Activation of BDNF by transcription factor Nrf2 contributes to antidepressant-like actions in rodents

AbstractThe transcription factor erythroid 2-related factor 2 (Nrf2) and brain-derived neurotrophic factor (BDNF) play a key role in depression. However, the molecular mechanisms underlying the crosstalk between Nrf2 and BDNF in depression remain unclear. We examined whether Nrf2 regulates the transcription of Bdnf by binding to its exon I promoter. Furthermore, the role of Nrf2 and BDNF in the brain regions from mice with depression-like phenotypes was examined. Nrf2 regulated the transcription of Bdnf by binding to its exon I promoter. Activation of Nrf2 by sulforaphane (SFN) showed fast-acting antidepressant-like effects in mice by activating BDNF as well as by inhibiting the expression of its transcriptional repressors (HDAC2, mSin3A, and MeCP2) and revising abnormal synaptic transmission. In contrast, SFN did not affect the protein expression of BDNF and its transcriptional repressor proteins in the medial prefrontal cortex (mPFC) and hippocampus, nor did it reduce depression-like behaviors and abnormal synaptic transmission in Nrf2 knockout mice. In the mouse model of chronic social defeat stress (CSDS), protein levels of Nrf2 and BDNF in the mPFC and hippocampus were lower than those of control and CSDS-resilient mice. In contrast, the protein levels of BDNF transcriptional repressors in the CSDS-susceptible mice were higher than those of control and CSDS-resilient mice. These data suggest that Nrf2 activation increases the expression of Bdnf and decreases the expression of its transcriptional repressors, which result in fast-acting antidepressant-like actions. Furthermore, abnormalities in crosstalk between Nrf2 and BDNF may contribute to the resilience versus susceptibility of mice against CSDS.

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Acquired Glucocorticoid Resistance Due to Homologous Glucocorticoid Receptor Downregulation: A Modern Look at an Age-Old Problem

Cells ◽

10.3390/cells10102529 ◽

2021 ◽

Vol 10 (10) ◽

pp. 2529

Author(s):

Lee-Maine L. Spies ◽

Nicolette J. D. Verhoog ◽

Ann Louw

Keyword(s):

Transcription Factor ◽

Side Effects ◽

Pharmaceutical Industry ◽

Glucocorticoid Receptor ◽

Steroid Hormones ◽

Molecular Mechanisms ◽

Protein Levels ◽

Current Review ◽

Role Players ◽

Receptor Conformation

For over 70 years, the unique anti-inflammatory properties of glucocorticoids (GCs), which mediate their effects via the ligand-activated transcription factor, the glucocorticoid receptor alpha (GRα), have allowed for the use of these steroid hormones in the treatment of various autoimmune and inflammatory-linked diseases. However, aside from the onset of severe side-effects, chronic GC therapy often leads to the ligand-mediated downregulation of the GRα which, in turn, leads to a decrease in GC sensitivity, and effectively, the development of acquired GC resistance. Although the ligand-mediated downregulation of GRα is well documented, the precise factors which influence this process are not well understood and, thus, the development of an acquired GC resistance presents an ever-increasing challenge to the pharmaceutical industry. Recently, however, studies have correlated the dimerization status of the GRα with its ligand-mediated downregulation. Therefore, the current review will be discussing the major role-players in the homologous downregulation of the GRα pool, with a specific focus on previously reported GC-mediated reductions in GRα mRNA and protein levels, the molecular mechanisms through which the GRα functional pool is maintained and the possible impact of receptor conformation on GC-mediated GRα downregulation.

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Dual regulation of transcription factor Nrf2 by Keap1 and by the combined actions of β-TrCP and GSK-3

Biochemical Society Transactions ◽

10.1042/bst20150011 ◽

2015 ◽

Vol 43 (4) ◽

pp. 611-620 ◽

Cited By ~ 59

Author(s):

John D. Hayes ◽

Sudhir Chowdhry ◽

Albena T. Dinkova-Kostova ◽

Calum Sutherland

Keyword(s):

Transcription Factor ◽

Growth Factors ◽

Ubiquitin Ligase ◽

Molecular Mechanisms ◽

Glycogen Synthase ◽

Proteasomal Degradation ◽

Regulation Of Transcription ◽

Related Factor ◽

Nrf2 Target Gene ◽

The Stability

Nuclear factor-erythroid 2 p45 (NF-E2 p45)-related factor 2 (Nrf2) is a master regulator of redox homoeostasis that allows cells to adapt to oxidative stress and also promotes cell proliferation. In this review, we describe the molecular mechanisms by which oxidants/electrophilic agents and growth factors increase Nrf2 activity. In the former case, oxidants/electrophiles increase the stability of Nrf2 by antagonizing the ability of Kelch-like ECH-associated protein 1 (Keap1) to target the transcription factor for proteasomal degradation via the cullin-3 (Cul3)–RING ubiquitin ligase CRLKeap1. In the latter case, we speculate that growth factors increase the stability of Nrf2 by stimulating phosphoinositide 3-kinase (PI3K)−protein kinase B (PKB)/Akt signalling, which in turn results in inhibitory phosphorylation of glycogen synthase kinase-3 (GSK-3) and in doing so prevents the formation of a DSGIS motif-containing phosphodegron in Nrf2 that is recognized by the β-transducin repeat-containing protein (β-TrCP) Cul1-based E3 ubiquitin ligase complex SCFβ-TrCP. We present data showing that in the absence of Keap1, the electrophile tert-butyl hydroquinone (tBHQ) can stimulate Nrf2 activity and induce the Nrf2-target gene NAD(P)H:quinone oxidoreductase-1 (NQO1), whilst simultaneously causing inhibitory phosphorylation of GSK-3β at Ser9. Together, these observations suggest that tBHQ can suppress the ability of SCFβ-TrCP to target Nrf2 for proteasomal degradation by increasing PI3K−PKB/Akt signalling. We also propose a scheme that explains how other protein kinases that inhibit GSK-3 could stimulate induction of Nrf2-target genes by preventing formation of the DSGIS motif-containing phosphodegron in Nrf2.

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Oregano Essential Oil Induces SOD1 and GSH Expression through Nrf2 Activation and Alleviates Hydrogen Peroxide-Induced Oxidative Damage in IPEC-J2 Cells

Oxidative Medicine and Cellular Longevity ◽

10.1155/2016/5987183 ◽

2016 ◽

Vol 2016 ◽

pp. 1-13 ◽

Cited By ~ 22

Author(s):

Yi Zou ◽

Jun Wang ◽

Jian Peng ◽

Hongkui Wei

Keyword(s):

Hydrogen Peroxide ◽

Essential Oil ◽

Molecular Mechanisms ◽

Target Genes ◽

Cell Damage ◽

Antioxidant Response ◽

Related Factor ◽

Protective Effects ◽

Oregano Essential Oil ◽

Protein Levels

Oregano essential oil (OEO) has long been used to improve the health of animals, particularly their intestinal health. The health benefits of OEO are generally attributed to antioxidative actions, but the mechanisms remain unclear. Here, we investigate the antioxidative effects of OEO and their underlying molecular mechanisms in porcine small intestinal epithelial (IPEC-J2) cells. We found that OEO treatment prior to hydrogen peroxide (H2O2) exposure increased cell viability and prevented lactate dehydrogenase (LDH) release into the medium. H2O2-induced reactive oxygen species (ROS) and malondialdehyde (MDA) were remarkably suppressed by OEO. OEO dose-dependently increased mRNA and protein levels of the nuclear factor-erythroid 2-related factor-2 (Nrf2) target genes Cu/Zn-superoxide dismutase (SOD1) and g-glutamylcysteine ligase (GCLC, GLCM), as well as intracellular concentrations of SOD1 and glutathione. OEO also increased intranuclear expression of Nrf2 and the activity of an antioxidant response element reporter plasmid in IPEC-J2 cells. The OEO-induced expression of Nrf2-regulated genes and increased SOD1 and glutathione concentrations in IPEC-J2 cells were reduced by Nrf2 small interfering (si) RNAs, counteracting the protective effects of OEO against oxidative stress in IPEC-J2 cells. Our results suggest that OEO protects against H2O2-induced IPEC-J2 cell damage by inducing Nrf2 and related antioxidant enzymes.

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Longitudinal noninvasive monitoring of transcription factor activation in cardiovascular regulatory nuclei using bioluminescence imaging

Physiological Genomics ◽

10.1152/physiolgenomics.00296.2007 ◽

2008 ◽

Vol 33 (2) ◽

pp. 292-299 ◽

Cited By ~ 10

Author(s):

Jeffrey R. Peterson ◽

David W. Infanger ◽

Valdir A. Braga ◽

Yulong Zhang ◽

Ram V. Sharma ◽

...

Keyword(s):

Transcription Factor ◽

Gene Transfer ◽

Molecular Mechanisms ◽

Bioluminescence Imaging ◽

Brain Regions ◽

Luciferase Reporter ◽

Viral Gene ◽

Adenoviral Delivery ◽

Wide Range

The ability to monitor transcription factor (TF) activation in the central nervous system (CNS) has the potential to provide novel information regarding the molecular mechanisms underlying a wide range of neurobiological processes. However, traditional biochemical assays limit the mapping of TF activity to select time points. In vivo bioluminescence imaging (BLI) has emerged as an attractive technology for visualizing internal molecular events in the same animal over time. Here, we evaluated the utility of BLI, in combination with virally mediated delivery of reporter constructs to cardiovascular nuclei, for monitoring of TF activity in these discrete brain regions. Following viral gene transfer of NF-κB-driven luciferase reporter to the subfornical organ (SFO), BLI enabled daily measurements of baseline TF activity in the same animal for 1 mo. Importantly, systemic endotoxin, a stimulator of NF-κB activity, induced dramatic and dose-dependent increases in NF-κB-dependent bioluminescence in the SFO up to 30 days after gene transfer. Cotreatment with a dominant-negative IκBα mutant significantly prevented endotoxin-dependent NF-κB activation, confirming the specificity of the bioluminescence signal. NF-κB-dependent luminescence signals were also stable and inducible 1 mo following delivery of luciferase reporter construct to the paraventricular nucleus or rostral ventrolateral medulla. Lastly, using targeted adenoviral delivery of an AP-1 responsive luciferase reporter, we showed similar baseline and endotoxin-induced AP-1 activity in these same brain regions as with NF-κB reporters. These results demonstrate that BLI, in combination with virally mediated gene transfer, is a powerful method for longitudinal monitoring and quantification of TF activity in targeted CNS nuclei in vivo.

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The Inhibitor of NF-KB Kinase, IKKβ Regulates the Transcriptional Activity of GLI1 By Blocking Its Proteasomal Degradation

Blood ◽

10.1182/blood.v124.21.2199.2199 ◽

2014 ◽

Vol 124 (21) ◽

pp. 2199-2199

Author(s):

Nitin Kumar Agarwal ◽

Chae Hwa Kim ◽

Kranthi Kunkalla ◽

Izidore S. Lossos ◽

Francisco Vega

Keyword(s):

Mass Spectrometry ◽

Transcription Factor ◽

Transcriptional Activity ◽

Molecular Mechanisms ◽

Ion Trap ◽

Conflicts Of Interest ◽

Tumor Development ◽

B Cell Lymphoma ◽

Protein Levels ◽

Data Links

Abstract GLI1 is a Hedgehog (Hh) related transcription factor originally discovered as an amplified product in gliomas. Inappropriate activation of the GLI1 has been shown in many cancers including diffuse large B cell lymphoma (DLBCL). We previously showed that GLI1 mediated canonical Hh signaling is constitutive active in DLBCL and contributes to cell survival, proliferation and enhances chemotolerance. Although the importance of GLI1 in tumor development is well recognized, the molecular mechanisms controlling the transcriptional activity of GLI1 are poorly characterized. To identify regulatory components that participate in the transcriptional activity of GLI1, we explored GLI1 putative interacting proteins by liquid chromatography tandem mass spectrometry following immunoprecipitation of endogenous GLI1. We detected that the inhibitor of NF-KB kinase, IKKβ, is one of the proteins associated with GLI1 transcription factor. Here we investigate the regulatory role of IKKβ in the transcriptional activity of GLI1. We show that IKKβ regulates the transcriptional activity of GLI1 by phosphorylating GLI1 in C-terminal region and modulating its protein stability. Short stimulation of SUDHL4 and DOHH2 cells with TNF-α (20ng/mL) resulted in increased GLI1 protein levels. Similar results were observed in 293T cells transiently transfected with GLI1 and IKKβ kinase constructs. Moreover, silencing of IKKβ using siRNA and shRNAs led to decreased GLI1 protein levels and its transcriptional activity in DLBCL cell lines with constitutive activation of the NF-KB. Next, we characterized nine probable IKKβ dependent GLI1 phosphorylation sites (S543-S548, S1070, S1071 and S1074 identified by nanospray ion trap mass spectrometry) using mutational and deletions studies. We show that IKKβ phosphorylates GLI1 at Thr1074 and decreases binding between GLI1 and HECT-type E3 ubiquitin ligase (ITCH) resulting in reduced GLI1 polyubiquitination and degradation. Point mutation of Threonine 1074 to Alanine prevents IKKβ-mediated GLI1 phosphorylation and facilitates GLI1-ITCH interaction, polyubiquitination and degradation of GLI1 in the proteasome. Collectively, our data links IKKβ-mediated NF-kB signaling to the transcriptional activity of GLI1 and illustrates a novel cross talk between these two pathways. This is of clinical interest because activation of the NF-kB pathway is frequent in DLBCL and the connection between Hh and NF-kB pathways may open novel therapeutic avenues for DLBCL. Disclosures No relevant conflicts of interest to declare.

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Gain-of-function genetic screen of the kinome reveals BRSK2 as an inhibitor of the NRF2 transcription factor

Journal of Cell Science ◽

10.1242/jcs.241356 ◽

2020 ◽

Vol 133 (14) ◽

pp. jcs241356 ◽

Cited By ~ 5

Author(s):

Tigist Y. Tamir ◽

Brittany M. Bowman ◽

Megan J. Agajanian ◽

Dennis Goldfarb ◽

Travis P. Schrank ◽

...

Keyword(s):

Transcription Factor ◽

Protein Kinase ◽

Human Cancer ◽

Antioxidant Response ◽

Genetic Screen ◽

Related Factor ◽

Dependent Manner ◽

Gain Of Function ◽

Protein Levels ◽

Nrf2 Protein

ABSTRACTNuclear factor erythroid 2-related factor 2 (NFE2L2, also known as NRF2) is a transcription factor and master regulator of cellular antioxidant response. Aberrantly high NRF2-dependent transcription is recurrent in human cancer, but conversely NRF2 activity diminishes with age and in neurodegenerative and metabolic disorders. Although NRF2-activating drugs are clinically beneficial, NRF2 inhibitors do not yet exist. Here, we describe use of a gain-of-function genetic screen of the kinome to identify new druggable regulators of NRF2 signaling. We found that the under-studied protein kinase brain-specific kinase 2 (BRSK2) and the related BRSK1 kinases suppress NRF2-dependent transcription and NRF2 protein levels in an activity-dependent manner. Integrated phosphoproteomics and RNAseq studies revealed that BRSK2 drives 5′-AMP-activated protein kinase α2 (AMPK) signaling and suppresses the mTOR pathway. As a result, BRSK2 kinase activation suppresses ribosome-RNA complexes, global protein synthesis and NRF2 protein levels. Collectively, our data illuminate the BRSK2 and BRSK1 kinases, in part by functionally connecting them to NRF2 signaling and mTOR. This signaling axis might prove useful for therapeutically targeting NRF2 in human disease.This article has an associated First Person interview with the first author of the paper.

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Hlx homeobox transcription factor negatively regulates interferon-γ production in monokine-activated natural killer cells

Blood ◽

10.1182/blood-2006-10-050096 ◽

2006 ◽

Vol 109 (6) ◽

pp. 2481-2487 ◽

Cited By ~ 16

Author(s):

Brian Becknell ◽

Tiffany L. Hughes ◽

Aharon G. Freud ◽

Bradley W. Blaser ◽

Jianhua Yu ◽

...

Keyword(s):

Transcription Factor ◽

Nk Cells ◽

Natural Killer ◽

Molecular Mechanisms ◽

Interferon Γ ◽

Tumor Surveillance ◽

Protein Levels ◽

Homeobox Transcription Factor ◽

Ifn Γ

Abstract Natural killer (NK) cells contribute to host immunity, including tumor surveillance, through the production of interferon gamma (IFN-γ). Although there is some knowledge about molecular mechanisms that induce IFN-γ in NK cells, considerably less is known about the mechanisms that reduce its expression. Here, we investigate the role of the Hlx transcription factor in IFN-γ production by NK cells. Hlx expression is induced in monokine-activated NK cells, but with delayed kinetics compared to IFN-γ. Ectopic Hlx expression decreases IFN-γ synthesis in primary human NK cells and IFN-γ promoter activity in an NK-like cell line. Hlx protein levels inversely correlate with those of STAT4, a requisite factor for optimal IFN-γ transcription. Mechanistically, we provide evidence indicating that Hlx overexpression accelerates dephosphorylation and proteasome-dependent degradation of the active Y693-phosphorylated form of STAT4. Thus, Hlx expression in activated NK cells temporally controls and limits the monokine-induced production of IFN-γ, in part through the targeted depletion of STAT4.

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The activity-dependent transcription factor Npas4 regulates IQSEC3 expression in somatostatin interneurons to mediate anxiety-like behavior

10.1101/659805 ◽

2019 ◽

Author(s):

Seungjoon Kim ◽

Dongseok Park ◽

Jinhu Kim ◽

Dongsoo Lee ◽

Dongwook Kim ◽

...

Keyword(s):

Transcription Factor ◽

Synaptic Transmission ◽

Molecular Mechanisms ◽

Dominant Negative ◽

Normal Brain ◽

Gabaergic Synapse ◽

Iq Motif ◽

Brain Functions ◽

Activity Dependent ◽

Gabaergic Synaptic Transmission

AbstractOrganization of mammalian inhibitory synapses is thought to be crucial for normal brain functions, but the underlying molecular mechanisms have been still incompletely understood. IQSEC3 (IQ motif and Sec7 domain 3) is a guanine nucleotide exchange factor for ADP-ribosylation factor (ARF-GEF) that directly interacts with gephyrin. Here, we show that GABAergic synapse-specific transcription factor, Npas4 (neuronal PAS domain protein 4) directly binds to the promoter of Iqsec3 and regulates its transcription. Strikingly, an enriched environment (EE) induced Npas4 upregulation and concurrently increased IQSEC3 protein levels specifically in mouse CA1 stratum oriens layer somatostatin (SST)-expressing GABAergic interneurons, which are compromised in Npas4-knockout (KO) mice. Moreover, expression of wild-type (WT) IQSEC3, but not a dominant-negative (DN) ARF-GEF–inactive mutant, rescued the decreased GABAergic synaptic transmission in Npas4-deficient SST interneurons. Concurrently, expression of IQSEC3 WT normalized the altered GABAergic synaptic transmission in dendrites, but not soma, of Npas4-deficient CA1 pyramidal neurons. Furthermore, expression of IQSEC3 WT, but not IQSEC3 DN, in SST-expressing interneurons in CA1 SST Npas4-KO mice rescued the altered anxiety-like behavior. Collectively, our results suggest that IQSEC3 is a key GABAergic synapse component that is directed by Npas4 activity- and ARF activity-dependent gene programs in SST-expressing interneurons to orchestrate the functional excitation-to-inhibition balance.

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Ethanol-Induced Mitochondrial Damage in Sertoli Cells is Associated with Parkin Overexpression and Activation of Mitophagy

Cells ◽

10.3390/cells8030283 ◽

2019 ◽

Vol 8 (3) ◽

pp. 283 ◽

Cited By ~ 5

Author(s):

Nabil Eid ◽

Yuko Ito ◽

Akio Horibe ◽

Yoshinori Otsuki ◽

Yoichi Kondo

Keyword(s):

Transcription Factor ◽

Sertoli Cells ◽

Molecular Mechanisms ◽

Mitochondrial Damage ◽

Control Group ◽

Protective Mechanism ◽

Adult Rats ◽

Therapeutic Implications ◽

Protein Levels ◽

Enhanced Expression

This study was conducted to elucidate the involvement of the PINK1-Parkin pathway in ethanol-induced mitophagy among Sertoli cells (SCs). In the research, adult rats were given intraperitoneal injections of ethanol (5 gm/kg) and sacrificed at various time periods within 24 h. Transmission electron microscopy was applied to reveal enhanced mitochondrial damage in SCs of the ethanol-treated rats (ETRs) in association with a significant increase in numbers of mitophagic vacuoles (mitophagosomes and autolysosomes) in contrast to very low levels in a control group treated with phosphate-buffered saline (PBS). This enhancement was ultra-structurally verified via observation of trapped mitochondria within LC3-labeled membranes, upregulation of LC3 protein levels, colocalization of LC3 and cytochrome c, and reduced expression of mitochondrial proteins. Importantly, Parkin expression was found to be upregulated in ETR SCs, specifically in mitochondria and mitophagosomes in addition to colocalization with PINK1 and pan-cathepsin, indicating augmented mitophagy. Transcription factor EB (TFEB, a transcription factor for autophagy and mitophagy proteins) was also found to be upregulated in nuclei of ETR SCs and associated with enhanced expression of iNOS. Enhanced Parkin-related mitophagy in ETR SCs may be a protective mechanism with therapeutic implications. To the authors’ knowledge, this is the first report demonstrating the ultrastructural characteristics and molecular mechanisms of Parkin-related mitophagy in ETR SCs.

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The Transcriptional Complex Sp1/KMT2A by Up-Regulating Restrictive Element 1 Silencing Transcription Factor Accelerates Methylmercury-Induced Cell Death in Motor Neuron-Like NSC34 Cells Overexpressing SOD1-G93A

Frontiers in Neuroscience ◽

10.3389/fnins.2021.771580 ◽

2021 ◽

Vol 15 ◽

Author(s):

Natascia Guida ◽

Luca Sanguigno ◽

Luigi Mascolo ◽

Lucrezia Calabrese ◽

Angelo Serani ◽

...

Keyword(s):

Cell Death ◽

Transcription Factor ◽

Motor Neuron ◽

Molecular Mechanisms ◽

Gene Promoter ◽

Promoter Sequence ◽

Protein Levels ◽

Lysine Methyltransferase ◽

Transcriptional Complex ◽

Lateral Sclerosis

Methylmercury (MeHg) exposure has been related to amyotrophic lateral sclerosis (ALS) pathogenesis and molecular mechanisms of its neurotoxicity has been associated to an overexpression of the Restrictive Element 1 Silencing Transcription factor (REST). Herein, we evaluated the possibility that MeHg could accelerate neuronal death of the motor neuron-like NSC34 cells transiently overexpressing the human Cu2+/Zn2+superoxide dismutase 1 (SOD1) gene mutated at glycine 93 (SOD1-G93A). Indeed, SOD1-G93A cells exposed to 100 nM MeHg for 24 h showed a reduction in cell viability, as compared to cells transfected with empty vector or with unmutated SOD1 construct. Interestingly, cell survival reduction in SOD1-G93A cells was associated with an increase of REST mRNA and protein levels. Furthermore, MeHg increased the expression of the transcriptional factor Sp1 and promoted its binding to REST gene promoter sequence. Notably, Sp1 knockdown reverted MeHg-induced REST increase. Co-immunoprecipitation experiments demonstrated that Sp1 physically interacted with the epigenetic writer Lysine-Methyltransferase-2A (KMT2A). Moreover, knocking-down of KMT2A reduced MeHg-induced REST mRNA and protein increase in SOD1-G93A cells. Finally, we found that MeHg-induced REST up-regulation triggered necropoptotic cell death, monitored by RIPK1 increased protein expression. Interestingly, REST knockdown or treatment with the necroptosis inhibitor Necrostatin-1 (Nec) decelerated MeH-induced cell death in SOD1-G93A cells. Collectively, this study demonstrated that MeHg hastens necroptotic cell death in SOD1-G93A cells via Sp1/KMT2A complex, that by epigenetic mechanisms increases REST gene expression.

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