Contact
Biomedical Research Center251 Bayview Boulevard
Suite 200
Baltimore, MD 21224
Email: emily.simonswires@nih.gov
Education
Ph.D. – University of Maryland, Baltimore
Research Interests
Emily received her Ph.D. in November 2016 from University of Maryland, Baltimore. Her dissertation focused on the effects of dietary intake on endoplasmic reticulum homeostasis. Her research focuses on the endoplasmic reticulum (ER) stress, specifically protein homeostasis in the context of ER calcium depletion in response to pharmacological and physiological stressors. Following graduate school, she had a joint postdoctoral appointment between NINR and NIDA, where she studied protein homeostasis in ryanodine receptor 1- related myopathies. Now currently at NIDA, her research stems from an identified subset of endogenous, human proteins secreted in response to ER calcium depletion- a phenomenon coined “exodosis.” The goal is to exploit this finding towards the generation of clinical biomarkers reflective of ER calcium depletion. Emily is also investigating the contribution of KDEL receptors in maintaining protein homeostasis. KDEL receptors are relatively understudied and responsible for retaining ER-resident chaperone proteins, thus integral to the ER and Golgi dynamic.
In addition to her time at the bench, Emily mentors young scientists and serves on many institutional committees. She is also the recipient of multiple grants and has been invited to speak at international conferences.
Publications
Selected Publications
2020
Lawal, Tokunbor A; Wires, Emily S; Terry, Nancy L; Dowling, James J; Todd, Joshua J
In: Orphanet Journal of Rare Diseases, vol. 15, no. 1, pp. 113, 2020, ISBN: 1750-1172.
@article{Lawal:2020aa,
title = {Preclinical model systems of ryanodine receptor 1-related myopathies and malignant hyperthermia: a comprehensive scoping review of works published 1990--2019},
author = {Tokunbor A Lawal and Emily S Wires and Nancy L Terry and James J Dowling and Joshua J Todd},
url = {https://pubmed.ncbi.nlm.nih.gov/32381029/},
doi = {10.1186/s13023-020-01384-x},
isbn = {1750-1172},
year = {2020},
date = {2020-01-01},
journal = {Orphanet Journal of Rare Diseases},
volume = {15},
number = {1},
pages = {113},
abstract = {Pathogenic variations in the gene encoding the skeletal muscle ryanodine receptor (RyR1) are associated with malignant hyperthermia (MH) susceptibility, a life-threatening hypermetabolic condition and RYR1-related myopathies (RYR1-RM), a spectrum of rare neuromuscular disorders. In RYR1-RM, intracellular calcium dysregulation, post-translational modifications, and decreased protein expression lead to a heterogenous clinical presentation including proximal muscle weakness, contractures, scoliosis, respiratory insufficiency, and ophthalmoplegia. Preclinical model systems of RYR1-RM and MH have been developed to better understand underlying pathomechanisms and test potential therapeutics.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Pathogenic variations in the gene encoding the skeletal muscle ryanodine receptor (RyR1) are associated with malignant hyperthermia (MH) susceptibility, a life-threatening hypermetabolic condition and RYR1-related myopathies (RYR1-RM), a spectrum of rare neuromuscular disorders. In RYR1-RM, intracellular calcium dysregulation, post-translational modifications, and decreased protein expression lead to a heterogenous clinical presentation including proximal muscle weakness, contractures, scoliosis, respiratory insufficiency, and ophthalmoplegia. Preclinical model systems of RYR1-RM and MH have been developed to better understand underlying pathomechanisms and test potential therapeutics.
2018
Anttila, Jenni E; Albert, Katrina; Wires, Emily S; Mätlik, Kert; Loram, Lisa C; Watkins, Linda R; Rice, Kenner C; Wang, Yun; Harvey, Brandon K; Airavaara, Mikko
Post-stroke Intranasal (+)-Naloxone Delivery Reduces Microglial Activation and Improves Behavioral Recovery from Ischemic Injury Journal Article
In: eNeuro, vol. 5, no. 2, 2018.
@article{AnttilaENEURO.0395-17.2018,
title = {Post-stroke Intranasal (+)-Naloxone Delivery Reduces Microglial Activation and Improves Behavioral Recovery from Ischemic Injury},
author = {Jenni E Anttila and Katrina Albert and Emily S Wires and Kert Mätlik and Lisa C Loram and Linda R Watkins and Kenner C Rice and Yun Wang and Brandon K Harvey and Mikko Airavaara},
url = {https://pubmed.ncbi.nlm.nih.gov/29766045/},
doi = {10.1523/ENEURO.0395-17.2018},
year = {2018},
date = {2018-01-01},
journal = {eNeuro},
volume = {5},
number = {2},
publisher = {Society for Neuroscience},
abstract = {Ischemic stroke is the leading cause of disability, and effective therapeutic strategies are needed to promote complete recovery. Neuroinflammation plays a significant role in stroke pathophysiology, and there is limited understanding of how it affects recovery. The aim of this study was to characterize the spatiotemporal expression profile of microglial activation and whether dampening microglial/macrophage activation post-stroke facilitates the recovery. For dampening microglial/macrophage activation, we chose intranasal administration of naloxone, a drug that is already in clinical use for opioid overdose and is known to decrease microglia/macrophage activation. We characterized the temporal progression of microglia/macrophage activation following cortical ischemic injury in rat and found the peak activation in cortex 7 d post-stroke. Unexpectedly, there was a chronic expression of phagocytic cells in the thalamus associated with neuronal loss. (+)-Naloxone, an enantiomer that reduces microglial activation without antagonizing opioid receptors, was administered intranasally starting 1 d post-stroke and continuing for 7 d. (+)-Naloxone treatment decreased microglia/macrophage activation in the striatum and thalamus, promoted behavioral recovery during the 14-d monitoring period, and reduced neuronal death in the lesioned cortex and ipsilateral thalamus. Our results are the first to show that post-stroke intranasal (+)-naloxone administration promotes short-term functional recovery and reduces microglia/macrophage activation. Therefore, (+)-naloxone is a promising drug for the treatment of ischemic stroke, and further studies should be conducted.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Ischemic stroke is the leading cause of disability, and effective therapeutic strategies are needed to promote complete recovery. Neuroinflammation plays a significant role in stroke pathophysiology, and there is limited understanding of how it affects recovery. The aim of this study was to characterize the spatiotemporal expression profile of microglial activation and whether dampening microglial/macrophage activation post-stroke facilitates the recovery. For dampening microglial/macrophage activation, we chose intranasal administration of naloxone, a drug that is already in clinical use for opioid overdose and is known to decrease microglia/macrophage activation. We characterized the temporal progression of microglia/macrophage activation following cortical ischemic injury in rat and found the peak activation in cortex 7 d post-stroke. Unexpectedly, there was a chronic expression of phagocytic cells in the thalamus associated with neuronal loss. (+)-Naloxone, an enantiomer that reduces microglial activation without antagonizing opioid receptors, was administered intranasally starting 1 d post-stroke and continuing for 7 d. (+)-Naloxone treatment decreased microglia/macrophage activation in the striatum and thalamus, promoted behavioral recovery during the 14-d monitoring period, and reduced neuronal death in the lesioned cortex and ipsilateral thalamus. Our results are the first to show that post-stroke intranasal (+)-naloxone administration promotes short-term functional recovery and reduces microglia/macrophage activation. Therefore, (+)-naloxone is a promising drug for the treatment of ischemic stroke, and further studies should be conducted.
2017
Wires, Emily S; Trychta, Kathleen A; Back, Susanne; Sulima, Agnieszka; Rice, Kenner C; Harvey, Brandon K
High fat diet disrupts endoplasmic reticulum calcium homeostasis in the rat liver. Journal Article
In: J Hepatol, vol. 67, no. 5, pp. 1009–1017, 2017, ISSN: 1600-0641 (Electronic); 0168-8278 (Linking).
@article{cite-key,
title = {High fat diet disrupts endoplasmic reticulum calcium homeostasis in the rat liver.},
author = {Emily S Wires and Kathleen A Trychta and Susanne Back and Agnieszka Sulima and Kenner C Rice and Brandon K Harvey},
url = {https://www.ncbi.nlm.nih.gov/pubmed/28596111},
doi = {10.1016/j.jhep.2017.05.023},
issn = {1600-0641 (Electronic); 0168-8278 (Linking)},
year = {2017},
date = {2017-07-17},
urldate = {2017-07-17},
journal = {J Hepatol},
volume = {67},
number = {5},
pages = {1009--1017},
address = {Molecular Mechanisms of Cellular Stress and Inflammation Unit, Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD 21224, USA.},
abstract = {BACKGROUND & AIMS: Disruption to endoplasmic reticulum (ER) calcium homeostasis has been implicated in obesity, however, the ability to longitudinally monitor ER calcium fluctuations has been challenging with prior methodologies. We recently described the development of a Gaussia luciferase (GLuc)-based reporter protein responsive to ER calcium depletion (GLuc-SERCaMP) and investigated the effect of a high fat diet on ER calcium homeostasis. METHODS: A GLuc-based reporter cell line was treated with palmitate, a free fatty acid. Rats intrahepatically injected with GLuc-SERCaMP reporter were fed a cafeteria diet or high fat diet. The liver and plasma were examined for established markers of steatosis and compared to plasma levels of SERCaMP activity. RESULTS: Palmitate induced GLuc-SERCaMP release in vitro, indicating ER calcium depletion. Consumption of a cafeteria diet or high fat pellets correlated with alterations to hepatic ER calcium homeostasis in rats, shown by increased GLuc-SERCaMP release. Access to ad lib high fat pellets also led to a corresponding decrease in microsomal calcium ATPase activity and an increase in markers of hepatic steatosis. In addition to GLuc-SERCaMP, we have also identified endogenous proteins (endogenous SERCaMPs) with a similar response to ER calcium depletion. We demonstrated the release of an endogenous SERCaMP, thought to be a liver esterase, during access to a high fat diet. Attenuation of both GLuc-SERCaMP and endogenous SERCaMP was observed during dantrolene administration. CONCLUSIONS: Here we describe the use of a reporter for in vitro and in vivo models of high fat diet. Our results support the theory that dietary fat intake correlates with a decrease in ER calcium levels in the liver and suggest a high fat diet alters the ER proteome. Lay summary: ER calcium dysregulation was observed in rats fed a cafeteria diet or high fat pellets, with fluctuations in sensor release correlating with fat intake. Attenuation of sensor release, as well as food intake was observed during administration of dantrolene, a drug that stabilizes ER calcium. The study describes a novel technique for liver research and provides insight into cellular processes that may contribute to the pathogenesis of obesity and fatty liver disease.},
keywords = {},
pubstate = {published},
tppubtype = {article}
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BACKGROUND & AIMS: Disruption to endoplasmic reticulum (ER) calcium homeostasis has been implicated in obesity, however, the ability to longitudinally monitor ER calcium fluctuations has been challenging with prior methodologies. We recently described the development of a Gaussia luciferase (GLuc)-based reporter protein responsive to ER calcium depletion (GLuc-SERCaMP) and investigated the effect of a high fat diet on ER calcium homeostasis. METHODS: A GLuc-based reporter cell line was treated with palmitate, a free fatty acid. Rats intrahepatically injected with GLuc-SERCaMP reporter were fed a cafeteria diet or high fat diet. The liver and plasma were examined for established markers of steatosis and compared to plasma levels of SERCaMP activity. RESULTS: Palmitate induced GLuc-SERCaMP release in vitro, indicating ER calcium depletion. Consumption of a cafeteria diet or high fat pellets correlated with alterations to hepatic ER calcium homeostasis in rats, shown by increased GLuc-SERCaMP release. Access to ad lib high fat pellets also led to a corresponding decrease in microsomal calcium ATPase activity and an increase in markers of hepatic steatosis. In addition to GLuc-SERCaMP, we have also identified endogenous proteins (endogenous SERCaMPs) with a similar response to ER calcium depletion. We demonstrated the release of an endogenous SERCaMP, thought to be a liver esterase, during access to a high fat diet. Attenuation of both GLuc-SERCaMP and endogenous SERCaMP was observed during dantrolene administration. CONCLUSIONS: Here we describe the use of a reporter for in vitro and in vivo models of high fat diet. Our results support the theory that dietary fat intake correlates with a decrease in ER calcium levels in the liver and suggest a high fat diet alters the ER proteome. Lay summary: ER calcium dysregulation was observed in rats fed a cafeteria diet or high fat pellets, with fluctuations in sensor release correlating with fat intake. Attenuation of sensor release, as well as food intake was observed during administration of dantrolene, a drug that stabilizes ER calcium. The study describes a novel technique for liver research and provides insight into cellular processes that may contribute to the pathogenesis of obesity and fatty liver disease.
Wires, Emily S; Henderson, Mark J; Yan, Xiaokang; Bäck, Susanne; Trychta, Kathleen A; Lutrey, Molly H; Harvey, Brandon K
Longitudinal monitoring of Gaussia and Nano luciferase activities to concurrently assess ER calcium homeostasis and ER stress in vivo Journal Article
In: PLOS ONE, vol. 12, no. 4, pp. 1-17, 2017.
@article{10.1371/journal.pone.0175481,
title = {Longitudinal monitoring of Gaussia and Nano luciferase activities to concurrently assess ER calcium homeostasis and ER stress in vivo},
author = {Emily S Wires and Mark J Henderson and Xiaokang Yan and Susanne Bäck and Kathleen A Trychta and Molly H Lutrey and Brandon K Harvey},
url = {https://pubmed.ncbi.nlm.nih.gov/28403212/},
doi = {10.1371/journal.pone.0175481},
year = {2017},
date = {2017-01-01},
urldate = {2017-01-01},
journal = {PLOS ONE},
volume = {12},
number = {4},
pages = {1-17},
publisher = {Public Library of Science},
abstract = {The endoplasmic reticulum (ER) is essential to many cellular processes including protein processing, lipid metabolism and calcium storage. The ability to longitudinally monitor ER homeostasis in the same organism would offer insight into progressive molecular and cellular adaptations to physiologic or pathologic states, but has been challenging. We recently described the creation of a Gaussia luciferase (GLuc)-based secreted ER calcium-modulated protein (SERCaMP or GLuc-SERCaMP) to longitudinally monitor ER calcium homeostasis. Here we describe a complementary tool to measure the unfolded protein response (UPR), utilizing a UPRE-driven secreted Nano luciferase (UPRE-secNLuc) to examine the activating transcription factor-6 (ATF6) and inositol-requiring enzyme 1 (IRE1) pathways of the UPR. We observed an upregulation of endogenous ATF6- and XBP1-regulated genes following pharmacologically-induced ER stress that was consistent with responsiveness of the UPRE sensor. Both GLuc and NLuc-based reporters have favorable properties for in vivo studies, however, they are not easily used in combination due to overlapping substrate activities. We describe a method to measure the enzymatic activities of both reporters from a single sample and validated the approach using culture medium and rat blood samples to measure GLuc-SERCaMP and UPRE-secNLuc. Measuring GLuc and NLuc activities from the same sample allows for the robust and quantitative measurement of two cellular events or cell populations from a single biological sample. This study is the first to describe the in vivo measurement of UPRE activation by sampling blood, using an approach that allows concurrent interrogation of two components of ER homeostasis.},
keywords = {},
pubstate = {published},
tppubtype = {article}
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The endoplasmic reticulum (ER) is essential to many cellular processes including protein processing, lipid metabolism and calcium storage. The ability to longitudinally monitor ER homeostasis in the same organism would offer insight into progressive molecular and cellular adaptations to physiologic or pathologic states, but has been challenging. We recently described the creation of a Gaussia luciferase (GLuc)-based secreted ER calcium-modulated protein (SERCaMP or GLuc-SERCaMP) to longitudinally monitor ER calcium homeostasis. Here we describe a complementary tool to measure the unfolded protein response (UPR), utilizing a UPRE-driven secreted Nano luciferase (UPRE-secNLuc) to examine the activating transcription factor-6 (ATF6) and inositol-requiring enzyme 1 (IRE1) pathways of the UPR. We observed an upregulation of endogenous ATF6- and XBP1-regulated genes following pharmacologically-induced ER stress that was consistent with responsiveness of the UPRE sensor. Both GLuc and NLuc-based reporters have favorable properties for in vivo studies, however, they are not easily used in combination due to overlapping substrate activities. We describe a method to measure the enzymatic activities of both reporters from a single sample and validated the approach using culture medium and rat blood samples to measure GLuc-SERCaMP and UPRE-secNLuc. Measuring GLuc and NLuc activities from the same sample allows for the robust and quantitative measurement of two cellular events or cell populations from a single biological sample. This study is the first to describe the in vivo measurement of UPRE activation by sampling blood, using an approach that allows concurrent interrogation of two components of ER homeostasis.
Anttila, Jenni E; Whitaker, Keith W; Wires, Emily S; Harvey, Brandon K; Airavaara, Mikko
Role of microglia in ischemic focal stroke and recovery: focus on Toll-like receptors Journal Article
In: Progress in Neuro-Psychopharmacology and Biological Psychiatry, vol. 79, pp. 3-14, 2017, ISSN: 0278-5846, (Roles of the immune system in mediating plasticity of the brain and behaviour).
@article{ANTTILA20173,
title = {Role of microglia in ischemic focal stroke and recovery: focus on Toll-like receptors},
author = {Jenni E Anttila and Keith W Whitaker and Emily S Wires and Brandon K Harvey and Mikko Airavaara},
url = {https://pubmed.ncbi.nlm.nih.gov/27389423/},
doi = {https://doi.org/10.1016/j.pnpbp.2016.07.003},
issn = {0278-5846},
year = {2017},
date = {2017-01-01},
journal = {Progress in Neuro-Psychopharmacology and Biological Psychiatry},
volume = {79},
pages = {3-14},
abstract = {Stroke is the leading cause of disability in adults. Drug treatments that target stroke-induced pathological mechanisms and promote recovery are desperately needed. In the brain, an ischemic event triggers major inflammatory responses that are mediated by the resident microglial cells. In this review, we focus on the microglia activation after ischemic brain injury as a target of immunomodulatory therapeutics. We divide the microglia-mediated events following ischemic stroke into three categories: acute, subacute, and long-term events. This division encompasses the spatial and temporal dynamics of microglia as they participate in the pathophysiological changes that contribute to the symptoms and sequela of a stroke. The importance of Toll-like receptor (TLR) signaling in the outcomes of these pathophysiological changes is highlighted. Increasing evidence shows that microglia have a complex role in stroke pathophysiology, and they mediate both detrimental and beneficial effects on stroke outcome. So far, most of the pharmacological studies in experimental models of stroke have focused on neuroprotective strategies which are impractical for clinical applications. Post-ischemic inflammation is long lasting and thus, could provide a therapeutic target for novel delayed drug treatment. However, more studies are needed to elucidate the role of microglia in the recovery process from an ischemic stroke and to evaluate the therapeutic potential of modulating post-ischemic inflammation to promote functional recovery.},
note = {Roles of the immune system in mediating plasticity of the brain and behaviour},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Stroke is the leading cause of disability in adults. Drug treatments that target stroke-induced pathological mechanisms and promote recovery are desperately needed. In the brain, an ischemic event triggers major inflammatory responses that are mediated by the resident microglial cells. In this review, we focus on the microglia activation after ischemic brain injury as a target of immunomodulatory therapeutics. We divide the microglia-mediated events following ischemic stroke into three categories: acute, subacute, and long-term events. This division encompasses the spatial and temporal dynamics of microglia as they participate in the pathophysiological changes that contribute to the symptoms and sequela of a stroke. The importance of Toll-like receptor (TLR) signaling in the outcomes of these pathophysiological changes is highlighted. Increasing evidence shows that microglia have a complex role in stroke pathophysiology, and they mediate both detrimental and beneficial effects on stroke outcome. So far, most of the pharmacological studies in experimental models of stroke have focused on neuroprotective strategies which are impractical for clinical applications. Post-ischemic inflammation is long lasting and thus, could provide a therapeutic target for novel delayed drug treatment. However, more studies are needed to elucidate the role of microglia in the recovery process from an ischemic stroke and to evaluate the therapeutic potential of modulating post-ischemic inflammation to promote functional recovery.
2015
Henderson, Mark J AU -; Wires, Emily S AU -; Trychta, Kathleen A AU -; Yan, Xiaokang AU -; Harvey, Brandon K AU -
Monitoring Endoplasmic Reticulum Calcium Homeostasis Using a Gaussia Luciferase SERCaMP Journal Article
In: JoVE, no. 103, pp. e53199, 2015, ISBN: 1940-087X.
@article{AU---Henderson:2015aa,
title = {Monitoring Endoplasmic Reticulum Calcium Homeostasis Using a Gaussia Luciferase SERCaMP},
author = {Mark J AU - Henderson and Emily S AU - Wires and Kathleen A AU - Trychta and Xiaokang AU - Yan and Brandon K AU - Harvey},
url = {https://pubmed.ncbi.nlm.nih.gov/26383227/},
doi = {doi:10.3791/53199},
isbn = {1940-087X},
year = {2015},
date = {2015-01-01},
journal = {JoVE},
number = {103},
pages = {e53199},
publisher = {MyJoVE Corp},
abstract = {The endoplasmic reticulum (ER) contains the highest level of intracellular calcium, with concentrations approximately 5,000-fold greater than cytoplasmic levels. Tight control over ER calcium is imperative for protein folding, modification and trafficking. Perturbations to ER calcium can result in the activation of the unfolded protein response, a three-prong ER stress response mechanism, and contribute to pathogenesis in a variety of diseases. The ability to monitor ER calcium alterations during disease onset and progression is important in principle, yet challenging in practice. Currently available methods for monitoring ER calcium, such as calcium-dependent fluorescent dyes and proteins, have provided insight into ER calcium dynamics in cells, however these tools are not well suited for in vivo studies. Our lab has demonstrated that a modification to the carboxy-terminus of Gaussia luciferase confers secretion of the reporter in response to ER calcium depletion. The methods for using a luciferase based, secreted ER calcium monitoring protein (SERCaMP) for in vitro and in vivo applications are described herein. This video highlights hepatic injections, pharmacological manipulation of GLuc-SERCaMP, blood collection and processing, and assay parameters for longitudinal monitoring of ER calcium.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The endoplasmic reticulum (ER) contains the highest level of intracellular calcium, with concentrations approximately 5,000-fold greater than cytoplasmic levels. Tight control over ER calcium is imperative for protein folding, modification and trafficking. Perturbations to ER calcium can result in the activation of the unfolded protein response, a three-prong ER stress response mechanism, and contribute to pathogenesis in a variety of diseases. The ability to monitor ER calcium alterations during disease onset and progression is important in principle, yet challenging in practice. Currently available methods for monitoring ER calcium, such as calcium-dependent fluorescent dyes and proteins, have provided insight into ER calcium dynamics in cells, however these tools are not well suited for in vivo studies. Our lab has demonstrated that a modification to the carboxy-terminus of Gaussia luciferase confers secretion of the reporter in response to ER calcium depletion. The methods for using a luciferase based, secreted ER calcium monitoring protein (SERCaMP) for in vitro and in vivo applications are described herein. This video highlights hepatic injections, pharmacological manipulation of GLuc-SERCaMP, blood collection and processing, and assay parameters for longitudinal monitoring of ER calcium.
2014
Henderson, Mark J; Wires, Emily S; Trychta, Kathleen A; Richie, Christopher T; Harvey, Brandon K
SERCaMP: a carboxy-terminal protein modification that enables monitoring of ER calcium homeostasis. Journal Article
In: Mol Biol Cell, vol. 25, no. 18, pp. 2828–2839, 2014, ISSN: 1939-4586 (Electronic); 1059-1524 (Linking).
@article{Henderson2014,
title = {SERCaMP: a carboxy-terminal protein modification that enables monitoring of ER calcium homeostasis.},
author = {Mark J Henderson and Emily S Wires and Kathleen A Trychta and Christopher T Richie and Brandon K Harvey},
url = {https://www.ncbi.nlm.nih.gov/pubmed/25031430},
doi = {10.1091/mbc.E14-06-1141},
issn = {1939-4586 (Electronic); 1059-1524 (Linking)},
year = {2014},
date = {2014-07-16},
urldate = {2014-07-16},
journal = {Mol Biol Cell},
volume = {25},
number = {18},
pages = {2828--2839},
address = {Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD 21224.},
abstract = {Endoplasmic reticulum (ER) calcium homeostasis is disrupted in diverse pathologies, including neurodegeneration, cardiovascular diseases, and diabetes. Temporally defining calcium dysregulation during disease progression, however, has been challenging. Here we describe secreted ER calcium-monitoring proteins (SERCaMPs), which allow for longitudinal monitoring of ER calcium homeostasis. We identified a carboxy-terminal modification that is sufficient to confer release of a protein specifically in response to ER calcium depletion. A Gaussia luciferase (GLuc)-based SERCaMP provides a simple and sensitive method to monitor ER calcium homeostasis in vitro or in vivo by analyzing culture medium or blood. GLuc-SERCaMPs revealed ER calcium depletion in rat primary neurons exposed to various ER stressors. In vivo, ER calcium disruption in rat liver was monitored over several days by repeated sampling of blood. Our results suggest that SERCaMPs will have broad applications for the long-term monitoring of ER calcium homeostasis and the development of therapeutic approaches to counteract ER calcium dysregulation.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Endoplasmic reticulum (ER) calcium homeostasis is disrupted in diverse pathologies, including neurodegeneration, cardiovascular diseases, and diabetes. Temporally defining calcium dysregulation during disease progression, however, has been challenging. Here we describe secreted ER calcium-monitoring proteins (SERCaMPs), which allow for longitudinal monitoring of ER calcium homeostasis. We identified a carboxy-terminal modification that is sufficient to confer release of a protein specifically in response to ER calcium depletion. A Gaussia luciferase (GLuc)-based SERCaMP provides a simple and sensitive method to monitor ER calcium homeostasis in vitro or in vivo by analyzing culture medium or blood. GLuc-SERCaMPs revealed ER calcium depletion in rat primary neurons exposed to various ER stressors. In vivo, ER calcium disruption in rat liver was monitored over several days by repeated sampling of blood. Our results suggest that SERCaMPs will have broad applications for the long-term monitoring of ER calcium homeostasis and the development of therapeutic approaches to counteract ER calcium dysregulation.
2012
Wires, Emily S; Alvarez, David; Dobrowolski, Curtis; Wang, Yun; Morales, Marisela; Karn, Jonathan; Harvey, Brandon K
In: J Neurovirol, vol. 18, no. 5, pp. 400–410, 2012, ISSN: 1538-2443 (Electronic); 1355-0284 (Linking).
@article{Wires2012,
title = {Methamphetamine activates nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB) and induces human immunodeficiency virus (HIV) transcription in human microglial cells.},
author = {Emily S Wires and David Alvarez and Curtis Dobrowolski and Yun Wang and Marisela Morales and Jonathan Karn and Brandon K Harvey},
url = {https://www.ncbi.nlm.nih.gov/pubmed/22618514},
doi = {10.1007/s13365-012-0103-4},
issn = {1538-2443 (Electronic); 1355-0284 (Linking)},
year = {2012},
date = {2012-10-01},
urldate = {2012-10-01},
journal = {J Neurovirol},
volume = {18},
number = {5},
pages = {400--410},
address = {Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA.},
abstract = {Human immunodeficiency virus (HIV) primarily infects glial cells in the central nervous system (CNS). Recent evidence suggests that HIV-infected individuals who abuse drugs such as methamphetamine (METH) have higher viral loads and experience more severe neurological complications than HIV-infected individuals who do not abuse drugs. The aim of this study was to determine the effect of METH on HIV expression from the HIV long terminal repeat (LTR) promoter and on an HIV integrated provirus in microglial cells, the primary host cells for HIV in the CNS. Primary human microglial cells immortalized with SV40 T antigen (CHME-5 cells) were cotransfected with an HIV LTR reporter and the HIV Tat gene, a key regulator of viral replication and gene expression, and exposed to METH. Our results demonstrate that METH treatment induced LTR activation, an effect potentiated in the presence of Tat. We also found that METH increased the nuclear translocation of the nuclear factor kappa B (NF-kappaB), a key cellular transcriptional regulator of the LTR promoter, and the activity of an NF-kappaB-specific reporter plasmid in CHME-5 cells. The presence of a dominant-negative regulator of NF-kappaB blocked METH-related activation of the HIV LTR. Furthermore, treatment of HIV-latently infected CHME-5 (CHME-5/HIV) cells with METH induced HIV expression and nuclear translocation of the p65 subunit of NF-kappaB. These results suggest that METH can stimulate HIV gene expression in microglia cells through activation of the NF-kappaB signaling pathway. This mechanism may outline the initial biochemical events leading to the observed increased neurodegeneration in HIV-positive individuals who use METH.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Human immunodeficiency virus (HIV) primarily infects glial cells in the central nervous system (CNS). Recent evidence suggests that HIV-infected individuals who abuse drugs such as methamphetamine (METH) have higher viral loads and experience more severe neurological complications than HIV-infected individuals who do not abuse drugs. The aim of this study was to determine the effect of METH on HIV expression from the HIV long terminal repeat (LTR) promoter and on an HIV integrated provirus in microglial cells, the primary host cells for HIV in the CNS. Primary human microglial cells immortalized with SV40 T antigen (CHME-5 cells) were cotransfected with an HIV LTR reporter and the HIV Tat gene, a key regulator of viral replication and gene expression, and exposed to METH. Our results demonstrate that METH treatment induced LTR activation, an effect potentiated in the presence of Tat. We also found that METH increased the nuclear translocation of the nuclear factor kappa B (NF-kappaB), a key cellular transcriptional regulator of the LTR promoter, and the activity of an NF-kappaB-specific reporter plasmid in CHME-5 cells. The presence of a dominant-negative regulator of NF-kappaB blocked METH-related activation of the HIV LTR. Furthermore, treatment of HIV-latently infected CHME-5 (CHME-5/HIV) cells with METH induced HIV expression and nuclear translocation of the p65 subunit of NF-kappaB. These results suggest that METH can stimulate HIV gene expression in microglia cells through activation of the NF-kappaB signaling pathway. This mechanism may outline the initial biochemical events leading to the observed increased neurodegeneration in HIV-positive individuals who use METH.
2011
Harvey, Brandon K; Airavaara, Mikko; Hinzman, Jason; Wires, Emily M; Chiocco, Matthew J; Howard, Douglas B; Shen, Hui; Gerhardt, Greg; Hoffer, Barry J; Wang, Yun
Targeted over-expression of glutamate transporter 1 (GLT-1) reduces ischemic brain injury in a rat model of stroke. Journal Article
In: PLoS One, vol. 6, no. 8, pp. e22135, 2011, ISSN: 1932-6203 (Electronic); 1932-6203 (Linking).
@article{Harvey2011,
title = {Targeted over-expression of glutamate transporter 1 (GLT-1) reduces ischemic brain injury in a rat model of stroke.},
author = {Brandon K Harvey and Mikko Airavaara and Jason Hinzman and Emily M Wires and Matthew J Chiocco and Douglas B Howard and Hui Shen and Greg Gerhardt and Barry J Hoffer and Yun Wang},
url = {https://www.ncbi.nlm.nih.gov/pubmed/21853027},
doi = {10.1371/journal.pone.0022135},
issn = {1932-6203 (Electronic); 1932-6203 (Linking)},
year = {2011},
date = {2011-08-09},
urldate = {2011-08-09},
journal = {PLoS One},
volume = {6},
number = {8},
pages = {e22135},
address = {Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland, United States of America. bharvey@mail.nih.gov},
abstract = {Following the onset of an ischemic brain injury, the excitatory neurotransmitter glutamate is released. The excitotoxic effects of glutamate are a major contributor to the pathogenesis of a stroke. The aim of this study was to examine if overexpression of a glutamate transporter (GLT-1) reduces ischemic brain injury in a rat model of stroke. We generated an adeno-associated viral (AAV) vector expressing the rat GLT-1 cDNA (AAV-GLT1). Functional expression of AAV-GLT1 was confirmed by increased glutamate clearance rate in non-stroke rat brain as measured by in vivo amperometry. AAV-GLT1 was injected into future cortical region of infarction 3 weeks prior to 60 min middle cerebral artery occlusion (MCAo). Tissue damage was assessed at one and two days after MCAo using TUNEL and TTC staining, respectively. Behavioral testing was performed at 2, 8 and 14 days post-stroke. Animals receiving AAV-GLT1, compared to AAV-GFP, showed significant decreases in the duration and magnitude of extracellular glutamate, measured by microdialysis, during the 60 minute MCAo. A significant reduction in brain infarction and DNA fragmentation was observed in the region of AAV-GLT1 injection. Animals that received AAV-GLT1 showed significant improvement in behavioral recovery following stroke compared to the AAV-GFP group. We demonstrate that focal overexpression of the glutamate transporter, GLT-1, significantly reduces ischemia-induced glutamate overflow, decreases cell death and improves behavioral recovery. These data further support the role of glutamate in the pathogenesis of ischemic damage in brain and demonstrate that targeted gene delivery to decrease the ischemia-induced glutamate overflow reduces the cellular and behavioral deficits caused by stroke.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Following the onset of an ischemic brain injury, the excitatory neurotransmitter glutamate is released. The excitotoxic effects of glutamate are a major contributor to the pathogenesis of a stroke. The aim of this study was to examine if overexpression of a glutamate transporter (GLT-1) reduces ischemic brain injury in a rat model of stroke. We generated an adeno-associated viral (AAV) vector expressing the rat GLT-1 cDNA (AAV-GLT1). Functional expression of AAV-GLT1 was confirmed by increased glutamate clearance rate in non-stroke rat brain as measured by in vivo amperometry. AAV-GLT1 was injected into future cortical region of infarction 3 weeks prior to 60 min middle cerebral artery occlusion (MCAo). Tissue damage was assessed at one and two days after MCAo using TUNEL and TTC staining, respectively. Behavioral testing was performed at 2, 8 and 14 days post-stroke. Animals receiving AAV-GLT1, compared to AAV-GFP, showed significant decreases in the duration and magnitude of extracellular glutamate, measured by microdialysis, during the 60 minute MCAo. A significant reduction in brain infarction and DNA fragmentation was observed in the region of AAV-GLT1 injection. Animals that received AAV-GLT1 showed significant improvement in behavioral recovery following stroke compared to the AAV-GFP group. We demonstrate that focal overexpression of the glutamate transporter, GLT-1, significantly reduces ischemia-induced glutamate overflow, decreases cell death and improves behavioral recovery. These data further support the role of glutamate in the pathogenesis of ischemic damage in brain and demonstrate that targeted gene delivery to decrease the ischemia-induced glutamate overflow reduces the cellular and behavioral deficits caused by stroke.
