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Khoury R, Saad J, Jabre V, Ghayad LM, Khalifeh M, Houbeika R, El Ahmad P, Mezher A, El Masri D, Haddad Z, Eid F, Barmo N, Nasrallah P, Sleiman SF, Stephan JS. Autophagy regulates the release of exercise factors and their beneficial effects on spatial memory recall. Heliyon 2023; 9:e14705. [PMID: 37025840 PMCID: PMC10070545 DOI: 10.1016/j.heliyon.2023.e14705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 02/28/2023] [Accepted: 03/15/2023] [Indexed: 03/29/2023] Open
Abstract
Exercise promotes learning and memory recall as well as rescues cognitive decline associated with aging. The positive effects of exercise are mediated by circulatory factors that predominantly increase Brain Derived Neurotrophic Factor (BDNF) signaling in the hippocampus. Identifying the pathways that regulate the release of the circulatory factors by various tissues during exercise and that mediate hippocampal Mus musculus Bdnf expression will allow us to harness the therapeutic potential of exercise. Here, we report that two weeks of voluntary exercise in male mice activates autophagy in the hippocampus by increasing LC3B protein levels (p = 0.0425) and that autophagy is necessary for exercise-induced spatial learning and memory retention (p < 0.001; exercise + autophagy inhibitor chloroquine CQ versus exercise). We place autophagy downstream of hippocampal BDNF signaling and identify a positive feedback activation between the pathways. We also assess whether the modulation of autophagy outside the nervous system is involved in mediating exercise's effect on learning and memory recall. Indeed, plasma collected from young exercise mice promote spatial learning (p = 0.0446; exercise versus sedentary plasma) and memory retention in aged inactive mice (p = 0.0303; exercise versus sedentary plasma), whereas plasma collected from young exercise mice that received the autophagy inhibitor chloroquine diphosphate failed to do so. We show that the release of exercise factors that reverse the symptoms of aging into the circulation is dependent on the activation of autophagy in young animals. Indeed, we show that the release of the exercise factor, beta-hydroxybutyrate (DBHB), into the circulation, is autophagy-dependent and that DBHB promotes spatial learning and memory formation (p = 0.0005) by inducing hippocampal autophagy (p = 0.0479). These results implicate autophagy in peripheral tissues and in the hippocampus in mediating the effects of exercise on learning and memory recall and identify DBHB as a candidate endogenous exercise factor whose release and positive effects are autophagy-dependent.
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Fakhoury M, Eid F, El Ahmad P, Khoury R, Mezher A, El Masri D, Haddad Z, Zoghbi Y, Ghayad LM, Sleiman SF, Stephan JS. Exercise and Dietary Factors Mediate Neural Plasticity Through Modulation of BDNF Signaling. Brain Plast 2022; 8:121-128. [DOI: 10.3233/bpl-220140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2022] [Indexed: 11/15/2022] Open
Abstract
The term “neural plasticity” was first used to describe non-pathological changes in neuronal structure. Today, it is generally accepted that the brain is a dynamic system whose morphology and function is influenced by a variety of factors including stress, diet, and exercise. Neural plasticity involves learning and memory, the synthesis of new neurons, the repair of damaged connections, and several other compensatory mechanisms. It is altered in neurodegenerative disorders and following damage to the central or peripheral nervous system. Understanding the mechanisms that regulate neural plasticity in both healthy and diseased states is of significant importance to promote cognition and develop rehabilitation techniques for functional recovery after injury. In this minireview, we will discuss the mechanisms by which environmental factors promote neural plasticity with a focus on exercise- and diet-induced factors. We will highlight the known circulatory factors that are released in response to exercise and discuss how all factors activate pathways that converge in part on the activation of BDNF signaling. We propose to harness the therapeutic potential of exercise by using BDNF as a biomarker to identify novel endogenous factors that promote neural plasticity. We also discuss the importance of combining exercise factors with dietary factors to develop a lifestyle pill for patients afflicted by CNS disorders.
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Affiliation(s)
- Marc Fakhoury
- Biological Sciences Program, Lebanese American University, Byblos, Lebanon
| | - Fady Eid
- Biological Sciences Program, Lebanese American University, Byblos, Lebanon
| | - Perla El Ahmad
- Biological Sciences Program, Lebanese American University, Byblos, Lebanon
| | - Reine Khoury
- Biological Sciences Program, Lebanese American University, Byblos, Lebanon
| | - Amar Mezher
- Biological Sciences Program, Lebanese American University, Byblos, Lebanon
| | - Diala El Masri
- Biological Sciences Program, Lebanese American University, Byblos, Lebanon
| | - Zena Haddad
- Biological Sciences Program, Lebanese American University, Byblos, Lebanon
| | - Yara Zoghbi
- Biological Sciences Program, Lebanese American University, Byblos, Lebanon
| | - Litsa Maria Ghayad
- Biological Sciences Program, Lebanese American University, Byblos, Lebanon
| | - Sama F. Sleiman
- Biological Sciences Program, Lebanese American University, Byblos, Lebanon
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3
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Stephan JS, Sleiman SF. Exercise Factors Released by the Liver, Muscle, and Bones Have Promising Therapeutic Potential for Stroke. Front Neurol 2021; 12:600365. [PMID: 34108925 PMCID: PMC8181424 DOI: 10.3389/fneur.2021.600365] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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: 08/29/2020] [Accepted: 05/03/2021] [Indexed: 01/15/2023] Open
Abstract
Stroke is one of the leading causes of death and disability in the world. Stroke not only affects the patients, but also their families who serve as the primary caregivers. Discovering novel therapeutic targets for stroke is crucial both from a quality of life perspective as well as from a health economic perspective. Exercise is known to promote neuroprotection in the context of stroke. Indeed, exercise induces the release of blood-borne factors that promote positive effects on the brain. Identifying the factors that mediate the positive effects of exercise after ischemic stroke is crucial for the quest for novel therapies. This approach will yield endogenous molecules that normally cross the blood brain barrier (BBB) and that can mimic the effects of exercise. In this minireview, we will discuss the roles of exercise factors released by the liver such as beta-hydroxybutyrate (DBHB), by the muscle such as lactate and irisin and by the bones such as osteocalcin. We will also address their therapeutic potential in the context of ischemic stroke.
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Affiliation(s)
- Joseph S Stephan
- School of Medicine, Lebanese American University, Byblos, Lebanon
| | - Sama F Sleiman
- Biology Program, Lebanese American University, Byblos, Lebanon
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Nasrallah P, Haidar EA, Stephan JS, El Hayek L, Karnib N, Khalifeh M, Barmo N, Jabre V, Houbeika R, Ghanem A, Nasser J, Zeeni N, Bassil M, Sleiman SF. Branched-chain amino acids mediate resilience to chronic social defeat stress by activating BDNF/TRKB signaling. Neurobiol Stress 2019; 11:100170. [PMID: 31193350 PMCID: PMC6526306 DOI: 10.1016/j.ynstr.2019.100170] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [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: 02/27/2019] [Revised: 05/10/2019] [Accepted: 05/11/2019] [Indexed: 02/07/2023] Open
Abstract
How individuals respond to chronic stress varies. Susceptible individuals ultimately develop depression; whereas resilient individuals live normally. In this study, our objective was to examine the effect of branched-chain amino acids (BCAA), commonly used by athletes, on susceptibility to stress. Male C57BL/6 mice were subjected to daily defeat sessions by a CD1 aggressor, for 10 days. On day11, the behavior of mice was assessed using the social interaction test, elevated plus maze and open field. Mice received the BCAA leucine, isoleucine or valine before each defeat session. Furthermore, we examined whether BCAA regulate brain derived neurotrophic factor (BDNF) signaling by using a brain-permeable tropomyosin receptor kinase B (TRKB) inhibitor, ANA-12. We also tested the effect of voluntary exercise and high protein diets on susceptibility to stress. Mice exposed to chronic stress displayed increased susceptibility and social avoidance. BCAA promoted resilience to chronic stress, rescued social avoidance behaviors and increased hippocampal BDNF levels and TRKB activation. Inhibition of TRKB signaling abolished the ability of BCAA to promote resilience to stress and to rescue social avoidance. Interestingly, we found that BCAA activate the exercise-regulated PGC1a/FNDC5 pathway known to induce hippocampal BDNF signaling. Although both voluntary exercise and BCAA promoted resilience to stress, combining them did not yield synergistic effects confirming that they affect similar pathways. We also discovered that high protein diets mimic the effect of BCAA by rescuing social deficits induced by chronic stress and increase Bdnf expression in the hippocampus. Our data indicate that BCAA, exercise and high protein diets rescue susceptibility to stress by activating the hippocampal BDNF/TRKB signaling. BCAA promote resilience to stress and rescue social avoidance via activation of hippocampal BDNF/TRKB signaling. BCAA induce hippocampal BDNF/TRKB signaling by activating the exercise-regulated PGC1a/FNDC5 pathway. BCAA and voluntary exercise affect similar pathways. HPD promote resilience to stress, rescue social avoidance and induce hippocampal Bdnf expression.
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Affiliation(s)
- Patrick Nasrallah
- Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Edwina Abou Haidar
- Molecular Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Joseph S Stephan
- School of Medicine, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Lauretta El Hayek
- Molecular Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Nabil Karnib
- Molecular Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Mohamad Khalifeh
- Molecular Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Nour Barmo
- Molecular Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Vanessa Jabre
- Molecular Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Rouba Houbeika
- Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Anthony Ghanem
- Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Jason Nasser
- Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Nadine Zeeni
- Nutrition Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Maya Bassil
- Nutrition Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Sama F Sleiman
- Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon.,Molecular Biology Program, Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
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5
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Karnib N, El-Ghandour R, El Hayek L, Nasrallah P, Khalifeh M, Barmo N, Jabre V, Ibrahim P, Bilen M, Stephan JS, Holson EB, Ratan RR, Sleiman SF. Lactate is an antidepressant that mediates resilience to stress by modulating the hippocampal levels and activity of histone deacetylases. Neuropsychopharmacology 2019; 44:1152-1162. [PMID: 30647450 PMCID: PMC6461925 DOI: 10.1038/s41386-019-0313-z] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [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: 08/10/2018] [Revised: 12/27/2018] [Accepted: 12/30/2018] [Indexed: 11/09/2022]
Abstract
Chronic stress promotes depression in some individuals, but has no effect in others. Susceptible individuals exhibit social avoidance and anxious behavior and ultimately develop depression, whereas resilient individuals live normally. Exercise counteracts the effects of stress. Our objective was to examine whether lactate, a metabolite produced during exercise and known to reproduce specific brain exercise-related changes, promotes resilience to stress and acts as an antidepressant. To determine whether lactate promotes resilience to stress, male C57BL/6 mice experienced daily defeat by a CD-1 aggressor, for 10 days. On the 11th day, mice were subjected to behavioral tests. Mice received lactate before each defeat session. When compared with control mice, mice exposed to stress displayed increased susceptibility, social avoidance and anxiety. Lactate promoted resilience to stress and rescued social avoidance and anxiety by restoring hippocampal class I histone deacetylase (HDAC) levels and activity, specifically HDAC2/3. To determine whether lactate is an antidepressant, mice only received lactate from days 12-25 and a second set of behavioral tests was conducted on day 26. In this paradigm, we examined whether lactate functions by regulating HDACs using co-treatment with CI-994, a brain-permeable class I HDAC inhibitor. When administered after the establishment of depression, lactate behaved as antidepressant. In this paradigm, lactate regulated HDAC5 and not HDAC2/3 levels. On the contrary, HDAC2/3 inhibition was antidepressant-like. This indicates that lactate mimics exercise's effects and rescues susceptibility to stress by modulating HDAC2/3 activity and suggests that HDAC2/3 play opposite roles before and after establishment of susceptibility to stress.
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Affiliation(s)
- Nabil Karnib
- 0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Molecular Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Rim El-Ghandour
- 0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Molecular Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Lauretta El Hayek
- 0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Molecular Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Patrick Nasrallah
- 0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Mohamad Khalifeh
- 0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Molecular Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Nour Barmo
- 0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Molecular Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Vanessa Jabre
- 0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Molecular Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Pascale Ibrahim
- 0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Molecular Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Maria Bilen
- 0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Molecular Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Joseph S. Stephan
- 0000 0001 2324 5973grid.411323.6School of Medicine, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Edward B. Holson
- Atlas Venture, Cambridge, MA USA ,grid.66859.34Stanley Center for Psychiatric Research, The Broad Institute of MIT and Harvard, Cambridge, MA USA
| | - Rajiv R. Ratan
- 0000 0004 0421 4727grid.410373.2Burke Medical Research Institute, White Plains, NY USA
| | - Sama F. Sleiman
- 0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Molecular Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon ,0000 0001 2324 5973grid.411323.6Department of Natural Sciences, Biology Program, Lebanese American University, PO Box 36, Byblos, Lebanon
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6
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Karuppagounder SS, Alim I, Khim SJ, Bourassa MW, Sleiman SF, John R, Thinnes CC, Yeh TL, Demetriades M, Neitemeier S, Cruz D, Gazaryan I, Killilea DW, Morgenstern L, Xi G, Keep RF, Schallert T, Tappero RV, Zhong J, Cho S, Maxfield FR, Holman TR, Culmsee C, Fong GH, Su Y, Ming GL, Song H, Cave JW, Schofield CJ, Colbourne F, Coppola G, Ratan RR. Therapeutic targeting of oxygen-sensing prolyl hydroxylases abrogates ATF4-dependent neuronal death and improves outcomes after brain hemorrhage in several rodent models. Sci Transl Med 2016; 8:328ra29. [PMID: 26936506 DOI: 10.1126/scitranslmed.aac6008] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Disability or death due to intracerebral hemorrhage (ICH) is attributed to blood lysis, liberation of iron, and consequent oxidative stress. Iron chelators bind to free iron and prevent neuronal death induced by oxidative stress and disability due to ICH, but the mechanisms for this effect remain unclear. We show that the hypoxia-inducible factor prolyl hydroxylase domain (HIF-PHD) family of iron-dependent, oxygen-sensing enzymes are effectors of iron chelation. Molecular reduction of the three HIF-PHD enzyme isoforms in the mouse striatum improved functional recovery after ICH. A low-molecular-weight hydroxyquinoline inhibitor of the HIF-PHD enzymes, adaptaquin, reduced neuronal death and behavioral deficits after ICH in several rodent models without affecting total iron or zinc distribution in the brain. Unexpectedly, protection from oxidative death in vitro or from ICH in vivo by adaptaquin was associated with suppression of activity of the prodeath factor ATF4 rather than activation of an HIF-dependent prosurvival pathway. Together, these findings demonstrate that brain-specific inactivation of the HIF-PHD metalloenzymes with the blood-brain barrier-permeable inhibitor adaptaquin can improve functional outcomes after ICH in several rodent models.
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Affiliation(s)
- Saravanan S Karuppagounder
- Sperling Center for Hemorrhagic Stroke Recovery, Burke Medical Research Institute, White Plains, NY 10605, USA. Feil Family Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Ishraq Alim
- Sperling Center for Hemorrhagic Stroke Recovery, Burke Medical Research Institute, White Plains, NY 10605, USA. Feil Family Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Soah J Khim
- Sperling Center for Hemorrhagic Stroke Recovery, Burke Medical Research Institute, White Plains, NY 10605, USA. Feil Family Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Megan W Bourassa
- Sperling Center for Hemorrhagic Stroke Recovery, Burke Medical Research Institute, White Plains, NY 10605, USA. Feil Family Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Sama F Sleiman
- Sperling Center for Hemorrhagic Stroke Recovery, Burke Medical Research Institute, White Plains, NY 10605, USA. Feil Family Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Roseleen John
- Department of Psychology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | | | - Tzu-Lan Yeh
- Department of Chemistry, University of Oxford, OX1 3TA Oxford, UK
| | | | - Sandra Neitemeier
- Institut fuer Pharmakologie and Klinische Pharmazie, Phillips-Universitaet Marburg, D 35032 Marburg, Germany
| | - Dana Cruz
- Department of Biochemistry, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Irina Gazaryan
- Sperling Center for Hemorrhagic Stroke Recovery, Burke Medical Research Institute, White Plains, NY 10605, USA. Feil Family Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, NY 10065, USA
| | | | - Lewis Morgenstern
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Guohua Xi
- Department of Neurosurgery, University of Michigan, Ann Arbor, MI 48109, USA
| | - Richard F Keep
- Department of Neurosurgery, University of Michigan, Ann Arbor, MI 48109, USA
| | - Timothy Schallert
- Department of Psychology, University of Texas at Austin, Austin, TX 78712, USA
| | - Ryan V Tappero
- Photon Sciences Directorate, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Jian Zhong
- Sperling Center for Hemorrhagic Stroke Recovery, Burke Medical Research Institute, White Plains, NY 10605, USA. Feil Family Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Sunghee Cho
- Sperling Center for Hemorrhagic Stroke Recovery, Burke Medical Research Institute, White Plains, NY 10605, USA. Feil Family Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Frederick R Maxfield
- Department of Biochemistry, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Theodore R Holman
- Chemistry and Biochemistry, Department, University of California at Santa Cruz, Santa Cruz, CA 95064, USA
| | - Carsten Culmsee
- Institut fuer Pharmakologie and Klinische Pharmazie, Phillips-Universitaet Marburg, D 35032 Marburg, Germany
| | - Guo-Hua Fong
- Center for Vascular Biology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Yijing Su
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Guo-li Ming
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hongjun Song
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - John W Cave
- Sperling Center for Hemorrhagic Stroke Recovery, Burke Medical Research Institute, White Plains, NY 10605, USA. Feil Family Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, NY 10065, USA
| | | | - Frederick Colbourne
- Department of Psychology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Giovanni Coppola
- Department of Psychiatry, University of California at Los Angeles, CA 90095, USA
| | - Rajiv R Ratan
- Sperling Center for Hemorrhagic Stroke Recovery, Burke Medical Research Institute, White Plains, NY 10605, USA. Feil Family Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, NY 10065, USA.
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7
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Sleiman SF, Henry J, Al-Haddad R, El Hayek L, Abou Haidar E, Stringer T, Ulja D, Karuppagounder SS, Holson EB, Ratan RR, Ninan I, Chao MV. Exercise promotes the expression of brain derived neurotrophic factor (BDNF) through the action of the ketone body β-hydroxybutyrate. eLife 2016; 5. [PMID: 27253067 PMCID: PMC4915811 DOI: 10.7554/elife.15092] [Citation(s) in RCA: 407] [Impact Index Per Article: 50.9] [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: 02/08/2016] [Accepted: 05/24/2016] [Indexed: 01/01/2023] Open
Abstract
Exercise induces beneficial responses in the brain, which is accompanied by an increase in BDNF, a trophic factor associated with cognitive improvement and the alleviation of depression and anxiety. However, the exact mechanisms whereby physical exercise produces an induction in brain Bdnf gene expression are not well understood. While pharmacological doses of HDAC inhibitors exert positive effects on Bdnf gene transcription, the inhibitors represent small molecules that do not occur in vivo. Here, we report that an endogenous molecule released after exercise is capable of inducing key promoters of the Mus musculus Bdnf gene. The metabolite β-hydroxybutyrate, which increases after prolonged exercise, induces the activities of Bdnf promoters, particularly promoter I, which is activity-dependent. We have discovered that the action of β-hydroxybutyrate is specifically upon HDAC2 and HDAC3, which act upon selective Bdnf promoters. Moreover, the effects upon hippocampal Bdnf expression were observed after direct ventricular application of β-hydroxybutyrate. Electrophysiological measurements indicate that β-hydroxybutyrate causes an increase in neurotransmitter release, which is dependent upon the TrkB receptor. These results reveal an endogenous mechanism to explain how physical exercise leads to the induction of BDNF. DOI:http://dx.doi.org/10.7554/eLife.15092.001 Exercise is not only good for our physical health but it benefits our mental health and abilities too. Physical exercise can affect how much of certain proteins are made in the brain. In particular, the levels of a protein called brain derived neurotrophic factor (or BDNF for short) increase after exercise. BDNF has already been shown to enhance mental abilities at the same time as acting against anxiety and depression in mice, and might act in similar way in humans. Nevertheless, it is currently not clear how exercise increases the production of BDNF by cells in the brain. Sleiman et al. have now investigated this question by comparing mice that were allowed to use a running wheel for 30 days with control mice that did not exercise. The comparison showed that the exercising mice had higher levels of BDNF in their brains than the control mice, which confirms the results of previous studies. Next, biochemical experiments showed that this change occurred when enzymes known as histone deacetylases stopped inhibiting the production of BDNF. Therefore Sleiman et al. hypothesised that exercise might produce a chemical that itself inhibits the histone deacetylases. Indeed, the exercising mice produced more of a molecule called β-hydroxybutyrate in their livers, which travels through the blood into the brain where it could inhibit histone deacetylases. Further experiments showed that injecting β-hydroxybutyrate directly into the brains of mice led to increase in BDNF. These new findings reveal with molecular detail one way in which exercise can affect the expression of proteins in the brain. This new understanding may provide ideas for new therapies to treat psychiatric diseases, such as depression, and neurodegenerative disorders, such as Alzheimer’s disease. DOI:http://dx.doi.org/10.7554/eLife.15092.002
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Affiliation(s)
- Sama F Sleiman
- Department of Natural Sciences, Lebanese American University, Byblos, Lebanon
| | - Jeffrey Henry
- Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, United States.,Department of Cell Biology, New York University Langone Medical Center, New York, United States.,Department of Neuroscience and Physiology, New York University Langone Medical Center, New York, United States.,Department of Psychiatry, New York University Langone Medical Center, New York, United States
| | - Rami Al-Haddad
- Department of Natural Sciences, Lebanese American University, Byblos, Lebanon
| | - Lauretta El Hayek
- Department of Natural Sciences, Lebanese American University, Byblos, Lebanon
| | - Edwina Abou Haidar
- Department of Natural Sciences, Lebanese American University, Byblos, Lebanon
| | - Thomas Stringer
- Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, United States.,Department of Cell Biology, New York University Langone Medical Center, New York, United States.,Department of Neuroscience and Physiology, New York University Langone Medical Center, New York, United States.,Department of Psychiatry, New York University Langone Medical Center, New York, United States
| | - Devyani Ulja
- Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, United States.,Department of Cell Biology, New York University Langone Medical Center, New York, United States.,Department of Neuroscience and Physiology, New York University Langone Medical Center, New York, United States.,Department of Psychiatry, New York University Langone Medical Center, New York, United States
| | - Saravanan S Karuppagounder
- Burke Medical Research Institute, White Plains, United States.,Brain Mind Research Institue, Weill Medical College of Cornell University, New York, United States
| | - Edward B Holson
- Stanley Center for Psychiatric Research, The Broad Institute of MIT and Harvard, Cambridge, United States.,Atlas Venture, Cambridge, United States
| | - Rajiv R Ratan
- Burke Medical Research Institute, White Plains, United States.,Brain Mind Research Institue, Weill Medical College of Cornell University, New York, United States
| | - Ipe Ninan
- Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, United States.,Department of Cell Biology, New York University Langone Medical Center, New York, United States.,Department of Neuroscience and Physiology, New York University Langone Medical Center, New York, United States.,Department of Psychiatry, New York University Langone Medical Center, New York, United States
| | - Moses V Chao
- Skirball Institute of Biomolecular Medicine, New York University Langone Medical Center, New York, United States.,Department of Cell Biology, New York University Langone Medical Center, New York, United States.,Department of Neuroscience and Physiology, New York University Langone Medical Center, New York, United States.,Department of Psychiatry, New York University Langone Medical Center, New York, United States
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8
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Abstract
Physical exercise produces many beneficial responses in the brain, which affect
cognitive function, blood flow, neurogenesis and resistance to injury. However,
the exact mechanisms whereby exercise produces an induction in the brain are not
well understood. A significant consequence is the induction of growth factors,
such as Brain-derived Neurotrophic Factor (BDNF). Cognitive decline that occurs
with aging, as well as progression of neurodegenerative diseases, are strongly
correlated with decreases in BDNF. In this article, we discuss the properties of
neurotrophins and the mechanisms that can account for the ability of exercise to
promote brain plasticity through BDNF.
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Affiliation(s)
- Sama F Sleiman
- Department of Natural Sciences, Lebanese American University, Byblos, Lebanon
| | - Moses V Chao
- Molecular Neurobiology Program, Skirball Institute of Biomolecular Medicine, Department of Cell Biology, Physiology & Neuroscience and Psychiatry, New York University Langone Medical Center, New York, NY, USA
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9
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Olson DE, Sleiman SF, Bourassa MW, Wagner FF, Gale JP, Zhang YL, Ratan RR, Holson EB. Hydroxamate-based histone deacetylase inhibitors can protect neurons from oxidative stress via a histone deacetylase-independent catalase-like mechanism. ACTA ACUST UNITED AC 2015; 22:439-445. [PMID: 25892200 DOI: 10.1016/j.chembiol.2015.03.014] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 01/26/2015] [Accepted: 03/02/2015] [Indexed: 11/18/2022]
Abstract
Histone deacetylase (HDAC) inhibitors have shown enormous promise for treating various disease states, presumably due to their ability to modulate acetylation of histone and non-histone proteins. Many of these inhibitors contain functional groups capable of strongly chelating metal ions. We demonstrate that several members of one such class of compounds, the hydroxamate-based HDAC inhibitors, can protect neurons from oxidative stress via an HDAC-independent mechanism. This previously unappreciated antioxidant mechanism involves the in situ formation of hydroxamate-iron complexes that catalyze the decomposition of hydrogen peroxide in a manner reminiscent of catalase. We demonstrate that while many hydroxamate-containing HDAC inhibitors display a propensity for binding iron, only a subset form active catalase mimetics capable of protecting neurons from exogenous H2O2. In addition to their impact on stroke and neurodegenerative disease research, these results highlight the possibility that HDAC-independent factors might play a role in the therapeutic effects of hydroxamate-based HDAC inhibitors.
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Affiliation(s)
- David E Olson
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| | - Sama F Sleiman
- Department of Natural Sciences, Lebanese American University, PO Box 36, Byblos, Lebanon
| | - Megan W Bourassa
- Burke Medical Research Institute, White Plains, NY 10605, USA; Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Florence F Wagner
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jennifer P Gale
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Yan-Ling Zhang
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Rajiv R Ratan
- Burke Medical Research Institute, White Plains, NY 10605, USA; Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Edward B Holson
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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10
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Speer RE, Karuppagounder SS, Basso M, Sleiman SF, Kumar A, Brand D, Smirnova N, Gazaryan I, Khim SJ, Ratan RR. Hypoxia-inducible factor prolyl hydroxylases as targets for neuroprotection by "antioxidant" metal chelators: From ferroptosis to stroke. Free Radic Biol Med 2013; 62:26-36. [PMID: 23376032 PMCID: PMC4327984 DOI: 10.1016/j.freeradbiomed.2013.01.026] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [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: 09/26/2012] [Revised: 01/23/2013] [Accepted: 01/23/2013] [Indexed: 01/12/2023]
Abstract
Neurologic conditions including stroke, Alzheimer disease, Parkinson disease, and Huntington disease are leading causes of death and long-term disability in the United States, and efforts to develop novel therapeutics for these conditions have historically had poor success in translating from bench to bedside. Hypoxia-inducible factor (HIF)-1α mediates a broad, evolutionarily conserved, endogenous adaptive program to hypoxia, and manipulation of components of the HIF pathway is neuroprotective in a number of human neurological diseases and experimental models. In this review, we discuss molecular components of one aspect of hypoxic adaptation in detail and provide perspective on which targets within this pathway seem to be ripest for preventing and repairing neurodegeneration. Further, we highlight the role of HIF prolyl hydroxylases as emerging targets for the salutary effects of metal chelators on ferroptosis in vitro as well in animal models of neurological diseases.
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Affiliation(s)
- Rachel E Speer
- Graduate Program in Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Burke Medical Research Institute, White Plains, NY 10605, USA
| | - Saravanan S Karuppagounder
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Burke Medical Research Institute, White Plains, NY 10605, USA
| | - Manuela Basso
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Burke Medical Research Institute, White Plains, NY 10605, USA
| | - Sama F Sleiman
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Burke Medical Research Institute, White Plains, NY 10605, USA
| | - Amit Kumar
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Burke Medical Research Institute, White Plains, NY 10605, USA
| | - David Brand
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Burke Medical Research Institute, White Plains, NY 10605, USA
| | - Natalya Smirnova
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Burke Medical Research Institute, White Plains, NY 10605, USA
| | - Irina Gazaryan
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Burke Medical Research Institute, White Plains, NY 10605, USA
| | - Soah J Khim
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Burke Medical Research Institute, White Plains, NY 10605, USA
| | - Rajiv R Ratan
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA; Burke Medical Research Institute, White Plains, NY 10605, USA.
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11
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Karuppagounder SS, Basso M, Sleiman SF, Ma TC, Speer RE, Smirnova NA, Gazaryan IG, Ratan RR. In vitro ischemia suppresses hypoxic induction of hypoxia-inducible factor-1α by inhibition of synthesis and not enhanced degradation. J Neurosci Res 2013; 91:1066-75. [PMID: 23456821 DOI: 10.1002/jnr.23204] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 12/04/2012] [Accepted: 12/22/2012] [Indexed: 01/08/2023]
Abstract
Hypoxia-inducible factor (HIF) mediates a broad, conserved adaptive response to hypoxia, and the HIF pathway is a potential therapeutic target in cerebral ischemia. This study investigated the mechanism by which in vitro ischemia (oxygen-glucose deprivation; OGD) affects canonical hypoxic HIF-1α stabilization. We validated the use of a reporter containing the oxygen-dependent degradation domain of HIF-1α fused to firefly luciferase (ODD-luc) to monitor quantitatively distinct biochemical events leading to hypoxic HIF-1α expression or stabilization in a human neuroblastoma cell line (SH-SY5Y). When OGD was imposed following a 2-hr hypoxic stabilization of ODD-luc, the levels of the reporter were reduced, consistent with prior models proposing that OGD enhances HIF prolylhydroxylase (PHD) activity. Surprisingly, PHD inhibitors and proteasome inhibitors do not stabilize ODD-luc in OGD. Furthermore, OGD does not affect the half-life of ODD-luc protein following hypoxia, suggesting that OGD abrogates hypoxic HIF-1α induction by reducing HIF-1α synthesis rather than by enhancing its degradation. We observed ATP depletion under OGD vs. hypoxia and propose that ATP depletion enhances translational suppression, overcoming the selective synthesis of HIF concurrent with global decreases in protein synthesis in hypoxia. Taken together, these findings biochemically characterize a practical reporter for monitoring HIF-1α levels and support a novel model for HIF regulation in an in vitro model of human ischemia.
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Affiliation(s)
- Saravanan S Karuppagounder
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, New York, USA
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12
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Ulm EA, Sleiman SF, Chamberlin HM. Developmental functions for the Caenorhabditis elegans Sp protein SPTF-3. Mech Dev 2011; 128:428-41. [PMID: 21884786 DOI: 10.1016/j.mod.2011.08.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 08/12/2011] [Accepted: 08/14/2011] [Indexed: 10/17/2022]
Abstract
Sp factors are important for animal development and the transcriptional regulation of a wide variety of genes. How they influence the developmental decisions of individual cells within the organism, however, is poorly understood. To better understand the developmental functions for Sp transcription factors, we have characterized the functions of Caenorhabditis elegans SPTF-3 using RNAi knockdown and a non-null, hypomorphic mutant allele. We find that disruption of sptf-3 confers a variety of developmental defects, including defects in development of the egg-laying system, oocyte production, and embryonic morphogenesis. sptf-3 mutants exhibit defects in vulval lineage polarity, a phenotype previously only observed in mutants defective in Wnt signaling. We show that the embryonic function of sptf-3 is dependent on germline activity, arguing that the gene has an important maternal contribution to embryonic development. An evaluation of reporter gene expression suggests that SPTF-3 exhibits specificity, in that it can influence the expression of a given gene in some cells but not others, and that SPTF-3 participates in the maintenance of gene expression states in differentiated cells. We propose SPTF-3 provides a good model to study the in vivo functions for Sp transcription factors during animal development.
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Affiliation(s)
- Elizabeth A Ulm
- Department of Molecular Genetics, Ohio State University, 484 W.12th Ave., Columbus, OH 43210, USA.
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13
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McConoughey SJ, Basso M, Niatsetskaya ZV, Sleiman SF, Smirnova NA, Langley BC, Mahishi L, Cooper AJL, Antonyak MA, Cerione RA, Li B, Starkov A, Chaturvedi RK, Beal MF, Coppola G, Geschwind DH, Ryu H, Xia L, Iismaa SE, Pallos J, Pasternack R, Hils M, Fan J, Raymond LA, Marsh JL, Thompson LM, Ratan RR. Inhibition of transglutaminase 2 mitigates transcriptional dysregulation in models of Huntington disease. EMBO Mol Med 2011; 2:349-70. [PMID: 20665636 PMCID: PMC3068019 DOI: 10.1002/emmm.201000084] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Caused by a polyglutamine expansion in the huntingtin protein, Huntington's disease leads to striatal degeneration via the transcriptional dysregulation of a number of genes, including those involved in mitochondrial biogenesis. Here we show that transglutaminase 2, which is upregulated in HD, exacerbates transcriptional dysregulation by acting as a selective corepressor of nuclear genes; transglutaminase 2 interacts directly with histone H3 in the nucleus. In a cellular model of HD, transglutaminase inhibition de-repressed two established regulators of mitochondrial function, PGC-1α and cytochrome c and reversed susceptibility of human HD cells to the mitochondrial toxin, 3-nitroproprionic acid; however, protection mediated by transglutaminase inhibition was not associated with improved mitochondrial bioenergetics. A gene microarray analysis indicated that transglutaminase inhibition normalized expression of not only mitochondrial genes but also 40% of genes that are dysregulated in HD striatal neurons, including chaperone and histone genes. Moreover, transglutaminase inhibition attenuated degeneration in a Drosophila model of HD and protected mouse HD striatal neurons from excitotoxicity. Altogether these findings demonstrate that selective TG inhibition broadly corrects transcriptional dysregulation in HD and defines a novel HDAC-independent epigenetic strategy for treating neurodegeneration.
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14
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Sleiman SF, Basso M, Mahishi L, Kozikowski AP, Donohoe ME, Langley B, Ratan RR. Putting the 'HAT' back on survival signalling: the promises and challenges of HDAC inhibition in the treatment of neurological conditions. Expert Opin Investig Drugs 2010; 18:573-84. [PMID: 19388875 DOI: 10.1517/13543780902810345] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Decreased histone acetyltransferase activity and transcriptional dysfunction have been implicated in almost all neurodegenerative conditions. Increasing net histone acetyltransferase activity through inhibition of the histone deacetylases (HDACs) has been shown to be an effective strategy to delay or halt progression of neurological disease in cellular and rodent models. These findings have provided firm rationale for Phase I and Phase II clinical trials of HDAC inhibitors in Huntington's disease, spinal muscular atrophy, and Freidreich's ataxia. In this review, we discuss the current findings and promise of HDAC inhibition as a strategy for treating neurological disorders. Despite the fact that HDAC inhibitors are in an advanced stage of development, we suggest other approaches to modulating HDAC function that may be less toxic and more efficacious than the canonical agents developed so far.
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Affiliation(s)
- Sama F Sleiman
- Burke Medical Research Institute, 785 Mamaroneck Avenue, White Plains, 10605 NY, USA.
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15
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Sun H, Nelms BL, Sleiman SF, Chamberlin HM, Hanna-Rose W. Modulation of Caenorhabditis elegans transcription factor activity by HIM-8 and the related Zinc-Finger ZIM proteins. Genetics 2007; 177:1221-6. [PMID: 17720937 PMCID: PMC2034626 DOI: 10.1534/genetics.107.070847] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The previously reported negative regulatory activity of HIM-8 on the Sox protein EGL-13 is shared by the HIM-8-related ZIM proteins. Furthermore, mutation of HIM-8 can modulate the effects of substitution mutations in the DNA-binding domains of at least four other transcription factors, suggesting broad regulatory activity by HIM-8.
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Affiliation(s)
- Hongliu Sun
- Intercollege Graduate Degree Program in Genetics, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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16
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Zhang G, Sleiman SF, Tseng RJ, Rajakumar V, Wang X, Chamberlin HM. Alteration of the DNA binding domain disrupts distinct functions of the C. elegans Pax protein EGL-38. Mech Dev 2005; 122:887-99. [PMID: 15923112 DOI: 10.1016/j.mod.2005.04.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2004] [Revised: 04/13/2005] [Accepted: 04/18/2005] [Indexed: 11/26/2022]
Abstract
The paired-domain-containing Pax transcription factors play an important role in the development of a range of organ, tissue and cell types. Although DNA binding elements and target genes for Pax proteins have been identified, how these proteins identify appropriate DNA elements and regulate different genes in different cellular contexts is not well understood. To investigate the relationship between Pax proteins and their targets, we have studied the in vivo and in vitro properties associated with wild-type and different mutant variants of the Caenorhabditis elegans Pax protein EGL-38. Here, we characterize the properties of four mutations that result in an amino acid substitution in the DNA binding domain of EGL-38. We find that animals bearing the different mutant alleles exhibit tissue-preferential defects in egl-38 function. The mutant proteins are also altered in their activity in an ectopic expression assay and in their in vitro DNA binding properties. Using in vitro selection, we have identified binding sites for EGL-38. However, we show that selected sites function poorly in vivo as EGL-38 response elements, indicating that sequence features in addition to DNA binding determine the efficacy of Pax response elements. The distinction between DNA binding and activity is consistent with the model that other factors commonly play a role in mediating Pax protein target site selection and function in vivo.
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Affiliation(s)
- Guojuan Zhang
- Department of Molecular Genetics, Ohio State University, 938 Biological Sciences Building, 484 West 12th Avenue, Columbus, OH 43210, USA
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