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Published in Debasis Bagchi, Manashi Bagchi, Metal Toxicology Handbook, 2020
Amit Madeshiya, Pradipta Banerjee, Suman Santra, Nandini Ghosh, Sayantani Karmakar, Debasis Bagchi, Sashwati Roy, Amitava Das
Cells in the redox state are usually dependent on iron (and copper) redox couple and are maintained within strict physiological limits. Rate of iron absorption in the proximal intestine and rate of iron released are prevented by homeostatic mechanism. Unused cellular iron by other ferroproteins accumulates in ferretin, and its iron-binding capacity is limited. Hemochromatosis is a typical condition where patients suffer from iron overload causing severe organ damage. Interestingly, free iron can generate damaging reactive free radicals via the Fenton reaction [6] (Figure 1.1). Free iron has deleterious effects. When an organism is overloaded with iron, the Fenton reaction plays a significant role in vivo. The superoxide radicals generated participate in the Haber–Weiss reaction. It is a combination of the Fenton reaction and the reduction of Fe(III) by superoxide (Figure 1.1).
Nanoencapsulation of Iron for Nutraceuticals
Published in Bhupinder Singh, Minna Hakkarainen, Kamalinder K. Singh, NanoNutraceuticals, 2019
Naveen Shivanna, Hemanth Kumar Kandikattu, Rakesh Kumar Sharma, Teenu Sharma, Farhath Khanum
Excess of iron, or overload of iron, is termed as hemochromatosis, wherein iron accumulates in the body. The most important factor is heredity, a genetic disorder with a genetic defect in HLA-H gene region on chromosome 6, leading to low level of hepcidin, a key regulatory enzyme for entry of iron into the circulatory system, resulting eventually in excessive iron and hemochromatosis (Serra et al., 2009). Repeated blood transfusion results in a condition called transfusional iron overload. Excess in the availability of iron to bind iron transport protein transferrin leads to iron toxicity. Excessive levels of free iron in the blood react with peroxides, leading to the generation of highly reactive free radicals that can damage macromolecules such as proteins, lipids, DNA, and other cellular components through Fenton reaction (Eaton and Qian, 2002). Iron toxicity is also observed in aging disorders such as atherosclerosis, Alzheimer’s disease, and Parkinson’s disease (Altamura and Muckenthaler, 2009).
Metal Exposure and Toxic Responses
Published in Stephen K. Hall, Joana Chakraborty, Randall J. Ruch, Chemical Exposure and Toxic Responses, 2020
Chronic exposure to or excessive intake of iron may lead to hemosiderosis or hemochromatosis. Hemosiderosis refers to a condition in which there is generalized increased iron content in the body tissues, particularly the liver and reticuloendothelial system. Hemochromatosis, on the other hand, indicates demonstrable histologic hemosiderosis and diffused fibrotic changes of the affected organ.
Endogenous doesn’t always mean innocuous: a scoping review of iron toxicity by inhalation
Published in Journal of Toxicology and Environmental Health, Part B, 2020
Jody Morgan, Robin Bell, Alison L. Jones
Iron has long been considered one of the more biologically innocuous heavy metals, in part due to its high concentration in the human body and central role in human physiology. As such, this metal has often been ignored in studies examining the toxicology of PM. However, transition metal content and Fe mobilization are both associated with adverse health effects attributed to PM (Wu, Jin, and Carlsten 2018). Poorly liganded Fe has been implicated in a number of neurological diseases including Parkinson’s, Huntington’s, and Alzheimer’s diseases (Kell 2010). Genetic hemochromatosis patients, who possess an overload of Fe, suffer complications involving hepatic failure from cirrhosis or hepatocellular carcinoma with rates 93-240-fold higher than age-matched controls (Toyokuni 2002, 2009). A possible pathway to injury is the production of reactive oxygen species (ROS) when transition metals, such as Fe, are present, which leads to inflammation and subsequent injury (Funke et al. 2013; Wu, Ding, and Sun 2013a). Due to the inherent risks associated with these humans have extensive pathways for dealing with free Fe (Dev and Babitt 2017); however, when these pathways are overwhelmed via excessive exposure or genetic variability between individuals, this may lead to injury or illness.
Development of a fluorometric measurement system used in biological samples upon the determination of iron (II) metal ion
Published in Preparative Biochemistry & Biotechnology, 2021
Yavuz Selim Toksöz, İbrahim Ethem Özyiğit, Çiğdem Bilen, Nergis Arsu, Emine Karakuş
Iron metabolism has a critical role at cellular and organismal levels and also has a bioavailability property in immune cells homeostasis and inflammation. Iron is one of the most excessive element in the world and necessary for almost all organisms.[50–52] Iron is used for polymerization processes and metabolic reactions such as oxidation–reduction, hydrolysis, hemoglobin and myoglobin formations and stabilization.[53–55] Soluble iron, which is fundamental for electron transfer and ligands binding reactions, is retained by the active groups of extracellular polymeric substances and proteins.[56–58] It has one of the most widespread and biologically relevant oxidation state as ferrous ion, Fe(II) which is more soluble, bio-active and bioavailable than its ferric Fe(III) form.[50] Moreover, Fe(II) is not only essential cofactor for a number of enzymes involved in neurotransmitter synthesis, including serotonin, norepinephrine, dopamine and DNA synthesis, but also used for gene regulation, binding and transport of oxygen, regulation of cell growth, differentiation in plants and different organisms.[59–61] On the other hand, iron level in biological samples is critically important to cause of the consistence of reactive oxygen species and contributes to diabetic complications.[62] The well-established disorders related to iron metabolism are anemia resulting from iron deficiency and hemochromatosis caused by extreme iron levels.[63] Considering all these factors, it is important to determine trace amounts of Fe(II) in biological samples.
Uses and potential for cardiac magnetic resonance imaging in patients with cardiac resynchronisation pacemakers
Published in Expert Review of Medical Devices, 2019
If appropriate precautions are taken, CMR is viable in heart failure patients for a broad set of indications and increasingly benefit CRT workup: Assessment of etiology of heart failure – For a selection of patients it is helpful to investigate the cause of left ventricular systolic dysfunction. This may influence treatment, for example, in cases of hemochromatosis or Anderson-Fabry disease resulting in iron chelation or enzyme replacement, respectively.Assessment of ischemia or fibrosis – Late gadolinium enhancement is utilized to evaluate fibrosis and scar formation. This technique has been validated against histopathology [19] and creates a large contrast between normal and scarred tissue. The distribution pattern of these tissue types can be analyzed to distinguish between ischaemic and non-ischaemic pathologies. This information can then be used to identify ideal sites for LV lead implantation by avoiding areas of scar tissue resulting in a lower mortality and hospitalization rate [20]. Notably, imaging packages have also been developed for single-photon emission computed tomography to complement standard catheter laboratory-based fluoroscopy leading to improved CRT outcomes via placement away from scar tissue [21,22]Assessment of ventricular parameters, specifically; volume, mass, and ejection fraction.Investigating wall motion – The myocardial tissue usually moves in three planes: radially, longitudinally, and circumferentially. With LV pacing active it would be expected that wall motion would return to a more normalized movement enabling the relatively small organ to generate a large amount of force. Conventional MRI gives a high-quality image of the heart with the ability to analyze motion and the displacement of the inner and outer wall. This technique allows measurement of radial strain to be made relatively accurately in a routine scan. Importantly, radial strain is generally the largest strain subtype and associated with wall thickening [23]. The other types of strain assessment require more advanced imaging techniques. Wall motion patterns with an appropriately placed left ventricular lead have been independently linked to CRT response [24].