1
|
Agas A, Kalluru J, Leiser B, Garcia R, Kataru H, Haorah J. Possible mechanisms of HIV neuro-infection in alcohol use: Interplay of oxidative stress, inflammation, and energy interruption. Alcohol 2021; 94:25-41. [PMID: 33864851 DOI: 10.1016/j.alcohol.2021.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 03/05/2021] [Accepted: 04/01/2021] [Indexed: 11/21/2022]
Abstract
Alcohol use and HIV-1 infection have a pervasive impact on brain function, which extends to the requirement, distribution, and utilization of energy within the central nervous system. This effect on neuroenergetics may explain, in part, the exacerbation of HIV-1 disease under the influence of alcohol, particularly the persistence of HIV-associated neurological complications. The objective of this review article is to highlight the possible mechanisms of HIV/AIDS progression in alcohol users from the perspective of oxidative stress, neuroinflammation, and interruption of energy metabolism. These include the hallmark of sustained immune cell activation and high metabolic energy demand by HIV-1-infected cells in the central nervous system, with at-risk alcohol use. Here, we discussed the point that the increase in energy supply requirement by HIV-1-infected neuroimmune cells as well as the deterrence of nutrient uptake across the blood-brain barrier significantly depletes the energy source and neuro-environment homeostasis in the CNS. We also described the mechanistic idea that comorbidity of HIV-1 infection and alcohol use can cause a metabolic shift and redistribution of energy usage toward HIV-1-infected neuroimmune cells, as shown in neuropathological evidence. Under such an imbalanced neuro-environment, meaningless energy waste is expected in infected cells, along with unnecessary malnutrition in non-infected neuronal cells, which is likely to accelerate HIV neuro-infection progression in alcohol use. Thus, it will be important to consider the factor of nutrients/energy imbalance in formulating treatment strategies to help impede the progression of HIV-1 disease and associated neurological disorders in alcohol use.
Collapse
|
2
|
Zhang B, Zou J, Zhang Q, Wang Z, Wang N, He S, Zhao Y, Naman CB. Progress in the Development of Eukaryotic Elongation Factor 2 Kinase (eEF2K) Natural Product and Synthetic Small Molecule Inhibitors for Cancer Chemotherapy. Int J Mol Sci 2021; 22:2408. [PMID: 33673713 DOI: 10.3390/ijms22052408] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 02/24/2021] [Accepted: 02/24/2021] [Indexed: 12/12/2022] Open
Abstract
Eukaryotic elongation factor 2 kinase (eEF2K or Ca2+/calmodulin-dependent protein kinase, CAMKIII) is a new member of an atypical α-kinase family different from conventional protein kinases that is now considered as a potential target for the treatment of cancer. This protein regulates the phosphorylation of eukaryotic elongation factor 2 (eEF2) to restrain activity and inhibit the elongation stage of protein synthesis. Mounting evidence shows that eEF2K regulates the cell cycle, autophagy, apoptosis, angiogenesis, invasion, and metastasis in several types of cancers. The expression of eEF2K promotes survival of cancer cells, and the level of this protein is increased in many cancer cells to adapt them to the microenvironment conditions including hypoxia, nutrient depletion, and acidosis. The physiological function of eEF2K and its role in the development and progression of cancer are here reviewed in detail. In addition, a summary of progress for in vitro eEF2K inhibitors from anti-cancer drug discovery research in recent years, along with their structure-activity relationships (SARs) and synthetic routes or natural sources, is also described. Special attention is given to those inhibitors that have been already validated in vivo, with the overall aim to provide reference context for the further development of new first-in-class anti-cancer drugs that target eEF2K.
Collapse
|
3
|
Chang C, Su C, Gean P. Mechanism underlying NMDA blockade-induced inhibition of aggression in post-weaning socially isolated mice. Neuropharmacology 2018; 143:95-105. [DOI: 10.1016/j.neuropharm.2018.09.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 08/22/2018] [Accepted: 09/11/2018] [Indexed: 11/18/2022]
|
4
|
Pakri Mohamed RM, Mokhtar MH, Yap E, Hanim A, Abdul Wahab N, Jaffar FHF, Kumar J. Ethanol-Induced Changes in PKCε: From Cell to Behavior. Front Neurosci 2018; 12:244. [PMID: 29706864 PMCID: PMC5907685 DOI: 10.3389/fnins.2018.00244] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 03/28/2018] [Indexed: 11/20/2022] Open
Abstract
The long-term binge intake of ethanol causes neuroadaptive changes that lead to drinkers requiring higher amounts of ethanol to experience its effects. This neuroadaptation can be partly attributed to the modulation of numerous neurotransmitter receptors by the various protein kinases C (PKCs). PKCs are enzymes that control cellular activities by regulating other proteins via phosphorylation. Among the various isoforms of PKC, PKCε is the most implicated in ethanol-induced biochemical and behavioral changes. Ethanol exposure causes changes to PKCε expression and localization in various brain regions that mediate addiction-favoring plasticity. Ethanol works in conjunction with numerous upstream kinases and second messenger activators to affect cellular PKCε expression. Chauffeur proteins, such as receptors for activated C kinase (RACKs), cause the translocation of PKCε to aberrant sites and mediate ethanol-induced changes. In this article, we aim to review the following: the general structure and function of PKCε, ethanol-induced changes in PKCε expression, the regulation of ethanol-induced PKCε activities in DAG-dependent and DAG-independent environments, the mechanisms underlying PKCε-RACKε translocation in the presence of ethanol, and the existing literature on the role of PKCε in ethanol-induced neurobehavioral changes, with the goal of creating a working model upon which further research can build.
Collapse
Affiliation(s)
| | - Mohd H. Mokhtar
- Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Ernie Yap
- Department of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Athirah Hanim
- Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Norhazlina Abdul Wahab
- Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Farah H. F. Jaffar
- Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Jaya Kumar
- Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| |
Collapse
|
5
|
Tsuji-Tamura K, Ogawa M. Dual inhibition of mTORC1 and mTORC2 perturbs cytoskeletal organization and impairs endothelial cell elongation. Biochem Biophys Res Commun 2018; 497:326-331. [DOI: 10.1016/j.bbrc.2018.02.080] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 02/08/2018] [Indexed: 02/03/2023]
|
6
|
Gritsyna YV, Salmov NN, Bobylev AG, Ulanova AD, Kukushkin NI, Podlubnaya ZA, Vikhlyantsev IM. Increased Autolysis ofμ-Calpain in Skeletal Muscles of Chronic Alcohol-Fed Rats. Alcohol Clin Exp Res 2017; 41:1686-1694. [DOI: 10.1111/acer.13476] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 08/04/2017] [Indexed: 01/31/2023]
Affiliation(s)
- Yulia V. Gritsyna
- Laboratory of Structure and Functions of Muscle Proteins; Institute of Theoretical and Experimental Biophysics; Russian Academy of Sciences; Pushchino Russia
| | - Nikolay N. Salmov
- Laboratory of Structure and Functions of Muscle Proteins; Institute of Theoretical and Experimental Biophysics; Russian Academy of Sciences; Pushchino Russia
| | - Alexander G. Bobylev
- Laboratory of Structure and Functions of Muscle Proteins; Institute of Theoretical and Experimental Biophysics; Russian Academy of Sciences; Pushchino Russia
- Pushchino State Institute of Natural Science; Pushchino Russia
| | - Anna D. Ulanova
- Laboratory of Structure and Functions of Muscle Proteins; Institute of Theoretical and Experimental Biophysics; Russian Academy of Sciences; Pushchino Russia
- Pushchino State Institute of Natural Science; Pushchino Russia
| | - Nikolay I. Kukushkin
- Laboratory of Cell Cultures and Cell Engineering; Institute of Cell Biophysics; Russian Academy of Sciences; Pushchino Russia
| | - Zoya A. Podlubnaya
- Laboratory of Structure and Functions of Muscle Proteins; Institute of Theoretical and Experimental Biophysics; Russian Academy of Sciences; Pushchino Russia
- Pushchino State Institute of Natural Science; Pushchino Russia
| | - Ivan M. Vikhlyantsev
- Laboratory of Structure and Functions of Muscle Proteins; Institute of Theoretical and Experimental Biophysics; Russian Academy of Sciences; Pushchino Russia
- Pushchino State Institute of Natural Science; Pushchino Russia
| |
Collapse
|
7
|
Cozzoli DK, Courson J, Rostock C, Campbell RR, Wroten MG, McGregor H, Caruana AL, Miller BW, Hu JH, Zhang PW, Xiao B, Worley PF, Crabbe JC, Finn DA, Szumlinski KK. Protein Kinase C Epsilon Activity in the Nucleus Accumbens and Central Nucleus of the Amygdala Mediates Binge Alcohol Consumption. Biol Psychiatry 2016; 79:443-51. [PMID: 25861702 PMCID: PMC4561036 DOI: 10.1016/j.biopsych.2015.01.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 01/09/2015] [Accepted: 01/20/2015] [Indexed: 12/11/2022]
Abstract
BACKGROUND Protein kinase C epsilon (PKCε) is emerging as a potential target for the development of pharmacotherapies to treat alcohol use disorders, yet little is known regarding how a history of a highly prevalent form of drinking, binge alcohol intake, influences enzyme priming or the functional relevance of kinase activity for excessive alcohol intake. METHODS Immunoblotting was employed on tissue from subregions of the nucleus accumbens (NAc) and the amygdala to examine both idiopathic and binge drinking-induced changes in constitutive PKCε priming. The functional relevance of PKCε translocation for binge drinking and determination of potential upstream signaling pathways involved were investigated using neuropharmacologic approaches within the context of two distinct binge drinking procedures, drinking in the dark and scheduled high alcohol consumption. RESULTS Binge alcohol drinking elevated p(Ser729)-PKCε levels in both the NAc and the central nucleus of the amygdala (CeA). Moreover, immunoblotting studies of selectively bred and transgenic mouse lines revealed a positive correlation between the propensity to binge drink alcohol and constitutive p(Ser729)-PKCε levels in the NAc and CeA. Finally, neuropharmacologic inhibition of PKCε translocation within both regions reduced binge alcohol consumption in a manner requiring intact group 1 metabotropic glutamate receptors, Homer2, phospholipase C, and/or phosphotidylinositide-3 kinase function. CONCLUSIONS Taken together, these data indicate that PKCε signaling in both the NAc and CeA is a major contributor to binge alcohol drinking and to the genetic propensity to consume excessive amounts of alcohol.
Collapse
Affiliation(s)
- Debra K. Cozzoli
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-9660, U.S.A,Department of Behavioral Neuroscience, Oregon Health & Science University and Portland Alcohol Research Center, VA Portland Healthcare System, Portland, OR 97239, U.S.A
| | - Justin Courson
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-9660, U.S.A
| | - Charlotte Rostock
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-9660, U.S.A
| | - Rianne R. Campbell
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-9660, U.S.A
| | - Melissa G. Wroten
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-9660, U.S.A
| | - Hadley McGregor
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-9660, U.S.A
| | - Amanda L. Caruana
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-9660, U.S.A
| | - Bailey W. Miller
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-9660, U.S.A
| | - Jia-Hua Hu
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, U.S.A
| | - Ping Wu Zhang
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, U.S.A
| | - Bo Xiao
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, U.S.A
| | - Paul F. Worley
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, U.S.A
| | - John C. Crabbe
- Department of Behavioral Neuroscience, Oregon Health & Science University and Portland Alcohol Research Center, VA Portland Healthcare System, Portland, OR 97239, U.S.A
| | - Deborah A. Finn
- Department of Behavioral Neuroscience, Oregon Health & Science University and Portland Alcohol Research Center, VA Portland Healthcare System, Portland, OR 97239, U.S.A
| | - Karen K. Szumlinski
- Department of Psychological and Brain Sciences and the Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-9660, U.S.A
| |
Collapse
|
8
|
López-Domínguez JA, Cánovas Á, Medrano JF, Islas-Trejo A, Kim K, Taylor SL, Villalba JM, López-Lluch G, Navas P, Ramsey JJ. Omega-3 fatty acids partially revert the metabolic gene expression profile induced by long-term calorie restriction. Exp Gerontol 2016; 77:29-37. [PMID: 26875793 DOI: 10.1016/j.exger.2016.02.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 02/03/2016] [Accepted: 02/08/2016] [Indexed: 11/18/2022]
Abstract
Calorie restriction (CR) consistently extends longevity and delays age-related diseases across several animal models. We have previously shown that different dietary fat sources can modulate life span and mitochondrial ultrastructure, function and membrane fatty acid composition in mice maintained on a 40% CR. In particular, animals consuming lard as the main fat source (CR-Lard) lived longer than CR mice consuming diets with soybean oil (CR-Soy) or fish oil (CR-Fish) as the predominant lipid source. In the present work, a transcriptomic analysis in the liver and skeletal muscle was performed in order to elucidate possible mechanisms underlying the changes in energy metabolism and longevity induced by dietary fat in CR mice. After 8 months of CR, transcription downstream of several mediators of inflammation was inhibited in liver. In contrast, proinflammatory signaling was increased in the CR-Fish versus other CR groups. Dietary fish oil induced a gene expression pattern consistent with increased transcriptional regulation by several cytokines (TNF, GM-CSF, TGF-β) and sex hormones when compared to the other CR groups. The CR-Fish also had lower expression of genes involved in fatty acid biosynthesis and increased expression of mitochondrial and peroxisomal fatty acid β-oxidation genes than the other CR diet groups. Our data suggest that a diet high in n-3 PUFA, partially reverts CR-related changes in gene expression of key processes, such as inflammation and steroid hormone signaling, and this may mitigate life span extension with CR in mice consuming diets high in fish oil.
Collapse
Affiliation(s)
| | - Ángela Cánovas
- Department of Animal Science, University of California, Davis, USA
| | - Juan F Medrano
- Department of Animal Science, University of California, Davis, USA
| | - Alma Islas-Trejo
- Department of Animal Science, University of California, Davis, USA
| | - Kyoungmi Kim
- Department of Public Health, School of Medicine, University of California, Davis, USA
| | - Sandra L Taylor
- Department of Public Health, School of Medicine, University of California, Davis, USA
| | - José Manuel Villalba
- Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba, Campus de Excelencia Internacional Agroalimentario, ceiA3, Spain
| | - Guillermo López-Lluch
- Centro Andaluz de Biología del Desarrollo (CABD), Universidad Pablo de Olavide-CSIC, CIBERER, Instituto de Salud Carlos III, Sevilla, Spain
| | - Plácido Navas
- Centro Andaluz de Biología del Desarrollo (CABD), Universidad Pablo de Olavide-CSIC, CIBERER, Instituto de Salud Carlos III, Sevilla, Spain
| | - Jon J Ramsey
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, USA
| |
Collapse
|
9
|
Tsuji-Tamura K, Ogawa M. Inhibition of the PI3K-Akt and mTORC1 signaling pathways promotes the elongation of vascular endothelial cells. J Cell Sci 2016; 129:1165-78. [PMID: 26826185 DOI: 10.1242/jcs.178434] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 01/21/2016] [Indexed: 12/20/2022] Open
Abstract
Endothelial cell morphology needs to be properly regulated during angiogenesis. Vascular endothelial growth factor (VEGF) induces endothelial cell elongation, which promotes sprouting of pre-existing vessels. However, therapeutic angiogenesis using VEGF has been hampered by side effects such as elevated vascular permeability. Here, we attempted to induce endothelial cell elongation without an overdose of VEGF. By screening a library of chemical inhibitors, we identified phosphatidylinositol 3-kinase (PI3K)-Akt pathway inhibitors and mammalian target of rapamycin complex 1 (mTORC1) inhibitors as potent inducers of endothelial cell elongation. The elongation required VEGF at a low concentration, which was insufficient to elicit the same effect by itself. The elongation also depended on Foxo1, a transcription factor indispensable for angiogenesis. Interestingly, the Foxo1 dependency of the elongation was overridden by inhibition of mTORC1, but not by PI3K-Akt, under stimulation by a high concentration of VEGF. Dual inhibition of mTORC1 and mTORC2 failed to induce cell elongation, revealing mTORC2 as a positive regulator of elongation. Our findings suggest that the PI3K-Akt-Foxo1 and mTORC1-mTORC2 pathways differentially regulate endothelial cell elongation, depending on the microenvironmental levels of VEGF.
Collapse
Affiliation(s)
- Kiyomi Tsuji-Tamura
- Department of Cell Differentiation, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan
| | - Minetaro Ogawa
- Department of Cell Differentiation, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan
| |
Collapse
|
10
|
Abstract
Alcohol abuse, either by acute intoxication or prolonged excessive consumption, leads to pathological changes in many organs and tissues including skeletal muscle. As muscle protein serves not only a contractile function but also as a metabolic reserve for amino acids, which are used to support the energy needs of other tissues, its content is tightly regulated and dynamic. This review focuses on the etiology by which alcohol perturbs skeletal muscle protein balance and thereby over time produces muscle wasting and weakness. The preponderance of data suggest that alcohol primarily impairs global protein synthesis, under basal conditions as well as in response to several anabolic stimuli including growth factors, nutrients, and muscle contraction. This inhibitory effect of alcohol is mediated, at least in part, by a reduction in mTOR kinase activity via a mechanism that remains poorly defined but likely involves altered protein-protein interactions within mTOR complex 1. Furthermore, alcohol can exacerbate the decrement in mTOR and/or muscle protein synthesis present in other catabolic states. In contrast, alcohol-induced changes in muscle protein degradation, either global or via specific modulation of the ubiquitin-proteasome or autophagy pathways, are relatively inconsistent and may be model dependent. Herein, changes produced by acute intoxication versus chronic ingestion are contrasted in relation to skeletal muscle metabolism, and limitations as well as opportunities for future research are discussed. As the proportion of more economically developed countries ages and chronic illness becomes more prevalent, a better understanding of the etiology of biomedical consequences of alcohol use disorders is warranted.
Collapse
Affiliation(s)
- Jennifer L Steiner
- Department of Cellular and Molecular Physiology, Pennsylvania State College of Medicine, Hershey, Pennsylvania
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Pennsylvania State College of Medicine, Hershey, Pennsylvania
| |
Collapse
|
11
|
Foster HA, Davies J, Pink RC, Turkcigdem S, Goumenou A, Carter DR, Saunders NJ, Thomas P, Karteris E. The human myometrium differentially expresses mTOR signalling components before and during pregnancy: evidence for regulation by progesterone. J Steroid Biochem Mol Biol 2014; 139:166-72. [PMID: 23541542 PMCID: PMC3855612 DOI: 10.1016/j.jsbmb.2013.02.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 02/07/2013] [Accepted: 02/24/2013] [Indexed: 10/27/2022]
Abstract
Emerging studies implicate the signalling of the mammalian target of rapamycin (mTOR) in a number of reproductive functions. To this date, there are no data regarding the expression of mTOR signalling components in the human myometrium during pregnancy. We hypothesized that mTOR-related genes might be differentially expressed in term or preterm labour as well as in labour or non-labour myometria during pregnancy. Using quantitative RT-PCR we demonstrate for first time that there is a significant downregulation of mTOR, DEPTOR, and Raptor in preterm labouring myometria when compared to non-pregnant tissues taken from the same area (lower segment). We used an immortalized myometrial cell line (ULTR) as an in vitro model to dissect further mTOR signalling. In ULTR cells DEPTOR and Rictor had a cytoplasmic distribution, whereas mTOR and Raptor were detected in the cytoplasm and the nucleus, indicative of mTORC1 shuttling. Treatment with inflammatory cytokines caused only minor changes in gene expression of these components, whereas progesterone caused significant down-regulation. We performed a non-biased gene expression analysis of ULTR cells using Nimblegen human gene expression microarray (n=3), and selected genes were validated by quantitative RT-PCR in progesterone treated myometrial cells. Progesterone significantly down-regulated key components of the mTOR pathway. We conclude that the human myometrium differentially expresses mTOR signalling components and they can be regulated by progesterone. This article is part of a Special Issue entitled 'Pregnancy and Steroids'.
Collapse
Affiliation(s)
- Helen A Foster
- Biosciences, Centre for Cell and Chromosome Biology, Brunel University, Uxbridge UB8 3PH, UK
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Gritsyna YV, Salmov NN, Vikhlyantsev IM, Ulanova AD, Sharapov MG, Teplova VV, Podlubnaya ZA. Changes in gene expression and titin (connectin) content in striated muscles of chronically alcoholized rats. Mol Biol 2013. [DOI: 10.1134/s0026893313060058] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
13
|
Hong-Brown LQ, Brown CR, Navaratnarajah M, Lang CH. Activation of AMPK/TSC2/PLD by alcohol regulates mTORC1 and mTORC2 assembly in C2C12 myocytes. Alcohol Clin Exp Res 2013; 37:1849-61. [PMID: 23895284 DOI: 10.1111/acer.12174] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 04/03/2013] [Indexed: 01/02/2023]
Abstract
BACKGROUND Ethanol (EtOH) decreases muscle protein synthesis, and this is associated with reduced mammalian target of rapamycin complex (mTORC)1 and increased mTORC2 activities. In contrast, phospholipase D (PLD) and its metabolite phosphatidic acid (PA) positively regulate mTORC1 signaling, whereas their role in mTORC2 function is less well defined. Herein, we examine the role that PLD and PA play in EtOH-mediated mTOR signaling. METHODS C2C12 myoblasts were incubated with EtOH for 18 to 24 hours. For PA experiments, cells were pretreated with the drug for 25 minutes followed by 50-minute incubation with PA in the presence or absence of EtOH. The phosphorylation state of various proteins was assessed by immunoblotting. Protein-protein interactions were determined by immunoprecipitation and immunoblotting. PLD activity was measured using the Amplex Red PLD assay kit. PA concentrations were determined with a total PA assay kit. RESULTS PA levels and PLD activity increased in C2C12 myocytes exposed to EtOH (100 mM). Increased PLD activity was blocked by inhibitors of AMP-activated protein kinase (AMPK) (compound C) and phosphoinositide 3-kinase (PI3K) (wortmannin). Likewise, suppression of PLD activity with CAY10594 prevented EtOH-induced Akt (S473) phosphorylation. PLD inhibition also enhanced the binding of Rictor to mSin1 and the negative regulatory proteins Deptor and 14-3-3. Addition of PA to myocytes decreased Akt phosphorylation, but changes in mTORC2 activity were not associated with altered binding of complex members and 14-3-3. PA increased S6K1 phosphorylation, with the associated increase in mTORC1 activity being regulated by reduced phosphorylation of AMPKα (T172) and its target tuberous sclerosis protein complex (TSC)2 (S1387). This resulted in increased Rheb and RagA/RagC GTPase interactions with mTOR, as well as suppression of mTORC2. CONCLUSIONS EtOH-induced increases in PLD activity and PA may partially counterbalance the adverse effects of this agent. EtOH and PA regulate mTORC1 via a PI3K/AMPK/TSC2/PLD signaling cascade. PA stimulates mTORC1 function and suppresses activation of mTORC2 as part of an mTORC1/2 feedback loop.
Collapse
Affiliation(s)
- Ly Q Hong-Brown
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | | | | | | |
Collapse
|