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Ali NH, Al‐Kuraishy HM, Al‐Gareeb AI, Alnaaim SA, Alexiou A, Papadakis M, Khalifa AA, Saad HM, Batiha GE. Neprilysin inhibitors and risk of Alzheimer's disease: A future perspective. J Cell Mol Med 2024; 28:e17993. [PMID: 37847125 PMCID: PMC10826440 DOI: 10.1111/jcmm.17993] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 09/15/2023] [Accepted: 10/05/2023] [Indexed: 10/18/2023] Open
Abstract
Alzheimer's disease (AD) is a heterogeneous neurodegenerative disease with multifaceted neuropathological disorders. AD is characterized by intracellular accumulation of phosphorylated tau proteins and extracellular deposition of amyloid beta (Aβ). Various protease enzymes, including neprilysin (NEP), are concerned with the degradation and clearance of Aβ. Indeed, a defective neuronal clearance pathway due to the dysfunction of degradation enzymes might be a possible mechanism for the accumulation of Aβ and subsequent progression of AD neuropathology. NEP is one of the most imperative metalloproteinase enzymes involved in the clearance of Aβ. This review aimed to highlight the possible role of NEP inhibitors in AD. The combination of sacubitril and valsartan which is called angiotensin receptor blocker and NEP inhibitor (ARNI) may produce beneficial and deleterious effects on AD neuropathology. NEP inhibitors might increase the risk of AD by the inhibition of Aβ clearance, and increase brain bradykinin (BK) and natriuretic peptides (NPs), which augment the pathogenesis of AD. These verdicts come from animal model studies, though they may not be applied to humans. However, clinical studies revealed promising safety findings regarding the use of ARNI. Moreover, NEP inhibition increases various neuroprotective peptides involved in inflammation, glucose homeostasis and nerve conduction. Also, NEP inhibitors may inhibit dipeptidyl peptidase 4 (DPP4) expression, ameliorating insulin and glucagon-like peptide 1 (GLP-1) levels. These findings proposed that NEP inhibitors may have a protective effect against AD development by increasing GLP-1, neuropeptide Y (NPY) and substance P, and deleterious effects by increasing brain BK. Preclinical and clinical studies are recommended in this regard.
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Affiliation(s)
- Naif H. Ali
- Department of Internal Medicine, Medical CollegeNajran UniversityNajranSaudi Arabia
| | - Hayder M. Al‐Kuraishy
- Department of Clinical Pharmacology and Medicine, College of MedicineMustansiriyah UniversityBaghdadIraq
| | - Ali I. Al‐Gareeb
- Department of Clinical Pharmacology and Medicine, College of MedicineMustansiriyah UniversityBaghdadIraq
| | - Saud A. Alnaaim
- Clinical Neurosciences Department, College of MedicineKing Faisal UniversityHofufSaudi Arabia
| | - Athanasios Alexiou
- Department of Science and EngineeringNovel Global Community Educational FoundationHebershamNew South WalesAustralia
- AFNP MedWienAustria
| | - Marios Papadakis
- Department of Surgery IIUniversity Hospital Witten‐Herdecke, University of Witten‐HerdeckeWuppertalGermany
| | - Asmaa A. Khalifa
- Department of Pharmacology and Therapeutics, Faculty of PharmacyPharos University in AlexandriaAlexandriaEgypt
| | - Hebatallah M. Saad
- Department of Pathology, Faculty of Veterinary MedicineMatrouh UniversityMatrouhEgypt
| | - Gaber El‐Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary MedicineDamanhour UniversityDamanhourAlBeheiraEgypt
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2
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Hu WT, Nayyar A, Kaluzova M. Charting the Next Road Map for CSF Biomarkers in Alzheimer's Disease and Related Dementias. Neurotherapeutics 2023; 20:955-974. [PMID: 37378862 PMCID: PMC10457281 DOI: 10.1007/s13311-023-01370-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2023] [Indexed: 06/29/2023] Open
Abstract
Clinical prediction of underlying pathologic substrates in people with Alzheimer's disease (AD) dementia or related dementia syndromes (ADRD) has limited accuracy. Etiologic biomarkers - including cerebrospinal fluid (CSF) levels of AD proteins and cerebral amyloid PET imaging - have greatly modernized disease-modifying clinical trials in AD, but their integration into medical practice has been slow. Beyond core CSF AD biomarkers (including beta-amyloid 1-42, total tau, and tau phosphorylated at threonine 181), novel biomarkers have been interrogated in single- and multi-centered studies with uneven rigor. Here, we review early expectations for ideal AD/ADRD biomarkers, assess these goals' future applicability, and propose study designs and performance thresholds for meeting these ideals with a focus on CSF biomarkers. We further propose three new characteristics: equity (oversampling of diverse populations in the design and testing of biomarkers), access (reasonable availability to 80% of people at risk for disease, along with pre- and post-biomarker processes), and reliability (thorough evaluation of pre-analytical and analytical factors influencing measurements and performance). Finally, we urge biomarker scientists to balance the desire and evidence for a biomarker to reflect its namesake function, indulge data- as well as theory-driven associations, re-visit the subset of rigorously measured CSF biomarkers in large datasets (such as Alzheimer's disease neuroimaging initiative), and resist the temptation to favor ease over fail-safe in the development phase. This shift from discovery to application, and from suspended disbelief to cogent ingenuity, should allow the AD/ADRD biomarker field to live up to its billing during the next phase of neurodegenerative disease research.
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Affiliation(s)
- William T Hu
- Department of Neurology, Rutgers Biomedical and Health Sciences, Rutgers-Robert Wood Johnson Medical School, 125 Paterson Street, Suite 6200, New Brunswick, NJ, 08901, USA.
- Center for Innovation in Health and Aging Research, Institute for Health, Health Care Policy, and Aging Research, Rutgers Biomedical and Health Sciences, Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ, 08901, USA.
| | - Ashima Nayyar
- Department of Neurology, Rutgers Biomedical and Health Sciences, Rutgers-Robert Wood Johnson Medical School, 125 Paterson Street, Suite 6200, New Brunswick, NJ, 08901, USA
| | - Milota Kaluzova
- Department of Neurology, Rutgers Biomedical and Health Sciences, Rutgers-Robert Wood Johnson Medical School, 125 Paterson Street, Suite 6200, New Brunswick, NJ, 08901, USA
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3
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Liu YJ, Liu TT, Jiang LH, Liu Q, Ma ZL, Xia TJ, Gu XP. Identification of hub genes associated with cognition in the hippocampus of Alzheimer's Disease. Bioengineered 2021; 12:9598-9609. [PMID: 34719328 PMCID: PMC8810106 DOI: 10.1080/21655979.2021.1999549] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Alzheimer’s Disease (AD) is a neurodegenerative disease featured by cognitive impairment. This bioinformatic analysis was used to identify hub genes related to cognitive dysfunction in AD. The gene expression profile GSE48350 in the hippocampus of AD patients aged >70 years was obtained from the Gene Expression Omnibus (GEO) database. A total of 96 differentially expressed genes (DEGs) were identified, and subjected to Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses; a protein–protein interaction (PPI) network was constructed. The DEGs were enriched in synapse-related changes. A protein cluster was teased out of PPI. Furthermore, the cognition ranked the first among all the terms of biological process (BP). Next, 4 of 10 hub genes enriched in cognition were identified. The function of these genes was validated using APP/PS1 mice. Cognitive performance was validated by Morris Water Maze (MWM), and gene expression by RT-qPCR, Cholecystokinin (CCK), Tachykinin precursor 1 (TAC1), Calbindin 1 (CALB1) were downregulated in the hippocampus. These genes can provide new directions in the research of the molecular mechanism of AD.
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Affiliation(s)
- Yu-Jia Liu
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu Province, China.,Medical School of Nanjing University, Nanjing, Jiangsu Province, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Tian-Tian Liu
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu Province, China.,Medical School of Nanjing University, Nanjing, Jiangsu Province, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Lin-Hao Jiang
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu Province, China.,Medical School of Nanjing University, Nanjing, Jiangsu Province, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Qian Liu
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu Province, China.,Medical School of Nanjing University, Nanjing, Jiangsu Province, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Zheng-Liang Ma
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu Province, China
| | - Tian-Jiao Xia
- Medical School of Nanjing University, Nanjing, Jiangsu Province, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Xiao-Ping Gu
- Department of Anesthesiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu Province, China
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4
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Ben-Shushan S, Miller Y. Neuropeptides: Roles and Activities as Metal Chelators in Neurodegenerative Diseases. J Phys Chem B 2021; 125:2796-2811. [PMID: 33570949 PMCID: PMC8389909 DOI: 10.1021/acs.jpcb.0c11151] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD), are characterized by deposits of amyloid proteins. The homeostasis of metal ions is crucial for the normal biological functions in the brain. However, in AD and PD, the imbalance of metal ions leads to formation of amyloid deposits. In the past four decades, there has been extensive effort to design compound agents than can chelate metal ions with the aim of preventing the formation of the amyloid deposits. Unfortunately, the compounds to date that were designed were not successful candidates to be used in clinical trials. Neuropeptides are small molecules that are produced and released by neurons. It has been shown that neuropeptides have neuroprotective effects in the brain and reduce the formation of amyloid deposits. This Review Article is focused on the function of neuropeptides as metal chelators. Experimental and computational studies demonstrated that neuropeptides could bind metal ions, such as Cu2+ and Zn2+. This Review Article provides perspectives and initiates future studies to investigate the role of neuropeptides as metal chelators in neurodegenerative diseases.
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Affiliation(s)
- Shira Ben-Shushan
- Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Be'er Sheva 84105, Israel.,Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er Sheva 84105, Israel
| | - Yifat Miller
- Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Be'er Sheva 84105, Israel.,Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er Sheva 84105, Israel
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5
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Petrella C, Di Certo MG, Barbato C, Gabanella F, Ralli M, Greco A, Possenti R, Severini C. Neuropeptides in Alzheimer’s Disease: An Update. Curr Alzheimer Res 2019; 16:544-558. [DOI: 10.2174/1567205016666190503152555] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/19/2019] [Accepted: 04/30/2019] [Indexed: 12/19/2022]
Abstract
Neuropeptides are small proteins broadly expressed throughout the central nervous system, which act as neurotransmitters, neuromodulators and neuroregulators. Growing evidence has demonstrated the involvement of many neuropeptides in both neurophysiological functions and neuropathological conditions, among which is Alzheimer’s disease (AD). The role exerted by neuropeptides in AD is endorsed by the evidence that they are mainly neuroprotective and widely distributed in brain areas responsible for learning and memory processes. Confirming this point, it has been demonstrated that numerous neuropeptide-containing neurons are pathologically altered in brain areas of both AD patients and AD animal models. Furthermore, the levels of various neuropeptides have been found altered in both Cerebrospinal Fluid (CSF) and blood of AD patients, getting insights into their potential role in the pathophysiology of AD and offering the possibility to identify novel additional biomarkers for this pathology. We summarized the available information about brain distribution, neuroprotective and cognitive functions of some neuropeptides involved in AD. The main focus of the current review was directed towards the description of clinical data reporting alterations in neuropeptides content in both AD patients and AD pre-clinical animal models. In particular, we explored the involvement in the AD of Thyrotropin-Releasing Hormone (TRH), Cocaine- and Amphetamine-Regulated Transcript (CART), Cholecystokinin (CCK), bradykinin and chromogranin/secretogranin family, discussing their potential role as a biomarker or therapeutic target, leaving the dissertation of other neuropeptides to previous reviews.
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Affiliation(s)
- Carla Petrella
- Department of Sense Organs, CNR, Institute of Cell Biology and Neurobiology, University Sapienza of Rome, Viale del Policlinico 155, 00161 Rome, Italy
| | - Maria Grazia Di Certo
- Department of Sense Organs, CNR, Institute of Cell Biology and Neurobiology, University Sapienza of Rome, Viale del Policlinico 155, 00161 Rome, Italy
| | - Christian Barbato
- Department of Sense Organs, CNR, Institute of Cell Biology and Neurobiology, University Sapienza of Rome, Viale del Policlinico 155, 00161 Rome, Italy
| | - Francesca Gabanella
- Department of Sense Organs, CNR, Institute of Cell Biology and Neurobiology, University Sapienza of Rome, Viale del Policlinico 155, 00161 Rome, Italy
| | - Massimo Ralli
- Department of Sense Organs, University Sapienza of Rome, Viale del Policlinico 155, 00161 Rome, Italy
| | - Antonio Greco
- Department of Sense Organs, University Sapienza of Rome, Viale del Policlinico 155, 00161 Rome, Italy
| | - Roberta Possenti
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Cinzia Severini
- Department of Sense Organs, CNR, Institute of Cell Biology and Neurobiology, University Sapienza of Rome, Viale del Policlinico 155, 00161 Rome, Italy
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6
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Chen XY, Du YF, Chen L. Neuropeptides Exert Neuroprotective Effects in Alzheimer's Disease. Front Mol Neurosci 2019; 11:493. [PMID: 30687008 PMCID: PMC6336706 DOI: 10.3389/fnmol.2018.00493] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 12/21/2018] [Indexed: 01/03/2023] Open
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disorder characterized by cognitive deficits and neuronal loss. Deposition of beta-amyloid peptide (Aβ) causes neurotoxicity through the formation of plaques in brains of Alzheimer's disease. Numerous studies have indicated that the neuropeptides including ghrelin, neurotensin, pituitary adenylate cyclase-activating polypeptide (PACAP), neuropeptide Y, substance P and orexin are closely related to the pathophysiology of Alzheimer's disease. The levels of neuropeptides and their receptors change in Alzheimer's disease. These neuropeptides exert neuroprotective roles mainly through preventing Aβ accumulation, increasing neuronal glucose transport, increasing the production of neurotrophins, inhibiting endoplasmic reticulum stress and autophagy, modulating potassium channel activity and hippocampal long-term potentiation. Therefore, the neuropeptides may function as potential drug targets in the prevention and cure of Alzheimer's disease.
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Affiliation(s)
- Xin-Yi Chen
- Department of Physiology and Pathophysiology, Qingdao University, Qingdao, China.,Department of Neurology, Provincial Hospital Affiliated to Shandong University, Jinan, China
| | - Yi-Feng Du
- Department of Neurology, Provincial Hospital Affiliated to Shandong University, Jinan, China
| | - Lei Chen
- Department of Physiology and Pathophysiology, Qingdao University, Qingdao, China
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7
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Borbély E, Scheich B, Helyes Z. Neuropeptides in learning and memory. Neuropeptides 2013; 47:439-50. [PMID: 24210137 DOI: 10.1016/j.npep.2013.10.012] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 10/14/2013] [Accepted: 10/14/2013] [Indexed: 12/14/2022]
Abstract
Dementia conditions and memory deficits of different origins (vascular, metabolic and primary neurodegenerative such as Alzheimer's and Parkinson's diseases) are getting more common and greater clinical problems recently in the aging population. Since the presently available cognitive enhancers have very limited therapeutical applications, there is an emerging need to elucidate the complex pathophysiological mechanisms, identify key mediators and novel targets for future drug development. Neuropeptides are widely distributed in brain regions responsible for learning and memory processes with special emphasis on the hippocampus, amygdala and the basal forebrain. They form networks with each other, and also have complex interactions with the cholinergic, glutamatergic, dopaminergic and GABA-ergic pathways. This review summarizes the extensive experimental data in the well-established rat and mouse models, as well as the few clinical results regarding the expression and the roles of the tachykinin system, somatostatin and the closely related cortistatin, vasoactive intestinal polypeptide (VIP) and pituitary adenylate-cyclase activating polypeptide (PACAP), calcitonin gene-related peptide (CGRP), neuropeptide Y (NPY), opioid peptides and galanin. Furthermore, the main receptorial targets, mechanisms and interactions are described in order to highlight the possible therapeutical potentials. Agents not only symptomatically improving the functional impairments, but also inhibiting the progression of the neurodegenerative processes would be breakthroughs in this area. The most promising mechanisms determined at the level of exploratory investigations in animal models of cognitive disfunctions are somatostatin sst4, NPY Y2, PACAP-VIP VPAC1, tachykinin NK3 and galanin GALR2 receptor agonisms, as well as delta opioid receptor antagonism. Potent and selective non-peptide ligands with good CNS penetration are needed for further characterization of these molecular pathways to complete the preclinical studies and decide if any of the above described targets could be appropriate for clinical investigations.
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Affiliation(s)
- Eva Borbély
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Pécs, Szigeti u. 12, H-7624 Pécs, Hungary; Molecular Pharmacology Research Group, János Szentágothai Research Center, University of Pécs, Ifjúság útja 20, H-7624 Pécs, Hungary
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8
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Midregional Proenkephalin A and N-terminal Protachykinin A are decreased in the cerebrospinal fluid of patients with dementia disorders and acute neuroinflammation. J Neuroimmunol 2010; 221:62-7. [DOI: 10.1016/j.jneuroim.2010.02.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 02/03/2010] [Accepted: 02/03/2010] [Indexed: 11/18/2022]
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9
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Ernst A, Suhr J, Köhrle J, Bergmann A. Detection of stable N-terminal protachykinin A immunoreactivity in human plasma and cerebrospinal fluid. Peptides 2008; 29:1201-6. [PMID: 18374454 DOI: 10.1016/j.peptides.2008.02.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2008] [Revised: 02/03/2008] [Accepted: 02/13/2008] [Indexed: 10/22/2022]
Abstract
Substance P (SP) is a neuropeptide that is released from sensory nerves and several types of immune cells. It is involved in the transmission of pain and has a number of pro-inflammatory effects. Like other neuropeptides, SP is derived from a large precursor peptide, protachykinin A (PTA). Alternative splicing results in the production of four distinct PTA molecules that all contain the sequence of SP and a common N-terminal region consisting of 37 amino acids. We have developed a sandwich immunoassay using antibodies against the N-terminal part of PTA. Here we demonstrate that N-terminal PTA immunoreactivity is present in human circulation and cerebrospinal fluid (CSF). The concentration was about 90 times higher in CSF than in EDTA-plasma. Analytical reversed phase HPLC revealed that NT-PTA 1-37 is the main immunoreactivity in human circulation and CSF. Moreover, compared to the low in vitro stability of SP of less than 12 min, NT-PTA immunoreactivity is absolutely stable in EDTA-plasma and CSF for more than 48 h. As NT-PTA 1-37 is produced in stoichiometric amounts and is theoretically co-released with SP, we suggest the measurement of NT-PTA immunoreactivity as surrogate molecule for the release of bioactive SP.
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Affiliation(s)
- Andrea Ernst
- SphingoTec GmbH, Tulpenweg 6, D-16556 Borgsdorf, Germany.
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Le-Niculescu H, Balaraman Y, Patel S, Tan J, Sidhu K, Jerome RE, Edenberg HJ, Kuczenski R, Geyer MA, Nurnberger JI, Faraone SV, Tsuang MT, Niculescu AB. Towards understanding the schizophrenia code: an expanded convergent functional genomics approach. Am J Med Genet B Neuropsychiatr Genet 2007; 144B:129-58. [PMID: 17266109 DOI: 10.1002/ajmg.b.30481] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Identifying genes for schizophrenia through classical genetic approaches has proven arduous. Here, we present a comprehensive convergent analysis that translationally integrates brain gene expression data from a relevant pharmacogenomic mouse model (involving treatments with a psychomimetic agent - phencyclidine (PCP), and an anti-psychotic - clozapine), with human genetic linkage data and human postmortem brain data, as a Bayesian strategy of cross validating findings. Topping the list of candidate genes, we have three genes involved in GABA neurotransmission (GABRA1, GABBR1, and GAD2), one gene involved in glutamate neurotransmission (GRIA2), one gene involved in neuropeptide signaling (TAC1), two genes involved in synaptic function (SYN2 and KCNJ4), six genes involved in myelin/glial function (CNP, MAL, MBP, PLP1, MOBP and GFAP), and one gene involved in lipid metabolism (LPL). These data suggest that schizophrenia is primarily a disorder of brain functional and structural connectivity, with GABA neurotransmission playing a prominent role. These findings may explain the EEG gamma band abnormalities detected in schizophrenia. The analysis also revealed other high probability candidates genes (neurotransmitter signaling, other structural proteins, ion channels, signal transduction, regulatory enzymes, neuronal migration/neurite outgrowth, clock genes, transcription factors, RNA regulatory genes), pathways and mechanisms of likely importance in pathophysiology. Some of the pathways identified suggest possible avenues for augmentation pharmacotherapy of schizophrenia with other existing agents, such as benzodiazepines, anticonvulsants and lipid modulating agents. Other pathways are new potential targets for drug development. Lastly, a comparison with our earlier work on bipolar disorder illuminates the significant molecular overlap between schizophrenia and bipolar disorder.
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Affiliation(s)
- H Le-Niculescu
- Laboratory of Neurophenomics, Indiana University School of Medicine, Indianapolis, Indiana, USA
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