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Dermal filler complications and management
Published in Michael Parker, Charlie James, Fundamentals for Cosmetic Practice, 2022
Iron-binding proteins directly inhibit bacterial growth by decreasing the amount of available iron, with examples including transferrin, lactoferrin, ferritin and haemoglobin. This is why ferritin may be considered an acute-phase protein, with higher-than-expected circulating levels in the setting of acute infection. Iron is required almost universally by all known human pathogens for cellular functions such as DNA replication and respiration. Due to this, the human body has evolved to tightly regulate the amount of freely available iron, allowing it to starve pathogens of this precious resource. One key molecule in iron regulation is the hormone hepcidin, which functions by preventing the release of iron from intracellular stores into the systemic circulation through the iron export channel ferroportin. By keeping iron within cells, bacteria are unable to access it and their cellular processes are inhibited.
Micronutrients and Nutraceuticals: Effects on Exercise Performance
Published in Peter M. Tiidus, Rebecca E. K. MacPherson, Paul J. LeBlanc, Andrea R. Josse, The Routledge Handbook on Biochemistry of Exercise, 2020
Stella L. Volpe, Quentin Nichols
A major regulator of iron homeostasis is hepcidin, which is a hormone synthesized in the liver (77). Hepcidin plays a primary role in iron regulation by binding to the iron export protein ferroportin 1 (FPN1), thus inhibiting iron transport. Ferroportin 1 is located on the basolateral surface of the intestinal enterocytes and the plasma membrane of macrophages. By inhibiting ferroportin, hepcidin precludes iron from being exported, and thus, iron is sequestered in the cells. Hepcidin therefore decreases dietary iron absorption and decreases iron release from macrophages (5, 19, 54).
The Contribution of Iron and Transition Metal Micronutrients to Diabetes and Metabolic Disease
Published in Emmanuel C. Opara, Sam Dagogo-Jack, Nutrition and Diabetes, 2019
Lipika Salaye, Zhenzhong Bai, Donald A. McClain
Systemic and cellular iron metabolism have been the subject of excellent recent reviews [9–11] and will be only briefly recapitulated here (Figure 15.1). Intestinal free ferric (Fe3+) iron is reduced to ferrous Fe2+ by duodenal cytochrome B (DCTB) and enters duodenal enterocytes by way of the divalent metal-ion transporter 1 (DMT1) and possibly other carriers. Dietary heme is directly absorbed into enterocytes, where iron is released by heme oxygenase (HMOX). Ferrous iron exits the enterocytes through the iron export channel ferroportin (FPN). After oxidization by hephaestin (HEPH), Fe3+ binds to transferrin (Tf) in the blood, which in turn binds to transferrin receptors (TfR) on the surface of target cells. In most cells (Figure 15.1, lower right), after endocytosis of TfR1 and acidification of the endosome, iron is released, reduced by STEAP (6-transmembrane epithelial antigen of the prostate), and enters the cytosol through DMT1, where it is used (e.g., for heme or Fe-S-cluster synthesis in mitochondria) or, if in excess, sequestered by ferritin. Apoferritin secreted into the circulation is a marker for tissue iron stores, although the trigger for its secretion versus use to sequester more iron is not known. The intracellular trafficking of iron is much more complicated than indicated in the figure. For example, iron is highly controlled and chaperoned to its various targets, as ferrous iron or after iron-sulfur cluster synthesis, by mechanisms that are still under study [6].
Autophagy-dependent ferroptosis is involved in the development of endometriosis
Published in Gynecological Endocrinology, 2023
Hui Li, Huadi Yang, Shenyi Lu, Xinyan Wang, Xinhe Shi, Peiyu Mao
Ferroptosis is a type of cell death that is dependent on autophagy [22]. It can cause oxidative stress, lipid peroxidation, morphological changes of mitochondria, contributing to the pathophysiology of EMS [36]. Within the ovary, hypoxia-driven elevations in ROS levels can provoke autophagy in EMS cells [37]. While autophagy serves to eliminate damaged proteins and subcellular organelles to sustain cell viability, unrecoverable damage can trigger cell death in the intrafollicular microenvironment [38]. Abnormal expression of iron-specific autophagy-related genes and proteins has been detected in granulosa cells of patients experiencing infertility related to EMS [37]. In our study, the addition of Erastin, a ferroptosis inducer, it has been reported that it induces ferroptosis via ferroportin-mediated iron accumulation in EMS [23]. Erastin inhibited the cell viability, GPX4, p53, NCOA4 expression but promoted the iron content, FTH, FTMT, ROS, HO-1, LPO production, autophagy, and the number of the ferroptosis mitochondria compared to the EMS + si-Atg5 group, indicating that the ferroptosis is closely related to the autophagy in EMS. Consistently, iron excess in the peritoneal fluid of EMS interferes with blastocyst development, lowers GPX4 expression, and triggers lipid peroxidation. This implies that iron overload contributes to embryo toxicity and promotes ferroptosis [39].
Role of the BMP6 protein in breast cancer and other types of cancer
Published in Growth Factors, 2021
Andrea Marlene García Muro, Azaria García Ruvalcaba, Lourdes del Carmen Rizo de la Torre, Josefina Yoaly Sánchez López
Hepcidin is a hormone that induces ferroportin degradation in response to iron overload, inhibiting the exportation of recycled iron from senescent cells by macrophages, iron absorption from enterocytes, and iron storage from hepatocytes, its transcription is mainly regulated by BMP6 but also by IL-10, activinβ and negatively by erythroferrone (Blanchette-Farra et al. 2018; Sebastiani, Wilkinson, and Pantopoulos 2016; Ganz and Nemeth 2012), it is involved in the process of iron homeostasis and participates in the control of mammary tumor growth; both the expression of hepcidin and its target, the iron-exporting ferroportin, are used to predict BC prognosis; ferroportin is frequently decreased in BC cells and tissues while hepcidin is upregulated, thus increasing intracellular iron retention (Blanchette-Farra et al. 2018). In BC, hepcidin levels correspond to a greater degree to hepatic expression than to local expression and this expression has been related to BMP6 (Vela and Vela-Gaxha 2018); TGF-β1 and BMP6 could control the expression of hepcidin mRNA in an additive way (Chen et al. 2016).
Evaluation of Erythroferrone, Hepcidin, and Iron Overload Status in Iraqi Transfusion-Dependent β-Thalassemia Major Patients
Published in Hemoglobin, 2020
Hasan N.K. Smesam, Hasan A.Q. Albuthabhak, Sareh Arjmand, Hussein K. Al-Hakeim, Seyed Omid R. Siadat
Hepcidin, a small peptide hormone secreted by hepatocyte, and erythroferrone (ERFE) that inhibits the action of hepcidin, is among the central regulators of iron homeostasis in human plasma and promising therapeutic targets for iron disorders. Hepcidin inhibits iron influx into plasma by regulating the cellular concentration of the sole known cellular iron exporter called ferroportin [9,10]. It was found that hepcidin binds to the central cavity of ferroportin in the surface of enterocytes, macrophages and hepatocytes, and blocks its iron export activity. Furthermore, upon hepcidin-binding, conformational changes take place in ferroportin that associate with the exposure of its ubiquitination sites and, therefore, initiation of internalization and degradation [11]. Malfunction of the hepcidin-ferroportin axis underlies some common iron disorders, such as iron overload in β-TM, anemia of inflammation or cancer [12].