Digital Commons Network^™

Chronic Muscle Weakness And Mitochondrial Dysfunction In The Absence Of Sustained Atrophy In A Preclinical Sepsis Model, Allison M. Owen, Samir P. Patel, Jeffrey D. Smith, Beverly K. Balasuriya, Stephanie F. Mori, Gregory S. Hawk, Arnold J. Stromberg, Naohide Kuriyama, Masao Kaneki, Alexander G. Rabchevsky, Timothy A. Butterfield, Karyn A. Esser, Charlotte A. Peterson, Marlene E. Starr, Hiroshi Saito

Physiology Faculty Publications

Chronic critical illness is a global clinical issue affecting millions of sepsis survivors annually. Survivors report chronic skeletal muscle weakness and development of new functional limitations that persist for years. To delineate mechanisms of sepsis-induced chronic weakness, we first surpassed a critical barrier by establishing a murine model of sepsis with ICU-like interventions that allows for the study of survivors. We show that sepsis survivors have profound weakness for at least 1 month, even after recovery of muscle mass. Abnormal mitochondrial ultrastructure, impaired respiration and electron transport chain activities, and persistent protein oxidative damage were evident in the muscle of …

The Effects Of Urbanization On Bee Communities Depends On Floral Resource Availability And Bee Functional Traits., Caleb J Wilson, Mary A Jamieson

Entomology Faculty Publications

Wild bees are important pollinators in many ecosystems threatened by anthropogenic disturbance. Urban development can reduce and degrade natural habitat for bees and other pollinators. However, some researchers suggest that cities could also provide refuge for bees, given that agricultural intensification may pose a greater risk. In this study, we surveyed bee communities at 15 farms and gardens across an urban-rural gradient in southeastern Michigan, USA to evaluate the effect of urbanization on bees. We examined how floral resources, bee functional traits, temperature, farm size, and the spatial scale of analysis influence bee response to urbanization. We found that urbanization …

Hepatobiliary Analyses Suggest Chronic Pah Exposure In Hakes (Urophycis Spp.) Following The Deepwater Horizon Oil Spill, Rachel E. Struch, Erin Pulster, Andrea D. Schreier, Steven A. Murawski

C-IMAGE Publications

Prior to the Deepwater Horizon oil spill, we lacked a comprehensive baseline of oil contamination in the Gulf of Mexico's sediments, water column, and biota. Gaps in prespill knowledge limit our ability to determine the aftereffects of the Deepwater Horizon blowout or prepare to mitigate similar impacts during future oil spill disasters. We examined spatiotemporal differences in exposure to and metabolism of polycyclic aromatic hydrocarbons (PAHs) in 2 hake species (Urophycis spp.) to establish a current baseline for these ecologically important, abundant, and at-risk demersal fishes. Gulf hake (Urophycis cirrata) and southern hake (Urophycis floridana) were collected throughout the Gulf …

Defining The Layers Of A Sensory Cilium With Storm And Cryoelectron Nanoscopy, Michael A Robichaux, Valencia L Potter, Zhixian Zhang, Feng He, Jun Liu, Michael F Schmid, Theodore G Wensel

Faculty, Staff and Students Publications

Primary cilia carry out numerous signaling and sensory functions, and defects in them, "ciliopathies," cause a range of symptoms, including blindness. Understanding of their nanometer-scale ciliary substructures and their disruptions in ciliopathies has been hindered by limitations of conventional microscopic techniques. We have combined cryoelectron tomography, enhanced by subtomogram averaging, with superresolution stochastic optical reconstruction microscopy (STORM) to define subdomains within the light-sensing rod sensory cilium of mouse retinas and reveal previously unknown substructures formed by resident proteins. Domains are demarcated by structural features such as the axoneme and its connections to the ciliary membrane, and are correlated with molecular …

Gut Microbiota: From The Forgotten Organ To A Potential Key Player In The Pathology Of Alzheimer's Disease, Dong-Oh Seo, David M Holtzman

Open Access Publications

More than 300 years ago, Antony van Leewenhoeck first described observing single-celled microorganisms, which he termed "animalcules," examining his saliva under a microscope. Although the idea of the coexistence of microorganisms in our body is not new, we have only recently been able to investigate their ecological relationship to our body, with the development of high-throughput molecular techniques. The diverse microorganism communities residing in our guts are established and maintained by complex interactions among microorganisms and their host. Notably, their alteration has been implicated in influencing various diseases including neurological diseases. Alzheimer's disease (AD) is the most common cause of …

Systemic Toxicity Reported For Cdk8/19 Inhibitors Cct251921 And Msc2530818 Is Not Due To Target Inhibition, Mengqian Chen, Jing Li, Jiaxin Liang, Zanshé S. Thompson, Katie Kathrein, Eugenia Broude, Igor Roninson

Faculty Publications

CDK8/19 kinases, which mediate transcriptional reprogramming, have become an active target for cancer drug discovery. Several small-molecule CDK8/19 inhibitors showed in vivo efficacy and two have entered clinical trials, with no significant toxicities reported. However, Clarke et al. (eLife 2016; 5; e20722) found severe systemic toxicity associated with two potent CDK8/19 inhibitors, Cmpd3 (CCT251921) and Cmpd4 (MSC2530818), and suggested that their toxicity was due to on-target effects. Here, we compared five CDK8/19 inhibitors: Cmpd3, Cmpd4, Senexin B, 16-didehydro-cortistatin A (dCA) and 15w, in different assays. Only Cmpd4 showed striking toxicity in developing zebrafish. In cell-based assays for CDK8 and CDK19 …

Dc-Script Deficiency Delays Mouse Mammary Gland Development And Branching Morphogenesis, Chunling Tang, Renske J E Van Den Bijgaart, Maaike W G Looman, Nina Tel-Karthaus, Annemarie M A De Graaf, Susan Gilfillan, Marco Colonna, Marleen Ansems, Gosse J Adema

Open Access Publications

Mammary glands are unique organs in which major adaptive changes occur in morphogenesis and development after birth. Breast cancer is the most common cancer and a major cause of mortality in females worldwide. We have previously identified the loss of expression of the transcription regulator DC-SCRIPT (Zfp366) as a prominent prognostic event in estrogen receptor positive breast cancer patients. DC-SCRIPT affects multiple transcriptional events in breast cancer cells, including estrogen and progesterone receptor-mediated transcription, and promotes CDKN2B-related cell cycle arrest. As loss of DC-SCRIPT expression appears an early event in breast cancer development, we here investigated the role of DC-SCRIPT …

Vav1 Inhibits Rankl-Induced Osteoclast Differentiation And Bone Resorption., Jin Sun Jang, In Soon Kang, Young-Nam Cha, Zang Hee Lee, Mary C Dinauer, Young-June Kim, Chaekyun Kim

Open Access Publications

Vav1 is a Rho/Rac guanine nucleotide exchange factor primarily expressed in hematopoietic cells. In this study, we investigated the potential role of Vav1 in osteoclast (OC) differentiation by comparing the ability of bone marrow mononuclear cells (BMMCs) obtained from Vav1-deficient (Vav1-/-) and wild-type (WT) mice to differentiate into mature OCs upon stimulation with macrophage colony stimulating factor and receptor activator of nuclear kappa B ligand in vitro. Our results suggested that Vav1 deficiency promoted the differentiation of BMMCs into OCs, as indicated by the increased expression of tartrate-resistant acid phosphatase, cathepsin K, and calcitonin receptor. Therefore, Vav1 may play a …

Sirna Targeting And Treatment Of Gastrointestinal Diseases., Rachel Chevalier

Manuscripts, Articles, Book Chapters and Other Papers

RNA interference via small interfering RNA (siRNA) offers opportunities to precisely target genes that contribute to gastrointestinal (GI) pathologies, such as inflammatory bowel disease, celiac, and esophageal scarring. Delivering the siRNA to the GI tract proves challenging as the harsh environment of the intestines degrades the siRNA before it can reach its target or blocks its entry into its site of action in the cytoplasm. Additionally, the GI tract is large and disease is often localized to a specific site. This review discusses polymer and lipid-based delivery systems for protection and targeting of siRNA therapies to the GI tract to …

Cis-Regulatory Basis Of Sister Cell Type Divergence In The Vertebrate Retina, Daniel P Murphy, Andrew Eo Hughes, Karen A Lawrence, Connie A Myers, Joseph C Corbo

2010-2019 OA Pubs

Multicellular organisms evolved via repeated functional divergence of transcriptionally related sister cell types, but the mechanisms underlying sister cell type divergence are not well understood. Here, we study a canonical pair of sister cell types, retinal photoreceptors and bipolar cells, to identify the key

Stimulation Of Piezo1 By Mechanical Signals Promotes Bone Anabolism, Xuehua Li, Li Han, Intawat Nookaew, Erin Mannen, Matthew J. Silva, Maria Almeida, Jinhu Xiong

Open Access Publications

Mechanical loading, such as caused by exercise, stimulates bone formation by osteoblasts and increases bone strength, but the mechanisms are poorly understood. Osteocytes reside in bone matrix, sense changes in mechanical load, and produce signals that alter bone formation by osteoblasts. We report that the ion channel Piezo1 is required for changes in gene expression induced by fluid shear stress in cultured osteocytes and stimulation of Piezo1 by a small molecule agonist is sufficient to replicate the effects of fluid flow on osteocytes. Conditional deletion of

Irak4 Mediates Colitis-Induced Tumorigenesis And Chemoresistance In Colorectal Cancer, Qiong Li, Yali Chen, Daoxiang Zhang, Julie Grossman, Lin Li, Namrata Khurana, Hongmei Jiang, Patrick M Grierson, John Herndon, David G Denardo, Grant A Challen, Jingxia Liu, Marianna B Ruzinova, Ryan C Fields, Kian-Huat Lim

Open Access Publications

Aberrant activation of the NF-κB transcription factors underlies chemoresistance in various cancer types, including colorectal cancer (CRC). Targeting the activating mechanisms, particularly with inhibitors to the upstream IκB kinase (IKK) complex, is a promising strategy to augment the effect of chemotherapy. However, clinical success has been limited, largely because of low specificity and toxicities of tested compounds. In solid cancers, the IKKs are driven predominantly by the Toll-like receptor (TLR)/IL-1 receptor family members, which signal through the IL-1 receptor-associated kinases (IRAKs), with isoform 4 (IRAK4) being the most critical. The pathogenic role and therapeutic value of IRAK4 in CRC have …

Sr9009 Administered For One Day After Myocardial Ischemia-Reperfusion Prevents Heart Failure In Mice By Targeting The Cardiac Inflammasome, Cristine J Reitz, Faisal J Alibhai, Tarak N Khatua, Mina Rasouli, Byram W Bridle, Thomas P Burris, Tami A Martino

Open Access Publications

Reperfusion of patients after myocardial infarction (heart attack) triggers cardiac inflammation that leads to infarct expansion and heart failure (HF). We previously showed that the circadian mechanism is a critical regulator of reperfusion injury. However, whether pharmacological targeting using circadian medicine limits reperfusion injury and protects against HF is unknown. Here, we show that short-term targeting of the circadian driver REV-ERB with SR9009 benefits long-term cardiac repair post-myocardial ischemia reperfusion in mice. Gain and loss of function studies demonstrate specificity of targeting REV-ERB in mice. Treatment for just one day abates the cardiac NLRP3 inflammasome, decreasing immunocyte recruitment, and thereby …

Keep The Cat, Change The Care Pathway: A Transformational Approach To Managing Fel D 1, The Major Cat Allergen, Ebenezer Satyaraj, Harold James Wedner, Jean Bousquet

2010-2019 OA Pubs

BACKGROUND: Allergies to cats are the most common animal-origin allergy, and affect approximately 1 in 5 adults worldwide. The prevalence of allergy to furry animals has been increasing, and allergy to cats is a major risk factor for the development of asthma and rhinitis. The diagnosis of cat allergy is now well established. The exact significance of component-resolved diagnosis in the diagnosis of cat allergy remains to be fully understood. Allergen avoidance is effective but often has a psychologic impact. Allergen immunotherapy is not well demonstrated. There is a need for innovative approaches to better manage cat allergens. Next-generation care …

Stub1 Suppresseses Tumorigenesis And Chemoresistance Through Antagonizing Yap1 Signaling, Dong-E Tang, Yong Dai, Lie-Wen Lin, Yong Xu, Dong-Zhou Liu, Xiao-Ping Hong, Hao-Wu Jiang, Song-Hui Xu

Open Access Publications

Yes-associated protein (YAP) is a component of the canonical Hippo signaling pathway that is known to play essential roles in modulating organ size, development, and tumorigenesis. Activation or upregulation of YAP1, which contributes to cancer cell survival and chemoresistance, has been verified in different types of human cancers. However, the molecular mechanism of YAP1 upregulation in cancer is still unclear. Here we report that the E3 ubiquitin ligase STUB1 ubiquitinates and destabilizes YAP1, thereby inhibiting cancer cell survival. Low levels of STUB1 expression were correlated with increased protein levels of YAP1 in human gastric cancer cell lines and patient samples. …

Astrovirus Replication In Human Intestinal Enteroids Reveals Multi-Cellular Tropism And An Intricate Host Innate Immune Landscape, Abimbola O. Kolawole, Andrew B Janowski, David Wang, Christiane E. Wobus, Et Al.

Open Access Publications

Human astroviruses (HAstV) are understudied positive-strand RNA viruses that cause gastroenteritis mostly in children and the elderly. Three clades of astroviruses, classic, MLB-type and VA-type have been reported in humans. One limitation towards a better understanding of these viruses has been the lack of a physiologically relevant cell culture model that supports growth of all clades of HAstV. Herein, we demonstrate infection of HAstV strains belonging to all three clades in epithelium-only human intestinal enteroids (HIE) isolated from biopsy-derived intestinal crypts. A detailed investigation of infection of VA1, a member of the non-canonical HAstV-VA/HMO clade, showed robust replication in HIE …

A Human Stat1 Gain-Of-Function Mutation Impairs Cd8 + T Cell Responses Against Gammaherpesvirus 68, Wei Qian, Cathrine A Miner, Harshad Ingle, Derek J Platt, Megan T Baldridge, Jonathan J Miner

Open Access Publications

Autosomal dominant STAT1 mutations in humans have been associated with chronic mucocutaneous candidiasis (CMC), as well as with increased susceptibility to herpesvirus infections. Prior studies have focused on mucosal and Th17-mediated immunity against

Fgf-Signaling Is Compartmentalized Within The Mesenchyme And Controls Proliferation During Salamander Limb Development, Sruthi Purushothaman, Ahmed Elewa, Ashley W. Seifert

Biology Faculty Publications

Although decades of studies have produced a generalized model for tetrapod limb development, urodeles deviate from anurans and amniotes in at least two key respects: their limbs exhibit preaxial skeletal differentiation and do not develop an apical ectodermal ridge (AER). Here, we investigated how Sonic hedgehog (Shh) and Fibroblast growth factor (Fgf) signaling regulate limb development in the axolotl. We found that Shh-expressing cells contributed to the most posterior digit, and that inhibiting Shh-signaling inhibited Fgf8 expression, anteroposterior patterning, and distal cell proliferation. In addition to lack of a morphological AER, we found that salamander …

Inhibition Of 4-Aminobutyrate Aminotransferase Protects Against Injury-Induced Osteoarthritis In Mice, Jie Shen, Cuicui Wang, Jun Ying, Taotao Xu, Audrey Mcalinden, Regis J. O'Keefe

Open Access Publications

Recently we demonstrated that ablation of the DNA methyltransferase enzyme, Dnmt3b, resulted in catabolism and progression of osteoarthritis (OA) in murine articular cartilage through a mechanism involving increased mitochondrial respiration. In this study, we identify 4-aminobutyrate aminotransferase (Abat) as a downstream target of Dnmt3b. Abat is an enzyme that metabolizes γ-aminobutyric acid to succinate, a key intermediate in the tricarboxylic acid cycle. We show that Dnmt3b binds to the Abat promoter, increases methylation of a conserved CpG sequence just upstream of the transcriptional start site, and inhibits Abat expression. Dnmt3b deletion in articular chondrocytes results in reduced methylation of the …

Multispectral Tracing In Densely Labeled Mouse Brain With Ntracer, Douglas H Roossien, John M Webb, Cristina Mazuski, Erik D Herzog, Et Al.

2010-2019 OA Pubs

SUMMARY: This note describes nTracer, an ImageJ plug-in for user-guided, semi-automated tracing of multispectral fluorescent tissue samples. This approach allows for rapid and accurate reconstruction of whole cell morphology of large neuronal populations in densely labeled brains.

AVAILABILITY AND IMPLEMENTATION: nTracer was written as a plug-in for the open source image processing software ImageJ. The software, instructional documentation, tutorial videos, sample image and sample tracing results are available at https://www.cai-lab.org/ntracer-tutorial.

SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Imatinib Mesylate Effects On Zebrafish Reproductive Success: Gonadal Development, Gamete Quality, Fertility, Embryo-Larvae Viability And Development, And Related Genes, Nader Ahmadi, Seyed-Mohammadreza Samaee, Robert A. Yokel, Aliasghar Tehrani

Pharmaceutical Sciences Faculty Publications

Imatinib (IM) is a tyrosine kinase (TK) inhibitor (TKI) used to treat chronic myeloid leukemia. Clinical case reports and a few laboratory mammal studies provide inconclusive evidence about its deleterious effects on reproduction. The aim of the current study was to evaluate the potential of zebrafish to characterize IM-induced effects on reproduction and clarify IM effects on reproductive success. To this end, we exposed adult zebrafish to four concentrations of IM for 30 days followed by a 30-day depuration period. IM exposure caused a concentration-dependent, irreversible, suppression of folliculogenesis, reversible decrease in sperm density and motility, decreased fecundity and fertility, …

Virus-Induced Cochlear Inflammation In Newborn Mice Alters Auditory Function, Cathy Yea Won Sung, Maria C. Seleme, Shelby Payne, Stipan Jonjic, Keiko Hirose, William Britt

Open Access Publications

Although human cytomegalovirus (HCMV) is a known cause of sensorineural hearing loss in infants with congenital HCMV (cCMV) infections, mechanisms that contribute to sensorineural hearing loss (SNHL) in infants with cCMV infection are not well defined. Using a murine model of CMV infection during auditory development, we have shown that peripheral infection of newborn mice with murine CMV (MCMV) results in focal infection of the cochlea and virus-induced cochlear inflammation. Approximately 50%-60% of infected mice exhibited increased auditory brainstem response (ABR) thresholds across a range of sound frequencies. Histological analyses of the cochlea in MCMV-infected mice with elevated ABR thresholds …

Altered Gating Of KV1.4 In The Nucleus Accumbens Suppresses Motivation For Reward, Bernadette O'Donovan, Adewale Adeluyi, Erin L Anderson, Robert D. Cole, Jill R. Turner, Pavel I. Ortinski

Neuroscience Faculty Publications

Deficient motivation contributes to numerous psychiatric disorders, including withdrawal from drug use, depression, schizophrenia, and others. Nucleus accumbens (NAc) has been implicated in motivated behavior, but it remains unclear whether motivational drive is linked to discrete neurobiological mechanisms within the NAc. To examine this, we profiled cohorts of Sprague-Dawley rats in a test of motivation to consume sucrose. We found that substantial variability in willingness to exert effort for reward was not associated with operant responding under low-effort conditions or stress levels. Instead, effort-based motivation was mirrored by a divergent NAc shell transcriptome with differential regulation at potassium and dopamine …

Vincristine And Bortezomib Use Distinct Upstream Mechanisms To Activate A Common Sarm1-Dependent Axon Degeneration Program, Stefanie Geisler, Ryan A Doan, Galen C Cheng, Aysel Cetinkaya-Fisgin, Shay X Huang, Ahmet Höke, Jeffrey Milbrandt, Aaron Diantonio

Open Access Publications

Chemotherapy-induced peripheral neuropathy is one of the most prevalent dose-limiting toxicities of anticancer therapy. Development of effective therapies to prevent chemotherapy-induced neuropathies could be enabled by a mechanistic understanding of axonal breakdown following exposure to neuropathy-causing agents. Here, we reveal the molecular mechanisms underlying axon degeneration induced by 2 widely used chemotherapeutic agents with distinct mechanisms of action: vincristine and bortezomib. We showed previously that genetic deletion of SARM1 blocks vincristine-induced neuropathy and demonstrate here that it also prevents axon destruction following administration of bortezomib in vitro and in vivo. Using cultured neurons, we found that vincristine and bortezomib converge …

Unraveling The Functional Role Of The Orphan Solute Carrier, Slc22a24 In The Transport Of Steroid Conjugates Through Metabolomic And Genome-Wide Association Studies, Sook Wah Yee, Adrian Stecula, Huan-Chieh Chien, Ling Zou, Elena V Feofanova, Marjolein Van Borselen, Kit Wun Kathy Cheung, Noha A Yousri, Karsten Suhre, Jason M Kinchen, Eric Boerwinkle, Roshanak Irannejad, Bing Yu, Kathleen M Giacomini

Faculty, Staff and Student Publications

Variation in steroid hormone levels has wide implications for health and disease. The genes encoding the proteins involved in steroid disposition represent key determinants of interindividual variation in steroid levels and ultimately, their effects. Beginning with metabolomic data from genome-wide association studies (GWAS), we observed that genetic variants in the orphan transporter, SLC22A24 were significantly associated with levels of androsterone glucuronide and etiocholanolone glucuronide (sentinel SNPs p-value

Dhx33 Interacts With Ap-2Β To Regulate Bcl-2 Gene Expression And Promote Cancer Cell Survival, Jiuling Wang, Weimin Feng, Zhen Yuan, Jason D. Weber, Yandong Zhang

Open Access Publications

The RNA helicase DHX33 has been found to be overexpressed in human cancers, where it promotes cancer development. Previous reports have shown that DHX33 deficiency caused cancer cell apoptosis, but the underlying mechanism remains unknown. In this study, we discovered that DHX33 regulates Bcl-2 family protein expression. In multiple human cancer cell lines, DHX33 was found to stimulate the transcription of

Omnipresence Of Inflammasome Activities In Inflammatory Bone Diseases, Yael Alippe, Gabriel Mbalaviele

Open Access Publications

The inflammasomes are intracellular protein complexes that are assembled in response to a variety of perturbations including infections and injuries. Failure of the inflammasomes to rapidly clear the insults or restore tissue homeostasis can result in chronic inflammation. Recurring inflammation is also provoked by mutations that cause the constitutive assembly of the components of these protein platforms. Evidence suggests that chronic inflammation is a shared mechanism in bone loss associated with aging, dysregulated metabolism, autoinflammatory, and autoimmune diseases. Mechanistically, inflammatory mediators promote bone resorption while suppressing bone formation, an imbalance which over time leads to bone loss and increased fracture …

Four-Jointed Knock-Out Delays Renal Failure In An Adpkd Model With Kidney Injury, Chiara Formica, Hester Happé, Kimberley Am Veraar, Andrea Vortkamp, Marion Scharpfenecker, Helen Mcneill, Dorien Jm Peters

Open Access Publications

Autosomal Dominant Polycystic Kidney Disease is characterised by the development of fluid-filled cysts in the kidneys which lead to end-stage renal disease (ESRD). In the majority of cases, the disease is caused by a mutation in the Pkd1 gene. In a previous study, we demonstrated that renal injury can accelerate cyst formation in Pkd1 knock-out (KO) mice. In that study, we found that after injury four-jointed (Fjx1), an upstream regulator of planar cell polarity and the Hippo pathway, was aberrantly expressed in Pkd1 KO mice compared to WT. Therefore, we hypothesised a role for Fjx1 in injury/repair and cyst formation. …

Nuclear Receptor Subfamily 4 Group A Member 2 Inhibits Activation Of Erk Signaling And Cell Growth In Response To Β-Adrenergic Stimulation In Adult Rat Cardiomyocytes, Sadia Ashraf, Yassmin K Hegazy, Romain Harmancey

Faculty, Staff and Student Publications

Sustained elevation of sympathetic activity is an important contributor to pathological cardiac hypertrophy, ventricular arrhythmias, and left ventricular contractile dysfunction in chronic heart failure. The orphan nuclear receptor NR4A2 is an immediate early-response gene activated in the heart under β-adrenergic stimulation. The goal of this study was to identify the transcriptional remodeling events induced by increased NR4A2 expression in cardiomyocytes and their impact on the physiological response of those cells to sustained β-adrenergic stimulation. Treatment of adult rat ventricular myocytes with isoproterenol induced a rapid (<4 >h) increase in NR4A2 levels that was accompanied by a transient (<24 >h) increase …

Nuclear Receptor Subfamily 4 Group A Member 2 Inhibits Activation Of Erk Signaling And Cell Growth In Response To Β-Adrenergic Stimulation In Adult Rat Cardiomyocytes, Sadia Ashraf, Yassmin K Hegazy, Romain Harmancey

Faculty, Staff and Student Publications

Sustained elevation of sympathetic activity is an important contributor to pathological cardiac hypertrophy, ventricular arrhythmias, and left ventricular contractile dysfunction in chronic heart failure. The orphan nuclear receptor NR4A2 is an immediate early-response gene activated in the heart under β-adrenergic stimulation. The goal of this study was to identify the transcriptional remodeling events induced by increased NR4A2 expression in cardiomyocytes and their impact on the physiological response of those cells to sustained β-adrenergic stimulation. Treatment of adult rat ventricular myocytes with isoproterenol induced a rapid (<4 >h) increase in NR4A2 levels that was accompanied by a transient (<24 >h) increase …