1
|
Sanchez-Aceves LM, Pérez-Alvarez I, Onofre-Camarena DB, Gutiérrez-Noya VM, Rosales-Pérez KE, Orozco-Hernández JM, Hernández-Navarro MD, Flores HI, Gómez-Olivan LM. Prolonged exposure to the synthetic glucocorticoid dexamethasone induces brain damage via oxidative stress and apoptotic response in adult Daniorerio. CHEMOSPHERE 2024; 364:143012. [PMID: 39103101 DOI: 10.1016/j.chemosphere.2024.143012] [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: 06/05/2024] [Revised: 07/11/2024] [Accepted: 08/02/2024] [Indexed: 08/07/2024]
Abstract
Due to its extensive use as a painkiller, anti-inflammatory, and immune modulatory agent, as well as its effectiveness in treating severe COVID-19, dexamethasone, a synthetic glucocorticoid, has gained attention not only for its impact on public health but also for its environmental implications. Various studies have reported its presence in aquatic environments, including urban waters, surface samples, sediments, drinking water, and wastewater effluents. However, limited information is available regarding its toxic effects on nontarget aquatic organisms. Therefore, this study aimed to investigate the mechanism of toxicity underlying dexamethasone-induced brain damage in the bioindicator Danio rerio following long-term exposure. Adult zebrafish were treated with environmentally relevant concentrations of dexamethasone (20, 40, and 60 ng L-1) for 28 days. To elucidate the possible mechanisms involved in the toxicity of the pharmaceutical compound, we conducted a behavioral test battery (Novel Tank and Light and Dark tests), oxidative stress biomarkers, acetylcholinesterase enzyme activity quantification, histopathological analysis, and gene expression analysis using qRT-PCR (p53, bcl-2, bax, caspase-3, nrf1, and nrf2).The results revealed that the pharmaceutical compound could produce anxiety-like symptoms, increase the oxidative-induced stress response, decrease the activity of acetylcholinesterase enzyme, and cause histopathological alterations, including perineuronal vacuolization, granular and molecular layers deterioration, cell swallowing and intracellular spaces. The expression of genes involved in the apoptotic process (p53, bax, and casp-3) and antioxidant defense (nrf1 and nrf2) was upregulated in response to oxidative damage, while the expression of the anti-apoptotic gene bcl-2 was down-regulated indicating that the environmental presence of dexamethasone may pose a threat to wildlife and human health.
Collapse
Affiliation(s)
- Livier M Sanchez-Aceves
- Laboratorio de Toxicología Ambiental, Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan s/n, Col. Residencial Colón, 50120, Toluca, Estado de México, Mexico
| | - Itzayana Pérez-Alvarez
- Facultad de Medicina, Universidad Autónoma del Estado de México. Paseo Tollocan /Jesús Carranza s/n. Toluca, 50120, Toluca, Estado de México, Mexico
| | - Diana Belén Onofre-Camarena
- Laboratorio de Toxicología Ambiental, Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan s/n, Col. Residencial Colón, 50120, Toluca, Estado de México, Mexico
| | - Verónica Margarita Gutiérrez-Noya
- Laboratorio de Toxicología Ambiental, Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan s/n, Col. Residencial Colón, 50120, Toluca, Estado de México, Mexico
| | - Karina Elisa Rosales-Pérez
- Laboratorio de Toxicología Ambiental, Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan s/n, Col. Residencial Colón, 50120, Toluca, Estado de México, Mexico
| | - José Manuel Orozco-Hernández
- Laboratorio de Toxicología Ambiental, Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan s/n, Col. Residencial Colón, 50120, Toluca, Estado de México, Mexico
| | - María Dolores Hernández-Navarro
- Laboratorio de Toxicología Ambiental, Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan s/n, Col. Residencial Colón, 50120, Toluca, Estado de México, Mexico
| | - Hariz Islas Flores
- Laboratorio de Toxicología Ambiental, Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan s/n, Col. Residencial Colón, 50120, Toluca, Estado de México, Mexico
| | - Leobardo Manuel Gómez-Olivan
- Laboratorio de Toxicología Ambiental, Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan s/n, Col. Residencial Colón, 50120, Toluca, Estado de México, Mexico.
| |
Collapse
|
2
|
Polansky H, Goral B. How an increase in the copy number of HSV-1 during latency can cause Alzheimer's disease: the viral and cellular dynamics according to the microcompetition model. J Neurovirol 2021; 27:895-916. [PMID: 34635992 DOI: 10.1007/s13365-021-01012-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 04/28/2021] [Accepted: 08/16/2021] [Indexed: 12/11/2022]
Abstract
Numerous studies observed a link between the herpes smplex virus-1 (HSV-1) and Alzheimer's disease. However, the exact viral and cellular dynamics that lead from an HSV-1 infection to Alzheimer's disease are unknown. In this paper, we use the microcompetition model to formulate these dynamics by connecting seemingly unconnected observations reported in the literature. We concentrate on four pathologies characteristic of Alzheimer's disease. First, we explain how an increase in the copy number of HSV-1 during latency can decrease the expression of BECN1/Beclin1, the degradative trafficking protein, which, in turn, can cause a dysregulation of autophagy and Alzheimer's disease. Second, we show how an increase in the copy number of the latent HSV-1 can decrease the expression of many genes important for mitochondrial genome metabolism, respiratory chain, and homeostasis, which can lead to oxidative stress and neuronal damage, resulting in Alzheimer's disease. Third, we describe how an increase in this copy number can reduce the concentration of the NMDA receptor subunits NR1 and NR2b (Grin1 and Grin2b genes), and brain derived neurotrophic factor (BDNF), which can cause an impaired synaptic plasticity, Aβ accumulation and eventually Alzheimer's disease. Finally, we show how an increase in the copy number of HSV-1 in neural stem/progenitor cells in the hippocampus during the latent phase can lead to an abnormal quantity and quality of neurogenesis, and the clinical presentation of Alzheimer's disease. Since the current understanding of the dynamics and homeostasis of the HSV-1 reservoir during latency is limited, the proposed model represents only a first step towards a complete understanding of the relationship between the copy number of HSV-1 during latency and Alzheimer's disease.
Collapse
Affiliation(s)
- Hanan Polansky
- The Center for the Biology of Chronic Disease (CBCD), 3 Germay Dr, Wilmington, DE, 19804, USA.
| | - Benjamin Goral
- The Center for the Biology of Chronic Disease (CBCD), 3 Germay Dr, Wilmington, DE, 19804, USA
| |
Collapse
|
3
|
Cediel Ulloa A, Gliga A, Love TM, Pineda D, Mruzek DW, Watson GE, Davidson PW, Shamlaye CF, Strain JJ, Myers GJ, van Wijngaarden E, Ruegg J, Broberg K. Prenatal methylmercury exposure and DNA methylation in seven-year-old children in the Seychelles Child Development Study. ENVIRONMENT INTERNATIONAL 2021; 147:106321. [PMID: 33340986 DOI: 10.1016/j.envint.2020.106321] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 11/06/2020] [Accepted: 12/02/2020] [Indexed: 05/27/2023]
Abstract
BACKGROUND Methylmercury (MeHg) is present in fish and is a neurotoxicant at sufficiently high levels. One potential mechanism of MeHg toxicity early in life is epigenetic dysregulation that may affect long-term neurodevelopment. Altered DNA methylation of nervous system-related genes has been associated with adult mental health outcomes. OBJECTIVE To assess associations between prenatal MeHg exposure and DNA methylation (at the cytosine of CG dinucleotides, CpGs) in three nervous system-related genes, encoding brain-derived neurotropic factor (BDNF), glutamate receptor subunit NR2B (GRIN2B), and the glucocorticoid receptor (NR3C1), in children who were exposed to MeHg in utero. METHODS We tested 406 seven-year-old Seychellois children participating in the Seychelles Child Development Study (Nutrition Cohort 2), who were prenatally exposed to MeHg from maternal fish consumption. Total mercury in maternal hair (prenatal MeHg exposure measure) collected during pregnancy was measured using atomic absorption spectroscopy. Methylation in DNA from the children's saliva was measured by pyrosequencing. To assess associations between prenatal MeHg exposure and CpG methylation at seven years of age, we used multivariable linear regression models adjusted for covariates. RESULTS We identified associations with prenatal MeHg exposure for DNA methylation of one GRIN2B CpG and two NR3C1 CpGs out of 12 total CpG sites. Higher prenatal MeHg was associated with higher methylation for each CpG site. For example, NR3C1 CpG3 had an expected increase of 0.03-fold for each additional 1 ppm of prenatal MeHg (B = 0.030, 95% CI 0.001, 0.059; p = 0.047). Several CpG sites associated with MeHg are located in transcription factor binding sites and the observed methylation changes are predicted to lead to lower gene expression. CONCLUSIONS In a population of people who consume large amounts of fish, we showed that higher prenatal MeHg exposure was associated with differential DNA methylation at seven years of age at specific CpG sites that may influence neurodevelopment and mental health.
Collapse
Affiliation(s)
- Andrea Cediel Ulloa
- Institute of Environmental Medicine, Karolinska Institutet, Box 210, 171 77 Stockholm, Sweden; Department of Organism Biology, Uppsala University, Kåbovägen 4, 752 36 Uppsala, Sweden
| | - Anda Gliga
- Institute of Environmental Medicine, Karolinska Institutet, Box 210, 171 77 Stockholm, Sweden
| | - Tanzy M Love
- University of Rochester Medical Center, School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY 14642, USA
| | - Daniela Pineda
- Department of Laboratory Medicine, Division of Occupational and Environmental Medicine, Lund University, Scheelevägen 8, 22185 Lund, Sweden
| | - Daniel W Mruzek
- University of Rochester Medical Center, School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY 14642, USA
| | - Gene E Watson
- University of Rochester Medical Center, School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY 14642, USA
| | - Philip W Davidson
- University of Rochester Medical Center, School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY 14642, USA
| | | | - J J Strain
- Nutrition Innovation Centre for Food and Health (NICHE), Ulster University, Coleraine, Northern Ireland Bt52 1SA, UK
| | - Gary J Myers
- University of Rochester Medical Center, School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY 14642, USA
| | - Edwin van Wijngaarden
- University of Rochester Medical Center, School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY 14642, USA
| | - Joelle Ruegg
- Department of Organism Biology, Uppsala University, Kåbovägen 4, 752 36 Uppsala, Sweden
| | - Karin Broberg
- Institute of Environmental Medicine, Karolinska Institutet, Box 210, 171 77 Stockholm, Sweden; Department of Laboratory Medicine, Division of Occupational and Environmental Medicine, Lund University, Scheelevägen 8, 22185 Lund, Sweden.
| |
Collapse
|
4
|
Chicherin IV, Dashinimaev E, Baleva M, Krasheninnikov I, Levitskii S, Kamenski P. Cytochrome c Oxidase on the Crossroads of Transcriptional Regulation and Bioenergetics. Front Physiol 2019; 10:644. [PMID: 31231235 PMCID: PMC6558401 DOI: 10.3389/fphys.2019.00644] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 05/07/2019] [Indexed: 11/13/2022] Open
Abstract
Mitochondria are the organelles of eukaryotic cells responsible for the ATP production by means of the electron transfer chain (ETC). Its work is under strict genetic control providing the correct assembly of the enzyme complexes and the interface to adapt the energetic demands of the cell to the environment. These mechanisms are particularly developed in the cells with high energy consumption, like neurons and myocytes. This review summarizes several aspects of the involvement of the ETC complexes in the transcriptional control mechanisms of the neurons and other cells. Their influence on the differentiation of neurons is also discussed.
Collapse
Affiliation(s)
- Ivan Vladimirovich Chicherin
- Department of Molecular Biology, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia.,Institute of Functional Genomics, Lomonosov Moscow State University, Moscow, Russia
| | - Erdem Dashinimaev
- Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia.,Pirogov Russian National Research Medical University, Moscow, Russia
| | - Mariia Baleva
- Department of Molecular Biology, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Igor Krasheninnikov
- Department of Molecular Biology, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Sergey Levitskii
- Department of Molecular Biology, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Piotr Kamenski
- Department of Molecular Biology, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| |
Collapse
|
5
|
Niu N, Li Z, Zhu M, Sun H, Yang J, Xu S, Zhao W, Song R. Effects of nuclear respiratory factor‑1 on apoptosis and mitochondrial dysfunction induced by cobalt chloride in H9C2 cells. Mol Med Rep 2019; 19:2153-2163. [PMID: 30628711 PMCID: PMC6390059 DOI: 10.3892/mmr.2019.9839] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 09/28/2018] [Indexed: 01/31/2023] Open
Abstract
Hypoxia-induced apoptosis occurs in various diseases. Cobalt chloride (CoCl2) is a hypoxia mimic agent that is frequently used in studies investigating the mechanisms of hypoxia. Nuclear respiratory factor-1 (NRF-1) is a transcription factor with an important role in the expression of mitochondrial respiratory and mitochondria-associated genes. However, few studies have evaluated the effects of NRF-1 on apoptosis, particularly with regard to damage caused by CoCl2. In the present study, the role of NRF-1 in mediating CoCl2-induced apoptosis was investigated using cell viability analysis, flow cytometry, fluorescence imaging, western blotting analysis, energy metabolism analysis and reverse transcription-quantitative polymerase chain reaction. The present results revealed that the apoptosis caused by CoCl2 could be alleviated by NRF-1. Furthermore, overexpression of NRF-1 increased the expression of B-cell lymphoma-2, hypoxia inducible factor-1α and NRF-2. Also, cell damage induced by CoCl2 may be associated with depolarization of mitochondrial membrane potential, and NRF-1 suppressed this effect. Notably, the oxygen consumption rate (OCR) was reduced in CoCl2-treated cells, whereas overexpression of NRF-1 enhanced the OCR, suggesting that NRF-1 had protective effects. In summary, the present study demonstrated that NRF-1 protected against CoCl2-induced apoptosis, potentially by strengthening mitochondrial function to resist CoCl2-induced damage to H9C2 cells. The results of the present study provide a possible way for the investigation of myocardial diseases.
Collapse
Affiliation(s)
- Nan Niu
- College of Basic Medicine, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750001, P.R. China
| | - Zihua Li
- School of Pharmacy, Tsinghua University, Beijing 100084, P.R. China
| | - Mingxing Zhu
- College of Basic Medicine, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750001, P.R. China
| | - Hongli Sun
- College of Basic Medicine, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750001, P.R. China
| | - Jihui Yang
- College of Basic Medicine, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750001, P.R. China
| | - Shimei Xu
- College of Basic Medicine, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750001, P.R. China
| | - Wei Zhao
- College of Basic Medicine, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750001, P.R. China
| | - Rong Song
- Department of Critical Care Medicine, The Fifth Hospital of the Chinese People's Liberation Army, Yinchuan, Ningxia Hui Autonomous Region 750001, P.R. China
| |
Collapse
|
6
|
Alavian-Ghavanini A, Lin PI, Lind PM, Risén Rimfors S, Halin Lejonklou M, Dunder L, Tang M, Lindh C, Bornehag CG, Rüegg J. Prenatal Bisphenol A Exposure is Linked to Epigenetic Changes in Glutamate Receptor Subunit Gene Grin2b in Female Rats and Humans. Sci Rep 2018; 8:11315. [PMID: 30054528 PMCID: PMC6063959 DOI: 10.1038/s41598-018-29732-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 07/17/2018] [Indexed: 12/15/2022] Open
Abstract
Bisphenol A (BPA) exposure has been linked to neurodevelopmental disorders and to effects on epigenetic regulation, such as DNA methylation, at genes involved in brain function. High doses of BPA have been shown to change expression and regulation of one such gene, Grin2b, in mice. Yet, if such changes occur at relevant doses in animals and humans has not been addressed. We investigated if low-dose developmental BPA exposure affects DNA methylation and expression of Grin2b in brains of adult rats. Furthermore, we assessed associations between prenatal BPA exposure and Grin2b methylation in 7-year old children. We found that Grin2b mRNA expression was increased and DNA methylation decreased in female, but not in male rats. In humans, prenatal BPA exposure was associated with increased methylation levels in girls. Additionally, low APGAR scores, a predictor for increased risk for neurodevelopmental diseases, were associated with higher Grin2b methylation levels in girls. Thus, we could link developmental BPA exposure and low APGAR scores to changes in the epigenetic regulation of Grin2b, a gene important for neuronal function, in a sexual dimorphic fashion. Discrepancies in exact locations and directions of the DNA methylation change might reflect differences between species, analysed tissues, exposure level and/or timing.
Collapse
Affiliation(s)
- Ali Alavian-Ghavanini
- Swetox, Karolinska Institutet, Unit of Toxicology Sciences, Forskargatan 20, 151 36, Södertälje, Sweden
- Karolinska Institutet, Department of Clinical Neuroscience, Centre for Molecular Medicine (CMM), 171 64, Solna, Sweden
| | - Ping-I Lin
- Karlstad University, Department of Health Sciences, 651 88, Karlstad, Sweden
| | - P Monica Lind
- Uppsala University, Department of Medical Sciences, Occupational and Environmental Medicine, 751 85, Uppsala, Sweden
| | - Sabina Risén Rimfors
- Swetox, Karolinska Institutet, Unit of Toxicology Sciences, Forskargatan 20, 151 36, Södertälje, Sweden
| | - Margareta Halin Lejonklou
- Uppsala University, Department of Medical Sciences, Occupational and Environmental Medicine, 751 85, Uppsala, Sweden
| | - Linda Dunder
- Uppsala University, Department of Medical Sciences, Occupational and Environmental Medicine, 751 85, Uppsala, Sweden
| | - Mandy Tang
- Swetox, Karolinska Institutet, Unit of Toxicology Sciences, Forskargatan 20, 151 36, Södertälje, Sweden
| | - Christian Lindh
- Lund University, Division of Occupational and Environmental Medicine, Lund University, 221 85, Lund, Sweden
| | - Carl-Gustaf Bornehag
- Karlstad University, Department of Health Sciences, 651 88, Karlstad, Sweden
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Joëlle Rüegg
- Swetox, Karolinska Institutet, Unit of Toxicology Sciences, Forskargatan 20, 151 36, Södertälje, Sweden.
- Karolinska Institutet, Department of Clinical Neuroscience, Centre for Molecular Medicine (CMM), 171 64, Solna, Sweden.
| |
Collapse
|
7
|
Comparative biochemistry of cytochrome c oxidase in animals. Comp Biochem Physiol B Biochem Mol Biol 2017; 224:170-184. [PMID: 29180239 DOI: 10.1016/j.cbpb.2017.11.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 11/06/2017] [Accepted: 11/07/2017] [Indexed: 12/19/2022]
Abstract
Cytochrome c oxidase (COX), the terminal enzyme of the electron transport system, is central to aerobic metabolism of animals. Many aspects of its structure and function are highly conserved, yet, paradoxically, it is also an important model for studying the evolution of the metabolic phenotype. In this review, part of a special issue honouring Peter Hochachka, we consider the biology of COX from the perspective of comparative and evolutionary biochemistry. The approach is to consider what is known about the enzyme in the context of conventional biochemistry, but focus on how evolutionary researchers have used this background to explore the role of the enzyme in biochemical adaptation of animals. In synthesizing the conventional and evolutionary biochemistry, we hope to identify synergies and future research opportunities. COX represents a rare opportunity for researchers to design studies that span the breadth of biology: molecular genetics, protein biochemistry, enzymology, metabolic physiology, organismal performance, evolutionary biology, and phylogeography.
Collapse
|
8
|
Preciados M, Yoo C, Roy D. Estrogenic Endocrine Disrupting Chemicals Influencing NRF1 Regulated Gene Networks in the Development of Complex Human Brain Diseases. Int J Mol Sci 2016; 17:E2086. [PMID: 27983596 PMCID: PMC5187886 DOI: 10.3390/ijms17122086] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 11/21/2016] [Accepted: 11/29/2016] [Indexed: 12/13/2022] Open
Abstract
During the development of an individual from a single cell to prenatal stages to adolescence to adulthood and through the complete life span, humans are exposed to countless environmental and stochastic factors, including estrogenic endocrine disrupting chemicals. Brain cells and neural circuits are likely to be influenced by estrogenic endocrine disruptors (EEDs) because they strongly dependent on estrogens. In this review, we discuss both environmental, epidemiological, and experimental evidence on brain health with exposure to oral contraceptives, hormonal therapy, and EEDs such as bisphenol-A (BPA), polychlorinated biphenyls (PCBs), phthalates, and metalloestrogens, such as, arsenic, cadmium, and manganese. Also we discuss the brain health effects associated from exposure to EEDs including the promotion of neurodegeneration, protection against neurodegeneration, and involvement in various neurological deficits; changes in rearing behavior, locomotion, anxiety, learning difficulties, memory issues, and neuronal abnormalities. The effects of EEDs on the brain are varied during the entire life span and far-reaching with many different mechanisms. To understand endocrine disrupting chemicals mechanisms, we use bioinformatics, molecular, and epidemiologic approaches. Through those approaches, we learn how the effects of EEDs on the brain go beyond known mechanism to disrupt the circulatory and neural estrogen function and estrogen-mediated signaling. Effects on EEDs-modified estrogen and nuclear respiratory factor 1 (NRF1) signaling genes with exposure to natural estrogen, pharmacological estrogen-ethinyl estradiol, PCBs, phthalates, BPA, and metalloestrogens are presented here. Bioinformatics analysis of gene-EEDs interactions and brain disease associations identified hundreds of genes that were altered by exposure to estrogen, phthalate, PCBs, BPA or metalloestrogens. Many genes modified by EEDs are common targets of both 17 β-estradiol (E2) and NRF1. Some of these genes are involved with brain diseases, such as Alzheimer's Disease (AD), Parkinson's Disease, Huntington's Disease, Amyotrophic Lateral Sclerosis, Autism Spectrum Disorder, and Brain Neoplasms. For example, the search of enriched pathways showed that top ten E2 interacting genes in AD-APOE, APP, ATP5A1, CALM1, CASP3, GSK3B, IL1B, MAPT, PSEN2 and TNF-underlie the enrichment of the Kyoto Encyclopedia of Genes and Genomes (KEGG) AD pathway. With AD, the six E2-responsive genes are NRF1 target genes: APBB2, DPYSL2, EIF2S1, ENO1, MAPT, and PAXIP1. These genes are also responsive to the following EEDs: ethinyl estradiol (APBB2, DPYSL2, EIF2S1, ENO1, MAPT, and PAXIP1), BPA (APBB2, EIF2S1, ENO1, MAPT, and PAXIP1), dibutyl phthalate (DPYSL2, EIF2S1, and ENO1), diethylhexyl phthalate (DPYSL2 and MAPT). To validate findings from Comparative Toxicogenomics Database (CTD) curated data, we used Bayesian network (BN) analysis on microarray data of AD patients. We observed that both gender and NRF1 were associated with AD. The female NRF1 gene network is completely different from male human AD patients. AD-associated NRF1 target genes-APLP1, APP, GRIN1, GRIN2B, MAPT, PSEN2, PEN2, and IDE-are also regulated by E2. NRF1 regulates targets genes with diverse functions, including cell growth, apoptosis/autophagy, mitochondrial biogenesis, genomic instability, neurogenesis, neuroplasticity, synaptogenesis, and senescence. By activating or repressing the genes involved in cell proliferation, growth suppression, DNA damage/repair, apoptosis/autophagy, angiogenesis, estrogen signaling, neurogenesis, synaptogenesis, and senescence, and inducing a wide range of DNA damage, genomic instability and DNA methylation and transcriptional repression, NRF1 may act as a major regulator of EEDs-induced brain health deficits. In summary, estrogenic endocrine disrupting chemicals-modified genes in brain health deficits are part of both estrogen and NRF1 signaling pathways. Our findings suggest that in addition to estrogen signaling, EEDs influencing NRF1 regulated communities of genes across genomic and epigenomic multiple networks may contribute in the development of complex chronic human brain health disorders.
Collapse
Affiliation(s)
- Mark Preciados
- Department of Environmental & Occupational Health, Florida International University, Miami, FL 33199, USA.
| | - Changwon Yoo
- Department of Biostatistics, Florida International University, Miami, FL 33199, USA.
| | - Deodutta Roy
- Department of Environmental & Occupational Health, Florida International University, Miami, FL 33199, USA.
| |
Collapse
|
9
|
Nair B, Wong-Riley MTT. Transcriptional Regulation of Brain-derived Neurotrophic Factor Coding Exon IX: ROLE OF NUCLEAR RESPIRATORY FACTOR 2. J Biol Chem 2016; 291:22583-22593. [PMID: 27624937 DOI: 10.1074/jbc.m116.742304] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 09/09/2016] [Indexed: 01/22/2023] Open
Abstract
Brain-derived neurotrophic factor (BDNF) is an active neurotrophin abundantly expressed throughout the nervous system. It plays an important role in synaptic transmission, plasticity, neuronal proliferation, differentiation, survival, and death. The Bdnf gene in rodents has eight non-coding exons and only a single coding exon (IX). Despite its recognized regulation by neuronal activity, relatively little is known about its transcriptional regulation, and even less about the transcription factor candidates that may play such a role. The goal of the present study was to probe for such a candidate that may regulate exon IX in the rat Bdnf gene. Our in silico analysis revealed tandem binding sites for nuclear respiratory factor 2 (NRF-2) on the promoter of exon IX. NRF-2 is of special significance because it co-regulates the expressions of mediators of energy metabolism (cytochrome c oxidase) and mediators of neuronal activity (glutamatergic receptors). To test our hypothesis that NRF-2 also regulates the Bdnf gene, we performed electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), promoter cloning, and site-directed mutagenesis, real-time quantitative PCR (RT-qPCR), and Western blotting analysis. Results indicate that NRF-2 functionally regulates exon IX of the rat Bdnf gene. The binding sites of NRF-2 are conserved between rats and mice. Overexpressing NRF-2 up-regulated the expression of Bdnf exon IX, whereas knocking down NRF-2 down-regulated such expression. These findings are consistent with our hypothesis that NRF-2, in addition to regulating the coupling between neuronal activity and energy metabolism, also regulates the expression of BDNF, which is intimately associated with energy-demanding neuronal activity.
Collapse
Affiliation(s)
- Bindu Nair
- From the Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Margaret T T Wong-Riley
- From the Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| |
Collapse
|
10
|
Meparishvili M, Nozadze M, Margvelani G, McCabe BJ, Solomonia RO. A Proteomic Study of Memory After Imprinting in the Domestic Chick. Front Behav Neurosci 2015; 9:319. [PMID: 26635566 PMCID: PMC4660867 DOI: 10.3389/fnbeh.2015.00319] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 11/08/2015] [Indexed: 12/19/2022] Open
Abstract
The intermediate and medial mesopallium (IMM) of the domestic chick forebrain has previously been shown to be a memory system for visual imprinting. Learning-related changes occur in certain plasma membrane and mitochondrial proteins in the IMM. Two-dimensional gel electrophoresis/mass spectrometry has been employed to identify more comprehensively learning-related expression of proteins in the membrane-mitochondrial fraction of the IMM 24 h after training. We inquired whether amounts of these proteins in the IMM and a control region (posterior pole of the nidopallium, PPN) are correlated with a behavioral estimate of memory for the imprinting stimulus. Learning-related increases in amounts of the following proteins were found in the left IMM, but not the right IMM or the left or right PPN: (i) membrane cognin; (ii) a protein resembling the P32 subunit of splicing factor SF2; (iii) voltage-dependent anionic channel-1; (iv) dynamin-1; (v) heterogeneous nuclear ribonucleoprotein A2/B1. Learning-related increases in some transcription factors involved in mitochondrial biogenesis were also found, without significant change in mitochondrial DNA copy number. The results indicate that the molecular processes involved in learning and memory underlying imprinting include protein stabilization, increased mRNA trafficking, synaptic vesicle recycling, and specific changes in the mitochondrial proteome.
Collapse
Affiliation(s)
- Maia Meparishvili
- School of Natural Sciences and Engineering, Institute of Chemical Biology, Ilia State University Tbilisi, Georgia
| | - Maia Nozadze
- School of Natural Sciences and Engineering, Institute of Chemical Biology, Ilia State University Tbilisi, Georgia ; I. Beritashvili Institute of Experimental Biomedicine Tbilisi, Georgia
| | - Giorgi Margvelani
- School of Natural Sciences and Engineering, Institute of Chemical Biology, Ilia State University Tbilisi, Georgia
| | - Brian J McCabe
- Department of Zoology, Sub-Department of Animal Behavior, University of Cambridge Cambridge, UK
| | - Revaz O Solomonia
- School of Natural Sciences and Engineering, Institute of Chemical Biology, Ilia State University Tbilisi, Georgia ; I. Beritashvili Institute of Experimental Biomedicine Tbilisi, Georgia
| |
Collapse
|
11
|
Nair B, Johar K, Priya A, Wong-Riley MTT. Specificity protein 4 (Sp4) transcriptionally regulates inhibitory GABAergic receptors in neurons. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1863:1-9. [PMID: 26469128 DOI: 10.1016/j.bbamcr.2015.10.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 10/05/2015] [Accepted: 10/10/2015] [Indexed: 10/22/2022]
Abstract
Previous studies in our laboratory have shown that the neuron-specific specificity protein 4 (Sp4) transcriptionally regulates many excitatory neurotransmitter receptor subunit genes, such as those for GluN1, GluN2A, and GluN2B of N-methyl-d-aspartate (NMDA) receptors and Gria2 of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. It also regulates Atp1a1 and Atp1b1 subunit genes of Na(+)/K(+)-ATPase, a major energy-consuming enzyme, as well as all 13 subunits of cytochrome c oxidase (COX), an important energy-generating enzyme. Thus, there is a tight coupling between energy consumption, energy production, and excitatory neuronal activity at the transcriptional level in neurons. The question is whether inhibitory neurotransmitter receptors are also regulated by Sp4. In the present study, we tested our hypothesis that Sp4 regulates receptor subunit genes of a major inhibitory neurotransmitter, GABA, specifically GABAA receptors. By means of multiple approaches, including in silico analysis, electrophoretic mobility shift and supershift assays, real-time quantitative PCR, chromatin immunoprecipitation, promoter mutational analysis, over-expression and shRNA of Sp4, functional assays, and western blots, we found that Sp4 functionally regulates the transcription of Gabra1 (GABAA α1) and Gabra2 (GABAA α2), but not Gabra3 (GABAA α3) subunit genes. The binding sites of Sp4 are conserved among rats, humans, and mice. Thus, our results substantiate our hypothesis that Sp4 plays a key role in regulating the transcription of GABAA receptor subunit genes. They also indicate that Sp4 is in a position to transcriptionally regulate the balance between excitatory and inhibitory neurochemical expressions in neurons.
Collapse
Affiliation(s)
- Bindu Nair
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Kaid Johar
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Anusha Priya
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Margaret T T Wong-Riley
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
| |
Collapse
|
12
|
Bahat A, Perlberg S, Melamed-Book N, Isaac S, Eden A, Lauria I, Langer T, Orly J. Transcriptional activation of LON Gene by a new form of mitochondrial stress: A role for the nuclear respiratory factor 2 in StAR overload response (SOR). Mol Cell Endocrinol 2015; 408:62-72. [PMID: 25724481 DOI: 10.1016/j.mce.2015.02.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 02/19/2015] [Accepted: 02/19/2015] [Indexed: 01/19/2023]
Abstract
High output of steroid hormone synthesis in steroidogenic cells of the adrenal cortex and the gonads requires the expression of the steroidogenic acute regulatory protein (StAR) that facilitates cholesterol mobilization to the mitochondrial inner membrane where the CYP11A1/P450scc enzyme complex converts the sterol to the first steroid. Earlier studies have shown that StAR is active while pausing on the cytosolic face of the outer mitochondrial membrane while subsequent import of the protein into the matrix terminates the cholesterol mobilization activity. Consequently, during repeated activity cycles, high level of post-active StAR accumulates in the mitochondrial matrix. To prevent functional damage due to such protein overload effect, StAR is degraded by a sequence of three to four ATP-dependent proteases of the mitochondria protein quality control system, including LON and the m-AAA membranous proteases AFG3L2 and SPG7/paraplegin. Furthermore, StAR expression in both peri-ovulatory ovarian cells, or under ectopic expression in cell line models, results in up to 3-fold enrichment of the mitochondrial proteases and their transcripts. We named this novel form of mitochondrial stress as StAR overload response (SOR). To better understand the SOR mechanism at the transcriptional level we analyzed first the unexplored properties of the proximal promoter of the LON gene. Our findings suggest that the human nuclear respiratory factor 2 (NRF-2), also known as GA binding protein (GABP), is responsible for 88% of the proximal promoter activity, including the observed increase of transcription in the presence of StAR. Further studies are expected to reveal if common transcriptional determinants coordinate the SOR induced transcription of all the genes encoding the SOR proteases.
Collapse
Affiliation(s)
- Assaf Bahat
- Department of Biological Chemistry at the Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Shira Perlberg
- Department of Biological Chemistry at the Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Naomi Melamed-Book
- Bio-Imaging Unit at the Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Sara Isaac
- Department of Cell & Developmental Biology at the Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Amir Eden
- Department of Cell & Developmental Biology at the Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Ines Lauria
- CECAD Research Center, Institute for Genetics, University of Cologne, 50931 Cologne, Germany
| | - Thomas Langer
- CECAD Research Center, Institute for Genetics, University of Cologne, 50931 Cologne, Germany
| | - Joseph Orly
- Department of Biological Chemistry at the Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| |
Collapse
|
13
|
Bharadwaj R, Peter CJ, Jiang Y, Roussos P, Vogel-Ciernia A, Shen EY, Mitchell AC, Mao W, Whittle C, Dincer A, Jakovcevski M, Pothula V, Rasmussen TP, Giakoumaki SG, Bitsios P, Sherif A, Gardner PD, Ernst P, Ghose S, Sklar P, Haroutunian V, Tamminga C, Myers RH, Futai K, Wood MA, Akbarian S. Conserved higher-order chromatin regulates NMDA receptor gene expression and cognition. Neuron 2014; 84:997-1008. [PMID: 25467983 PMCID: PMC4258154 DOI: 10.1016/j.neuron.2014.10.032] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2014] [Indexed: 12/17/2022]
Abstract
Three-dimensional chromosomal conformations regulate transcription by moving enhancers and regulatory elements into spatial proximity with target genes. Here we describe activity-regulated long-range loopings bypassing up to 0.5 Mb of linear genome to modulate NMDA glutamate receptor GRIN2B expression in human and mouse prefrontal cortex. Distal intronic and 3' intergenic loop formations competed with repressor elements to access promoter-proximal sequences, and facilitated expression via a "cargo" of AP-1 and NRF-1 transcription factors and TALE-based transcriptional activators. Neuronal deletion or overexpression of Kmt2a/Mll1 H3K4- and Kmt1e/Setdb1 H3K9-methyltransferase was associated with higher-order chromatin changes at distal regulatory Grin2b sequences and impairments in working memory. Genetic polymorphisms and isogenic deletions of loop-bound sequences conferred liability for cognitive performance and decreased GRIN2B expression. Dynamic regulation of chromosomal conformations emerges as a novel layer for transcriptional mechanisms impacting neuronal signaling and cognition.
Collapse
Affiliation(s)
- Rahul Bharadwaj
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Cyril J Peter
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yan Jiang
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Panos Roussos
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Institute for Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; James J. Peters Veterans Affairs Medical Center, Bronx, New York, NY 10468, USA
| | - Annie Vogel-Ciernia
- Department of Neurobiology and Behavior, University of California at Irvine, Irvine, CA 92697, USA
| | - Erica Y Shen
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Amanda C Mitchell
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Wenjie Mao
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Catheryne Whittle
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Aslihan Dincer
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | | | - Venu Pothula
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Theodore P Rasmussen
- Department of Pharmaceutical Sciences and U.Conn Stem Cell Institute, University of Connecticut, Storrs, CT 06269, USA
| | - Stella G Giakoumaki
- Department of Psychiatry, University of Crete, 71003 Iraklion, Greece; Department of Psychology, University of Crete, 71003 Iraklion, Greece
| | - Panos Bitsios
- Computational Medicine Laboratory, Institute of Computer Science, Foundation for Research and Technology Hellas, 71003 Iraklion, Greece; Department of Psychiatry, University of Crete, 71003 Iraklion, Greece
| | - Ajfar Sherif
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Paul D Gardner
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Patricia Ernst
- Department of Genetics and Department of Microbiology and Immunology, Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Subroto Ghose
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Pamela Sklar
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Institute for Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Vahram Haroutunian
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; James J. Peters Veterans Affairs Medical Center, Bronx, New York, NY 10468, USA
| | - Carol Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Richard H Myers
- Department of Neurology, Boston University, Boston, MA 02118, USA
| | - Kensuke Futai
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Marcelo A Wood
- Department of Neurobiology and Behavior, University of California at Irvine, Irvine, CA 92697, USA
| | - Schahram Akbarian
- Friedman Brain Institute and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| |
Collapse
|
14
|
Nuclear respiratory factor 2 regulates the transcription of AMPA receptor subunit GluA2 (Gria2). BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:3018-28. [PMID: 25245478 DOI: 10.1016/j.bbamcr.2014.09.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 08/21/2014] [Accepted: 09/05/2014] [Indexed: 11/22/2022]
Abstract
Neuronal activity is highly dependent on energy metabolism. Nuclear respiratory factor 2 (NRF-2) tightly couples neuronal activity and energy metabolism by transcriptionally co-regulating all 13 subunits of an important energy-generating enzyme, cytochrome c oxidase (COX), as well as critical subunits of excitatory NMDA receptors. AMPA receptors are another major class of excitatory glutamatergic receptors that mediate most of the fast excitatory synaptic transmission in the brain. They are heterotetrameric proteins composed of various combinations of GluA1-4 subunits, with GluA2 being the most common one. We have previously shown that GluA2 (Gria2) is transcriptionally regulated by nuclear respiratory factor 1 (NRF-1) and specificity protein 4 (Sp4), which also regulate all subunits of COX. However, it was not known if NRF-2 also couples neuronal activity and energy metabolism by regulating subunits of the AMPA receptors. By means of multiple approaches, including electrophoretic mobility shift and supershift assays, chromatin immunoprecipitation, promoter mutations, real-time quantitative PCR, and western blot analysis, NRF-2 was found to functionally regulate the expression of Gria2, but not of Gria1, Gria3, or Gria4 genes in neurons. By regulating the GluA2 subunit of the AMPA receptor, NRF-2 couples energy metabolism and neuronal activity at the transcriptional level through a concurrent and parallel mechanism with NRF-1 and Sp4.
Collapse
|
15
|
Priya A, Johar K, Nair B, Wong-Riley MTT. Specificity protein 4 (Sp4) regulates the transcription of AMPA receptor subunit GluA2 (Gria2). BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:1196-206. [PMID: 24576410 DOI: 10.1016/j.bbamcr.2014.02.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 02/14/2014] [Accepted: 02/17/2014] [Indexed: 11/24/2022]
Abstract
The alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors are important glutamatergic receptors mediating fast excitatory synaptic transmission in the brain. The regulation of the four subunits of AMPA receptors, GluA1-4, is poorly understood. Excitatory synaptic transmission is highly energy-demanding, and this energy is derived mainly from the oxidative pathway. Recently, we found that specificity factor regulates all subunits of cytochrome c oxidase (COX), a critical energy-generating enzyme. COX is also regulated by nuclear respiratory factor 1 (NRF-1), which transcriptionally controls the Gria2 (GluA2) gene of AMPA receptors. The goal of the present study was to test our hypothesis that Sp-factors (Sp1, Sp3, and/or Sp4) also regulate AMPA subunit genes. If so, we wish to determine if Sp-factors and NRF-1 function via a complementary, concurrent and parallel, or a combination of complementary and concurrent/parallel mechanism. By means of multiple approaches, including electrophoretic mobility shift and supershift assays, chromatin immunoprecipitation, promoter mutations, real-time quantitative PCR, and western blot analysis, we found that Sp4, but not Sp1 or Sp3, regulates the Gria2, but not Gria1, 3, or 4, subunit gene of the AMPA receptor in a concurrent and parallel manner with NRF-1. Thus, Sp4 and NRF-1 both mediate the tight coupling between neuronal activity and energy metabolism at the transcriptional level.
Collapse
Affiliation(s)
- Anusha Priya
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Kaid Johar
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Bindu Nair
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Margaret T T Wong-Riley
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
| |
Collapse
|
16
|
Johar K, Priya A, Wong-Riley MTT. Regulation of Na(+)/K(+)-ATPase by neuron-specific transcription factor Sp4: implication in the tight coupling of energy production, neuronal activity and energy consumption in neurons. Eur J Neurosci 2013; 39:566-78. [PMID: 24219545 DOI: 10.1111/ejn.12415] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 10/03/2013] [Accepted: 10/07/2013] [Indexed: 12/24/2022]
Abstract
A major source of energy demand in neurons is the Na(+)/K(+)-ATPase pump that restores the ionic gradient across the plasma membrane subsequent to depolarizing neuronal activity. The energy comes primarily from mitochondrial oxidative metabolism, of which cytochrome c oxidase (COX) is a key enzyme. Recently, we found that all 13 subunits of COX are regulated by specificity (Sp) factors, and that the neuron-specific Sp4, but not Sp1 or Sp3, regulates the expression of key glutamatergic receptor subunits as well. The present study sought to test our hypothesis that Sp4 also regulates Na(+)/K(+)-ATPase subunit genes in neurons. By means of multiple approaches, including in silico analysis, electrophoretic mobility shift and supershift assays, chromatin immunoprecipitation, promoter mutational analysis, over-expression, and RNA interference studies, we found that Sp4, with minor contributions from Sp1 and Sp3, functionally regulate the Atp1a1, Atp1a3, and Atp1b1 subunit genes of Na(+)/K(+)-ATPase in neurons. Transcripts of all three genes were up-regulated by depolarizing KCl stimulation and down-regulated by the impulse blocker tetrodotoxin (TTX), indicating that their expression was activity-dependent. Silencing of Sp4 blocked the up-regulation of these genes induced by KCl, whereas over-expression of Sp4 rescued them from TTX-induced suppression. The effect of silencing or over-expressing Sp4 on primary neurons was much greater than those of Sp1 or Sp3. The binding sites of Sp factors on these genes are conserved among mice, rats and humans. Thus, Sp4 plays an important role in the transcriptional coupling of energy generation and energy consumption in neurons.
Collapse
Affiliation(s)
- Kaid Johar
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA
| | | | | |
Collapse
|
17
|
Johar K, Priya A, Dhar S, Liu Q, Wong-Riley MTT. Neuron-specific specificity protein 4 bigenomically regulates the transcription of all mitochondria- and nucleus-encoded cytochrome c oxidase subunit genes in neurons. J Neurochem 2013; 127:496-508. [PMID: 24032355 DOI: 10.1111/jnc.12433] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 08/20/2013] [Accepted: 08/21/2013] [Indexed: 12/20/2022]
Abstract
Neurons are highly dependent on oxidative metabolism for their energy supply, and cytochrome c oxidase (COX) is a key energy-generating enzyme in the mitochondria. A unique feature of COX is that it is one of only four proteins in mammalian cells that are bigenomically regulated. Of its thirteen subunits, three are encoded in the mitochondrial genome and ten are nuclear-encoded on nine different chromosomes. The mechanism of regulating this multisubunit, bigenomic enzyme poses a distinct challenge. In recent years, we found that nuclear respiratory factors 1 and 2 (NRF-1 and NRF-2) mediate such bigenomic coordination. The latest candidate is the specificity factor (Sp) family of proteins. In N2a cells, we found that Sp1 regulates all 13 COX subunits. However, we discovered recently that in primary neurons, it is Sp4 and not Sp1 that regulates some of the key glutamatergic receptor subunit genes. The question naturally arises as to the role of Sp4 in regulating COX in primary neurons. The present study utilized multiple approaches, including chromatin immunoprecipitation, promoter mutational analysis, knockdown and over-expression of Sp4, as well as functional assays to document that Sp4 indeed functionally regulate all 13 subunits of COX as well as mitochondrial transcription factors A and B. The present study discovered that among the specificity family of transcription factors, it is the less known neuron-specific Sp4 that regulates the expression of all 13 subunits of mitochondrial cytochrome c oxidase (COX) enzyme in primary neurons. Sp4 also regulates the three mitochondrial transcription factors (TFAM, TFB1M, and TFB2M) and a COX assembly protein SURF-1 in primary neurons.
Collapse
Affiliation(s)
- Kaid Johar
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | | | | | | | | |
Collapse
|
18
|
Priya A, Johar K, Wong-Riley MTT. Specificity protein 4 functionally regulates the transcription of NMDA receptor subunits GluN1, GluN2A, and GluN2B. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:2745-2756. [PMID: 23871830 DOI: 10.1016/j.bbamcr.2013.07.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/03/2013] [Accepted: 07/08/2013] [Indexed: 10/26/2022]
Abstract
N-Methyl-d-aspartate (NMDA) receptors are major glutamatergic receptors involved in most excitatory neurotransmission in the brain. The transcriptional regulation of NMDA receptors is not fully understood. Previously, we found that the GluN1 and GluN2B subunits of the NMDA receptor are regulated by nuclear respiratory factors 1 and 2 (NRF-1 and NRF-2). NRF-1 and NRF-2 also regulate all 13 subunits of cytochrome c oxidase (COX), a critical energy-generating enzyme, thereby coupling neuronal activity and energy metabolism at the transcriptional level. Specificity protein (Sp) is a family of transcription factors that bind to GC-rich regions, with Sp1, Sp3, and Sp4 all binding to the same cis- motifs. Sp1 and Sp3 are ubiquitously expressed, whereas Sp4 expression is restricted to neurons and testicular cells. Recently, we found that the Sp1 factor regulates all subunits of COX. The goal of the present study was to test our hypothesis that the Sp factors also regulate specific subunits of NMDA receptors, and that they function with NRF-1 and NRF-2 via one of three mechanisms: complementary, concurrent and parallel, or a combination of complementary and concurrent/parallel. By means of multiple approaches we found that Sp4 functionally regulated GluN1, GluN2A, and GluN2B, but not GluN2C. On the other hand, Sp1 and Sp3 did not regulate these subunits as previously thought. Our data suggest that Sp4 operates in a complementary and concurrent/parallel manner with NRF-1 and NRF-2 to mediate the tight coupling between energy metabolism and neuronal activity at the molecular level.
Collapse
Affiliation(s)
- Anusha Priya
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Kaid Johar
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Margaret T T Wong-Riley
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
| |
Collapse
|
19
|
Dhar SS, Johar K, Wong-Riley MTT. Bigenomic transcriptional regulation of all thirteen cytochrome c oxidase subunit genes by specificity protein 1. Open Biol 2013; 3:120176. [PMID: 23516108 PMCID: PMC3718336 DOI: 10.1098/rsob.120176] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cytochrome c oxidase (COX) is one of only four known bigenomic proteins, with three mitochondria-encoded subunits and 10 nucleus-encoded ones derived from nine different chromosomes. The mechanism of regulating this multi-subunit, bigenomic enzyme is not fully understood. We hypothesize that specificity protein 1 (Sp1) functionally regulates the 10 nucleus-encoded COX subunit genes directly and the three mitochondrial COX subunit genes indirectly by regulating mitochondrial transcription factors A and B (TFAM, TFB1M and TFB2M) in neurons. By means of in silico analysis, electrophoretic mobility shift and supershift assays, chromatin immunoprecipitation, RNA interference and over-expression experiments, the present study documents that Sp1 is a critical regulator of all 13 COX subunit genes in neurons. This regulation is intimately associated with neuronal activity. Silencing of Sp1 prevented the upregulation of all COX subunits by KCl, and over-expressing Sp1 rescued all COX subunits from being downregulated by tetrodotoxin. Thus, Sp1 and our previously described nuclear respiratory factors 1 and 2 are the three key regulators of all 13 COX subunit genes in neurons. The binding sites for Sp1 on all 10 nucleus-encoded COX subunits, TFAM, TFB1M and TFB2M are highly conserved among mice, rats and humans.
Collapse
Affiliation(s)
- Shilpa S Dhar
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | | | | |
Collapse
|