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Dewanjee S, Chakraborty P, Bhattacharya H, Chacko L, Singh B, Chaudhary A, Javvaji K, Pradhan SR, Vallamkondu J, Dey A, Kalra RS, Jha NK, Jha SK, Reddy PH, Kandimalla R. Altered glucose metabolism in Alzheimer's disease: Role of mitochondrial dysfunction and oxidative stress. Free Radic Biol Med 2022; 193:134-157. [PMID: 36206930 DOI: 10.1016/j.freeradbiomed.2022.09.032] [Citation(s) in RCA: 63] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/16/2022] [Accepted: 09/29/2022] [Indexed: 12/06/2022]
Abstract
Increasing evidence suggests that abnormal cerebral glucose metabolism is largely present in Alzheimer's disease (AD). The brain utilizes glucose as its main energy source and a decline in its metabolism directly reflects on brain function. Weighing on recent evidence, here we systematically assessed the aberrant glucose metabolism associated with amyloid beta and phosphorylated tau accumulation in AD brain. Interlink between insulin signaling and AD highlighted the involvement of the IRS/PI3K/Akt/AMPK signaling, and GLUTs in the disease progression. While shedding light on the mitochondrial dysfunction in the defective glucose metabolism, we further assessed functional consequences of AGEs (advanced glycation end products) accumulation, polyol activation, and other contributing factors including terminal respiration, ROS (reactive oxygen species), mitochondrial permeability, PINK1/parkin defects, lysosome-mitochondrial crosstalk, and autophagy/mitophagy. Combined with the classic plaque and tangle pathologies, glucose hypometabolism with acquired insulin resistance and mitochondrial dysfunction potentiate these factors to exacerbate AD pathology. To this end, we further reviewed AD and DM (diabetes mellitus) crosstalk in disease progression. Taken together, the present work discusses the emerging role of altered glucose metabolism, contributing impact of insulin signaling, and mitochondrial dysfunction in the defective cerebral glucose utilization in AD.
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Affiliation(s)
- Saikat Dewanjee
- Advanced Pharmacognosy Research Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, 700 032, West Bengal, India
| | - Pratik Chakraborty
- Advanced Pharmacognosy Research Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, 700 032, West Bengal, India
| | - Hiranmoy Bhattacharya
- Advanced Pharmacognosy Research Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, 700 032, West Bengal, India
| | - Leena Chacko
- BioAnalytical Lab, Meso Scale Discovery, 1601 Research Blvd, Rockville, MD, USA
| | - Birbal Singh
- ICAR-Indian Veterinary Research Institute (IVRI), Regional Station, Palampur, 176061, Himachal Pradesh, India
| | - Anupama Chaudhary
- Orinin-BioSystems, LE-52, Lotus Road 4, CHD City, Karnal, 132001, Haryana, India
| | - Kalpana Javvaji
- CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, India
| | | | | | - Abhijit Dey
- Department of Life Sciences, Presidency University, Kolkata, 700073, India
| | - Rajkumar Singh Kalra
- Immune Signal Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, 9040495, Japan
| | - Niraj Kumar Jha
- Department of Biotechnology, School of Engineering & Technology (SET), Sharda University, UP, 201310, India; Department of Biotechnology Engineering and Food Technology, Chandigarh University, Mohali, 140413, India; Department of Biotechnology, School of Applied & Life Sciences (SALS), Uttaranchal University, Dehradun, 248007, India
| | - Saurabh Kumar Jha
- Department of Biotechnology, School of Engineering & Technology (SET), Sharda University, UP, 201310, India; Department of Biotechnology Engineering and Food Technology, Chandigarh University, Mohali, 140413, India; Department of Biotechnology, School of Applied & Life Sciences (SALS), Uttaranchal University, Dehradun, 248007, India
| | - P Hemachandra Reddy
- Internal Medicine Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Neuroscience & Pharmacology, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Neurology Departments School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Public Health Department of Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Department of Speech, Language and Hearing Sciences, School Health Professions, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Ramesh Kandimalla
- CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, India; Department of Biochemistry, Kakatiya Medical College, Warangal, India.
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2
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Brain Glucose Transporters: Role in Pathogenesis and Potential Targets for the Treatment of Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms22158142. [PMID: 34360906 PMCID: PMC8348194 DOI: 10.3390/ijms22158142] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 07/06/2021] [Accepted: 07/28/2021] [Indexed: 12/16/2022] Open
Abstract
The most common cause of dementia, especially in elderly people, is Alzheimer’s disease (AD), with aging as its main risk factor. AD is a multifactorial neurodegenerative disease. There are several factors increasing the risk of AD development. One of the main features of Alzheimer’s disease is impairment of brain energy. Hypometabolism caused by decreased glucose uptake is observed in specific areas of the AD-affected brain. Therefore, glucose hypometabolism and energy deficit are hallmarks of AD. There are several hypotheses that explain the role of glucose hypometabolism in AD, but data available on this subject are poor. Reduced transport of glucose into neurons may be related to decreased expression of glucose transporters in neurons and glia. On the other hand, glucose transporters may play a role as potential targets for the treatment of AD. Compounds such as antidiabetic drugs, agonists of SGLT1, insulin, siRNA and liposomes are suggested as therapeutics. Nevertheless, the suggested targets of therapy need further investigations.
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3
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Calsolaro V, Bottari M, Coppini G, Lemmi B, Monzani F. Endocrine dysfunction and cognitive impairment. Minerva Endocrinol (Torino) 2021; 46:335-349. [PMID: 33435644 DOI: 10.23736/s2724-6507.20.03295-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Dementia is a highly prevalent chronic disease among the older population, affecting more than 50 million people worldwide and representing a huge healthcare, social and economic burden. Dementia, and in particular Alzheimer's disease, prevalence is expected to raise within the next few years. Unfortunately, no disease-modifying therapies are available so far, despite a plethora of clinical trials targeting the hallmarks of Alzheimer's disease. Given these premises, it appears crucial to address not only the neuropathological correlates of the disease, but also the modifiable risk factors. Among them, evidence suggest a role of the endocrine system not only in the brain development, but also in the maintenance of its health, having neurotrophic, antioxidant and metabolic functions crucial for the cognitive abilities. This review focuses on the evidence evaluating the impact of the endocrine systems, in particular thyroid function, insulin resistance, parathyroid hormone, vitamin D and sexual hormones on cognitive status. Results from epidemiological, preclinical and some clinical studies demonstrated the link between thyroid, parathyroid hormone and vitamin D and cognitive status, between diabetes, and insulin resistance in particular, and dementia, between sexual and adrenal hormones, particularly estrogen variation at menopause, and cognitive decline. The growing interest on the modifiable risks factors of cognitive decline increased the knowledge about the complex interplay of endocrine systems and cognition, highlighting the need and the usefulness of a multidisciplinary approach to the prevention of a complex and devastating disease.
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Affiliation(s)
- Valeria Calsolaro
- Geriatrics Unit, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Pisa, Italy
| | - Marina Bottari
- Geriatrics Unit, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Pisa, Italy
| | - Giulia Coppini
- Geriatrics Unit, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Pisa, Italy
| | - Bianca Lemmi
- Geriatrics Unit, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Pisa, Italy
| | - Fabio Monzani
- Geriatrics Unit, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Pisa, Italy -
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Ferrari F, Moretti A, Villa RF. The treament of hyperglycemia in acute ischemic stroke with incretin-based drugs. Pharmacol Res 2020; 160:105018. [PMID: 32574826 DOI: 10.1016/j.phrs.2020.105018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 05/21/2020] [Accepted: 06/10/2020] [Indexed: 12/14/2022]
Abstract
Stroke is a major cause of mortality and morbidity worldwide. Considerable experimental and clinical evidence suggests that both diabetes mellitus (DM) and post-stroke hyperglycemia are associated with increased mortality rate and worsened clinical conditions in acute ischemic stroke (AIS) patients. Insulin treatment does not seem to provide convincing benefits for these patients, therefore prompting a change of strategy. The selective agonists of Glucagon-Like Peptide-1 Receptors (GLP-1Ras) and the Inhibitors of Dipeptidyl Peptidase-IV (DPP-IVIs, gliptins) are two newer classes of glucose-lowering drugs used for the treatment of DM. This review examines in detail the rationale for their development and the physicochemical, pharmacokinetic and pharmacodynamic properties and clinical activities. Emphasis will be placed on their neuroprotective effects at cellular and molecular levels in experimental models of acute cerebral ischemia. In perspective, an adequate basis does exist for a novel therapeutic approach to hyperglycemia in AIS patients through the additive treatment with GLP-1Ras plus DPP-IVIs.
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Affiliation(s)
- Federica Ferrari
- Department of Advanced Diagnostic and Therapeutic Technologies, Section of Neuroradiology, ASST Grande Ospedale Metropolitano Niguarda, Piazza Ospedale Maggiore 3, 20162 Milano, Italy; Departments of Biology-Biotechnology and Chemistry, Laboratory of Pharmacology and Molecular Medicine of Central Nervous System, University of Pavia, Via Ferrata 9, 27100 Pavia, Italy
| | - Antonio Moretti
- Departments of Biology-Biotechnology and Chemistry, Laboratory of Pharmacology and Molecular Medicine of Central Nervous System, University of Pavia, Via Ferrata 9, 27100 Pavia, Italy
| | - Roberto Federico Villa
- Departments of Biology-Biotechnology and Chemistry, Laboratory of Pharmacology and Molecular Medicine of Central Nervous System, University of Pavia, Via Ferrata 9, 27100 Pavia, Italy.
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Mansur RB, Lee Y, Subramaniapillai M, Brietzke E, McIntyre RS. Cognitive dysfunction and metabolic comorbidities in mood disorders: A repurposing opportunity for glucagon-like peptide 1 receptor agonists? Neuropharmacology 2018; 136:335-342. [PMID: 29481915 DOI: 10.1016/j.neuropharm.2018.01.048] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 01/26/2018] [Accepted: 01/30/2018] [Indexed: 12/14/2022]
Abstract
Major depressive disorder and bipolar disorder are highly prevalent and disabling conditions. Cognition is considered a core domain of their psychopathology and a principle mediator of psychosocial impairment, disproportionately accounting for overall illness-associated costs. There are few interventions with replicated evidence of efficacy in treating cognitive deficits in mood disorders. Evidence also indicates that cognitive deficits are associated with obesity and involve significant impairment across multiple domains. Conversely, weight-loss interventions, such as physical exercise and bariatric surgery, have been shown to beneficially affect cognitive function. This convergent phenomenology suggests that currently available agents that target metabolic systems may also be capable of mitigating deficits in cognitive functions, and are, therefore, candidates for repurposing. The incretin glucagon-like peptide-1 (GLP-1) is a hormone secreted by intestinal epithelial cells. GLP-1 receptors (GLP-1R) are widely expressed in the central nervous system. Activation of GLP-1R leads to facilitation of glucose utilization and antiapoptotic effects in various organs. Pre-clinical trials have demonstrated significant neuroprotective effects of GLP-1, including protection from cell death, promotion of neuronal differentiation and proliferation; and facilitation of long-term potentiation. Liraglutide is a GLP-1R agonist that has been approved for the treatment of type 2 diabetes mellitus and obesity. Convergent preclinical and clinical evidence, including a proof-of-concept pilot study from group, has suggested that liraglutide may improve objective measures of cognitive function in adults with mood disorders. The safety and availability of GLP-1R agonists indicate that they are promising candidates for repurposing, and that they may be viable therapeutic options for mood disorders. This article is part of the Special Issue entitled 'Metabolic Impairment as Risk Factors for Neurodegenerative Disorders.'
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Affiliation(s)
- Rodrigo B Mansur
- Mood Disorders Psychopharmacology Unit (MDPU), University Health Network, University of Toronto, Toronto, Canada; University of Toronto, Toronto, Canada.
| | - Yena Lee
- Mood Disorders Psychopharmacology Unit (MDPU), University Health Network, University of Toronto, Toronto, Canada; Institute of Medical Science, University of Toronto, Canada
| | - Mehala Subramaniapillai
- Mood Disorders Psychopharmacology Unit (MDPU), University Health Network, University of Toronto, Toronto, Canada
| | - Elisa Brietzke
- Mood Disorders Psychopharmacology Unit (MDPU), University Health Network, University of Toronto, Toronto, Canada; Department of Psychiatry, Universidade Federal de Sao Paulo, Sao Paulo, Brazil
| | - Roger S McIntyre
- Mood Disorders Psychopharmacology Unit (MDPU), University Health Network, University of Toronto, Toronto, Canada; University of Toronto, Toronto, Canada
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6
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Lach G, Schellekens H, Dinan TG, Cryan JF. Anxiety, Depression, and the Microbiome: A Role for Gut Peptides. Neurotherapeutics 2018; 15:36-59. [PMID: 29134359 PMCID: PMC5794698 DOI: 10.1007/s13311-017-0585-0] [Citation(s) in RCA: 307] [Impact Index Per Article: 51.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The complex bidirectional communication between the gut and the brain is finely orchestrated by different systems, including the endocrine, immune, autonomic, and enteric nervous systems. Moreover, increasing evidence supports the role of the microbiome and microbiota-derived molecules in regulating such interactions; however, the mechanisms underpinning such effects are only beginning to be resolved. Microbiota-gut peptide interactions are poised to be of great significance in the regulation of gut-brain signaling. Given the emerging role of the gut-brain axis in a variety of brain disorders, such as anxiety and depression, it is important to understand the contribution of bidirectional interactions between peptide hormones released from the gut and intestinal bacteria in the context of this axis. Indeed, the gastrointestinal tract is the largest endocrine organ in mammals, secreting dozens of different signaling molecules, including peptides. Gut peptides in the systemic circulation can bind cognate receptors on immune cells and vagus nerve terminals thereby enabling indirect gut-brain communication. Gut peptide concentrations are not only modulated by enteric microbiota signals, but also vary according to the composition of the intestinal microbiota. In this review, we will discuss the gut microbiota as a regulator of anxiety and depression, and explore the role of gut-derived peptides as signaling molecules in microbiome-gut-brain communication. Here, we summarize the potential interactions of the microbiota with gut hormones and endocrine peptides, including neuropeptide Y, peptide YY, pancreatic polypeptide, cholecystokinin, glucagon-like peptide, corticotropin-releasing factor, oxytocin, and ghrelin in microbiome-to-brain signaling. Together, gut peptides are important regulators of microbiota-gut-brain signaling in health and stress-related psychiatric illnesses.
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Affiliation(s)
- Gilliard Lach
- APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Harriet Schellekens
- APC Microbiome Institute, University College Cork, Cork, Ireland
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
- Food for Health Ireland, University College Cork, Cork, Ireland
| | - Timothy G Dinan
- APC Microbiome Institute, University College Cork, Cork, Ireland
- Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland
| | - John F Cryan
- APC Microbiome Institute, University College Cork, Cork, Ireland.
- Food for Health Ireland, University College Cork, Cork, Ireland.
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7
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Nilsson M, Gjedde A, Brock B, Gejl M, Rungby J. The effects of incretin hormones on cerebral glucose metabolism in health and disease. Neuropharmacology 2017; 136:243-250. [PMID: 29274367 DOI: 10.1016/j.neuropharm.2017.12.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 12/14/2017] [Accepted: 12/18/2017] [Indexed: 12/25/2022]
Abstract
Incretin hormones, notably glucagon-like peptide-1 (GLP-1), are gluco-regulatory hormones with pleiotropic effects also in the central nervous system. Apart from a local production of GLP-1, systemic administration of the hormone has been shown to influence a number of cerebral pathologies, including neuroinflammation. Given the brains massive dependence on glucose as its major fuel, we here review the mechanistics of cerebral glucose transport and metabolism, focusing on the deleterious effects of both hypo- and hyperglycaemia. GLP-1, when administered as long-acting analogues or intravenously, appears to decrease transport of glucose in normoglycaemic conditions, without affecting the total cerebral glucose content. During hypoglycaemia this effect seems abated, whereas during hyperglycaemia GLP-1 regulates cerebral glucose metabolism towards stable levels resembling normoglycaemia. In Alzheimer's disease, a 6-month intervention with GLP-1 maintained cerebral glucose levels at baseline levels, contrasting the decline otherwise seen in Alzheimer's. Kinetic studies suggest blood-brain barrier (BBB) glucose transport as the key player in GLP-1 mediated effects on cerebral glucose metabolism. This article is part of the Special Issue entitled 'Metabolic Impairment as Risk Factors for Neurodegenerative Disorders.'
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Affiliation(s)
- Malin Nilsson
- Department of Endocrinology, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Albert Gjedde
- Department of Neuroscience, Panum Institute, University of Copenhagen, Copenhagen, Denmark; Departments of Clinical Research, and Department of Nuclear Medicine, University of Southern Denmark, Odense, Denmark
| | | | - Michael Gejl
- Department of Biomedicine, Aarhus University, Aarhus, Denmark; Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Jørgen Rungby
- Department of Endocrinology, Bispebjerg University Hospital, Copenhagen, Denmark.
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8
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Blood-Brain Glucose Transfer in Alzheimer's disease: Effect of GLP-1 Analog Treatment. Sci Rep 2017; 7:17490. [PMID: 29235507 PMCID: PMC5727512 DOI: 10.1038/s41598-017-17718-y] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 11/29/2017] [Indexed: 12/12/2022] Open
Abstract
There are fewer than normal glucose transporters at the blood-brain barrier (BBB) in Alzheimer’s disease (AD). When reduced expression of transporters aggravates the symptoms of AD, the transporters become a potential target of therapy. The incretin hormone GLP-1 prevents the decline of cerebral metabolic rate for glucose (CMRglc) in AD, and GLP-1 may serve to raise transporter numbers. We hypothesized that the GLP-1 analog liraglutide would prevent the decline of CMRglc in AD by raising blood-brain glucose transfer, depending on the duration of disease. We randomized 38 patients with AD to treatment with liraglutide (n = 18) or placebo (n = 20) for 6 months, and determined the blood-brain glucose transfer capacity (Tmax) in the two groups and a healthy age matched control group (n = 6). In both AD groups at baseline, Tmax estimates correlated inversely with the duration of AD, as did the estimates of CMRglc that in turn were positively correlated with cognition. The GLP-1 analog treatment, compared to placebo, highly significantly raised the Tmax estimates of cerebral cortex from 0.72 to 1.1 umol/g/min, equal to Tmax estimates in healthy volunteers. The result is consistent with the claim that GLP-1 analog treatment restores glucose transport at the BBB.
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9
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Keshava HB, Mowla A, Heinberg LJ, Schauer PR, Brethauer SA, Aminian A. Bariatric surgery may reduce the risk of Alzheimer's diseases through GLP-1 mediated neuroprotective effects. Med Hypotheses 2017; 104:4-9. [PMID: 28673587 DOI: 10.1016/j.mehy.2017.05.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 04/26/2017] [Accepted: 05/01/2017] [Indexed: 12/25/2022]
Abstract
Obesity and diabetes are associated with deficits in multiple neurocognitive domains and increased risk for dementia. Over the last two decades, there has been a significant increase in bariatric and metabolic surgery worldwide, driven by rising intertwined pandemics of obesity and diabetes, along with improvement in surgical techniques. Patients undergoing bariatric surgery achieve a significant decrease in their excess weight and a multitude of sequela associated with obesity, diabetes, and metabolic syndrome. Glucagon-like peptide 1 (GLP-1) is an intestinal peptide that has been implicated as one of the weight loss-independent mechanisms in how bariatric surgery affects type 2 diabetes. GLP-1 improves insulin secretion, inhibits apoptosis and induce pancreatic islet neogenesis, promotes satiety, and can regulate heart rate and blood pressure. Moreover, numerous studies have demonstrated potential neuroprotective and neurotrophic effects of GLP-1. Increased GLP-1 activity has been shown to increase cortical activity, promote neuronal growth, and inhibit neuronal degeneration. Specifically, in experimental studies on Alzheimer's disease, GLP-1 decreases amyloid deposition and neurofibrillary tangles. Furthermore, recent studies have also suggested that GLP-1 based therapies, new class of antidiabetic drugs, have favorable effects on neurodegenerative disorders such as Alzheimer's disease. We present a hypothesis that bariatric surgery can help delay or even prevent the onset of Alzheimer's disease in long-term by increasing the levels of GLP-1. This hypothesis has a potential for many studies from basic science projects to large population studies to fully understand the neurological and cognitive consequences of bariatric surgery and associated rise in GLP-1.
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Affiliation(s)
- Hari B Keshava
- Bariatric and Metabolic Institute, Department of General Surgery, Cleveland Clinic, Cleveland, OH, United States
| | - Ashkan Mowla
- Department of Neurology, Gates Vascular Institute, State University of New York (SUNY) at Buffalo, Buffalo, NY, United States
| | - Leslie J Heinberg
- Bariatric and Metabolic Institute, Department of General Surgery, Cleveland Clinic, Cleveland, OH, United States
| | - Philip R Schauer
- Bariatric and Metabolic Institute, Department of General Surgery, Cleveland Clinic, Cleveland, OH, United States
| | - Stacy A Brethauer
- Bariatric and Metabolic Institute, Department of General Surgery, Cleveland Clinic, Cleveland, OH, United States
| | - Ali Aminian
- Bariatric and Metabolic Institute, Department of General Surgery, Cleveland Clinic, Cleveland, OH, United States.
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10
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Muscogiuri G, DeFronzo RA, Gastaldelli A, Holst JJ. Glucagon-like Peptide-1 and the Central/Peripheral Nervous System: Crosstalk in Diabetes. Trends Endocrinol Metab 2017; 28:88-103. [PMID: 27871675 DOI: 10.1016/j.tem.2016.10.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 09/30/2016] [Accepted: 10/03/2016] [Indexed: 12/17/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) is released in response to meals and exerts important roles in the maintenance of normal glucose homeostasis. GLP-1 is also important in the regulation of neurologic and cognitive functions. These actions are mediated via neurons in the nucleus of the solitary tract that project to multiple regions expressing GLP-1 receptors (GLP-1Rs). Treatment with GLP-1R agonists (GLP-1-RAs) reduces ischemia-induced hyperactivity, oxidative stress, neuronal damage and apoptosis, cerebral infarct volume, and neurologic damage, after cerebral ischemia, in experimental models. Ongoing human trials report a neuroprotective effect of GLP-1-RAs in Alzheimer's and Parkinson's disease. In this review, we discuss the role of GLP-1 and GLP-1-RAs in the nervous system with focus on GLP-1 actions on appetite regulation, glucose homeostasis, and neuroprotection.
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Affiliation(s)
| | - Ralph A DeFronzo
- Diabetes Division, University of Texas Health Science Center, San Antonio, TX, USA
| | - Amalia Gastaldelli
- Diabetes Division, University of Texas Health Science Center, San Antonio, TX, USA; Institute of Clinical Physiology of the National Research Council (CNR), Pisa, Italy.
| | - Jens J Holst
- NNF Center for Basic Metabolic Research and Department of Biomedical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
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Rodell AB, O'Keefe G, Rowe CC, Villemagne VL, Gjedde A. Cerebral Blood Flow and Aβ-Amyloid Estimates by WARM Analysis of [ 11C]PiB Uptake Distinguish among and between Neurodegenerative Disorders and Aging. Front Aging Neurosci 2017; 8:321. [PMID: 28123366 PMCID: PMC5225115 DOI: 10.3389/fnagi.2016.00321] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 12/12/2016] [Indexed: 11/13/2022] Open
Abstract
Background: We report results of the novel Washout Allometric Reference Method (WARM) that uses estimates of cerebral blood flow and amyloid load from the same [11C]Pittsburgh Compound B ([11C]PiB) retention maps in brain to distinguish between patients with different forms dementia, including Alzheimer's disease, and healthy volunteers. The method introduces two approaches to the identification of brain pathology related to amyloid accumulation, (1) a novel analysis of amyloid binding based on the late washout of the tracer from brain tissue, and (2) the simultaneous estimation of absolute cerebral blood flow indices (sCBF) from the early accumulation of the tracer in brain tissue. Objective: We tested the hypothesis that a change of cerebral blood flow is correlated with the degree of tracer [11C]PiB retention, reflecting dendritic spine pathology and consequent inhibition of brain energy metabolism and reduction of blood flow by neurovascular coupling in neurodegenerative disorders, including Alzheimer's disease. Methods: Previously reported images of [11C]PiB retention in brain of 29 subjects with cognitive impairment or dementia [16 Alzheimer's Disease (AD), eight subjects with dementia with Lewy bodies (DLB), five patients with frontotemporal lobar degeneration (FTLD), five patients with mild cognitive impairment, and 29 age-matched healthy control subjects (HC)], underwent analysis of PiB delivery and retention by means of WARM for quantitation of [11C]PiB's binding potentials (BPND) and correlated surrogate cerebral blood flow (sCBF) estimates, based on the [11C]PiB images, compared to estimates by conventional Standard Uptake Value Ratio (SUVR) of [11C]PiB retention with cerebellum gray matter as reference. Receiver Operating Characteristics (ROC) revealed the power of discrimination among estimates. Results: For AD, the discriminatory power of [11C]PiB binding potential (BPND) by WARM exceeded the power of SUVR that in turn exceeded the power of sCBF estimates. Differences of [11C]PiB binding and sCBF measures between AD and HC both were highly significant (p < 0.001). For all the dementia groups as a whole, sCBF estimates revealed the greatest discrimination between the patient and HC groups. WARM resolves a major issue of amyloid load quantification with [11C]PiB in human brain by determining absolute sCBF and amyloid load measures from the same images. The two parameter approach provides key discriminary information in AD for which [11C]PiB traditionally is used, as well as for the distinct flow deficits in FTLD, and the marked parietal and occipital lobe flow deficits in DLB. Conclusion: We conclude that WARM yields estimates of two important variables that together discriminate among patients with dementia, including AD, and healthy volunteers, with ROC that are superior to conventional methods of analysis. The distinction between estimates of flow and amyloid load from the same dynamic emission tomograms provides valuable pathogenetic information.
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Affiliation(s)
- Anders B Rodell
- Centre for Clinical Research, University of Queensland, BrisbaneQLD, Australia; Department of Nuclear Medicine & PET-Centre, Aarhus University HospitalAarhus, Denmark
| | - Graeme O'Keefe
- Department of Molecular Imaging and Therapy, Centre for PET, Austin Health, Heidelberg VIC, Australia
| | - Christopher C Rowe
- Department of Molecular Imaging and Therapy, Centre for PET, Austin Health, Heidelberg VIC, Australia
| | - Victor L Villemagne
- Department of Molecular Imaging and Therapy, Centre for PET, Austin Health, Heidelberg VIC, Australia
| | - Albert Gjedde
- Department of Neuroscience and Pharmacology, University of CopenhagenCopenhagen, Denmark; Department of Neurology and Neurosurgery, McGill University, MontréalQC, Canada; Division of Nuclear Medicine, Department of Radiology and Radiological Science, Johns Hopkins University, BaltimoreMD, USA; Neurosciences Research Center, Tabriz University of Medical SciencesTabriz, Iran; Department of Clinical Medicine - Department of Nuclear Medicine, University of Southern DenmarkOdense, Denmark
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12
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DellaValle B, Brix GS, Brock B, Gejl M, Rungby J, Larsen A. Oral Administration of Sitagliptin Activates CREB and Is Neuroprotective in Murine Model of Brain Trauma. Front Pharmacol 2016; 7:450. [PMID: 27990119 PMCID: PMC5130988 DOI: 10.3389/fphar.2016.00450] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 11/10/2016] [Indexed: 12/21/2022] Open
Abstract
Introduction: Traumatic brain injury is a major cause of mortality and morbidity. We have previously shown that the injectable glucagon-like peptide-1 (GLP-1) analog, liraglutide, significantly improved the outcome in mice after severe traumatic brain injury (TBI). In this study we are interested in the effects of oral treatment of a different class of GLP-1 based therapy, dipeptidyl peptidase IV (DPP-IV) inhibition on mice after TBI. DPP-IV inhibitors reduce the degradation of endogenous GLP-1 and extend circulation of this protective peptide in the bloodstream. This class has yet to be investigated as a potential therapy for TBI. Methods: Mice were administrated once-daily 50 mg/kg of sitagliptin in a Nutella® ball or Nutella® alone throughout the study, beginning 2 days before severe trauma was induced with a stereotactic cryo-lesion. At 2 days post trauma, lesion size was determined. Brains were isolated for immunoblotting for assessment of selected biomarkers for pathology and protection. Results: Sitagliptin treatment reduced lesion size at day 2 post-injury by ~28% (p < 0.05). Calpain-driven necrotic tone was reduced ~2-fold in sitagliptin-treated brains (p < 0.001) and activation of the protective cAMP-response element binding protein (CREB) system was significantly more pronounced (~1.5-fold, p < 0.05). The CREB-regulated, mitochondrial antioxidant protein manganese superoxide dismutase (MnSOD) was increased in sitagliptin-treated mice (p < 0.05). Conversely, apoptotic tone (alpha-spectrin fragmentation, Bcl-2 levels) and the neuroinflammatory markers IL-6, and Iba-1 were not affected by treatment. Conclusions: This study shows, for the first time, that DPP-IV inhibition ameliorates both anatomical and biochemical consequences of TBI and activates CREB in the brain. Moreover, this work supports previous studies suggesting that the effect of GLP-1 analogs in models of brain damage relates to GLP-1 receptor stimulation in a dose-dependent manner.
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Affiliation(s)
- Brian DellaValle
- Department of Biomedicine/Pharmacology, Aarhus UniversityAarhus, Denmark; Centre of Medical Parasitology, Department of Clinical Microbiology, Copenhagen University HospitalCopenhagen, Denmark
| | - Gitte S Brix
- Department of Biomedicine/Pharmacology, Aarhus University Aarhus, Denmark
| | - Birgitte Brock
- Department of Biomedicine/Pharmacology, Aarhus UniversityAarhus, Denmark; Department of Clinical Biochemistry, Aarhus University HospitalAarhus, Denmark
| | - Michael Gejl
- Department of Biomedicine/Pharmacology, Aarhus UniversityAarhus, Denmark; Department of Clinical Biochemistry, Aarhus University HospitalAarhus, Denmark
| | - Jørgen Rungby
- Department of Biomedicine/Pharmacology, Aarhus UniversityAarhus, Denmark; Department of Endocrinology, Bispebjerg University HospitalCopenhagen, Denmark
| | - Agnete Larsen
- Department of Biomedicine/Pharmacology, Aarhus University Aarhus, Denmark
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DellaValle B, Brix GS, Brock B, Gejl M, Landau AM, Møller A, Rungby J, Larsen A. Glucagon-Like Peptide-1 Analog, Liraglutide, Delays Onset of Experimental Autoimmune Encephalitis in Lewis Rats. Front Pharmacol 2016; 7:433. [PMID: 27917122 PMCID: PMC5114298 DOI: 10.3389/fphar.2016.00433] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 10/31/2016] [Indexed: 12/23/2022] Open
Abstract
Introduction: Recent findings indicate that metabolic disturbances are involved in multiple sclerosis (MS) pathology and influence the susceptibility to treatment, directing attention toward anti-diabetic drugs such as metformin and pioglitazone. Liraglutide, a drug of the glucagon-like peptide-1 (GLP-1) family, is also anti-diabetic and weight-reducing and is, moreover, directly neuroprotective and anti-inflammatory in a broad spectrum of experimental models of brain disease. In this study we investigate the potential for this FDA-approved drug, liraglutide, as a treatment for MS by utilizing the experimental model, experimental autoimmune encephalitis (EAE). Methods: EAE was induced in 30 female Lewis rats that subsequently received twice-daily liraglutide (200 μg/kg s.c.) or saline. Healthy controls were included (saline, n = 6, liraglutide, n = 7). Clinical score and weight were assessed daily by blinded observers. Animals were killed at peak disease severity (day 11) or if exceeding humane endpoint (clinical score ≥4). Protein levels of manganese superoxide dismutase (MnSOD), amyloid precursor protein (APP), and glial fibrillary acidic protein (GFAP) were determined. Results: Liraglutide treatment delayed disease onset (group clinical score significantly >0) by 2 days and markedly reduced disease severity (median clinical score 2 vs. 5; p = 0.0003). Fourteen of 15 (93%) of vehicle-treated rats reached the humane endpoint (clinical score ≥4) by day 11 compared to 5 of 15 (33%) of liraglutide-treated rats (p = 0.0004). Liraglutide substantially increased the mitochondrial antioxidant MnSOD (p < 0.01) and reduced the neurodegenerative marker APP (p = 0.036) in the brain. GFAP levels were not significantly changed with drug treatment (p = 0.09). Conclusion: We demonstrate, for the first time, that liraglutide treatment delays onset of EAE in Lewis rats and is associated with improved protective capacity against oxidative stress. These data suggest GLP-1 receptor agonists should be investigated further as a potential therapy for MS.
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Affiliation(s)
- Brian DellaValle
- Department of Biomedicine/Pharmacology, Aarhus UniversityAarhus, Denmark; Centre of Medical Parasitology, Department of Clinical Microbiology, Copenhagen University HospitalCopenhagen, Denmark
| | - Gitte S Brix
- Department of Biomedicine/Pharmacology, Aarhus University Aarhus, Denmark
| | - Birgitte Brock
- Department of Biomedicine/Pharmacology, Aarhus UniversityAarhus, Denmark; Department of Clinical Biochemistry and Department of Clinical Medicine, Aarhus University Hospital, Aarhus UniversityAarhus, Denmark
| | - Michael Gejl
- Department of Biomedicine/Pharmacology, Aarhus UniversityAarhus, Denmark; Department of Clinical Biochemistry and Department of Clinical Medicine, Aarhus University Hospital, Aarhus UniversityAarhus, Denmark
| | - Anne M Landau
- Department of Nuclear Medicine and PET Center, Aarhus UniversityAarhus, Denmark; Centre For Functionally Integrative Neuroscience, Aarhus UniversityAarhus, Denmark
| | - Arne Møller
- Department of Nuclear Medicine and PET Center, Aarhus UniversityAarhus, Denmark; Centre For Functionally Integrative Neuroscience, Aarhus UniversityAarhus, Denmark
| | - Jørgen Rungby
- Department of Biomedicine/Pharmacology, Aarhus UniversityAarhus, Denmark; Department of Endocrinology, Bispebjerg University HospitalCopenhagen, Denmark
| | - Agnete Larsen
- Department of Biomedicine/Pharmacology, Aarhus University Aarhus, Denmark
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Hansen HH, Fabricius K, Barkholt P, Niehoff ML, Morley JE, Jelsing J, Pyke C, Knudsen LB, Farr SA, Vrang N. The GLP-1 Receptor Agonist Liraglutide Improves Memory Function and Increases Hippocampal CA1 Neuronal Numbers in a Senescence-Accelerated Mouse Model of Alzheimer's Disease. J Alzheimers Dis 2016; 46:877-88. [PMID: 25869785 PMCID: PMC4878312 DOI: 10.3233/jad-143090] [Citation(s) in RCA: 122] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Recent studies indicate that glucagon-like peptide 1 (GLP-1) receptor agonists, currently used in the management of type 2 diabetes, exhibit neurotrophic and neuroprotective effects in amyloid-β (Aβ) toxicity models of Alzheimer’s disease (AD). We investigated the potential pro-cognitive and neuroprotective effects of the once-daily GLP-1 receptor agonist liraglutide in senescence-accelerated mouse prone 8 (SAMP8) mice, a model of age-related sporadic AD not dominated by amyloid plaques. Six-month-old SAMP8 mice received liraglutide (100 or 500 μg/kg/day, s.c.) or vehicle once daily for 4 months. Vehicle-dosed age-matched 50% back-crossed as well as untreated young (4-month-old) SAMP8 mice were used as control groups for normal memory function. Vehicle-dosed 10-month-old SAMP8 mice showed significant learning and memory retention deficits in an active-avoidance T-maze, as compared to both control groups. Also, 10-month-old SAMP8 mice displayed no immunohistological signatures of amyloid-β plaques or hyperphosphorylated tau, indicating the onset of cognitive deficits prior to deposition of amyloid plaques and neurofibrillary tangles in this AD model. Liraglutide significantly increased memory retention and total hippocampal CA1 pyramidal neuron numbers in SAMP8 mice, as compared to age-matched vehicle-dosed SAMP8 mice. In conclusion, liraglutide delayed or partially halted the progressive decline in memory function associated with hippocampal neuronal loss in a mouse model of pathological aging with characteristics of neurobehavioral and neuropathological impairments observed in early-stage sporadic AD.
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Affiliation(s)
| | | | | | | | - John E Morley
- St. Louis University, Division of Geriatrics, St. Louis, MO, USA.,St. Louis University School of Medicine, Division of Endocrinology, St. Louis University, St. Louis, MO, USA
| | | | - Charles Pyke
- Diabetes Research, Novo Nordisk A/S, Maaloev, Denmark
| | | | - Susan A Farr
- St. Louis University, Division of Geriatrics, St. Louis, MO, USA.,Research and Development, Veterans Affairs Medical Center, St. Louis, MO, USA
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15
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Gejl M, Gjedde A, Egefjord L, Møller A, Hansen SB, Vang K, Rodell A, Brændgaard H, Gottrup H, Schacht A, Møller N, Brock B, Rungby J. In Alzheimer's Disease, 6-Month Treatment with GLP-1 Analog Prevents Decline of Brain Glucose Metabolism: Randomized, Placebo-Controlled, Double-Blind Clinical Trial. Front Aging Neurosci 2016; 8:108. [PMID: 27252647 PMCID: PMC4877513 DOI: 10.3389/fnagi.2016.00108] [Citation(s) in RCA: 265] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 04/26/2016] [Indexed: 12/11/2022] Open
Abstract
In animal models, the incretin hormone GLP-1 affects Alzheimer’s disease (AD). We hypothesized that treatment with GLP-1 or an analog of GLP-1 would prevent accumulation of Aβ and raise, or prevent decline of, glucose metabolism (CMRglc) in AD. In this 26-week trial, we randomized 38 patients with AD to treatment with the GLP-1 analog liraglutide (n = 18), or placebo (n = 20). We measured Aβ load in brain with tracer [11C]PIB (PIB), CMRglc with [18F]FDG (FDG), and cognition with the WMS-IV scale (ClinicalTrials.gov NCT01469351). The PIB binding increased significantly in temporal lobe in placebo and treatment patients (both P = 0.04), and in occipital lobe in treatment patients (P = 0.04). Regional and global increases of PIB retention did not differ between the groups (P ≥ 0.38). In placebo treated patients CMRglc declined in all regions, significantly so by the following means in precuneus (P = 0.009, 3.2 μmol/hg/min, 95% CI: 5.45; 0.92), and in parietal (P = 0.04, 2.1 μmol/hg/min, 95% CI: 4.21; 0.081), temporal (P = 0.046, 1.54 μmol/hg/min, 95% CI: 3.05; 0.030), and occipital (P = 0.009, 2.10 μmol/hg/min, 95% CI: 3.61; 0.59) lobes, and in cerebellum (P = 0.04, 1.54 μmol/hg/min, 95% CI: 3.01; 0.064). In contrast, the GLP-1 analog treatment caused a numerical but insignificant increase of CMRglc after 6 months. Cognitive scores did not change. We conclude that the GLP-1 analog treatment prevented the decline of CMRglc that signifies cognitive impairment, synaptic dysfunction, and disease evolution. We draw no firm conclusions from the Aβ load or cognition measures, for which the study was underpowered.
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Affiliation(s)
- Michael Gejl
- Institute of Biomedicine, Aarhus UniversityAarhus, Denmark; Department of Nuclear Medicine and PET Center, Aarhus University HospitalAarhus, Denmark
| | - Albert Gjedde
- Department of Nuclear Medicine and PET Center, Aarhus University HospitalAarhus, Denmark; Department of Neuroscience and Pharmacology, University of CopenhagenCopenhagen, Denmark
| | - Lærke Egefjord
- Institute of Biomedicine, Aarhus UniversityAarhus, Denmark; Department of Nuclear Medicine and PET Center, Aarhus University HospitalAarhus, Denmark
| | - Arne Møller
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital Aarhus, Denmark
| | - Søren B Hansen
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital Aarhus, Denmark
| | - Kim Vang
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital Aarhus, Denmark
| | - Anders Rodell
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital Aarhus, Denmark
| | - Hans Brændgaard
- Dementia Clinic, Department of Neurology, Aarhus University Hospital Aarhus, Denmark
| | - Hanne Gottrup
- Dementia Clinic, Department of Neurology, Aarhus University Hospital Aarhus, Denmark
| | - Anna Schacht
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital Aarhus, Denmark
| | - Niels Møller
- Department of Endocrinology, Aarhus University Hospital Aarhus, Denmark
| | - Birgitte Brock
- Institute of Biomedicine, Aarhus UniversityAarhus, Denmark; Department of Clinical Biochemistry, Aarhus University HospitalAarhus, Denmark
| | - Jørgen Rungby
- Institute of Biomedicine, Aarhus UniversityAarhus, Denmark; Center for Diabetes Research and Department of Clinical Pharmacology, Copenhagen University Hospital Gentofte and RigshospitaletCopenhagen, Denmark
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Shibata E, Aoki K, Tajima K, Taguri M, Terauchi Y. Comparison of efficacy and safety of taking miglitol dissolved in water during a meal and taking a miglitol tablet just before a meal in patients with type 2 diabetes. Expert Opin Pharmacother 2016; 17:889-94. [DOI: 10.1517/14656566.2016.1159297] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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17
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Hansen HH, Barkholt P, Fabricius K, Jelsing J, Terwel D, Pyke C, Knudsen LB, Vrang N. The GLP-1 receptor agonist liraglutide reduces pathology-specific tau phosphorylation and improves motor function in a transgenic hTauP301L mouse model of tauopathy. Brain Res 2016; 1634:158-170. [DOI: 10.1016/j.brainres.2015.12.052] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 12/18/2015] [Accepted: 12/22/2015] [Indexed: 01/10/2023]
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Novel GLP-1 (Glucagon-Like Peptide-1) Analogues and Insulin in the Treatment for Alzheimer's Disease and Other Neurodegenerative Diseases. CNS Drugs 2015; 29:1023-39. [PMID: 26666230 DOI: 10.1007/s40263-015-0301-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The link between diabetes mellitus and Alzheimer's disease (AD) has been known for the last few decades. Since insulin and insulin receptors are known to be present in the brain, the downstream signalling as well as the effect of hyperinsulinemia have been extensively studied in both AD and Parkinson's disease. Glucagon-like peptide-1 (GLP-1) is a hormone belonging to the incretin family, and its receptors (GLP-1Rs) can be found in pancreatic cells and in vascular endothelium. Interestingly, GLP-1Rs are found in the neuronal cell body and dendrites in the central nervous system (CNS), in particular in the hypothalamus, hippocampus, cerebral cortex and olfactory bulb. Several studies have shown the importance of both insulin and GLP-1 signalling on cognitive function, and many preclinical studies have been performed to evaluate the potential protective role of GLP-1 on the brain. Here we review the underlying mechanism of insulin and GLP-1 signalling in the CNS, as well as the preclinical data for the use of GLP-1 analogues such as liraglutide, exenatide and lixisenatide in neurodegenerative diseases.
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Candeias EM, Sebastião IC, Cardoso SM, Correia SC, Carvalho CI, Plácido AI, Santos MS, Oliveira CR, Moreira PI, Duarte AI. Gut-brain connection: The neuroprotective effects of the anti-diabetic drug liraglutide. World J Diabetes 2015; 6:807-827. [PMID: 26131323 PMCID: PMC4478577 DOI: 10.4239/wjd.v6.i6.807] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 01/30/2015] [Accepted: 05/18/2015] [Indexed: 02/05/2023] Open
Abstract
Long-acting glucagon-like peptide-1 (GLP-1) analogues marketed for type 2 diabetes (T2D) treatment have been showing positive and protective effects in several different tissues, including pancreas, heart or even brain. This gut secreted hormone plays a potent insulinotropic activity and an important role in maintaining glucose homeostasis. Furthermore, growing evidences suggest the occurrence of several commonalities between T2D and neurodegenerative diseases, insulin resistance being pointed as a main cause for cognitive decline and increased risk to develop dementia. In this regard, it has also been suggested that stimulation of brain insulin signaling may have a protective role against cognitive deficits. As GLP-1 receptors (GLP-1R) are expressed throughout the central nervous system and GLP-1 may cross the blood-brain-barrier, an emerging hypothesis suggests that they may be promising therapeutic targets against brain dysfunctional insulin signaling-related pathologies. Importantly, GLP-1 actions depend not only on the direct effect mediated by its receptor activation, but also on the gut-brain axis involving an exchange of signals between both tissues via the vagal nerve, thereby regulating numerous physiological functions (e.g., energy homeostasis, glucose-dependent insulin secretion, as well as appetite and weight control). Amongst the incretin/GLP-1 mimetics class of anti-T2D drugs with an increasingly described neuroprotective potential, the already marketed liraglutide emerged as a GLP-1R agonist highly resistant to dipeptidyl peptidase-4 degradation (thereby having an increased half-life) and whose systemic GLP-1R activity is comparable to that of native GLP-1. Importantly, several preclinical studies showed anti-apoptotic, anti-inflammatory, anti-oxidant and neuroprotective effects of liraglutide against T2D, stroke and Alzheimer disease (AD), whereas several clinical trials, demonstrated some surprising benefits of liraglutide on weight loss, microglia inhibition, behavior and cognition, and in AD biomarkers. Herein, we discuss the GLP-1 action through the gut-brain axis, the hormone’s regulation of some autonomic functions and liraglutide’s neuroprotective potential.
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Gejl M, Starup-Linde J, Scheel-Thomsen J, Gregersen S, Vestergaard P. Risk of cardiovascular disease: The effects of diabetes and anti-diabetic drugs — A nested case–control study. Int J Cardiol 2015; 178:292-6. [DOI: 10.1016/j.ijcard.2014.11.096] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 10/24/2014] [Accepted: 11/10/2014] [Indexed: 11/28/2022]
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