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Reitz NL, Nunes PT, Savage LM. Adolescent alcohol exposure alters age-related progression of behavioral and neurotrophic dysfunction in the TgF344-AD model in a sex-specific manner. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.17.603911. [PMID: 39091885 PMCID: PMC11291002 DOI: 10.1101/2024.07.17.603911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/04/2024]
Abstract
Alzheimer's Disease (AD) and heavy alcohol use are widely prevalent and lead to brain pathology. Both alcohol-related brain damage (ABRD) and AD result in cholinergic dysfunction, reductions in hippocampal neurogenesis, and the emergence of hippocampal-dependent cognitive impairments. It is still unknown how ARBD caused during a critical developmental timepoint, such as adolescence, interacts with AD-related pathologies to accelerate disease progression later in life. The current study utilized a longitudinal design to characterize behavioral and pathological changes in a transgenic rat model of AD (TgF344-AD) following adolescent intermittent ethanol (AIE) exposure. We found that AIE accelerates cognitive decline associated with AD transgenes in female rats at 6 months of age, and male AD-rats are impaired on spatial navigation by 3-months with no additional deficits due to AIE exposure. Protein levels of various AD-pathological markers were analyzed in the dorsal and ventral hippocampus of male and female rats. The data suggests that AIE-induced alterations of the tropomyosin-related kinase A receptor (TrkA) / p75 neurotrophin receptor (p75NTR) ratio creates a brain that is vulnerable to age- and AD-related pathologies, which leads to an acceleration of cognitive decline, particularly in female rats.
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d’Orchymont F, Narvaez A, Raymond R, Sachdev P, Charil A, Krause S, Vasdev N. In vitro evaluation of PET radiotracers for imaging synaptic density, the acetylcholine transporter, AMPA-tarp-γ8 and muscarinic M4 receptors in Alzheimer's disease. AMERICAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING 2024; 14:1-12. [PMID: 38500748 PMCID: PMC10944377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 02/04/2024] [Indexed: 03/20/2024]
Abstract
Several therapeutics and biomarkers that target Alzheimer's disease (AD) are under development. Our clinical positron emission tomography (PET) research programs are interested in six radiopharmaceuticals to image patients with AD and related dementias, specifically [11C]UCB-J and [18F]SynVesT-1 for synaptic vesicle glycoprotein 2A as a marker of synaptic density, two vesicular acetylcholine transporter PET radiotracers: [18F]FEOBV and [18F]VAT, as well as the transmembrane AMPA receptor regulatory protein (TARP)-γ8 tracer, [18F]JNJ-64511070, and the muscarinic acetylcholine receptor (mAChR) M4 tracer [11C]MK-6884. The goal of this study was to compare all six radiotracers (labeled with tritium or 18F) by measuring their density variability in pathologically diagnosed cases of AD, mild cognitive impairment (MCI) and normal healthy volunteer (NHV) human brains, using thin-section in vitro autoradiography (ARG). Region of interest analysis was used to quantify radioligand binding density and determine whether the radioligands provide a signal-to-noise ratio optimal for showing changes in binding. Our preliminary study confirmed that all six radiotracers show specific binding in MCI and AD. An expected decrease in their respective target density in human AD hippocampus tissues compared to NHV was observed with [3H]UCB-J, [3H]SynVesT-1, [3H]JNJ-64511070, and [3H]MK-6884. This preliminary study will be used to guide human PET imaging of SV2A, TARP-γ8 and the mAChR M4 subtype for imaging in AD and related dementias.
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Affiliation(s)
- Faustine d’Orchymont
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH)Toronto, ON, Canada
| | - Andrea Narvaez
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH)Toronto, ON, Canada
- Enigma Biomedical Group, Inc.Toronto, ON, Canada
| | - Roger Raymond
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH)Toronto, ON, Canada
| | | | | | | | - Neil Vasdev
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH)Toronto, ON, Canada
- Department of Psychiatry, University of TorontoToronto, ON, Canada
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Cools R, Kerkhofs K, Leitao RCF, Bormans G. Preclinical Evaluation of Novel PET Probes for Dementia. Semin Nucl Med 2023; 53:599-629. [PMID: 37149435 DOI: 10.1053/j.semnuclmed.2023.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 03/24/2023] [Indexed: 05/08/2023]
Abstract
The development of novel PET imaging agents that selectively bind specific dementia-related targets can contribute significantly to accurate, differential and early diagnosis of dementia causing diseases and support the development of therapeutic agents. Consequently, in recent years there has been a growing body of literature describing the development and evaluation of potential new promising PET tracers for dementia. This review article provides a comprehensive overview of novel dementia PET probes under development, classified by their target, and pinpoints their preclinical evaluation pathway, typically involving in silico, in vitro and ex/in vivo evaluation. Specific target-associated challenges and pitfalls, requiring extensive and well-designed preclinical experimental evaluation assays to enable successful clinical translation and avoid shortcomings observed for previously developed 'well-established' dementia PET tracers are highlighted in this review.
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Affiliation(s)
- Romy Cools
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Kobe Kerkhofs
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium; NURA, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium
| | - Renan C F Leitao
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Guy Bormans
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium.
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Li Z, Liu H, Han W, Zhu S, Liu C. NMN Alleviates NP-Induced Learning and Memory Impairment Through SIRT1 Pathway in PC-12 Cell. Mol Neurobiol 2023; 60:2871-2883. [PMID: 36745337 DOI: 10.1007/s12035-023-03251-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 01/28/2023] [Indexed: 02/07/2023]
Abstract
Nonylphenol (NP) is widely used in the chemical industry; it accumulates in organisms through environmental contamination and causes learning memory impairment. Nicotinamide mononucleotide (NMN) has been found to have a positive effect on the treatment of central nervous-related diseases. This study aimed to investigate the protective effect of NMN on NP-induced learning memory-related impairment in vitro and to further identify the underlying mechanisms. The results showed that NP induced oxidative stress and impaired the cholinergic system, 5-HT system in PC-12 cells. NMN alleviated NP-induced learning and memory impairment at the molecular level through alleviating oxidative stress and protective effects on the 5-HT system and cholinergic system. The 50 μM NP group significantly reduced the NAD+ content, and the relative expression of SIRT1, PGC-1α, Nrf2, MAOA, BDNF, and p-TrkB were significantly downregulated. Co-treatment of NMN with NP significantly reduced oxidative stress, improved the homeostasis of 5-HT and cholinergic system, enhanced the intracellular NAD+ content, and significantly upregulated the expression of SIRT1 pathway proteins. SIRT1 inhibitors reduced the expression of SIRT1 pathway-related proteins, which implied the impairment of learning and memory by NP and the protective effect of NMN might be achieved through the SIRT1-mediated PGC-1α/MAOA/BDNF signaling pathway. Overall, this study not only help us to understand the toxic mechanism of NP on learning memory impairment in vitro, but also have important reference significance to further explore the health care value of NMN and promote the development of related functional foods.
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Affiliation(s)
- Zhongyi Li
- College of Food Science, South China Agricultural University, 483#, Wu-Shan Ave., Tian-He District, Guangzhou, 510642, China
- Guangdong Provincial Key Laboratory of Food Quality and Safety, Guangzhou, 510642, China
| | - Huan Liu
- College of Food Science, South China Agricultural University, 483#, Wu-Shan Ave., Tian-He District, Guangzhou, 510642, China
- Guangdong Provincial Key Laboratory of Food Quality and Safety, Guangzhou, 510642, China
| | - Wenna Han
- College of Food Science, South China Agricultural University, 483#, Wu-Shan Ave., Tian-He District, Guangzhou, 510642, China
- Guangdong Provincial Key Laboratory of Food Quality and Safety, Guangzhou, 510642, China
| | - Siyu Zhu
- College of Food Science, South China Agricultural University, 483#, Wu-Shan Ave., Tian-He District, Guangzhou, 510642, China
- Guangdong Provincial Key Laboratory of Food Quality and Safety, Guangzhou, 510642, China
| | - Chunhong Liu
- College of Food Science, South China Agricultural University, 483#, Wu-Shan Ave., Tian-He District, Guangzhou, 510642, China.
- Guangdong Provincial Key Laboratory of Food Quality and Safety, Guangzhou, 510642, China.
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Iliyasu MO, Musa SA, Oladele SB, Iliya AI. Amyloid-beta aggregation implicates multiple pathways in Alzheimer's disease: Understanding the mechanisms. Front Neurosci 2023; 17:1081938. [PMID: 37113145 PMCID: PMC10128090 DOI: 10.3389/fnins.2023.1081938] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 03/13/2023] [Indexed: 04/29/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative condition characterized by tau pathology and accumulations of neurofibrillary tangles (NFTs) along with amyloid-beta (Aβ). It has been associated with neuronal damage, synaptic dysfunction, and cognitive deficits. The current review explained the molecular mechanisms behind the implications of Aβ aggregation in AD via multiple events. Beta (β) and gamma (γ) secretases hydrolyzed amyloid precursor protein (APP) to produce Aβ, which then clumps together to form Aβ fibrils. The fibrils increase oxidative stress, inflammatory cascade, and caspase activation to cause hyperphosphorylation of tau protein into neurofibrillary tangles (NFTs), which ultimately lead to neuronal damage. Acetylcholine (Ach) degradation is accelerated by upstream regulation of the acetylcholinesterase (AChE) enzyme, which leads to a deficiency in neurotransmitters and cognitive impairment. There are presently no efficient or disease-modifying medications for AD. It is necessary to advance AD research to suggest novel compounds for treatment and prevention. Prospectively, it might be reasonable to conduct clinical trials with unclean medicines that have a range of effects, including anti-amyloid and anti-tau, neurotransmitter modulation, anti-neuroinflammatory, neuroprotective, and cognitive enhancement.
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Affiliation(s)
- Musa O. Iliyasu
- Department of Anatomy, Kogi State University, Anyigba, Nigeria
- *Correspondence: Musa O. Iliyasu, ;
| | - Sunday A. Musa
- Department of Human Anatomy, Ahmadu Bello University, Zaria, Nigeria
| | - Sunday B. Oladele
- Department of Veterinary Pathology, Ahmadu Bello University, Zaria, Nigeria
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6
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Vercouillie J, Buron F, Sérrière S, Rodrigues N, Gulhan Z, Chartier A, Chicheri G, Marzag H, Oury A, Percina N, Bodard S, Ben Othman R, Busson J, Suzenet F, Guilloteau D, Marchivie M, Emond P, Routier S, Chalon S. Development and preclinical evaluation of [18F]FBVM as a new potent PET tracer for vesicular acetylcholine transporter. Eur J Med Chem 2022; 244:114794. [DOI: 10.1016/j.ejmech.2022.114794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 09/13/2022] [Accepted: 09/23/2022] [Indexed: 11/30/2022]
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7
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Tiepolt S, Meyer PM, Patt M, Deuther-Conrad W, Hesse S, Barthel H, Sabri O. PET Imaging of Cholinergic Neurotransmission in Neurodegenerative Disorders. J Nucl Med 2022; 63:33S-44S. [PMID: 35649648 DOI: 10.2967/jnumed.121.263198] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 05/06/2022] [Indexed: 12/13/2022] Open
Abstract
As a neuromodulator, the neurotransmitter acetylcholine plays an important role in cognitive, mood, locomotor, sleep/wake, and olfactory functions. In the pathophysiology of most neurodegenerative diseases, such as Alzheimer disease (AD) or Lewy body disorder (LBD), cholinergic receptors, transporters, or enzymes are involved and relevant as imaging targets. The aim of this review is to summarize current knowledge on PET imaging of cholinergic neurotransmission in neurodegenerative diseases. For PET imaging of presynaptic vesicular acetylcholine transporters (VAChT), (-)-18F-fluoroethoxybenzovesamicol (18F-FEOBV) was the first PET ligand that could be successfully translated to clinical application. Since then, the number of 18F-FEOBV PET investigations on patients with AD or LBD has grown rapidly and provided novel, important findings concerning the pathophysiology of AD and LBD. Regarding the α4β2 nicotinic acetylcholine receptors (nAChRs), various second-generation PET ligands, such as 18F-nifene, 18F-AZAN, 18F-XTRA, (-)-18F-flubatine, and (+)-18F-flubatine, were developed and successfully translated to human application. In neurodegenerative diseases such as AD and LBD, PET imaging of α4β2 nAChRs is of special value for monitoring disease progression and drugs directed to α4β2 nAChRs. For PET of α7 nAChR, 18F-ASEM and 11C-MeQAA were successfully applied in mild cognitive impairment and AD, respectively. The highest potential for α7 nAChR PET is seen in staging, in evaluating disease progression, and in therapy monitoring. PET of selective muscarinic acetylcholine receptors (mAChRs) is still in an early stage, as the development of subtype-selective radioligands is complicated. Promising radioligands to image mAChR subtypes M1 (11C-LSN3172176), M2 (18F-FP-TZTP), and M4 (11C-MK-6884) were developed and successfully translated to humans. PET imaging of mAChRs is relevant for the assessment and monitoring of therapies in AD and LBD. PET of acetylcholine esterase activity has been investigated since the 1990s. Many PET studies with 11C-PMP and 11C-MP4A demonstrated cortical cholinergic dysfunction in dementia associated with AD and LBD. Recent studies indicated a solid relationship between subcortical and cortical cholinergic dysfunction and noncognitive dysfunctions such as balance and gait in LBD. Taken together, PET of distinct components of cholinergic neurotransmission is of great interest for diagnosis, disease monitoring, and therapy monitoring and to gain insight into the pathophysiology of different neurodegenerative disorders.
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Affiliation(s)
- Solveig Tiepolt
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany; and
| | - Philipp M Meyer
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany; and
| | - Marianne Patt
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany; and
| | | | - Swen Hesse
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany; and
| | - Henryk Barthel
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany; and
| | - Osama Sabri
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany; and
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8
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Xia Y, Eeles E, Fripp J, Pinsker D, Thomas P, Latter M, Doré V, Fazlollahi A, Bourgeat P, Villemagne VL, Coulson EJ, Rose S. Reduced cortical cholinergic innervation measured using [ 18F]-FEOBV PET imaging correlates with cognitive decline in mild cognitive impairment. Neuroimage Clin 2022; 34:102992. [PMID: 35344804 PMCID: PMC8958543 DOI: 10.1016/j.nicl.2022.102992] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 03/06/2022] [Accepted: 03/22/2022] [Indexed: 12/12/2022]
Abstract
Topographic FEOBV binding correlates with domain-specific cognitive performance. Global and regional reductions in cholinergic innervation are observed in MCI. Global FEOBV SUVR is associated with basal forebrain and hippocampal volumes. Our results provide proof of concept for FEOBV PET to assess cholinergic terminal integrity.
Dysfunction of the cholinergic basal forebrain (BF) neurotransmitter system, including cholinergic axon denervation of the cortex, plays an important role in cognitive decline and dementia. A validated method to directly quantify cortical cholinergic terminal integrity enables exploration of the involvement of this system in diverse cognitive profiles associated with dementia, particularly at a prodromal stage. In this study, we used the radiotracer [18F]-fluoroethoxybenzovesamicol (FEOBV) as a direct measure of cholinergic terminal integrity and investigated its value for the assessment of cholinergic denervation in the cortex and associated cognitive deficits. Eighteen participants (8 with mild cognitive impairment (MCI) and 10 cognitively unimpaired controls) underwent neuropsychological assessment and brain imaging using FEOBV and [18F]-florbetaben for amyloid-β imaging. The MCI group showed a significant global reduction of FEOBV retention in the cortex and in the parietal and occipital cortices specifically compared to the control group. The global cortical FEOBV retention of all participants positively correlated with the BF, hippocampus and grey matter volumes, but no association was found between the global FEOBV retention and amyloid-β status. Topographic profiles from voxel-wise analysis of FEOBV images revealed significant positive correlations with the cognitive domains associated with the underlying cortical areas. Overlapping profiles of decreased FEOBV were identified in correlation with impairment in executive function, attention and language, which covered the anterior cingulate gyrus, olfactory cortex, calcarine cortex, middle temporal gyrus and caudate nucleus. However, the absence of cortical atrophy in these areas suggested that reduced cholinergic terminal integrity in the cortex is an important factor underlying the observed cognitive decline in early dementia. Our results provide support for the utility and validity of FEOBV PET for quantitative assessment of region-specific cholinergic terminal integrity that could potentially be used for early detection of cholinergic dysfunction in dementia following further validation in larger cohorts.
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Affiliation(s)
- Ying Xia
- The Australian e-Health Research Centre, CSIRO Health and Biosecurity, Brisbane, QLD, Australia.
| | - Eamonn Eeles
- Internal Medicine Service, The Prince Charles Hospital, Brisbane, QLD, Australia; School of Medicine, Northside Clinical School, The Prince Charles Hospital, Brisbane, QLD, Australia; Dementia & Neuro Mental Health Research Unit, UQCCR, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia
| | - Jurgen Fripp
- The Australian e-Health Research Centre, CSIRO Health and Biosecurity, Brisbane, QLD, Australia
| | - Donna Pinsker
- Internal Medicine Service, The Prince Charles Hospital, Brisbane, QLD, Australia; School of Psychology, The University of Queensland, Brisbane, QLD, Australia
| | - Paul Thomas
- Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia
| | - Melissa Latter
- Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia
| | - Vincent Doré
- The Australian e-Health Research Centre, CSIRO Health and Biosecurity, Brisbane, QLD, Australia; Austin Health, Melbourne, VIC, Australia
| | - Amir Fazlollahi
- The Australian e-Health Research Centre, CSIRO Health and Biosecurity, Brisbane, QLD, Australia; Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Pierrick Bourgeat
- The Australian e-Health Research Centre, CSIRO Health and Biosecurity, Brisbane, QLD, Australia
| | - Victor L Villemagne
- Austin Health, Melbourne, VIC, Australia; Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Elizabeth J Coulson
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia; School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Stephen Rose
- The Australian e-Health Research Centre, CSIRO Health and Biosecurity, Brisbane, QLD, Australia
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9
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Kim MJ, Kang JY, Kim JM, Moon JH, Lee HL, Jeong HR, Go MJ, Lee U, Heo HJ. Effect of Ethyl Acetate Fraction from Eucommia ulmoides Leaves on PM 2.5-Induced Inflammation and Cognitive Dysfunction. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:7157444. [PMID: 35607702 PMCID: PMC9124148 DOI: 10.1155/2022/7157444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/31/2022] [Accepted: 04/19/2022] [Indexed: 11/18/2022]
Abstract
This study aimed to evaluate the protective effect of the ethyl acetate from Eucommia ulmoides leaves (EFEL) on PM2.5-induced cognitive impairment in BALB/c mice. EFEL improved PM2.5-induced cognitive decline by improving spontaneous alternative behavioral and long-term memory ability. EFEL increased ferric reducing activity power (FRAP) in serum. In addition, EFEL increased superoxide dismutase (SOD) and reduced glutathione (GSH) contents and inhibited the production of malondialdehyde (MDA) in lung and brain tissues. EFEL also restored the mitochondrial function by regulating reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP) level, and ATP level in lung and brain tissues. EFEL ameliorated the cholinergic system by regulating the acetylcholine (ACh) content and acetylcholinesterase (AChE) activity in the brain tissue and the expression of AChE and choline acetyltransferase (ChAT) in the whole brain and hippocampal tissues. EFEL reduced PM2.5-induced excessive expression of inflammatory protein related to the lung, whole brain, olfactory bulb, and hippocampus. Physiological compounds of EFEL were identified as 5-O-caffeolyquinic acid, rutin, quercetin, and quercetin glycosides. As a result, EFEL has anti-inflammation and anti-amnesic effect on PM2.5-induced cognitive impairment by regulating the inflammation and inhibiting the lung and brain tissue dysfunction, and its effect is considered to be due to the physiological compounds of EFEL.
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Affiliation(s)
- Min Ji Kim
- Division of Applied Life Science (BK21), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Jin Yong Kang
- Division of Applied Life Science (BK21), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea
- World Institute of Kimchi an Annex of Korea Food Research Institute, Gwangju, Republic of Korea
| | - Jong Min Kim
- Division of Applied Life Science (BK21), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Jong Hyun Moon
- Division of Applied Life Science (BK21), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Hyo Lim Lee
- Division of Applied Life Science (BK21), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Hye Rin Jeong
- Division of Applied Life Science (BK21), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Min Ji Go
- Division of Applied Life Science (BK21), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Uk Lee
- Division of Special Forest Products, National Institute of Forest Science, Suwon 16631, Republic of Korea
| | - Ho Jin Heo
- Division of Applied Life Science (BK21), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea
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Dantas L, Forte A, Lima B, Sousa C, Vasconcelos E, Lessa P, Vieira R, Patrocínio M, Vasconcelos S. Treatment of bladder dysfunction with solifenacin: is there a risk of dementia or cognitive impairment? Braz J Med Biol Res 2022; 55:e11721. [PMID: 35320336 PMCID: PMC8851948 DOI: 10.1590/1414-431x2021e11721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 11/16/2021] [Indexed: 11/22/2022] Open
Affiliation(s)
- L.P. Dantas
- Universidade Federal do Ceará, Brasil; Hospital Geral de Fortaleza, Brasil
| | | | - B.C. Lima
- Universidade Federal do Ceará, Brasil
| | | | | | | | | | - M.C.A. Patrocínio
- Centro Universitário Christus, Brasil; Instituto Dr. Jose Frota, Brasil
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11
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Karimani A, Ramezani N, Afkhami Goli A, Nazem Shirazi MH, Nourani H, Jafari AM. Subchronic neurotoxicity of diazinon in albino mice: Impact of oxidative stress, AChE activity, and gene expression disturbances in the cerebral cortex and hippocampus on mood, spatial learning, and memory function. Toxicol Rep 2021; 8:1280-1288. [PMID: 34277358 PMCID: PMC8261896 DOI: 10.1016/j.toxrep.2021.06.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 06/06/2021] [Accepted: 06/14/2021] [Indexed: 02/03/2023] Open
Abstract
Diazinon (DZN) with prominent neurotoxic effects perturbs CNS function via multiple mechanisms. This investigation intends to explore mood, spatial learning, and memory dysfunction, acetylcholine esterase (AChE) activity, and neurodegeneration-related gene expression in the cortex and hippocampus regions of mice exposed to DZN for 63 consecutive days (subchronic exposure). Adult male albino mice were orally given sublethal DZN (DZNL = 0.1 mg/kg, DZNM = 1 mg/kg and DZNH = 10 mg/kg). All mice in the DZNH group died within 3 weeks postexposure. DZNL and DZNM caused body and brain weight loss (p < 0.05). Completing 9 weeks of DZN exposure, a marked decline in AChE activity and oxidative stress level was indicated in both brain regions (p < 0.05). Also, synaptophysin, vesicular acetylcholine transferase, and glutamate decarboxylase gene expressions were affected in both brain regions (p < 0.05). Furthermore, the present study revealed that DZN administration increased anxiety and depressive-like behaviors (p < 0.0001). Spatial learning and short- and long-memory were severely affected by DZNL and DZNM treatments (p < 0.0001). Taken together, subchronic exposure to low and medium doses of DZN can cause AChE inhibition, oxidative damage, and neurotransmitter disturbances in brain cells and induce neurodegeneration. These changes would impair mood, spatial learning, and memory function.
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Key Words
- AChE, acetylcholine esterase
- AD, Alzheimer’s disease
- Ach, acetylcholine
- COX-2, cyclooxygenase-2
- CX, cerebral cortex
- Cerebral cortex
- DZN, diazinon
- DZO, diazoxon
- Diazinon
- FRAP, ferric reducing antioxidant power
- FST, forced swim test
- GABA, ϒ-aminobutyric acid
- GAD65, glutamate decarboxylase 65
- HP, hippocampus
- Hippocampus
- LD50, lethal dose 50
- MB, marble burying test
- MDA, malondialdehyde
- MWM, Morris water maze test
- Memory
- NOAEL, no-observed-adverse-effect level
- Neurodegenerative diseases
- Ops, organophosphates
- PD, Parkinson’s disease
- RNS, reactive nitrogen species
- ROS, reactive oxygen species
- SEM, standard error of the mean
- SYP, synaptophysin
- Spatial learning
- VAChT, vesicular acetylcholine transferase
- qRT-PCR, quantitative reverse transcription-polymerase chain reaction
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Affiliation(s)
- Asieh Karimani
- Department of Toxicology, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Nasrin Ramezani
- Department of Toxicology, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Amir Afkhami Goli
- Department of Toxicology, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
| | | | - Hosein Nourani
- Department of Pathology, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Amir Moghaddam Jafari
- Department of Toxicology, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
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12
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Erukainure OL, Salau VF, Bharuth V, Koorbanally NA, Islam MS. Hyperglycemia alters lipid metabolism and ultrastructural morphology of cerebellum in brains of diabetic rats: Therapeutic potential of raffia palm (Raphia hookeri G. Mann & H. Wendl) wine. Neurochem Int 2020; 140:104849. [PMID: 32927025 DOI: 10.1016/j.neuint.2020.104849] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 09/07/2020] [Accepted: 09/08/2020] [Indexed: 12/17/2022]
Abstract
The present study investigated the effect of raffia palm (Raphia hookeri) wine (RPW) on hyperglycemia-mediated lipid metabolites and pathways, functional chemistry and ultrastructural morphology of cerebellums in type 2 diabetes (T2D). T2D was induced in male Sprague-Dawley rats by feeding with 10% fructose ad libitum for 2 weeks before injecting intraperitoneally with 40 mg/kg bodyweight (bw) streptozotocin. Following confirmation of hyperglycemia at blood glucose >200 mg/dL, diabetic rats were treated with RPW at 150 and 300 mg/kg bw respectively. Metformin served as the standard drug. Negative and normal controls consisted of untreated diabetic and non-diabetic rats, respectively. After 5 weeks of treatment, the rats were humanely sacrificed, and their cerebellum excised from the harvested brains. GC-MS analysis revealed significant alterations in cerebellar lipid metabolites depicted by changes in unsaturated and saturated fatty acids, fatty - esters, alcohols, and amides, glycols and steroids on induction of T2D. Pathway enrichment analysis of the lipid metabolites revealed inactivation of arachidonic metabolic pathway following T2D induction. Treatment with both doses of RPW restored most of the metabolites, while reactivating arachidonic acid metabolism (high dose only). Low dose of RPW led to the activation of retinol metabolism. Both doses of RPW maintained cerebellar functional chemistry as revealed by FTIR analysis. TEM analysis revealed swollen mitochondria, depleted numbers of synaptic vesicles, and shrunk synaptic clefts following induction of T2D. These ultrastructural morphologies were improved in RPW-treated rats. These results portray the therapeutic potential of raffia palm wine in the management of neurodegenerative complications in T2D.
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Affiliation(s)
- Ochuko L Erukainure
- Department of Biochemistry, University of KwaZulu-Natal, Westville Campus, Durban, 4000, South Africa; Department of Pharmacology, University of the Free State, Bloemfontein, 9300, South Africa
| | - Veronica F Salau
- Department of Biochemistry, University of KwaZulu-Natal, Westville Campus, Durban, 4000, South Africa
| | - Vishal Bharuth
- Microscopy and Microanalysis Unit, University of KwaZulu-Natal, Westville Campus, Durban, 4000, South Africa
| | - Neil A Koorbanally
- School of Chemistry and Physics, University of KwaZulu-Natal, Westville Campus, Durban, 4000, South Africa
| | - Md Shahidul Islam
- Department of Biochemistry, University of KwaZulu-Natal, Westville Campus, Durban, 4000, South Africa.
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13
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Cacabelos R. Pharmacogenetic considerations when prescribing cholinesterase inhibitors for the treatment of Alzheimer's disease. Expert Opin Drug Metab Toxicol 2020; 16:673-701. [PMID: 32520597 DOI: 10.1080/17425255.2020.1779700] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
INTRODUCTION Cholinergic dysfunction, demonstrated in the late 1970s and early 1980s, led to the introduction of acetylcholinesterase inhibitors (AChEIs) in 1993 (Tacrine) to enhance cholinergic neurotransmission as the first line of treatment against Alzheimer's disease (AD). The new generation of AChEIs, represented by Donepezil (1996), Galantamine (2001) and Rivastigmine (2002), is the only treatment for AD to date, together with Memantine (2003). AChEIs are not devoid of side-effects and their cost-effectiveness is limited. An option to optimize the correct use of AChEIs is the implementation of pharmacogenetics (PGx) in the clinical practice. AREAS COVERED (i) The cholinergic system in AD, (ii) principles of AD PGx, (iii) PGx of Donepezil, Galantamine, Rivastigmine, Huperzine and other treatments, and (iv) practical recommendations. EXPERT OPINION The most relevant genes influencing AChEI efficacy and safety are APOE and CYPs. APOE-4 carriers are the worst responders to AChEIs. With the exception of Rivastigmine (UGT2B7, BCHE-K), the other AChEIs are primarily metabolized via CYP2D6, CYP3A4, and UGT enzymes, with involvement of ABC transporters and cholinergic genes (CHAT, ACHE, BCHE, SLC5A7, SLC18A3, CHRNA7) in most ethnic groups. Defective variants may affect the clinical response to AChEIs. PGx geno-phenotyping is highly recommended prior to treatment.
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Affiliation(s)
- Ramón Cacabelos
- Department of Genomic Medicine, EuroEspes Biomedical Research Center, International Center of Neuroscience and Genomic Medicine , Bergondo, Corunna, Spain
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14
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Isaev NK, Stelmashook EV, Genrikhs EE. Neurogenesis and brain aging. Rev Neurosci 2020; 30:573-580. [PMID: 30763272 DOI: 10.1515/revneuro-2018-0084] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 11/18/2018] [Indexed: 12/13/2022]
Abstract
Human aging affects the entire organism, but aging of the brain must undoubtedly be different from that of all other organs, as neurons are highly differentiated postmitotic cells, for the majority of which the lifespan in the postnatal period is equal to the lifespan of the entire organism. In this work, we examine the distinctive features of brain aging and neurogenesis during normal aging, pathological aging (Alzheimer's disease), and accelerated aging (Hutchinson-Gilford progeria syndrome and Werner syndrome).
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Affiliation(s)
- Nickolay K Isaev
- M.V. Lomonosov Moscow State University, N.A. Belozersky Institute of Physico-Chemical Biology, Biological Faculty, Moscow 119991, Russia.,Research Center of Neurology, Moscow 125367, Russia
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15
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Cisneros-Franco JM, Voss P, Kang MS, Thomas ME, Côté J, Ross K, Gaudreau P, Rudko DA, Rosa-Neto P, de-Villers-Sidani É. PET Imaging of Perceptual Learning-Induced Changes in the Aged Rodent Cholinergic System. Front Neurosci 2020; 13:1438. [PMID: 32038142 PMCID: PMC6985428 DOI: 10.3389/fnins.2019.01438] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 12/20/2019] [Indexed: 12/14/2022] Open
Abstract
The cholinergic system enhances attention and gates plasticity, making it a major regulator of adult learning. With aging, however, progressive degeneration of the cholinergic system impairs both the acquisition of new skills and functional recovery following neurological injury. Although cognitive training and perceptual learning have been shown to enhance auditory cortical processing, their specific impact on the cholinergic system remains unknown. Here we used [18F]FEOBV, a positron emission tomography (PET) radioligand that selectively binds to the vesicular acetylcholine transporter (VAChT), as a proxy to assess whether training on a perceptual task results in increased cholinergic neurotransmission. We show for the first time that perceptual learning is associated with region-specific changes in cholinergic neurotransmission, as detected by [18F]FEOBV PET imaging and corroborated with immunohistochemistry.
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Affiliation(s)
- J Miguel Cisneros-Franco
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada.,Centre for Research on Brain, Language and Music, McGill University, Montreal, QC, Canada
| | - Patrice Voss
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada.,Centre for Research on Brain, Language and Music, McGill University, Montreal, QC, Canada
| | - Min Su Kang
- Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada.,Research Centre for Studies in Aging, McGill University, Montreal, QC, Canada
| | - Maryse E Thomas
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada.,Centre for Research on Brain, Language and Music, McGill University, Montreal, QC, Canada
| | - Jonathan Côté
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada.,Centre for Research on Brain, Language and Music, McGill University, Montreal, QC, Canada
| | - Karen Ross
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Pierrette Gaudreau
- Réseau Québécois de Recherche sur le Vieillissement, Université de Montréal, Montreal, QC, Canada
| | - David A Rudko
- Department of Biomedical Engineering, McGill University, Montreal, QC, Canada
| | - Pedro Rosa-Neto
- Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada.,Research Centre for Studies in Aging, McGill University, Montreal, QC, Canada
| | - Étienne de-Villers-Sidani
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada.,Centre for Research on Brain, Language and Music, McGill University, Montreal, QC, Canada
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16
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Qin Q, Li Y. Herpesviral infections and antimicrobial protection for Alzheimer's disease: Implications for prevention and treatment. J Med Virol 2019; 91:1368-1377. [PMID: 30997676 DOI: 10.1002/jmv.25481] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 04/04/2019] [Indexed: 02/05/2023]
Abstract
Accumulating evidence suggests that infections by herpesviruses might be closely linked to Alzheimer's disease (AD). Pathological hallmarks of AD brains include senile plaques induced by amyloid β peptide (Aβ) in the extracellular space and intracellular neurofibrillary tangles (NFTs) consisting of phosphorylated tau protein. The prevailing hypothesis for the mechanism of AD is amyloid cascade reaction. Recent studies revealed that infections by herpesviruses induce the similar pathological hallmarks of AD, including Aβ production, phosphorylation of tau (P-tau), oxidative stress, neuroinflammation, etc. Aβ peptide is regarded as one of the antimicrobial peptides, which inhibits HSV-1 replication. In the elderly, reactivation of herpesviruses might act as an initiator for amyloid cascade reaction in vulnerable individuals, triggering the neurofibrillary formation of phosphorylated tau and inducing oxidative stress and neuroinflammation, which can further contribute to the accumulation of Aβ and P-tau by impairing mitochondria and autophagosome. Epidemiological studies have shown AD susceptibility genes, such as APOE-ε4 allele, are highly linked to infections by herpesviruses. Interestingly, anti-herpesviral therapy significantly reduced the risk of AD in a large population study. Given that herpesviruses are arguably the most prevalent opportunistic pathogens and often reactivate in the elderly, it is reasonable to argue reactivation of herpesviruses might be major culprits for initiating AD in individuals carrying AD susceptibility genes. In this review, we summarize epidemiological and molecular evidence that support for a hypothesis of herpesviral infections and antimicrobial protection in the development of AD, and discuss the implications for future prevention and treatment of the disease.
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Affiliation(s)
- Qingsong Qin
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, China
| | - Yun Li
- Sleep Medicine Center, Shantou University Medical College, Shantou, Guangdong, China
- Mental Health Center, Shantou University Medical College, Shantou, Guangdong, China
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17
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Gauthier S, Ng KP, Pascoal TA, Zhang H, Rosa-Neto P. Targeting Alzheimer's Disease at the Right Time and the Right Place: Validation of a Personalized Approach to Diagnosis and Treatment. J Alzheimers Dis 2019; 64:S23-S31. [PMID: 29504543 PMCID: PMC6004905 DOI: 10.3233/jad-179924] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Cautious optimism is appropriate for a near future (five years) time frame for a number of drugs acting on the different pathophysiological components of Alzheimer’s disease (amyloid deposition, tau hyperphosphorylation, neuroinflammation, vascular changes, to name the most important known so far). Since the relative weight of these components will be different between individuals and will even change over time for each individual, a ‘one drug fit for all’ approach is no longer defensible. Precision medicine using biomarkers in the diagnosis and treatment of Alzheimer’s disease is the new strategy.
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Affiliation(s)
- Serge Gauthier
- McGill Center for Studies in Aging, Douglas Mental Health Research Institute, Montreal, Canada
| | - Kok Pin Ng
- Department of Neurology, National Neuroscience Institute, Singapore
| | - Tharick A Pascoal
- McGill Center for Studies in Aging, Douglas Mental Health Research Institute, Montreal, Canada
| | - Hua Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Pedro Rosa-Neto
- McGill Center for Studies in Aging, Douglas Mental Health Research Institute, Montreal, Canada
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18
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Yue X, Luo Z, Liu H, Kaneshige K, Parsons SM, Perlmutter JS, Tu Z. Radiosynthesis and evaluation of a fluorine-18 labeled radioligand targeting vesicular acetylcholine transporter. Bioorg Med Chem Lett 2018; 28:3425-3430. [PMID: 30274694 DOI: 10.1016/j.bmcl.2018.09.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 09/21/2018] [Accepted: 09/22/2018] [Indexed: 12/28/2022]
Abstract
Vesicular acetylcholine transporter (VAChT) is a reliable biomarker for assessing the loss of cholinergic neurons in the brain that is associated with cognitive impairment of patients. 5-Hydrotetralin compound (±)-5-OH-VAT is potent (Ki = 4.64 ± 0.32 nM) and selective for VAChT (>1800-fold and 398-fold for σ1 and σ2 receptor, respectively) with favorable hydrophilicity (LogD = 1.78), while (-)-5-OH-VAT originally serves as the radiolabeling precursor of (-)-[18F]VAT, a promising VAChT radiotracer with a logD value of 2.56. To evaluate (-)-5-OH-[18F]VAT as a radiotracer for VAChT, we performed in vitro binding assay to determine the potency of the minus enantiomer (-)-5-OH-VAT and plus enantiomer (+)-5-OH-VAT, indicating that (-)-5-OH-VAT is a more potent VAChT enantiomer. Radiosynthesis of (-)-5-OH-[18F]VAT was explored using three strategies. (-)-5-OH-[18F]VAT was achieved with a good yield (24 ± 6%) and high molar activity (∼37 GBq/µmol, at the end of synthesis) using a microwave assisted two-step one-pot procedure that started with di-MOM protected nitro-containing precursor (-)-6. MicroPET studies in the brain of nonhuman primate (NHP) suggest that (-)-5-OH-[18F]VAT readily penetrated the blood brain barrier and specifically accumulated in the VAChT-enriched striatum with improved washout kinetics from striatum compared to [18F]VAT. Nevertheless, the lower target to non-target ratio may limit its use for in vivo measurement of the VAChT level in the brain.
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Affiliation(s)
- Xuyi Yue
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, United States
| | - Zonghua Luo
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, United States
| | - Hui Liu
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, United States
| | - Kota Kaneshige
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, United States
| | - Stanley M Parsons
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, United States
| | - Joel S Perlmutter
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, United States; Department of Neurology, Washington University School of Medicine, St Louis, MO 63110, United States
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, United States.
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19
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Pascoal TA, Shin M, Kang MS, Chamoun M, Chartrand D, Mathotaarachchi S, Bennacef I, Therriault J, Ng KP, Hopewell R, Bouhachi R, Hsiao HH, Benedet AL, Soucy JP, Massarweh G, Gauthier S, Rosa-Neto P. In vivo quantification of neurofibrillary tangles with [ 18F]MK-6240. ALZHEIMERS RESEARCH & THERAPY 2018; 10:74. [PMID: 30064520 PMCID: PMC6069775 DOI: 10.1186/s13195-018-0402-y] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/06/2018] [Indexed: 01/02/2023]
Abstract
BACKGROUND Imaging agents capable of quantifying the brain's tau aggregates will allow a more precise staging of Alzheimer's disease (AD). The aim of the present study was to examine the in vitro properties as well as the in vivo kinetics, using gold standard methods, of the novel positron emission tomography (PET) tau imaging agent [18F]MK-6240. METHODS In vitro properties of [18F]MK-6240 were estimated with autoradiography in postmortem brain tissues of 14 subjects (seven AD patients and seven age-matched controls). In vivo quantification of [18F]MK-6240 binding was performed in 16 subjects (four AD patients, three mild cognitive impairment patients, six healthy elderly individuals, and three healthy young individuals) who underwent 180-min dynamic scans; six subjects had arterial sampling for metabolite correction. Simplified approaches for [18F]MK-6240 quantification were validated using full kinetic modeling with metabolite-corrected arterial input function. All participants also underwent amyloid-PET and structural magnetic resonance imaging. RESULTS In vitro [18F]MK-6240 uptake was higher in AD patients than in age-matched controls in brain regions expected to contain tangles such as the hippocampus, whereas no difference was found in the cerebellar gray matter. In vivo, [18F]MK-6240 displayed favorable kinetics with rapid brain delivery and washout. The cerebellar gray matter had low binding across individuals, showing potential for use as a reference region. A reversible two-tissue compartment model well described the time-activity curves across individuals and brain regions. Distribution volume ratios using the plasma input and standardized uptake value ratios (SUVRs) calculated after the binding approached equilibrium (90 min) were correlated and higher in mild cognitive impairment or AD dementia patients than in controls. Reliability analysis revealed robust SUVRs calculated from 90 to 110 min, while earlier time points provided inaccurate estimates. CONCLUSIONS This evaluation shows an [18F]MK-6240 distribution in concordance with postmortem studies and that simplified quantitative approaches such as the SUVR offer valid estimates of neurofibrillary tangle load 90 min post injection. [18F]MK-6240 is a promising tau tracer with the potential to be applied in the disease diagnosis and assessment of therapeutic interventions.
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Affiliation(s)
- Tharick A Pascoal
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, QC, H4H 1R3, Canada.,Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Monica Shin
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, QC, H4H 1R3, Canada
| | - Min Su Kang
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, QC, H4H 1R3, Canada.,Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Mira Chamoun
- Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Daniel Chartrand
- Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Sulantha Mathotaarachchi
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, QC, H4H 1R3, Canada.,Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Idriss Bennacef
- Translational Biomarkers, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA, 19486, USA
| | - Joseph Therriault
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, QC, H4H 1R3, Canada
| | - Kok Pin Ng
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, QC, H4H 1R3, Canada
| | - Robert Hopewell
- Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Reda Bouhachi
- Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Hung-Hsin Hsiao
- Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Andrea L Benedet
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, QC, H4H 1R3, Canada
| | - Jean-Paul Soucy
- Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Gassan Massarweh
- Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Serge Gauthier
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, QC, H4H 1R3, Canada
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, QC, H4H 1R3, Canada. .,Montreal Neurological Institute, 3801 University Street, Montreal, QC, H3A 2B4, Canada. .,Douglas Hospital, McGill University, 6875 La Salle Blvd-FBC room 3149, Montreal, QC, H4H 1R3, Canada.
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20
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Alasmari F, Ashby CR, Hall FS, Sari Y, Tiwari AK. Modulation of the ATP-Binding Cassette B1 Transporter by Neuro-Inflammatory Cytokines: Role in the Pathogenesis of Alzheimer's Disease. Front Pharmacol 2018; 9:658. [PMID: 29973883 PMCID: PMC6020013 DOI: 10.3389/fphar.2018.00658] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 06/01/2018] [Indexed: 12/13/2022] Open
Affiliation(s)
- Fawaz Alasmari
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.,Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, United States
| | - Charles R Ashby
- Pharmaceutical Sciences, College of Pharmacy, St. John's University Queens, New York, NY, United States
| | - Frank S Hall
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Youssef Sari
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Amit K Tiwari
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
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21
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Al-Onaizi MA, Parfitt GM, Kolisnyk B, Law CSH, Guzman MS, Barros DM, Leung LS, Prado MAM, Prado VF. Regulation of Cognitive Processing by Hippocampal Cholinergic Tone. Cereb Cortex 2018; 27:1615-1628. [PMID: 26803167 DOI: 10.1093/cercor/bhv349] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cholinergic dysfunction has been associated with cognitive abnormalities in a variety of neurodegenerative and neuropsychiatric diseases. Here we tested how information processing is regulated by cholinergic tone in genetically modified mice targeting the vesicular acetylcholine transporter (VAChT), a protein required for acetylcholine release. We measured long-term potentiation of Schaffer collateral-CA1 synapses in vivo and assessed information processing by using a mouse touchscreen version of paired associates learning task (PAL). Acquisition of information in the mouse PAL task correlated to levels of hippocampal VAChT, suggesting a critical role for cholinergic tone. Accordingly, synaptic plasticity in the hippocampus in vivo was disturbed, but not completely abolished, by decreased hippocampal cholinergic signaling. Disrupted forebrain cholinergic signaling also affected working memory, a result reproduced by selectively decreasing VAChT in the hippocampus. In contrast, spatial memory was relatively preserved, whereas reversal spatial memory was sensitive to decreased hippocampal cholinergic signaling. This work provides a refined roadmap of how synaptically secreted acetylcholine influences distinct behaviors and suggests that distinct forms of cognitive processing may be regulated in different ways by cholinergic activity.
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Affiliation(s)
| | - Gustavo M Parfitt
- Robarts Research Institute.,Programa de Pós-graduação em Ciências Fisiológicas, Fisiologia Animal Comparada, Laboratório de Neurociências (FURG), Brazil
| | | | - Clayton S H Law
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, CanadaN6A5K8
| | - Monica S Guzman
- Robarts Research Institute.,Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada N6A5K8
| | - Daniela Martí Barros
- Programa de Pós-graduação em Ciências Fisiológicas, Fisiologia Animal Comparada, Laboratório de Neurociências (FURG), Brazil
| | - L Stan Leung
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, CanadaN6A5K8
| | - Marco A M Prado
- Robarts Research Institute.,Department of Anatomy and Cell Biology.,Graduate Program in Neuroscience and.,Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada N6A5K8
| | - Vania F Prado
- Robarts Research Institute.,Department of Anatomy and Cell Biology.,Graduate Program in Neuroscience and.,Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada N6A5K8
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22
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Aghourian M, Legault-Denis C, Soucy JP, Rosa-Neto P, Gauthier S, Kostikov A, Gravel P, Bédard MA. Quantification of brain cholinergic denervation in Alzheimer's disease using PET imaging with [ 18F]-FEOBV. Mol Psychiatry 2017; 22:1531-1538. [PMID: 28894304 DOI: 10.1038/mp.2017.183] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 07/17/2017] [Accepted: 07/20/2017] [Indexed: 01/08/2023]
Abstract
18F-fluoroethoxybenzovesamicol (FEOBV) is a new PET radiotracer that binds to the vesicular acetylcholine transporter. In both animals and healthy humans, FEOBV was found sensitive and reliable to characterize presynaptic cholinergic nerve terminals in the brain. It has been used here for we believe the first time in patients with Alzheimer's disease (AD) to quantify brain cholinergic losses. The sample included 12 participants evenly divided in healthy subjects and patients with AD, all assessed with the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) cognitive scales. Every participant underwent three consecutive PET imaging sessions with (1) the FEOBV as a tracer of the cholinergic terminals, (2) the 18F-NAV4694 (NAV) as an amyloid-beta tracer, and (3) the 18F-Fluorodeoxyglucose (FDG) as a brain metabolism agent. Standardized uptake value ratios (SUVRs) were computed for each tracer, and compared between the two groups using voxel wise t-tests. Correlations were also computed between each tracer and the cognitive scales, as well as between FEOBV and the two other radiotracers. Results showed major reductions of FEOBV uptake in multiple cortical areas that were evident in each AD subject, and in the AD group as a whole when compared to the control group. FDG and NAV were also able to distinguish the two groups, but with lower sensitivity than FEOBV. FEOBV uptake values were positively correlated with FDG in numerous cortical areas, and negatively correlated with NAV in some restricted areas. The MMSE and MoCA cognitive scales were found to correlate significantly with FEOBV and with FDG, but not with NAV. We concluded that PET imaging with FEOBV is more sensitive than either FDG or NAV to distinguish AD patients from control subjects, and may be useful to quantify disease severity. FEOBV can be used to assess cholinergic degeneration in human, and may represent an excellent biomarker for AD.
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Affiliation(s)
- M Aghourian
- Université du Québec à Montréal (UQAM), Cognitive Pharmacology Research Unit, Montreal, QC, Canada.,McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada.,McGill Centre for Studies in Aging, Douglas Mental Health University Institute, Verdun, QC, Canada
| | - C Legault-Denis
- Université du Québec à Montréal (UQAM), Cognitive Pharmacology Research Unit, Montreal, QC, Canada.,McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada.,McGill Centre for Studies in Aging, Douglas Mental Health University Institute, Verdun, QC, Canada
| | - J-P Soucy
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada.,Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.,PERFORM Centre, Concordia University, Montreal, QC, Canada
| | - P Rosa-Neto
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada.,McGill Centre for Studies in Aging, Douglas Mental Health University Institute, Verdun, QC, Canada.,Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
| | - S Gauthier
- McGill Centre for Studies in Aging, Douglas Mental Health University Institute, Verdun, QC, Canada.,Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
| | - A Kostikov
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada.,Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
| | - P Gravel
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
| | - M-A Bédard
- Université du Québec à Montréal (UQAM), Cognitive Pharmacology Research Unit, Montreal, QC, Canada.,McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada.,McGill Centre for Studies in Aging, Douglas Mental Health University Institute, Verdun, QC, Canada
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23
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Haam J, Yakel JL. Cholinergic modulation of the hippocampal region and memory function. J Neurochem 2017; 142 Suppl 2:111-121. [PMID: 28791706 DOI: 10.1111/jnc.14052] [Citation(s) in RCA: 234] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 04/17/2017] [Accepted: 04/18/2017] [Indexed: 12/20/2022]
Abstract
Acetylcholine (ACh) plays an important role in memory function and has been implicated in aging-related dementia, in which the impairment of hippocampus-dependent learning strongly manifests. Cholinergic neurons densely innervate the hippocampus, mediating the formation of episodic as well as semantic memory. Here, we will review recent findings on acetylcholine's modulation of memory function, with a particular focus on hippocampus-dependent learning, and the circuits involved. In addition, we will discuss the complexity of ACh actions in memory function to better understand the physiological role of ACh in memory. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms.
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Affiliation(s)
- Juhee Haam
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
| | - Jerrel L Yakel
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
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24
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Ng KP, Pascoal TA, Mathotaarachchi S, Therriault J, Kang MS, Shin M, Guiot MC, Guo Q, Harada R, Comley RA, Massarweh G, Soucy JP, Okamura N, Gauthier S, Rosa-Neto P. Monoamine oxidase B inhibitor, selegiline, reduces 18F-THK5351 uptake in the human brain. ALZHEIMERS RESEARCH & THERAPY 2017; 9:25. [PMID: 28359327 PMCID: PMC5374697 DOI: 10.1186/s13195-017-0253-y] [Citation(s) in RCA: 243] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/01/2017] [Indexed: 01/19/2023]
Abstract
Background 18F-THK5351 is a quinoline-derived tau imaging agent with high affinity to paired helical filaments (PHF). However, high levels of 18F-THK5351 retention in brain regions thought to contain negligible concentrations of PHF raise questions about the interpretation of the positron emission tomography (PET) signals, particularly given previously described interactions between quinolone derivatives and monoamine oxidase B (MAO-B). Here, we tested the effects of MAO-B inhibition on 18F-THK5351 brain uptake using PET and autoradiography. Methods Eight participants (five mild cognitive impairment, two Alzheimer’s disease, and one progressive supranuclear palsy) had baseline 18F-AZD4694 and 18F-THK5351 scans in order to quantify brain amyloid and PHF load, respectively. A second 18F-THK5351 scan was conducted 1 week later, 1 h after a 10-mg oral dose of selegiline. Three out of eight patients also had a third 18F-THK5351 scan 9–28 days after the selegiline administration. The primary outcome measure was standardized uptake value (SUV), calculated using tissue radioactivity concentration from 50 to 70 min after 18F-THK5351 injection, normalizing for body weight and injected radioactivity. The SUV ratio (SUVR) was determined using the cerebellar cortex as the reference region. 18F-THK5351 competition autoradiography studies in postmortem tissue were conducted using 150 and 500 nM selegiline. Results At baseline, 18F-THK5351 SUVs were highest in the basal ganglia (0.64 ± 0.11) and thalamus (0.62 ± 0.14). In the post-selegiline scans, the regional SUVs were reduced on average by 36.7% to 51.8%, with the greatest reduction noted in the thalamus (51.8%) and basal ganglia (51.4%). MAO-B inhibition also reduced 18F-THK5351 SUVs in the cerebellar cortex (41.6%). The SUVs remained reduced in the three patients imaged at 9–28 days. Tissue autoradiography confirmed the effects of MAO-B inhibition on 18F-THK5351 uptake. Conclusions These results indicate that the interpretation of 18F-THK5351 PET images, with respect to tau, is confounded by the high MAO-B availability across the entire brain. In addition, the heterogeneous MAO-B availability across the cortex may limit the interpretation of 18F-THK5351 scans using reference region methods.
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Affiliation(s)
- Kok Pin Ng
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada.,Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore.,Alzheimer's Disease Research Unit, The McGill University Research Centre for Studies in Aging, McGill University, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Tharick A Pascoal
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Sulantha Mathotaarachchi
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Joseph Therriault
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Min Su Kang
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Monica Shin
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Marie-Christine Guiot
- Montreal Neurological Institute/Hospital, Department of Pathology, McGill University Hospital Centre, 3801 University Street, Montreal, Québec, H3A 2B4, Canada
| | - Qi Guo
- AbbVie Inc., 1 North Waukegan Road, North Chicago, IL, USA
| | - Ryuichi Harada
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | | | - Gassan Massarweh
- McConnell Brain Imaging Centre, McGill University, 3801 University Street, Montreal, Québec, H3A 2B4, Canada
| | - Jean-Paul Soucy
- McConnell Brain Imaging Centre, McGill University, 3801 University Street, Montreal, Québec, H3A 2B4, Canada
| | - Nobuyuki Okamura
- Division of Pharmacology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai, 981-8558, Japan
| | - Serge Gauthier
- Alzheimer's Disease Research Unit, The McGill University Research Centre for Studies in Aging, McGill University, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada. .,Alzheimer's Disease Research Unit, The McGill University Research Centre for Studies in Aging, McGill University, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada. .,Montreal Neurological Institute, 3801 University Street, Montreal, Québec, H3A 2B4, Canada. .,Department of Neurology and Neurosurgery, McGill University, 3801 University Street, Montreal, Québec, H3A 2B4, Canada.
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25
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Gibon J, Kang MS, Aliaga A, Sharif B, Rosa-Neto P, Séguéla P, Barker PA, Kostikov A. Towards the PET radiotracer for p75 neurotrophin receptor: [(11)C]LM11A-24 shows biological activity in vitro, but unfavorable ex vivo and in vivo profile. Bioorg Med Chem 2016; 24:4759-4765. [PMID: 27567078 DOI: 10.1016/j.bmc.2016.08.020] [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: 07/04/2016] [Revised: 08/08/2016] [Accepted: 08/12/2016] [Indexed: 12/13/2022]
Abstract
Mature neurotrophins as well as their pro forms are critically involved in the regulation of neuronal functions. They are signaling through three distinct types of receptors: tropomyosin receptor kinase family (TrkA/B/C), p75 neurotrophin receptor (p75(NTR)) and sortilin. Aberrant expression of p75(NTR) in the CNS is implicated in a variety of neurodegenerative diseases, including Alzheimer's disease. The goal of this work was to evaluate one of the very few reported p75(NTR) small molecule ligands as a lead compound for development of novel PET radiotracers for in vivo p75(NTR) imaging. Here we report that previously described ligand LM11A-24 shows significant inhibition of carbachol-induced persistent firing (PF) of entorhinal cortex (EC) pyramidal neurons in wild-type mice via selective interaction with p75(NTR). Based on this electrophysiological assay, the compound has very high potency with an EC50<10nM. We optimized the radiosynthesis of [(11)C]LM11A-24 as the first attempt to develop PET radioligand for in vivo imaging of p75(NTR). Despite some weak interaction with CNS tissues, the radiolabeled compound showed unfavorable in vivo profile presumably due to high hydrophilicity.
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Affiliation(s)
- Julien Gibon
- University of British Columbia, 3187 University Way, Kelowna, BC V1V1V7, Canada; Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC H3A2B4, Canada
| | - Min Su Kang
- Translational Neuroimaging Laboratory, McGill University Research Centre for Studies in Aging, Douglas Mental Health University Institute, 6875 Boulevard LaSalle, Montreal, QC H4H 1R3, Canada
| | - Arturo Aliaga
- Translational Neuroimaging Laboratory, McGill University Research Centre for Studies in Aging, Douglas Mental Health University Institute, 6875 Boulevard LaSalle, Montreal, QC H4H 1R3, Canada
| | - Behrang Sharif
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC H3A2B4, Canada
| | - Pedro Rosa-Neto
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC H3A2B4, Canada; Translational Neuroimaging Laboratory, McGill University Research Centre for Studies in Aging, Douglas Mental Health University Institute, 6875 Boulevard LaSalle, Montreal, QC H4H 1R3, Canada
| | - Philippe Séguéla
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC H3A2B4, Canada
| | - Philip A Barker
- University of British Columbia, 3187 University Way, Kelowna, BC V1V1V7, Canada
| | - Alexey Kostikov
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC H3A2B4, Canada.
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26
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Bielarczyk H, Jankowska-Kulawy A, Höfling C, Ronowska A, Gul-Hinc S, Roßner S, Schliebs R, Pawelczyk T, Szutowicz A. AβPP-Transgenic 2576 Mice Mimic Cell Type-Specific Aspects of Acetyl-CoA-Linked Metabolic Deficits in Alzheimer's Disease. J Alzheimers Dis 2016; 48:1083-94. [PMID: 26402099 DOI: 10.3233/jad-150327] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The pyruvate-derived acetyl-CoA is a principal direct precursor substrate for bulk energy synthesis in the brain. Deficits of pyruvate dehydrogenase in the neocortex are common features of Alzheimer's disease and other age-related encephalopathies in humans. Therefore, amyloid-β overload in brains of diverse transgenic Alzheimer's disease model animals was investigated as one of neurotoxic compounds responsible for pyruvate dehydrogenase inhibition yielding deficits of cholinergic neurotransmission and cognitive functions. Brains of aged, 14-16-month-old Tg2576 mice contained 0.6 μmol/kg levels of amyloid-β1 - 42. Activities of pyruvate dehydrogenase complex, choline acetyltransferase, and several enzymes of acetyl-CoA and energy metabolism were found to be unchanged in both forebrain mitochondria and synaptosomes of Tg2576 mice, indicating preservation of structural integrity at least in cholinergic neuronal cells. However, in transgenic brain synaptosomes, pyruvate utilization, mitochondrial levels, and cytoplasmic acetyl-CoA levels, as well as acetylcholine content and its quantal release, were all found to be decreased by 25-40% . On the contrary, activation of pyruvate utilization was detected and no alterations in acetyl-CoA content and citrate or α-ketoglutarate accumulation were observed in transgenic whole brain mitochondria. These data indicate that amyloid-β evoked deficits in acetyl-CoA are confined to mitochondrial and cytoplasmic compartments of Tg2576 nerve terminals, becoming early primary signals paving the path for further stages of neurodegeneration. On the other hand, acetyl-CoA synthesis in mitochondrial compartments of glial cells seems to be activated despite amyloid-β accumulated in transgenic brains.
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Affiliation(s)
- Hanna Bielarczyk
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | | | - Corinna Höfling
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Anna Ronowska
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Sylwia Gul-Hinc
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Steffen Roßner
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Reinhard Schliebs
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Tadeusz Pawelczyk
- Department of Molecular Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Andrzej Szutowicz
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
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27
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Eisenmenger LB, Huo EJ, Hoffman JM, Minoshima S, Matesan MC, Lewis DH, Lopresti BJ, Mathis CA, Okonkwo DO, Mountz JM. Advances in PET Imaging of Degenerative, Cerebrovascular, and Traumatic Causes of Dementia. Semin Nucl Med 2016; 46:57-87. [DOI: 10.1053/j.semnuclmed.2015.09.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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28
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Jin H, Zhang X, Yue X, Liu H, Li J, Yang H, Flores H, Su Y, Parsons SM, Perlmutter JS, Tu Z. Kinetics modeling and occupancy studies of a novel C-11 PET tracer for VAChT in nonhuman primates. Nucl Med Biol 2015; 43:131-9. [PMID: 26872437 DOI: 10.1016/j.nucmedbio.2015.11.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Revised: 10/29/2015] [Accepted: 11/05/2015] [Indexed: 01/18/2023]
Abstract
INTRODUCTION Deficits in cholinergic function have been found in the aged brain and in neurodegenerative diseases including Alzheimer's disease (AD) and Parkinson's disease (PD). The vesicular acetylcholine transporter (VAChT) is a reliable biomarker for the cholinergic system. We previously reported the initial in vitro and ex vivo characterization of (-)-[(11)C]TZ659 as a VAChT specific ligand. Here, we report the in vivo specificity, tracer kinetics, and dose-occupancy studies in the nonhuman primate brain. METHODS MicroPET brain imaging of (-)-[(11)C]TZ659 was performed under baseline conditions in two male macaques. Tracer kinetic modeling was carried out using a two-tissue compartment model (2TCM) and Logan plot with arterial blood input function and using a simplified reference tissue model (SRTM) and Logan plot (LoganREF) without blood input. Specificity for VAChT was demonstrated by pretreatment with (+)-pentazocine, (-)-vesamicol, or S-(-)-eticlopride. Target occupancy (Occ) was calculated following pretreatment with escalating doses of (-)-vesamicol. RESULTS Baseline PET imaging revealed selective retention in the striatum with rapid clearance from the cerebellar hemispheres as a reference region. Total volume of distribution (VT) values derived from both 2TCM and Logan analysis with blood input revealed ~3-fold higher levels of (-)-[(11)C]TZ659 in the striatum than the cerebellar hemispheres. Injection of (-)-vesamicol either as a blocking or displacing agent significantly reduced striatal uptake of (-)-[(11)C]TZ659. In contrast, pretreatment with the sigma-1 ligand (+)-pentazocine had no impact. Pretreatment with the S-(-)-eticlopride, a dopamine D2-like receptor antagonist, increased striatal uptake of (-)-[(11)C]TZ659. Striatal binding potential (BPND, range of 0.33-1.6 with cerebellar hemispheres as the reference region) showed good correlation (r(2)=0.97) between SRTM and LoganREF. Occupancy studies found that ~0.0057 mg/kg of (-)-vesamicol produced 50% VAChT occupancy in the striatum. CONCLUSION (-)-[(11)C]TZ659 demonstrated specific and reversible VAChT binding and favorable pharmacokinetic properties for assessing the density of VAChT in the living brain.
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Affiliation(s)
- Hongjun Jin
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Xiang Zhang
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Xuyi Yue
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hui Liu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Junfeng Li
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hao Yang
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hubert Flores
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Yi Su
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Stanley M Parsons
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, USA
| | - Joel S Perlmutter
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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29
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Tu Z, Zhang X, Jin H, Yue X, Padakanti PK, Yu L, Liu H, Flores HP, Kaneshige K, Parsons SM, Perlmutter JS. Synthesis and biological characterization of a promising F-18 PET tracer for vesicular acetylcholine transporter. Bioorg Med Chem 2015; 23:4699-4709. [PMID: 26138195 DOI: 10.1016/j.bmc.2015.05.058] [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] [Received: 04/13/2015] [Revised: 05/22/2015] [Accepted: 05/28/2015] [Indexed: 12/14/2022]
Abstract
Nine fluorine-containing vesicular acetylcholine transporter (VAChT) inhibitors were synthesized and screened as potential PET tracers for imaging the VAChT. Compound 18a was one of the most promising carbonyl-containing benzovesamicol analogs; the minus enantiomer, (-)-18a displayed high potency (VAChT Ki=0.59 ± 0.06 nM) and high selectivity for VAChT versus σ receptors (>10,000-fold). The radiosynthesis of (-)-[(18)F]18a was accomplished by a two-step procedure with 30-40% radiochemical yield. Preliminary biodistribution studies of (-)-[(18)F]18a in adult male Sprague-Dawley rats at 5, 30, 60 and 120 min post-injection (p.i.) were promising. The total brain uptake of (-)-[(18)F]18a was 0.684%ID/g at 5 min p.i. and by 120 min p.i. slowly washed out to 0.409 %ID/g; evaluation of regional brain uptake showed stable levels of ∼0.800 %ID/g from 5 to 120 min p.i in the VAChT-enriched striatal tissue of rats, indicating the tracer had crossed the blood brain barrier and was retained in the striatum. Subsequent microPET brain imaging studies of (-)-[(18)F]18a in nonhuman primates (NHPs) showed high striatal accumulation in the NHP brain; the standardized uptake value (SUV) for striatum reached a maximum value of 5.1 at 15 min p.i. The time-activity curve for the target striatal region displayed a slow and gradual decreasing trend 15 min after injection, while clearance of the radioactivity from the cerebellar reference region was much more rapid. Pretreatment of NHPs with 0.25mg/kg of the VAChT inhibitor (-)-vesamicol resulted in a ∼90% decrease of striatal uptake compared to baseline studies. HPLC metabolite analysis of NHP plasma revealed that (-)-[(18)F]18a had a good in vivo stability. Together, these preliminary results suggest (-)-[(18)F]18a is a promising PET tracer candidate for imaging VAChT in the brain of living subjects.
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Affiliation(s)
- Zhude Tu
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO 63110, USA.
| | - Xiang Zhang
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO 63110, USA
| | - Hongjun Jin
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO 63110, USA
| | - Xuyi Yue
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO 63110, USA
| | - Prashanth K Padakanti
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO 63110, USA
| | - Lihai Yu
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO 63110, USA
| | - Hui Liu
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO 63110, USA
| | - Hubert P Flores
- Department of Neurology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO 63110, USA
| | - Kota Kaneshige
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, USA
| | - Stanley M Parsons
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, USA
| | - Joel S Perlmutter
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO 63110, USA; Department of Neurology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO 63110, USA
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30
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Nanoparticle-mediated growth factor delivery systems: A new way to treat Alzheimer's disease. J Control Release 2015; 206:187-205. [DOI: 10.1016/j.jconrel.2015.03.024] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 03/19/2015] [Accepted: 03/20/2015] [Indexed: 01/03/2023]
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31
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Liu H, Jin H, Li J, Zhang X, Kaneshige K, Parsons SM, Perlmutter JS, Tu Z. In vitro and ex vivo characterization of (-)-TZ659 as a ligand for imaging the vesicular acetylcholine transporter. Eur J Pharmacol 2015; 752:18-25. [PMID: 25678250 PMCID: PMC4369186 DOI: 10.1016/j.ejphar.2015.02.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 01/30/2015] [Accepted: 02/03/2015] [Indexed: 12/30/2022]
Abstract
The loss of cholinergic neurons and synapses relates to the severity of dementia in several neurodegenerative pathologies; and the vesicular acetylcholine transporter (VAChT) provides a reliable biomarker of cholinergic function. We recently characterized and (11)C-labeled a new VAChT inhibitor, (-)-TZ659. Here we report the in vitro and ex vivo characterization of (-)-TZ659. A stably transfected PC12(A123.7) cell line which expresses human VAChT (hVAChT) was used for the in vitro binding characterization of (-)-[(3)H]TZ659. A saturated binding curve was obtained with Kd=1.97±0.30nM and Bmax=3240±145.9fmol/mg protein. In comparison, a PC12(A123.7) cell line that expresses mutant hVAChT showed decreased binding affinity (Kd=15.94±0.28nM). Competitive binding assays using a panel of other CNS ligands showed no inhibition of (-)-[(3)H]TZ659 binding. On the other hand, binding inhibitions were observed only using VAChT inhibitors (Ki=0.20-31.35nM). An in vitro assay using rat brain homogenates showed that (-)-[(3)H]TZ659 had higher binding in striatum than in cerebellum, with a target: non-target ratio>3.46. Even higher ex vivo striatum-to-cerebellum ratios (9.56±1.11) were observed using filtered homogenates of brain tissue after rats were injected intravenously with (-)-[(11)C]TZ659. Ex vivo autoradiography of (-)-[(11)C]TZ659 confirmed high striatal uptake, with a consistently high striatum-to-cerebellum ratio (2.99±0.44). In conclusion, (-)-TZ659 demonstrated high potency and good specificity for VAChT in vitro and in vivo. These data suggest that (-)-[(11)C]TZ659 may be a promising PET tracer to image VAChT in the brain.
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Affiliation(s)
- Hui Liu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hongjun Jin
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Junfeng Li
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Xiang Zhang
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Kota Kaneshige
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, USA
| | - Stanley M Parsons
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, USA
| | - Joel S Perlmutter
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Zhude Tu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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32
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Lauzon MA, Daviau A, Marcos B, Faucheux N. Growth factor treatment to overcome Alzheimer's dysfunctional signaling. Cell Signal 2015; 27:1025-38. [PMID: 25744541 DOI: 10.1016/j.cellsig.2015.02.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 02/16/2015] [Indexed: 10/23/2022]
Abstract
The number of people suffering from Alzheimer's disease (AD) will increase as the world population ages, creating a huge socio-economic burden. The three pathophysiological hallmarks of AD are the cholinergic system dysfunction, the β-amyloid peptide deposition and the Tau protein hyperphosphorylation. Current treatments have only transient effects and each tends to concentrate on a single pathophysiological aspect of AD. This review first provides an overall view of AD in terms of its pathophysiological symptoms and signaling dysfunction. We then examine the therapeutic potential of growth factors (GFs) by showing how they can overcome the dysfunctional cell signaling that occurs in AD. Finally, we discuss new alternatives to GFs that help overcome the problem of brain uptake, such as small peptides, with evidence from some of our unpublished data on human neuronal cell line.
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Affiliation(s)
- Marc-Antoine Lauzon
- Cell-Biomaterial Biohybrid Systems, Department of Chemical and Biotechnological Engineering, Université de Sherbrooke, 2500 boul. de l'Université, Sherbrooke, Québec J1K 2R1, Canada
| | - Alex Daviau
- Cell-Biomaterial Biohybrid Systems, Department of Chemical and Biotechnological Engineering, Université de Sherbrooke, 2500 boul. de l'Université, Sherbrooke, Québec J1K 2R1, Canada
| | - Bernard Marcos
- Department of Chemical and Biotechnological Engineering, Université de Sherbrooke, 2500 boul. de l'Université, Sherbrooke, Québec J1K 2R1, Canada
| | - Nathalie Faucheux
- Cell-Biomaterial Biohybrid Systems, Department of Chemical and Biotechnological Engineering, Université de Sherbrooke, 2500 boul. de l'Université, Sherbrooke, Québec J1K 2R1, Canada.
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33
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Schilling LP, Leuzy A, Zimmer ER, Gauthier S, Rosa-Neto P. Nonamyloid PET biomarkers and Alzheimer's disease: current and future perspectives. FUTURE NEUROLOGY 2014. [DOI: 10.2217/fnl.14.40] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
ABSTRACT Recent advances in neurobiology and PET have helped redefine Alzheimer's disease (AD) as a dynamic pathophysiological process, clinically characterized by preclinical, mild cognitive impairment due to AD and dementia stages. Though a majority of PET studies conducted within these populations have to date focused on β-amyloid, various ‘nonamyloid’ radiopharmaceuticals exist for evaluating neurodegeneration, neuroinflammation and perturbations in neurotransmission across the spectrum of AD. Importantly, findings using such tracers have been shown to correlate with various clinical, cognitive and behavioral measures. In the context of a growing shift toward early diagnosis and symptomatic and disease-modifying clinical trials, nonamyloid PET radiotracers will prove of use, and, potentially, contribute to improved therapeutic prospects for AD.
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Affiliation(s)
- Lucas Porcello Schilling
- Translational Neuroimaging Laboratory (TNL), McGill Center for Studies in Aging (MCSA), Douglas Mental Health Research Institute, Montreal, Canada
- Alzheimer's Disease Research Unit, McGill Center for Studies in Aging (MCSA), Douglas Mental Health Research Institute, Montreal, Canada
- Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, Brazil
| | - Antoine Leuzy
- Translational Neuroimaging Laboratory (TNL), McGill Center for Studies in Aging (MCSA), Douglas Mental Health Research Institute, Montreal, Canada
- Alzheimer's Disease Research Unit, McGill Center for Studies in Aging (MCSA), Douglas Mental Health Research Institute, Montreal, Canada
| | - Eduardo Rigon Zimmer
- Translational Neuroimaging Laboratory (TNL), McGill Center for Studies in Aging (MCSA), Douglas Mental Health Research Institute, Montreal, Canada
- Alzheimer's Disease Research Unit, McGill Center for Studies in Aging (MCSA), Douglas Mental Health Research Institute, Montreal, Canada
- Department of Biochemistry, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Serge Gauthier
- Alzheimer's Disease Research Unit, McGill Center for Studies in Aging (MCSA), Douglas Mental Health Research Institute, Montreal, Canada
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory (TNL), McGill Center for Studies in Aging (MCSA), Douglas Mental Health Research Institute, Montreal, Canada
- Alzheimer's Disease Research Unit, McGill Center for Studies in Aging (MCSA), Douglas Mental Health Research Institute, Montreal, Canada
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Development of (18)F-labeled radiotracers for neuroreceptor imaging with positron emission tomography. Neurosci Bull 2014; 30:777-811. [PMID: 25172118 DOI: 10.1007/s12264-014-1460-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Accepted: 06/02/2014] [Indexed: 12/14/2022] Open
Abstract
Positron emission tomography (PET) is an in vivo molecular imaging tool which is widely used in nuclear medicine for early diagnosis and treatment follow-up of many brain diseases. PET uses biomolecules as probes which are labeled with radionuclides of short half-lives, synthesized prior to the imaging studies. These probes are called radiotracers. Fluorine-18 is a radionuclide routinely used in the radiolabeling of neuroreceptor ligands for PET because of its favorable half-life of 109.8 min. The delivery of such radiotracers into the brain provides images of transport, metabolic, and neurotransmission processes on the molecular level. After a short introduction into the principles of PET, this review mainly focuses on the strategy of radiotracer development bridging from basic science to biomedical application. Successful radiotracer design as described here provides molecular probes which not only are useful for imaging of human brain diseases, but also allow molecular neuroreceptor imaging studies in various small-animal models of disease, including genetically-engineered animals. Furthermore, they provide a powerful tool for in vivo pharmacology during the process of pre-clinical drug development to identify new drug targets, to investigate pathophysiology, to discover potential drug candidates, and to evaluate the pharmacokinetics and pharmacodynamics of drugs in vivo.
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