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Horvat A, Vlašić I, Štefulj J, Oršolić N, Jazvinšćak Jembrek M. Flavonols as a Potential Pharmacological Intervention for Alleviating Cognitive Decline in Diabetes: Evidence from Preclinical Studies. Life (Basel) 2023; 13:2291. [PMID: 38137892 PMCID: PMC10744738 DOI: 10.3390/life13122291] [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: 09/30/2023] [Revised: 11/15/2023] [Accepted: 11/24/2023] [Indexed: 12/24/2023] Open
Abstract
Diabetes mellitus is a complex metabolic disease associated with reduced synaptic plasticity, atrophy of the hippocampus, and cognitive decline. Cognitive impairment results from several pathological mechanisms, including increased levels of advanced glycation end products (AGEs) and their receptors, prolonged oxidative stress and impaired activity of endogenous mechanisms of antioxidant defense, neuroinflammation driven by the nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB), decreased expression of brain-derived neurotrophic factor (BDNF), and disturbance of signaling pathways involved in neuronal survival and cognitive functioning. There is increasing evidence that dietary interventions can reduce the risk of various diabetic complications. In this context, flavonols, a highly abundant class of flavonoids in the human diet, are appreciated as a potential pharmacological intervention against cognitive decline in diabetes. In preclinical studies, flavonols have shown neuroprotective, antioxidative, anti-inflammatory, and memory-enhancing properties based on their ability to regulate glucose levels, attenuate oxidative stress and inflammation, promote the expression of neurotrophic factors, and regulate signaling pathways. The present review gives an overview of the molecular mechanisms involved in diabetes-induced cognitive dysfunctions and the results of preclinical studies showing that flavonols have the ability to alleviate cognitive impairment. Although the results from animal studies are promising, clinical and epidemiological studies are still needed to advance our knowledge on the potential of flavonols to improve cognitive decline in diabetic patients.
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Affiliation(s)
- Anđela Horvat
- Division of Molecular Medicine, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Ignacija Vlašić
- Division of Molecular Medicine, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
| | - Jasminka Štefulj
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
- Department of Psychology, Catholic University of Croatia, Ilica 242, 10000 Zagreb, Croatia
| | - Nada Oršolić
- Division of Animal Physiology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, 10000 Zagreb, Croatia
| | - Maja Jazvinšćak Jembrek
- Division of Molecular Medicine, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia
- Department of Psychology, Catholic University of Croatia, Ilica 242, 10000 Zagreb, Croatia
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2
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Apio C, Chung W, Moon MK, Kwon O, Park T. Gene-diet interaction analysis using novel weighted food scores discovers the adipocytokine signaling pathway associated with the development of type 2 diabetes. Front Endocrinol (Lausanne) 2023; 14:1165744. [PMID: 37680885 PMCID: PMC10482093 DOI: 10.3389/fendo.2023.1165744] [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: 02/14/2023] [Accepted: 07/31/2023] [Indexed: 09/09/2023] Open
Abstract
Introduction The influence of dietary patterns measured using Recommended Food Score (RFS) with foods with high amounts of antioxidant nutrients for Type 2 diabetes (T2D) was analyzed. Our analysis aims to find associations between dietary patterns and T2D and conduct a gene-diet interaction analysis related to T2D. Methods Data analyzed in the current study were obtained from the Korean Genome and Epidemiology Study Cohort. The dietary patterns of 46 food items were assessed using a validated food frequency questionnaire. To maximize the predictive power of the RFS, we propose two weighted food scores, namely HisCoM-RFS calculated using the novel Hierarchical Structural Component model (HisCoM) and PLSDA-RFS calculated using Partial Least Squares-Discriminant Analysis (PLS-DA) method. Results Both RFS (OR: 1.11; 95% CI: 1.03- 1.20; P = 0.009) and PLSDA-RFS (OR: 1.10; 95% CI: 1.02-1.19, P = 0.011) were positively associated with T2D. Mapping of SNPs (P < 0.05) from the interaction analysis between SNPs and the food scores to genes and pathways yielded some 12 genes (CACNA2D3, RELN, DOCK2, SLIT3, CTNNA2, etc.) and pathways associated with T2D. The strongest association was observed with the adipocytokine signalling pathway, highlighting 32 genes (STAT3, MAPK10, MAPK8, IRS1, AKT1-3, ADIPOR2, etc.) most likely associated with T2D. Finally, the group of the subjects in low, intermediate and high using both the food scores and a polygenic risk score found an association between diet quality groups with issues at high genetic risk of T2D. Conclusion A dietary pattern of poor amounts of antioxidant nutrients is associated with the risk of T2D, and diet affects pathway mechanisms involved in developing T2D.
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Affiliation(s)
- Catherine Apio
- Interdisciplinary Program in Bioinformatics, Seoul National University, Seoul, Republic of Korea
| | - Wonil Chung
- Department of Statistics and Actuarial Science, Soongsil University, Seoul, Republic of Korea
| | - Min Kyong Moon
- Department of Internal Medicine, College of Medicine, Seoul National University, Seoul, Republic of Korea
| | - Oran Kwon
- Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, Republic of Korea
| | - Taesung Park
- Department of Statistics, Seoul National University, Seoul, Republic of Korea
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3
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Leung A, Rangamani P. Computational modeling of AMPK and mTOR crosstalk in glutamatergic synapse calcium signaling. NPJ Syst Biol Appl 2023; 9:34. [PMID: 37460570 DOI: 10.1038/s41540-023-00295-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 06/29/2023] [Indexed: 07/20/2023] Open
Abstract
Neuronal energy consumption is vital for information processing and memory formation in synapses. The brain consists of just 2% of the human body's mass, but consumes almost 20% of the body's energy budget. Most of this energy is attributed to active transport in ion signaling, with calcium being the canonical second messenger of synaptic transmission. Here, we develop a computational model of synaptic signaling resulting in the activation of two protein kinases critical in metabolic regulation and cell fate, AMP-Activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) and investigate the effect of glutamate stimulus frequency on their dynamics. Our model predicts that frequencies of glutamate stimulus over 10 Hz perturb AMPK and mTOR oscillations at higher magnitudes by up to 36% and change the area under curve (AUC) by 5%. This dynamic difference in AMPK and mTOR activation trajectories potentially differentiates high frequency stimulus bursts from basal neuronal signaling leading to a downstream change in synaptic plasticity. Further, we also investigate the crosstalk between insulin receptor and calcium signaling on AMPK and mTOR activation and predict that the pathways demonstrate multistability dependent on strength of insulin signaling and metabolic consumption rate. Our predictions have implications for improving our understanding of neuronal metabolism, synaptic pruning, and synaptic plasticity.
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Affiliation(s)
- A Leung
- Chemical Engineering Graduate Program, University of California San Diego, La Jolla, CA, USA
| | - P Rangamani
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA, USA.
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4
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Kelty TJ, Dashek RJ, Arnold WD, Rector RS. Emerging Links between Nonalcoholic Fatty Liver Disease and Neurodegeneration. Semin Liver Dis 2023; 43:77-88. [PMID: 36764305 DOI: 10.1055/s-0043-1762585] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
The association between liver and brain health has gained attention as biomarkers of liver function have been revealed to predict neurodegeneration. The liver is a central regulator in metabolic homeostasis. However, in nonalcoholic fatty liver disease (NAFLD), homeostasis is disrupted which can result in extrahepatic organ pathologies. Emerging literature provides insight into the mechanisms behind the liver-brain health axis. These include the increased production of liver-derived factors that promote insulin resistance and loss of neuroprotective factors under conditions of NAFLD that increase insulin resistance in the central nervous system. In addition, elevated proinflammatory cytokines linked to NAFLD negatively impact the blood-brain barrier and increase neuroinflammation. Furthermore, exacerbated dyslipidemia associated with NAFLD and hepatic dysfunction can promote altered brain bioenergetics and oxidative stress. In this review, we summarize the current knowledge of the crosstalk between liver and brain as it relates to the pathophysiology between NAFLD and neurodegeneration, with an emphasis on Alzheimer's disease. We also highlight knowledge gaps and future areas for investigation to strengthen the potential link between NAFLD and neurodegeneration.
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Affiliation(s)
- Taylor J Kelty
- Department of Biomedical Sciences, University of Missouri - Columbia, Columbia, Missouri
- Department of Nutrition and Exercise Physiology, University of Missouri - Columbia, Columbia, Missouri
- NextGen Precision Health, University of Missouri - Columbia, Columbia, Missouri
| | - Ryan J Dashek
- Department of Biomedical Sciences, University of Missouri - Columbia, Columbia, Missouri
- NextGen Precision Health, University of Missouri - Columbia, Columbia, Missouri
- Comparative Medicine Program, University of Missouri - Columbia, Columbia, Missouri
| | - W David Arnold
- NextGen Precision Health, University of Missouri - Columbia, Columbia, Missouri
- Physical Medicine and Rehabilitation, University of Missouri - Columbia, Columbia, Missouri
| | - R Scott Rector
- Department of Nutrition and Exercise Physiology, University of Missouri - Columbia, Columbia, Missouri
- NextGen Precision Health, University of Missouri - Columbia, Columbia, Missouri
- Research Service, Harry S. Truman Memorial Veterans' Hospital, Columbia, Missouri
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Missouri - Columbia, Columbia, Missouri
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5
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Fan X, Xia L, Zhou Z, Qiu Y, Zhao C, Yin X, Qian W. Tau Acts in Concert With Kinase/Phosphatase Underlying Synaptic Dysfunction. Front Aging Neurosci 2022; 14:908881. [PMID: 35711910 PMCID: PMC9196307 DOI: 10.3389/fnagi.2022.908881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 04/28/2022] [Indexed: 11/24/2022] Open
Abstract
Alzheimer's disease (AD) is characterized by two pathological features: neurofibrillary tangles (NFTs), formed by microtubule-associated protein tau, and abnormal accumulation of amyloid-β (Aβ). Multiple evidence placed synaptic tau as the vital fact of AD pathology, especially at the very early stage of AD. In the present review, we discuss tau phosphorylation, which is critical for the dendritic localization of tau and synaptic plasticity. We review the related kinases and phosphatases implicated in the synaptic function of tau. We also review the synergistic effects of these kinases and phosphatases on tau-associated synaptic deficits. We aim to open a new perspective on the treatment of AD.
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Affiliation(s)
- Xing Fan
- Department of Biochemistry and Molecular Biology, Medical School, Jiangsu Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Liye Xia
- Department of Biochemistry and Molecular Biology, Medical School, Jiangsu Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Zheng Zhou
- Department of Biochemistry and Molecular Biology, Medical School, Jiangsu Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Yanyan Qiu
- Department of Biochemistry and Molecular Biology, Medical School, Jiangsu Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Chenhao Zhao
- Department of Biochemistry and Molecular Biology, Medical School, Jiangsu Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Xiaomin Yin
- Department of Biochemistry and Molecular Biology, Medical School, Jiangsu Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
- NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Wei Qian
- Department of Biochemistry and Molecular Biology, Medical School, Jiangsu Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education of China, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
- NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
- *Correspondence: Wei Qian
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Cheng D, Yang S, Zhao X, Wang G. The Role of Glucagon-Like Peptide-1 Receptor Agonists (GLP-1 RA) in Diabetes-Related Neurodegenerative Diseases. Drug Des Devel Ther 2022; 16:665-684. [PMID: 35340338 PMCID: PMC8943601 DOI: 10.2147/dddt.s348055] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 02/18/2022] [Indexed: 12/17/2022] Open
Abstract
Recent clinical guidelines have emphasized the importance of screening for cognitive impairment in older adults with diabetes, however, there is still a lack of understanding about the drug therapy. Glucagon-like peptide 1 receptor agonists (GLP-1 RAs) are widely used in the treatment of type 2 diabetes and potential applications may include the treatment of obesity as well as the adjunctive treatment of type 1 diabetes mellitus in combination with insulin. Growing evidence suggests that GLP-1 RA has the potential to treat neurodegenerative diseases, particularly in diabetes-related Alzheimer’s disease (AD) and Parkinson’s disease (PD). Here, we review the molecular mechanisms of the neuroprotective effects of GLP-1 RA in diabetes-related degenerative diseases, including AD and PD, and their potential effects.
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Affiliation(s)
- Dihe Cheng
- Department of Endocrinology and Metabolism, The First Hospital of Jilin University, Changchun, 130021, People's Republic of China
| | - Shuo Yang
- Department of Endocrinology and Metabolism, The First Hospital of Jilin University, Changchun, 130021, People's Republic of China
| | - Xue Zhao
- Department of Endocrinology and Metabolism, The First Hospital of Jilin University, Changchun, 130021, People's Republic of China
| | - Guixia Wang
- Department of Endocrinology and Metabolism, The First Hospital of Jilin University, Changchun, 130021, People's Republic of China
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Dysmetabolism and Neurodegeneration: Trick or Treat? Nutrients 2022; 14:nu14071425. [PMID: 35406040 PMCID: PMC9003269 DOI: 10.3390/nu14071425] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/24/2022] [Accepted: 03/25/2022] [Indexed: 02/06/2023] Open
Abstract
Accumulating evidence suggests the existence of a strong link between metabolic syndrome and neurodegeneration. Indeed, epidemiologic studies have described solid associations between metabolic syndrome and neurodegeneration, whereas animal models contributed for the clarification of the mechanistic underlying the complex relationships between these conditions, having the development of an insulin resistance state a pivotal role in this relationship. Herein, we review in a concise manner the association between metabolic syndrome and neurodegeneration. We start by providing concepts regarding the role of insulin and insulin signaling pathways as well as the pathophysiological mechanisms that are in the genesis of metabolic diseases. Then, we focus on the role of insulin in the brain, with special attention to its function in the regulation of brain glucose metabolism, feeding, and cognition. Moreover, we extensively report on the association between neurodegeneration and metabolic diseases, with a particular emphasis on the evidence observed in animal models of dysmetabolism induced by hypercaloric diets. We also debate on strategies to prevent and/or delay neurodegeneration through the normalization of whole-body glucose homeostasis, particularly via the modulation of the carotid bodies, organs known to be key in connecting the periphery with the brain.
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8
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Research Progress on Neuroprotection of Insulin-like Growth Factor-1 towards Glutamate-Induced Neurotoxicity. Cells 2022; 11:cells11040666. [PMID: 35203315 PMCID: PMC8870287 DOI: 10.3390/cells11040666] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2021] [Revised: 02/05/2022] [Accepted: 02/11/2022] [Indexed: 02/01/2023] Open
Abstract
Insulin-like growth factor-1 (IGF-1) and its binding proteins and receptors are widely expressed in the central nervous system (CNS), proposing IGF-1-induced neurotrophic actions in normal growth, development, and maintenance. However, while there is convincing evidence that the IGF-1 system has specific endocrine roles in the CNS, the concept is emerging that IGF-I might be also important in disorders such as ischemic stroke, brain trauma, Alzheimer’s disease, epilepsy, etc., by inducing neuroprotective effects towards glutamate-mediated excitotoxic signaling pathways. Research in rodent models has demonstrated rescue of pathophysiological and behavioral abnormalities when IGF-1 was administered by different routes, and several clinical studies have shown safety and promise of efficacy in neurological disorders of the CNS. Focusing on the relationship between IGF-1-induced neuroprotection and glutamate-induced excitatory neurotoxicity, this review addresses the research progress in the field, intending to provide a rationale for using IGF-I clinically to confer neuroprotective therapy towards neurological diseases with glutamate excitotoxicity as a common pathological pathway.
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9
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Williams HC, Carlson SW, Saatman KE. A role for insulin-like growth factor-1 in hippocampal plasticity following traumatic brain injury. VITAMINS AND HORMONES 2022; 118:423-455. [PMID: 35180936 DOI: 10.1016/bs.vh.2021.11.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Traumatic brain injury (TBI) initiates a constellation of secondary injury cascades, leading to neuronal damage and dysfunction that is often beyond the scope of endogenous repair mechanisms. Cognitive deficits are among the most persistent morbidities resulting from TBI, necessitating a greater understanding of mechanisms of posttraumatic hippocampal damage and neuroplasticity and identification of therapies that improve recovery by enhancing repair pathways. Focusing here on hippocampal neuropathology associated with contusion-type TBIs, the impact of brain trauma on synaptic structure and function and the process of adult neurogenesis is discussed, reviewing initial patterns of damage as well as evidence for spontaneous recovery. A case is made that insulin-like growth factor-1 (IGF-1), a growth-promoting peptide synthesized in both the brain and the periphery, is well suited to augment neuroplasticity in the injured brain. Essential during brain development, multiple lines of evidence delineate roles in the adult brain for IGF-1 in the maintenance of synapses, regulation of neurotransmission, and modulation of forms of synaptic plasticity such as long-term potentiation. Further, IGF-1 enhances adult hippocampal neurogenesis though effects on proliferation and neuronal differentiation of neural progenitor cells and on dendritic growth of newly born neurons. Post-injury administration of IGF-1 has been effective in rodent models of TBI in improving learning and memory, attenuating death of mature hippocampal neurons and promoting neurogenesis, providing critical proof-of-concept data. More studies are needed to explore the effects of IGF-1-based therapies on synaptogenesis and synaptic plasticity following TBI and to optimize strategies in order to stimulate only appropriate, functional neuroplasticity.
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Affiliation(s)
- Hannah C Williams
- Spinal Cord and Brain Injury Research Center, Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Shaun W Carlson
- Department of Neurological Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Kathryn E Saatman
- Spinal Cord and Brain Injury Research Center, Department of Physiology, University of Kentucky, Lexington, KY, United States.
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10
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Takayanagi Y, Ishizuka K, Laursen TM, Yukitake H, Yang K, Cascella NG, Ueda S, Sumitomo A, Narita Z, Horiuchi Y, Niwa M, Taguchi A, White MF, Eaton WW, Mortensen PB, Sakurai T, Sawa A. From population to neuron: exploring common mediators for metabolic problems and mental illnesses. Mol Psychiatry 2021; 26:3931-3942. [PMID: 33173197 PMCID: PMC8514126 DOI: 10.1038/s41380-020-00939-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 10/05/2020] [Accepted: 10/26/2020] [Indexed: 11/24/2022]
Abstract
Major mental illnesses such as schizophrenia (SZ) and bipolar disorder (BP) frequently accompany metabolic conditions, but their relationship is still unclear, in particular at the mechanistic level. We implemented an approach of "from population to neuron", combining population-based epidemiological analysis with neurobiological experiments using cell and animal models based on a hypothesis built from the epidemiological study. We characterized high-quality population data, olfactory neuronal cells biopsied from patients with SZ or BP, and healthy subjects, as well as mice genetically modified for insulin signaling. We accessed the Danish Registry and observed (1) a higher incidence of diabetes in people with SZ or BP and (2) higher incidence of major mental illnesses in people with diabetes in the same large cohort. These epidemiological data suggest the existence of common pathophysiological mediators in both diabetes and major mental illnesses. We hypothesized that molecules associated with insulin resistance might be such common mediators, and then validated the hypothesis by using two independent sets of olfactory neuronal cells biopsied from patients and healthy controls. In the first set, we confirmed an enrichment of insulin signaling-associated molecules among the genes that were significantly different between SZ patients and controls in unbiased expression profiling data. In the second set, olfactory neuronal cells from SZ and BP patients who were not pre-diabetic or diabetic showed reduced IRS2 tyrosine phosphorylation upon insulin stimulation, indicative of insulin resistance. These cells also displayed an upregulation of IRS1 protein phosphorylation at serine-312 at baseline (without insulin stimulation), further supporting the concept of insulin resistance in olfactory neuronal cells from SZ patients. Finally, Irs2 knockout mice showed an aberrant response to amphetamine, which is also observed in some patients with major mental illnesses. The bi-directional relationships between major mental illnesses and diabetes suggest that there may be common pathophysiological mediators associated with insulin resistance underlying these mental and physical conditions.
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Affiliation(s)
- Yoichiro Takayanagi
- Department of Mental Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA
| | - Koko Ishizuka
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Thomas M. Laursen
- National Centre for Register-Based Research, Department of Economics and Business Economics, Aarhus University, Denmark
| | - Hiroshi Yukitake
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kun Yang
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Nicola G. Cascella
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Shuhei Ueda
- Medical Innovation Center, Kyoto University Graduate School of Medicine, Japan
| | - Akiko Sumitomo
- Medical Innovation Center, Kyoto University Graduate School of Medicine, Japan
| | - Zui Narita
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yasue Horiuchi
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Minae Niwa
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Akiko Taguchi
- Department of Integrative Aging Neuroscience, National Center for Geriatrics and Gerontology, Japan
| | - Morris F. White
- Division of Endocrinology, Department of Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - William W. Eaton
- Department of Mental Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA
| | - Preben B. Mortensen
- National Centre for Register-Based Research, Department of Economics and Business Economics, Aarhus University, Denmark,The Lundbeck Foundation’s Initiative for Integrative Research, iPSYCH,Center for Integrated Register-based Research at Aarhus University, CIRRAU, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Takeshi Sakurai
- Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan.
| | - Akira Sawa
- Department of Mental Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA. .,Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA. .,Departments of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA. .,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA. .,Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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11
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Chen Q, Cao T, Li N, Zeng C, Zhang S, Wu X, Zhang B, Cai H. Repurposing of Anti-Diabetic Agents as a New Opportunity to Alleviate Cognitive Impairment in Neurodegenerative and Neuropsychiatric Disorders. Front Pharmacol 2021; 12:667874. [PMID: 34108878 PMCID: PMC8182376 DOI: 10.3389/fphar.2021.667874] [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] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/07/2021] [Indexed: 12/16/2022] Open
Abstract
Cognitive impairment is a shared abnormality between type 2 diabetes mellitus (T2DM) and many neurodegenerative and neuropsychiatric disorders, such as Alzheimer’s disease (AD) and schizophrenia. Emerging evidence suggests that brain insulin resistance plays a significant role in cognitive deficits, which provides the possibility of anti-diabetic agents repositioning to alleviate cognitive deficits. Both preclinical and clinical studies have evaluated the potential cognitive enhancement effects of anti-diabetic agents targeting the insulin pathway. Repurposing of anti-diabetic agents is considered to be promising for cognitive deficits prevention or control in these neurodegenerative and neuropsychiatric disorders. This article reviewed the possible relationship between brain insulin resistance and cognitive deficits. In addition, promising therapeutic interventions, especially current advances in anti-diabetic agents targeting the insulin pathway to alleviate cognitive impairment in AD and schizophrenia were also summarized.
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Affiliation(s)
- Qian Chen
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacy, Central South University, Changsha, China
| | - Ting Cao
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacy, Central South University, Changsha, China
| | - NaNa Li
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacy, Central South University, Changsha, China
| | - Cuirong Zeng
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacy, Central South University, Changsha, China
| | - Shuangyang Zhang
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacy, Central South University, Changsha, China
| | - Xiangxin Wu
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacy, Central South University, Changsha, China
| | - Bikui Zhang
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacy, Central South University, Changsha, China
| | - Hualin Cai
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacy, Central South University, Changsha, China
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12
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Tanokashira D, Wang W, Maruyama M, Kuroiwa C, White MF, Taguchi A. Irs2 deficiency alters hippocampus-associated behaviors during young adulthood. Biochem Biophys Res Commun 2021; 559:148-154. [PMID: 33940386 DOI: 10.1016/j.bbrc.2021.04.101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 04/24/2021] [Indexed: 10/21/2022]
Abstract
Type 2 diabetes mellitus (T2DM), characterized by hyperglycemia and insulin resistance, has been recognized as a risk factor for cognitive impairment and dementia, including Alzheimer's disease (AD). Insulin receptor substrate2 (IRS2) is a major component of the insulin/insulin-like growth factor-1 signaling pathway. Irs2 deletion leads to life-threatening T2DM, promoting premature death in male mice regardless of their genetic background. Here, we showed for the first time that young adult male mice lacking Irs2 on a C57BL/6J genetic background (Irs2-/-/6J) survived in different experimental environments and displayed hippocampus-associated behavioral alterations. Young adult male Irs2-/-/6J mice also exhibit aberrant alterations in energy and nutrient sensors, such as AMP-activated protein kinase (AMPK) and glucose transporter3 (GLUT3), and reduced core body temperature accompanied by abnormal change in the temperature sensor in the brain. These results suggest that Irs2 deficiency-induced impairments of brain energy metabolism and thermoregulation contribute to hippocampus-associated behavioral changes in young adult male mice.
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Affiliation(s)
- Daisuke Tanokashira
- Department of Integrative Neuroscience, National Center for Geriatrics and Gerontology, Obu, Aichi, 474-8511, Japan
| | - Wei Wang
- Department of Integrative Neuroscience, National Center for Geriatrics and Gerontology, Obu, Aichi, 474-8511, Japan
| | - Megumi Maruyama
- Department of Integrative Neuroscience, National Center for Geriatrics and Gerontology, Obu, Aichi, 474-8511, Japan
| | - Chiemi Kuroiwa
- Department of Integrative Neuroscience, National Center for Geriatrics and Gerontology, Obu, Aichi, 474-8511, Japan
| | - Morris F White
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Akiko Taguchi
- Department of Integrative Neuroscience, National Center for Geriatrics and Gerontology, Obu, Aichi, 474-8511, Japan.
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13
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Iñiguez SD, Flores-Ramirez FJ, Themann A, Lira O. Adolescent Fluoxetine Exposure Induces Persistent Gene Expression Changes in the Hippocampus of Adult Male C57BL/6 Mice. Mol Neurobiol 2021; 58:1683-1694. [PMID: 33241493 PMCID: PMC7933079 DOI: 10.1007/s12035-020-02221-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 11/18/2020] [Indexed: 02/03/2023]
Abstract
Mood-related disorders have a high prevalence among children and adolescents, posing a public health challenge, given their adverse impact on these young populations. Treatment with the selective serotonin reuptake inhibitor fluoxetine (FLX) is the first line of pharmacological intervention in pediatric patients suffering from affect-related illnesses. Although the use of this antidepressant has been deemed efficacious in the juvenile population, the enduring neurobiological consequences of adolescent FLX exposure are not well understood. Therefore, we explored for persistent molecular adaptations, in the adult hippocampus, as a function of adolescent FLX pretreatment. To do this, we administered FLX (20 mg/kg/day) to male C57BL/6 mice during adolescence (postnatal day [PD] 35-49). After a 21-day washout period (PD70), whole hippocampal tissue was dissected. We then used qPCR analysis to assess changes in the expression of genes associated with major intracellular signal transduction pathways, including the extracellular signal-regulated kinase (ERK), the phosphatidylinositide-3-kinase (PI3K)/AKT pathway, and the wingless (Wnt)-dishevelled-GSK3β signaling cascade. Our results show that FLX treatment results in long-term dysregulation of mRNA levels across numerous genes from the ERK, PI3K/AKT, and Wnt intracellular signaling pathways, along with increases of the transcription factors CREB, ΔFosB, and Zif268. Lastly, FLX treatment resulted in persistent increases of transcripts associated with cytoskeletal integrity (β-actin) and caspase activation (DIABLO), while decreasing genes associated with metabolism (fucose kinase) and overall neuronal activation (c-Fos). Collectively, these data indicate that adolescent FLX exposure mediates persistent alterations in hippocampal gene expression in adulthood, thus questioning the safety of early-life exposure to this antidepressant medication.
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Affiliation(s)
- Sergio D Iñiguez
- Department of Psychology, The University of Texas at El Paso, 500 West University Avenue, El Paso, TX, 79968, USA.
| | - Francisco J Flores-Ramirez
- Department of Psychology, The University of Texas at El Paso, 500 West University Avenue, El Paso, TX, 79968, USA
| | - Anapaula Themann
- Department of Psychology, The University of Texas at El Paso, 500 West University Avenue, El Paso, TX, 79968, USA
| | - Omar Lira
- Department of Psychology, The University of Texas at El Paso, 500 West University Avenue, El Paso, TX, 79968, USA
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14
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Toyoshima Y, Nakamura K, Tokita R, Teramoto N, Sugihara H, Kato H, Yamanouchi K, Minami S. Disruption of insulin receptor substrate-2 impairs growth but not insulin function in rats. J Biol Chem 2020; 295:11914-11927. [PMID: 32631952 DOI: 10.1074/jbc.ra120.013095] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 07/01/2020] [Indexed: 11/06/2022] Open
Abstract
Insulin receptor substrate (IRS)-2, along with IRS-1, is a key signaling molecule that mediates the action of insulin and insulin-like growth factor (IGF)-I. The activated insulin and IGF-I receptors phosphorylate IRSs on tyrosine residues, leading to the activation of downstream signaling pathways and the induction of various physiological functions of insulin and IGF-I. Studies using IRS-2 knockout (KO) mice showed that the deletion of IRS-2 causes type 2 diabetes due to peripheral insulin resistance and impaired β-cell function. However, little is known about the roles of IRS-2 in other animal models. Here, we created IRS-2 KO rats to elucidate the physiological functions of IRS-2 in rats. The body weights of IRS-2 KO rats at birth were lower compared with those of their WT littermates. The postnatal growth of both male and female IRS-2 KO rats was also suppressed. Compared with male WT rats, the glucose and insulin tolerance of male IRS-2 KO rats were slightly enhanced, whereas a similar difference was not observed between female WT and IRS-2 KO rats. Besides the modestly increased insulin sensitivity, male IRS-2 KO rats displayed the enhanced insulin-induced activation of the mTOR complex 1 pathway in the liver compared with WT rats. Taken together, these results indicate that in rats, IRS-2 plays important roles in the regulation of growth but is not essential for the glucose-lowering effects of insulin.
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Affiliation(s)
- Yuka Toyoshima
- Department of Bioregulation, Institute for Advanced Medical Sciences, Nippon Medical School, Kosugi-machi, Nakahara-ku, Kawasaki, Japan
| | - Katsuyuki Nakamura
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Reiko Tokita
- Department of Bioregulation, Institute for Advanced Medical Sciences, Nippon Medical School, Kosugi-machi, Nakahara-ku, Kawasaki, Japan
| | - Naomi Teramoto
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Hidetoshi Sugihara
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Hisanori Kato
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Keitaro Yamanouchi
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Shiro Minami
- Department of Bioregulation, Institute for Advanced Medical Sciences, Nippon Medical School, Kosugi-machi, Nakahara-ku, Kawasaki, Japan
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15
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Spinelli M, Fusco S, Grassi C. Brain insulin resistance impairs hippocampal plasticity. VITAMINS AND HORMONES 2020; 114:281-306. [PMID: 32723548 DOI: 10.1016/bs.vh.2020.04.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Nutrient-related signals have been demonstrated to influence brain development and cognitive functions. In particular, insulin signaling has been shown to impact on molecular cascades underlying hippocampal plasticity, learning and memory. Alteration of brain insulin signaling interferes with the maintenance of neural stem cell niche and neuronal activity in the hippocampus. Brain insulin resistance is also emerging as key factor causing the cognitive impairment observed in metabolic and neurodegenerative diseases. Here, we review the molecular mechanisms involved in the insulin modulation of both adult neurogenesis and synaptic activity in the hippocampus. We also summarize the effects of altered insulin sensitivity on hippocampal plasticity. Finally, we reassume the experimental and epidemiological evidence highlighting the critical role of brain insulin resistance at the crossroad between type 2 diabetes and Alzheimer's disease.
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Affiliation(s)
- Matteo Spinelli
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Salvatore Fusco
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy; Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.
| | - Claudio Grassi
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy; Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.
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16
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Deme P, Rojas C, Slusher BS, Rais R, Afghah Z, Geiger JD, Haughey NJ. Bioenergetic adaptations to HIV infection. Could modulation of energy substrate utilization improve brain health in people living with HIV-1? Exp Neurol 2020; 327:113181. [PMID: 31930991 PMCID: PMC7233457 DOI: 10.1016/j.expneurol.2020.113181] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 12/10/2019] [Accepted: 01/10/2020] [Indexed: 12/18/2022]
Abstract
The human brain consumes more energy than any other organ in the body and it relies on an uninterrupted supply of energy in the form of adenosine triphosphate (ATP) to maintain normal cognitive function. This constant supply of energy is made available through an interdependent system of metabolic pathways in neurons, glia and endothelial cells that each have specialized roles in the delivery and metabolism of multiple energetic substrates. Perturbations in brain energy metabolism is associated with a number of different neurodegenerative conditions including impairments in cognition associated with infection by the Human Immunodeficiency Type 1 Virus (HIV-1). Adaptive changes in brain energy metabolism are apparent early following infection, do not fully normalize with the initiation of antiretroviral therapy (ART), and often worsen with length of infection and duration of anti-retroviral therapeutic use. There is now a considerable amount of cumulative evidence that suggests mild forms of cognitive impairments in people living with HIV-1 (PLWH) may be reversible and are associated with specific modifications in brain energy metabolism. In this review we discuss brain energy metabolism with an emphasis on adaptations that occur in response to HIV-1 infection. The potential for interventions that target brain energy metabolism to preserve or restore cognition in PLWH are also discussed.
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Affiliation(s)
- Pragney Deme
- The Johns Hopkins University School of Medicine, Department of Neurology, United States
| | - Camilo Rojas
- The Johns Hopkins University School of Medicine, Department of Comparative Medicine and Pathobiology, United States
| | - Barbara S Slusher
- The Johns Hopkins University School of Medicine, Department of Neurology, United States; The Johns Hopkins University School of Medicine, Department of The Solomon H. Snyder Department of Neuroscience, United States; The Johns Hopkins University School of Medicine, Department of Comparative Medicine and Pathobiology, United States; The Johns Hopkins University School of Medicine, Department of Psychiatry, United States
| | - Raina Rais
- The Johns Hopkins University School of Medicine, Department of Neurology, United States; The Johns Hopkins University School of Medicine, Department of The Solomon H. Snyder Department of Neuroscience, United States; The Johns Hopkins University School of Medicine, Department of Comparative Medicine and Pathobiology, United States; The Johns Hopkins University School of Medicine, Department of Psychiatry, United States
| | - Zahra Afghah
- The University of North Dakota School of Medicine and Health Sciences, Department of Biomedical Sciences, United States
| | - Jonathan D Geiger
- The University of North Dakota School of Medicine and Health Sciences, Department of Biomedical Sciences, United States
| | - Norman J Haughey
- The Johns Hopkins University School of Medicine, Department of Neurology, United States; The Johns Hopkins University School of Medicine, Department of Psychiatry, United States.
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17
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Dopamine regulates spine density in striatal projection neurons in a concentration-dependent manner. Neurobiol Dis 2020; 134:104666. [DOI: 10.1016/j.nbd.2019.104666] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 10/24/2019] [Accepted: 10/31/2019] [Indexed: 02/07/2023] Open
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18
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Wang Y, Wang P, Chen F, Lulu M, Huang S, Liu Z. Potential synaptic plasticity-based Shenzhiling oral liquid for a SAD Mouse Model. Brain Behav 2019; 9:e01385. [PMID: 31429527 PMCID: PMC6749598 DOI: 10.1002/brb3.1385] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 07/02/2019] [Accepted: 07/03/2019] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Synaptic plasticity is the basis of memory formation. The pathological manifestations of abnormal glucose metabolism in the nervous system of sporadic Alzheimer's disease (SAD) may affect synaptic plasticity, thus causing memory damage. As a traditional Chinese medicine compound preparation, the mechanism by which Shenzhiling (SZL) oral liquid can alleviate the cognitive impairment of SAD by improving synaptic plasticity remains unclear. OBJECTIVE This article mainly discusses whether SZL can exert a protective synaptic effect as mediated by glutamate receptors and glycogen synthesis kinase 3β (GSK3β); further, it discusses whether SZL can improve cognitive function in SAD. METHODS C57BL/6 mice were used as a SAD model after injection with streptozotocin (STZ) into the bilateral lateral ventricles; mice of the same background were injected with artificial cerebrospinal fluid into bilateral ventricles and were used as a control group. After 3 months of exposure to the intervention, the step-down test was carried out. Western blot was used to detect the levels of NMDAR2B, p-NMDAR2B, mGlu5, GSK3β, and p-GSK3β in the hippocampus of mice. Immunohistochemical analysis was used to observe the number of GSK3β-positive cells in the CA1 region of mouse hippocampus. RESULTS The memory retention ability of mice was significantly improved after 3 months of SZL treatment, and the expression levels of NMDAR2B, mGlu5, and GSK3β were significantly changed. CONCLUSION Shenzhiling provides a potential for the treatment for SAD with traditional Chinese medicine.
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Affiliation(s)
- Yahan Wang
- Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital, Beijing University of Chinese Medicine (BUCM), Beijing, China.,Key Laboratory of Pharmacology of Dongzhimen Hospital (BUCM), State Administration of Traditional Chinese Medicine, Beijing, China
| | - Pengwen Wang
- Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital, Beijing University of Chinese Medicine (BUCM), Beijing, China.,Key Laboratory of Pharmacology of Dongzhimen Hospital (BUCM), State Administration of Traditional Chinese Medicine, Beijing, China
| | - Fang Chen
- Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital, Beijing University of Chinese Medicine (BUCM), Beijing, China.,Key Laboratory of Pharmacology of Dongzhimen Hospital (BUCM), State Administration of Traditional Chinese Medicine, Beijing, China.,Rehabilitation centre, The Xinjiang Uygur Autonomous Region Traditional Chinese Medicine Hospital affiliated to Xinjiang Medical University, Urumqi, China
| | - Mana Lulu
- Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital, Beijing University of Chinese Medicine (BUCM), Beijing, China.,Key Laboratory of Pharmacology of Dongzhimen Hospital (BUCM), State Administration of Traditional Chinese Medicine, Beijing, China
| | - Shuaiyang Huang
- Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital, Beijing University of Chinese Medicine (BUCM), Beijing, China.,Key Laboratory of Pharmacology of Dongzhimen Hospital (BUCM), State Administration of Traditional Chinese Medicine, Beijing, China
| | - Zhenhong Liu
- Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing, Dongzhimen Hospital, Beijing University of Chinese Medicine (BUCM), Beijing, China.,Key Laboratory of Pharmacology of Dongzhimen Hospital (BUCM), State Administration of Traditional Chinese Medicine, Beijing, China
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19
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[The relations between neural insulin signaling and metabolic and neural dysfunctions]. Nihon Ronen Igakkai Zasshi 2019; 56:234-240. [PMID: 31366741 DOI: 10.3143/geriatrics.56.234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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20
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Mazucanti CH, Kawamoto EM, Mattson MP, Scavone C, Camandola S. Activity-dependent neuronal Klotho enhances astrocytic aerobic glycolysis. J Cereb Blood Flow Metab 2019; 39:1544-1556. [PMID: 29493420 PMCID: PMC6681535 DOI: 10.1177/0271678x18762700] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Mutations of the β-glucuronidase protein α-Klotho have been associated with premature aging, and altered cognitive function. Although highly expressed in specific areas of the brain, Klotho functions in the central nervous system remain unknown. Here, we show that cultured hippocampal neurons respond to insulin and glutamate stimulation by elevating Klotho protein levels. Conversely, AMPA and NMDA antagonism suppress neuronal Klotho expression. We also provide evidence that soluble Klotho enhances astrocytic aerobic glycolysis by hindering pyruvate metabolism through the mitochondria, and stimulating its processing by lactate dehydrogenase. Pharmacological inhibition of FGFR1, Erk phosphorylation, and monocarboxylic acid transporters prevents Klotho-induced lactate release from astrocytes. Taken together, these data suggest Klotho is a potential new player in the metabolic coupling between neurons and astrocytes. Neuronal glutamatergic activity and insulin modulation elicit Klotho release, which in turn stimulates astrocytic lactate formation and release. Lactate can then be used by neurons and other cells types as a metabolic substrate.
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Affiliation(s)
- Caio H Mazucanti
- 1 Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Elisa M Kawamoto
- 1 Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Mark P Mattson
- 2 Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, USA.,3 Department of Neurosciences, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Cristoforo Scavone
- 1 Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Simonetta Camandola
- 2 Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, USA
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21
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Spinelli M, Fusco S, Grassi C. Brain Insulin Resistance and Hippocampal Plasticity: Mechanisms and Biomarkers of Cognitive Decline. Front Neurosci 2019; 13:788. [PMID: 31417349 PMCID: PMC6685093 DOI: 10.3389/fnins.2019.00788] [Citation(s) in RCA: 134] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/15/2019] [Indexed: 12/27/2022] Open
Abstract
In the last decade, much attention has been devoted to the effects of nutrient-related signals on brain development and cognitive functions. A turning point was the discovery that brain areas other than the hypothalamus expressed receptors for hormones related to metabolism. In particular, insulin signaling has been demonstrated to impact on molecular cascades underlying hippocampal plasticity, learning and memory. Here, we summarize the molecular evidence linking alteration of hippocampal insulin sensitivity with changes of both adult neurogenesis and synaptic plasticity. We also review the epidemiological studies and experimental models emphasizing the critical role of brain insulin resistance at the crossroad between metabolic and neurodegenerative disease. Finally, we brief novel findings suggesting how biomarkers of brain insulin resistance, involving the study of brain-derived extracellular vesicles and brain glucose metabolism, may predict the onset and/or the progression of cognitive decline.
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Affiliation(s)
- Matteo Spinelli
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Salvatore Fusco
- Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
| | - Claudio Grassi
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
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22
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Martín‐Segura A, Ahmed T, Casadomé‐Perales Á, Palomares‐Perez I, Palomer E, Kerstens A, Munck S, Balschun D, Dotti CG. Age-associated cholesterol reduction triggers brain insulin resistance by facilitating ligand-independent receptor activation and pathway desensitization. Aging Cell 2019; 18:e12932. [PMID: 30884121 PMCID: PMC6516156 DOI: 10.1111/acel.12932] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 01/30/2019] [Accepted: 02/01/2019] [Indexed: 01/08/2023] Open
Abstract
In the brain, insulin plays an important role in cognitive processes. During aging, these faculties decline, as does insulin signaling. The mechanism behind this last phenomenon is unclear. In recent studies, we reported that the mild and gradual loss of cholesterol in the synaptic fraction of hippocampal neurons during aging leads to a decrease in synaptic plasticity evoked by glutamate receptor activation and also by receptor tyrosine kinase (RTK) signaling. As insulin and insulin growth factor activity are dependent on tyrosine kinase receptors, we investigated whether the constitutive loss of brain cholesterol is also involved in the decay of insulin function with age. Using long‐term depression (LTD) induced by application of insulin to hippocampal slices as a read‐out, we found that the decline in insulin function during aging could be monitored as a progressive impairment of insulin‐LTD. The application of a cholesterol inclusion complex, which donates cholesterol to the membrane and increases membrane cholesterol levels, rescued the insulin signaling deficit and insulin‐LTD. In contrast, extraction of cholesterol from hippocampal neurons of adult mice produced the opposite effect. Furthermore, in vivo inhibition of Cyp46A1, an enzyme involved in brain cholesterol loss with age, improved insulin signaling. Fluorescence resonance energy transfer (FRET) experiments pointed to a change in receptor conformation by reduced membrane cholesterol, favoring ligand‐independent autophosphorylation. Together, these results indicate that changes in membrane fluidity of brain cells during aging play a key role in the decay of synaptic plasticity and cognition that occurs at this late stage of life.
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Affiliation(s)
- Adrián Martín‐Segura
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa CSIC/UAM Madrid Spain
- Department of Developmental and Molecular Biology Albert Einstein College of Medicine Bronx New York
| | - Tariq Ahmed
- Faculty of Psychology & Educational Sciences University of Leuven Leuven Belgium
- Neurological Disorders Research Center QBRI‐HBKU Doha Qatar
| | - Álvaro Casadomé‐Perales
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa CSIC/UAM Madrid Spain
| | - Irene Palomares‐Perez
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa CSIC/UAM Madrid Spain
| | - Ernest Palomer
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa CSIC/UAM Madrid Spain
- Cell & Developmental Biology Department University College London London UK
| | - Axelle Kerstens
- Department of Neuroscience, VIB Center for Brain and Disease Research University of Leuven Leuven Belgium
| | - Sebastian Munck
- Department of Neuroscience, VIB Center for Brain and Disease Research University of Leuven Leuven Belgium
| | - Detlef Balschun
- Faculty of Psychology & Educational Sciences University of Leuven Leuven Belgium
| | - Carlos G. Dotti
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa CSIC/UAM Madrid Spain
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23
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Matos TM, Souza-Talarico JND. How stress mediators can cumulatively contribute to Alzheimer's disease An allostatic load approach. Dement Neuropsychol 2019; 13:11-21. [PMID: 31073376 PMCID: PMC6497016 DOI: 10.1590/1980-57642018dn13-010002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 12/17/2018] [Indexed: 11/22/2022] Open
Abstract
Allostatic load is defined as the frequent activation of the neuroendocrine, immunological, metabolic and cardiovascular systems, which makes individuals more susceptible to stress-related health problems. According to this model, physiological dysregulations start to emerge decades before diseases manifest. Consequently, stress research has shifted its attention to anticipating the degree of this dysregulation to better understand the impact of stress hormones and other biomarkers on disease progression. In view of the growing number of studies that demonstrate the influence of modifiable risk factors on cognitive decline, in addition to the effects of chronic stress mediators, the objective of the present review was to present an overview of the development of cognitive changes based on studies on stress and its mediators.
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Affiliation(s)
- Tatiane Martins Matos
- Nurse, Master of Science from the School of Nursing, University of
São Paulo (EE-USP), SP, Brazil
| | - Juliana Nery De Souza-Talarico
- Professor at the Department of Medical-Surgical Nursing, School of
Nursing, University of São Paulo (EE-USP), SP, Brazil. PhD In the Area of
Neurobiology of Stress and Cognition
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24
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胡 冬, 李 雅, 梁 赵, 钟 瞾, 唐 杰, 廖 婧, 田 和, 佘 高, 刘 誉, 邢 会. [Long-term high-fat diet inhibits hippocampal expression of insulin receptor substrates and accelerates cognitive deterioration in obese rats]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2018; 38:460-465. [PMID: 29735448 PMCID: PMC6765670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Indexed: 10/15/2023]
Abstract
OBJECTIVE To assess the effect of long-term high-fat diet on the expressions of insulin receptor substrates in the hippocampus and spatial learning and memory ability of obese rats. METHODS A total of 100 4-week-old male SD rats were randomly divided into two groups and fed with common diet (CD group, n=40) or high-fat diet (HFD group, n=60) for 16 weeks. At 4, 8, 12, 16 and 20 weeks, 8 rats were randomly selected from each group for testing their spatial learning and memory function using Morris water maze. After the tests, the rats were sacrificed for measurement of the metabolic parameters and detection of the expressions of insulin receptor substrate-1 (IRS-1) and IRS-2 mRNAs in the CA1 region of the hippocampus. RESULTS Compared with those in CD group, the rats in HFD group showed a prolonged escape latency, longer swimming distance, faster average swimming speed, and shorter stay in the platformat 12 weeks. In HFD group, the serum levels of total cholesterol, triglyceride, low-density lipoprotein cholesterol, and fasting insulin were all significantly increased (P<0.05) and the level of high-density lipoprotein cholesterol decreased (P<0.01) in comparison with those in CD group at each of the time points. No significant difference was found in fast glucose levels between the two groups (P>0.05), but the expressions of IRS-1 and IRS-2 mRNAs were significantly decreased in HFD group at 12 weeks (P<0.05). CONCLUSION In obese rats, long-term feeding with high-fat diet leads to insulin resistance, which interferes with hippocampal expression of insulin receptor substrates and insulin metabolism to cause impairment of the cognitive function and accelerate cognitive deterioration.
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Affiliation(s)
- 冬华 胡
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 雅兰 李
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 赵佳 梁
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 瞾 钟
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 杰柯 唐
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 婧 廖
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 和 田
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 高明 佘
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 誉 刘
- 暨南大学 医学院生化教研室,广东 广州 510630Departmen of Biochemistry, Jinan University, Guangzhou 510630, China
| | - 会杰 邢
- 暨南大学 实验动物中心,广东 广州 510630Institute of Laboratory Animal Science, Jinan University, Guangzhou 510630, China
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胡 冬, 李 雅, 梁 赵, 钟 瞾, 唐 杰, 廖 婧, 田 和, 佘 高, 刘 誉, 邢 会. [Long-term high-fat diet inhibits hippocampal expression of insulin receptor substrates and accelerates cognitive deterioration in obese rats]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2018; 38:460-465. [PMID: 29735448 PMCID: PMC6765670 DOI: 10.3969/j.issn.1673-4254.2018.04.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Indexed: 06/08/2023]
Abstract
OBJECTIVE To assess the effect of long-term high-fat diet on the expressions of insulin receptor substrates in the hippocampus and spatial learning and memory ability of obese rats. METHODS A total of 100 4-week-old male SD rats were randomly divided into two groups and fed with common diet (CD group, n=40) or high-fat diet (HFD group, n=60) for 16 weeks. At 4, 8, 12, 16 and 20 weeks, 8 rats were randomly selected from each group for testing their spatial learning and memory function using Morris water maze. After the tests, the rats were sacrificed for measurement of the metabolic parameters and detection of the expressions of insulin receptor substrate-1 (IRS-1) and IRS-2 mRNAs in the CA1 region of the hippocampus. RESULTS Compared with those in CD group, the rats in HFD group showed a prolonged escape latency, longer swimming distance, faster average swimming speed, and shorter stay in the platformat 12 weeks. In HFD group, the serum levels of total cholesterol, triglyceride, low-density lipoprotein cholesterol, and fasting insulin were all significantly increased (P<0.05) and the level of high-density lipoprotein cholesterol decreased (P<0.01) in comparison with those in CD group at each of the time points. No significant difference was found in fast glucose levels between the two groups (P>0.05), but the expressions of IRS-1 and IRS-2 mRNAs were significantly decreased in HFD group at 12 weeks (P<0.05). CONCLUSION In obese rats, long-term feeding with high-fat diet leads to insulin resistance, which interferes with hippocampal expression of insulin receptor substrates and insulin metabolism to cause impairment of the cognitive function and accelerate cognitive deterioration.
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Affiliation(s)
- 冬华 胡
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 雅兰 李
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 赵佳 梁
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 瞾 钟
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 杰柯 唐
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 婧 廖
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 和 田
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 高明 佘
- 暨南大学 附属第一院麻醉科,广东 广州 510630Department of Anesthesia of First Affiliated Hospital, Jinan University, Guangzhou 510630, China
| | - 誉 刘
- 暨南大学 医学院生化教研室,广东 广州 510630Departmen of Biochemistry, Jinan University, Guangzhou 510630, China
| | - 会杰 邢
- 暨南大学 实验动物中心,广东 广州 510630Institute of Laboratory Animal Science, Jinan University, Guangzhou 510630, China
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Insulin-mediated synaptic plasticity in the CNS: Anatomical, functional and temporal contexts. Neuropharmacology 2017; 136:182-191. [PMID: 29217283 PMCID: PMC5988909 DOI: 10.1016/j.neuropharm.2017.12.001] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 12/01/2017] [Accepted: 12/03/2017] [Indexed: 12/17/2022]
Abstract
For decades the brain was erroneously considered an insulin insensitive organ. Although gaps in our knowledge base remain, conceptual frameworks are starting to emerge to provide insight into the mechanisms through which insulin facilitates critical brain functions like metabolism, cognition, and motivated behaviors. These diverse physiological and behavioral activities highlight the region-specific activities of insulin in the CNS; that is, there is an anatomical context to the activities of insulin in the CNS. Similarly, there is also a temporal context to the activities of insulin in the CNS. Indeed, brain insulin receptor activity can be conceptualized as a continuum in which insulin promotes neuroplasticity from development into adulthood where it is an integral part of healthy brain function. Unfortunately, brain insulin resistance likely contributes to neuroplasticity deficits in obesity and type 2 diabetes mellitus (T2DM). This neuroplasticity continuum can be conceptualized by the mechanisms through which insulin promotes cognitive function through its actions in brain regions like the hippocampus, as well as the ability of insulin to modulate motivated behaviors through actions in brain regions like the nucleus accumbens and the ventral tegmental area. Thus, the goals of this review are to highlight these anatomical, temporal, and functional contexts of insulin activity in these brain regions, and to identify potentially critical time points along this continuum where the transition from enhancement of neuroplasticity to impairment may take place.
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Lao-Peregrín C, Ballesteros JJ, Fernández M, Zamora-Moratalla A, Saavedra A, Gómez Lázaro M, Pérez-Navarro E, Burks D, Martín ED. Caffeine-mediated BDNF release regulates long-term synaptic plasticity through activation of IRS2 signaling. Addict Biol 2017; 22:1706-1718. [PMID: 27457910 PMCID: PMC5697621 DOI: 10.1111/adb.12433] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 06/23/2016] [Accepted: 06/27/2016] [Indexed: 11/27/2022]
Abstract
Caffeine has cognitive‐enhancing properties with effects on learning and memory, concentration, arousal and mood. These effects imply changes at circuital and synaptic level, but the mechanism by which caffeine modifies synaptic plasticity remains elusive. Here we report that caffeine, at concentrations representing moderate to high levels of consumption in humans, induces an NMDA receptor‐independent form of LTP (CAFLTP) in the CA1 region of the hippocampus by promoting calcium‐dependent secretion of BDNF, which subsequently activates TrkB‐mediated signaling required for the expression of CAFLTP. Our data include the novel observation that insulin receptor substrate 2 (IRS2) is phosphorylated during induction of CAFLTP, a process that requires cytosolic free Ca2+. Consistent with the involvement of IRS2 signals in caffeine‐mediated synaptic plasticity, phosphorylation of Akt (Ser473) in response to LTP induction is defective in Irs2−/− mice, demonstrating that these plasticity changes are associated with downstream targets of the phosphoinositide 3‐kinase (PI3K) pathway. These findings indicate that TrkB‐IRS2 signals are essential for activation of PI3K during the induction of LTP by caffeine.
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Affiliation(s)
- Cristina Lao-Peregrín
- Laboratory of Neurophysiology and Synaptic Plasticity, Castilla-La Mancha Science and Technology Park (PCYTCLM), Institute for Research in Neurological Disabilities (IDINE); University of Castilla-La Mancha; Spain
| | - Jesús Javier Ballesteros
- Laboratory of Neurophysiology and Synaptic Plasticity, Castilla-La Mancha Science and Technology Park (PCYTCLM), Institute for Research in Neurological Disabilities (IDINE); University of Castilla-La Mancha; Spain
| | - Miriam Fernández
- Laboratory of Neurophysiology and Synaptic Plasticity, Castilla-La Mancha Science and Technology Park (PCYTCLM), Institute for Research in Neurological Disabilities (IDINE); University of Castilla-La Mancha; Spain
| | - Alfonsa Zamora-Moratalla
- Laboratory of Neurophysiology and Synaptic Plasticity, Castilla-La Mancha Science and Technology Park (PCYTCLM), Institute for Research in Neurological Disabilities (IDINE); University of Castilla-La Mancha; Spain
| | - Ana Saavedra
- Departament de Biomedicina, Facultat de Medicina; Universitat de Barcelona; Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS); Spain
- Centro de Investigación Biomédica en Red (CIBER) sobre Enfermedades Neurodegenerativas (CIBERNED); Spain
- Institut de Neurociències; Universitat de Barcelona; Spain
| | - María Gómez Lázaro
- Laboratory of Neurophysiology and Synaptic Plasticity, Castilla-La Mancha Science and Technology Park (PCYTCLM), Institute for Research in Neurological Disabilities (IDINE); University of Castilla-La Mancha; Spain
| | - Esther Pérez-Navarro
- Departament de Biomedicina, Facultat de Medicina; Universitat de Barcelona; Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS); Spain
- Centro de Investigación Biomédica en Red (CIBER) sobre Enfermedades Neurodegenerativas (CIBERNED); Spain
- Institut de Neurociències; Universitat de Barcelona; Spain
| | - Deborah Burks
- Centro de Investigación Príncipe Felipe, CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM); Spain
| | - Eduardo D. Martín
- Laboratory of Neurophysiology and Synaptic Plasticity, Castilla-La Mancha Science and Technology Park (PCYTCLM), Institute for Research in Neurological Disabilities (IDINE); University of Castilla-La Mancha; Spain
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Hypertension-induced synapse loss and impairment in synaptic plasticity in the mouse hippocampus mimics the aging phenotype: implications for the pathogenesis of vascular cognitive impairment. GeroScience 2017; 39:385-406. [PMID: 28664509 DOI: 10.1007/s11357-017-9981-y] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 05/30/2017] [Indexed: 12/22/2022] Open
Abstract
Strong epidemiological and experimental evidence indicates that hypertension has detrimental effects on the cerebral microcirculation and thereby promotes accelerated brain aging. Hypertension is an independent risk factor for both vascular cognitive impairment (VCI) and Alzheimer's disease (AD). However, the pathophysiological link between hypertension-induced cerebromicrovascular injury (e.g., blood-brain barrier disruption, increased microvascular oxidative stress, and inflammation) and cognitive decline remains elusive. The present study was designed to characterize neuronal functional and morphological alterations induced by chronic hypertension and compare them to those induced by aging. To achieve that goal, we induced hypertension in young C57BL/6 mice by chronic (4 weeks) infusion of angiotensin II. We found that long-term potentiation (LTP) of performant path synapses following high-frequency stimulation of afferent fibers was decreased in hippocampal slices obtained from hypertensive mice, mimicking the aging phenotype. Hypertension and advanced age were associated with comparable decline in synaptic density in the stratum radiatum of the mouse hippocampus. Hypertension, similar to aging, was associated with changes in mRNA expression of several genes involved in regulation of neuronal function, including down-regulation of Bdnf, Homer1, and Dlg4, which may have a role in impaired synaptic plasticity. Collectively, hypertension impairs synaptic plasticity, reduces synaptic density, and promotes dysregulation of genes involved in synaptic function in the mouse hippocampus mimicking the aging phenotype. These hypertension-induced neuronal alterations may impair establishment of memories in the hippocampus and contribute to the pathogenesis and clinical manifestation of both vascular cognitive impairment (VCI) and Alzheimer's disease (AD).
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Abstract
Both Alzheimer's disease (AD) and type 2 diabetes mellitus (DM) are two common
forms of disease worldwide and many studies indicate that people with diabetes,
especially DM, are at higher risk of developing AD. AD is characterized by
progressive cognitive decline and accumulation of β-amyloid (Aβ)
forming senile plaques. DM is a metabolic disorder characterized by
hyperglycemia in the context of insulin resistance and relative lack of insulin.
Both diseases also share common characteristics such as loss of cognitive
function and inflammation. Inflammation resulting from Aβ further induces
production of Aβ1-42 peptides. Inflammation due to
overnutrition induces insulin resistance and consequently DM. Memory deficit and
a decrease in GLUT4 and hippocampal insulin signaling have been observed in
animal models of insulin resistance. The objective of this review was to show
the shared characteristics of AD and DM.
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Affiliation(s)
- Aparecida Marcelino de Nazareth
- Physiotherapist, Specialist in Neurofunctional Physical Therapy, Master of Neurosciences from the (UFSC), SC, Brazil, and PhD in Sciences (Pharmacology and Medicinal Chemistry) from the Federal University of Rio de Janeiro (UFRJ), RJ, Brazil
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Regulation of insulin receptor phosphorylation in the brains of prenatally stressed rats: New insight into the benefits of antidepressant drug treatment. Eur Neuropsychopharmacol 2017; 27:120-131. [PMID: 28063625 DOI: 10.1016/j.euroneuro.2016.12.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 12/20/2016] [Accepted: 12/22/2016] [Indexed: 01/03/2023]
Abstract
A growing body of evidence supports the involvement of disturbances in the brain insulin pathway in the pathogenesis of depression. On the other hand, data concerning the impact of antidepressant drug therapy on brain insulin signaling remain scare and insufficient. We determinated the influence of chronic treatment with antidepressant drugs (imipramine, fluoxetine and tianeptine) on the insulin signaling pathway of the brain of adult prenatally stressed rats. 3-month-old prenatally stressed and control rats were treated for 21 days with imipramine, fluoxetine or tianeptine (10mg/kg/day i.p.).The impact of chronic antidepressant administration was examined in forced swim test. In the frontal cortex and hippocampus, the mRNA and protein expression of insulin, insulin receptor, insulin receptor substrates (IRS-1,IRS-2) and adaptor proteins (Shc1, Grb2) before and after drugs administration were measured.Rats exposed prenatally to stressful stimuli displayed depressive-like disturbances, which were attenuated by antidepressant drug administration. We did not reveal the impact of prenatal stress or antidepressant treatment on insulin and the insulin receptor expression in the examined structures. We revealed that diminished insulin receptor phosphorylation evoked by the prenatal stress procedure was attenuated by drugs treatment. We demonstrated that the favorable effect of antidepressans on insulin receptor phosphorylation in the frontal cortex was mainly related with the normalization of serine312 and tyrosine IRS-1 phosphorylation, while in the hippocampus, it was related with the adaptor proteins Shc1/Grb2. It can be suggested that the behavioral effectiveness of antidepressant drug therapy may be related with the beneficial impact of antidepressant on insulin receptor phosphorylation pathways.
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Tang N, Jiang R, Wang X, Wen J, Liu L, Wu J, Zhang C. Insulin resistance plays a potential role in postoperative cognitive dysfunction in patients following cardiac valve surgery. Brain Res 2016; 1657:377-382. [PMID: 28048971 DOI: 10.1016/j.brainres.2016.12.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 12/25/2016] [Accepted: 12/28/2016] [Indexed: 11/28/2022]
Abstract
Severe insulin resistance (IR) promotes the development of Alzheimer disease. IR and postoperative cognitive dysfunction (POCD) are a common complication during the cardiac perioperative period. The authors hypothesized that IR of individuals with cardiac valve surgery would have increased the risk of POCD. The purpose of the study was to analyze the association of IR and POCD after cardiac valve surgery. Total 131 patients who underwent valve replacement via cardiopulmonary bypass (CPB) were included. Cognitive function was assessed by a series of neuropsychological measurements at 1day before and 7days after the surgery. 40 healthy volunteers as the control group also completed the neuropsychological assessment at the same time point. POCD was identified using the "Z score" method. Fasting blood glucose and insulin levels were detected before anesthesia and at 6h and 7days post-operation. Additionally serum levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) were measured at 6h post-operation. The insulin resistance index was calculated by "homeostasis model assessment 2" (HOMA2) software. The relationship between IR and POCD or TNF-α, IL-6 was then analyzed. At 7days after surgery, the incidence of POCD was 43.8%. The levels of HOMA2-IR in patients with POCD were significantly higher than those of patients without POCD at 6h and 7days after operation (P<0.05).The levels of serum IL-6 and TNF- α were positively correlated with HOMA2-IR value at 6h after operation (RIL-6=0.426, P<0.01; RTNF-a=0.381, P<0.01). POCD was correlated with the patients' education age (OR=1.062), CPB time (OR=1.018), self-rating depression scale (SDS) score after operation (OR=1.082), HOMA2-IR at 6h (OR=1.110) and 7days (OR=13.762) after operation, IL-6 (OR=1.036) and TNF-α (OR=1.039) at 6h after operation. Our study suggests that IR is correlated with the incidence of POCD and the increase of inflammatory factors.
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Affiliation(s)
- Ni Tang
- Department of Anesthesiology, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province 646000, China
| | - Rongrong Jiang
- Department of Anesthesiology, Pi County People's Hospital, Chengdu, Sichuan Province 646000, China
| | - Xiaobin Wang
- Department of Anesthesiology, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province 646000, China.
| | - Jian Wen
- Department of Anesthesiology, Xuyong County People's Hospital, Luzhou, Sichuan Province 646000, China
| | - Li Liu
- Department of Anesthesiology, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province 646000, China
| | - Jiali Wu
- Department of Anesthesiology, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province 646000, China
| | - Chunxiang Zhang
- Department of Pharmacology, Rush Medical College, Rush University, Chicago, IL 60612, USA
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Abstract
IRS proteins are cellular adaptor molecules that mediate many of the key metabolic actions of insulin. When tyrosine is phosphorylated by the activated insulin receptor, IRS proteins recruit downstream effectors, such as phosphoinositide 3-kinase and mitogen-activated protein kinase, in order to elicit cellular responses such as glucose uptake, lipid metabolism and cell proliferation. There are two main IRS proteins in humans (IRS1 and IRS2), both of which are widely expressed. Given their central role in the insulin signalling pathway, it is not surprising that male mice lacking Irs1 or Irs2 present with elevated blood glucose or type 2 diabetes, respectively. For reasons yet to be identified, female Irs2 (-/-) mice do not develop type 2 diabetes. A number of organs are affected by complications of diabetes; macrovascular complications include stroke and coronary artery disease, while nephropathy, neuropathy and retinopathy fall into the category of microvascular complications. Given the serious consequences of these complications on patient morbidity and mortality, it is essential to identify the molecular pathogenesis underlying diabetic complications, with a view to improving therapeutic intervention and patient outcomes. A number of recently published papers have converged on the hypothesis that the loss of insulin signalling and IRS proteins is instrumental to the development and/or progression of diabetic complications. This review will summarise some highlights from the published work in which this hypothesis is discussed.
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Affiliation(s)
- Deborah P Lavin
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, Northern Ireland, UK
| | - Morris F White
- Division of Endocrinology, Children's Hospital Boston, Harvard Medical School, Boston, MA, USA
| | - Derek P Brazil
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, Northern Ireland, UK.
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Bertram S, Brixius K, Brinkmann C. Exercise for the diabetic brain: how physical training may help prevent dementia and Alzheimer's disease in T2DM patients. Endocrine 2016; 53:350-63. [PMID: 27160819 DOI: 10.1007/s12020-016-0976-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 04/27/2016] [Indexed: 12/21/2022]
Abstract
Epidemiological studies indicate that patients with type 2 diabetes mellitus (T2DM) are at increased risk of developing dementia/Alzheimer's disease (AD). This review, which is based on recent studies, presents a molecular framework that links the two diseases and explains how physical training could help counteract neurodegeneration in T2DM patients. Inflammatory, oxidative, and metabolic changes in T2DM patients cause cerebrovascular complications and can lead to blood-brain-barrier (BBB) breakdown. Peripherally increased pro-inflammatory molecules can then pass the BBB more easily and activate stress-activated pathways, thereby promoting key pathological features of dementia/AD such as brain insulin resistance, mitochondrial dysfunction, and accumulation of neurotoxic beta-amyloid (Aβ) oligomers, leading to synaptic loss, neuronal dysfunction, and cell death. Ceramides can also pass the BBB, induce pro-inflammatory reactions, and disturb brain insulin signaling. In a vicious circle, oxidative stress and the pro-inflammatory environment intensify, leading to further cognitive decline. Low testosterone levels might be a common risk factor in T2DM and AD. Regular physical exercise reinforces antioxidative capacity, reduces oxidative stress, and has anti-inflammatory effects. It improves endothelial function and might increase brain capillarization. Physical training can further counteract dyslipidemia and reduce increased ceramide levels. It might also improve Aβ clearance by up-regulating Aβ transporters and, in some cases, increase basal testosterone levels. In addition, regular physical activity can induce neurogenesis. Physical training should therefore be emphasized as a part of prevention programs developed for diabetic patients to minimize the risk of the onset of neurodegenerative diseases among this specific patient group.
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Affiliation(s)
- Sebastian Bertram
- Institute of Cardiovascular Research and Sport Medicine, Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933, Cologne, Germany
| | - Klara Brixius
- Institute of Cardiovascular Research and Sport Medicine, Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933, Cologne, Germany
| | - Christian Brinkmann
- Institute of Cardiovascular Research and Sport Medicine, Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933, Cologne, Germany.
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Palleria C, Leporini C, Maida F, Succurro E, De Sarro G, Arturi F, Russo E. Potential effects of current drug therapies on cognitive impairment in patients with type 2 diabetes. Front Neuroendocrinol 2016; 42:76-92. [PMID: 27521218 DOI: 10.1016/j.yfrne.2016.07.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 07/13/2016] [Accepted: 07/22/2016] [Indexed: 02/07/2023]
Abstract
Type 2 diabetes mellitus is a complex metabolic disease that can cause serious damage to various organs. Among the best-known complications, an important role is played by cognitive impairment. Impairment of cognitive functioning has been reported both in type 1 and 2 diabetes mellitus. While this comorbidity has long been known, no major advances have been achieved in clinical research; it is clear that appropriate control of blood glucose levels represents the best current (although unsatisfactory) approach in the prevention of cognitive impairment. We have focused our attention on the possible effect on the brain of antidiabetic drugs, despite their effects on blood glucose levels, giving a brief rationale on the mechanisms (e.g. GLP-1, BDNF, ghrelin) that might be involved. Indeed, GLP-1 agonists are currently clinically studied in other neurodegenerative diseases (i.e. Parkinson's and Alzheimer's disease); furthermore, also other antidiabetic drugs have proven efficacy in preclinical studies. Overall, promising results are already available and finding new intervention strategies represents a current need in this field of research.
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Affiliation(s)
- Caterina Palleria
- Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, Italy
| | - Christian Leporini
- Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, Italy
| | - Francesca Maida
- Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, Italy
| | - Elena Succurro
- Department of Medical and Surgical Sciences, Internal Medicine Unit of "Mater Domini", University Hospital, University "Magna Graecia" of Catanzaro, Policlinico "Mater Domini", Campus Universitario, Viale Europa, 88100 Catanzaro, Italy
| | - Giovambattista De Sarro
- Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, Italy
| | - Franco Arturi
- Department of Medical and Surgical Sciences, Internal Medicine Unit of "Mater Domini", University Hospital, University "Magna Graecia" of Catanzaro, Policlinico "Mater Domini", Campus Universitario, Viale Europa, 88100 Catanzaro, Italy
| | - Emilio Russo
- Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, Italy.
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Dyer AH, Vahdatpour C, Sanfeliu A, Tropea D. The role of Insulin-Like Growth Factor 1 (IGF-1) in brain development, maturation and neuroplasticity. Neuroscience 2016; 325:89-99. [DOI: 10.1016/j.neuroscience.2016.03.056] [Citation(s) in RCA: 192] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 02/29/2016] [Accepted: 03/24/2016] [Indexed: 02/07/2023]
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Trueba-Saiz A, Torres Aleman I. Insulin-like peptides signaling in Alzheimer's disease: on the road to alternative therapeutics. Curr Opin Behav Sci 2016. [DOI: 10.1016/j.cobeha.2015.11.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Chami B, Steel AJ, De La Monte SM, Sutherland GT. The rise and fall of insulin signaling in Alzheimer's disease. Metab Brain Dis 2016; 31:497-515. [PMID: 26883429 DOI: 10.1007/s11011-016-9806-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/03/2016] [Indexed: 02/06/2023]
Abstract
The prevalence of both diabetes and Alzheimer's disease (AD) are reaching epidemic proportions worldwide. Alarmingly, diabetes is also a risk factor for Alzheimer's disease. The AD brain is characterised by the accumulation of peptides called Aβ as plaques in the neuropil and hyperphosphorylated tau protein in the form of neurofibrillary tangles within neurons. How diabetes confers risk is unknown but a simple linear relationship has been proposed whereby the hyperinsulinemia associated with type 2 diabetes leads to decreased insulin signaling in the brain, with downregulation of the PI3K/AKT signalling pathway and its inhibition of the major tau kinase, glycogen synthase kinase 3β. The earliest studies of post mortem AD brain tissue largely confirmed this cascade of events but subsequent studies have generally found either an upregulation of AKT activity, or that the relationship between insulin signaling and AD is independent of glycogen synthase kinase 3β altogether. Given the lack of success of beta-amyloid-reducing therapies in clinical trials, there is intense interest in finding alternative or adjunctive therapeutic targets for AD. Insulin signaling is a neuroprotective pathway and represents an attractive therapeutic option. However, this incredibly complex signaling pathway is not fully understood in the human brain and particularly in the context of AD. Here, we review the ups and downs of the research efforts aimed at understanding how diabetes modifies AD risk.
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Affiliation(s)
- B Chami
- Redox Biology, The University of Sydney, Sydney, NSW,, 2006, Australia
| | - A J Steel
- Neuropathology Group, Discipline of Pathology, Sydney Medical School, The University of Sydney, Sydney, NSW, 2006, Australia
| | - S M De La Monte
- Department of Neurology, Rhode Island Hospital and the Alpert Medical School of Brown University, Providence, RI, USA
- Department of Neurosurgery, Rhode Island Hospital and the Alpert Medical School of Brown University, Providence, RI, USA
- Department of Pathology, Rhode Island Hospital and the Alpert Medical School of Brown University, Providence, RI, USA
| | - Greg T Sutherland
- Neuropathology Group, Discipline of Pathology, Sydney Medical School, The University of Sydney, Sydney, NSW, 2006, Australia.
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Li Y, Sun W, Han S, Li J, Ding S, Wang W, Yin Y. IGF-1-Involved Negative Feedback of NR2B NMDA Subunits Protects Cultured Hippocampal Neurons Against NMDA-Induced Excitotoxicity. Mol Neurobiol 2016; 54:684-696. [DOI: 10.1007/s12035-015-9647-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Accepted: 12/16/2015] [Indexed: 11/28/2022]
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Grillo CA, Piroli GG, Lawrence RC, Wrighten SA, Green AJ, Wilson SP, Sakai RR, Kelly SJ, Wilson MA, Mott DD, Reagan LP. Hippocampal Insulin Resistance Impairs Spatial Learning and Synaptic Plasticity. Diabetes 2015; 64. [PMID: 26216852 PMCID: PMC4613975 DOI: 10.2337/db15-0596] [Citation(s) in RCA: 198] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Insulin receptors (IRs) are expressed in discrete neuronal populations in the central nervous system, including the hippocampus. To elucidate the functional role of hippocampal IRs independent of metabolic function, we generated a model of hippocampal-specific insulin resistance using a lentiviral vector expressing an IR antisense sequence (LV-IRAS). LV-IRAS effectively downregulates IR expression in the rat hippocampus without affecting body weight, adiposity, or peripheral glucose homeostasis. Nevertheless, hippocampal neuroplasticity was impaired in LV-IRAS-treated rats. High-frequency stimulation, which evoked robust long-term potentiation (LTP) in brain slices from LV control rats, failed to evoke LTP in LV-IRAS-treated rats. GluN2B subunit levels, as well as the basal level of phosphorylation of GluA1, were reduced in the hippocampus of LV-IRAS rats. Moreover, these deficits in synaptic transmission were associated with impairments in spatial learning. We suggest that alterations in the expression and phosphorylation of glutamate receptor subunits underlie the alterations in LTP and that these changes are responsible for the impairment in hippocampal-dependent learning. Importantly, these learning deficits are strikingly similar to the impairments in complex task performance observed in patients with diabetes, which strengthens the hypothesis that hippocampal insulin resistance is a key mediator of cognitive deficits independent of glycemic control.
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Affiliation(s)
- Claudia A Grillo
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC
| | - Gerardo G Piroli
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC
| | - Robert C Lawrence
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC Department of Psychology, University of South Carolina, Columbia, SC
| | - Shayna A Wrighten
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC
| | - Adrienne J Green
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC
| | - Steven P Wilson
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC
| | - Randall R Sakai
- Department of Psychiatry, University of Cincinnati Medical Center, Cincinnati, OH
| | - Sandra J Kelly
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC Department of Psychology, University of South Carolina, Columbia, SC
| | - Marlene A Wilson
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC William Jennings Bryan Dorn Veterans Affairs Medical Center, Columbia, SC
| | - David D Mott
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC
| | - Lawrence P Reagan
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC William Jennings Bryan Dorn Veterans Affairs Medical Center, Columbia, SC
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Walker JM, Harrison FE. Shared Neuropathological Characteristics of Obesity, Type 2 Diabetes and Alzheimer's Disease: Impacts on Cognitive Decline. Nutrients 2015; 7:7332-57. [PMID: 26340637 PMCID: PMC4586536 DOI: 10.3390/nu7095341] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Revised: 07/09/2015] [Accepted: 08/21/2015] [Indexed: 12/18/2022] Open
Abstract
In the past few decades, the prevalence of obesity and type 2 diabetes mellitus (T2DM), as well as older individuals at risk for Alzheimer’s disease (AD), has increased. While the consumption of diets high in fat (total and saturated) have been linked to increased risk of AD, diets rich in antioxidants, polyunsaturated fats, and omega-3 fatty acids are associated with decreased risk. Additionally, AD patients are at increased risk for developing T2DM. Recent research suggests that there are stronger similarities between AD and T2DM than have previously been considered. Here we review the neurocognitive and inflammatory effects of high-fat diet consumption, its relationship to AD, and the treatment potential of dietary interventions that may decrease risk of cognitive decline and other associated neuropathological changes, such as insulin resistance, oxidative stress, and chronic inflammatory processes.
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Affiliation(s)
- Jennifer M Walker
- Division of Diabetes, Endocrinology & Metabolism, Department of Medicine, Vanderbilt University, 2213 Garland Ave., Nashville, TN 37232, USA.
| | - Fiona E Harrison
- Division of Diabetes, Endocrinology & Metabolism, Department of Medicine, Vanderbilt University, 2213 Garland Ave., Nashville, TN 37232, USA.
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Cai Z, Xiao M, Chang L, Yan LJ. Role of insulin resistance in Alzheimer's disease. Metab Brain Dis 2015; 30:839-51. [PMID: 25399337 DOI: 10.1007/s11011-014-9631-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Accepted: 11/07/2014] [Indexed: 01/01/2023]
Abstract
A critical role of insulin resistance (IR) in Alzheimer's disease (AD) includes beta-amyloid (Aβ) production and accumulation, the formation of neurofibrillary tangles (NFTs), failure of synaptic transmission and neuronal degeneration. Aβ is sequentially cleavaged from APP by two proteolytic enzymes: β-secretase and γ-secretase. IR could regulate Aβ production via enhancing β- and γ-secretase activity. Meanwhile, IR induces oxidative stress and inflammation in the brain which contributes to Aβ and tau pathology. Aβ accumulation can enhance IR through Aβ-mediated inflammation and oxidative stress. IR is a possible linking between amyloid plaques and NFTs pathology via oxidative stress and neuroinflammation. Additionally, IR could disrupt acetylcholine activity, and accelerate axon degeneration and failures in axonal transport, and lead to cognitive impairment in AD. Preclinical and clinical studies have supported that insulin could be useful in the treatment of AD. Thus, an effective measure to inhibit IR may be a novel drug target in AD.
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Affiliation(s)
- Zhiyou Cai
- Department of Neurology, Renmin Hospital, Hubei University of Medicine, Shiyan Renmin Hospital, No. 39 Chaoyang Middle Road, Shiyan, 442000, Hubei Province, People's Republic of China,
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Banerji J. Asparaginase treatment side-effects may be due to genes with homopolymeric Asn codons (Review-Hypothesis). Int J Mol Med 2015; 36:607-26. [PMID: 26178806 PMCID: PMC4533780 DOI: 10.3892/ijmm.2015.2285] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 07/15/2015] [Indexed: 12/14/2022] Open
Abstract
The present treatment of childhood T-cell leukemias involves the systemic administration of prokary-otic L-asparaginase (ASNase), which depletes plasma Asparagine (Asn) and inhibits protein synthesis. The mechanism of therapeutic action of ASNase is poorly understood, as are the etiologies of the side-effects incurred by treatment. Protein expression from genes bearing Asn homopolymeric coding regions (N-hCR) may be particularly susceptible to Asn level fluctuation. In mammals, N-hCR are rare, short and conserved. In humans, misfunctions of genes encoding N-hCR are associated with a cluster of disorders that mimic ASNase therapy side-effects which include impaired glycemic control, dislipidemia, pancreatitis, compromised vascular integrity, and neurological dysfunction. This paper proposes that dysregulation of Asn homeostasis, potentially even by ASNase produced by the microbiome, may contribute to several clinically important syndromes by altering expression of N-hCR bearing genes. By altering amino acid abundance and modulating ribosome translocation rates at codon repeats, the microbiomic environment may contribute to genome decoding and to shaping the proteome. We suggest that impaired translation at poly Asn codons elevates diabetes risk and severity.
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Affiliation(s)
- Julian Banerji
- Center for Computational and Integrative Biology, MGH, Simches Research Center, Boston, MA 02114, USA
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43
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Wang Y, Wu L, Li J, Fang D, Zhong C, Chen JX, Yan SS. Synergistic exacerbation of mitochondrial and synaptic dysfunction and resultant learning and memory deficit in a mouse model of diabetic Alzheimer's disease. J Alzheimers Dis 2015; 43:451-63. [PMID: 25096625 DOI: 10.3233/jad-140972] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Diabetes is considered to be a risk factor in Alzheimer's disease (AD) pathogenesis. Although recent evidence indicates that diabetes exaggerates pathologic features of AD, the underlying mechanisms are not well understood. To determine whether mitochondrial perturbation is associated with the contribution of diabetes to AD progression, we characterized mouse models of streptozotocin (STZ)-induced type 1 diabetes and transgenic AD mouse models with diabetes. Brains from mice with STZ-induced diabetes revealed a significant increase of cyclophilin D (CypD) expression, reduced respiratory function, and decreased hippocampal long-term potentiation (LTP); these animals had impaired spatial learning and memory. Hyperglycemia exacerbated the upregulation of CypD, mitochondrial defects, synaptic injury, and cognitive dysfunction in the brains of transgenic AD mice overexpressing amyloid-β as shown by decreased mitochondrial respiratory complex I and IV enzyme activity and greatly decreased mitochondrial respiratory rate. Concomitantly, hippocampal LTP reduction and spatial learning and memory decline, two early pathologic indicators of AD, were enhanced in the brains of diabetic AD mice. Our results suggest that the synergistic interaction between effects of diabetes and AD on mitochondria may be responsible for brain dysfunction that is in common in both diabetes and AD.
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Affiliation(s)
- Yongfu Wang
- Department of Pharmacology and Toxicology, and Higuchi Bioscience Center, School of Pharmacy, University of Kansas, Lawrence, KS, USA
| | - Long Wu
- Department of Pharmacology and Toxicology, and Higuchi Bioscience Center, School of Pharmacy, University of Kansas, Lawrence, KS, USA
| | - Jianping Li
- Department of Pharmacology and Toxicology, and Higuchi Bioscience Center, School of Pharmacy, University of Kansas, Lawrence, KS, USA
| | - Du Fang
- Department of Pharmacology and Toxicology, and Higuchi Bioscience Center, School of Pharmacy, University of Kansas, Lawrence, KS, USA
| | - Changjia Zhong
- Department of Pharmacology and Toxicology, and Higuchi Bioscience Center, School of Pharmacy, University of Kansas, Lawrence, KS, USA College of Life Sciences, Beijing Normal University, Beijing, China
| | - John Xi Chen
- Department of Neurology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - Shirley ShiDu Yan
- Department of Pharmacology and Toxicology, and Higuchi Bioscience Center, School of Pharmacy, University of Kansas, Lawrence, KS, USA
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Huang S, Wang Y, Gan X, Fang D, Zhong C, Wu L, Hu G, Sosunov AA, McKhann GM, Yu H, Yan SS. Drp1-mediated mitochondrial abnormalities link to synaptic injury in diabetes model. Diabetes 2015; 64:1728-42. [PMID: 25412623 PMCID: PMC4407851 DOI: 10.2337/db14-0758] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 11/15/2014] [Indexed: 02/05/2023]
Abstract
Diabetes has adverse effects on the brain, especially the hippocampus, which is particularly susceptible to synaptic injury and cognitive dysfunction. The underlying mechanisms and strategies to rescue such injury and dysfunction are not well understood. Using a mouse model of type 2 diabetes (db/db mice) and a human neuronal cell line treated with high concentration of glucose, we demonstrate aberrant mitochondrial morphology, reduced ATP production, and impaired activity of complex I. These mitochondrial abnormalities are induced by imbalanced mitochondrial fusion and fission via a glycogen synthase kinase 3β (GSK3β)/dynamin-related protein-1 (Drp1)-dependent mechanism. Modulation of the Drp1 pathway or inhibition of GSK3β activity restores hippocampal long-term potentiation that is impaired in db/db mice. Our results point to a novel role for mitochondria in diabetes-induced synaptic impairment. Exploration of the mechanisms behind diabetes-induced synaptic deficit may provide a novel treatment for mitochondrial and synaptic injury in patients with diabetes.
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Affiliation(s)
- Shengbin Huang
- Department of Pharmacology & Toxicology and Higuchi Biosciences Center, School of Pharmacy, University of Kansas, Lawrence, KS State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yongfu Wang
- Department of Pharmacology & Toxicology and Higuchi Biosciences Center, School of Pharmacy, University of Kansas, Lawrence, KS
| | - Xueqi Gan
- Department of Pharmacology & Toxicology and Higuchi Biosciences Center, School of Pharmacy, University of Kansas, Lawrence, KS State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Du Fang
- Department of Pharmacology & Toxicology and Higuchi Biosciences Center, School of Pharmacy, University of Kansas, Lawrence, KS
| | - Changjia Zhong
- Department of Pharmacology & Toxicology and Higuchi Biosciences Center, School of Pharmacy, University of Kansas, Lawrence, KS
| | - Long Wu
- Department of Pharmacology & Toxicology and Higuchi Biosciences Center, School of Pharmacy, University of Kansas, Lawrence, KS
| | - Gang Hu
- Department of Pharmacology & Toxicology and Higuchi Biosciences Center, School of Pharmacy, University of Kansas, Lawrence, KS
| | - Alexander A Sosunov
- Department of Neurosurgery, College of Physicians and Surgeons, Columbia University, New York, NY
| | - Guy M McKhann
- Department of Neurosurgery, College of Physicians and Surgeons, Columbia University, New York, NY
| | - Haiyang Yu
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Shirley ShiDu Yan
- Department of Pharmacology & Toxicology and Higuchi Biosciences Center, School of Pharmacy, University of Kansas, Lawrence, KS
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Modulation of hippocampal neural plasticity by glucose-related signaling. Neural Plast 2015; 2015:657928. [PMID: 25977822 PMCID: PMC4419237 DOI: 10.1155/2015/657928] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 04/02/2015] [Accepted: 04/05/2015] [Indexed: 12/20/2022] Open
Abstract
Hormones and peptides involved in glucose homeostasis are emerging as important modulators of neural plasticity. In this regard, increasing evidence shows that molecules such as insulin, insulin-like growth factor-I, glucagon-like peptide-1, and ghrelin impact on the function of the hippocampus, which is a key area for learning and memory. Indeed, all these factors affect fundamental hippocampal properties including synaptic plasticity (i.e., synapse potentiation and depression), structural plasticity (i.e., dynamics of dendritic spines), and adult neurogenesis, thus leading to modifications in cognitive performance. Here, we review the main mechanisms underlying the effects of glucose metabolism on hippocampal physiology. In particular, we discuss the role of these signals in the modulation of cognitive functions and their potential implications in dysmetabolism-related cognitive decline.
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46
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Sowa J, Bobula B, Glombik K, Slusarczyk J, Basta-Kaim A, Hess G. Prenatal stress enhances excitatory synaptic transmission and impairs long-term potentiation in the frontal cortex of adult offspring rats. PLoS One 2015; 10:e0119407. [PMID: 25749097 PMCID: PMC4352064 DOI: 10.1371/journal.pone.0119407] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 01/13/2015] [Indexed: 11/26/2022] Open
Abstract
The effects of prenatal stress procedure were investigated in 3 months old male rats. Prenatally stressed rats showed depressive-like behavior in the forced swim test, including increased immobility, decreased mobility and decreased climbing. In ex vivo frontal cortex slices originating from prenatally stressed animals, the amplitude of extracellular field potentials (FPs) recorded in cortical layer II/III was larger, and the mean amplitude ratio of pharmacologically-isolated NMDA to the AMPA/kainate component of the field potential—smaller than in control preparations. Prenatal stress also resulted in a reduced magnitude of long-term potentiation (LTP). These effects were accompanied by an increase in the mean frequency, but not the mean amplitude, of spontaneous excitatory postsynaptic currents (sEPSCs) in layer II/III pyramidal neurons. These data demonstrate that stress during pregnancy may lead not only to behavioral disturbances, but also impairs the glutamatergic transmission and long-term synaptic plasticity in the frontal cortex of the adult offspring.
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Affiliation(s)
- Joanna Sowa
- Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Bartosz Bobula
- Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Katarzyna Glombik
- Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Joanna Slusarczyk
- Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Agnieszka Basta-Kaim
- Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
- * E-mail:
| | - Grzegorz Hess
- Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
- Institute of Zoology, Jagiellonian University, Krakow, Poland
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47
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Wang Y, Wang W, Li D, Li M, Wang P, Wen J, Liang M, Su B, Yin Y. IGF-1 alleviates NMDA-induced excitotoxicity in cultured hippocampal neurons against autophagy via the NR2B/PI3K-AKT-mTOR pathway. J Cell Physiol 2014; 229:1618-29. [PMID: 24604717 DOI: 10.1002/jcp.24607] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 03/05/2014] [Indexed: 12/30/2022]
Abstract
Insulin-like growth factor-1 (IGF-1) is a brain-specific multifunctional protein involved in neuronal polarity and axonal guidance. Mature IGF-1 triggers three enzymes, mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K), and phosphoinositide phospholipase C-γ (PLC-γ), which are its predominant downstream regulators. The PI3K-AKT signaling pathway is upstream of the mammalian target of rapamycin (mTOR), which is of great importance in the induction of autophagy. However, whether the neuroprotective effect of IGF-1 against excitotoxicity is mediated by autophagy through the PI3K/AKT/mTOR pathway remains to be elucidated. The induction of autophagy following NMDA treatment was determined by microtubule-associated protein light chain 3 (LC3) conversion and the result of this autophagy was assessed by monitoring the cleavage of caspase 3 in cultured hippocampal neurons. Cell viability was determined using MTT and LDH assay, and PI-staining was used to estimate the fate of autophagy and the protective effect of IGF-1. In addition, IGF-1 was found to decrease autophagy induced by NMDA using transmission electron microscopy and MDC staining. The protective effect of IGF-1 against autophagy was accompanied with up-regulation of phospho-AKT (p-AKT) and phospho-mTOR (p-mTOR), which was blocked by the inhibitor of PI3K. At the same time, the activation of NR2B resulting in the down-regulation of p-AKT and p-mTOR was blocked by IGF-1. Together, these data suggest that NMDA induces the autophagy, followed by apoptosis in cultured hippocampal neurons, and that IGF-1 can block this effect via inhibition of NR2B receptors and activation of the PI3K-AKT-mTOR pathway.
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Affiliation(s)
- Yansong Wang
- Department of Neurobiology and Beijing Institute for Brain Disorders, School of Basic Medical Sciences, Capital Medical University, Beijing, P.R. China; Department of Spine Surgery, Institute of Hard Tissue Development and Regeneration of Harbin Medical University, Second Affiliated Hospital of Harbin Medical University, Harbin, Hei Long Jiang Province, P.R. China
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Mehla J, Chauhan BC, Chauhan NB. Experimental induction of type 2 diabetes in aging-accelerated mice triggered Alzheimer-like pathology and memory deficits. J Alzheimers Dis 2014; 39:145-62. [PMID: 24121970 DOI: 10.3233/jad-131238] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Alzheimer's disease (AD) is an age-dependent neurodegenerative disease constituting ~95% of late-onset non-familial/sporadic AD, and only ~5% accounting for early-onset familial AD. Availability of a pertinent model representing sporadic AD is essential for testing candidate therapies. Emerging evidence indicates a causal link between diabetes and AD. People with diabetes are >1.5-fold more likely to develop AD. Senescence-accelerated mouse model (SAMP8) of accelerated aging displays many features occurring early in AD. Given the role played by diabetes in the pre-disposition of AD, and the utility of SAMP8 non-transgenic mouse model of accelerated aging, we examined if high fat diet-induced experimental type 2 diabetes in SAMP8 mice will trigger pathological aging of the brain. Results showed that compared to non-diabetic SAMP8 mice, diabetic SAMP8 mice exhibited increased cerebral amyloid-β, dysregulated tau-phosphorylating glycogen synthase kinase 3β, reduced synaptophysin immunoreactivity, and displayed memory deficits, indicating Alzheimer-like changes. High fat diet-induced type 2 diabetic SAMP8 mice may represent the metabolic model of AD.
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Affiliation(s)
- Jogender Mehla
- Neuroscience Research, Jesse Brown VA Medical Center, Chicago, IL, USA Department of Pediatrics, University of Illinois Hospital & Health Science System-Children's Hospital, University of Illinois at Chicago, Chicago, IL, USA
| | | | - Neelima B Chauhan
- Neuroscience Research, Jesse Brown VA Medical Center, Chicago, IL, USA Department of Pediatrics, University of Illinois Hospital & Health Science System-Children's Hospital, University of Illinois at Chicago, Chicago, IL, USA
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49
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White MF. IRS2 integrates insulin/IGF1 signalling with metabolism, neurodegeneration and longevity. Diabetes Obes Metab 2014; 16 Suppl 1:4-15. [PMID: 25200290 DOI: 10.1111/dom.12347] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Accepted: 05/27/2014] [Indexed: 12/11/2022]
Abstract
Understanding how metabolism and nutrient homeostasis integrates with life span and neurodegeneration is a complicated undertaking. Important inconsistencies have emerged recently regarding the role of insulin-like signalling and the progression of neurodegenerative disease. Insulin resistance and type 2 diabetes are associated with clinical Alzheimer's disease, whereas study in lower organisms shows that reduced insulin-like signalling slows the progressive neurodegeneration and increases life span. From a clinical perspective, compensatory hyperinsulinaemia to overcome systemic insulin resistance is thought to be a healthy goal, because it circumvents immediate catastrophic consequences of hyperglycaemia; however, study in flies, nematodes and mice indicate that excess insulin signalling can damage cellular function and accelerate ageing. Maintenance of the central nervous system (CNS) has particular importance for life span and metabolism. A conflict arises because reduced insulin/IGF1 signalling in the CNS is associated with longevity, but can dysregulate glucose and energy homeostasis, and promote overweight. Here, we explore how the genetic manipulation of insulin/IGF1 signalling system can influence systemic metabolism, life span and neurodegeneration.
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Affiliation(s)
- M F White
- Division of Endocrinology and the Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
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50
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Retinal neurodegenerative changes in the adult insulin receptor substrate-2 deficient mouse. Exp Eye Res 2014; 124:1-10. [PMID: 24792588 DOI: 10.1016/j.exer.2014.04.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 04/17/2014] [Accepted: 04/22/2014] [Indexed: 11/23/2022]
Abstract
Insulin receptor substrate-2 (Irs2) mediates peripheral insulin action and is essential for retinal health. Previous investigations have reported severe photoreceptor degeneration and abnormal visual function in Irs2-deficient mice. However, molecular changes in the Irs2(-)(/)(-) mouse retina have not been described. In this study, we examined retinal degenerative changes in neuronal and glial cells of adult (9- and 12-week old) Irs2(-)(/)(-) mice by immunohistochemistry. 9-week old Irs2(-)(/)(-) mice showed significant thinning of outer retinal layers, concomitant to Müller and microglial cell activation. Photoreceptor cells displayed different signs of degeneration, such as outer/inner segment atrophy, redistribution of rod- and cone-opsins and spatial disorganization of cone cells. This was accompanied by synaptic changes at the outer plexiform layer, including the retraction of rod-spherules, reduction of photoreceptor synaptic ribbons and synaptic remodeling in second order neurons (i.e. loss and sprouting of dendritic processes in rod bipolar and horizontal cells). By 12 weeks of age, the thickness of inner retinal layers was severely affected. Although inner plexiform layer stratification remained unchanged at this stage, rod bipolar cell axon terminals were significantly depleted. Significant loss of Brn3a(+) retinal ganglion cells occurred in 12-week old Irs2(-)(/)(-) mice, in contrast to younger ages. Adult Irs2(-)(/)(-) mice showed clear hallmarks of neurodegeneration and disruption of the inner retina with increasing age. Pharmacological stimulation of Irs2 signaling pathway may provide additional neuroprotection in certain degenerative retinopathies.
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