sensibilidade e Especificidade , Adulto Jovem
9.
Sci Rep ; 12(1): 1199, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-35075227

RESUMO

Kidney iron deposition may play a role in the progression of tubulointerstitial injury during chronic kidney disease. Here, we studied the molecular mechanisms of kidney iron loading in experimental focal segmental glomerulosclerosis (FSGS) and investigated the effect of iron-reducing interventions on disease progression. Thy-1.1 mice were injected with anti-Thy-1.1 monoclonal antibody (mAb) to induce proteinuria. Urine, blood and tissue were collected at day (D)1, D5, D8, D15 and D22 after mAb injection. Thy-1.1 mice were subjected to captopril (CA), iron-deficient (ID) diet or iron chelation (deferoxamine; DFO). MAb injection resulted in significant albuminuria at all time points (p < 0.01). Kidney iron loading, predominantly in distal tubules, increased in time, along with urinary kidney injury molecule-1 and 24p3 concentration, as well as kidney mRNA expression of Interleukin-6 (Il-6) and Heme oxygenase-1 (Ho-1). Treatment with CA, ID diet or DFO significantly reduced kidney iron deposition at D8 and D22 (p < 0.001) and fibrosis at D22 (p < 0.05), but not kidney Il-6. ID treatment increased kidney Ho-1 (p < 0.001). In conclusion, kidney iron accumulation coincides with progression of tubulointerstitial injury in this model of FSGS. Reduction of iron loading halts disease progression. However, targeted approaches to prevent excessive kidney iron loading are warranted to maintain the delicate systemic and cellular iron balance.


Assuntos
Glomerulosclerose Segmentar e Focal/metabolismo , Ferro/metabolismo , Túbulos Renais Distais/metabolismo , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Captopril/uso terapêutico , Desferroxamina/uso terapêutico , Modelos Animais de Doenças , Feminino , Glomerulosclerose Segmentar e Focal/dietoterapia , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Masculino , Camundongos , Receptores de Superfície Celular/metabolismo , Sideróforos/uso terapêutico
10.
Front Cell Infect Microbiol ; 11: 740704, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778104

RESUMO

Objective: The opportunistic pathogen Streptococcus gallolyticus is one of the few intestinal bacteria that has been consistently linked to colorectal cancer (CRC). This study aimed to identify novel S. gallolyticus-induced pathways in colon epithelial cells that could further explain how S. gallolyticus contributes to CRC development. Design and Results: Transcription profiling of in vitro cultured CRC cells that were exposed to S. gallolyticus revealed the specific induction of oxidoreductase pathways. Most prominently, CYP1A and ALDH1 genes that encode phase I biotransformation enzymes were responsible for the detoxification or bio-activation of toxic compounds. A common feature is that these enzymes are induced through the Aryl hydrocarbon receptor (AhR). Using the specific inhibitor CH223191, we showed that the induction of CYP1A was dependent on the AhR both in vitro using multiple CRC cell lines as in vivo using wild-type C57bl6 mice colonized with S. gallolyticus. Furthermore, we showed that CYP1 could also be induced by other intestinal bacteria and that a yet unidentified diffusible factor from the S. galloltyicus secretome (SGS) induces CYP1A enzyme activity in an AhR-dependent manner. Importantly, priming CRC cells with SGS increased the DNA damaging effect of the polycyclic aromatic hydrocarbon 3-methylcholanthrene. Conclusion: This study shows that gut bacteria have the potential to modulate the expression of biotransformation pathways in colonic epithelial cells in an AhR-dependent manner. This offers a novel theory on the contribution of intestinal bacteria to the etiology of CRC by modifying the capacity of intestinal epithelial or (pre-)cancerous cells to (de)toxify dietary components, which could alter intestinal susceptibility to DNA damaging events.


Assuntos
Neoplasias Colorretais , Streptococcus gallolyticus , Animais , Biotransformação , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Células Epiteliais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Streptococcus gallolyticus/metabolismo
11.
Curr Opin Hematol ; 28(6): 438-444, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34494977

RESUMO

PURPOSE OF REVIEW: Red blood cell (RBC) clearance has been studied for decades in many different pathologies, which has revealed different routes of RBC degradation, depending on the situation. This review summarizes the latest mechanistic insights on RBC clearance in different contexts; during homeostatic removal, immune-mediated destruction, and systemic inflammation. RECENT FINDINGS: Besides the recognition of a variety of potential 'eat me' signals on RBCs, recent evidence suggests that normal RBC degradation is driven by the increase of the adhesive properties of RBCs, mediating the retention in the spleen and leading to RBC hemolysis. Furthermore, immune-mediated degradation of RBCs seems to be fine-tuned by the balance between the density of the antigens expressed on RBCs and the presence of 'don't eat me' signals. Moreover, besides RBC clearance by macrophages, neutrophils seem to play a much more prominent role in immune-mediated RBC removal than anticipated. Lastly, RBC clearance during systemic inflammation appears to be driven by a combination of extreme macrophage activity in response to proinflammatory cytokines as well as direct damage of RBC by the inflammation or inflammatory agent. SUMMARY: Recent studies on RBC clearance have expanded our knowledge on their destruction in different contexts.


Assuntos
Eritrócitos , Eritrócitos/citologia , Hemólise , Humanos , Inflamação/sangue , Macrófagos/citologia , Neutrófilos/citologia
12.
Blood Rev ; 50: 100866, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34284901

RESUMO

Iron is indispensable for human life. However, it is also potentially toxic, since it catalyzes the formation of harmful oxidative radicals in unbound form and may facilitate pathogen growth. Therefore, iron homeostasis needs to be tightly regulated. Rapid growth and development require large amounts of iron, while (especially young) children are vulnerable to infections with iron-dependent pathogens due to an immature immune system. Moreover, unbalanced iron status early in life may have effects on the nervous system, immune system and gut microbiota that persist into adulthood. In this narrative review, we assess the critical roles of iron for growth and development and elaborate how the body adapts to physiologically high iron demands during the journey from fetus to adolescent. As a first step towards the development of clinical guidelines for the management of iron disorders in children, we summarize the unmet needs regarding the developmental aspects of iron homeostasis.


Assuntos
Feto , Ferro , Adolescente , Adulto , Criança , Homeostase , Humanos
13.
Am J Physiol Gastrointest Liver Physiol ; 320(6): G1105-G1110, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33949198

RESUMO

Phlebotomies are performed in hereditary hemochromatosis (HH) to maintain normal iron concentrations. Proton-pump inhibitors (PPIs) can reduce the number of phlebotomies in patients with HH. However, in patients without HH, the iron concentrations do not appear to be compromised when using PPIs. Therefore, we aim to explain the differences in iron absorption between patients with and without HH. In 10 p.cysteine282tyrosine (p.C282Y) homozygous HH patients with normalized iron stores and 10 healthy control subjects (HCs), the iron parameters and hepcidin concentrations were determined before ingestion of a pharmacological dose of 50 mg iron [ferric iron (Fe3+)] polymaltose and hourly for 4 h afterward. This was repeated after 7 days of treatment with pantoprazole 40 mg once daily. Serum iron concentrations and transferrin saturation percentages dropped significantly during PPI use in the patients with HH, whereas no changes were observed in the HCs. Hepcidin concentrations were lower in the patients with HH compared with the HCs both before and during PPI use. In both groups, hepcidin levels did not significantly decrease during the treatment. Seven-day PPI use significantly reduces iron absorption in patients with HH but not in HCs. Changes in hepcidin concentrations could not explain these different PPI effects on iron absorption probably due to a small sample size.NEW & NOTEWORTHY This study confirms that lowering gastric acidity by proton pump inhibitors results in a reduction in iron absorption in patients with hemochromatosis and not in healthy control subjects. The presupposition that a decrease in hepcidin concentration in healthy control subjects in response to lowering gastric acidity can explain the difference in iron absorption between these groups could not be confirmed probably because of a small sample size.


Assuntos
Ferritinas/sangue , Hemocromatose/sangue , Hepcidinas/sangue , Ferro/sangue , Adulto , Índice de Massa Corporal , Feminino , Hemocromatose/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Pantoprazol/uso terapêutico , Inibidores da Bomba de Prótons/uso terapêutico
14.
Blood ; 138(15): 1293-1303, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33876222

RESUMO

Anemia of inflammation is a hallmark of tuberculosis. Factors controlling iron metabolism during anemia of inflammation and its resolution are uncertain. Whether iron supplements should be given during antituberculosis treatment to support hemoglobin (Hb) recovery is unclear. Before and during treatment of tuberculosis, we assessed iron kinetics, as well as changes in inflammation and iron metabolism indices. In a 26-week prospective study, Tanzanian adults with tuberculosis (N = 18) were studied before treatment and then every 2 weeks during treatment; oral and intravenous iron tracers were administered before treatment and after intensive phase (8/12 weeks) and complete treatment (24 weeks). No iron supplements were given. Before treatment, hepcidin and erythroferrone (ERFE) were greatly elevated, erythrocyte iron utilization was high (∼80%), and iron absorption was negligible (<1%). During treatment, hepcidin and interleukin-6 levels decreased ∼70% after only 2 weeks (P< .001); in contrast, ERFE did not significantly decrease until 8 weeks (P< .05). ERFE and interleukin-6 were the main opposing determinants of hepcidin (P< .05), and greater ERFE was associated with reticulocytosis and Hb repletion (P< .01). Dilution of baseline tracer concentration was 2.6-fold higher during intensive phase treatment (P< .01), indicating enhanced erythropoiesis. After treatment completion, iron absorption increased ∼20-fold (P< .001), and Hb increased ∼25% (P< .001). In tuberculosis-associated anemia of inflammation, our findings suggest that elevated ERFE is unable to suppress hepcidin, and iron absorption is negligible. During treatment, as inflammation resolves, ERFE may remain elevated, contributing to hepcidin suppression and Hb repletion. Iron is well absorbed only after tuberculosis treatment, and supplementation should be reserved for patients remaining anemic after treatment. This trial was registered at www.clinicaltrials.gov as #NCT02176772.


Assuntos
Anemia/metabolismo , Inflamação/metabolismo , Ferro/metabolismo , Tuberculose/metabolismo , Adulto , Anemia/complicações , Gerenciamento Clínico , Feminino , Hepcidinas/metabolismo , Homeostase , Humanos , Inflamação/complicações , Masculino , Hormônios Peptídicos/metabolismo , Estudos Prospectivos , Tuberculose/complicações , Tuberculose/terapia , Adulto Jovem
15.
Kidney Int ; 99(6): 1280-1295, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33839163

RESUMO

In chronic kidney disease, anemia and disordered iron homeostasis are prevalent and associated with significant adverse consequences. In 2012, Kidney Disease: Improving Global Outcomes (KDIGO) issued an anemia guideline for managing the diagnosis, evaluation, and treatment of anemia in chronic kidney disease. Since then, new data have accrued from basic research, epidemiological studies, and randomized trials that warrant a re-examination of previous recommendations. Therefore, in 2019, KDIGO decided to convene 2 Controversies Conferences to review the latest evidence, explore new and ongoing controversies, assess change implications for the current KDIGO anemia guideline, and propose a research agenda. The first conference, described here, focused mainly on iron-related issues, including the contribution of disordered iron homeostasis to the anemia of chronic kidney disease, diagnostic challenges, available and emerging iron therapies, treatment targets, and patient outcomes. The second conference will discuss issues more specifically related to erythropoiesis-stimulating agents, including epoetins, and hypoxia-inducible factor-prolyl hydroxylase inhibitors. Here we provide a concise overview of the consensus points and controversies resulting from the first conference and prioritize key questions that need to be answered by future research.


Assuntos
Anemia , Hematínicos , Inibidores de Prolil-Hidrolase , Insuficiência Renal Crônica , Anemia/diagnóstico , Anemia/epidemiologia , Anemia/etiologia , Hematínicos/uso terapêutico , Humanos , Ferro , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/terapia
17.
Scand J Med Sci Sports ; 31(3): 643-652, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33249618

RESUMO

The use of oral contraceptives (OCs) by female athletes may lead to improved iron status, possibly through the regulation of hepcidin by sex hormones. The present work investigates the response of hepcidin and interleukin-6 (IL-6) to an interval exercise in both phases of the OC cycle. Sixteen endurance-trained OC users (age 25.3 ± 4.7 years; height 162.4 ± 5.7 cm; body mass 56.0 ± 5.7 kg; body fat percentage 24.8 ± 6.0%; peak oxygen consumption [VO2peak ]: 47.4 ± 5.5 mL min-1 kg-1 ) followed an identical interval running protocol during the withdrawal and active pill phases of the OC cycle. This protocol consisted of 8 × 3 minutes bouts at 85% VO2peak speed with 90 seconds recovery intervals. Blood samples were collected pre-exercise, and at 0 hour, 3 hours, and 24 hours post-exercise. Pre-exercise 17ß-estradiol was lower (P = .001) during the active pill than the withdrawal phase (7.91 ± 1.81 vs 29.36 ± 6.45 pg/mL [mean ± SEM]). No differences were seen between the OC phases with respect to hepcidin or IL-6 concentrations, whether taking all time points together or separately. However, within the withdrawal phase, hepcidin concentrations were higher at 3 hours post-exercise (3.33 ± 0.95 nmol/L) than at pre-exercise (1.04 ± 0.20 nmol/L; P = .005) and 0 hour post-exercise (1.41 ± 0.38 nmol/L; P = .045). Within both OC phases, IL-6 was higher at 0 hour post-exercise than at any other time point (P < .05). Similar trends in hepcidin and IL-6 concentrations were seen at the different time points during both OC phases. OC use led to low 17ß-estradiol concentrations during the active pill phase but did not affect hepcidin. This does not, however, rule out estradiol affecting hepcidin levels.


Assuntos
Anticoncepcionais Orais Hormonais/administração & dosagem , Treino Aeróbico/métodos , Hepcidinas/sangue , Interleucina-6/sangue , Corrida/fisiologia , Adulto , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Progesterona/sangue , Prolactina/sangue , Tireotropina/sangue , Adulto Jovem
18.
Lancet ; 397(10270): 233-248, 2021 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-33285139

RESUMO

Iron deficiency is one of the leading contributors to the global burden of disease, and particularly affects children, premenopausal women, and people in low-income and middle-income countries. Anaemia is one of many consequences of iron deficiency, and clinical and functional impairments can occur in the absence of anaemia. Iron deprivation from erythroblasts and other tissues occurs when total body stores of iron are low or when inflammation causes withholding of iron from the plasma, particularly through the action of hepcidin, the main regulator of systemic iron homoeostasis. Oral iron therapy is the first line of treatment in most cases. Hepcidin upregulation by oral iron supplementation limits the absorption efficiency of high-dose oral iron supplementation, and of oral iron during inflammation. Modern parenteral iron formulations have substantially altered iron treatment and enable rapid, safe total-dose iron replacement. An underlying cause should be sought in all patients presenting with iron deficiency: screening for coeliac disease should be considered routinely, and endoscopic investigation to exclude bleeding gastrointestinal lesions is warranted in men and postmenopausal women presenting with iron deficiency anaemia. Iron supplementation programmes in low-income countries comprise part of the solution to meeting WHO Global Nutrition Targets.


Assuntos
Anemia Ferropriva , Saúde Global , Ferro , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/etiologia , Anti-Infecciosos , Suplementos Nutricionais , Hepcidinas , Humanos , Ferro/administração & dosagem , Deficiências de Ferro
19.
Nutrients ; 12(12)2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348847

RESUMO

Menopause commonly presents the gradual accumulation of iron in the body over the years, which is a risk factor for diseases such as cancer, osteoporosis, or cardiovascular diseases. Running exercise is known to acutely increase hepcidin levels, which reduces iron absorption and recycling. As this fact has not been studied in postmenopausal women, this study investigated the hepcidin response to running exercise in this population. Thirteen endurance-trained postmenopausal women (age: 51.5 ± 3.89 years; height: 161.8 ± 4.9 cm; body mass: 55.9 ± 3.6 kg; body fat: 24.7 ± 4.2%; peak oxygen consumption: 42.4 ± 4.0 mL·min-1·kg-1) performed a high-intensity interval running protocol, which consisted of 8 × 3 min bouts at 85% of the maximal aerobic speed with 90-second recovery. Blood samples were collected pre-exercise, 0, 3, and 24 hours post-exercise. As expected, hepcidin exhibited higher values at 3 hours post-exercise (3.69 ± 3.38 nmol/L), but also at 24 hours post-exercise (3.25 ± 3.61 nmol/L), in comparison with pre-exercise (1.77 ± 1.74 nmol/L; p = 0.023 and p = 0.020, respectively) and 0 hour post-exercise (2.05 ± 2.00 nmol/L; p = 0.021 and p = 0.032, respectively) concentrations. These differences were preceded by a significant increment of interleukin-6 at 0 hour post-exercise (3.41 ± 1.60 pg/mL) compared to pre-exercise (1.65 ± 0.48 pg/m, p = 0.003), 3 hours (1.50 ± 0.00 pg/mL, p = 0.002) and 24 hours post-exercise (1.52 ± 0.07 pg/mL, p = 0.001). Hepcidin peaked at 3 hours post-exercise as the literature described for premenopausal women but does not seem to be fully recovered to pre-exercise levels within 24 hours post-exercise, as it would be expected. This suggests a slower recovery of basal hepcidin levels in postmenopausal women, suggesting interesting applications in order to modify iron homeostasis as appropriate, such as the prevention of iron accumulation or proper timing of iron supplementation.


Assuntos
Atletas/estatística & dados numéricos , Treino Aeróbico/métodos , Hepcidinas/sangue , Menopausa/sangue , Resistência Física/fisiologia , Corrida/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade
20.
PLoS One ; 15(2): e0218694, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32107492

RESUMO

INTRODUCTION: Iron deficiency is a treatable cause of severe anaemia in low-and-middle-income-countries (LMIC). Diagnosing it remains challenging as peripheral blood markers poorly reflect bone-marrow iron deficiency (BM-ID), especially in the context of HIV-infection. METHODS: Severely anaemic (haemoglobin ≤70g/l) HIV-infected adults were recruited at Queen Elizabeth Central Hospital, Blantyre, Malawi. BM-ID was evaluated. Accuracy of blood markers (including hepcidin, mean corpuscular volume, mean cellular haemoglobin concentration, serum iron, serum ferritin, soluble transferrin receptor (sTfR), sTfR index, sTfR-ratio) to detect BM-ID was evaluated by ROC area under the curve (AUCROC). RESULTS: Seventy-three patients were enrolled and 35 (48.0%) had BM-ID. Although hepcidin and MCV performed best (AUCROC of 0.593 and 0.545 respectively) all markers performed poorly in identifying BM-ID (ROC<0.6). The AUCROC of hepcidin in males was 0.767 (sensitivity 80%, specificity 78%) and in women 0.490 (sensitivity 60%, specificity 61%). CONCLUSION: BM-ID deficiency was common in severely anaemic HIV-infected patients. It is an important and potential treatable contributor to severe anaemia but lack of definitive biomarkers makes it difficult to accurately assess iron status in these patients. Further investigation of the potential of hepcidin is needed, including exploration of the differences in hepcidin results between males and females.


Assuntos
Anemia Ferropriva/diagnóstico , Infecções por HIV/complicações , Hepcidinas/sangue , Adulto , Anemia Ferropriva/sangue , Anemia Ferropriva/complicações , Biomarcadores/sangue , Células da Medula Óssea/metabolismo , Feminino , Ferritinas/sangue , Humanos , Ferro/sangue , Malaui , Masculino , Receptores da Transferrina/sangue , Sensibilidade e Especificidade
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