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Tyczyńska M, Hunek G, Szczasny M, Brachet A, Januszewski J, Forma A, Portincasa P, Flieger J, Baj J. Supplementation of Micro- and Macronutrients-A Role of Nutritional Status in Non-Alcoholic Fatty Liver Disease. Int J Mol Sci 2024; 25:4916. [PMID: 38732128 PMCID: PMC11085010 DOI: 10.3390/ijms25094916] [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: 03/19/2024] [Revised: 04/28/2024] [Accepted: 04/29/2024] [Indexed: 05/13/2024] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a condition in which the pathological cumulation of fat with coexisting inflammation and damage of hepatic cells leads to progressive dysfunctions of the liver. Except for the commonly well-known major causes of NAFLD such as obesity, dyslipidemia, insulin resistance, or diabetes, an unbalanced diet and imbalanced nutritional status should also be taken into consideration. In this narrative review, we summarized the current knowledge regarding the micro- and macronutrient status of patients suffering from NAFLD considering various diets and supplementation of chosen supplements. We aimed to summarize the knowledge indicating which nutritional impairments may be associated with the onset and progression of NAFLD at the same time evaluating the potential therapy targets that could facilitate the healing process. Except for the above-mentioned objectives, one of the most important aspects of this review was to highlight the possible strategies for taking care of NAFLD patients taking into account the challenges and opportunities associated with the micronutrient status of the patients. The current research indicates that a supplementation of chosen vitamins (e.g., vitamin A, B complex, C, or D) as well as chosen elements such as zinc may alleviate the symptoms of NAFLD. However, there is still a lack of sufficient data regarding healthy ranges of dosages; thus, further research is of high importance in this matter.
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Affiliation(s)
- Magdalena Tyczyńska
- Department of Correct, Clinical and Imaging Anatomy, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin, Poland;
| | - Gabriela Hunek
- Chair and Department of Forensic Medicine, Medical University of Lublin, Jaczewskiego 8b, 20-090 Lublin, Poland; (G.H.); (A.B.)
| | - Martyna Szczasny
- Chair and Department of Anatomy, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin, Poland; (M.S.); (J.J.)
| | - Adam Brachet
- Chair and Department of Forensic Medicine, Medical University of Lublin, Jaczewskiego 8b, 20-090 Lublin, Poland; (G.H.); (A.B.)
| | - Jacek Januszewski
- Chair and Department of Anatomy, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin, Poland; (M.S.); (J.J.)
| | - Alicja Forma
- Chair and Department of Forensic Medicine, Medical University of Lublin, Jaczewskiego 8b, 20-090 Lublin, Poland; (G.H.); (A.B.)
| | - Piero Portincasa
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, 70124 Bari, Italy;
| | - Jolanta Flieger
- Department of Analytical Chemistry, Medical University of Lublin, Chodźki 4A, 20-093 Lublin, Poland;
| | - Jacek Baj
- Chair and Department of Anatomy, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin, Poland; (M.S.); (J.J.)
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Yadav S, Saini NK, Kulshreshtha D, Mukhopadhyay CK. Lipopolysaccharide inhibits translation of iron chaperone PCBP1 to regulate inflammatory cytokine response in macrophage. Cytokine 2024; 174:156456. [PMID: 38061091 DOI: 10.1016/j.cyto.2023.156456] [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: 09/29/2023] [Revised: 11/09/2023] [Accepted: 11/26/2023] [Indexed: 01/01/2024]
Abstract
Macrophages play a key role in maintaining systemic iron homeostasis and immunity. During pro-inflammatory stage macrophages retain iron due to the decrease of the unique iron exporter ferroportin. Increased cellular iron is sequestered in to storage protein ferritin by iron chaperone poly(rC)-binding protein 1 (PCBP1). However, the fate of PCBP1 and its interaction with ferritin in pro-inflammatory macrophages has not been studied so far. Here we report that PCBP1 protein level is down-regulated in lipopolysaccharide (LPS) treated macrophages. LPS did not alter PCBP1 mRNA and protein stability suggesting inhibition of translation as a mechanism of PCBP1 down-regulation that was confirmed by 35S-methionine incorporation assay. PCBP1 interacts with ferritin-H (Ft-H) subunit to load iron into ferritin. We detected a decreased interaction between PCBP1 and Ft-H after LPS-stimulation. As a result iron loading in to ferritin was affected with simultaneous increase in labile iron pool (LIP). Pre-treatment of cells with iron chelator dampened LPS-induced expression of TNF-α, IL-1β and IL-6 mRNA. Silencing of PCBP1 increased the magnitude of expression of these cytokines compared to control siRNA transfected LPS-treated macrophages. In contrast, overexpression of PCBP1 resulted a decrease in expression of these cytokines compared to vector transfected macrophages. Our results reveal a novel regulation of PCBP1 and its role in expression of cytokines in LPS-induced pro-inflammatory macrophages.
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Affiliation(s)
- Sameeksha Yadav
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067, India
| | - Neeraj K Saini
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067, India
| | - Diksha Kulshreshtha
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067, India
| | - Chinmay K Mukhopadhyay
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067, India.
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Shi JF, Liu Y, Wang Y, Gao R, Wang Y, Liu J. Targeting ferroptosis, a novel programmed cell death, for the potential of alcohol-related liver disease therapy. Front Pharmacol 2023; 14:1194343. [PMID: 37214434 PMCID: PMC10196366 DOI: 10.3389/fphar.2023.1194343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 04/27/2023] [Indexed: 05/24/2023] Open
Abstract
Ferroptosis is a new iron-dependent cell death mode, which is different from the other types of programmed cell death, such as apoptosis, necrosis, and autophagy. Ferroptosis is characterized by a process in which fatal lipids from lipid peroxidation accumulate in cells and eventually lead to cell death. Alcohol-related liver disease (ALD) is a type of liver injury caused by excessive alcohol intake. Alcohol-related liver disease is a broad-spectrum disease category, which includes fatty liver, steatohepatitis, hepatitis, cirrhosis, and hepatocellular tumors. Recent studies have found that ferroptosis is involved in the pathological development of non-viral liver diseases. Therefore, ferroptosis may be an ideal target for the treatment of non-viral liver diseases. In this review article, we will elaborate the molecular mechanism and regulatory mechanism of ferroptosis, explore the key role of ferroptosis in the Alcohol-related liver disease process, and summarize the existing targeted ferroptosis drugs and their feasibility for the treatment of Alcohol-related liver disease.
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Affiliation(s)
- Jing-Fen Shi
- Institute for Health Policy and Hospital Management, Sichuan Academy of Medical Science and Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Wenjiang District People’s Hospital of Chengdu, Chengdu, China
| | - Yu’e Liu
- Tongji University Cancer Center, Shanghai Tenth People’s Hospital of Tongji University, School of Medicine, Tongji University, Shanghai, China
| | - Yan Wang
- Wenjiang District People’s Hospital of Chengdu, Chengdu, China
| | - Ru Gao
- Wenjiang District People’s Hospital of Chengdu, Chengdu, China
| | - Yi Wang
- Department of Critical Care Medicine, Sichuan Academy of Medical Science and Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Jun Liu
- Wenjiang District People’s Hospital of Chengdu, Chengdu, China
- Department of Ultrasound Medicine, Sichuan Academy of Medical Science and Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
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Xia Z, Hu M, Zheng L, Zheng E, Deng M, Wu J, Sheng X. Assessing whether serum ceruloplasmin promotes non-alcoholic steatohepatitis via regulating iron metabolism. J Med Biochem 2023; 42:113-121. [PMID: 36819130 PMCID: PMC9921090 DOI: 10.5937/jomb0-37597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 06/06/2022] [Indexed: 11/02/2022] Open
Abstract
Background Non-alcoholic steatohepatitis (NASH) is a progressive form of non-alcoholic fatty liver disease (NAFLD). The diagnostic gold standard for detecting NASH still relies upon an invasive pathological biopsy. There is, therefore, a need to identify non-invasive diagnostic markers. Oxidative stress mediates fatty liver progression to NASH. Imbalanced iron metabolism produces many reactive oxygen species (ROS). Ceruloplasmin is associated with oxidase and iron metabolism-related activities. The current study aimed to determine whether there was a correlation between ceruloplasmin levels and NASH and whether such a relationship may be associated with altered iron metabolism in NASH patients. Methods A total of 135 NAFLD patients were enrolled in this study. A pathological biopsy confirmed that 60 of those patients had NAFLD activity scores (NAS) 5, while the remaining 75 had NAS<5. Results Receiver operating characteristic (ROC) curves confirmed that serum ceruloplasmin and ferritin levels were predictors of NAS 5 and NAS<5, with area under the curve (AUC) values of 0.80 and 0.81, respectively. The serum ceruloplasmin levels in NAS 5 patients were significantly lower than those in NAS<5 patients (p< 0.001). Serum ceruloplasmin levels were also negatively correlated with ferritin levels. Lower serum ceruloplasmin levels were associated with more severe histopathological findings. Conclusions Low serum ceruloplasmin and high serum ferritin are correlated with NASH. A high concentration of serum ferritin is a viable clinical biomarker of NASH, and low serum ceruloplasmin may participate in the occurrence of NASH by regulating iron load, which can be used as a non-invasive diagnostic marker of NASH.
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Affiliation(s)
- Ziqiang Xia
- Wenzhou people's hospital, Department of Gastroenterology, Wenzhou, China
| | - Mei Hu
- Wenzhou people's hospital, Department of Gastroenterology, Wenzhou, China
| | - Liang Zheng
- Wenzhou people's hospital, Department of Gastroenterology, Wenzhou, China
| | - Endian Zheng
- Wenzhou people's hospital, Department of Gastroenterology, Wenzhou, China
| | - Min Deng
- The First Affiliated Hospital of Jiaxing College, Department of Infectious Diseases, Jiaxing, China
| | - Jinming Wu
- The First Affiliated Hospital of Wenzhou Medical University, Department of Gastroenterology, Wenzhou, China
| | - Xiong Sheng
- The First Affiliated Hospital of Jiaxing College, Department of Infectious Diseases, Jiaxing, China
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Liao W, Yang W, Shen Z, Ai W, Pan Q, Sun Y, Guo S. Heme Oxygenase-1 Regulates Ferrous Iron and Foxo1 in Control of Hepatic Gluconeogenesis. Diabetes 2021; 70:696-709. [PMID: 33408127 PMCID: PMC7897351 DOI: 10.2337/db20-0954] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 12/15/2020] [Indexed: 12/23/2022]
Abstract
The liver is a key player for maintaining glucose homeostasis. Excessive hepatic glucose production is considered to be a key for the onset of type 2 diabetes. The primary function of heme oxygenase-1 (HO1) is to catalyze the degradation of heme into biliverdin, ferrous iron, and carbon monoxide. Previous studies have demonstrated that the degradation of heme by HO1 in the liver results in mitochondrial dysfunction and drives insulin resistance. In this study, by overexpressing HO1 in hepatocytes and mice, we showed that HO1 promotes gluconeogenesis in a Foxo1-dependent manner. Importantly, HO1 overexpression increased the generation of ferrous iron in the liver, which further activates nuclear factor-κB and phosphorylates Foxo1 at Ser273 to enhance gluconeogenesis. We further assessed the role of HO1 in insulin-resistant liver-specific knockout of IRS1 and IRS2 genes (L-DKO) mice, which exhibit upregulation of HO1 in the liver and hepatic ferrous iron overload. HO1 knockdown by shRNA or treatment of iron chelator rescued the aberrant gluconeogenesis in L-DKO mice. In addition, we found that systemic iron overload promotes gluconeogenesis by activating the hepatic protein kinase A→Foxo1 axis. Thus, our results demonstrate the role of HO1 in regulating hepatic iron status and Foxo1 to control gluconeogenesis and blood glucose.
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Affiliation(s)
- Wang Liao
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX
| | - Wanbao Yang
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX
| | - Zheng Shen
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX
| | - Weiqi Ai
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX
| | - Quan Pan
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX
| | - Yuxiang Sun
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX
| | - Shaodong Guo
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX
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Yuan Q, Zhang Z, Hu X, Liao J, Kuang J. miR-374a/Myc axis modulates iron overload-induced production of ROS and the activation of hepatic stellate cells via TGF-β1 and IL-6. Biochem Biophys Res Commun 2019; 515:499-504. [PMID: 31171361 DOI: 10.1016/j.bbrc.2019.05.152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 05/24/2019] [Indexed: 01/06/2023]
Abstract
The transformation of hepatic stellate cells (HSCs) to activated myofibroblasts plays a critical role in the progression of hepatic fibrosis, while iron-catalyzed production of free radical, including reaction and active oxygen (ROS), and activation and transformation of HSC into a myofibroblasts has been regarded as a major mechanism. In the present study, we attempted to investigate the mechanism of iron overload in hepatic fibrosis from the perspective of regulating HSC activation via oxidative stress and miR-374a/Myc axis. FAC stimulation significantly increased ROS production and TGF-β1 and IL-6 release dose-dependently in hepatocytes. miR-374a could target Myc, a co-transcription factor of both TGF-β1 and IL-6, to negatively regulate Myc expression; FAC stimulation significantly suppressed miR-374a expression, whereas the suppressive effect of FAC stimulation on miR-374a expression could be reversed by ROS inhibitor NAC, indicating that miR-374a could be modulated by iron overload-induced ROS. Via targeting Myc, miR-374a overexpression significantly reduced FAC-induced increases in TGF-β1 and IL-6 levels within L02 cells, whereas the effects of miR-374a overexpression were significantly attenuated via Myc overexpression. Finally, miR-374a overexpression attenuated FAC-induced activity of HSCs by decreasing α-SMA and Collagen I levels whereas Myc overexpression enhanced FAC-induced activity of HSCs by increasing α-SMA and Collagen I levels; the effects of miR-374a overexpression could also be significantly reversed by Myc overexpression, indicating that miR-374a suppresses the activation of HSCs by inhibiting Myc to reduce FAC-induced increases in TGF-β1 and IL-6 release. In conclusion, we demonstrate a novel mechanism of miR-374a/Myc axis modulating iron overload-induced production of ROS and the activation of HSCs via TGF-β1 and IL-6.
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Affiliation(s)
- Qi Yuan
- Department of Hepatopathy, The Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, 410005, China
| | - Zheng Zhang
- Department of Hepatopathy, The Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, 410005, China.
| | - Xiaoxuan Hu
- Department of Hepatopathy, The Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, 410005, China
| | - Jinmao Liao
- Department of Hepatopathy, The Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, 410005, China
| | - Jia Kuang
- Department of Hepatopathy, The Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, 410005, China
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Tabei Y, Fukui H, Nishioka A, Hagiwara Y, Sato K, Yoneda T, Koyama T, Horie M. Effect of iron overload from multi walled carbon nanotubes on neutrophil-like differentiated HL-60 cells. Sci Rep 2019; 9:2224. [PMID: 30778158 PMCID: PMC6379482 DOI: 10.1038/s41598-019-38598-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 12/28/2018] [Indexed: 01/17/2023] Open
Abstract
Multi walled carbon nanotubes (MWCNTs) are one of the most intensively explored nanomaterials because of their unique physical and chemical properties. Due to the widespread use of MWCNTs, it is important to investigate their effects on human health. The precise mechanism of MWCNT toxicity has not been fully elucidated. The present study was designed to examine the mechanisms of MWCNT toxicity toward human promyelocytic leukemia HL-60 cells. First, we found that MWCNTs decreased the viability of neutrophil-like differentiated HL-60 cells but not undifferentiated HL-60 cells. Because neutrophil-like differentiated HL-60 cells exhibit enhanced phagocytic activity, the cytotoxicity of MWCNTs is dependent on the intracellularly localized MWCNTs. Next, we revealed that the cytotoxicity of MWCNTs is correlated with the intracellular accumulation of iron that is released from the engulfed MWCNTs in an acidic lysosomal environment. The intracellular accumulation of iron was repressed by treatment with cytochalasin D, a phagocytosis inhibitor. In addition, our results indicated that iron overload enhanced the release of interleukin-8 (IL-8), a chemokine that activates neutrophils, and subsequently elevated intracellular calcium concentration ([Ca2+]i). Finally, we found that the sustained [Ca2+]i elevation resulted in the loss of mitochondrial membrane potential and the increase of caspase-3 activity, thereby inducing apoptotic cell death. These findings suggest that the iron overload caused by engulfed MWCNTs results in the increase of IL-8 production and the elevation of [Ca2+]i, thereby activating the mitochondria-mediated apoptotic pathway.
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Affiliation(s)
- Yosuke Tabei
- Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2217-14 Hayashi-cho, Takamatsu, Kagawa, 761-0395, Japan.
| | - Hiroko Fukui
- Safety Evaluation Center, Showa Denko K.K., 1-1-1 Ohnodai, Midori-ku, Chiba-shi, Chiba, 267-0056, Japan
| | - Ayako Nishioka
- Safety Evaluation Center, Showa Denko K.K., 1-1-1 Ohnodai, Midori-ku, Chiba-shi, Chiba, 267-0056, Japan
| | - Yuji Hagiwara
- Safety Evaluation Center, Showa Denko K.K., 1-1-1 Ohnodai, Midori-ku, Chiba-shi, Chiba, 267-0056, Japan
| | - Kei Sato
- Safety Evaluation Center, Showa Denko K.K., 1-1-1 Ohnodai, Midori-ku, Chiba-shi, Chiba, 267-0056, Japan
| | - Tadashi Yoneda
- Safety Evaluation Center, Showa Denko K.K., 1-1-1 Ohnodai, Midori-ku, Chiba-shi, Chiba, 267-0056, Japan
| | - Tamami Koyama
- Institute for Advanced and Core Technology, Showa Denko K.K., 1-1-1 Ohnodai, Midori-ku, Chiba-shi, Chiba, 267-0056, Japan
| | - Masanori Horie
- Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2217-14 Hayashi-cho, Takamatsu, Kagawa, 761-0395, Japan
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Hubler MJ, Erikson KM, Kennedy AJ, Hasty AH. MFe hi adipose tissue macrophages compensate for tissue iron perturbations in mice. Am J Physiol Cell Physiol 2018; 315:C319-C329. [PMID: 29768045 DOI: 10.1152/ajpcell.00103.2018] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Resident adipose tissue macrophages (ATMs) play multiple roles to maintain tissue homeostasis, such as removing excess free fatty acids and regulation of the extracellular matrix. The phagocytic nature and oxidative resiliency of macrophages not only allows them to function as innate immune cells but also to respond to specific tissue needs, such as iron homeostasis. MFehi ATMs are a subtype of resident ATMs that we recently identified to have twice the intracellular iron content as other ATMs and elevated expression of iron-handling genes. Although studies have demonstrated that iron homeostasis is important for adipocyte health, little is known about how MFehi ATMs may respond to and influence adipose tissue iron availability. Two methodologies were used to address this question: dietary iron supplementation and intraperitoneal iron injection. Upon exposure to high dietary iron, MFehi ATMs accumulated excess iron, whereas the iron content of MFelo ATMs and adipocytes remained unchanged. In this model of chronic iron excess, MFehi ATMs exhibited increased expression of genes involved in iron storage. In the injection model, MFehi ATMs incorporated high levels of iron, and adipocytes were spared iron overload. This acute model of iron overload was associated with increased numbers of MFehi ATMs; 17% could be attributed to monocyte recruitment and 83% to MFelo ATM incorporation into the MFehi pool. The MFehi ATM population maintained its low inflammatory profile and iron-cycling expression profile. These studies expand the field's understanding of ATMs and confirm that they can respond as a tissue iron sink in models of iron overload.
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Affiliation(s)
- Merla J Hubler
- Department of Molecular Physiology and Biophysics, School of Medicine, Vanderbilt University , Nashville, Tennessee
| | - Keith M Erikson
- Department of Nutrition, University of North Carolina at Greensboro , Greensboro, North Carolina
| | - Arion J Kennedy
- Department of Molecular Physiology and Biophysics, School of Medicine, Vanderbilt University , Nashville, Tennessee
| | - Alyssa H Hasty
- Department of Molecular Physiology and Biophysics, School of Medicine, Vanderbilt University , Nashville, Tennessee.,VA Tennessee Valley Healthcare System, Nashville, Tennessee
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Dietary Iron Supplementation Alters Hepatic Inflammation in a Rat Model of Nonalcoholic Steatohepatitis. Nutrients 2018; 10:nu10020175. [PMID: 29401710 PMCID: PMC5852751 DOI: 10.3390/nu10020175] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 01/31/2018] [Accepted: 02/01/2018] [Indexed: 02/06/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is now the most common liver disease in the world. NAFLD can progress to nonalcoholic steatohepatitis (NASH), cirrhosis and eventually hepatocellular carcinoma. Acquired hepatic iron overload is seen in a number of patients with NAFLD; however, its significance in the pathology of NAFLD is still debated. Here, we investigated the role of dietary iron supplementation in experimental steatohepatitis in rats. Rats were fed a control, high-fat (HF), high-fat high-iron (HFHI) and high-iron (HI) diet for 30 weeks. Blood biochemical, histopathological and gut microbiota analyses were performed. Rats in HF and HFHI groups showed an ALT-dominant elevation of serum transaminases, hepatic steatosis, hepatic inflammation, and upregulation of proinflammatory cytokines. The number of large inflammatory foci, corresponding to lobular inflammation in NASH patients, was significantly higher in HFHI than in HF group; within the lesion, macrophages with intense iron staining were observed. Hepatic expression of TNFα was higher in HFHI than that in HF group. There was no significant change in hepatic oxidative stress, gut microbiota or serum endotoxin levels between HF and HFHI groups. These results suggested that dietary iron supplementation enhances experimental steatohepatitis induced by long-term high-fat diet feeding in rats. Iron-laden macrophages can play an important role in the enhancement of hepatic inflammation.
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Narula N, Narula N, Ahmadi A. Microvascular Integrity in Myocardial Injury: The Irony of Iron Deposition. Circ Cardiovasc Imaging 2016; 9:CIRCIMAGING.116.005821. [PMID: 27903549 DOI: 10.1161/circimaging.116.005821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Navneet Narula
- From the Department of Pathology, Weill Cornell College of Medicine, New York, NY (Navneet Narula); Michael A. and Zena Wiener Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, NY (Nupoor Narula, A.A.).
| | - Nupoor Narula
- From the Department of Pathology, Weill Cornell College of Medicine, New York, NY (Navneet Narula); Michael A. and Zena Wiener Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, NY (Nupoor Narula, A.A.)
| | - Amir Ahmadi
- From the Department of Pathology, Weill Cornell College of Medicine, New York, NY (Navneet Narula); Michael A. and Zena Wiener Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, NY (Nupoor Narula, A.A.)
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Hagström H, Nasr P, Bottai M, Ekstedt M, Kechagias S, Hultcrantz R, Stål P. Elevated serum ferritin is associated with increased mortality in non-alcoholic fatty liver disease after 16 years of follow-up. Liver Int 2016; 36:1688-1695. [PMID: 27064133 DOI: 10.1111/liv.13144] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 04/07/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS High levels of ferritin in patients with non-alcoholic fatty liver disease (NAFLD) are associated with significant fibrosis and higher NAFLD activity score (NAS). It is unclear if this association has an impact on mortality. We investigated if high levels of ferritin, with or without iron overload, were associated with an increased mortality in NAFLD. METHODS We included 222 patients between 1979 and 2009 with biopsy-proven NAFLD and available serum ferritin concentrations. The cohort was divided into 'high' (n = 89) and 'normal' (n = 133) ferritin values, using a cut-point of 350 μg/L in males, and 150 μg/L in females, and stratified upon iron overload status. Data on mortality were obtained from a national, population-based register. Poisson regression was used to estimate hazard ratios for mortality. The estimates were adjusted for age at biopsy, sex, smoking, BMI, diabetes, hypertension, cardiovascular disease and fibrosis stage at the time of biopsy. RESULTS The median follow-up time was 15.6 years (range: 0.5-34.2). Patients with high ferritin had more advanced fibrosis and higher NAS than patients with normal ferritin (P < 0.05). Fifteen years after diagnosis, and after adjusting for confounders, the high-ferritin group showed an increasingly higher mortality that was statistically significant (Hazard ratio = 1.10 per year, 95% Confidence interval 1.01-1.21, P < 0.05). There was no difference in mortality between patients with different iron overload patterns. CONCLUSIONS High levels of ferritin are associated with a long-term increased risk of death.
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Affiliation(s)
- Hannes Hagström
- Center for Digestive Diseases, Unit of Hepatology, Karolinska University Hospital, Stockholm, Sweden. .,Department of Medicine, Huddinge, Karolinska Institutet, Stockholm, Sweden.
| | - Patrik Nasr
- Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Matteo Bottai
- Unit of Biostatistics, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Mattias Ekstedt
- Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Stergios Kechagias
- Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Rolf Hultcrantz
- Center for Digestive Diseases, Unit of Hepatology, Karolinska University Hospital, Stockholm, Sweden.,Department of Medicine, Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Per Stål
- Center for Digestive Diseases, Unit of Hepatology, Karolinska University Hospital, Stockholm, Sweden.,Department of Medicine, Huddinge, Karolinska Institutet, Stockholm, Sweden
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The detrimental effects of iron on the joint: a comparison between haemochromatosis and haemophilia. J Clin Pathol 2015; 68:592-600. [DOI: 10.1136/jclinpath-2015-202967] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 03/29/2015] [Indexed: 12/21/2022]
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Iron overload-modulated nuclear factor kappa-B activation in human endometrial stromal cells as a mechanism postulated in endometriosis pathogenesis. Fertil Steril 2014; 103:439-47. [PMID: 25500022 DOI: 10.1016/j.fertnstert.2014.10.046] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 10/19/2014] [Accepted: 10/24/2014] [Indexed: 12/27/2022]
Abstract
OBJECTIVE To evaluate the effect of iron overload on nuclear factor kappa-B (NF-κB) activation in human endometrial stromal cells (ESCs). DESIGN Experimental study. SETTING University hospital research laboratory. PATIENT(S) Ten healthy women. INTERVENTION(S) Isolated ESCs from endometrial biopsies were incubated with 50 μM FeSO(4) or vehicle. The NF-κB inhibitor [5-(p-fluorophenyl)-2-ureido] thiophene-3-carboxamide (TPCA-1), which inhibits IKKβ, the kinase of IκBα (inhibitory protein of NF-κB), was used to prevent iron overload-stimulated NF-κB changes in ESCs. MAIN OUTCOME MEASURE(S) NF-κB activation was assessed by p65:DNA-binding activity immunodetection assay. IκBα, p65, and intercellular adhesion molecule (ICAM)-1 proteins expression was evaluated by Western blots. ESC soluble ICAM (sICAM)-1 secretion was measured by ELISA using conditioned medium. RESULT(S) Iron overload increased p65:DNA-binding activity and decreased IκBα and p65 cytoplasmic expression in ESCs after 30 minutes of incubation as compared with the basal condition. ESC ICAM-1 expression and sICAM-1 secretion were higher after 24 hours of iron overload treatment than in the absence of treatment. TPCA-1 prevented the iron overload-induced increase of p65:DNA binding and IκBα degradation. CONCLUSION(S) Iron overload activates IKKβ in ESCs, stimulating the NF-κB pathway and increasing ICAM-1 expression and sICAM-1 secretion. These results suggest that iron overload induces a proendometriotic phenotype on healthy ESCs, which could participate in endometriosis pathogenesis and development.
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Abstract
Iron is an essential nutrient that facilitates cell proliferation and growth. However, iron also has the capacity to engage in redox cycling and free radical formation. Therefore, iron can contribute to both tumour initiation and tumour growth; recent work has also shown that iron has a role in the tumour microenvironment and in metastasis. Pathways of iron acquisition, efflux, storage and regulation are all perturbed in cancer, suggesting that reprogramming of iron metabolism is a central aspect of tumour cell survival. Signalling through hypoxia-inducible factor (HIF) and WNT pathways may contribute to altered iron metabolism in cancer. Targeting iron metabolic pathways may provide new tools for cancer prognosis and therapy.
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Affiliation(s)
- Suzy V Torti
- Departments of Molecular, Microbial and Structural Biology, University of Connecticut Health Center, Farmington, Connecticut 06030, USA.
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15
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Maliken BD, Nelson JE, Klintworth HM, Beauchamp M, Yeh MM, Kowdley KV. Hepatic reticuloendothelial system cell iron deposition is associated with increased apoptosis in nonalcoholic fatty liver disease. Hepatology 2013; 57:1806-13. [PMID: 23325576 PMCID: PMC3637923 DOI: 10.1002/hep.26238] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Revised: 11/21/2012] [Accepted: 11/26/2012] [Indexed: 02/06/2023]
Abstract
UNLABELLED The aim of this study was to examine the relationship between the presence of hepatic iron deposition, apoptosis, histologic features, and serum markers of oxidative stress (OS) and cell death in nonalcoholic fatty liver disease (NAFLD). Clinical, biochemical, metabolic, and independent histopathologic assessment was conducted in 83 unselected patients with biopsy-proven NAFLD from a single center. Apoptosis and necrosis in serum was quantified using serum cytokeratin 18 (CK18) M30 and M65 enzyme-linked immunosorbent assays and in liver by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining in situ. Serum malondialdehyde (MDA) and thioredoxin-1 (Trx1) levels were measured to evaluate OS. Presence of reticuloendothelial system (RES) cell iron in the liver was associated with nonalcoholic steatohepatitis (P < 0.05) and increased hepatic TUNEL staining (P = 0.02), as well as increased serum levels of apoptosis-specific (M30; P = 0.013) and total (M65; P = 0.006) CK18 fragments, higher MDA (P = 0.002) and lower antioxidant Trx1 levels (P = 0.012), compared to patients without stainable hepatic iron. NAFLD patients with a hepatocellular (HC) iron staining pattern also had increased serum MDA (P = 0.006), but not M30 CK18 levels or TUNEL staining, compared to subjects without stainable hepatic iron. Patients with iron deposition limited to hepatocytes had a lower proportion of apoptosis-specific M30 fragments relative to total M65 CK18 levels (37% versus ≤25%; P < 0.05). CONCLUSIONS Presence of iron in liver RES cells is associated with NASH, increased apoptosis, and increased OS. HC iron deposition in NAFLD is also associated with OS and may promote hepatocyte necrosis in this disease.
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Affiliation(s)
- Bryan D. Maliken
- Center for Liver Disease, Digestive Disease Institute and Benaroya Research Institute, Virginia Mason Medical Center, Seattle, WA, USA
| | - James E. Nelson
- Center for Liver Disease, Digestive Disease Institute and Benaroya Research Institute, Virginia Mason Medical Center, Seattle, WA, USA
| | - Heather M. Klintworth
- Center for Liver Disease, Digestive Disease Institute and Benaroya Research Institute, Virginia Mason Medical Center, Seattle, WA, USA
| | - Mary Beauchamp
- Benaroya Research Institute, Virginia Mason Medical Center, Seattle, WA, USA
| | - Matthew M. Yeh
- University of Washington Medical Center, Seattle, WA, USA
| | - Kris V. Kowdley
- Center for Liver Disease, Digestive Disease Institute and Benaroya Research Institute, Virginia Mason Medical Center, Seattle, WA, USA,University of Washington Medical Center, Seattle, WA, USA
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16
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Liver hepcidin mRNA expression is inappropriately low in alcoholic patients compared with healthy controls. Eur J Gastroenterol Hepatol 2012; 24:1158-65. [PMID: 22732356 DOI: 10.1097/meg.0b013e328355cfd0] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Hepcidin plays a crucial role in iron metabolism, preventing its absorption at the basolateral enterocyte membrane. Hepcidin regulation is complex and regulated at the transcriptional level. The relation between iron overload and alcoholic liver disease is well known, but its mechanism is not clear. We present an observational, case-control study, aimed at evaluating the effects of alcohol on the expression of hepcidin in human participants. We intended to assess whether iron overload related to alcohol ingestion was caused by hepcidin-impaired expression by determining hepcidin mRNA expression and relating it to iron stores, both in alcoholic patients and in normal controls. METHODS We compared liver hepcidin mRNA expression between 25 active drinkers with alcoholic liver disease, without cirrhosis, and 20 healthy controls. All individuals were evaluated for HFE mutations, complete blood count, coagulation, glucose, kidney function, liver function, viral hepatitis, C-reactive protein, interleukin 6, tumor necrosis factor α, and serum iron, ferritin, and transferrin saturation. Total RNA was isolated from liver samples, cDNA was obtained by reverse transcription, and hepatic expression levels of hepcidin were determined by real-time PCR using the comparative Ct method (2(-ΔΔCt)). RESULTS Serum ferritin and transferrin saturation were significantly higher in patients. Hepcidin was downregulated in patients compared with the controls by a mean factor of -0.44 (log10 2(-ΔΔCt)) (P=0.009). Hepcidin expression was not significantly different between the several grades of fibrosis, necroinflammatory activity, and liver iron stores. Heavy alcohol consumption caused the highest hepcidin mRNA suppression. The hepcidin mRNA expression/serum ferritin ratio was significantly lower in alcoholic patients (P<0.0001). CONCLUSION Hepcidin liver expression is inappropriately low in alcoholic patients with active alcoholism and preserved hepatic function, and we conclude that this is the mechanism for alcohol consumption-associated iron overload in humans.
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Abstract
Non-Alcoholic Fatty Liver Disease (NAFLD) is a common worldwide clinical and major public health problem affecting both adults and children in developed nations. Increased hepatic iron stores are observed in about one-third of adult NAFLD patients. Iron deposition may occur in parenchymal and/or non-parenchymal cells of the reticuloendothelial system (RES). Similar patterns of iron deposition have been associated with increased severity of other chronic liver diseases including HCV infection and dysmetabolic iron overload, suggesting there may be a common mechanism for hepatic iron deposition in these diseases. In NAFLD, iron may potentiate the onset and progression of disease by increasing oxidative stress and altering insulin signaling and lipid metabolism. The impact of iron in these processes may depend upon the sub-cellular location of iron deposition in hepatocytes or RES cells. Iron depletion therapy has shown efficacy at reducing serum aminotransferase levels and improving insulin sensitivity in subjects with NAFLD.
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Abstract
Iron and its homeostasis are intimately tied to the inflammatory response. The adaptation to iron deficiency, which confers resistance to infection and improves the inflammatory condition, underlies what is probably the most obvious link: the anemia of inflammation or chronic disease. A large number of stimulatory inputs must be integrated to tightly control iron homeostasis during the inflammatory response. In order to understand the pathways of iron trafficking and how they are regulated, this article presents a brief overview of iron homeostasis. A major focus is on the regulation of the peptide hormone hepcidin during the inflammatory response and how its function contributes to the process of iron withdrawal. The review also summarizes new and emerging information about other iron metabolic regulators and effectors that contribute to the inflammatory response. Potential benefits of treatment to ameliorate the hypoferremic condition promoted by inflammation are also considered.
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Affiliation(s)
- Marianne Wessling-Resnick
- Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
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Shaw CA, Robertson S, Miller MR, Duffin R, Tabor CM, Donaldson K, Newby DE, Hadoke PWF. Diesel exhaust particulate--exposed macrophages cause marked endothelial cell activation. Am J Respir Cell Mol Biol 2010; 44:840-51. [PMID: 20693402 DOI: 10.1165/rcmb.2010-0011oc] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Exposure to air pollution containing diesel exhaust particulate (DEP) is linked to adverse cardiovascular events. This study tested the hypothesis that DEP not only causes direct endothelial cell injury, but also induces indirect endothelial cell activation via the release of soluble proinflammatory cytokines from macrophages. Human umbilical vein endothelial cells (HUVECs) and monocyte-derived macrophages (MDMs) were incubated with DEP (1-100 μg/ml; 24 h). Supernatants were analyzed for monocyte chemotactic protein (MCP)-1, IL6, IL8, and TNF-α. Indirect actions of DEP were investigated by incubating HUVECs with conditioned media from DEP-exposed MDMs in the presence and absence of the TNF-α inhibitor, etanercept. A modified Boyden chamber assay was used to determine whether HUVECs treated in this manner induced monocyte chemotaxis. Direct incubation with DEP induced a modest increase in MCP-1 concentration, but had no effect on IL-6 or IL-8 release from HUVECs. In contrast, direct treatment of MDMs with DEP had no effect on MCP-1, but elevated IL-8 and TNF-α concentrations. Incubation with conditioned media from DEP-exposed MDMs caused a dramatic amplification in MCP-1 and IL-6, but not IL-8, release from HUVECs. The potentiation of HUVEC activation was suppressed by TNF-α inhibition. MCP-1- and IL-6-containing HUVEC supernatants caused increased monocyte chemotaxis that was not inhibited by anti-MCP-1 antibodies. We conclude that DEP has only modest direct endothelial effects. In contrast, proinflammatory cytokines released from particle-laden MDMs appear to exacerbate endothelial activation after DEP exposure.
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Affiliation(s)
- Catherine A Shaw
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, Scotland, UK.
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20
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Messa E, Carturan S, Maffè C, Pautasso M, Bracco E, Roetto A, Messa F, Arruga F, Defilippi I, Rosso V, Zanone C, Rotolo A, Greco E, Pellegrino RM, Alberti D, Saglio G, Cilloni D. Deferasirox is a powerful NF-kappaB inhibitor in myelodysplastic cells and in leukemia cell lines acting independently from cell iron deprivation by chelation and reactive oxygen species scavenging. Haematologica 2010; 95:1308-16. [PMID: 20534700 PMCID: PMC2913079 DOI: 10.3324/haematol.2009.016824] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Revised: 01/27/2010] [Accepted: 01/28/2010] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Usefulness of iron chelation therapy in myelodysplastic patients is still under debate but many authors suggest its possible role in improving survival of low-risk myelodysplastic patients. Several reports have described an unexpected effect of iron chelators, such as an improvement in hemoglobin levels, in patients affected by myelodysplastic syndromes. Furthermore, the novel chelator deferasirox induces a similar improvement more rapidly. Nuclear factor-kappaB is a key regulator of many cellular processes and its impaired activity has been described in different myeloid malignancies including myelodysplastic syndromes. DESIGN AND METHODS We evaluated deferasirox activity on nuclear factor-kappaB in myelodysplastic syndromes as a possible mechanism involved in hemoglobin improvement during in vivo treatment. Forty peripheral blood samples collected from myelodysplastic syndrome patients were incubated with 50 muM deferasirox for 18h. RESULTS Nuclear factor-kappaB activity dramatically decreased in samples showing high basal activity as well as in cell lines, whereas no similar behavior was observed with other iron chelators despite a similar reduction in reactive oxygen species levels. Additionally, ferric hydroxyquinoline incubation did not decrease deferasirox activity in K562 cells suggesting the mechanism of action of the drug is independent from cell iron deprivation by chelation. Finally, incubation with both etoposide and deferasirox induced an increase in K562 apoptotic rate. CONCLUSIONS Nuclear factor-kappaB inhibition by deferasirox is not seen from other chelators and is iron and reactive oxygen species scavenging independent. This could explain the hemoglobin improvement after in vivo treatment, such that our hypothesis needs to be validated in further prospective studies.
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Affiliation(s)
- Emanuela Messa
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Sonia Carturan
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Chiara Maffè
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Marisa Pautasso
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Enrico Bracco
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Antonella Roetto
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Francesca Messa
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Francesca Arruga
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Ilaria Defilippi
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Valentina Rosso
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Chiara Zanone
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Antonia Rotolo
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Elisabetta Greco
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Rosa M. Pellegrino
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | | | - Giuseppe Saglio
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
| | - Daniela Cilloni
- Division of Hematology and Internal Medicine, Department of Clinical and Biological Sciences of the University of Turin, Turin, Italy and
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21
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Uchiyama A, Kim JS, Kon K, Jaeschke H, Ikejima K, Watanabe S, Lemasters JJ. Translocation of iron from lysosomes into mitochondria is a key event during oxidative stress-induced hepatocellular injury. Hepatology 2008; 48:1644-54. [PMID: 18846543 PMCID: PMC2579320 DOI: 10.1002/hep.22498] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
UNLABELLED Iron overload exacerbates various liver diseases. In hepatocytes, a portion of non-heme iron is sequestered in lysosomes and endosomes. The precise mechanisms by which lysosomal iron participates in hepatocellular injury remain uncertain. Here, our aim was to determine the role of intracellular movement of chelatable iron in oxidative stress-induced killing to cultured hepatocytes from C3Heb mice and Sprague-Dawley rats. Mitochondrial polarization and chelatable iron were visualized by confocal microscopy of tetramethylrhodamine methylester (TMRM) and quenching of calcein, respectively. Cell viability and hydroperoxide formation (a measure of lipid peroxidation) were measured fluorometrically using propidium iodide and chloromethyl dihydrodichlorofluorescein, respectively. After collapse of lysosomal/endosomal acidic pH gradients with bafilomycin (50 nM), an inhibitor of the vacuolar proton-pumping adenosine triphosphatase, cytosolic calcein fluorescence became quenched. Deferoxamine mesylate and starch-deferoxamine (1 mM) prevented bafilomycin-induced calcein quenching, indicating that bafilomycin induced release of chelatable iron from lysosomes/endosomes. Bafilomycin also quenched calcein fluorescence in mitochondria, which was blocked by 20 microM Ru360, an inhibitor of the mitochondrial calcium uniporter, consistent with mitochondrial iron uptake by the uniporter. Bafilomycin alone was not sufficient to induce mitochondrial depolarization and cell killing, but in the presence of low-dose tert-butylhydroperoxide (25 microM), bafilomycin enhanced hydroperoxide generation, leading to mitochondrial depolarization and subsequent cell death. CONCLUSION Taken together, the results are consistent with the conclusion that bafilomycin induces release of chelatable iron from lysosomes/endosomes, which is taken up by mitochondria. Oxidative stress and chelatable iron thus act as two "hits" synergistically promoting toxic radical formation, mitochondrial dysfunction, and cell death. This pathway of intracellular iron translocation is a potential therapeutic target against oxidative stress-mediated hepatotoxicity.
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Affiliation(s)
- Akira Uchiyama
- Department of Pharmaceutical & Biomedical Sciences, Medical University of South Carolina, Charleston, SC, USA,Department of Gastroenterology, Juntendo University School of Medicine, Tokyo, Japan
| | - Jae-Sung Kim
- Department of Surgery, University of Florida, Gainesville, FL, USA
| | - Kazuyoshi Kon
- Department of Gastroenterology, Juntendo University School of Medicine, Tokyo, Japan
| | - Hartmut Jaeschke
- Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, Kansas
| | - Kenichi Ikejima
- Department of Gastroenterology, Juntendo University School of Medicine, Tokyo, Japan
| | - Sumio Watanabe
- Department of Gastroenterology, Juntendo University School of Medicine, Tokyo, Japan
| | - John J. Lemasters
- Department of Pharmaceutical & Biomedical Sciences, Medical University of South Carolina, Charleston, SC, USA,Department of Biochemistry & Molecular Biology, Medical University of South Carolina, Charleston, SC, USA
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22
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Zager RA. Parenteral iron compounds: potent oxidants but mainstays of anemia management in chronic renal disease. Clin J Am Soc Nephrol 2007; 1 Suppl 1:S24-31. [PMID: 17699373 DOI: 10.2215/cjn.01410406] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Ferric iron (Fe)-carbohydrate complexes are widely used for treating Fe deficiency in patients who are unable to meet their Fe requirements with oral supplements. Intravenous Fe generally is well tolerated and effective in correcting Fe-deficient states. However, the complexing of Fe to carbohydrate polymers does not block its potent pro-oxidant effects; systemic free radical generation and, possibly, tissue damage may result. The purpose of this review is to (1) underscore the capacity of currently used parenteral Fe formulations to induce oxidative stress, (2) compare the severity of these oxidant reactions with those that result from unshielded Fe salts and with each other, and (3) speculate as to the potential of these agents to induce acute renal cell injury and augment systemic inflammatory responses. The experimental data that are reviewed should not be extrapolated to the clinical setting or be used for clinical decision making. Rather, it is hoped that the information provided herein may have utility for clinical hypothesis generation and, hence, future clinical studies. By so doing, a better understanding of Fe's potential protean effects on patients with renal disease may result.
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MESH Headings
- Acute Kidney Injury/chemically induced
- Acute Kidney Injury/metabolism
- Adenosine Triphosphate/metabolism
- Anemia, Iron-Deficiency/drug therapy
- Anemia, Iron-Deficiency/etiology
- Anemia, Iron-Deficiency/metabolism
- Animals
- Endothelial Cells/drug effects
- Endothelial Cells/metabolism
- Ferric Compounds/toxicity
- Ferric Oxide, Saccharated
- Glucaric Acid
- Hematinics/administration & dosage
- Hematinics/toxicity
- Humans
- Inflammation/chemically induced
- Inflammation/metabolism
- Infusions, Intravenous
- Iron Compounds/administration & dosage
- Iron Compounds/toxicity
- Iron-Dextran Complex/toxicity
- Kidney Cortex/drug effects
- Kidney Cortex/metabolism
- Kidney Tubules, Proximal/drug effects
- Kidney Tubules, Proximal/metabolism
- Lipid Peroxidation/drug effects
- Mitochondria/drug effects
- Mitochondria/metabolism
- Oxidative Stress/drug effects
- Renal Dialysis
- Renal Insufficiency, Chronic/complications
- Renal Insufficiency, Chronic/drug therapy
- Renal Insufficiency, Chronic/metabolism
- Renal Insufficiency, Chronic/therapy
- Tumor Necrosis Factor-alpha/metabolism
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Affiliation(s)
- Richard A Zager
- Fred Hutchinson Cancer Research Center, Department of Medicine, University of Washington, Seattle, Washington 98109, USA.
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Hoffman M, Harger A, Lenkowski A, Hedner U, Roberts HR, Monroe DM. Cutaneous wound healing is impaired in hemophilia B. Blood 2006; 108:3053-60. [PMID: 16825491 DOI: 10.1182/blood-2006-05-020495] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Abstract
We used a mouse model to test the hypothesis that the time course and histology of wound healing is altered in hemophilia B. Punch biopsies (3 mm) were placed in the skin of normal mice and mice with hemophilia. The size of the wounds was measured daily until the epidermal defect closed. All wounds closed in mice with hemophilia by 12 days, compared with 10 days in normal animals. Skin from the area of the wound was harvested at different time points and examined histologically. Hemophilic animals developed subcutaneous hematomas; normal animals did not. Macrophage infiltration was significantly delayed in hemophilia B. Unexpectedly, hemophilic mice developed twice as many blood vessels in the healing wounds as controls, and the increased vascularity persisted for at least 2 weeks. The deposition and persistence of ferric iron was also greater in hemophilic mice. We hypothesize that iron plays a role in promoting excess angiogenesis after wounding as it had been proposed to do in hemophilic arthropathy. We have demonstrated that impaired coagulation leads to delayed wound healing with abnormal histology. Our findings have significant implications for treatment of patients with hemophilia, and also highlight the importance of rapidly establishing hemostasis following trauma or surgery.
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Affiliation(s)
- Maureane Hoffman
- Laboratory Service (113), Durham Veterans Affairs Medical Center, 508 Fulton St, Durham, NC 27705, USA.
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Zager RA, Johnson ACM, Hanson SY, Lund S. Parenteral iron compounds sensitize mice to injury-initiated TNF-alpha mRNA production and TNF-alpha release. Am J Physiol Renal Physiol 2004; 288:F290-7. [PMID: 15494544 DOI: 10.1152/ajprenal.00342.2004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Intravenous Fe is widely used to treat anemia in renal disease patients. However, concerns of potential Fe toxicity exist. To more fully define its spectrum, this study tested Fe's impact on systemic inflammation following either endotoxemia or the induction of direct tissue damage (glycerol-mediated rhabdomyolysis). The inflammatory response was gauged by tissue TNF-alpha message expression and plasma TNF-alpha levels. CD-1 mice received either intravenous Fe sucrose, -gluconate, or -dextran (FeS, FeG, or FeD, respectively; 2 mg), followed by either endotoxin (LPS) or glycerol injection 0-48 h later. Plasma TNF-alpha was assessed by ELISA 2-3 h after the LPS or glycerol challenge. TNF-alpha mRNA expression (RT-PCR) was measured in the kidney, heart, liver, lung, and spleen with Fe +/- LPS treatment. Finally, the relative impacts of intramuscular vs. intravenous Fe and of glutathione (GSH) on Fe/LPS- induced TNF-alpha generation were assessed. Each Fe preparation significantly enhanced LPS- or muscle injury-mediated TNF-alpha generation. This effect was observed for at least 48 h post-Fe injection, a time at which plasma iron levels were increased by levels insufficient to fully saturate transferrin. Fe did not independently increase plasma TNF-alpha or tissue mRNA. However, it potentiated postinjury-induced TNF-alpha mRNA increments and did so in an organ-specific fashion (kidney, heart, and lung; but not in liver or spleen). Intramuscular administration, but not GSH treatment, negated Fe's ability to synergize LPS-mediated TNF-alpha release. We conclude 1) intravenous Fe can enhance TNF-alpha generation during LPS- or glycerol-induced tissue damage; 2) increased TNF-alpha gene transcription in the kidney, heart, and lung may contribute to this result; and 3) intramuscular administration, but not GSH, might potentially mitigate some of Fe's systemic toxic effects.
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Sacca P, Caballero F, Batlle A, Vazquez E. Cell cycle arrest and modulation of HO-1 expression induced by acetyl salicylic acid in hepatocarcinogenesis. Int J Biochem Cell Biol 2004; 36:1945-53. [PMID: 15203109 DOI: 10.1016/j.biocel.2004.01.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2003] [Revised: 01/28/2004] [Accepted: 01/29/2004] [Indexed: 12/28/2022]
Abstract
BACKGROUND AND AIMS Control of cell proliferation is important for cancer prevention since cell proliferation has an essential role in carcinogenesis. In rodent carcinogenesis models, antioxidant agents suppress carcinogen-induced cellular hyper proliferation in the target organs. Strict control of cell division is an essential process to ensure that DNA synthesis and mitotic division are accurately and coordinately executed. We studied the interplay between cell cycle and heme oxygenase-1 (HO-1) and the effect of the acetylsalicylic acid (ASA) in hepatic carcinogenesis. METHODS Male CF1 mice pre-treated with dietary p-dimethylaminoazobenzene (DAB; 0.5%, w/w) were fed with ASA (0.16%, w/w). We investigated the hepatic expression of cyclin D1, cyclin E, Cdk2, Cdk4, p21, p27, p53; the level of bcl-2, an antiapoptotic protein and of heme oxygenase-1 (HO-1), a marker of oxidative stress, by Western blot analysis. RESULTS The treatment with ASA produced an important attenuation in the induction of cyclin E and cyclin D1 provoked by DAB. p21 and p27 levels were increased when animals received both drugs. The administration of ASA to DAB treated animals induced Cdk2 (29%). HO-1 induction (65%) provoked by DAB was diminished by ASA administration reaching lower induction levels (23%). CONCLUSION The deregulation of cyclin/CDK expression and the up-regulation of p21 and p27 with the administration of ASA, post-treatment of the carcinogen administration, would block the pass through out to the G0/G1 check point to permit the cells to repair their DNA and HO-1 protected the liver from reactive oxygen species produced from DAB.
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Affiliation(s)
- P Sacca
- Departamento Química Biológica, Facultad de Ciencias Exactas y Naturales, Centro de Investigaciones sobre Porfirinas y Porfirias (CIPYP), CONICET, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón II, 2do Piso, C1428EHA Buenos Aires, Argentina
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Harhaji L, Vuckovic O, Miljkovic D, Stosic-Grujicic S, Trajkovic V. Iron down-regulates macrophage anti-tumour activity by blocking nitric oxide production. Clin Exp Immunol 2004; 137:109-16. [PMID: 15196250 PMCID: PMC1809097 DOI: 10.1111/j.1365-2249.2004.02515.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Although the inhibitory effect of iron on macrophage production of tumoricidal free radical nitric oxide (NO) has been reported, its possible influence on macrophage anti-tumour activity has not been established. In the present study, FeSO4 markedly reduced IFN-gamma + LPS-induced NO synthesis in mouse and rat macrophages. The effect of iron coincided with the loss of macrophage cytotoxic activity against NO-sensitive C6 rat astrocytoma and L929 mouse fibrosarcoma cell lines, as measured by MTT assay for cellular respiration and the crystal violet test for cell viability. Tumour cell survival did not improve further in the presence of FeSO4 if macrophage NO release and cytotoxicity were already blocked by aminoguanidine. In accordance with the results obtained with exogenous iron, cell membrane permeable iron chelator o-phenanthroline enhanced both macrophage NO release and anti-tumour activity. Iron also down-regulated NO production and increased the viability of L929 fibrosarcoma cells stimulated with IFN-gamma + LPS in the absence of macrophages. However, neither NO release nor cell viability was affected by iron addition to cultures of the C6 astrocytoma cell line. Iron was unable to prevent L929 and C6 cell death induced by the NO releasing chemicals SNP and SIN-1, indicating that iron-mediated inhibition of NO synthesis, rather than interference with its cytotoxic action, was responsible for the protection of tumour cells. Collectively, these results indicate that iron might protect tumour cells by reducing both macrophage and tumour cell-derived NO release.
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Affiliation(s)
- L Harhaji
- Department of Neurobiology and Immunology, Institute for Biological Research, University of Belgrade, Belgrade, Serbia and Montenegro.
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Xu GF, Wang XY, Ge GL, Li PT, Jia X, Tian DL, Jiang LD, Yang JX. Dynamic changes of capillarization and peri-sinusoid fibrosis in alcoholic liver diseases. World J Gastroenterol 2004; 10:238-43. [PMID: 14716831 PMCID: PMC4717012 DOI: 10.3748/wjg.v10.i2.238] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
AIM: To investigate the dynamic changes of capillarization and peri-sinusoid fibrosis in an alcoholic liver disease model induced by a new method.
METHODS: Male SD rats were randomly divided into 6 groups, namely normal, 4 d, 2 w, 4 w, 9 w and 11 w groups. The animals were fed with a mixture of alcohol for designated days and then decollated, and their livers were harvested to examine the pathological changes of hepatocytes, hepatic stellate cells, sinusoidal endothelial cells, sinusoid, peri-sinusoid. The generation of three kinds of extra cellular matrix was also observed.
RESULTS: The injury of hepatocytes became severer as modeling going on. Under electronic microscope, fatty vesicles and swollen mitochondria in hepatocytes, activated hepatic stellate cells with fibrils could been seen near or around it. Fenestrae of sinusoidal endothelial cells were decreased or disappeared, sinusoidal basement was formed. Under light microscopy typical peri-sinusoid fibrosis, gridding-like fibrosis, broaden portal areas, hepatocyte’s fatty and balloon denaturation, iron sediment, dot necrosis, congregated lymphatic cells and leukocytes were observed. Type I collagen showed an increasing trend as modeling going on, slightly recovered when modeling stopped for 2 weeks. Meanwhile, type IV collagen decreased rapidly when modeling began and recovered after modeling stopped for 2 weeks. Laminin increased as soon as modeling began and did not recover when modeling stopped for 2 weeks.
CONCLUSION: The pathological changes of the model were similar to that of human ALD, but mild in degree. It had typical peri-sinusoid fibrosis, however, capillarization seemed to be instable. It may be related with the reduction of type IV collagen in the basement of sinusoid during modeling.
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Affiliation(s)
- Guang-Fu Xu
- Digestive Department of the Affiliated Dongzhimen Hospital, Beijing University of Traditional Chinese Medicine, Beijing 100700, China.
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Yang T, Brittenham GM, Dong WQ, Levy MN, Obejero-Paz CA, Kuryshev YA, Brown AM. Deferoxamine prevents cardiac hypertrophy and failure in the gerbil model of iron-induced cardiomyopathy. ACTA ACUST UNITED AC 2004; 142:332-40. [PMID: 14647037 DOI: 10.1016/s0022-2143(03)00135-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
To evaluate the effects of the iron chelator deferoxamine on the functional and structural manifestations of iron-induced cardiac dysfunction, we measured cardiac power, left ventricular systolic, and diastolic function as (dP/dt)max and (dP/dt)min, respectively, and left ventricular and septal wall thickness in isolated heart preparations derived from the Mongolian gerbil model of iron overload. We induced iron overload with weekly subcutaneous injections of iron dextran (800 mg/kg/wk); deferoxamine (DFO; 100 mg/kg) was administered twice daily by subcutaneous injection, 5 of 7 days each week; and control animals received weekly subcutaneous injections of dextran alone. Animals administered iron alone initially exhibited, at 5 weeks, increased cardiac power but by 12 to 20 weeks, cardiac power was severely diminished, with impairment of both systolic and diastolic function of the left ventricle and marked cardiac hypertrophy (P<.001 for all vs control animals). Administration of DFO with iron did not interfere with the initial augmentation of cardiac power at 5 weeks but prevented the subsequent deterioration in cardiac performance. After 12 to 20 weeks, gerbils given DFO with iron had mean values of cardiac power indistinguishable from those of control animals; both systolic and diastolic function were significantly enhanced not only in comparison with those of animals treated with iron alone but also with respect to controls. In addition, DFO prevented cardiac hypertrophy; mean ventricular and septal wall thickness in gerbils given DFO and iron were not significantly different from those in controls. In the gerbil model of iron overload, concurrent administration of DFO with iron prevents both the development of cardiac hypertrophy and the progressive deterioration in cardiac performance that are produced by chronic iron accumulation.
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Affiliation(s)
- Tianen Yang
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
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Brittenham GM, Kuryshev YA, Obejero-Paz CA, Yang T, Dong WQ, Levy MN, Brown AM. Yang et al response. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0022-2143(03)00039-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
Iron chelation may offer new approaches to the treatment and prevention of alcoholic liver disease. With chronic excess, either iron or alcohol alone may individually injure the liver and other organs. In combination, each exaggerates the adverse effects of the other. In alcoholic liver disease, both iron and alcohol contribute to the production of hepatic fibrosis through their effects on damaged hepatocytes, hepatic macrophages, hepatic stellate cells, and the extracellular matrix. The pivotal role of iron in these processes suggests that chelating iron may offer a new approach to arresting or ameliorating liver injury. For the past four decades, deferoxamine B mesylate has been the only iron-chelating agent generally available for clinical use. Clinical experience with deferoxamine has demonstrated the safety and effectiveness of iron chelation for the prevention and treatment of iron overload. Determined efforts to develop alternative agents have at last resulted in the development of a variety of candidate iron chelators that are now in or near clinical trial, including (a) the hexadentate phenolic aminocarboxylate HBED [N,N'-bis(2-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid], (b) the tridentate desferrithiocin derivative 4'-OH-dadmDFT [4'-hydroxy-(S)-desazadesmethyl-desferrithiocin; (S)-4,5-dihydro-2-(2,4-dihydroxyphenyl)-4-thiazolecarboxylic acid], (c) the tridentate triazole ICL670A [CGP72 670A; 4-[3,5-bis-(hydroxyphenyl)-1,2,4-triazol-1-yl]-benzoic acid], and (d) the bidentate hydroxypyridin-4-one deferiprone [L1, CP20; 1,2-dimethyl-3-hydroxypyridin-4-one]. These agents may provide new pharmacological means of averting or ameliorating liver damage in alcoholic liver disease by binding, inactivating, and eliminating the reactive forms of iron that contribute to oxidative injury of cellular components, are involved in signal transduction, or both.
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Affiliation(s)
- Gary M Brittenham
- Departments of Pediatrics and Medicine, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
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Templeton DM, Liu Y. Genetic regulation of cell function in response to iron overload or chelation. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1619:113-24. [PMID: 12527106 DOI: 10.1016/s0304-4165(02)00497-x] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Iron influences many aspects of cell function on different biochemical levels. This review considers effects mediated through iron-dependent changes in gene expression in mammalian cells. Several classes of related genes are responsive to cellular iron levels, but no clear patterns readily account for the toxicity of iron overload or the consequences of removal of iron with chelating agents. Here we group some of the genes influenced by iron status into those related to iron metabolism, oxygen and oxidative stress, energy metabolism, cell cycle regulation, and tissue fibrosis. Iron excess and chelation do not generally result in a continuous or graded transcriptional response, but indicate operation of distinct mechanisms. An emerging concept is that iron signals through generation of reactive oxygen species to activate transcription factors such as NF-kappaB, whereas iron removal mimics hypoxia, perhaps by disrupting iron-based O(2) sensors and influencing gene expression through, e.g., the hypoxia-inducible factor, HIF-1. Heme and other metalloporphyrins have other distinct mechanisms for regulating transcription. Regulation of gene expression through iron-responsive elements in mRNAs coded by several genes is one of the best understood mechanisms of translational control.
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Affiliation(s)
- Douglas M Templeton
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8.
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