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Li B, Yu W, Verkhratsky A. Trace metals and astrocytes physiology and pathophysiology. Cell Calcium 2024; 118:102843. [PMID: 38199057 DOI: 10.1016/j.ceca.2024.102843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 01/03/2024] [Accepted: 01/03/2024] [Indexed: 01/12/2024]
Abstract
Several trace metals, including iron, copper, manganese and zinc are essential for normal function of the nervous system. Both deficiency and excessive accumulation of these metals trigger neuropathological developments. The central nervous system (CNS) is in possession of dedicated homeostatic system that removes, accumulates, stores and releases these metals to fulfil nervous tissue demand. This system is mainly associated with astrocytes that act as dynamic reservoirs for trace metals, these being a part of a global system of CNS ionostasis. Here we overview physiological and pathophysiological aspects of astrocyte-cantered trace metals regulation.
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Affiliation(s)
- Baoman Li
- Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China; Liaoning Province Key Laboratory of Forensic Bio-Evidence Sciences, China; China Medical University Centre of Forensic Investigation, China
| | - Weiyang Yu
- Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China; Liaoning Province Key Laboratory of Forensic Bio-Evidence Sciences, China; China Medical University Centre of Forensic Investigation, China
| | - Alexei Verkhratsky
- Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China; Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK; Achucarro Center for Neuroscience, Ikerbasque, Bilbao 48011, Spain; Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, Vilnius LT-01102, Lithuania.
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Palsa K, Neely EB, Baringer SL, Helmuth TB, Simpson IA, Connor JR. Brain iron acquisition depends on age and sex in iron-deficient mice. FASEB J 2024; 38:e23331. [PMID: 38031991 PMCID: PMC10691552 DOI: 10.1096/fj.202301596rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 11/09/2023] [Accepted: 11/13/2023] [Indexed: 12/01/2023]
Abstract
Adequate and timely delivery of iron is essential for brain development. The uptake of transferrin-bound (Tf) iron into the brain peaks at the time of myelination, whereas the recently discovered H-ferritin (FTH1) transport of iron into the brain continues to increase beyond the peak in myelination. Here, we interrogate the impact of dietary iron deficiency (ID) on the uptake of FTH1- and Tf-bound iron. In the present study, we used C57BL/6J male and female mice at a developing (post-natal day (PND) 15) and adult age (PND 85). In developing mice, ID results in increased iron delivery from both FTH1 and Tf for both males and females. The amount of iron uptake from FTH1 was higher than the Tf and this difference between the iron delivery was much greater in females. In contrast, in the adult model, ID was associated with increased brain iron uptake by both FTH1 and Tf but only in the males. There was no increased uptake from either protein in the females. Moreover, transferrin receptor expression on the microvasculature as well as whole brain iron, and H and L ferritin levels revealed the male brains became iron deficient but not the female brains. Last, under normal dietary conditions, 55 Fe uptake was higher in the developing group from both delivery proteins than in the adult group. These results indicate that there are differences in iron acquisition between the developing and adult brain for FTH1 and Tf during nutritional ID and demonstrate a level of regulation of brain iron uptake that is age and sex-dependent.
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Affiliation(s)
- Kondaiah Palsa
- Department of Neurosurgery, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | - Elizabeth B. Neely
- Department of Neurosurgery, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | - Stephanie L. Baringer
- Department of Neurosurgery, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | - Timothy B. Helmuth
- Department of Neurosurgery, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | - Ian A. Simpson
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | - James R. Connor
- Department of Neurosurgery, Penn State College of Medicine, Hershey, Pennsylvania, USA
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Baj J, Kowalska B, Barbachowska A, Forma A, Flieger M, Majerek D, Teresiński G, Flieger W, Portincasa P, Buszewicz G, Radzikowska-Büchner E, Flieger J. Linking Metallic Micronutrients and Toxic Xenobiotics to Atherosclerosis and Fatty Liver Disease-Postmortem ICP-MS Analysis of Selected Human Tissues. Nutrients 2023; 15:3458. [PMID: 37571395 PMCID: PMC10420647 DOI: 10.3390/nu15153458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 07/30/2023] [Accepted: 08/02/2023] [Indexed: 08/13/2023] Open
Abstract
Dyslipidaemia is a disorder of the lipid metabolism, caused mainly by poor eating habits. The most severe consequence of an inappropriate diet is the development of atherosclerosis and hepatic steatosis. It is generally believed that a change in nutrition, and increased physical activity can eliminate these health problems. The contemporary research and therapies used to treat dyslipidemia mainly focus on lowering the triglyceride and cholesterol levels. However, disturbances in trace element homeostasis or the accumulation of toxic elements can also affect physiological processes, and be involved in the development of metabolically mediated diseases. The present study aimed to determine the mineral profiles of liver and brain tissues collected at autopsy (n = 39) in groups of people with hepatic steatosis (n = 5), atherosclerosis (n = 9), hepatic steatosis, and atherosclerosis (n = 16), and others without the selected disorders (n = 9). Concentrations of 51 elements were analysed via inductively coupled plasma mass spectrometry (ICP-MS) after the initial wet mineralisation of the samples with nitric acid. The results obtained allow us to conclude that the hepatic steatosis group suffers from a deficiency of important trace elements, such as copper, zinc, and molybdenum (p < 0.05), whereas the group with atherosclerosis is characterised by elevated levels of cadmium in the liver tissue (p = 0.01). Analysing the mean values of the element concentrations measured in 11 brain areas, statistically significant higher levels of calcium and copper (p < 0.001) were found in the atherosclerosis group, compared to the hepatic steatosis group, confirming the involvement of these elements in the pathogenesis of atherosclerosis. In addition, an accumulation of cadmium, lead, titanium, and strontium in the brain tissue was observed in the atherosclerosis group. While the accumulation of individual elements differs in different parts of the brain, the differences in the cadmium content (p < 0.05) between the study groups apply to the whole brain, except for the nucleus accumbens septi area, where a statistically significant titanium accumulation occurs in the atherosclerosis and steatosis groups, compared to the others (p < 0.05). In addition, the disruption of elemental homeostasis in the brain of a single case with bipolar disorder, and a case with hip replacement was observed. Our results confirm the involvement of chemical elements in the pathogenesis of selected metabolic diseases, and the need for further studies in larger populations.
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Affiliation(s)
- Jacek Baj
- Chair and Department of Anatomy, Medical University of Lublin, 20-090 Lublin, Poland; (A.F.); (W.F.)
| | - Beata Kowalska
- Department of Water Supply and Wastewater Disposal, Lublin University of Technology, 20-618 Lublin, Poland;
| | - Aleksandra Barbachowska
- Department of Plastic, Reconstructive and Burn Surgery, ul. Krasnystawska, 21-010 Łęczna, Poland;
| | - Alicja Forma
- Chair and Department of Anatomy, Medical University of Lublin, 20-090 Lublin, Poland; (A.F.); (W.F.)
| | - Michał Flieger
- Chair and Department of Forensic Medicine, Medical University of Lublin, 20-090 Lublin, Poland; (M.F.); (G.T.); (G.B.)
| | - Dariusz Majerek
- Department of Applied Mathematics, University of Technology, 20-618 Lublin, Poland;
| | - Grzegorz Teresiński
- Chair and Department of Forensic Medicine, Medical University of Lublin, 20-090 Lublin, Poland; (M.F.); (G.T.); (G.B.)
| | - Wojciech Flieger
- Chair and Department of Anatomy, Medical University of Lublin, 20-090 Lublin, Poland; (A.F.); (W.F.)
| | - Piero Portincasa
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Meical School, 70124 Bari, Italy;
| | - Grzegorz Buszewicz
- Chair and Department of Forensic Medicine, Medical University of Lublin, 20-090 Lublin, Poland; (M.F.); (G.T.); (G.B.)
| | | | - Jolanta Flieger
- Department of Analytical Chemistry, Medical University of Lublin, 20-093 Lublin, Poland
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Schreiner OD, Schreiner TG. Iron chelators as a therapeutic option for Alzheimer's disease-A mini-review. FRONTIERS IN AGING 2023; 4:1234958. [PMID: 37602277 PMCID: PMC10433644 DOI: 10.3389/fragi.2023.1234958] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 07/17/2023] [Indexed: 08/22/2023]
Abstract
Neurodegenerative disorders, particularly Alzheimer's disease (AD), remain a great challenge regarding the finding of effective treatment, one main reason being the incomplete understanding of their etiology. With many intensely debated hypotheses, a newer approach based on the impact of iron imbalance in sustaining neurodegeneration in the central nervous system becomes increasingly popular. Altered iron homeostasis leads to increased iron accumulation in specific brain areas, explaining the clinical picture of AD patients. Moreover, growing evidence sustains the significant impact of iron metabolism in relationship to other pathological processes encountered in the AD-affected brain, such as the amyloidogenic pathway, chronic inflammation, or oxidative stress. In this context, this mini-review aims to summarize the novel data from the continuously expanding literature on this topic in a didactic manner. Thus, in the first part, the authors briefly highlight the most relevant aspects related to iron absorption, transport, regulation, and elimination at the cerebral level, focusing on the role of the blood-brain barrier and the newer concept of ferroptosis. Subsequently, currently available iron chelation therapies are discussed, including an overview of the most relevant clinical trials on this topic. In the final part, based on the latest results from in vitro and in vivo studies, new research directions are suggested to enhance the development of effective antidementia therapies.
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Affiliation(s)
- Oliver Daniel Schreiner
- Grigore T. Popa University of Medicine and Pharmacy, Iasi, Romania
- Medical Oncology Department, Regional Institute of Oncology, Iasi, Romania
| | - Thomas Gabriel Schreiner
- Grigore T. Popa University of Medicine and Pharmacy, Iasi, Romania
- Faculty of Electrical Engineering and Information Technology, Gheorghe Asachi Technical University of Iasi, Iasi, Romania
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, Bucharest, Romania
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Baringer SL, Palsa K, Spiegelman VS, Simpson IA, Connor JR. Apo- and holo-transferrin differentially interact with hephaestin and ferroportin in a novel mechanism of cellular iron release regulation. J Biomed Sci 2023; 30:36. [PMID: 37277838 PMCID: PMC10243088 DOI: 10.1186/s12929-023-00934-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 05/28/2023] [Indexed: 06/07/2023] Open
Abstract
BACKGROUND Apo- (iron free) and holo- (iron bound) transferrin (Tf) participate in precise regulation of brain iron uptake at endothelial cells of the blood-brain barrier. Apo-Tf indicates an iron-deficient environment and stimulates iron release, while holo-Tf indicates an iron sufficient environment and suppresses additional iron release. Free iron is exported through ferroportin, with hephaestin as an aid to the process. Until now, the molecular mechanisms of apo- and holo-Tf influence on iron release was largely unknown. METHODS Here we use a variety of cell culture techniques, including co-immunoprecipitation and proximity ligation assay, in iPSC-derived endothelial cells and HEK 293 cells to investigate the mechanism by which apo- and holo-Tf influence cellular iron release. Given the established role of hepcidin in regulating cellular iron release, we further explored the relationship of hepcidin to transferrin in this model. RESULTS We demonstrate that holo-Tf induces the internalization of ferroportin through the established ferroportin degradation pathway. Furthermore, holo-Tf directly interacts with ferroportin, whereas apo-Tf directly interacts with hephaestin. Only pathophysiological levels of hepcidin disrupt the interaction between holo-Tf and ferroportin, but similar hepcidin levels are unable to interfere with the interaction between apo-Tf and hephaestin. The disruption of the holo-Tf and ferroportin interaction by hepcidin is due to hepcidin's ability to more rapidly internalize ferroportin compared to holo-Tf. CONCLUSIONS These novel findings provide a molecular mechanism for apo- and holo-Tf regulation of iron release from endothelial cells. They further demonstrate how hepcidin impacts these protein-protein interactions, and offer a model for how holo-Tf and hepcidin cooperate to suppress iron release. These results expand on our previous reports on mechanisms mediating regulation of brain iron uptake to provide a more thorough understanding of the regulatory mechanisms mediating cellular iron release in general.
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Affiliation(s)
- Stephanie L Baringer
- Department of Neurosurgery, Penn State College of Medicine, 500 University Drive, Hershey, PA, 17033, USA
| | - Kondaiah Palsa
- Department of Neurosurgery, Penn State College of Medicine, 500 University Drive, Hershey, PA, 17033, USA
| | | | - Ian A Simpson
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA, USA
| | - James R Connor
- Department of Neurosurgery, Penn State College of Medicine, 500 University Drive, Hershey, PA, 17033, USA.
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Baringer SL, Lukacher AS, Palsa K, Kim H, Lippmann ES, Spiegelman VS, Simpson IA, Connor JR. Amyloid-β exposed astrocytes induce iron transport from endothelial cells at the blood-brain barrier by altering the ratio of apo- and holo-transferrin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.15.540795. [PMID: 37292926 PMCID: PMC10245582 DOI: 10.1101/2023.05.15.540795] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Excessive brain iron accumulation is observed in early in the onset of Alzheimer's disease, notably prior to widespread proteinopathy. These findings suggest that increases in brain iron levels are due to a dysregulation of the iron transport mechanism at the blood-brain barrier. Astrocytes release signals (apo- and holo-transferrin) that communicate brain iron needs to endothelial cells in order to modulate iron transport. Here we use iPSC-derived astrocytes and endothelial cells to investigate how early-disease levels of amyloid-β disrupt iron transport signals secreted by astrocytes to stimulate iron transport from endothelial cells. We demonstrate that conditioned media from astrocytes treated with amyloid-β stimulates iron transport from endothelial cells and induces changes in iron transport pathway protein levels. The mechanism underlying this response begins with increased iron uptake and mitochondrial activity by the astrocytes which in turn increases levels of apo-transferrin in the amyloid-β conditioned astrocyte media leading to increased iron transport from endothelial cells. These novel findings offer a potential explanation for the initiation of excessive iron accumulation in early stages of Alzheimer's disease. What's more, these data provide the first example of how the mechanism of iron transport regulation by apo- and holo-transferrin becomes misappropriated in disease to detrimental ends. The clinical benefit from understanding early dysregulation in brain iron transport in AD cannot be understated. If therapeutics can target this early process, they could possibly prevent the detrimental cascade that occurs with excessive iron accumulation. Significance Statement Excessive brain iron accumulation is hallmark pathology of Alzheimer's disease that occurs early in the disease staging and before widespread proteinopathy deposition. This overabundance of brain iron has been implicated to contribute to disease progression, thus understandingthe mechanism of early iron accumulation has significant therapeutic potential to slow to halt disease progression. Here, we show that in response to low levels of amyloid-β exposure, astrocytes increase their mitochondrial activity and iron uptake, resulting in iron deficient conditions. Elevated levels of apo (iron free)-transferrin stimulate iron release from endothelial cells. These data are the first to propose a mechanism for the initiation of iron accumulation and the misappropriation of iron transport signaling leading to dysfunctional brain iron homeostasis and resultant disease pathology.
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Palsa K, Baringer SL, Shenoy G, Spiegelman VS, Simpson IA, Connor JR. Exosomes are involved in iron transport from human blood-brain barrier endothelial cells and are modified by endothelial cell iron status. J Biol Chem 2023; 299:102868. [PMID: 36603765 PMCID: PMC9929479 DOI: 10.1016/j.jbc.2022.102868] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 12/24/2022] [Accepted: 12/26/2022] [Indexed: 01/04/2023] Open
Abstract
Iron is essential for normal brain development and function. Hence, understanding the mechanisms of iron efflux at the blood-brain barrier and their regulation are critical for the establishment of brain iron homeostasis. Here, we have investigated the role of exosomes in mediating the transfer of H-ferritin (FTH1)- or transferrin (Tf)-bound iron across the blood-brain barrier endothelial cells (BBBECs). Our study used ECs derived from human-induced pluripotent stem cells that are grown in bicameral chambers. When cells were exposed to 55Fe-Tf or 55Fe-FTH1, the 55Fe activity in the exosome fraction in the basal chamber was significantly higher compared to the supernatant fraction. Furthermore, we determined that the release of endogenous Tf, FTH1, and exosome number is regulated by the iron concentration of the endothelial cells. Moreover, the release of exogenously added Tf or FTH1 to the basal side via exosomes was significantly higher when ECs were iron loaded compared to when they were iron deficient. The release of exosomes containing iron bound to Tf or FTH1 was independent of hepcidin regulation, indicating this mechanism by-passes a major iron regulatory pathway. A potent inhibitor of exosome formation, GW4869, reduced exosomes released from the ECs and also decreased the Tf- and FTH1-bound iron within the exosomes. Collectively, these results indicate that iron transport across the blood-brain barrier is mediated via the exosome pathway and is modified by the iron status of the ECs, providing evidence for a novel alternate mechanism of iron transport into the brain.
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Affiliation(s)
- Kondaiah Palsa
- Department of Neurosurgery, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | - Stephanie L Baringer
- Department of Neurosurgery, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | - Ganesh Shenoy
- Department of Neurosurgery, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | - Vladimir S Spiegelman
- Department of Pediatrics, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | - Ian A Simpson
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, Pennsylvania, USA
| | - James R Connor
- Department of Neurosurgery, Penn State College of Medicine, Hershey, Pennsylvania, USA.
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Baringer S, Palsa K, Simpson IA, Connor JR. Apo- and holo- transferrin differentially interact with ferroportin and hephaestin to regulate iron release at the blood-brain barrier. RESEARCH SQUARE 2023:rs.3.rs-2429356. [PMID: 36711476 PMCID: PMC9882672 DOI: 10.21203/rs.3.rs-2429356/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Background : Apo- (iron free) and holo- (iron bound) transferrin (Tf) participate in precise regulation of brain iron uptake at endothelial cells of the blood-brain barrier. Apo-Tf indicates an iron deficient environment and stimulates iron release, while holo-Tf indicates an iron sufficient environment and suppresses additional iron release. Free iron is exported through ferroportin, with hephaestin as an aid to the process. Until now, the molecular mechanism of apo- and holo-Tf's influence on iron release was largely unknown. Methods : Here we use a variety of cell culture techniques, including co-immunoprecipitation and proximity ligation assay, in iPSC-derived endothelial cells and HEK 293 cells to investigate the mechanism of apo- and holo-Tf's influence over iron release. We placed our findings in physiological context by further deciphering how hepcidin played a role in this mechanism as well. Results : We demonstrate that holo-Tf induces the internalization of ferroportin through the established ferroportin degradation pathway. Furthermore, holo-Tf directly binds to ferroportin, whereas apo-Tf directly binds to hephaestin. Only pathological levels of hepcidin disrupt the interaction between holo-Tf and ferroportin, and no amount of hepcidin disrupts the interaction between apo-Tf and hephaestin. The disruption of the holo-Tf and ferroportin interaction by hepcidin is due to hepcidin's ability to rapidly internalize ferroportin compared to holo-Tf. Conclusions : These novel findings provide a molecular mechanism for apo- and holo-Tf regulation of iron release from endothelial cells. They further demonstrate how hepcidin impacts these protein-protein interactions, and offer a model for how holo-Tf and hepcidin corporate to suppress iron release. We have established a more thorough understanding of the mechanisms behind iron release regulation with great clinical impact for a variety of neurological conditions in which iron release is dysregulated.
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Baringer SL, Palsa K, Simpson IA, Connor JR. Apo- and holo- transferrin differentially interact with ferroportin and hephaestin to regulate iron release at the blood-brain barrier. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.10.522344. [PMID: 36712094 PMCID: PMC9882075 DOI: 10.1101/2023.01.10.522344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Background Apo- (iron free) and holo- (iron bound) transferrin (Tf) participate in precise regulation of brain iron uptake at endothelial cells of the blood-brain barrier. Apo-Tf indicates an iron deficient environment and stimulates iron release, while holo-Tf indicates an iron sufficient environment and suppresses additional iron release. Free iron is exported through ferroportin, with hephaestin as an aid to the process. Until now, the molecular mechanism of apo- and holo-Tf's influence on iron release was largely unknown. Methods Here we use a variety of cell culture techniques, including co-immunoprecipitation and proximity ligation assay, in iPSC-derived endothelial cells and HEK 293 cells to investigate the mechanism of apo- and holo-Tf's influence over iron release. We placed our findings in physiological context by further deciphering how hepcidin played a role in this mechanism as well. Results We demonstrate that holo-Tf induces the internalization of ferroportin through the established ferroportin degradation pathway. Furthermore, holo-Tf directly binds to ferroportin, whereas apo-Tf directly binds to hephaestin. Only pathological levels of hepcidin disrupt the interaction between holo-Tf and ferroportin, and no amount of hepcidin disrupts the interaction between apo-Tf and hephaestin. The disruption of the holo-Tf and ferroportin interaction by hepcidin is due to hepcidin's ability to rapidly internalize ferroportin compared to holo-Tf. Conclusions These novel findings provide a molecular mechanism for apo- and holo-Tf regulation of iron release from endothelial cells. They further demonstrate how hepcidin impacts these protein-protein interactions, and offer a model for how holo-Tf and hepcidin corporate to suppress iron release. We have established a more thorough understanding of the mechanisms behind iron release regulation with great clinical impact for a variety of neurological conditions in which iron release is dysregulated.
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Affiliation(s)
| | - Kondaiah Palsa
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA
| | - Ian A. Simpson
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA, USA
| | - James R. Connor
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA
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Palsa K, Connor JR, Flanagan J, Hines EA. H-ferritin in sows' colostrum- and milk-derived extracellular vesicles: a novel iron delivery concept. J Anim Sci 2023; 101:skad013. [PMID: 36629252 PMCID: PMC9910394 DOI: 10.1093/jas/skad013] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 01/09/2023] [Indexed: 01/12/2023] Open
Abstract
Iron deficiency anemia is a significant problem in piglets, as they are born with insufficient iron stores for supporting their rapid body growth. Further, sows' milk contains inadequate iron levels for meeting the demands of piglet rapid growth in the pre-wean stage. The forms of iron present in the milk are essential to understanding bioavailability and potential routes for supplementing iron to mitigate iron deficiency anemia in piglets. Recently, our studies showed that H-ferritin (FTH1) is involved in iron transport to different tissues and can be used as an oral iron supplement to correct iron deficiency in rats and monkeys. In this study, we investigate the FTH1 levels in colostrum and milk in Yorkshires-crossbred sows (n = 27) and collected samples at the 1st, 15th, and 28th days of lactation to measure FTH1. Colostrum and milk were found to have FTH1, but there is no significant difference between the different days of lactation. FTH1 has been observed to be enriched in extracellular vesicles (EVs) of other species, and therefore examined the EVs in the samples. Colostrum-derived EVs were enriched with L-ferritin compared to FTH1, while in milk-derived EVs, only FTH1 was detected (P = 0.04). In milk-derived EVs, FTH1 was significantly higher (P = 0.021; P = 006) than FTH1 in colostrum-derived EVs. Furthermore, FTH1 levels of milk-derived EVs were significantly higher (P = 0.0002; P = 0004) than whole milk and colostrum FTH1. These results indicate that FTH1 is enriched in the milk-derived EVs and suggest that EVs play a predominant role in the FTH1 delivery mechanism for the piglet. The extent to which FTH1 in EVs accounts for the overall iron delivery mechanism in piglets is yet to be determined.
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Affiliation(s)
- Kondaiah Palsa
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA
| | - James R Connor
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA
| | - John Flanagan
- Department of Biochemistry and Molecular biology, Penn State College of Medicine, Hershey, PA, USA
| | - Elizabeth A Hines
- Department of Animal Science, College of Agricultural Sciences, Penn State University, University Park, PA, USA
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Wawrzyniak A, Balawender K, Lalak R, Staszkiewicz R, Boroń D, Grabarek BO. Oligodendrocytes in the periaqueductal gray matter and the corpus callosum in adult male and female domestic sheep. Brain Res 2022; 1792:148036. [DOI: 10.1016/j.brainres.2022.148036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/22/2022] [Accepted: 07/27/2022] [Indexed: 11/02/2022]
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