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Helal NE, Ali LS, Elsaed WM, Berika M, Elhassan YH, El-Bayoumi KS, Badawy AA, El-Agawy MSED, Dawood AF, Eldesoqui M. Neuroprotective effects of selenium against lithium-induced cerebellar toxicity in rats: The role of apoptosis, gliosis, and aging markers. Tissue Cell 2025; 94:102779. [PMID: 39955833 DOI: 10.1016/j.tice.2025.102779] [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: 12/29/2024] [Revised: 01/28/2025] [Accepted: 02/01/2025] [Indexed: 02/18/2025]
Abstract
BACKGROUND Prolonged lithium therapy in psychiatric disorders may be complicated by multi-organ dysfunction, particularly in the nervous system. Toxicity to the cerebellum is one of these, which, while uncommon, inevitably emerges negatively and permanently. Selenium is a trace element regarded as one of the critical antioxidants. Numerous investigations have validated selenium's neuroprotective properties against various neurotoxic medications. The degree of affliction of the nerve cells is assessed using GFAP, a marker of astrocytosis; Caspase-3, a marker of apoptosis; and klotho, a marker of anti-aging. AIM OF THE STUDY This study is designed to investigate the cerebellar structural and functional changes in lithium-treated rats and the postulated neuroprotective role of selenium. METHODOLOGY A total of 24 adult male albino rats were divided into 4 groups: control, selenium (1 mg/kg in water solution by gavage daily), lithium (by intraperitoneal injection of 25 mg/kg lithium carbonate dissolved in 0.9 % NaCL twice daily for 4 weeks), and lithium-selenium group. Motor coordination was evaluated using the rotarod test. Cerebellar malonaldehyde (MDA) and reduced glutathione (GSH) were measured, and histopathological examination and immunohistochemical expression of Klotho, GFAP, and Caspase 3 were evaluated. RESULTS The lithium-treated group exhibited reduced latency on the rotarod test, elevated oxidative stress indicators, and an altered cerebellar structure in HE and cresyl violet-stained sections. Moreover, there was a diminished Klotho expression and increased levels of both caspase-3 and GFAP expression. Selenium administration reduced latency time, diminished oxidative stress markers, mitigated lithium-induced cerebellar alterations, increased Klotho expression, and lowered the expression of caspase-3 and GFAP. CONCLUSION Lithium exposure causes alterations in the cerebellar cortical structure in albino rats. Selenium protected the cerebellar cortex from such changes by enhancing Klotho expression, diminishing oxidative stress, and reducing apoptosis.
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Affiliation(s)
- Nora Elshehawy Helal
- Department of Human Anatomy and Embryology, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt; Department of Anatomy, Faculty of Medicine, Mansoura National University, Gamasa, Egypt.
| | - Lashin Saad Ali
- Department of Basic Medical Science-Faculty of Dentistry, Al-Ahliyya Amman University, Amman, Jordan; Physiology Department-Mansoura Faculty of Medicine-Mansoura University, Mansoura, Egypt
| | - Wael M Elsaed
- Department of Human Anatomy and Embryology, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt; Basic Sciences Department, Riyadh Elm University, Riyadh, Saudi Arabia.
| | - Mohamed Berika
- Department of Human Anatomy and Embryology, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt; Department of Rehabilitation Science, College of Applied Medical Sciences, King Saud University, Saudi Arabia.
| | - Yasir Hassan Elhassan
- Department of Basic Medical Science, College of Medicine, Taibah University, Madinah, Saudi Arabia
| | - Khaled S El-Bayoumi
- Department of Human Anatomy and Embryology, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt; Department of Basic Medical Sciences, Ibn Sina University for Medical Sciences, Amman 16197, Jordan
| | - Abdelnaser A Badawy
- Department of Biochemistry, Faculty of Medicine, Northern Border University, Arar, Saudi Arabia.
| | - Mosaab Salah El-Din El-Agawy
- Department of Human Anatomy and Embryology, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt; Ibn Sina National College for Medical Studies, Jeddah, Saudi Arabia.
| | - Amal Fahmy Dawood
- Department of Basic Medical Sciences, College of Medicine, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia.
| | - Mamdouh Eldesoqui
- Department of Basic Medical Sciences, College of Medicine, AlMaarefa University, P.O.Box 71666, Riyadh 11597, Saudi Arabia; Department of Anatomy and Embryology, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt.
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2
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Li N, Zhang Z, Shen L, Song G, Tian J, Liu Q, Ni J. Selenium metabolism and selenoproteins function in brain and encephalopathy. SCIENCE CHINA. LIFE SCIENCES 2025; 68:628-656. [PMID: 39546178 DOI: 10.1007/s11427-023-2621-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 06/09/2024] [Indexed: 11/17/2024]
Abstract
Selenium (Se) is an essential trace element of the utmost importance to human health. Its deficiency induces various disorders. Se species can be absorbed by organisms and metabolized to hydrogen selenide for the biosynthesis of selenoproteins, selenonucleic acids, or selenosugars. Se in mammals mainly acts as selenoproteins to exert their biological functions. The brain ranks highest in the specific hierarchy of organs to maintain the level of Se and the expression of selenoproteins under the circumstances of Se deficiency. Dyshomeostasis of Se and dysregulation of selenoproteins result in encephalopathy such as Alzheimer's disease, Parkinson's disease, depression, amyotrophic lateral sclerosis, and multiple sclerosis. This review provides a summary and discussion of Se metabolism, selenoprotein function, and their roles in modulating brain diseases based on the most currently published literature. It focuses on how Se is utilized and transported to the brain, how selenoproteins are biosynthesized and function physiologically in the brain, and how selenoproteins are involved in neurodegenerative diseases. At the end of this review, the perspectives and problems are outlined regarding Se and selenoproteins in the regulation of encephalopathy.
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Affiliation(s)
- Nan Li
- Shenzhen Key Laboratory of Marine Biotechnology and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518055, China
- Shenzhen-Hong Kong Institute of Brain Science, Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China
| | - Zhonghao Zhang
- Shenzhen Key Laboratory of Marine Biotechnology and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518055, China
| | - Liming Shen
- Shenzhen Key Laboratory of Marine Biotechnology and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518055, China
- Shenzhen-Hong Kong Institute of Brain Science, Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China
| | - Guoli Song
- Shenzhen Key Laboratory of Marine Biotechnology and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518055, China
| | - Jing Tian
- Shenzhen Key Laboratory of Marine Biotechnology and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518055, China.
| | - Qiong Liu
- Shenzhen Key Laboratory of Marine Biotechnology and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518055, China.
| | - Jiazuan Ni
- Shenzhen Key Laboratory of Marine Biotechnology and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518055, China
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Tomas-Sanchez C, Blanco-Alvarez VM, Gonzalez-Barrios JA, Martinez-Fong D, Soto-Rodriguez G, Brambila E, Gonzalez-Vazquez A, Aguilar-Peralta AK, Limón DI, Vargas-Castro V, Cebada J, Alatriste-Bueno V, Leon-Chavez BA. Prophylactic zinc and therapeutic selenium administration in adult rats prevents long-term cognitive and behavioral sequelae by a transient ischemic attack. Heliyon 2024; 10:e30017. [PMID: 38707461 PMCID: PMC11068621 DOI: 10.1016/j.heliyon.2024.e30017] [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: 10/30/2023] [Revised: 04/07/2024] [Accepted: 04/18/2024] [Indexed: 05/07/2024] Open
Abstract
The transient hypoxic-ischemic attack, also known as a minor stroke, can result in long-term neurological issues such as memory loss, depression, and anxiety due to an increase in nitrosative stress. The individual or combined administration of chronic prophylactic zinc and therapeutic selenium is known to reduce nitrosative stress in the first seven days post-reperfusion and, due to an antioxidant effect, prevent cell death. Besides, zinc or selenium, individually administered, also causes antidepressant and anxiolytic effects. Therefore, this work evaluated whether combining zinc and selenium could prevent stroke-elicited cognition and behavior deficits after 30 days post-reperfusion. Accordingly, we assessed the expression of growth factors at 7 days post-reperfusion, a four-time course of memory (from 7 to 28 days post-learning test), and cell proliferation, depression, and anxiety-like behavior at 30 days post-reperfusion. Male Wistar rats with a weight between 190 and 240 g) were treated with chronic prophylactic zinc administration with a concentration of 0.2 mg/kg for 15 days before common carotid artery occlusion (10 min) and then with therapeutic selenium (6 μg/kg) for 7 days post-reperfusion. Compared with individual administrations, the administration combined of prophylactic zinc and therapeutic selenium decreased astrogliosis, increased growth factor expression, and improved cell proliferation and survival in two regions, the hippocampus, and cerebral cortex. These effects prevented memory loss, depression, and anxiety-like behaviors. In conclusion, these results demonstrate that the prophylactic zinc administration combined with therapeutic selenium can reduce the long-term sequelae caused by the transient ischemic attack. Significance statement. A minor stroke caused by a transient ischemic attack can result in psychomotor sequelae that affect not only the living conditions of patients and their families but also the economy. The incidence of these micro-events among young people has increased in the world. Nonetheless, there is no deep understanding of how this population group responds to regular treatments (Ekker and et al., 2018) [1]. On the basis that zinc and selenium have antioxidant, anti-inflammatory, and regenerative properties in stroke animal models, our work explored whether the chronic combined administration of prophylactic zinc and therapeutic selenium could prevent neurological sequelae in the long term in a stroke rat model of unilateral common carotid artery occlusion (CCAO) by 10-min. Our results showed that this combined treatment provided a long-term neuroprotective effect by decreasing astrogliosis, memory loss, anxiety, and depression-like behavior.
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Affiliation(s)
- Constantino Tomas-Sanchez
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 sur y Av. San Claudio, 72570, Puebla, Mexico
| | - Victor Manuel Blanco-Alvarez
- Facultad de Enfermería, Benemérita Universidad Autónoma de Puebla, Av 25 Pte 1304, Colonia Volcanes, Puebla, Mexico
| | - Juan Antonio Gonzalez-Barrios
- Laboratorio de Medicina Genómica, Hospital regional 1° de Octubre, ISSSTE, Avenida Instituto Politécnico Nacional #1669, 07760, México D. F., Mexico
| | - Daniel Martinez-Fong
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, 07000, México D.F., Mexico
- Nanoparticle Therapy Institute, 404 Avenida Monte Blanco, Aguascalientes, 20120, Mexico
| | - Guadalupe Soto-Rodriguez
- Facultad de Medicina, Benemérita Universidad Autónoma de Puebla, 13 Sur 2702, Col. Volcanes, 72410, Puebla, Mexico
| | - Eduardo Brambila
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 sur y Av. San Claudio, 72570, Puebla, Mexico
| | - Alejandro Gonzalez-Vazquez
- Facultad de Medicina, Benemérita Universidad Autónoma de Puebla, 13 Sur 2702, Col. Volcanes, 72410, Puebla, Mexico
| | - Ana Karina Aguilar-Peralta
- Facultad de Medicina, Benemérita Universidad Autónoma de Puebla, 13 Sur 2702, Col. Volcanes, 72410, Puebla, Mexico
| | - Daniel I. Limón
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 sur y Av. San Claudio, 72570, Puebla, Mexico
| | - Viridiana Vargas-Castro
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 sur y Av. San Claudio, 72570, Puebla, Mexico
| | - Jorge Cebada
- Facultad de Medicina, Benemérita Universidad Autónoma de Puebla, 13 Sur 2702, Col. Volcanes, 72410, Puebla, Mexico
| | - Victorino Alatriste-Bueno
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 sur y Av. San Claudio, 72570, Puebla, Mexico
| | - Bertha Alicia Leon-Chavez
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 sur y Av. San Claudio, 72570, Puebla, Mexico
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Qiao L, Men L, Yu S, Yao J, Li Y, Wang M, Yu Y, Wang N, Ran L, Wu Y, Du J. Hepatic deficiency of selenoprotein S exacerbates hepatic steatosis and insulin resistance. Cell Death Dis 2022; 13:275. [PMID: 35347118 PMCID: PMC8960781 DOI: 10.1038/s41419-022-04716-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 02/18/2022] [Accepted: 03/09/2022] [Indexed: 12/13/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is closely associated with insulin resistance (IR) and type 2 diabetes mellitus (T2DM), which are all complex metabolic disorders. Selenoprotein S (SelS) is an endoplasmic reticulum (ER) resident selenoprotein involved in regulating ER stress and has been found to participate in the occurrence and development of IR and T2DM. However, the potential role and mechanism of SelS in NAFLD remains unclear. Here, we analyzed SelS expression in the liver of high-fat diet (HFD)-fed mice and obese T2DM model (db/db) mice and generated hepatocyte-specific SelS knockout (SelSH-KO) mice using the Cre-loxP system. We showed that hepatic SelS expression levels were significantly downregulated in HFD-fed mice and db/db mice. Hepatic SelS deficiency markedly increased ER stress markers in the liver and caused hepatic steatosis via increased fatty acid uptake and reduced fatty acid oxidation. Impaired insulin signaling was detected in the liver of SelSH-KO mice with decreased phosphorylation levels of insulin receptor substrate 1 (IRS1) and protein kinase B (PKB/Akt), which ultimately led to disturbed glucose homeostasis. Meanwhile, our results showed hepatic protein kinase Cɛ (PKCɛ) activation participated in the negative regulation of insulin signaling in SelSH-KO mice. Moreover, the inhibitory effect of SelS on hepatic steatosis and IR was confirmed by SelS overexpression in primary hepatocytes in vitro. Thus, we conclude that hepatic SelS plays a key role in regulating hepatic lipid accumulation and insulin action, suggesting that SelS may be a potential intervention target for the prevention and treatment of NAFLD and T2DM.
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Affiliation(s)
- Lu Qiao
- Department of Endocrinology, the First Affiliated Hospital of Dalian Medical University, Dalian, China.,Dalian Key Laboratory of Prevention and Treatment of Metabolic Diseases and the Vascular Complications, Dalian, China
| | - Lili Men
- Department of Endocrinology, the First Affiliated Hospital of Dalian Medical University, Dalian, China.,Dalian Key Laboratory of Prevention and Treatment of Metabolic Diseases and the Vascular Complications, Dalian, China
| | - Shanshan Yu
- Department of Endocrinology, the First Affiliated Hospital of Dalian Medical University, Dalian, China.,Dalian Key Laboratory of Prevention and Treatment of Metabolic Diseases and the Vascular Complications, Dalian, China
| | - Junjie Yao
- Department of Endocrinology, the First Affiliated Hospital of Dalian Medical University, Dalian, China.,Dalian Key Laboratory of Prevention and Treatment of Metabolic Diseases and the Vascular Complications, Dalian, China
| | - Yu Li
- Department of Endocrinology, the First Affiliated Hospital of Dalian Medical University, Dalian, China.,Dalian Key Laboratory of Prevention and Treatment of Metabolic Diseases and the Vascular Complications, Dalian, China
| | - Mingming Wang
- Department of Endocrinology, the First Affiliated Hospital of Dalian Medical University, Dalian, China.,Dalian Key Laboratory of Prevention and Treatment of Metabolic Diseases and the Vascular Complications, Dalian, China
| | - Ying Yu
- Department of Endocrinology, the First Affiliated Hospital of Dalian Medical University, Dalian, China.,Dalian Key Laboratory of Prevention and Treatment of Metabolic Diseases and the Vascular Complications, Dalian, China
| | - Ning Wang
- Institute for Genome Engineered Animal Models of Human Diseases, Dalian Medical University, Dalian, China.,National Center of Genetically Engineered Animal Models for International Research, Dalian Medical University, Dalian, China
| | - Liyuan Ran
- Institute for Genome Engineered Animal Models of Human Diseases, Dalian Medical University, Dalian, China.,National Center of Genetically Engineered Animal Models for International Research, Dalian Medical University, Dalian, China
| | - Yingjie Wu
- Institute for Genome Engineered Animal Models of Human Diseases, Dalian Medical University, Dalian, China. .,National Center of Genetically Engineered Animal Models for International Research, Dalian Medical University, Dalian, China. .,Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY, USA.
| | - Jianling Du
- Department of Endocrinology, the First Affiliated Hospital of Dalian Medical University, Dalian, China. .,Dalian Key Laboratory of Prevention and Treatment of Metabolic Diseases and the Vascular Complications, Dalian, China.
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5
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Ryan F, Khoshnam SE, Khodagholi F, Ashabi G, Ahmadiani A. How cytosolic compartments play safeguard functions against neuroinflammation and cell death in cerebral ischemia. Metab Brain Dis 2021; 36:1445-1467. [PMID: 34173922 DOI: 10.1007/s11011-021-00770-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 06/06/2021] [Indexed: 11/26/2022]
Abstract
Ischemic stroke is the second leading cause of mortality and disability globally. Neuronal damage following ischemic stroke is rapid and irreversible, and eventually results in neuronal death. In addition to activation of cell death signaling, neuroinflammation is also considered as another pathogenesis that can occur within hours after cerebral ischemia. Under physiological conditions, subcellular organelles play a substantial role in neuronal functionality and viability. However, their functions can be remarkably perturbed under neurological disorders, particularly cerebral ischemia. Therefore, their biochemical and structural response has a determining role in the sequel of neuronal cells and the progression of disease. However, their effects on cell death and neuroinflammation, as major underlying mechanisms of ischemic stroke, are still not understood. This review aims to provide a comprehensive overview of the contribution of each organelle on these pathological processes after ischemic stroke.
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Affiliation(s)
- Fari Ryan
- Centre for Research in Neuroscience, The Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Seyed Esmaeil Khoshnam
- Persian Gulf Physiology Research Centre, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Fariba Khodagholi
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ghorbangol Ashabi
- Department of Physiology, Faculty of Medicine, Tehran University of Medical Sciences, PO Box: 1417613151, Tehran, Iran.
| | - Abolhassan Ahmadiani
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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6
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Zhang J, Zhou H, Li H, Ying Z, Liu X. Research progress on separation of selenoproteins/Se-enriched peptides and their physiological activities. Food Funct 2021; 12:1390-1401. [PMID: 33464257 DOI: 10.1039/d0fo02236e] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Selenium (Se) is an essential nutrient associated with several physiological processes in humans and has raised interest because of its antioxidant and immune properties. Se deficiency is related to a variety of diseases and dysfunctions in humans. Due to its higher bioavailability and lower toxicity, organic Se is more recommendable than inorganic Se in the frame of a balanced diet. Se is present in 25 identified selenoproteins that commonly occur in human organisms. As part of selenocysteine (SeC), Se becomes co-translationally incorporated into the polypeptide chain and involved in the regulation of oxidative stress, redox mechanisms, and other crucial cellular processes responsible for innate and adaptive immune responses. This review presents the current information regarding the presence of selenoproteins in the human body, and the separation of selenoproteins and selenopeptides from various plants and their physiological roles in the immune and oxidation systems of humans. In general, the application of selenoproteins and Se-enriched peptides are practically important for the clinical arena, whereby it can be used for exploring new healthy foods.
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Affiliation(s)
- Jian Zhang
- National Soybean Processing Industry Technology Innovation Center, Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing 100048, Peoples' Republic of China.
| | - Haochun Zhou
- National Soybean Processing Industry Technology Innovation Center, Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing 100048, Peoples' Republic of China.
| | - He Li
- National Soybean Processing Industry Technology Innovation Center, Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing 100048, Peoples' Republic of China.
| | - Zhiwei Ying
- National Soybean Processing Industry Technology Innovation Center, Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing 100048, Peoples' Republic of China.
| | - Xinqi Liu
- National Soybean Processing Industry Technology Innovation Center, Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing 100048, Peoples' Republic of China.
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7
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Addinsall AB, Wright CR, Kotsiakos TL, Smith ZM, Cook TR, Andrikopoulos S, van der Poel C, Stupka N. Impaired exercise performance is independent of inflammation and cellular stress following genetic reduction or deletion of selenoprotein S. Am J Physiol Regul Integr Comp Physiol 2020; 318:R981-R996. [PMID: 32186893 DOI: 10.1152/ajpregu.00321.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Selenoprotein S (Seps1) can be protective against oxidative, endoplasmic reticulum (ER), and inflammatory stress. Seps1 global knockout mice are less active, possess compromised fast muscle ex vivo strength, and, depending on context, heightened inflammation. Oxidative, ER, and inflammatory stress modulates contractile function; hence, our aim was to investigate the effects of Seps1 gene dose on exercise performance. Seps1-/- knockout, Seps1-/+ heterozygous, and wild-type mice were randomized to 3 days of incremental, high-intensity treadmill running or a sedentary control group. On day 4, the in situ contractile function of fast tibialis anterior (TA) muscles was determined. Seps1 reduction or deletion compromised exercise capacity, decreasing distance run. TA strength was also reduced. In sedentary Seps1-/- knockout mice, TA fatigability was greater than wild-type mice, and this was ameliorated with exercise. Whereas, in Seps1+/- heterozygous mice, exercise compromised TA endurance. These impairments in exercise capacity and TA contractile function were not associated with increased inflammation or a dysregulated redox state. Seps1 is highly expressed in muscle fibers and blood vessels. Interestingly, Nos1 and Vegfa mRNA transcripts were decreased in TA muscles from Seps1-/- knockout and Seps1-/+ heterozygous mice. Impaired exercise performance with Seps1 reduction or deletion cannot be attributed to heightened cellular stress, but it may potentially be mediated, in part, by the effects of Seps1 on the microvasculature.
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Affiliation(s)
- Alex Bernard Addinsall
- Centre for Molecular and Medical Research, School of Medicine, Deakin University, Geelong, Victoria, Australia.,Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Craig Robert Wright
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| | - Taryan L Kotsiakos
- Centre for Molecular and Medical Research, School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Zoe M Smith
- School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | - Taylah R Cook
- School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | | | - Chris van der Poel
- Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Bundoora, Victoria, Australia
| | - Nicole Stupka
- Centre for Molecular and Medical Research, School of Medicine, Deakin University, Geelong, Victoria, Australia.,Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Bundoora, Victoria, Australia.,Department of Medicine-Western Health, The University of Melbourne, St. Albans, Victoria, Australia.,Australian Institute for Musculoskeletal Science, St. Albans, Victoria, Australia
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8
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Cockman EM, Narayan V, Willard B, Shetty SP, Copeland PR, Driscoll DM. Identification of the Selenoprotein S Positive UGA Recoding (SPUR) element and its position-dependent activity. RNA Biol 2019; 16:1682-1696. [PMID: 31432740 PMCID: PMC6844570 DOI: 10.1080/15476286.2019.1653681] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Selenoproteins are a unique class of proteins that contain the 21st amino acid, selenocysteine (Sec). Addition of Sec into a protein is achieved by recoding of the UGA stop codon. All 25 mammalian selenoprotein mRNAs possess a 3′ UTR stem-loop structure, the Selenocysteine Insertion Sequence (SECIS), which is required for Sec incorporation. It is widely believed that the SECIS is the major RNA element that controls Sec insertion, however recent findings in our lab suggest otherwise for Selenoprotein S (SelS). Here we report that the first 91 nucleotides of the SelS 3′ UTR contain a proximal stem loop (PSL) and a conserved sequence we have named the SelS Positive UGA Recoding (SPUR) element. We developed a SelS-V5/UGA surrogate assay for UGA recoding, which was validated by mass spectrometry to be an accurate measure of Sec incorporation in cells. Using this assay, we show that point mutations in the SPUR element greatly reduce recoding in the reporter; thus, the SPUR is required for readthrough of the UGA-Sec codon. In contrast, deletion of the PSL increased Sec incorporation. This effect was reversed when the PSL was replaced with other stem-loops or an unstructured sequence, suggesting that the PSL does not play an active role in Sec insertion. Additional studies revealed that the position of the SPUR relative to the UGA-Sec codon is important for optimal UGA recoding. Our identification of the SPUR element in the SelS 3′ UTR reveals a more complex regulation of Sec incorporation than previously realized.
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Affiliation(s)
- Eric M Cockman
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, USA.,Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Vivek Narayan
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Belinda Willard
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Sumangala P Shetty
- Department of Biochemistry and Molecular Biology, Rutgers University, New Brunswick, NJ, USA
| | - Paul R Copeland
- Department of Biochemistry and Molecular Biology, Rutgers University, New Brunswick, NJ, USA
| | - Donna M Driscoll
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, USA.,Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, OH, USA
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9
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Cell-Type Specific Analysis of Selenium-Related Genes in Brain. Antioxidants (Basel) 2019; 8:antiox8050120. [PMID: 31060314 PMCID: PMC6562762 DOI: 10.3390/antiox8050120] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 04/24/2019] [Accepted: 04/25/2019] [Indexed: 12/21/2022] Open
Abstract
Selenoproteins are a unique class of proteins that play key roles in redox signaling in the brain. This unique organ is comprised of a wide variety of cell types that includes excitatory neurons, inhibitory neurons, astrocytes, microglia, and oligodendrocytes. Whereas selenoproteins are known to be required for neural development and function, the cell-type specific expression of selenoproteins and selenium-related machinery has yet to be systematically investigated. Due to advances in sequencing technology and investment from the National Institutes of Health (NIH)-sponsored BRAIN initiative, RNA sequencing (RNAseq) data from thousands of cortical neurons can now be freely accessed and searched using the online RNAseq data navigator at the Allen Brain Atlas. Hence, we utilized this newly developed tool to perform a comprehensive analysis of the cell-type specific expression of selenium-related genes in brain. Select proteins of interest were further verified by means of multi-label immunofluorescent labeling of mouse brain sections. Of potential significance to neural selenium homeostasis, we report co-expression of selenoprotein P (SELENOP) and selenium binding protein 1 (SELENBP1) within astrocytes. These findings raise the intriguing possibility that SELENBP1 may negatively regulate astrocytic SELENOP synthesis and thereby limit downstream Se supply to neurons.
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Addinsall AB, Martin SD, Collier F, Conlan XA, Foletta VC, Stupka N. Differential regulation of cellular stress responses by the endoplasmic reticulum-resident Selenoprotein S (Seps1) in proliferating myoblasts versus myotubes. Physiol Rep 2018; 6:e13926. [PMID: 30557449 PMCID: PMC6296459 DOI: 10.14814/phy2.13926] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 10/22/2018] [Accepted: 10/23/2018] [Indexed: 01/03/2023] Open
Abstract
The antioxidant Selenoprotein S (Seps1, Selenos) is an endoplasmic reticulum (ER)-resident protein associated with metabolic and inflammatory disease. While Seps1 is highly expressed in skeletal muscle, its mechanistic role as an antioxidant in skeletal muscle cells is not well characterized. In C2C12 myotubes treated with palmitate for 24 h, endogenous Seps1 protein expression was upregulated twofold. Two different siRNA constructs were used to investigate whether decreased levels of Seps1 exacerbated lipid-induced oxidative and ER stress in C2C12 myotubes and myoblasts, which differ with regards to cell cycle state and metabolic phenotype. In myoblasts, Seps1 protein knockdown of ~50% or ~75% exacerbated cellular stress responses in the presence of palmitate; as indicated by decreased cell viability and proliferation, higher H2 O2 levels, a lower reduced to oxidized glutathione (GSH:GSSG) ratio, and enhanced gene expression of ER and oxidative stress markers. Even in the absence of palmitate, Seps1 knockdown increased oxidative stress in myoblasts. Whereas, in myotubes in the presence of palmitate, a ~50% knockdown of Seps1 was associated with a trend toward a marginal (3-5%) decrease in viability (P = 0.05), decreased cellular ROS levels, and a reduced mRNA transcript abundance of the cellular stress marker thioredoxin inhibitory binding protein (Txnip). Furthermore, no enhancement of gene markers of ER stress was observed in palmitate-treated myotubes in response to Seps1 knockdown. In conclusion, reduced Seps1 levels exacerbate nutrient-induced cellular stress responses to a greater extent in glycolytic, proliferating myoblasts than in oxidative, differentiated myotubes, thus demonstrating the importance of cell phenotype to Seps1 function.
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Affiliation(s)
- Alex B. Addinsall
- Centre for Molecular and Medical ResearchSchool of MedicineDeakin UniversityGeelongAustralia
| | - Sheree D. Martin
- Centre for Molecular and Medical ResearchSchool of MedicineDeakin UniversityGeelongAustralia
| | - Fiona Collier
- GCEID, University HospitalBarwon HealthGeelongAustralia
- School of MedicineDeakin UniversityGeelongAustralia
| | - Xavier A. Conlan
- Centre for Chemistry and BiotechnologySchool of Life and Environmental SciencesFaculty of Science, Engineering and Built EnvironmentDeakin UniversityGeelongAustralia
| | - Victoria C. Foletta
- Institute for Physical Activity and Nutrition (IPAN)School of Exercise and Nutrition SciencesDeakin UniversityGeelongAustralia
| | - Nicole Stupka
- Centre for Molecular and Medical ResearchSchool of MedicineDeakin UniversityGeelongAustralia
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Selenoprotein S silencing triggers mouse hepatoma cells apoptosis and necrosis involving in intracellular calcium imbalance and ROS-mPTP-ATP. Biochim Biophys Acta Gen Subj 2018; 1862:2113-2123. [PMID: 30017912 DOI: 10.1016/j.bbagen.2018.07.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 06/22/2018] [Accepted: 07/04/2018] [Indexed: 12/26/2022]
Abstract
Selenoprotein S (SelenoS) is one of the cellular endoplasmic reticulum (ER) and membrane located selenoproteins, and it has the main functions of anti-oxidation, anti-apoptosis and anti-ER stress. To investigate the effect of SelenoS silencing on mouse hepatoma cell death and the intracellular biological function of SelenoS, we knocked down SelenoS in Hepa1-6 cells, and detected ER stress, intracellular calcium homeostasis, mitochondrial dynamics, apoptosis and necrosis. To further explore whether reactive oxygen species (ROS) has an effect on apoptosis and necrosis under SelenoS silencing, we used NAC (2.5 mM) to pretreat cells, and detected ΔΨm, ATP, and apoptosis and necrosis rates. SelenoS silencing broke the intracellular calcium homeostasis, induced mitochondrial dynamic disorder, ROS accumulation, loss of ΔΨm and ATP, and triggered apoptosis and necrosis in mouse hepatoma cells. The clearance of ROS alleviated the loss of ΔΨm and ATP caused by silencing of SelenoS, reduced cell necrosis and increased apoptosis. However, SelenoS silencing did not cause ER stress in Hepa1-6 cells. These results indicate that SelenoS silencing triggers mouse hepatoma cells apoptosis and necrosis through affecting intracellular calcium homeostasis and ROS-mPTP-ATP participates in cell death transformation from apoptosis to necrosis to rise damage.
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Addinsall AB, Wright CR, Shaw CS, McRae NL, Forgan LG, Weng CH, Conlan XA, Francis PS, Smith ZM, Andrikopoulos S, Stupka N. Deficiency of selenoprotein S, an endoplasmic reticulum resident oxidoreductase, impairs the contractile function of fast-twitch hindlimb muscles. Am J Physiol Regul Integr Comp Physiol 2018; 315:R380-R396. [PMID: 29668323 DOI: 10.1152/ajpregu.00244.2017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Selenoprotein S (Seps1) is an endoplasmic reticulum (ER) resident antioxidant implicated in ER stress and inflammation. In human vastus lateralis and mouse hindlimb muscles, Seps1 localization and expression were fiber-type specific. In male Seps1+/- heterozygous mice, spontaneous physical activity was reduced compared with wild-type littermates ( d = 1.10, P = 0.029). A similar trend was also observed in Seps1-/- knockout mice ( d = 1.12, P = 0.051). Whole body metabolism, body composition, extensor digitorum longus (EDL), and soleus mass and myofiber diameter were unaffected by genotype. However, in isolated fast EDL muscles from Seps1-/- knockout mice, the force frequency curve (FFC; 1-120 Hz) was shifted downward versus EDL muscles from wild-type littermates ( d = 0.55, P = 0.002), suggestive of reduced strength. During 4 min of intermittent, submaximal (60 Hz) stimulation, the genetic deletion or reduction of Seps1 decreased EDL force production ( d = 0.52, P < 0.001). Furthermore, at the start of the intermittent stimulation protocol, when compared with the 60-Hz stimulation of the FFC, EDL muscles from Seps1-/- knockout or Seps1+/- heterozygous mice produced 10% less force than those from wild-type littermates ( d = 0.31, P < 0.001 and d = 0.39, P = 0.015). This functional impairment was associated with reduced mRNA transcript abundance of thioredoxin-1 ( Trx1), thioredoxin interacting protein ( Txnip), and the ER stress markers Chop and Grp94, whereas, in slow soleus muscles, Seps1 deletion did not compromise contractile function and Trx1 ( d = 1.38, P = 0.012) and Txnip ( d = 1.27, P = 0.025) gene expression was increased. Seps1 is a novel regulator of contractile function and cellular stress responses in fast-twitch muscles.
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Affiliation(s)
- Alex B Addinsall
- Centre for Molecular and Medical Research, School of Medicine, Deakin University, Waurn Ponds, Victoria , Australia
| | - Craig R Wright
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Waurn Ponds, Victoria , Australia
| | - Chris S Shaw
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Waurn Ponds, Victoria , Australia
| | - Natasha L McRae
- Centre for Molecular and Medical Research, School of Medicine, Deakin University, Waurn Ponds, Victoria , Australia
| | - Leonard G Forgan
- Centre for Molecular and Medical Research, School of Medicine, Deakin University, Waurn Ponds, Victoria , Australia
| | - Chia-Heng Weng
- Department of Medicine-Austin Health, The University of Melbourne , Heidelberg, Victoria , Australia
| | - Xavier A Conlan
- Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Faculty of Science, Engineering and Built Environment, Deakin University, Waurn Ponds, Victoria , Australia
| | - Paul S Francis
- Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Faculty of Science, Engineering and Built Environment, Deakin University, Waurn Ponds, Victoria , Australia
| | - Zoe M Smith
- Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Faculty of Science, Engineering and Built Environment, Deakin University, Waurn Ponds, Victoria , Australia
| | - Sofianos Andrikopoulos
- Department of Medicine-Austin Health, The University of Melbourne , Heidelberg, Victoria , Australia
| | - Nicole Stupka
- Centre for Molecular and Medical Research, School of Medicine, Deakin University, Waurn Ponds, Victoria , Australia
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Emerging roles of endoplasmic reticulum-resident selenoproteins in the regulation of cellular stress responses and the implications for metabolic disease. Biochem J 2018; 475:1037-1057. [PMID: 29559580 DOI: 10.1042/bcj20170920] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 02/12/2018] [Accepted: 02/13/2018] [Indexed: 12/25/2022]
Abstract
Chronic metabolic stress leads to cellular dysfunction, characterized by excessive reactive oxygen species, endoplasmic reticulum (ER) stress and inflammation, which has been implicated in the pathogenesis of obesity, type 2 diabetes and cardiovascular disease. The ER is gaining recognition as a key organelle in integrating cellular stress responses. ER homeostasis is tightly regulated by a complex antioxidant system, which includes the seven ER-resident selenoproteins - 15 kDa selenoprotein, type 2 iodothyronine deiodinase and selenoproteins S, N, K, M and T. Here, the findings from biochemical, cell-based and mouse studies investigating the function of ER-resident selenoproteins are reviewed. Human experimental and genetic studies are drawn upon to highlight the relevance of these selenoproteins to the pathogenesis of metabolic disease. ER-resident selenoproteins have discrete roles in the regulation of oxidative, ER and inflammatory stress responses, as well as intracellular calcium homeostasis. To date, only two of these ER-resident selenoproteins, selenoproteins S and N have been implicated in human disease. Nonetheless, the potential of all seven ER-resident selenoproteins to ameliorate metabolic dysfunction warrants further investigation.
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Rueli RHLH, Torres DJ, Dewing AST, Kiyohara AC, Barayuga SM, Bellinger MT, Uyehara-Lock JH, White LR, Moreira PI, Berry MJ, Perry G, Bellinger FP. Selenoprotein S Reduces Endoplasmic Reticulum Stress-Induced Phosphorylation of Tau: Potential Role in Selenate Mitigation of Tau Pathology. J Alzheimers Dis 2018; 55:749-762. [PMID: 27802219 DOI: 10.3233/jad-151208] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Previous studies demonstrated that selenium in the form of sodium selenate reduces neurofibrillary tangle formation in Alzheimer's disease models. Hyperphosphorylation of tau, which leads to formation of neurofibrillary tangles in Alzheimer's disease, is increased by endoplasmic reticulum (ER) stress. Selenoprotein S (SelS) is part of an ER membrane complex that removes misfolded proteins from the ER as a means to reduce ER stress. Selenate, as with other forms of selenium, will increase selenoprotein expression. We therefore proposed that increased SelS expression by selenate would contribute to the beneficial actions of selenate in Alzheimer's disease. SelS expression increased with ER stress and decreased under conditions of elevated glucose concentrations in the SH-SY5Y neuronal cell line. Reducing expression of SelS with siRNA promoted cell death in response to ER stress. Selenate increased SelS expression, which significantly correlated with decreased tau phosphorylation. Restricting SelS expression during ER stress conditions increased tau phosphorylation, and also promoted aggregation of phosphorylated tau in neurites and soma. In human postmortem brain, SelS expression coincided with neurofibrillary tangles, but not with amyloid-β plaques. These results indicate that selenate can alter phosphorylation of tau by increasing expression of SelS in Alzheimer's disease and potentially other neurodegenerative disorders.
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Affiliation(s)
- Rachel H L H Rueli
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, HI, USA
| | - Daniel J Torres
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, HI, USA
| | - Andrea S T Dewing
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, HI, USA
| | - Arlene C Kiyohara
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, HI, USA
| | - Stephanie M Barayuga
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, HI, USA
| | - Miyoko T Bellinger
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, HI, USA
| | - Jane H Uyehara-Lock
- Department of Pathology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, HI, USA
| | - Lon R White
- Pacific Health Research and Education Institute, Honolulu, HI, USA
| | - Paula I Moreira
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra and Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Marla J Berry
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, HI, USA
| | - George Perry
- UTSA Neurosciences Institute and Department of Biology, University of Texas at San Antonio, San Antonio, TX, USA
| | - Frederick P Bellinger
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, HI, USA
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15
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Yu SS, Du JL. Selenoprotein S: a therapeutic target for diabetes and macroangiopathy? Cardiovasc Diabetol 2017; 16:101. [PMID: 28797256 PMCID: PMC5553675 DOI: 10.1186/s12933-017-0585-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 08/01/2017] [Indexed: 12/14/2022] Open
Abstract
Inflammatory response, oxidative stress, and endoplasmic reticulum (ER) stress are important pathophysiological bases of the occurrence and development of diabetes mellitus (DM) and macroangiopathy complications. Selenoprotein S (SELENOS) is involved in the regulation of these mechanisms; therefore, its association with DM and macroangiopathy has gradually received attention from scholars worldwide. SELENOS has different biological functions in different tissues and organs: it exerts antioxidant protection and has anti-ER stress effects in the pancreas and blood vessels, while it promotes the occurrence and development of insulin resistance in the liver, adipose tissue, and skeletal muscle. In addition, studies have confirmed that some SELENOS gene polymorphisms can influence the inflammatory response and are closely associated with the risk for developing DM and macroangiopathy. Therefore, comprehensive understanding of the association between SELENOS and inflammation, oxidative stress, and ER stress may better elucidate and supplement the pathogenic mechanisms of DM and macroangiopathy complications. Furthermore, in-depth investigation of the association of SELENOS function in different tissues and organs with DM and macroangiopathy may facilitate the development of new strategies for the prevention and treatment of DM and macrovascular complications. Here, we summarize the consensus and controversy regarding functions of SELENOS on currently available evidence.
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Affiliation(s)
- Shan-Shan Yu
- Department of Endocrinology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, Liaoning, China
| | - Jian-Ling Du
- Department of Endocrinology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, Liaoning, China.
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Hao S, Hu J, Song S, Huang D, Xu H, Qian G, Gan F, Huang K. Selenium Alleviates Aflatoxin B₁-Induced Immune Toxicity through Improving Glutathione Peroxidase 1 and Selenoprotein S Expression in Primary Porcine Splenocytes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:1385-1393. [PMID: 26806088 DOI: 10.1021/acs.jafc.5b05621] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Selenium (Se) is generally known as an essential micronutrient and antioxidant for humans and animals. Aflatoxin B1 (AFB1) is a frequent contaminant of food and feed, causing immune toxicity and hepatotoxicity. Little has been done about the mechanisms of how Se protects against AFB1-induced immune toxicity. The aim of this present study is to investigate the protective effects of Se against AFB1 and the underlying mechanisms. The primary splenocytes isolated from healthy pigs were stimulated by anti-pig-CD3 monoclonal antibodies and treated by various concentrations of different Se forms and AFB1. The results showed that Se supplementation alleviated the immune toxicity of AFB1 in a dose-dependent manner, as demonstrated by increasing T-cell proliferation and interleukin-2 production. Addition of buthionine sulfoximine abrogated the protective effects of SeMet against AFB1. SeMet enhanced mRNA and protein expression of glutathione peroxidase 1 (GPx1), selenoprotein S (SelS), and thioredoxin reductase 1 without and with AFB1 treatments. Furthermore, knockdown of GPx1 and SelS by GPx1-specific siRNA and SelS-specific siRNA diminished the protective effects of SeMet against AFB1-induced immune toxicity. It is concluded that SeMet diminishes AFB1-induced immune toxicity through increasing antioxidant ability and improving GPx1 and SelS expression in splenocytes. This study suggests that organic selenium may become a promising supplementation to protect humans and animals against the decline in immunity caused by AFB1.
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Affiliation(s)
- Shu Hao
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing 210095, Jiangsu Province, China
| | - Junfa Hu
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing 210095, Jiangsu Province, China
| | - Suquan Song
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing 210095, Jiangsu Province, China
| | - Da Huang
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing 210095, Jiangsu Province, China
| | - Haibing Xu
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing 210095, Jiangsu Province, China
| | - Gang Qian
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing 210095, Jiangsu Province, China
| | - Fang Gan
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing 210095, Jiangsu Province, China
| | - Kehe Huang
- Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls and College of Veterinary Medicine, Nanjing Agricultural University , Nanjing 210095, Jiangsu Province, China
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17
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Ye Y, Fu F, Li X, Yang J, Liu H. Selenoprotein S Is Highly Expressed in the Blood Vessels and Prevents Vascular Smooth Muscle Cells From Apoptosis. J Cell Biochem 2015; 117:106-17. [DOI: 10.1002/jcb.25254] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 06/05/2015] [Indexed: 12/20/2022]
Affiliation(s)
- Yali Ye
- School of Chemistry and Chemical Engineering; Huazhong University of Science and Technology; Wuhan 430074 People's Republic of China
| | - Fen Fu
- School of Chemistry and Chemical Engineering; Huazhong University of Science and Technology; Wuhan 430074 People's Republic of China
| | - Xiaoming Li
- School of Chemistry and Chemical Engineering; Huazhong University of Science and Technology; Wuhan 430074 People's Republic of China
| | - Jie Yang
- School of Chemistry and Chemical Engineering; Huazhong University of Science and Technology; Wuhan 430074 People's Republic of China
| | - Hongmei Liu
- School of Chemistry and Chemical Engineering; Huazhong University of Science and Technology; Wuhan 430074 People's Republic of China
- Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica; Wuhan 430074 People's Republic of China
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18
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Solovyev ND. Importance of selenium and selenoprotein for brain function: From antioxidant protection to neuronal signalling. J Inorg Biochem 2015; 153:1-12. [PMID: 26398431 DOI: 10.1016/j.jinorgbio.2015.09.003] [Citation(s) in RCA: 187] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Revised: 09/03/2015] [Accepted: 09/09/2015] [Indexed: 12/21/2022]
Abstract
Multiple biological functions of selenium manifest themselves mainly via 25 selenoproteins that have selenocysteine at their active centre. Selenium is vital for the brain and seems to participate in the pathology of disorders such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and epilepsy. Since selenium was shown to be involved in diverse functions of the central nervous system, such as motor performance, coordination, memory and cognition, a possible role of selenium and selenoproteins in brain signalling pathways may be assumed. The aim of the present review is to analyse possible relations between selenium and neurotransmission. Selenoproteins seem to be of special importance in the development and functioning of GABAergic (GABA, γ-aminobutyric acid) parvalbumin positive interneurons of the cerebral cortex and hippocampus. Dopamine pathway might be also selenium dependent as selenium shows neuroprotection in the nigrostriatal pathway and also exerts toxicity towards dopaminergic neurons under higher concentrations. Recent findings also point to acetylcholine neurotransmission involvement. The role of selenium and selenoproteins in neurotransmission might not only be limited to their antioxidant properties but also to inflammation, influencing protein phosphorylation and ion channels, alteration of calcium homeostasis and brain cholesterol metabolism. Moreover, a direct signalling function was proposed for selenoprotein P through interaction with post-synaptic apoliprotein E receptors 2 (ApoER2).
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Affiliation(s)
- Nikolay D Solovyev
- Institute of Chemistry, St. Petersburg State University, St. Petersburg 198504, Russian Federation.
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19
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Association of selenoprotein S gene polymorphism with ischemic stroke: how strong is the evidence? Blood Coagul Fibrinolysis 2015; 26:588-9. [PMID: 26126030 DOI: 10.1097/mbc.0000000000000263] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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20
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Pillai R, Uyehara-Lock JH, Bellinger FP. Selenium and selenoprotein function in brain disorders. IUBMB Life 2014; 66:229-39. [PMID: 24668686 DOI: 10.1002/iub.1262] [Citation(s) in RCA: 143] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 03/10/2014] [Indexed: 01/14/2023]
Abstract
Selenoproteins are important for normal brain function, and decreased function of selenoproteins can lead to impaired cognitive function and neurological disorders. This review examines the possible roles of selenoproteins in Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and epilepsy. Selenium deficiency is associated with cognitive decline, and selenoproteins may be helpful in preventing neurodegeneration in AD. PD is associated with impaired function of glutathione peroxidase selenoenzymes. In HD, selenium deters lipid peroxidation by increasing specific glutathione peroxidases. Selenium deficiency increases risk of seizures in epilepsy, whereas supplementation may help to alleviate seizures. Further studies on the mechanisms of selenoprotein function will increase our understanding of how selenium and selenoproteins can be used in treatment and prevention of brain disorders.
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Affiliation(s)
- Roshan Pillai
- Department of Cell and Molecular Biology, University of Hawaii, John A. Burns School of Medicine, Honolulu, HI, USA
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21
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He L, Wang B, Yao Y, Su M, Ma H, Jia N. Protective effects of the SEPS1 gene on lipopolysaccharide-induced sepsis. Mol Med Rep 2014; 9:1869-76. [PMID: 24573439 DOI: 10.3892/mmr.2014.1991] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 01/28/2014] [Indexed: 11/05/2022] Open
Abstract
Septic shock and sequential multiple organ failure are the main cause of mortality in patients with sepsis. The induction of inflammation during sepsis is a complex biological cascade, which requires successful therapeutic intervention. Selenoprotein S (SEPS1) is a novel endoplasmic reticulum-resident protein and is important in the production of inflammatory cytokines. The present study attempted to assess the effect of SEPS1 suppression by small interfering RNA (siRNA) on mice with lipopolysaccharide (LPS)-induced sepsis. In total, 30 mice were randomly assigned to three groups: i) H group (LPS-induced sepsis group; n=10): Mice with intraperitoneal injection of LPS (10 mg/kg); ii) K group (scrambled siRNA group; n=10): Mice transfected with scrambled control siRNA 12 h prior to injection with LPS and iii) L group (SEPS1 siRNA group; n=10): Mice transfected with SEPS1 siRNA 12 h prior to injection with LPS. The effects of siRNA were evaluated by SEPS1 gene and protein expression, biochemical parameters including serum alanine transaminase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), lactic dehydrogenase (LDH), creatine kinase (CK) and myocardial kinase (CK-MB), as well as the cytokines interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). The phosphorylation of p38 mitogen-activated protein kinases (p38 MAPK) was also detected by western blot analysis. In the SEPS1 siRNA group, SEPS1 gene and protein expression decreased significantly, while the levels of TNF-α and IL-6 increased compared with the control group. The biochemical parameters of ALT, AST, BUN, LDH, CK and CK-MB were markedly increased in the SEPS1 siRNA group. The phosphorylation of p38 MAPK was also significantly activated. The decrease in SEPS1 gene and protein expression and the production of TNF-α and IL-6 may correlate with the activation of the p38 MAPK pathway. Biochemical factors and pathological results demonstrated that the damage to vital organs was aggravated. In conclusion, these findings suggested that SEPS1 may protect mice against LPS-induced sepsis and organ damage. Therefore, SEPS1 may be a new target to resolve LPS-induced sepsis.
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Affiliation(s)
- Lei He
- Department of Hepatobiliary Surgery, PLA General Hospital, Beijing 100853, P.R. China
| | - Bin Wang
- Department of Critical Care Medicine, PLA General Hospital, Beijing 100853, P.R. China
| | - Yuan Yao
- Department of Medical Quality Control, PLA General Hospital, Beijing 100853, P.R. China
| | - Maosheng Su
- Department of Hepatobiliary Surgery, PLA General Hospital, Beijing 100853, P.R. China
| | - Huanxian Ma
- Department of Hepatobiliary Surgery, PLA General Hospital, Beijing 100853, P.R. China
| | - Ning Jia
- Department of Nosocomial Infection and Disease Control, PLA General Hospital, Beijing 100853, P.R. China
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22
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Bubenik JL, Miniard AC, Driscoll DM. Alternative transcripts and 3'UTR elements govern the incorporation of selenocysteine into selenoprotein S. PLoS One 2013; 8:e62102. [PMID: 23614019 PMCID: PMC3628699 DOI: 10.1371/journal.pone.0062102] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 03/16/2013] [Indexed: 01/01/2023] Open
Abstract
Selenoprotein S (SelS) is a 189 amino acid trans-membrane protein that plays an important yet undefined role in the unfolded protein response. It has been proposed that SelS may function as a reductase, with the penultimate selenocysteine (Sec188) residue participating in a selenosulfide bond with cysteine (Cys174). Cotranslational incorporation of Sec into SelS depends on the recoding of the UGA codon, which requires a Selenocysteine Insertion Sequence (SECIS) element in the 3′UTR of the transcript. Here we identify multiple mechanisms that regulate the expression of SelS. The human SelS gene encodes two transcripts (variants 1 and 2), which differ in their 3′UTR sequences due to an alternative splicing event that removes the SECIS element from the variant 1 transcript. Both transcripts are widely expressed in human cell lines, with the SECIS-containing variant 2 mRNA being more abundant. In vitro experiments demonstrate that the variant 1 3′UTR does not allow readthrough of the UGA/Sec codon. Thus, this transcript would produce a truncated protein that does not contain Sec and cannot make the selenosulfide bond. While the variant 2 3′UTR does support Sec insertion, its activity is weak. Bioinformatic analysis revealed two highly conserved stem-loop structures, one in the proximal part of the variant 2 3′UTR and the other immediately downstream of the SECIS element. The proximal stem-loop promotes Sec insertion in the native context but not when positioned far from the UGA/Sec codon in a heterologous mRNA. In contrast, the 140 nucleotides downstream of the SECIS element inhibit Sec insertion. We also show that endogenous SelS is enriched at perinuclear speckles, in addition to its known localization in the endoplasmic reticulum. Our results suggest the expression of endogenous SelS is more complex than previously appreciated, which has implications for past and future studies on the function of this protein.
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Affiliation(s)
- Jodi L. Bubenik
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
- * E-mail: (JLB); (DMD)
| | - Angela C. Miniard
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Donna M. Driscoll
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, Ohio, United States of America
- * E-mail: (JLB); (DMD)
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23
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Steinbrenner H, Sies H. Selenium homeostasis and antioxidant selenoproteins in brain: implications for disorders in the central nervous system. Arch Biochem Biophys 2013; 536:152-7. [PMID: 23500141 DOI: 10.1016/j.abb.2013.02.021] [Citation(s) in RCA: 153] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 02/25/2013] [Accepted: 02/27/2013] [Indexed: 10/27/2022]
Abstract
The essential trace element selenium, as selenocysteine, is incorporated into antioxidant selenoproteins such as glutathione peroxidases (GPx), thioredoxin reductases (TrxR) and selenoprotein P (Sepp1). Although comparatively low in selenium content, the brain exhibits high priority for selenium supply and retention under conditions of dietary selenium deficiency. Liver-derived Sepp1 is the major transport protein in plasma to supply the brain with selenium, serving as a "survival factor" for neurons in culture. Sepp1 expression has also been detected within the brain. Presumably, astrocytes secrete Sepp1, which is subsequently taken up by neurons via the apolipoprotein E receptor 2 (ApoER2). Knock-out of Sepp1 or ApoER2 as well as neuron-specific ablation of selenoprotein biosynthesis results in neurological dysfunction in mice. Astrocytes, generally less vulnerable to oxidative stress than neurons, are capable of up-regulating the expression of antioxidant selenoproteins upon brain injury. Occurrence of neurological disorders has been reported occasionally in patients with inadequate nutritional selenium supply or a mutation in the gene encoding selenocysteine synthase, one of the enzymes involved in selenoprotein biosynthesis. In three large trials carried out among elderly persons, a low selenium status was associated with faster decline in cognitive functions and poor performance in tests assessing coordination and motor speed. Future research is required to better understand the role of selenium and selenoproteins in brain diseases including hepatic encephalopathy.
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Affiliation(s)
- Holger Steinbrenner
- Institute for Biochemistry and Molecular Biology I, Heinrich-Heine-University, Düsseldorf, Germany
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24
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Liu LX, Zhou XY, Li CS, Liu LQ, Huang SY, Zhou SN. Selenoprotein S expression in the rat brain following focal cerebral ischemia. Neurol Sci 2013; 34:1671-8. [DOI: 10.1007/s10072-013-1319-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Accepted: 01/21/2013] [Indexed: 11/30/2022]
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25
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Abstract
Selenium is an essential micronutrient in mammals, but is also recognized as toxic in excess. It is a non-metal with properties that are intermediate between the chalcogen elements sulfur and tellurium. Selenium exerts its biological functions through selenoproteins. Selenoproteins contain selenium in the form of the 21st amino acid, selenocysteine (Sec), which is an analog of cysteine with the sulfur-containing side chain replaced by a Se-containing side chain. Sec is encoded by the codon UGA, which is one of three termination codons for mRNA translation in non-selenoprotein genes. Recognition of the UGA codon as a Sec insertion site instead of stop requires a Sec insertion sequence (SECIS) element in selenoprotein mRNAs and a unique selenocysteyl-tRNA, both of which are recognized by specialized protein factors. Unlike the 20 standard amino acids, Sec is biosynthesized from serine on its tRNA. Twenty-five selenoproteins are encoded in the human genome. Most of the selenoprotein genes were discovered by bioinformatics approaches, searching for SECIS elements downstream of in-frame UGA codons. Sec has been described as having stronger nucleophilic and electrophilic properties than cysteine, and Sec is present in the catalytic site of all selenoenzymes. Most selenoproteins, whose functions are known, are involved in redox systems and signaling pathways. However, several selenoproteins are not well characterized in terms of their function. The selenium field has grown dramatically in the last few decades, and research on selenium biology is providing extensive new information regarding its importance for human health.
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Affiliation(s)
- Suguru Kurokawa
- Department of Cell & Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, 96813, USA,
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26
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Tanguy S, Grauzam S, de Leiris J, Boucher F. Impact of dietary selenium intake on cardiac health: experimental approaches and human studies. Mol Nutr Food Res 2012; 56:1106-21. [PMID: 22760983 DOI: 10.1002/mnfr.201100766] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Selenium, a dietary trace mineral, essential for humans and animals, exerts its effects mainly through its incorporation into selenoproteins. Adequate selenium intake is needed to maximize the activity of selenoproteins, among which glutathione peroxidases have been shown to play a major role in cellular defense against oxidative stress initiated by excess reactive oxygen species. In humans, a low selenium status has been linked to increased risk of various diseases, including heart disease. The main objective of this review is to present current knowledge on the role of selenium in cardiac health. Experimental studies have shown that selenium may exert protective effects on cardiac tissue in animal models involving oxidative stress. Because of the narrow safety margin of this mineral, most interventional studies in humans have reported inconsistent findings. Major determinants of selenium status in humans are not well understood and several nondietary factors might be associated with reduced selenium status. In this review, we discuss recent studies regarding the role of selenoproteins in the cardiovascular system, the effect of dietary intake on selenium status, the impact of selenium status on cardiac health, and the cellular mechanisms that can be involved in the physiological and toxic effects of selenium.
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27
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Fradejas N, Del Carmen Serrano-PÉREZ M, Tranque P, Calvo S. Selenoprotein S expression in reactive astrocytes following brain injury. Glia 2011; 59:959-72. [DOI: 10.1002/glia.21168] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 02/21/2011] [Indexed: 02/05/2023]
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28
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Shchedrina VA, Zhang Y, Labunskyy VM, Hatfield DL, Gladyshev VN. Structure-function relations, physiological roles, and evolution of mammalian ER-resident selenoproteins. Antioxid Redox Signal 2010; 12:839-49. [PMID: 19747065 PMCID: PMC2864662 DOI: 10.1089/ars.2009.2865] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Selenium is an essential trace element in mammals. The major biological form of this micronutrient is the amino acid selenocysteine, which is present in the active sites of selenoenzymes. Seven of 25 mammalian selenoproteins have been identified as residents of the endoplasmic reticulum, including the 15-kDa selenoprotein, type 2 iodothyronine deiodinase and selenoproteins K, M, N, S, and T. Most of these proteins are poorly characterized. However, recent studies implicate some of them in quality control of protein folding in the ER, retrotranslocation of misfolded proteins from the ER to the cytosol, metabolism of the thyroid hormone, and regulation of calcium homeostasis. In addition, some of these proteins are involved in regulation of glucose metabolism and inflammation. This review discusses evolution and structure-function relations of the ER-resident selenoproteins and summarizes recent findings on these proteins, which reveal the emerging important role of selenium and selenoproteins in ER function.
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Affiliation(s)
- Valentina A Shchedrina
- Redox Biology Center and Department of Biochemistry, University of Nebraska, Lincoln, NE, USA
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29
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Abstract
Selenoproteins are proteins containing selenium in the form of the 21st amino acid, selenocysteine. Members of this protein family have many diverse functions, but their synthesis is dependent on a common set of cofactors and on dietary selenium. Although the functions of many selenoproteins are unknown, several disorders involving changes in selenoprotein structure, activity or expression have been reported. Selenium deficiency and mutations or polymorphisms in selenoprotein genes and synthesis cofactors are implicated in a variety of diseases, including muscle and cardiovascular disorders, immune dysfunction, cancer, neurological disorders and endocrine function. Members of this unusual family of proteins have roles in a variety of cell processes and diseases.
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Affiliation(s)
- Frederick P Bellinger
- Department of Cell and Molecular Biology, John A Burns School of Medicine, University of Hawai'i, Honolulu, HI 96813, USA.
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