Sex similarities and divergences in systemic and muscle iron metabolism adaptations to extreme physical inactivity in rats.

Background: Previous data in humans suggest that extreme physical inactivity (EPI) affects iron metabolism differently between sexes. Our objective was to deepen the underlying mechanisms by studying rats of both sexes exposed to hindlimb unloading (HU), the reference experimental model mimicking EPI.

Methods: Eight-week-old male and female Wistar rats were assigned to control (CTL) or hindlimb unloading (HU) conditions (n = 12/group).

Dry immersion rapidly disturbs iron metabolism in men and women: results from the VIVALDI studies.

Iron is essential for cell respiration, muscle metabolism, and oxygen transport. Recent research has shown that simulated microgravity rapidly affects iron metabolism in men. However, its impact on women remains unclear.

Differences in bone microarchitecture between genetic and secondary iron-overload mouse models suggest a role for hepcidin deficiency in iron-related osteoporosis.

Unlabelled: Iron overload is one of the secondary osteoporosis etiologies. Cellular and molecular mechanisms involved in iron-related osteoporosis are not fully understood.

Aim: The aim of the study was to investigate the respective roles of iron excess and hepcidin, the systemic iron regulator, in the development of iron-related osteoporosis.

Iron metabolism regulation in females and males exposed to simulated microgravity: results from the randomized trial Artificial Gravity Bed Rest-European Space Agency (AGBRESA).

Background: Iron metabolism imbalance could contribute to physical deconditioning experienced by astronauts due to its essential role in energy metabolism, cellular respiration, and oxygen transport.

Objectives: In this clinical exploratory study, we wanted to determine whether artificial gravity (AG) training modulated iron metabolism, RBC indices, and body lean mass in healthy male and female participants exposed to head-down tilt (HDT) bed rest, the reference ground-based model of microgravity.

Methods: We recruited 8 healthy female and 16 healthy male participants who were all exposed to HDT bed rest for 60 d.

A New Pathogenic Missense Variant in a Consanguineous North-African Family Responsible for a Highly Variable Aceruloplasminemia Phenotype: A Case-Report.

Aceruloplasminemia is a rare autosomal recessive inherited disorder. Mutations in the ceruloplasmin gene cause depressed ferroxidase activity leading to iron accumulation. The clinical phenotype is highly variable: anemia, retinopathy, diabetes mellitus, psychiatric disorders, and neurological symptoms including parkinsonian disorders and dementia are the main features of this disease.

Specific changes of erythroid regulators and hepcidin in patients infected by SARS-COV-2.

Iron metabolism is tightly linked to infectious and inflammatory signals through hepcidin synthesis. To date, iron homeostasis during SARS-CoV-2 infection has not yet been described. The aim of this study is to characterize the hepcidin and erythroid regulators (growth differentiation factor 15 (GDF-15) and erythroferrone (ERFE)) by measuring concentrations in plasma in context of COVID-19 disease.

Oxidative and glycolytic skeletal muscles deploy protective mechanisms to avoid atrophy under pathophysiological iron overload.

Background: Iron excess has been proposed as an essential factor in skeletal muscle wasting. Studies have reported correlations between muscle iron accumulation and atrophy, either through ageing or by using experimental models of secondary iron overload. However, iron treatments performed in most of these studies induced an extra-pathophysiological iron overload, more representative of intoxication or poisoning.

H Gene Knock-Out in a Mouse Model of Hereditary Hemochromatosis Affects Bodily Iron Isotope Compositions.

Hereditary hemochromatosis is a genetic iron overload disease related to a mutation within the HFE gene that controls the expression of hepcidin, the master regulator of systemic iron metabolism. The natural stable iron isotope composition in whole blood of control subjects is different from that of hemochromatosis patients and is sensitive to the amount of total iron removed by the phlebotomy treatment. The use of stable isotopes to unravel the pathological mechanisms of iron overload diseases is promising but hampered by the lack of data in organs involved in the iron metabolism.

Megaloblastic anemia-related iron overload and erythroid regulators: a case report.

Background: In ineffective erythropoiesis, hepcidin synthesis is suppressed by erythroid regulators, namely erythroferrone and growth differentiation factor-15. For the first time, the hypothesis that iron overload in megaloblastic anemia may be related to ineffective erythropoiesis is explored by describing the kinetics of hepcidin, erythroferrone, and growth differentiation factor-15 levels in a patient diagnosed with megaloblastic anemia associated with iron overload.

Case Presentation: An 81-year-old Caucasian male was admitted for fatigue.

Metallomic profile in non-cirrhotic hepatocellular carcinoma supports a phenomenon of metal metabolism adaptation in tumor cells.

We have previously described a form of hepatocellular carcinoma (HCC) in non-cirrhotic liver (HCC-NC) developed by Peruvian patients. We analyzed the metallomic profile in hepatic tissues from two independent cohorts exhibiting HCC-NC. Clinical, histopathological data, and HCC and non-tumoral liver (NTL) samples of 38 Peruvian and 38 French HCC-NC patients, were studied.

Simulated microgravity disturbs iron metabolism and distribution in humans: Lessons from dry immersion, an innovative ground-based human model.

The objective of the present study was to determine the effects of dry immersion, an innovative ground-based human model of simulated microgravity and extreme physical inactivity, on iron homeostasis and distribution. Twenty young healthy men were recruited and submitted to 5 days of dry immersion (DI). Fasting blood samples and MRI were performed before and after DI exposure to assess iron status, as well as hematological responses.

[Metals: common clinical applications in inductively coupled plasma mass spectrometry].

Inductively coupled plasma mass spectrometry (ICP-MS) is an analytical technique for inorganic, quantitative, and multi-elemental compounds commonly used in clinical biology. In recent years, it has gradually replaced atomic absorption techniques. It is based on the combination of an ion source formed of an inductively coupled plasma torch by a high-frequency electromagnetic generator, and a mass spectrometer, which allows the separation of ions generated according to their mass and energy.

Optical-Flow Based Nonlinear Weighted Prediction for SDR and Backward Compatible HDR Video Coding.

Tone Mapping Operators (TMO) designed for videos can be classified into two categories. In a first approach, TMOs are temporal filtered to reduce temporal artifacts and provide a Standard Dynamic Range (SDR) content with improved temporal consistency. This however does not improve the SDR coding Rate Distortion (RD) performances.

Ceruloplasmin deficiency does not induce macrophagic iron overload: lessons from a new rat model of hereditary aceruloplasminemia.

Hereditary aceruloplasminemia (HA), related to mutations in the ceruloplasmin () gene, leads to iron accumulation. Ceruloplasmin ferroxidase activity being considered essential for macrophage iron release, macrophage iron overload is expected, but it is not found in hepatic and splenic macrophages in humans. Our objective was to get a better understanding of the mechanisms leading to iron excess in HA.

Spleen iron, molybdenum, and manganese concentrations are coregulated in hepcidin-deficient and secondary iron overload models in mice.

Iron excess increases the hepatic expression of hepcidin, the systemic iron metabolism regulator that favors iron sequestration in the spleen. Genetic iron overload related to hepcidin insufficiency decreases the spleen iron concentration and increases hepatic iron concentration, whereas during secondary iron overload, the hepcidin expression increases together with spleen iron concentration in addition to hepatic iron concentrations increase. Links between iron metabolism and other metals being suggested, our aim was to investigate, during iron overload, the relationships between the hepatic hepcidin expression level and the hepatic and splenic concentrations of iron, manganese, copper, zinc, and molybdenum, determined using inductively coupled plasma mass spectrometry.

Optimal Adaptive Quantization Based on Temporal Distortion Propagation Model for HEVC.

Optimal adaptive quantization is one of the key points to optimize the coding efficiency of video encoders. The latest block-based video compression standards, such as high-efficiency video coding (HEVC), extensively use predictive coding techniques that create dependencies between blocks and increase the complexity of optimal block quantizers search. Specifically, the motion compensation is responsible for a dependency network connecting all blocks of the same GOP together.

Skeletal muscle ceramides do not contribute to physical-inactivity-induced insulin resistance.

Physical inactivity increases the risk to develop type 2 diabetes, a disease characterized by a state of insulin resistance. By promoting inflammatory state, ceramides are especially recognized to alter insulin sensitivity in skeletal muscle. The present study was designed to analyze, in mice, whether muscle ceramides contribute to physical-inactivity-induced insulin resistance.

Variable expressivity of HJV related hemochromatosis: "Juvenile" hemochromatosis?

Juvenile hemochromatosis is a rare autosomal recessive disease due to variants in the Hemojuvelin (HJV) gene. Although biological features mimic HFE hemochromatosis, clinical presentation is worst with massive iron overload diagnosed during childhood. Our study describes clinical features and results of genetic testing for a group of patients initially referred for a hepcidino-deficiency syndrome and for whom HJV hemochromatosis was finally diagnosed.

Iron excess upregulates SPNS2 mRNA levels but reduces sphingosine-1-phosphate export in human osteoblastic MG-63 cells.

Unlabelled: We aimed to study the mechanisms involved in bone-related iron impairment by using the osteoblast-like MG-63 cell line. Our results indicate that iron impact the S1P/S1PR signalizing axis and suggest that iron can affect the S1P process and favor the occurrence of osteoporosis during chronic iron overload.

Introduction: Systemic iron excess favors the development of osteoporosis, especially during genetic hemochromatosis.

Non-invasive measurement of liver iron concentration using 3-Tesla magnetic resonance imaging: validation against biopsy.

Objectives: To evaluate the performance and limitations of the R2* and signal intensity ratio (SIR) methods for quantifying liver iron concentration (LIC) at 3 T.

Methods: A total of 105 patients who underwent a liver biopsy with biochemical LIC (LIC) were included prospectively. All patients underwent a 3-T MRI scan with a breath-hold multiple-echo gradient-echo sequence (mGRE).