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result(s) for
"Iron Overload - blood"
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Iron Overload in Functional Hyperandrogenism: In a Randomized Trial, Bloodletting Does Not Improve Metabolic Outcomes
by
Ortiz-Flores, Andrés E
,
Martínez-García, María Ángeles
,
Fernández-Durán, Elena
in
Acetic acid
,
Adult
,
Antiandrogens
2021
Abstract
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.
Journal Article
Deferasirox effectively reduces iron overload in non-transfusion-dependent thalassemia (NTDT) patients: 1-year extension results from the THALASSA study
by
Ros, Jacqueline
,
Cappellini, M. Domenica
,
Kattamis, Antonis
in
Benzoates - therapeutic use
,
Blood Transfusion
,
Cross-Over Studies
2013
Patients with non-transfusion-dependent thalassemia (NTDT) often develop iron overload that requires chelation to levels below the threshold associated with complications. This can take several years in patients with high iron burden, highlighting the value of long-term chelation data. Here, we report the 1-year extension of the THALASSA trial assessing deferasirox in NTDT; patients continued with deferasirox or crossed from placebo to deferasirox. Of 133 patients entering extension, 130 completed. Liver iron concentration (LIC) continued to decrease with deferasirox over 2 years; mean change was −7.14 mg Fe/g dry weight (dw) (mean dose 9.8 ± 3.6 mg/kg/day). In patients originally randomized to placebo, whose LIC had increased by the end of the core study, LIC decreased in the extension with deferasirox with a mean change of −6.66 mg Fe/g dw (baseline to month 24; mean dose in extension 13.7 ± 4.6 mg/kg/day). Of 166 patients enrolled, 64 (38.6 %) and 24 (14.5 %) patients achieved LIC <5 and <3 mg Fe/g dw by the end of the study, respectively. Mean LIC reduction was greatest in patients with the highest pretreatment LIC. Deferasirox progressively decreases iron overload over 2 years in NTDT patients with both low and high LIC. Safety profile of deferasirox over 2 years was consistent with that in the core study.
Journal Article
Simultaneous Determination of Plasma Deferasirox and Deferasirox-Iron Complex Using an HPLC-UV System and Pharmacokinetics of Deferasirox in Patients With β-Thalassemia Major: Once-daily Versus Twice-daily Administration
by
Wu, Wen-Hsin
,
Kuo, Pei-Hsin
,
Wu, Tzu-Hua
in
Adult
,
Benzoates - administration & dosage
,
Benzoates - blood
2015
Deferasirox (DEFR), when administered BID, improves iron overload and decreases DEFR-related adverse effects in patients with β-thalassemia major. However, the pharmacokinetic (PK) disposition of DEFR and the iron–DEFR complex (Fe-[DEFR]2) in this dosing strategy is unclear.
Chromatographic analysis was performed using a solvent delivery system coupled to an HPLC-UV detector to determine the steady-state concentrations of DEFR (CDEFR) and Fe-(DEFR)2 (CFe-[DEFR]2) in β-thalassemia major patients (n = 8) following either once-daily or BID dosing, during which the PK parameters of the 2 dosing schedules were compared.
An HPLC-UV system for the analysis of blood samples following solid-phase extraction was validated. Patients who received 40 mg/kg of DEFR had higher mean CDEFR and CFe-[DEFR]2 values at all sampling times. However, concentrations of iron-DEFR complex were similar in patients who received 30 or 40 mg/kg of DEFR in the once-daily group at the 6- to 24-hour sampling times. There was no significant difference in any of the PK parameters; however, DEFR administration BID increased the mean trough levels of DEFR (183.8 [157.5] μmol/L) compared with once daily (87.7 [56.8] μmol/L), whereas all the patients had increased peak levels per individual DEFR dose when they were switched from once daily to BID (139.0 [59.8] μmol/L vs 289.2 [145.8] μmol/L, respectively).
Splitting the dose increased the peak levels of DEFR per unit dose in all patients and tends to increase drug exposures, but there were no significant differences in DEFR PK parameter estimates. Switching from once daily to BID may be considered for patients with an inadequate response to chelation therapy to achieve optimal drug levels. Further research is needed with a larger sample size to determine the clinical importance of the significant results due to the interindividual variability of DEFR.
Journal Article
Impact of non-transferrin-bound iron (NTBI) in comparison to serum ferritin on outcome after allogeneic stem cell transplantation (ASCT)
2017
The optimal parameters and time points for the measurement of iron overload (IO) in allogeneic stem cell transplantation (ASCT) patients are still under discussion. Hyperferritinemia and IO are poor prognostic factors in ASCT. We hypothesize that non-transferrin-bound iron (NBTI) is possibly a better marker to predict the effect of IO on the outcome than serum ferritin (SF), which however is not specific for IO. The aim of this prospective observational trial was to evaluate the influence of NBTI in comparison to SF on the outcome of ASCT patients [overall survival, bloodstream infections (BSIs), and invasive fungal infections (IFIs)]. We analyzed daily transferrin saturation (TSAT), SF, and NTBI (if TSAT exceeded 70%) in 100 patients who received ASCT during conditioning, and on day 0, +7, and +14 post-ASCT. After a median NTBI level of 0 μmol/l at baseline, the median of the area under the curve (AUC) of NTBI between conditioning and ASCT (d0) increased to 17 μmol*d/l, and between ASCT and day +14 to 56.3 μmol*d/l. Higher NTBI-AUC d0 resulted in a higher risk of BSI (HR 1.042,
p
= 0.009) and IFI (HR 1.070,
p
= 0.001) and showed a trend of inferior 1-year survival (65 vs. 76%,
p
= 0.09). Baseline SF did not influence BSI, but higher levels resulted in more IFI (HR 1.26,
p
< 0.001). In conclusion, NTBI possibly better predict for a higher risk of bloodstream infections than SF and needs further investigation.
Journal Article
Association between Serum Ferritin and Osteocalcin as a Potential Mechanism Explaining the Iron-Induced Insulin Resistance
by
Salas-Salvadó, Jordi
,
Cándido-Fernández, José
,
Arija-Val, Victoria
in
Adiponectin
,
Aged
,
Aged, 80 and over
2013
Increased iron stores are associated with increased risk of type 2 diabetes, however, the mechanisms underlying these associations are poorly understood. Because a reduction of circulating osteocalcin levels after iron overload have been demonstrated in cell cultures, and osteocalcin is related to glucose and insulin metabolism, the iron-induced osteocalcin reductions could contribute to explain the role of iron metabolism in the development of type 2 diabetes mellitus.
To analyzed the associations between serum total and uncarboxylated osteocalcin and adiponectin concentrations with serum ferritin and soluble transferrin receptor (sTfR) in elderly subjects.
We evaluated a total of 423 subjects from the PREDIMED cohort in a population-based cross-sectional analysis. Extensive clinical, nutritional and laboratory measurements, including total and uncarboxylated osteocalcin, adiponectin, ferritin and sTfR were recorded.
Serum ferritin was positively correlated with increased glucose and insulin circulating levels but also with HOMA-IR, and was inversely associated with total osteocalcin and adiponectin. A regression analysis revealed that serum ferritin and transferrin receptor levels were significantly associated with a decrease in total and uncarboxylated osteocalcin. Serum sTfR levels were associated with lower uncarboxylated osteocalcin levels in the whole-study subjects and remained significant only in the IFG (impaired fasting glucose) individuals.
We described, for the first time, an inverse association between serum ferritin and sTfR with osteocalcin and extend previous results on adiponectin, thus supporting that factors related to iron metabolism could contribute to the insulin resistance and the development of type 2 diabetes mellitus.
Controlled-Trials.com ISRCTN35739639 .
Journal Article
Impact of Inflammation on Ferritin, Hepcidin and the Management of Iron Deficiency Anemia in Chronic Kidney Disease
by
Ueda, Norishi
,
Takasawa, Kazuya
in
Anemia
,
Anemia, Iron-Deficiency - blood
,
Anemia, Iron-Deficiency - diagnosis
2018
Iron deficiency anemia (IDA) is a major problem in chronic kidney disease (CKD), causing increased mortality. Ferritin stores iron, representing iron status. Hepcidin binds to ferroportin, thereby inhibiting iron absorption/efflux. Inflammation in CKD increases ferritin and hepcidin independent of iron status, which reduce iron availability. While intravenous iron therapy (IIT) is superior to oral iron therapy (OIT) in CKD patients with inflammation, OIT is as effective as IIT in those without. Inflammation reduces predictive values of ferritin and hepcidin for iron status and responsiveness to iron therapy. Upper limit of ferritin to predict iron overload is higher in CKD patients with inflammation than in those without. However, magnetic resonance imaging studies show lower cutoff levels of serum ferritin to predict iron overload in dialysis patients with apparent inflammation than upper limit of ferritin proposed by international guidelines. Compared to CKD patients with inflammation, optimal ferritin levels for IDA are lower in those without, requiring reduced iron dose and leading to decreased mortality. The management of IDA should differ between CKD patients with and without inflammation and include minimization of inflammation. Further studies are needed to determine the impact of inflammation on ferritin, hepcidin and therapeutic strategy for IDA in CKD.
Journal Article
Management of Iron Overload in Beta-Thalassemia Patients: Clinical Practice Update Based on Case Series
2020
Thalassemia syndromes are characterized by the inability to produce normal hemoglobin. Ineffective erythropoiesis and red cell transfusions are sources of excess iron that the human organism is unable to remove. Iron that is not saturated by transferrin is a toxic agent that, in transfusion-dependent patients, leads to death from iron-induced cardiomyopathy in the second decade of life. The availability of effective iron chelators, advances in the understanding of the mechanism of iron toxicity and overloading, and the availability of noninvasive methods to monitor iron loading and unloading in the liver, heart, and pancreas have all significantly increased the survival of patients with thalassemia. Prolonged exposure to iron toxicity is involved in the development of endocrinopathy, osteoporosis, cirrhosis, renal failure, and malignant transformation. Now that survival has been dramatically improved, the challenge of iron chelation therapy is to prevent complications. The time has come to consider that the primary goal of chelation therapy is to avoid 24-h exposure to toxic iron and maintain body iron levels within the normal range, avoiding possible chelation-related damage. It is very important to minimize irreversible organ damage to prevent malignant transformation before complications set in and make patients ineligible for current and future curative therapies. In this clinical case-based review, we highlight particular aspects of the management of iron overload in patients with beta-thalassemia syndromes, focusing on our own experience in treating such patients. We review the pathophysiology of iron overload and the different ways to assess, quantify, and monitor it. We also discuss chelation strategies that can be used with currently available chelators, balancing the need to keep non-transferrin-bound iron levels to a minimum (zero) 24 h a day, 7 days a week and the risk of over-chelation.
Journal Article
COVID-19 as part of the hyperferritinemic syndromes: the role of iron depletion therapy
by
Bursi Roberto
,
Cafaro Giacomo
,
Gerli, Roberto
in
Antiphospholipid syndrome
,
Antiviral agents
,
Antiviral drugs
2020
SARS-CoV-2 infection is characterized by a protean clinical picture that can range from asymptomatic patients to life-threatening conditions. Severe COVID-19 patients often display a severe pulmonary involvement and develop neutrophilia, lymphopenia, and strikingly elevated levels of IL-6. There is an over-exuberant cytokine release with hyperferritinemia leading to the idea that COVID-19 is part of the hyperferritinemic syndrome spectrum. Indeed, very high levels of ferritin can occur in other diseases including hemophagocytic lymphohistiocytosis, macrophage activation syndrome, adult-onset Still’s disease, catastrophic antiphospholipid syndrome and septic shock. Numerous studies have demonstrated the immunomodulatory effects of ferritin and its association with mortality and sustained inflammatory process. High levels of free iron are harmful in tissues, especially through the redox damage that can lead to fibrosis. Iron chelation represents a pillar in the treatment of iron overload. In addition, it was proven to have an anti-viral and anti-fibrotic activity. Herein, we analyse the pathogenic role of ferritin and iron during SARS-CoV-2 infection and propose iron depletion therapy as a novel therapeutic approach in the COVID-19 pandemic.
Journal Article
Antioxidants Mediate Both Iron Homeostasis and Oxidative Stress
by
Imam, Mustapha
,
Ma, Jifei
,
Wang, Fudi
in
Anemia, Iron-Deficiency - blood
,
Anemia, Iron-Deficiency - drug therapy
,
Animals
2017
Oxidative stress is a common denominator in the pathogenesis of many chronic diseases. Therefore, antioxidants are often used to protect cells and tissues and reverse oxidative damage. It is well known that iron metabolism underlies the dynamic interplay between oxidative stress and antioxidants in many pathophysiological processes. Both iron deficiency and iron overload can affect redox state, and these conditions can be restored to physiological conditions using iron supplementation and iron chelation, respectively. Similarly, the addition of antioxidants to these treatment regimens has been suggested as a viable therapeutic approach for attenuating tissue damage induced by oxidative stress. Notably, many bioactive plant-derived compounds have been shown to regulate both iron metabolism and redox state, possibly through interactive mechanisms. This review summarizes our current understanding of these mechanisms and discusses compelling preclinical evidence that bioactive plant-derived compounds can be both safe and effective for managing both iron deficiency and iron overload conditions.
Journal Article
A genome-wide meta-analysis yields 46 new loci associating with biomarkers of iron homeostasis
2021
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.Bell et al. report 46 new loci associated with biomarkers of iron homeostasis, including ferritin levels, iron binding capacity, and iron saturation, in the Icelandic, Danish and UK populations. The associated loci point to new iron-regulating proteins and important genetic differences between men and women.
Journal Article