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Song Y, Cao H, Zuo C, Gu Z, Huang Y, Miao J, Fu Y, Guo Y, Jiang Y, Wang F. Mitochondrial dysfunction: A fatal blow in depression. Biomed Pharmacother 2023; 167:115652. [PMID: 37801903 DOI: 10.1016/j.biopha.2023.115652] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 10/01/2023] [Accepted: 10/03/2023] [Indexed: 10/08/2023] Open
Abstract
Mitochondria maintain the normal physiological function of nerve cells by producing sufficient cellular energy and performing crucial roles in maintaining the metabolic balance through intracellular Ca2+ homeostasis, oxidative stress, and axonal development. Depression is a prevalent psychiatric disorder with an unclear pathophysiology. Damage to the hippocampal neurons is a key component of the plasticity regulation of synapses and plays a critical role in the mechanism of depression. There is evidence suggesting that mitochondrial dysfunction is associated with synaptic impairment. The maintenance of mitochondrial homeostasis includes quantitative maintenance and quality control of mitochondria. Mitochondrial biogenesis produces new and healthy mitochondria, and mitochondrial dynamics cooperates with mitophagy to remove damaged mitochondria. These processes maintain mitochondrial population stability and exert neuroprotective effects against early depression. In contrast, mitochondrial dysfunction is observed in various brain regions of patients with major depressive disorders. The accumulation of defective mitochondria accelerates cellular nerve dysfunction. In addition, impaired mitochondria aggravate alterations in the brain microenvironment, promoting neuroinflammation and energy depletion, thereby exacerbating the development of depression. This review summarizes the influence of mitochondrial dysfunction and the underlying molecular pathways on the pathogenesis of depression. Additionally, we discuss the maintenance of mitochondrial homeostasis as a potential therapeutic strategy for depression.
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Affiliation(s)
- Yu Song
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan 430030, Hubei, China
| | - Huan Cao
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan 430030, Hubei, China
| | - Chengchao Zuo
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan 430030, Hubei, China
| | - Zhongya Gu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan 430030, Hubei, China
| | - Yaqi Huang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan 430030, Hubei, China
| | - Jinfeng Miao
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan 430030, Hubei, China
| | - Yufeng Fu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan 430030, Hubei, China
| | - Yu Guo
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan 430030, Hubei, China
| | - Yongsheng Jiang
- Cancer Center of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan, 430030 Hubei, China.
| | - Furong Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan 430030, Hubei, China; Key Laboratory of Vascular Aging (HUST), Ministry of Education, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan, 430030 Hubei, China.
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Jeanneteau F. Stress and the risk of Alzheimer dementia: Can deconstructed engrams be rebuilt? J Neuroendocrinol 2023; 35:e13235. [PMID: 36775895 DOI: 10.1111/jne.13235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/20/2023] [Accepted: 01/21/2023] [Indexed: 01/26/2023]
Abstract
The exact neuropathological mechanism by which the dementia process unfolds is under intense scrutiny. The disease affects about 38 million people worldwide, 70% of which are clinically diagnosed with Alzheimer's disease (AD). If the destruction of synapses essential for learning, planning and decision-making is part of the problem, must the restoration of previously lost synapses be part of the solution? It is plausible that neuronal capacity to restitute information corresponds with the adaptive capacity of its connectivity reserve. A challenge will be to promote the functional connectivity that can compensate for the lost one. This will require better clarification of the remodeling of functional connectivity during the progression of AD dementia and its reversal upon experimental treatment. A major difficulty is to promote the neural pathways that are atrophied in AD dementia while suppressing others that are bolstered. Therapeutic strategies should aim at scaling functional connectivity to a just balance between the atrophic and hypertrophic systems. However, the exact factors that can help reach this objective are still unclear. Similarities between the effects of chronic stress and some neuropathological mechanisms underlying AD dementia support the idea that common components deserve prime attention as therapeutic targets.
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Affiliation(s)
- Freddy Jeanneteau
- Institut de génomique fonctionnelle, Université de Montpellier, INSERM, CNRS, Montpellier, France
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3
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Sui H, Zhu L, Zhan L, Bi T, Zhang B. ZiBuPiYin recipe ameliorates diabetes-associated cognitive decline by improving neuronal mitochondrial function in chronic psychologically stressed zucker diabetic fatty rats. JOURNAL OF ETHNOPHARMACOLOGY 2023; 302:115947. [PMID: 36403740 DOI: 10.1016/j.jep.2022.115947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 10/13/2022] [Accepted: 11/13/2022] [Indexed: 06/16/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Zibu Piyin Recipe (ZBPYR) is a traditional Chinese medicine compound composed of 12 kinds of Chinese herbal medicines including red ginseng and yam. Long-term basic and clinical applications have proved that ZBPYR can prevent and treat cognitive dysfunction. Previous studies showed that chronic psychological stress can increase the risk of type 2 diabetes mellitus (T2DM), and lead to cognitive decline. Mitochondrial dysfunction plays a key role in chronic psychological stress-induced diabetes mellitus. While the mechanism of mitochondrial dysfunction and insulin resistance in diabetes-associated cognitive decline (DACD) is unclear. AIM OF THE STUDY Our previous research found that a ZiBuPiYin recipe (ZBPYR) has significant pharmacological effects against DACD. The present study investigated changes in mitochondrial dysfunction in the brain and the mechanism of insulin resistance and mitochondrial damage to explore the relationship between neuronal mitochondrial dysfunction and insulin resistance in chronic psychologically stressed DACD rats. MATERIALS AND METHODS Zucker diabetic fatty (ZDF) rats with spontaneous T2DM and rats with diabetic cognitive impairment that was induced by chronic psychological stress were used in in vivo experiments. PC12 cells that were damaged by rotenone were used for the in vitro experiment. RESULTS The findings indicated that the number of mitochondria decreased, morphology and membrane potential were damaged, and reactive oxygen species increased in the cortex and hippocampus in psychologically stressed DACD rats. Protein kinase Cβ2 (PKCβ2) activation and insulin resistance were markedly induced by chronic psychological stress, together with decreases in peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) and mitochondrial fusion protein 2 (Mfn2). Furthermore, ZBPYR exerted protective effects both in in vivo and in vitro. CONCLUSION Mitochondrial damage and insulin resistance were observed in the brain in chronic psychologically stressed DACD rats. The ZBPYR significantly improved brain mitochondrial damage and insulin resistance in chronic psychologically stressed DACD rats. These results provide novel insights for the development of ZBPYR as a traditional Chinese medicine for the treatment of chronic psychological stress and DACD.
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Affiliation(s)
- Hua Sui
- Institute of Integrative Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China.
| | - Lianlian Zhu
- Liaoning University of Traditional Chinese Medicine, Shenyang, 110847, Liaoning, China.
| | - Libin Zhan
- Liaoning University of Traditional Chinese Medicine, Shenyang, 110847, Liaoning, China.
| | - Tingting Bi
- School of Traditional Chinese Medicine & School of Integrated Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, 210023, Jiangsu, China.
| | - Boyu Zhang
- Institute of Integrative Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China.
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Fries GR, Saldana VA, Finnstein J, Rein T. Molecular pathways of major depressive disorder converge on the synapse. Mol Psychiatry 2023; 28:284-297. [PMID: 36203007 PMCID: PMC9540059 DOI: 10.1038/s41380-022-01806-1] [Citation(s) in RCA: 104] [Impact Index Per Article: 104.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 09/07/2022] [Accepted: 09/14/2022] [Indexed: 01/07/2023]
Abstract
Major depressive disorder (MDD) is a psychiatric disease of still poorly understood molecular etiology. Extensive studies at different molecular levels point to a high complexity of numerous interrelated pathways as the underpinnings of depression. Major systems under consideration include monoamines, stress, neurotrophins and neurogenesis, excitatory and inhibitory neurotransmission, mitochondrial dysfunction, (epi)genetics, inflammation, the opioid system, myelination, and the gut-brain axis, among others. This review aims at illustrating how these multiple signaling pathways and systems may interact to provide a more comprehensive view of MDD's neurobiology. In particular, considering the pattern of synaptic activity as the closest physical representation of mood, emotion, and conscience we can conceptualize, each pathway or molecular system will be scrutinized for links to synaptic neurotransmission. Models of the neurobiology of MDD will be discussed as well as future actions to improve the understanding of the disease and treatment options.
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Affiliation(s)
- Gabriel R. Fries
- grid.267308.80000 0000 9206 2401Translational Psychiatry Program, Faillace Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, 1941 East Rd, Houston, TX 77054 USA ,grid.240145.60000 0001 2291 4776Neuroscience Graduate Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, 6767 Bertner Ave, Houston, TX 77030 USA
| | - Valeria A. Saldana
- grid.262285.90000 0000 8800 2297Frank H. Netter MD School of Medicine at Quinnipiac University, 370 Bassett Road, North Haven, CT 06473 USA
| | - Johannes Finnstein
- grid.419548.50000 0000 9497 5095Department of Translational Research in Psychiatry, Project Group Molecular Pathways of Depression, Max Planck Institute of Psychiatry, Kraepelinstr. 10, 80804 Munich, Germany
| | - Theo Rein
- Department of Translational Research in Psychiatry, Project Group Molecular Pathways of Depression, Max Planck Institute of Psychiatry, Kraepelinstr. 10, 80804, Munich, Germany.
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Ahmad F, Ramamorthy S, Areeshi MY, Ashraf GM, Haque S. Isolated Mitochondrial Preparations and In organello Assays: A Powerful and Relevant Ex vivo Tool for Assessment of Brain (Patho)physiology. Curr Neuropharmacol 2023; 21:1433-1449. [PMID: 36872352 PMCID: PMC10324330 DOI: 10.2174/1570159x21666230303123555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 10/30/2022] [Accepted: 12/29/2022] [Indexed: 03/07/2023] Open
Abstract
Mitochondria regulate multiple aspects of neuronal development, physiology, plasticity, and pathology through their regulatory roles in bioenergetic, calcium, redox, and cell survival/death signalling. While several reviews have addressed these different aspects, a comprehensive discussion focussing on the relevance of isolated brain mitochondria and their utilities in neuroscience research has been lacking. This is relevant because the employment of isolated mitochondria rather than their in situ functional evaluation, offers definitive evidence of organelle-specificity, negating the interference from extra mitochondrial cellular factors/signals. This mini-review was designed primarily to explore the commonly employed in organello analytical assays for the assessment of mitochondrial physiology and its dysfunction, with a particular focus on neuroscience research. The authors briefly discuss the methodologies for biochemical isolation of mitochondria, their quality assessment, and cryopreservation. Further, the review attempts to accumulate the key biochemical protocols for in organello assessment of a multitude of mitochondrial functions critical for neurophysiology, including assays for bioenergetic activity, calcium and redox homeostasis, and mitochondrial protein translation. The purpose of this review is not to examine each and every method or study related to the functional assessment of isolated brain mitochondria, but rather to assemble the commonly used protocols of in organello mitochondrial research in a single publication. The hope is that this review will provide a suitable platform aiding neuroscientists to choose and apply the required protocols and tools to address their particular mechanistic, diagnostic, or therapeutic question dealing within the confines of the research area of mitochondrial patho-physiology in the neuronal perspective.
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Affiliation(s)
- Faraz Ahmad
- Department of Biotechnology, School of Bio Sciences and Technology (SBST), Vellore Institute of Technology, Vellore, 632014, India
| | - Siva Ramamorthy
- Department of Biotechnology, School of Bio Sciences and Technology (SBST), Vellore Institute of Technology, Vellore, 632014, India
| | - Mohammed Y. Areeshi
- Medical Laboratory Technology Department, College of Applied Medical Sciences, Jazan University, Jazan, 45142, Saudi Arabia
- Research and Scientific Studies Unit, College of Nursing and Allied Health Sciences, Jazan University, Jazan, 45142, Saudi Arabia
| | - Ghulam Md. Ashraf
- Department of Medical Laboratory Sciences, College of Health Sciences, and Sharjah Institute for Medical Research, University of Sharjah, Sharjah, 27272, United Arab Emirates
| | - Shafiul Haque
- Research and Scientific Studies Unit, College of Nursing and Allied Health Sciences, Jazan University, Jazan, 45142, Saudi Arabia
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Beirut, Lebanon
- Centre of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman, United Arab Emirates
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Öğütlü H, Kaşak M, Tabur ST. Mitochondrial Dysfunction in Attention Deficit Hyperactivity Disorder. Eurasian J Med 2022; 54:187-195. [PMID: 36655466 PMCID: PMC11163340 DOI: 10.5152/eurasianjmed.2022.22187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 11/14/2022] [Indexed: 01/19/2023] Open
Abstract
Attention deficit hyperactivity disorder is a neurodevelopmental disorder with primary symptoms of inattention, hyperactivity, and impulsivity, beginning in early childhood. Attention deficit hyperactivity disorder has a complex etiology based on neurobiological foundations, involving genetic, environmental, and biological factors in the early development process. The etiology of attention deficit hyperactivity disorder has not been completely clarified yet, but it has been suggested that increased oxidative stress is one of the possible common etiologies in attention deficit hyperactivity disorder. Oxidative stress can cause cellular damage, DNA repair system malfunction, and mitochondrial dysfunction. Mitochondrial dysfunction is thought to be a susceptibility factor in the development of psychiatric diseases. This article aims to review the research conducted to evaluate the possible relationship between attention deficit hyperactivity disorder and mitochondrial dysfunction and systematically examine the data obtained from these studies. Although studies considering the relationship between attention deficit hyperactivity disorder and mitochondrial dysfunction are less than those of autism spectrum disorder, schizophrenia, and mood disorders, studies on attention deficit hyperactivity disorder are increasing. A compensating system against mitochondrial dysfunction caused by hereditary and environmental factors may be generated by an increase in mitochondrial DNA copy number. Mitochondrial DNA copies may decrease with the reduction of attention deficit hyperactivity disorder severity and attention deficit in patients receiving treatment and may positively affect mitochondrial functions. The literature data of this review show that mitochondrial dysfunction could be a crucial factor in the pathophysiology of attention deficit hyperactivity disorder. Understanding mitochondrial contributions in the pathogenesis of attention deficit hyperactivity disorder may result in new diagnostic tools and the development of new therapeutic strategies for attention deficit hyperactivity disorder treatment.
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Affiliation(s)
- Hakan Öğütlü
- Department of Child and Adolescent Psychiatry, Cognitive Behavioral Psychotherapies Association, Ankara, Turkey
| | - Meryem Kaşak
- Department of Child and Adolescent Psychiatry, Ankara City Hospital, Ankara, Turkey
| | - Selin Tutku Tabur
- Department of Psychology, Hasan Kalyoncu University Faculty of Economics, Administrative and Social Sciences, Turkey
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Agapouda A, Grimm A, Lejri I, Eckert A. Rhodiola Rosea Extract Counteracts Stress in an Adaptogenic Response Curve Manner via Elimination of ROS and Induction of Neurite Outgrowth. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:5647599. [PMID: 35602107 PMCID: PMC9122715 DOI: 10.1155/2022/5647599] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 04/11/2022] [Accepted: 04/26/2022] [Indexed: 11/22/2022]
Abstract
Background Sustained stress with the overproduction of corticosteroids has been shown to increase reactive oxygen species (ROS) leading to an oxidative stress state. Mitochondria are the main generators of ROS and are directly and detrimentally affected by their overproduction. Neurons depend almost solely on ATP produced by mitochondria in order to satisfy their energy needs and to form synapses, while stress has been proven to alter synaptic plasticity. Emerging evidence underpins that Rhodiola rosea, an adaptogenic plant rich in polyphenols, exerts antioxidant, antistress, and neuroprotective effects. Methods In this study, the effect of Rhodiola rosea extract (RRE) WS®1375 on neuronal ROS regulation, bioenergetics, and neurite outgrowth, as well as its potential modulatory effect on the brain derived neurotrophic factor (BDNF) pathway, was evaluated in the human neuroblastoma SH-SY5Y and the murine hippocampal HT22 cell lines. Stress was induced using the corticosteroid dexamethasone. Results RRE increased bioenergetics as well as cell viability and scavenged ROS with a similar efficacy in both cells lines and counteracted the respective corticosteroid-induced dysregulation. The effect of RRE, both under dexamethasone-stress and under normal conditions, resulted in biphasic U-shape and inverted U-shape dose response curves, a characteristic feature of adaptogenic plant extracts. Additionally, RRE treatment promoted neurite outgrowth and induced an increase in BDNF levels. Conclusion These findings indicate that RRE may constitute a candidate for the prevention of stress-induced pathophysiological processes as well as oxidative stress. Therefore, it could be employed against stress-associated mental disorders potentially leading to the development of a condition-specific supplementation.
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Affiliation(s)
- Anastasia Agapouda
- University of Basel, Transfaculty Research Platform, Molecular and Cognitive Neuroscience, Neurobiology Lab for Brain Aging and Mental Health, Basel, Switzerland
- Psychiatric University Clinics, Basel, Switzerland
| | - Amandine Grimm
- University of Basel, Transfaculty Research Platform, Molecular and Cognitive Neuroscience, Neurobiology Lab for Brain Aging and Mental Health, Basel, Switzerland
- Psychiatric University Clinics, Basel, Switzerland
| | - Imane Lejri
- University of Basel, Transfaculty Research Platform, Molecular and Cognitive Neuroscience, Neurobiology Lab for Brain Aging and Mental Health, Basel, Switzerland
- Psychiatric University Clinics, Basel, Switzerland
| | - Anne Eckert
- University of Basel, Transfaculty Research Platform, Molecular and Cognitive Neuroscience, Neurobiology Lab for Brain Aging and Mental Health, Basel, Switzerland
- Psychiatric University Clinics, Basel, Switzerland
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Shaw GA. Mitochondria as the target for disease related hormonal dysregulation. Brain Behav Immun Health 2021; 18:100350. [PMID: 34746877 PMCID: PMC8554460 DOI: 10.1016/j.bbih.2021.100350] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 09/12/2021] [Accepted: 09/17/2021] [Indexed: 12/13/2022] Open
Abstract
Mitochondria play an important role in the synthesis of steroid hormones, including the sex hormone estrogen. Sex-specific regulation of these hormones is important for phenotypic development and downstream, sex-specific activational effects in both brain and behavior. First, mitochondrial contribution to the synthesis of estrogen, followed by a discussion of the signaling interactions between estrogen and the mitochondria will be reviewed. Next, disorders with an established sex difference related to aging, mood, and cognition will be examined. Finally, review of mitochondria as a biomarker of disease and data supporting efforts in targeting mitochondria as a therapeutic target for the amelioration of these disorders will be discussed. Taken together, this review aims to assess the influence of E2 on mitochondrial function within the brain via exploration of E2-ER interactions within neural mitochondria and how they may act to influence the development and presentation of neurodegenerative and neurocognitive diseases with known sex differences.
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Affiliation(s)
- Gladys A. Shaw
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, USA
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Spadini S, Racchetti G, Adiletta A, Lamanna J, Moro AS, Ferro M, Zimarino V, Malgaroli A. A novel integrated approach to estimate the mitochondrial content of neuronal cells and brain tissues. J Neurosci Methods 2021; 363:109351. [PMID: 34481832 DOI: 10.1016/j.jneumeth.2021.109351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 07/28/2021] [Accepted: 08/31/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Mitochondria and their dynamics fuel most cellular processes both in physiological and pathological conditions. In the central nervous system, mitochondria sustain synaptic transmission and plasticity via multiple mechanisms which include their redistribution and/or expansion to higher energy demanding sites, sustaining activity changes and promoting morphological circuit adaptations. NEW METHOD To be able to evaluate changes in mitochondrial number and protein phenotype, we propose a novel methodological approach where the simultaneous analysis of both mitochondrial DNA and protein content is performed on each individual microsample, avoiding non-homogeneous loss of material. RESULTS We validated this method on neuronal-like cells and tissue samples and obtained estimates for the mitochondrial/genomic DNA ratio as well as for the abundance of protein counterparts. When the mitochondrial content per cell was evaluated in different brain areas, our results matched the known regional variation in aerobic-anaerobic metabolism. When long-term potentiation (LTP) was induced on hippocampal neurons, we detected increases in the abundance of mitochondria that correlated with the degree of synaptic enhancement. CONCLUSIONS Our approach can be effectively used to study the mitochondrial content andits changes in different brain cells and tissues.
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Affiliation(s)
- Sara Spadini
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, Via Olgettina 58, Milan 20132, Italy; Faculty of Psychology, Vita-Salute San Raffaele University, Milan, Italy
| | - Gabriella Racchetti
- Division of Neuroscience, Scientific Institute Ospedale San Raffaele, Milan, Italy
| | - Alice Adiletta
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, Via Olgettina 58, Milan 20132, Italy; Center for Mind/Brain Sciences (CIMeC), University of Trento, Rovereto, Italy
| | - Jacopo Lamanna
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, Via Olgettina 58, Milan 20132, Italy; Faculty of Psychology, Vita-Salute San Raffaele University, Milan, Italy
| | - Andrea Stefano Moro
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, Via Olgettina 58, Milan 20132, Italy; Department of Psychology, Sigmund Freud University, Milan, Italy
| | - Mattia Ferro
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, Via Olgettina 58, Milan 20132, Italy; Department of Psychology, Sigmund Freud University, Milan, Italy
| | - Vincenzo Zimarino
- Division of Neuroscience, Scientific Institute Ospedale San Raffaele, Milan, Italy
| | - Antonio Malgaroli
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, Via Olgettina 58, Milan 20132, Italy; Faculty of Psychology, Vita-Salute San Raffaele University, Milan, Italy.
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Dual imaging of dendritic spines and mitochondria in vivo reveals hotspots of plasticity and metabolic adaptation to stress. Neurobiol Stress 2021; 15:100402. [PMID: 34611532 PMCID: PMC8477201 DOI: 10.1016/j.ynstr.2021.100402] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 09/16/2021] [Accepted: 09/17/2021] [Indexed: 01/09/2023] Open
Abstract
Metabolic adaptation is a critical feature of synaptic plasticity. Indeed, synaptic plasticity requires the utilization and resupply of metabolites, in particular when the turnover is high and fast such as in stress conditions. What accounts for the localized energy burden of the post-synaptic compartment to the build up of chronic stress is currently not understood. We used in vivo microscopy of genetically encoded fluorescent probes to track changes of mitochondria, dendritic spines, ATP and H2O2 levels in pyramidal neurons of cortex before and after chronic unpredictable mild stress. Data revealed hotspots of postsynaptic mitochondria and dendritic spine turnover. Pharmacogenetic approach to force expression of the metabolic stress gene NR4A1 caused the fragmentation of postsynaptic mitochondria and loss of proximal dendritic spine clusters, whereas a dominant-negative mutant counteracted the effect of chronic stress. When fragmented, dendritic mitochondria produced lesser ATP at resting state and more on acute demand. This corresponded with significant production of mitochondrial H2O2 oxidative species in the dendritic compartment. Together, data indicate that pyramidal neurons adjust proximal dendritic spine turnover and mitochondria functions in keeping with synaptic demands. Addition of dendritic spine clusters match with more proximal mitochondria coverage. Loss of dendritic spine clusters match with less proximal mitochondria coverage. Dendrites alter spine dynamics, ATP and H202 production in keeping with excitation. In excess, the transcription factor NR4A1 promotes cross-clustering losses. Blocking NR4A1 prevents net cross-clustering losses mediated by chronic stress.
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Costa-Rodrigues C, Couceiro J, Moreno E. Cell competition from development to neurodegeneration. Dis Model Mech 2021; 14:269331. [PMID: 34190316 PMCID: PMC8277968 DOI: 10.1242/dmm.048926] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Cell competition is a process by which suboptimal cells are eliminated to the benefit of cells with higher fitness. It is a surveillance mechanism that senses differences in the fitness status by several modes, such as expression of fitness fingerprints, survival factor uptake rate and resistance to mechanical stress. Fitness fingerprints-mediated cell competition recognizes isoforms of the transmembrane protein Flower, and translates the relative fitness of cells into distinct fates through the Flower code. Impairments in cell competition potentiate the development of diseases like cancer and ageing-related pathologies. In cancer, malignant cells acquire a supercompetitor behaviour, killing the neighbouring cells and overtaking the tissue, thus avoiding elimination. Neurodegenerative disorders affect millions of people and are characterized by cognitive decline and locomotor deficits. Alzheimer's disease is the most common form of dementia, and one of the largely studied diseases. However, the cellular processes taking place remain unclear. Drosophila melanogaster is an emerging neurodegeneration model due to its versatility as a tool for genetic studies. Research in a Drosophila Alzheimer's disease model detected fitness markers in the suboptimal and hyperactive neurons, thus establishing a link between cell competition and Alzheimer's disease. In this Review, we overview cell competition and the new insights related to neurodegenerative disorders, and discuss how research in the field might contribute to the development of new therapeutic targets for these diseases.
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Affiliation(s)
| | - Joana Couceiro
- Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal
| | - Eduardo Moreno
- Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal
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Asslih S, Damri O, Agam G. Neuroinflammation as a Common Denominator of Complex Diseases (Cancer, Diabetes Type 2, and Neuropsychiatric Disorders). Int J Mol Sci 2021; 22:ijms22116138. [PMID: 34200240 PMCID: PMC8201050 DOI: 10.3390/ijms22116138] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/31/2021] [Accepted: 05/31/2021] [Indexed: 12/15/2022] Open
Abstract
The term neuroinflammation refers to inflammation of the nervous tissue, in general, and in the central nervous system (CNS), in particular. It is a driver of neurotoxicity, it is detrimental, and implies that glial cell activation happens prior to neuronal degeneration and, possibly, even causes it. The inflammation-like glial responses may be initiated in response to a variety of cues such as infection, traumatic brain injury, toxic metabolites, or autoimmunity. The inflammatory response of activated microglia engages the immune system and initiates tissue repair. Through translational research the role played by neuroinflammation has been acknowledged in different disease entities. Intriguingly, these entities include both those directly related to the CNS (commonly designated neuropsychiatric disorders) and those not directly related to the CNS (e.g., cancer and diabetes type 2). Interestingly, all the above-mentioned entities belong to the same group of "complex disorders". This review aims to summarize cumulated data supporting the hypothesis that neuroinflammation is a common denominator of a wide variety of complex diseases. We will concentrate on cancer, type 2 diabetes (T2DM), and neuropsychiatric disorders (focusing on mood disorders).
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Mitochondrial Glucocorticoid Receptors and Their Actions. Int J Mol Sci 2021; 22:ijms22116054. [PMID: 34205227 PMCID: PMC8200016 DOI: 10.3390/ijms22116054] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 05/27/2021] [Accepted: 05/29/2021] [Indexed: 12/18/2022] Open
Abstract
Mitochondria are membrane organelles present in almost all eukaryotic cells. In addition to their well-known role in energy production, mitochondria regulate central cellular processes, including calcium homeostasis, Reactive Oxygen Species (ROS) generation, cell death, thermogenesis, and biosynthesis of lipids, nucleic acids, and steroid hormones. Glucocorticoids (GCs) regulate the mitochondrially encoded oxidative phosphorylation gene expression and mitochondrial energy metabolism. The identification of Glucocorticoid Response Elements (GREs) in mitochondrial sequences and the detection of Glucocorticoid Receptor (GR) in mitochondria of different cell types gave support to hypothesis that mitochondrial GR directly regulates mitochondrial gene expression. Numerous studies have revealed changes in mitochondrial gene expression alongside with GR import/export in mitochondria, confirming the direct effects of GCs on mitochondrial genome. Further evidence has made clear that mitochondrial GR is involved in mitochondrial function and apoptosis-mediated processes, through interacting or altering the distribution of Bcl2 family members. Even though its exact translocation mechanisms remain unknown, data have shown that GR chaperones (Hsp70/90, Bag-1, FKBP51), the anti-apoptotic protein Bcl-2, the HDAC6- mediated deacetylation and the outer mitochondrial translocation complexes (Tom complexes) co-ordinate GR mitochondrial trafficking. A role of mitochondrial GR in stress and depression as well as in lung and hepatic inflammation has also been demonstrated.
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Gonzalez-Lozano MA, Wortel J, van der Loo RJ, van Weering JRT, Smit AB, Li KW. Reduced mGluR5 Activity Modulates Mitochondrial Function. Cells 2021; 10:cells10061375. [PMID: 34199502 PMCID: PMC8228325 DOI: 10.3390/cells10061375] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 05/23/2021] [Accepted: 05/31/2021] [Indexed: 11/30/2022] Open
Abstract
The metabotropic glutamate receptor 5 (mGluR5) is an essential modulator of synaptic plasticity, learning and memory; whereas in pathological conditions, it is an acknowledged therapeutic target that has been implicated in multiple brain disorders. Despite robust pre-clinical data, mGluR5 antagonists failed in several clinical trials, highlighting the need for a better understanding of the mechanisms underlying mGluR5 function. In this study, we dissected the molecular synaptic modulation mediated by mGluR5 using genetic and pharmacological mouse models to chronically and acutely reduce mGluR5 activity. We found that next to dysregulation of synaptic proteins, the major regulation in protein expression in both models concerned specific processes in mitochondria, such as oxidative phosphorylation. Second, we observed morphological alterations in shape and area of specifically postsynaptic mitochondria in mGluR5 KO synapses using electron microscopy. Third, computational and biochemical assays suggested an increase of mitochondrial function in neurons, with increased level of NADP/H and oxidative damage in mGluR5 KO. Altogether, our observations provide diverse lines of evidence of the modulation of synaptic mitochondrial function by mGluR5. This connection suggests a role for mGluR5 as a mediator between synaptic activity and mitochondrial function, a finding which might be relevant for the improvement of the clinical potential of mGluR5.
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Affiliation(s)
- Miguel A. Gonzalez-Lozano
- Center for Neurogenomics and Cognitive Research, Department of Molecular and Cellular Neurobiology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (R.J.v.d.L.); (A.B.S.)
- Correspondence: (M.A.G.-L.); (K.W.L.)
| | - Joke Wortel
- Center for Neurogenomics and Cognitive Research, Department of Functional Genomics, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (J.W.); (J.R.T.v.W.)
| | - Rolinka J. van der Loo
- Center for Neurogenomics and Cognitive Research, Department of Molecular and Cellular Neurobiology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (R.J.v.d.L.); (A.B.S.)
| | - Jan R. T. van Weering
- Center for Neurogenomics and Cognitive Research, Department of Functional Genomics, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (J.W.); (J.R.T.v.W.)
- Center for Neurogenomics and Cognitive Research, Department of Clinical Genetics, Amsterdam Neuroscience, Amsterdam UMC location VUmc, 1081 Amsterdam, The Netherlands
| | - August B. Smit
- Center for Neurogenomics and Cognitive Research, Department of Molecular and Cellular Neurobiology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (R.J.v.d.L.); (A.B.S.)
| | - Ka Wan Li
- Center for Neurogenomics and Cognitive Research, Department of Molecular and Cellular Neurobiology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (R.J.v.d.L.); (A.B.S.)
- Correspondence: (M.A.G.-L.); (K.W.L.)
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15
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Huang HM, Wu CW, Chen IC, Lee YC, Huang YS, Hung CY, Wu KLH. Maternal high-fructose diet induced early-onset retinopathy via the suppression of synaptic plasticity mediated by mitochondrial dysfunction. Am J Physiol Endocrinol Metab 2021; 320:E1173-E1182. [PMID: 33969706 DOI: 10.1152/ajpendo.00001.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Retinopathy is a leading cause of blindness, and there is currently no cure. Earlier identification of the progression of retinopathy could provide a better chance for intervention. Diet has profound effects on retinal function. A maternal high-fructose diet (HFD) triggers diseases in multiple organs. However, whether maternal HFD impairs retinal function in adult offspring is currently unknown. By using the rodent model of maternal HFD during pregnancy and lactation, our data indicated a reduced b-wave of electroretinography (ERG) in HFD female offspring at 3 mo of age compared with age-matched offspring of dams fed regular chow (ND). Immunofluorescence and Western blot analyses indicated that the distributions and expressions of synaptophysin, postsynaptic density protein 95 (PSD95), and phospho(p)-Ca2+/calmodulin-stimulated protein kinase IIα (CaMKIIα) were significantly suppressed in the HFD group. Furthermore, the ATP content and the mitochondrial respiratory protein, Mt CPX 4-2, were decreased. Moreover, the expressions of peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) and mitochondrial transcription factor A (TFAM) in the retina of the HFD group were downregulated. Treatment with coenzyme Q10 (Q10), a key mediator of the electron transport chain, effectively reversed these abovementioned dysfunctions. Together, these results suggested that maternal HFD impaired retinal function in adult female offspring. The mechanism underlying early-onset retinopathy may involve the reduction in the capacity of mitochondrial energy production and the suppression of synaptic plasticity. Most importantly, mitochondria could be a feasible target to reprogram maternal HFD-damaged retinal function.NEW & NOTEWORTHY In this study, we provide novel evidence that maternal high-fructose diet during gestation and lactation could induce early-onset retinopathy in adult female offspring. Of note, the insufficient energy content, downregulated mitochondrial respiratory complex 4-2, and impaired mitochondrial biogenesis might contribute to the decrease of synaptic plasticity resulting in retinal function suppression. Oral application with coenzyme Q10 for 4 wk could at least partially reverse the aforementioned molecular events and retinal function.
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Affiliation(s)
- Hsiu-Mei Huang
- Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung City, Republic of China
| | - Chih-Wei Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Republic of China
| | - I-Chun Chen
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Republic of China
| | - Yu-Chi Lee
- Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung City, Republic of China
| | - Yao-Sheng Huang
- Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung City, Republic of China
| | - Chun-Ying Hung
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Republic of China
| | - Kay L H Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Republic of China
- Department of Senior Citizen Services, National Tainan Institute of Nursing, Tainan, Republic of China
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16
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Wang A, Zou X, Wu J, Ma Q, Yuan N, Ding F, Li X, Chen J. Early-Life Stress Alters Synaptic Plasticity and mTOR Signaling: Correlation With Anxiety-Like and Cognition-Related Behavior. Front Genet 2021; 11:590068. [PMID: 33381149 PMCID: PMC7767996 DOI: 10.3389/fgene.2020.590068] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 11/24/2020] [Indexed: 12/28/2022] Open
Abstract
Early-life stress (ELS) predisposes individuals to psychiatric disorders, including anxiety and depression, and cognitive impairments later in life. However, the underlying molecular mechanisms are not completely understood. Developmental deficits in hippocampal synaptic plasticity are among the primary detrimental alterations in brain function induced by ELS. Impaired synaptic plasticity is usually accompanied by decreased synaptic proteins, such as postsynaptic density 95 (PSD95) and synaptophysin, which are important for synaptic function. The mTOR signaling pathway plays a vital role in regulating protein translation, and mTOR activation is functionally associated with synaptic protein synthesis. In the present study, we observed whether ELS impacts synaptic protein synthesis and mTOR signaling, which is involved in synaptic plasticity. Herein, we established a maternal separation (MS) and chronic restraint stress (CRS) model and evaluated anxiety-like behavior and cognitive function (e.g., learning and memory) in adulthood through behavioral examination and analyzed hippocampal expression levels of PSD95 and synaptophysin. To explore whether the mTOR signaling pathway was associated with ELS, we also examined the activity of mTOR and s6. The behavior tests indicated that maternally separated mice showed increased anxiety-like behavior and cognitive impairments. PSD95 and synaptophysin mRNA and protein expression levels were decreased in the hippocampus, and phosphorylated mTOR and phosphorylated s6 were significantly decreased in maternally separated mice vs. those not exposed to MS. Our data demonstrate that MS impairs synaptic plasticity and inhibits mTOR signaling, specifically via s6. Therefore, we speculate that ELS decreased synaptic plasticity via the inhibition of the mTOR pathway in the hippocampus, which may underlie vulnerability to stress and mental disorders in adulthood.
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Affiliation(s)
- Anfeng Wang
- School of Basic Medical Science, Hubei University of Chinese Medicine, Wuhan, China
| | - Xiaojuan Zou
- School of Basic Medical Science, Hubei University of Chinese Medicine, Wuhan, China
| | - Jiajia Wu
- School of Basic Medical Science, Hubei University of Chinese Medicine, Wuhan, China
| | - Qingyu Ma
- Formula-Pattern Research Center, School of Traditional Chinese Medicine, Jinan University, Guangzhou, China
| | - Naijun Yuan
- Formula-Pattern Research Center, School of Traditional Chinese Medicine, Jinan University, Guangzhou, China
| | - Fengmin Ding
- School of Basic Medical Science, Hubei University of Chinese Medicine, Wuhan, China
| | - Xiaojuan Li
- Formula-Pattern Research Center, School of Traditional Chinese Medicine, Jinan University, Guangzhou, China
| | - Jiaxu Chen
- School of Basic Medical Science, Hubei University of Chinese Medicine, Wuhan, China.,Formula-Pattern Research Center, School of Traditional Chinese Medicine, Jinan University, Guangzhou, China.,School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
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17
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CCL5 promotion of bioenergy metabolism is crucial for hippocampal synapse complex and memory formation. Mol Psychiatry 2021; 26:6451-6468. [PMID: 33931731 PMCID: PMC8760051 DOI: 10.1038/s41380-021-01103-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 03/10/2021] [Accepted: 04/06/2021] [Indexed: 12/13/2022]
Abstract
Glucoregulatory efficiency and ATP production are key regulators for neuronal plasticity and memory formation. Besides its chemotactic and neuroinflammatory functions, the CC chemokine--CCL5 displays neurotrophic activity. We found impaired learning-memory and cognition in CCL5-knockout mice at 4 months of age correlated with reduced hippocampal long-term potentiation and impaired synapse structure. Re-expressing CCL5 in knockout mouse hippocampus restored synaptic protein expression, neuronal connectivity and cognitive function. Using metabolomics coupled with FDG-PET imaging and seahorse analysis, we found that CCL5 participates in hippocampal fructose and mannose degradation, glycolysis, gluconeogenesis as well as glutamate and purine metabolism. CCL5 additionally supports mitochondrial structural integrity, purine synthesis, ATP generation, and subsequent aerobic glucose metabolism. Overexpressing CCL5 in WT mice also enhanced memory-cognition performance as well as hippocampal neuronal activity and connectivity through promotion of de novo purine and glutamate metabolism. Thus, CCL5 actions on glucose aerobic metabolism are critical for mitochondrial function which contribute to hippocampal spine and synapse formation, improving learning and memory.
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18
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Luo S, Hou Y, Zhang Y, Feng L, Hunter RG, Yuan P, Jia Y, Li H, Wang G, K Manji H, S McEwen B, Xiao C, Bao H, Du J. Bag-1 mediates glucocorticoid receptor trafficking to mitochondria after corticosterone stimulation: Potential role in regulating affective resilience. J Neurochem 2020; 158:358-372. [PMID: 33025573 DOI: 10.1111/jnc.15211] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 08/31/2020] [Accepted: 09/29/2020] [Indexed: 01/03/2023]
Abstract
Molecular abnormalities within the Glucocorticoid Receptor (GR) stress signaling pathway involved in dysfunction of mitochondria and confer vulnerability to stress-related psychiatric disorders. Bcl-2 associated athanogene (Bag-1) is a target for the actions of mood stabilizers. Bag-1 interacts with GR, thereby regulating glucocorticoid function. In this study, we investigate the potential role of Bag-1 in regulating GR translocation into mitochondria. Corticosterone (CORT) treatment significantly enhanced Bag-1/GR complex formation and GR mitochondrial translocation in cultured rat cortical neurons after treatment for 30 min and 24 hr. By contrast, after stimulation with CORT for 3 days, localization of the Bag-1/GR complex and mitochondrial GR were reduced. Similar results were obtained in mice, in which administrated CORT in drinking water for 21 days significantly impaired the GR levels in the mitochondria, while Bag-1 over-expression rescued this reduction. Furthermore, chronic CORT exposure led to anhedonia-like and depression-like behaviors in the sucrose-consumption test and forced swimming test, and these behaviors were rescued by Bag-1 over-expression. These results suggest that Bag-1 mediates GR trafficking to mitochondria and regulates affective resilience in response to a CORT increase and provide potential insight into the mechanisms by which Bag-1 and GR could contribute to the physiology and pathogenesis of psychiatric disorders in response to the change of stress hormone.
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Affiliation(s)
- Shaolei Luo
- School of Medicine, Yunnan University, Kunming, Yunnan, P. R. China
| | - Yangyang Hou
- School of Medicine, Yunnan University, Kunming, Yunnan, P. R. China
| | - Yaping Zhang
- School of Medicine, Yunnan University, Kunming, Yunnan, P. R. China
| | - Lei Feng
- The National Clinical Research Center for Mental Disorders, Beijing Anding Hospital, & Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Richard G Hunter
- Department of Psychology, Developmental and Brain Sciences, University of Massachusetts Boston, Boston, MA, USA
| | - Peixiong Yuan
- Experimental Therapeutics & Pathophysiology Branch, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Yue Jia
- School of Medicine, Yunnan University, Kunming, Yunnan, P. R. China
| | - Haoran Li
- School of Medicine, Yunnan University, Kunming, Yunnan, P. R. China
| | - Gang Wang
- The National Clinical Research Center for Mental Disorders, Beijing Anding Hospital, & Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | | | - Bruce S McEwen
- Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, New York, NY, USA
| | - Chunjie Xiao
- School of Medicine, Yunnan University, Kunming, Yunnan, P. R. China
| | - Hongkun Bao
- School of Medicine, Yunnan University, Kunming, Yunnan, P. R. China
| | - Jing Du
- School of Medicine, Yunnan University, Kunming, Yunnan, P. R. China.,The National Clinical Research Center for Mental Disorders, Beijing Anding Hospital, & Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
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19
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Effects of resveratrol on the levels of ATP, 5-HT and GAP-43 in the hippocampus of mice exposed to chronic unpredictable mild stress. Neurosci Lett 2020; 735:135232. [PMID: 32621948 DOI: 10.1016/j.neulet.2020.135232] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 05/28/2020] [Accepted: 07/01/2020] [Indexed: 12/13/2022]
Abstract
Growing evidence suggested that energy deficiency might be involved in the pathophysiological mechanism of depression. Energy deficiency, mainly results from mitochondrial damage, can lead to the dysfunction of synaptic neurotransmission, and further cause depressive-like behavior. The antidepressant effect of resveratrol had been widely demonstrated in previous studies; however, the underlying mechanism remains poorly understood. The present study aimed to investigate whether the antidepressant effects of resveratrol involved in the energy levels and neurotransmission in the hippocampus. We found that resveratrol and fluoxetine significantly attenuated depressive-like behaviors induced by chronic unpredictable mild stress (CUMS), which evidenced by the increased sucrose preference and the reduced immobility time in a forced swimming test. In addition, resveratrol increased hippocampal ATP levels, decreased Na+-K+-ATPase and pyruvate levels, and upregulated the levels of mitochondrial DNA (mtDNA), mRNA expression of sirtuin (SIRT)1 and peroxisome proliferator-activated receptor γ coactivator (PGC)1α. Furthermore, resveratrol and fluoxetine increased serotonin (5-HT) levels and downregulated the mRNA expression of 5-HT transporter (SERT) in the hippocampus. The decreased protein expression of growth-associated protein (GAP)-43 induced by CUMS was also ameliorated by resveratrol and fluoxetine. These findings demonstrated the antidepressant effects of resveratrol and suggested that resveratrol was able to promote mitochondrial biogenesis, enhance ATP and 5-HT levels, as well as upregulate GAP-43 expression in the hippocampus.
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20
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Taylor-Giorlando M, Scheinost D, Ment L, Rothman D, Horvath TL. Prefrontal Cortical and Behavioral Adaptations to Surgical Delivery Mediated by Metabolic Principles. Cereb Cortex 2019; 29:5061-5071. [PMID: 30877804 PMCID: PMC6918927 DOI: 10.1093/cercor/bhz046] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 02/06/2019] [Accepted: 02/19/2019] [Indexed: 01/21/2023] Open
Abstract
We previously observed an association between mode of delivery and brain mitochondrial mechanisms in pups. We also showed that mitochondrial processes impact adult behavior. However, no experimental data is available to causally connect mode of delivery with cellular processes of neurons in the cerebral cortex and adult behavior. Here we show that surgical delivery of pups alters mitochondrial dynamics and spine synapses of layer 3 pyramidal neurons of the prefrontal cortex compared to the values of mice delivered vaginally. These alterations in ultrastructure seen in adult mice delivered surgically were associated with the development of behavioral phenotypes resembling those characteristic of animal models of psychiatric illness. This included impaired performance in prepulse inhibition as well as hyperlocomotion in the open field and elevated plus maze tests. Knocking out a mitochondria-related gene, UCP-2, blocked cellular and behavioral adaptations induced by surgical delivery. These results highlight a crucial role for brain mitochondrial adaptations in the process of birth to affect neuronal circuitry in support of normal and altered adult behaviors. Further, these findings were supported with neuroimaging data from human neonates delivered vaginally and surgically, suggesting that the murine findings have human clinical relevance.
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Affiliation(s)
- Melissa Taylor-Giorlando
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Dustin Scheinost
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
- Department of Statistics and Data Science, Yale University, New Haven, CT, USA
- Child Study Center, Yale School of Medicine, New Haven, CT, USA
| | - Laura Ment
- Department of Pediatrics, Yale School of Medicine, New Haven, CT, USA
- Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Dough Rothman
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Tamas L Horvath
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Department of Comparative Medicine, Yale School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, USA
- Department of Ob/Gyn and Reproductive Sciences, Yale School of Medicine, New Haven, CT, USA
- Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, Hungary
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21
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Fractionated mitochondrial magnetic separation for isolation of synaptic mitochondria from brain tissue. Sci Rep 2019; 9:9656. [PMID: 31273236 PMCID: PMC6609636 DOI: 10.1038/s41598-019-45568-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 04/08/2019] [Indexed: 12/21/2022] Open
Abstract
While mitochondria maintain essential cellular functions, such as energy production, calcium homeostasis, and regulating programmed cellular death, they also play a major role in pathophysiology of many neurological disorders. Furthermore, several neurodegenerative diseases are closely linked with synaptic damage and synaptic mitochondrial dysfunction. Unfortunately, the ability to assess mitochondrial dysfunction and the efficacy of mitochondrial-targeted therapies in experimental models of neurodegenerative disease and CNS injury is limited by current mitochondrial isolation techniques. Density gradient ultracentrifugation (UC) is currently the only technique that can separate synaptic and non-synaptic mitochondrial sub-populations, though small brain regions cannot be assayed due to low mitochondrial yield. To address this limitation, we used fractionated mitochondrial magnetic separation (FMMS), employing magnetic anti-Tom22 antibodies, to develop a novel strategy for isolation of functional synaptic and non-synaptic mitochondria from mouse cortex and hippocampus without the usage of UC. We compared the yield and functionality of mitochondria derived using FMMS to those derived by UC. FMMS produced 3x more synaptic mitochondrial protein yield compared to UC from the same amount of tissue, a mouse hippocampus. FMMS also has increased sensitivity, compared to UC separation, to measure decreased mitochondrial respiration, demonstrated in a paradigm of mild closed head injury. Taken together, FMMS enables improved brain-derived mitochondrial yield for mitochondrial assessments and better detection of mitochondrial impairment in CNS injury and neurodegenerative disease.
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22
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Coelho DS, Moreno E. Emerging links between cell competition and Alzheimer's disease. J Cell Sci 2019; 132:132/13/jcs231258. [PMID: 31263078 DOI: 10.1242/jcs.231258] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Alzheimer's disease (AD) causes a progressive loss of memory and other cognitive functions, which inexorably debilitates patients. There is still no cure for AD and effective treatments to delay or revert AD are urgently needed. On a molecular level, the excessive accumulation of amyloid-β (Aβ) peptides triggers a complex cascade of pathological events underlying neuronal death, whose details are not yet completely understood. Our laboratory recently discovered that cell competition may play a protective role against AD by eliminating less fit neurons from the brain of Aβ-transgenic flies. Loss of Aβ-damaged neurons through fitness comparison with healthy counterparts is beneficial for the organism, delaying cognitive decline and motor disability. In this Review, we introduce the molecular mechanisms of cell competition, including seminal works on the field and latest advances regarding genetic triggers and effectors of cell elimination. We then describe the biological relevance of competition in the nervous system and discuss how competitive interactions between neurons may arise and be exacerbated in the context of AD. Selection of neurons through fitness comparison is a promising, but still emerging, research field that may open new avenues for the treatment of neurological disorders.
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Affiliation(s)
- Dina S Coelho
- Cell Fitness Laboratory, Champalimaud Centre for the Unknown, Av. Brasília., 1400-038 Lisbon, Portugal
| | - Eduardo Moreno
- Cell Fitness Laboratory, Champalimaud Centre for the Unknown, Av. Brasília., 1400-038 Lisbon, Portugal
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23
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Todorov G, Cunha C. Hypothesis: Regulation of neuroplasticity may involve I-motif and G-quadruplex DNA formation modulated by epigenetic mechanisms. Med Hypotheses 2019; 127:129-135. [PMID: 31088636 DOI: 10.1016/j.mehy.2019.04.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 04/04/2019] [Accepted: 04/08/2019] [Indexed: 01/12/2023]
Abstract
Recent studies demonstrated the existence in vivo of various functional DNA structures that differ from the double helix. The G-quadruplex (G4) and intercalated motif (I-motif or IM) DNA structures are formed as knots where, correspondingly, guanines or cytosines on the same strand of DNA bind to each other. There are grounds to believe that G4 and IM sequences play a significant role in regulating gene expression considering their tendency to be found in or near regulatory sites (such as promoters, enhancers, and telomeres) as well as the correlation between the prevalence of G4 or IM conformations and specific phases of cell cycle. Notably, G4 and IM capable sequences tend to be found on the opposite strands of the same DNA site with at most one of the two structures formed at any given time. The recent evidence that K+, Mg2+ concentrations directly affect IM formation (and likely G4 formation indirectly) lead us to believe that these structures may play a major role in synaptic plasticity of neurons, and, therefore, in a variety of central nervous system (CNS) functions including memory, learning, habitual behaviors, pain perception and others. Furthermore, epigenetic mechanisms, which have an important role in synaptic plasticity and memory formation, were also shown to influence formation and stability of G4s and IMs. Our hypothesis is that non-canonical DNA and RNA structures could be an integral part of neuroplasticity control via gene expression regulation at the level of transcription, translation and splicing. We propose that the regulatory activity of DNA IM and G4 structures is modulated by DNA methylation/demethylation of the IM and/or G4 sequences, which facilitates the switch between canonical and non-canonical conformation. Other neuronal mechanisms interacting with the formation and regulatory activity of non-canonical DNA and RNA structures, particularly G4, IM and triplexes, may involve microRNAs as well as ion and proton fluxes. We are proposing experiments in acute brain slices and in vivo to test our hypothesis. The proposed studies would provide new insights into fundamental neuronal mechanisms in health and disease and potentially open new avenues for treating mental health disorders.
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Affiliation(s)
- German Todorov
- Emotional Brain Institute, Nathan Kline Institute, Orangeburg, NY, USA
| | - Catarina Cunha
- Emotional Brain Institute, Nathan Kline Institute, Orangeburg, NY, USA.
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24
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Dysfunctional Mitochondrial Bioenergetics and Synaptic Degeneration in Alzheimer Disease. Int Neurourol J 2019; 23:S5-10. [PMID: 30832462 PMCID: PMC6433209 DOI: 10.5213/inj.1938036.018] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Accepted: 02/15/2019] [Indexed: 12/21/2022] Open
Abstract
Synapses are sites of high energy demand which are dependent on high levels of mitochondrial derived adenosine triphosphate. Mitochondria within synaptic structures are key for maintenance of functional neurotransmission and this critical biological process is modulated by energy metabolism, mitochondrial distribution, mitochondrial trafficking, and cellular synaptic calcium flux. Synapse loss is presumed to be an early yet progressive pathological event in Alzheimer disease (AD), resulting in impaired cognitive function and memory loss which is particularly prevalent at later stages of disease. Supporting evidence from AD patients and animal models suggests that pathological mitochondrial dynamics indeed occurs early and is highly associated with synaptic lesions and degeneration in AD neurons. This review comprehensively highlights recent findings that describe how synaptic mitochondria pathology involves dysfunctional trafficking of this organelle, to maladaptive epigenetic contributions affecting mitochondrial function in AD. We further discuss how these negative, dynamic alterations impact synaptic function associated with AD. Finally, this review explores how antioxidant therapeutic approaches targeting mitochondria in AD can further clinical research and basic science investigations to advance our in-depth understanding of the pathogenesis of AD.
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25
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Kim JI, Lee SY, Park M, Kim SY, Kim JW, Kim SA, Kim BN. Peripheral Mitochondrial DNA Copy Number is Increased in Korean Attention-Deficit Hyperactivity Disorder Patients. Front Psychiatry 2019; 10:506. [PMID: 31379624 PMCID: PMC6656858 DOI: 10.3389/fpsyt.2019.00506] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 06/27/2019] [Indexed: 01/10/2023] Open
Abstract
The involvement of mitochondrial dysfunction in the pathophysiology of attention-deficit hyperactivity disorder (ADHD) has been suggested in several reports. Mitochondrial DNA (mtDNA) copy number as well as methylation of the D-loop region and peroxisome-proliferator-activated receptor γ co-activator-1α (PPARGC1A) are considered biomarkers for mitochondrial dysfunction. We compared the mtDNA copy number and methylation ratio of the D-loop region and PPARGC1A between ADHD patients and controls and also among ADHD subtypes. The present study included 70 subjects with ADHD and 70 age- and gender-matched healthy controls (HCs). We measured the relative mtDNA copy number in peripheral blood cells using quantitative polymerase chain reaction (qPCR), and the methylation ratio was measured using methylation-specific PCR (MSP) after bisulfite conversion. The relative mtDNA copy number was significantly higher in ADHD patients than in HCs (p = 0.028). The mtDNA methylation ratio of PPARGC1A was decreased in ADHD patients compared with HCs (p = 0.008). After adjusting for IQ level, only the mtDNA copy number differed between the ADHD and HCs (p = 0.01). There was a significant difference in the methylation ratio of PPARGC1A among ADHD subtypes. These results suggest the possible involvement of mitochondrial dysfunction in the pathophysiology of ADHD. Further large cohort studies investigating the correlation between clinical markers and biomarkers of mitochondrial dysfunction are warranted.
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Affiliation(s)
- Johanna Inhyang Kim
- Department of Psychiatry, Hanyang University Medical Center, Seoul, South Korea
| | - Soo-Young Lee
- Department of Pharmacology, School of Medicine, Eulji University, Daejeon, South Korea
| | - Mira Park
- Department of Preventive Medicine, School of Medicine, Eulji University, Daejeon, South Korea
| | - Si Yeon Kim
- Department of Preventive Medicine, School of Medicine, Eulji University, Daejeon, South Korea
| | - Jae-Won Kim
- Division of Child and Adolescent Psychiatry, Department of Psychiatry, Seoul National University College of Medicine, Seoul, South Korea
| | - Soon Ae Kim
- Department of Pharmacology, School of Medicine, Eulji University, Daejeon, South Korea
| | - Bung-Nyun Kim
- Division of Child and Adolescent Psychiatry, Department of Psychiatry, Seoul National University College of Medicine, Seoul, South Korea
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Lapp HE, Ahmed S, Moore CL, Hunter RG. Toxic stress history and hypothalamic-pituitary-adrenal axis function in a social stress task: Genetic and epigenetic factors. Neurotoxicol Teratol 2019; 71:41-49. [DOI: 10.1016/j.ntt.2018.01.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 01/24/2018] [Accepted: 01/29/2018] [Indexed: 01/12/2023]
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Agathokleous E, Kitao M, Calabrese EJ. New insights into the role of melatonin in plants and animals. Chem Biol Interact 2018; 299:163-167. [PMID: 30553720 DOI: 10.1016/j.cbi.2018.12.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 12/05/2018] [Accepted: 12/12/2018] [Indexed: 12/15/2022]
Abstract
Melatonin is a hormone produced in animals by the pineal gland and in plants under stress. Melatonin research has expanded rapidly, affecting an impressive enhancement in the understanding of its functions in plants and animals. However, far less focus has been directed to clarifying the nature of melatonin dose-response relationships. Here, we provide substantial evidence of melatonin-induced biphasic dose-response relationships from a series of independent studies involving plant and animal models. The characteristics of these dose responses are similar to those of the broad toxicological and pharmacological hormesis literature. Our analysis suggests that melatonin, in coordination with the circadian rhythms, is involved in stress adaptive responses, and may act as a conditioning agent protecting organisms against subsequent health threats within an hormetic framework. Incorporation of melatonin-induced hormesis in research protocols has the potential to enhance the treatment of neuropsychiatric diseases, cancers, and other animal diseases, as well as protection against environmental stress and to increase plant productivity.
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Affiliation(s)
- Evgenios Agathokleous
- Hokkaido Research Center, Forestry and Forest Products Research Institute (FFPRI), Forest Research and Management Organization, 7 Hitsujigaoka, Sapporo, Hokkaido, 062-8516, Japan; Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Sapporo, Hokkaido, 060-8589, Japan.
| | - Mitsutoshi Kitao
- Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9, Sapporo, Hokkaido, 060-8589, Japan.
| | - Edward J Calabrese
- Department of Environmental Health Sciences, Morrill I, N344, University of Massachusetts, Amherst, MA, 01003, USA.
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Singer W, Manthey M, Panford-Walsh R, Matt L, Geisler HS, Passeri E, Baj G, Tongiorgi E, Leal G, Duarte CB, Salazar IL, Eckert P, Rohbock K, Hu J, Strotmann J, Ruth P, Zimmermann U, Rüttiger L, Ott T, Schimmang T, Knipper M. BDNF-Live-Exon-Visualization (BLEV) Allows Differential Detection of BDNF Transcripts in vitro and in vivo. Front Mol Neurosci 2018; 11:325. [PMID: 30319348 PMCID: PMC6170895 DOI: 10.3389/fnmol.2018.00325] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 08/22/2018] [Indexed: 12/16/2022] Open
Abstract
Bdnf exon-IV and exon-VI transcripts are driven by neuronal activity and are involved in pathologies related to sleep, fear or memory disorders. However, how their differential transcription translates activity changes into long-lasting network changes is elusive. Aiming to trace specifically the network controlled by exon-IV and -VI derived BDNF during activity-dependent plasticity changes, we generated a transgenic reporter mouse for B DNF- l ive- e xon- v isualization (BLEV), in which expression of Bdnf exon-IV and -VI can be visualized by co-expression of CFP and YFP. CFP and YFP expression was differentially activated and targeted in cell lines, primary cultures and BLEV reporter mice without interfering with BDNF protein synthesis. CFP and YFP expression, moreover, overlapped with BDNF protein expression in defined hippocampal neuronal, glial and vascular locations in vivo. So far, activity-dependent BDNF cannot be explicitly monitored independent of basal BDNF levels. The BLEV reporter mouse therefore provides a new model, which can be used to test whether stimulus-induced activity-dependent changes in BDNF expression are instrumental for long-lasting plasticity modifications.
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Affiliation(s)
- Wibke Singer
- Department of Otolaryngology, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Marie Manthey
- Department of Otolaryngology, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Rama Panford-Walsh
- Department of Otolaryngology, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Lucas Matt
- Department of Pharmacology, Institute of Pharmacy, Toxicology and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Hyun-Soon Geisler
- Department of Otolaryngology, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Eleonora Passeri
- Department of Otolaryngology, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Gabriele Baj
- B.R.A.I.N. Centre for Neuroscience, Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Enrico Tongiorgi
- B.R.A.I.N. Centre for Neuroscience, Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Graciano Leal
- Centre for Neuroscience and Cell Biology (CNC), Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Carlos B. Duarte
- Centre for Neuroscience and Cell Biology (CNC), Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Ivan L. Salazar
- Centre for Neuroscience and Cell Biology (CNC), Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Philipp Eckert
- Department of Otolaryngology, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Karin Rohbock
- Department of Otolaryngology, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Jing Hu
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
| | - Jörg Strotmann
- Department of Physiology, Institute of Physiology, University of Hohenheim, Stuttgart, Germany
| | - Peter Ruth
- Department of Pharmacology, Institute of Pharmacy, Toxicology and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Ulrike Zimmermann
- Department of Otolaryngology, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Thomas Ott
- Transgenic Facility Tübingen, University of Tübingen, Tübingen, Germany
| | - Thomas Schimmang
- Instituto de Biologíay Genética Molecular, Universidad de Valladolid y Consejo Superior de Investigaciones Científicas, Valladolid, Spain
| | - Marlies Knipper
- Department of Otolaryngology, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
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Hofmeier B, Wolpert S, Aldamer ES, Walter M, Thiericke J, Braun C, Zelle D, Rüttiger L, Klose U, Knipper M. Reduced sound-evoked and resting-state BOLD fMRI connectivity in tinnitus. NEUROIMAGE-CLINICAL 2018; 20:637-649. [PMID: 30202725 PMCID: PMC6128096 DOI: 10.1016/j.nicl.2018.08.029] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 08/29/2018] [Accepted: 08/30/2018] [Indexed: 01/02/2023]
Abstract
The exact neurophysiological basis of chronic tinnitus, which affects 10-15% of the population, remains unknown and is controversial at many levels. It is an open question whether phantom sound perception results from increased central neural gain or not, a crucial question for any future therapeutic intervention strategies for tinnitus. We performed a comprehensive study of mild hearing-impaired participants with and without tinnitus, excluding participants with co-occurrences of hyperacusis. A right-hemisphere correlation between tinnitus loudness and auditory perceptual difficulty was observed in the tinnitus group, independent of differences in hearing thresholds. This correlation was linked to reduced and delayed sound-induced suprathreshold auditory brain responses (ABR wave V) in the tinnitus group, suggesting subsided rather than exaggerated central neural responsiveness. When anatomically predefined auditory regions of interest were analysed for altered sound-evoked BOLD fMRI activity, it became evident that subcortical and cortical auditory regions and regions involved in sound detection (posterior insula, hippocampus), responded with reduced BOLD activity in the tinnitus group, emphasizing reduced, rather than increased, central neural gain. Regarding previous findings of evoked BOLD activity being linked to positive connectivities at rest, we additionally analysed r-fcMRI responses in anatomically predefined auditory regions and regions associated with sound detection. A profound reduction in positive interhemispheric connections of homologous auditory brain regions and a decline in the positive connectivities between lower auditory brainstem regions and regions involved in sound detection (hippocampus, posterior insula) were observed in the tinnitus group. The finding went hand-in-hand with the emotional (amygdala, anterior insula) and temporofrontal/stress-regulating regions (prefrontal cortex, inferior frontal gyrus) that were no longer positively connected with auditory cortex regions in the tinnitus group but were instead positively connected to lower-level auditory brainstem regions. Delayed sound processing, reduced sound-evoked BOLD fMRI activity and altered r-fcMRI in the auditory midbrain correlated in the tinnitus group and showed right hemisphere dominance as did tinnitus loudness and perceptual difficulty. The findings suggest that reduced central neural gain in the auditory stream may lead to phantom perception through a failure to energize attentional/stress-regulating networks for contextualization of auditory-specific information. Reduced auditory-specific information flow in tinnitus has until now escaped detection in humans, as low-level auditory brain regions were previously omitted from neuroimaging studies. TRIAL REGISTRATION German Clinical Trials Register DRKS0006332.
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Key Words
- ABR wave
- ABR, auditory brainstem response
- BA, Brodmann area
- BA13A, anterior insula
- BA13P, posterior insula
- BA28, entorhinal cortex
- BB-chirp, broadband chirp
- BERA, brainstem-evoked response audiometry
- CN, cochlear nucleus
- CSF, cerebrospinal fluid
- Cortisol
- DL, dorsolateral
- EFR, envelope-followed responses
- ENT, ear, nose and throat
- FA, flip angle
- FDR, false discovery rate
- FOV, field of view
- FWHM, full width at half maximum
- G-H-S, Goebel-Hiller-Score
- HF-chirp, high-frequency chirp
- HPA, hypothalamic-pituitary-adrenal
- High-SR AF, high-spontaneous firing rates auditory fibers
- IC, inferior colliculus
- L, left
- LF-chirp, low-frequency chirp
- Low-SR AF, low-spontaneous firing rates auditory fibers
- M, medial
- MGB, medial geniculate body
- MNI, Montreal Neurological Institute
- PFC, prefrontal cortex
- PTA, pure tone audiogram
- R, right
- ROI, region of interest
- SD, standard deviation
- SOC, superior olivary complex
- SPL, sound pressure level
- SPM, Statistical Parametric Mapping
- TA, acquisition time
- TE, echo time
- TR, repetition time
- Tinnitus
- VBM, voxel-based morphometry
- fMRI
- r-fcMRI
- rCBF, resting-state cerebral blood flow
- rCBV, resting-state cerebral blood volume
- zFC, z-values functional connectivity
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Affiliation(s)
- Benedikt Hofmeier
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - Stephan Wolpert
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - Ebrahim Saad Aldamer
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - Moritz Walter
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - John Thiericke
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany/HNO Ärzte Praxis Part GmbB, Aschaffenburg, Germany
| | - Christoph Braun
- MEG Center, University Hospital Tübingen, Otfried-Müller-Str. 47, D-72076 Tübingen, Germany
| | - Dennis Zelle
- Section of Physiological Acoustics and Communication, Department of Otolaryngology, Head and Neck Surgery, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany
| | - Uwe Klose
- Department of Diagnostic and Interventional Neuroradiology, University Hospital Tübingen, Hoppe-Seyler-Str. 3, D-73076 Tübingen, Germany.
| | - Marlies Knipper
- Department of Otolaryngology, Head and Neck Surgery, Hearing Research Center Tübingen, Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Str. 5, D-72076 Tübingen, Germany.
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30
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Ridout KK, Khan M, Ridout SJ. Adverse Childhood Experiences Run Deep: Toxic Early Life Stress, Telomeres, and Mitochondrial DNA Copy Number, the Biological Markers of Cumulative Stress. Bioessays 2018; 40:e1800077. [DOI: 10.1002/bies.201800077] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 06/20/2018] [Indexed: 01/01/2023]
Affiliation(s)
- Kathryn K. Ridout
- Department of Psychiatry; Kaiser Permanente; San Jose CA 95123 USA
- Department of Psychiatry and Human Behavior; Alpert Medical School of Brown University; Providence RI 02906 USA
| | - Mariam Khan
- Oncology Clinical Trials Department; Kaiser Permanente; San Jose CA 95123 USA
| | - Samuel J. Ridout
- Department of Psychiatry; Kaiser Permanente; San Jose CA 95123 USA
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31
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Matt L, Eckert P, Panford-Walsh R, Geisler HS, Bausch AE, Manthey M, Müller NIC, Harasztosi C, Rohbock K, Ruth P, Friauf E, Ott T, Zimmermann U, Rüttiger L, Schimmang T, Knipper M, Singer W. Visualizing BDNF Transcript Usage During Sound-Induced Memory Linked Plasticity. Front Mol Neurosci 2018; 11:260. [PMID: 30127717 PMCID: PMC6089339 DOI: 10.3389/fnmol.2018.00260] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 07/12/2018] [Indexed: 12/14/2022] Open
Abstract
Activity-dependent BDNF (brain-derived neurotrophic factor) expression is hypothesized to be a cue for the context-specificity of memory formation. So far, activity-dependent BDNF cannot be explicitly monitored independently of basal BDNF levels. We used the BLEV (BDNF-live-exon-visualization) reporter mouse to specifically detect activity-dependent usage of Bdnf exon-IV and -VI promoters through bi-cistronic co-expression of CFP and YFP, respectively. Enriching acoustic stimuli led to improved peripheral and central auditory brainstem responses, increased Schaffer collateral LTP, and enhanced performance in the Morris water maze. Within the brainstem, neuronal activity was increased and accompanied by a trend for higher expression levels of Bdnf exon-IV-CFP and exon-VI-YFP transcripts. In the hippocampus BDNF transcripts were clearly increased parallel to changes in parvalbumin expression and were localized to specific neurons and capillaries. Severe acoustic trauma, in contrast, elevated neither Bdnf transcript levels, nor auditory responses, parvalbumin or LTP. Together, this suggests that critical sensory input is essential for recruitment of activity-dependent auditory-specific BDNF expression that may shape network adaptation.
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Affiliation(s)
- Lucas Matt
- Department of Pharmacology, Institute of Pharmacy, Toxicology, and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Philipp Eckert
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Rama Panford-Walsh
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Hyun-Soon Geisler
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Anne E Bausch
- Department of Pharmacology, Institute of Pharmacy, Toxicology, and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Marie Manthey
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Nicolas I C Müller
- Animal Physiology Group, Department of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Csaba Harasztosi
- Section of Physiological Acoustics and Communication, Department of Otolaryngology, Tübingen Hearing Research Center, University of Tübingen, Tübingen, Germany
| | - Karin Rohbock
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Peter Ruth
- Department of Pharmacology, Institute of Pharmacy, Toxicology, and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Eckhard Friauf
- Animal Physiology Group, Department of Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Thomas Ott
- Transgenic Facility Tübingen, University of Tübingen, Tübingen, Germany
| | - Ulrike Zimmermann
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Thomas Schimmang
- Instituto de Biologíay Genética Molecular, Universidad de Valladolid, Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - Marlies Knipper
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
| | - Wibke Singer
- Department of Otolaryngology, Tübingen Hearing Research Centre, Molecular Physiology of Hearing, University of Tübingen, Tübingen, Germany
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Chiang S, Kalinowski DS, Jansson PJ, Richardson DR, Huang MLH. Mitochondrial dysfunction in the neuro-degenerative and cardio-degenerative disease, Friedreich's ataxia. Neurochem Int 2018; 117:35-48. [PMID: 28782591 DOI: 10.1016/j.neuint.2017.08.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 07/25/2017] [Accepted: 08/03/2017] [Indexed: 01/09/2023]
Abstract
Mitochondrial homeostasis is essential for maintaining healthy cellular function and survival. The detrimental involvement of mitochondrial dysfunction in neuro-degenerative diseases has recently been highlighted in human conditions, such as Parkinson's, Alzheimer's and Huntington's disease. Friedreich's ataxia (FA) is another neuro-degenerative, but also cardio-degenerative condition, where mitochondrial dysfunction plays a crucial role in disease progression. Deficient expression of the mitochondrial protein, frataxin, is the primary cause of FA, which leads to adverse alterations in whole cell and mitochondrial iron metabolism. Dys-regulation of iron metabolism in these compartments, results in the accumulation of inorganic iron deposits in the mitochondrial matrix that is thought to potentiate oxidative damage observed in FA. Therefore, the maintenance of mitochondrial homeostasis is crucial in the progression of neuro-degenerative conditions, particularly in FA. In this review, vital mitochondrial homeostatic processes and their roles in FA pathogenesis will be discussed. These include mitochondrial iron processing, mitochondrial dynamics (fusion and fission processes), mitophagy, mitochondrial biogenesis, mitochondrial energy production and calcium metabolism.
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Affiliation(s)
- Shannon Chiang
- Department of Pathology and Bosch Institute, University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Danuta S Kalinowski
- Department of Pathology and Bosch Institute, University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Patric J Jansson
- Department of Pathology and Bosch Institute, University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Des R Richardson
- Department of Pathology and Bosch Institute, University of Sydney, Sydney, New South Wales, 2006, Australia.
| | - Michael L-H Huang
- Department of Pathology and Bosch Institute, University of Sydney, Sydney, New South Wales, 2006, Australia.
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33
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Neonatal maternal deprivation impairs localized de novo activity-induced protein translation at the synapse in the rat hippocampus. Biosci Rep 2018; 38:BSR20180118. [PMID: 29700212 PMCID: PMC5997792 DOI: 10.1042/bsr20180118] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 04/16/2018] [Accepted: 04/24/2018] [Indexed: 11/17/2022] Open
Abstract
Neonatal neuropsychiatric stress induces alterations in neurodevelopment that can lead to irreversible damage to neuronal physiology, and social, behavioral, and cognitive skills. In addition, this culminates to an elevated vulnerability to stress and anxiety later in life. Developmental deficits in hippocampal synaptic function and plasticity are among the primary contributors of detrimental alterations in brain function induced by early-life stress. However, the underlying molecular mechanisms are not completely understood. Localized protein translation, occurring at the synapse and triggered by neuronal activity, is critical for synapse function, maintenance, and plasticity. We used a rodent model of chronic maternal deprivation to characterize the effects of early-life neuropsychiatric stress on localized de novo protein translation at synaptic connections between neurons. Synaptoneurosomal preparations isolated biochemically from the hippocampi of rat pups that were subjected to maternal deprivation were deficient in depolarization-induced activity-dependent protein translation when compared with littermate controls. Conversely, basal unstimulated protein translation was not affected. Moreover, deficits in activity-driven synaptic protein translation were significantly correlated with a reduction in phosphorylated cell survival protein kinase protein B or Akt (p473 Ser and p308 Thr), but not phosphorylated extracellular signal-regulated kinase.
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34
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Reig-Viader R, Sindreu C, Bayés À. Synaptic proteomics as a means to identify the molecular basis of mental illness: Are we getting there? Prog Neuropsychopharmacol Biol Psychiatry 2018; 84:353-361. [PMID: 28941771 DOI: 10.1016/j.pnpbp.2017.09.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 09/05/2017] [Accepted: 09/15/2017] [Indexed: 12/31/2022]
Abstract
Synapses are centrally involved in many brain disorders, particularly in psychiatric and neurodevelopmental ones. However, our current understanding of the proteomic alterations affecting synaptic performance in the majority of mental illnesses is limited. As a result, novel pharmacotherapies with improved neurological efficacy have been scarce over the past decades. The main goal of synaptic proteomics in the context of mental illnesses is to identify dysregulated molecular mechanisms underlying these conditions. Here we reviewed and performed a meta-analysis of previous neuroproteomic research to identify proteins that may be consistently dysregulated in one or several mental disorders. Notably, we found very few proteins reproducibly altered among independent experiments for any given condition or between conditions, indicating that we are still far from identifying key pathophysiological mechanisms of mental illness. We suggest that future research in the field will require higher levels of standardization and larger-scale experiments to address the challenge posed by biological and methodological variability. We strongly believe that more resources should be placed in this field as the need to identify the molecular roots of mental illnesses is highly pressing.
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Affiliation(s)
- Rita Reig-Viader
- Molecular Physiology of the Synapse Laboratory, Biomedical Research Institute Sant Pau (IIB Sant Pau), Sant Antoni Mª Claret 167, 08025 Barcelona, Spain; Universitat Autònoma de Barcelona, 08193, Bellaterra, Cerdanyola del Vallès, Spain\
| | - Carlos Sindreu
- Department of Clinical Foundations, University of Barcelona, Barcelona 08036, Spain; Institute of Neuroscience UB, Barcelona 08035, Spain
| | - Àlex Bayés
- Molecular Physiology of the Synapse Laboratory, Biomedical Research Institute Sant Pau (IIB Sant Pau), Sant Antoni Mª Claret 167, 08025 Barcelona, Spain; Universitat Autònoma de Barcelona, 08193, Bellaterra, Cerdanyola del Vallès, Spain\.
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Chen F, Danladi J, Ardalan M, Elfving B, Müller HK, Wegener G, Sanchez C, Nyengaard JR. A Critical Role of Mitochondria in BDNF-Associated Synaptic Plasticity After One-Week Vortioxetine Treatment. Int J Neuropsychopharmacol 2018; 21. [PMID: 29514282 PMCID: PMC6007239 DOI: 10.1093/ijnp/pyy022] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Preclinical studies have indicated that antidepressant effect of vortioxetine involves increased synaptic plasticity and promotion of spine maturation. Mitochondria dysfunction may contribute to the pathophysiological basis of major depressive disorder. Taking into consideration that vortioxetine increases spine number and dendritic branching in hippocampus CA1 faster than fluoxetine, we hypothesize that new spines induced by vortioxetine can rapidly form functional synapses by mitochondrial support, accompanied by increased brain-derived neurotrophic factor signaling. METHODS Rats were treated for 1 week with vortioxetine or fluoxetine at pharmacologically relevant doses. Number of synapses and mitochondria in hippocampus CA1 were quantified by electron microscopy. Brain-derived neurotrophic factor protein levels were visualized with immunohistochemistry. Gene and protein expression of synapse and mitochondria-related markers were investigated with real-time quantitative polymerase chain reaction and immunoblotting. RESULTS Vortioxetine increased number of synapses and mitochondria significantly, whereas fluoxetine had no effect after 1-week dosing. BDNF levels in hippocampus DG and CA1 were significantly higher after vortioxetine treatment. Gene expression levels of Rac1 after vortioxetine treatment were significantly increased. There was a tendency towards increased gene expression levels of Drp1 and protein levels of Rac1. However, both gene and protein levels of c-Fos were significantly decreased. Furthermore, there was a significant positive correlation between BDNF levels and mitochondria and synapse numbers. CONCLUSION Our results imply that mitochondria play a critical role in synaptic plasticity accompanied by increased BDNF levels. Rapid changes in BDNF levels and synaptic/mitochondria plasticity of hippocampus following vortioxetine compared with fluoxetine may be ascribed to vortioxetine's modulation of serotonin receptors.
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Affiliation(s)
- Fenghua Chen
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Risskov, Denmark
- Core Center for Molecular Morphology, Section for Stereology and Microscopy, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Correspondence: Fenghua Chen, Department of Clinical Medicine - Translational Neuropsychiatry Unit, Skovagervej 2, 8240 Risskov, Denmark ()
| | - Jibrin Danladi
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Risskov, Denmark
| | - Maryam Ardalan
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Risskov, Denmark
- Department of Clinical Medicine - Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| | - Betina Elfving
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Risskov, Denmark
| | - Heidi K Müller
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Risskov, Denmark
| | - Gregers Wegener
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Risskov, Denmark
- Center of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom, South Africa
- AUGUST Centre, Department of Clinical Medicine, Aarhus University, Risskov, Denmark
| | - Connie Sanchez
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Risskov, Denmark
- Alkermes, Biotechnology, Waltham, MA
| | - Jens R Nyengaard
- Core Center for Molecular Morphology, Section for Stereology and Microscopy, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Centre for Stochastic Geometry and Advanced Bioimaging, Aarhus University, Aarhus, Denmark
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Guo L, Tian J, Du H. Mitochondrial Dysfunction and Synaptic Transmission Failure in Alzheimer's Disease. J Alzheimers Dis 2018; 57:1071-1086. [PMID: 27662318 DOI: 10.3233/jad-160702] [Citation(s) in RCA: 114] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Alzheimer's disease (AD) is a chronic neurodegenerative disorder, in which multiple risk factors converge. Despite the complexity of the etiology of the disease, synaptic failure is the pathological basis of cognitive impairment, the cardinal sign of AD. Decreased synaptic density, compromised synaptic transmission, and defected synaptic plasticity are hallmark synaptic pathologies accompanying AD. However, the mechanisms by which synapses are injured in AD-related conditions have not been fully elucidated. Mitochondria are a critical organelle in neurons. The pivotal role of mitochondria in supporting synaptic function and the concomitant occurrence of mitochondrial dysfunction with synaptic stress in postmortem AD brains as well as AD animal models seem to lend the credibility to the hypothesis that mitochondrial defects underlie synaptic failure in AD. This concept is further strengthened by the protective effect of mitochondrial medicine on synaptic function against the toxicity of amyloid-β, a key player in the pathogenesis of AD. In this review, we focus on the association between mitochondrial dysfunction and synaptic transmission deficits in AD. Impaired mitochondrial energy production, deregulated mitochondrial calcium handling, excess mitochondrial reactive oxygen species generation and release play a crucial role in mediating synaptic transmission deregulation in AD. The understanding of the role of mitochondrial dysfunction in synaptic stress may lead to novel therapeutic strategies for the treatment of AD through the protection of synaptic transmission by targeting to mitochondrial deficits.
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Affiliation(s)
- Lan Guo
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Jing Tian
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX, USA
| | - Heng Du
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX, USA.,Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, China
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The Stress-Induced Transcription Factor NR4A1 Adjusts Mitochondrial Function and Synapse Number in Prefrontal Cortex. J Neurosci 2018; 38:1335-1350. [PMID: 29295823 PMCID: PMC5815341 DOI: 10.1523/jneurosci.2793-17.2017] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/10/2017] [Accepted: 12/08/2017] [Indexed: 12/28/2022] Open
Abstract
The energetic costs of behavioral chronic stress are unlikely to be sustainable without neuronal plasticity. Mitochondria have the capacity to handle synaptic activity up to a limit before energetic depletion occurs. Protective mechanisms driven by the induction of neuronal genes likely evolved to buffer the consequences of chronic stress on excitatory neurons in prefrontal cortex (PFC), as this circuitry is vulnerable to excitotoxic insults. Little is known about the genes involved in mitochondrial adaptation to the buildup of chronic stress. Using combinations of genetic manipulations and stress for analyzing structural, transcriptional, mitochondrial, and behavioral outcomes, we characterized NR4A1 as a stress-inducible modifier of mitochondrial energetic competence and dendritic spine number in PFC. NR4A1 acted as a transcription factor for changing the expression of target genes previously involved in mitochondrial uncoupling, AMP-activated protein kinase activation, and synaptic growth. Maintenance of NR4A1 activity by chronic stress played a critical role in the regressive synaptic organization in PFC of mouse models of stress (male only). Knockdown, dominant-negative approach, and knockout of Nr4a1 in mice and rats (male only) protected pyramidal neurons against the adverse effects of chronic stress. In human PFC tissues of men and women, high levels of the transcriptionally active NR4A1 correlated with measures of synaptic loss and cognitive impairment. In the context of chronic stress, prolonged expression and activity of NR4A1 may lead to responses of mitochondria and synaptic connectivity that do not match environmental demand, resulting in circuit malfunction between PFC and other brain regions, constituting a pathological feature across disorders. SIGNIFICANCE STATEMENT The bioenergetic cost of chronic stress is too high to be sustainable by pyramidal prefrontal neurons. Cellular checkpoints have evolved to adjust the responses of mitochondria and synapses to the buildup of chronic stress. NR4A1 plays such a role by controlling the energetic competence of mitochondria with respect to synapse number. As an immediate-early gene, Nr4a1 promotes neuronal plasticity, but sustained expression or activity can be detrimental. NR4A1 expression and activity is sustained by chronic stress in animal models and in human studies of neuropathologies sensitive to the buildup of chronic stress. Therefore, antagonism of NR4A1 is a promising avenue for preventing the regressive synaptic reorganization in cortical systems in the context of chronic stress.
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Ahmad F, Salahuddin M, Alamoudi W, Acharya S. Dysfunction of cortical synapse-specific mitochondria in developing rats exposed to lead and its amelioration by ascorbate supplementation. Neuropsychiatr Dis Treat 2018; 14:813-824. [PMID: 29606875 PMCID: PMC5868605 DOI: 10.2147/ndt.s148248] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Lead (Pb) is a widespread environmental neurotoxin and its exposure even in minute quantities can lead to compromised neuronal functions. A developing brain is particularly vulnerable to Pb mediated toxicity and early-life exposure leads to permanent alterations in brain development and neuronal signaling and plasticity, culminating into cognitive and behavioral dysfunctions and elevated risk of neuropsychiatric disorders later in life. Nevertheless, the underlying biochemical mechanisms have not been completely discerned. METHODS Because of their ability to fulfill high energy needs and to act as calcium buffers in events of high intensity neuronal activity as well as their adaptive regulatory capability to match the requirements of the dynamicity of synaptic signaling, synapse-specific or synaptic mitochondria (SM) are critical for synaptic development, function and plasticity. Our aim for the present study hence was to characterize the effects of early-life Pb exposure on the functions of SM of prepubertal rats. For this purpose, employing a chronic model of Pb neurotoxicity, we exposed rat pups perinatally and postnatally to Pb and used a plethora of colorimetric and fluorometric assays for assessing redox and bioenergetic properties of SM. In addition, taking advantage of its ability as an antioxidant and as a metal chelator, we employed ascorbic acid (vitamin C) supplementation as an ameliorative therapeutic strategy against Pb-induced neurotoxicity and dysfunction of SM. RESULTS Our results suggest that early-life exposure to Pb leads to elevated oxidative stress in cortical SM with consequent compromises in its energy metabolism activity. Ascorbate supplementation resulted in significant recovery of Pb-induced oxidative stress and functional compromise of SM. CONCLUSION Alterations in redox status and bioenergetic properties of SM could potentially contribute to the synaptic dysfunction observed in events of Pb neurotoxicity. Additionally, our study provides evidence for suitability of ascorbate as a significant ameliorative agent in tacking Pb neurotoxicity.
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Affiliation(s)
- Faraz Ahmad
- Department of Public Health, College of Public Health, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia.,Neuroscience Department, Institute for Research and Medical Consultations, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Mohammad Salahuddin
- Animal House Department, Institute for Research and Medical Consultations, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Widyan Alamoudi
- Neuroscience Department, Institute for Research and Medical Consultations, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Sadananda Acharya
- Department of Public Health, College of Public Health, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
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Puighermanal E, Biever A, Pascoli V, Melser S, Pratlong M, Cutando L, Rialle S, Severac D, Boubaker-Vitre J, Meyuhas O, Marsicano G, Lüscher C, Valjent E. Ribosomal Protein S6 Phosphorylation Is Involved in Novelty-Induced Locomotion, Synaptic Plasticity and mRNA Translation. Front Mol Neurosci 2017; 10:419. [PMID: 29311811 PMCID: PMC5742586 DOI: 10.3389/fnmol.2017.00419] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 12/01/2017] [Indexed: 11/29/2022] Open
Abstract
The phosphorylation of the ribosomal protein S6 (rpS6) is widely used to track neuronal activity. Although it is generally assumed that rpS6 phosphorylation has a stimulatory effect on global protein synthesis in neurons, its exact biological function remains unknown. By using a phospho-deficient rpS6 knockin mouse model, we directly tested the role of phospho-rpS6 in mRNA translation, plasticity and behavior. The analysis of multiple brain areas shows for the first time that, in neurons, phospho-rpS6 is dispensable for overall protein synthesis. Instead, we found that phospho-rpS6 controls the translation of a subset of mRNAs in a specific brain region, the nucleus accumbens (Acb), but not in the dorsal striatum. We further show that rpS6 phospho-mutant mice display altered long-term potentiation (LTP) in the Acb and enhanced novelty-induced locomotion. Collectively, our findings suggest a previously unappreciated role of phospho-rpS6 in the physiology of the Acb, through the translation of a selective subclass of mRNAs, rather than the regulation of general protein synthesis.
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Affiliation(s)
| | - Anne Biever
- IGF, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Vincent Pascoli
- Department of Basic Neurosciences, Medical Faculty, University of Geneva, Geneva, Switzerland
| | - Su Melser
- INSERM U1215, Université de Bordeaux, NeuroCentre Magendie, Bordeaux, France
| | - Marine Pratlong
- Montpellier GenomiX, BioCampus Montpellier, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Laura Cutando
- IGF, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Stephanie Rialle
- Montpellier GenomiX, BioCampus Montpellier, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Dany Severac
- Montpellier GenomiX, BioCampus Montpellier, CNRS, INSERM, University of Montpellier, Montpellier, France
| | | | - Oded Meyuhas
- Department of Biochemistry and Molecular Biology, IMRIC, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Giovanni Marsicano
- INSERM U1215, Université de Bordeaux, NeuroCentre Magendie, Bordeaux, France
| | - Christian Lüscher
- Department of Basic Neurosciences, Medical Faculty, University of Geneva, Geneva, Switzerland.,Clinic of Neurology, Department of Clinical Neurosciences, Geneva University Hospital, Geneva, Switzerland
| | - Emmanuel Valjent
- IGF, CNRS, INSERM, University of Montpellier, Montpellier, France
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Chen F, Ardalan M, Elfving B, Wegener G, Madsen TM, Nyengaard JR. Mitochondria Are Critical for BDNF-Mediated Synaptic and Vascular Plasticity of Hippocampus following Repeated Electroconvulsive Seizures. Int J Neuropsychopharmacol 2017; 21:291-304. [PMID: 29228215 PMCID: PMC5838811 DOI: 10.1093/ijnp/pyx115] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 12/05/2017] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Electroconvulsive therapy is a fast-acting and efficient treatment of depression used in the clinic. The underlying mechanism of its therapeutic effect is still unclear. However, recovery of synaptic connections and synaptic remodeling is thought to play a critical role for the clinical efficacy obtained from a rapid antidepressant response. Here, we investigated the relationship between synaptic changes and concomitant nonneuronal changes in microvasculature and mitochondria and its relationship to brain-derived neurotrophic factor level changes after repeated electroconvulsive seizures, an animal model of electroconvulsive therapy. METHODS Electroconvulsive seizures or sham treatment was given daily for 10 days to rats displaying a genetically driven phenotype modelling clinical depression: the Flinders Sensitive and Resistant Line rats. Stereological principles were employed to quantify numbers of synapses and mitochondria, and the length of microvessels in the hippocampus. The brain-derived neurotrophic factor protein levels were quantified with immunohistochemistry. RESULTS In untreated controls, a lower number of synapses and mitochondria was accompanied by shorter microvessels of the hippocampus in "depressive" phenotype (Flinders Sensitive Line) compared with the "nondepressed" phenotype (Flinders Resistant Line). Electroconvulsive seizure administration significantly increased the number of synapses and mitochondria, and length of microvessels both in Flinders Sensitive Line-electroconvulsive seizures and Flinders Resistant Line-electroconvulsive seizures rats. In addition, the amount of brain-derived neurotrophic factor protein was significantly increased in Flinders Sensitive Line and Flinders Resistant Line rats after electroconvulsive seizures. Furthermore, there was a significant positive correlation between brain-derived neurotrophic factor level and mitochondria/synapses. CONCLUSION Our results indicate that rapid and efficient therapeutic effect of electroconvulsive seizures may be related to synaptic plasticity, accompanied by brain-derived neurotrophic factor protein level elevation and mitochondrial and vascular support.
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Affiliation(s)
- Fenghua Chen
- Core Center for Molecular Morphology, Section for Stereology and Microscopy, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark,Correspondence: Fenghua Chen, MD, PhD, Department of Clinical Medicine, Translational Neuropsychiatry Unit, Skovagervej 2, building 14K, 0.15, 8240 Risskov, Denmark ()
| | - Maryam Ardalan
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Risskov, Denmark,Center of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom, South Africa,Department of Clinical Medicine, Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| | - Betina Elfving
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Risskov, Denmark
| | - Gregers Wegener
- AUGUST Centre, Department of Clinical Medicine, Aarhus University, Risskov, Denmark
| | | | - Jens R Nyengaard
- Core Center for Molecular Morphology, Section for Stereology and Microscopy, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark,Centre for Stochastic Geometry and Advanced Bioimaging, Aarhus University, Aarhus, Denmark
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Abstract
Most of the energy we get to spend is furnished by mitochondria, minuscule living structures sitting inside our cells or dispatched back and forth within them to where they are needed. Mitochondria produce energy by burning down what remains of our meal after we have digested it, but at the cost of constantly corroding themselves and us. Here we review how our mitochondria evolved from invading bacteria and have retained a small amount of independence from us; how we inherit them only from our mother; and how they are heavily implicated in learning, memory, cognition, and virtually every mental or neurological affliction. We discuss why counteracting mitochondrial corrosion with antioxidant supplements is often unwise, and why our mitochondria, and therefore we ourselves, benefit instead from exercise, meditation, sleep, sunshine, and particular eating habits. Finally, we describe how malfunctioning mitochondria force rats to become socially subordinate to others, how such disparity can be evened off by a vitamin, and why these findings are relevant to us.
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Affiliation(s)
- Peter Kramer
- Department of General Psychology, University of Padua, Italy
| | - Paola Bressan
- Department of General Psychology, University of Padua, Italy
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42
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Chronic Stress Causes Sex-Specific and Structure-Specific Alterations in Mitochondrial Respiratory Chain Activity in Rat Brain. Neurochem Res 2017; 42:3331-3340. [DOI: 10.1007/s11064-017-2375-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 07/28/2017] [Accepted: 08/03/2017] [Indexed: 10/18/2022]
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Abstract
Glucocorticoids via the glucocorticoid receptor (GR) have effects on a variety of cell types, eliciting important physiological responses via changes in gene expression and signaling. Although decades of research have illuminated the mechanism of how this important steroid receptor controls gene expression using
in vitro and cell culture–based approaches, how GR responds to changes in external signals
in vivo under normal and pathological conditions remains elusive. The goal of this review is to highlight recent work on GR action in fat cells and liver to affect metabolism
in vivo and the role GR ligands and receptor phosphorylation play in calibrating signaling outputs by GR in the brain in health and disease. We also suggest that both the brain and fat tissue communicate to affect physiology and behavior and that understanding this “brain-fat axis” will enable a more complete understanding of metabolic diseases and inform new ways to target them.
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Affiliation(s)
- Michael J Garabedian
- Department of Microbiology, New York University School of Medicine, Alexandria Center for Life Sciences, 450 East 29th Street, Room 324, New York, NY, 10016, USA
| | - Charles A Harris
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Freddy Jeanneteau
- Departments of Physiology and Neuroscience, Institute of Functional Genomics, INSERM U1191, CNRS UMR5203, University of Montpellier, 34094 Montpellier, France
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Lacourt TE, Heijnen CJ. Mechanisms of Neurotoxic Symptoms as a Result of Breast Cancer and Its Treatment: Considerations on the Contribution of Stress, Inflammation, and Cellular Bioenergetics. CURRENT BREAST CANCER REPORTS 2017; 9:70-81. [PMID: 28616125 PMCID: PMC5445149 DOI: 10.1007/s12609-017-0245-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
PURPOSE OF REVIEW Breast cancer and its treatment are associated with a range of neurotoxic symptoms, such as fatigue, cognitive impairment, and pain. Although these symptoms generally subside after treatment completion, they become chronic in a significant subset of patients. We here summarize recent findings on neuroinflammation, stress, and mitochondrial dysfunction as mechanistic pathways leading to neurotoxic symptom experience in breast cancer patients and survivors. RECENT FINDINGS Neuroinflammation related to stress or cancer treatment and stress resulting from diagnosis, treatment, or (cancer-related) worrying are important predictors of a neurotoxic symptom experience, both during and after treatment for breast cancer. Both inflammation and stress hormones, as well as cancer treatment, can induce mitochondrial dysfunction resulting in reduced cellular energy. SUMMARY We propose reduced cellular energy (mitochondrial dysfunction) induced by inflammation, oxygen radical production, and stress as a result of cancer and/or cancer treatment as a final mechanism underlying neurotoxic symptoms.
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Affiliation(s)
- Tamara E. Lacourt
- Department of Symptom Research, Neuroimmunology Laboratory, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Unit 384, Houston, TX 77030 USA
| | - Cobi J. Heijnen
- Department of Symptom Research, Neuroimmunology Laboratory, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Unit 384, Houston, TX 77030 USA
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Tissue Type-Specific Bioenergetic Abnormalities in Adults with Major Depression. Neuropsychopharmacology 2017; 42:876-885. [PMID: 27585738 PMCID: PMC5312061 DOI: 10.1038/npp.2016.180] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 08/11/2016] [Accepted: 08/27/2016] [Indexed: 11/08/2022]
Abstract
Brain bioenergetic abnormalities have been observed frequently in adults with major depressive disorder (MDD); however, results have been inconsistent regarding whether decreased or increased metabolism was observed. Phosphorus-31 magnetic resonance spectroscopy (31P MRS) allows for the quantification of bioenergetic molecules, containing high-energy phosphates, over the whole brain as well as measuring the differences between gray matter and white matter. We recruited 50 subjects with a current diagnosis of MDD, not currently treated with psychotropic medication, between ages of 18 and 65 (mean±SD age: 43.4±13.6; 46% female) and 30 healthy volunteers, matched for age and gender (39.0±12.5 years of age; 36.6% female). All subjects received a T1 MP-FLASH scan for tissue segmentation followed by 31P MRS, chemical shift imaging scan with 84 voxels of data collected over the entire brain utilizing a dual-tuned, proton-phosphorus coil to minimize subject movement. Phosphocreatine and inorganic phosphate (Pi) varied in opposite directions across gray matter and white matter when MDD subjects were compared with controls. This finding suggests alterations in high-energy phosphate metabolism and regulation of oxidative phosphorylation in MDD patients. In addition, within the MDD group, gray matter Pi, a regulator of oxidative phosphorylation, correlated positively with severity of depression. These data support a model that includes changes in brain bioenergetic function in subjects with major depression.
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Deletion of Neurotrophin Signaling through the Glucocorticoid Receptor Pathway Causes Tau Neuropathology. Sci Rep 2016; 6:37231. [PMID: 27849045 PMCID: PMC5110980 DOI: 10.1038/srep37231] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 10/26/2016] [Indexed: 01/29/2023] Open
Abstract
Glucocorticoid resistance is a risk factor for Alzheimer's disease (AD). Molecular and cellular mechanisms of glucocorticoid resistance in the brain have remained unknown and are potential therapeutic targets. Phosphorylation of glucocorticoid receptors (GR) by brain-derived neurotrophic factor (BDNF) signaling integrates both pathways for remodeling synaptic structure and plasticity. The goal of this study is to test the role of the BDNF-dependent pathway on glucocorticoid signaling in a mouse model of glucocorticoid resistance. We report that deletion of GR phosphorylation at BDNF-responding sites and downstream signaling via the MAPK-phosphatase DUSP1 triggers tau phosphorylation and dendritic spine atrophy in mouse cortex. In human cortex, DUSP1 protein expression correlates with tau phosphorylation, synaptic defects and cognitive decline in subjects diagnosed with AD. These findings provide evidence for a causal role of BDNF-dependent GR signaling in tau neuropathology and indicate that DUSP1 is a potential target for therapeutic interventions.
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Attention deficit-hyperactivity disorder suffers from mitochondrial dysfunction. BBA CLINICAL 2016; 6:153-158. [PMID: 27896136 PMCID: PMC5121149 DOI: 10.1016/j.bbacli.2016.10.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 10/17/2016] [Indexed: 12/23/2022]
Abstract
Background Pathophysiology of attention-deficit hyperactivity disorder (ADHD) is not known, and therefore the present study investigated mitochondrial defects, if any in cybrids created from patients and control population. Methods To investigate mitochondrial pathology in ADHD, cybrids cell lines were created from ADHD probands and controls by fusing their platelets with ρ0-cells prepared from SH-SY5Y neuroblastoma cell line. Cellular respiration, oxidative stress, mitochondrial membrane potential and morphology were evaluated employing oxygraph, mitochondria-specific fluorescence staining and evaluation by FACS, and immunocytochemistry. HPLC-electrochemical detection, quantitative RT-PCR and Blue Native PAGE were employed respectively for assays of serotonin, mitochondrial ATPase 6/8 subunits levels and complex V activity. Results Significantly low cellular and mitochondrial respiration, ATPase6/8 transcripts levels, mitochondrial complex V activity and loss of mitochondrial membrane potential and elevated oxidative stress were observed in ADHD cybrids. Expression of monoamine oxidizing mitochondrial enzymes, MAO-A and MAO-B levels remained unaffected. Two-fold increase in serotonin level was noted in differentiated cybrid-neurons. Conclusions Since cybrids are shown to replicate mitochondrial defects seen in post-mortem brains, these observed defects in ADHD cybrids strongly suggest mitochondrial pathology in this disorder. General significance Mitochondrial defects are detected in ADHD cybrids created from patients' platelets, implying bioenergetics crisis in the mitochondria could be a contributory factor for ADHD pathology and/or phenotypes.
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