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Fidalgo S, Yeoman MS. Age-Related Changes in Central Nervous System 5-Hydroxytryptamine Signalling and Its Potential Effects on the Regulation of Lifespan. Subcell Biochem 2023; 102:379-413. [PMID: 36600141 DOI: 10.1007/978-3-031-21410-3_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Serotonin or 5-hydroxytryptamine (5-HT) is an important neurotransmitter in the central nervous system and the periphery. Most 5-HT (~99%) is found in the periphery where it regulates the function of the gastrointestinal (GI) tract and is an important regulator of platelet aggregation. However, the remaining 1% that is found in the central nervous system (CNS) can regulate a range of physiological processes such as learning and memory formation, mood, food intake, sleep, temperature and pain perception. More recent work on the CNS of invertebrate model systems has shown that 5-HT can directly regulate lifespan.This chapter will focus on detailing how CNS 5-HT signalling is altered with increasing age and the potential consequences this has on its ability to regulate lifespan.
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Affiliation(s)
| | - Mark S Yeoman
- Centre for Stress and Age-Related Disease, School of Applied Sciences, University of Brighton, Brighton, United Kingdom.
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2
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Gauvreau NL, Bragg LM, Dhiyebi HA, Servos MR, Craig PM. Impacts on antioxidative enzymes and transcripts in darter (Etheostoma spp.) brains in the Grand River exposed to wastewater effluent. Comp Biochem Physiol C Toxicol Pharmacol 2022; 258:109381. [PMID: 35605930 DOI: 10.1016/j.cbpc.2022.109381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 05/06/2022] [Accepted: 05/17/2022] [Indexed: 11/22/2022]
Abstract
The Grand River watershed is the largest in southern Ontario and assimilates thirty wastewater treatment plants (WWTP) with varied degrees of treatment. Many WWTPs are unable to effectively eliminate several contaminants of emerging concern (CECs) from final effluent, leading to measurable concentrations in surface waters. Exposures to CECs have reported impacts on oxidative stress measured through antioxidative enzymes (SOD, CAT, GPX). This study focuses on the effects of WWTP effluent on four Etheostoma (Darter) species endemic to the Grand River, by investigating if increased antioxidative response markers are present in darter brains downstream from the effluent outfall compared to an upstream reference site relative to the Waterloo, ON WWTP across two separate years (Oct 2020 and Oct 2021). This was assessed using transcriptional and enzyme analysis of antioxidant enzymes and an enzyme involved in serotonin synthesis, tryptophan hydroxylase (tph). In fall 2020, significant differences in transcript markers were found between sites and sexes in GSD with SOD and CAT showing increased expression downstream, in JD with both sexes showing increased SOD downstream, and an interactive effect for tph in RBD. Changes in transcripts aligned with enzyme activity where interactive effects with sex-related differences were observed in fish collected fall 2020. In contrast, transcripts measured in fall 2021 were increased upstream compared to downstream species in RBD and GSD. This study additionally displayed yearly, species and sex differences in antioxidant responses. Continued investigation on the impacts of CECs in effluent in non-target species is required to better understand WWTP effluent impacts.
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Affiliation(s)
- Nicole L Gauvreau
- Department of Biology, University of Waterloo, 200 University Ave W, Waterloo, ON N2L 3G1, Canada.
| | - Leslie M Bragg
- Department of Biology, University of Waterloo, 200 University Ave W, Waterloo, ON N2L 3G1, Canada
| | - Hadi A Dhiyebi
- Department of Biology, University of Waterloo, 200 University Ave W, Waterloo, ON N2L 3G1, Canada
| | - Mark R Servos
- Department of Biology, University of Waterloo, 200 University Ave W, Waterloo, ON N2L 3G1, Canada
| | - Paul M Craig
- Department of Biology, University of Waterloo, 200 University Ave W, Waterloo, ON N2L 3G1, Canada
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3
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Ribeiro LW, Pietri M, Ardila-Osorio H, Baudry A, Boudet-Devaud F, Bizingre C, Arellano-Anaya ZE, Haeberlé AM, Gadot N, Boland S, Devineau S, Bailly Y, Kellermann O, Bencsik A, Schneider B. Titanium dioxide and carbon black nanoparticles disrupt neuronal homeostasis via excessive activation of cellular prion protein signaling. Part Fibre Toxicol 2022; 19:48. [PMID: 35840975 PMCID: PMC9284759 DOI: 10.1186/s12989-022-00490-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 06/29/2022] [Indexed: 11/16/2022] Open
Abstract
Background Epidemiological emerging evidence shows that human exposure to some nanosized materials present in the environment would contribute to the onset and/or progression of Alzheimer’s disease (AD). The cellular and molecular mechanisms whereby nanoparticles would exert some adverse effects towards neurons and take part in AD pathology are nevertheless unknown. Results Here, we provide the prime evidence that titanium dioxide (TiO2) and carbon black (CB) nanoparticles (NPs) bind the cellular form of the prion protein (PrPC), a plasma membrane protein well known for its implication in prion diseases and prion-like diseases, such as AD. The interaction between TiO2- or CB-NPs and PrPC at the surface of neuronal cells grown in culture corrupts PrPC signaling function. This triggers PrPC-dependent activation of NADPH oxidase and subsequent production of reactive oxygen species (ROS) that alters redox equilibrium. Through PrPC interaction, NPs also promote the activation of 3-phosphoinositide-dependent kinase 1 (PDK1), which in turn provokes the internalization of the neuroprotective TACE α-secretase. This diverts TACE cleavage activity away from (i) TNFα receptors (TNFR), whose accumulation at the plasma membrane augments the vulnerability of NP-exposed neuronal cells to TNFα -associated inflammation, and (ii) the amyloid precursor protein APP, leading to overproduction of neurotoxic amyloid Aβ40/42 peptides. The silencing of PrPC or the pharmacological inhibition of PDK1 protects neuronal cells from TiO2- and CB-NPs effects regarding ROS production, TNFα hypersensitivity, and Aβ rise. Finally, we show that dysregulation of the PrPC-PDK1-TACE pathway likely occurs in the brain of mice injected with TiO2-NPs by the intra-cerebro-ventricular route as we monitor a rise of TNFR at the cell surface of several groups of neurons located in distinct brain areas. Conclusion Our in vitro and in vivo study thus posits for the first time normal cellular prion protein PrPC as being a neuronal receptor of TiO2- and CB-NPs and identifies PrPC-coupled signaling pathways by which those nanoparticles alter redox equilibrium, augment the intrinsic sensitivity of neurons to neuroinflammation, and provoke a rise of Aβ peptides. By identifying signaling cascades dysregulated by TiO2- and CB-NPs in neurons, our data shed light on how human exposure to some NPs might be related to AD. Supplementary Information The online version contains supplementary material available at 10.1186/s12989-022-00490-x.
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Affiliation(s)
- Luiz W Ribeiro
- INSERM, UMR-S 1124, 75006, Paris, France.,UMR-S 1124, Université Paris Cité, 75006, Paris, France
| | - Mathéa Pietri
- INSERM, UMR-S 1124, 75006, Paris, France.,UMR-S 1124, Université Paris Cité, 75006, Paris, France
| | - Hector Ardila-Osorio
- INSERM, UMR-S 1124, 75006, Paris, France.,UMR-S 1124, Université Paris Cité, 75006, Paris, France
| | - Anne Baudry
- INSERM, UMR-S 1124, 75006, Paris, France.,UMR-S 1124, Université Paris Cité, 75006, Paris, France
| | - François Boudet-Devaud
- INSERM, UMR-S 1124, 75006, Paris, France.,UMR-S 1124, Université Paris Cité, 75006, Paris, France
| | - Chloé Bizingre
- INSERM, UMR-S 1124, 75006, Paris, France.,UMR-S 1124, Université Paris Cité, 75006, Paris, France
| | - Zaira E Arellano-Anaya
- INSERM, UMR-S 1124, 75006, Paris, France.,UMR-S 1124, Université Paris Cité, 75006, Paris, France
| | - Anne-Marie Haeberlé
- Institut Des Neurosciences Cellulaires Et Intégratives, CNRS UPR 3212, Université de Strasbourg, 67084, Strasbourg, France
| | - Nicolas Gadot
- Plateforme Anatomopathologie Recherche, INSERM 1052, CNRS 5286, Centre Léon Bérard, Centre de Recherche en Cancérologie de Lyon (CRCL), Université Claude Bernard Lyon 1, Université de Lyon, 69373, Lyon, France
| | - Sonja Boland
- CNRS UMR 8251, Unité de Biologie Fonctionnelle Et Adaptative, Université Paris Cité, 75013, Paris, France
| | - Stéphanie Devineau
- CNRS UMR 8251, Unité de Biologie Fonctionnelle Et Adaptative, Université Paris Cité, 75013, Paris, France
| | - Yannick Bailly
- Institut Des Neurosciences Cellulaires Et Intégratives, CNRS UPR 3212, Université de Strasbourg, 67084, Strasbourg, France
| | - Odile Kellermann
- INSERM, UMR-S 1124, 75006, Paris, France.,UMR-S 1124, Université Paris Cité, 75006, Paris, France
| | - Anna Bencsik
- ANSES Laboratoire de Lyon, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Claude Bernard Lyon 1, 69364, Lyon, France
| | - Benoit Schneider
- INSERM, UMR-S 1124, 75006, Paris, France. .,UMR-S 1124, Université Paris Cité, 75006, Paris, France.
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4
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Annunziato M, Eeza MNH, Bashirova N, Lawson A, Matysik J, Benetti D, Grosell M, Stieglitz JD, Alia A, Berry JP. An integrated systems-level model of the toxicity of brevetoxin based on high-resolution magic-angle spinning nuclear magnetic resonance (HRMAS NMR) metabolic profiling of zebrafish embryos. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 803:149858. [PMID: 34482148 DOI: 10.1016/j.scitotenv.2021.149858] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 08/18/2021] [Accepted: 08/19/2021] [Indexed: 06/13/2023]
Abstract
Brevetoxins (PbTx) are a well-recognized group of neurotoxins associated with harmful algal blooms, and specifically recurrent "Florida Red Tides," in marine waters that are linked to impacts on both human and ecosystem health including well-documented "fish kills" and marine mammal mortalities in affected coastal waters. Understanding mechanisms and pathways of PbTx toxicity enables identification of relevant biomarkers to better understand these environmental impacts, and improve monitoring efforts, in relation to this toxin. Toward a systems-level understanding of toxicity, and identification of potential biomarkers, high-resolution magic angle spinning nuclear magnetic resonance (HRMAS NMR) was utilized for metabolic profiling of zebrafish (Danio rerio) embryos, as an established toxicological model, exposed to PbTx-2 (the most common congener in marine waters). Metabolomics studies were, furthermore, complemented by an assessment of the toxicity of PbTx-2 in embryonic stages of zebrafish and mahi-mahi (Coryphaena hippurus), the latter representing an ecologically and geographically relevant marine species of fish, which identified acute embryotoxicity at environmentally relevant (i.e., parts-per-billion) concentrations in both species. HRMAS NMR analysis of intact zebrafish embryos exposed to sub-lethal concentrations of PbTx-2 afforded well-resolved spectra, and in turn, identification of 38 metabolites of which 28 were found to be significantly altered, relative to controls. Metabolites altered by PbTx-2 exposure specifically included those associated with (1) neuronal excitotoxicity, as well as associated neural homeostasis, and (2) interrelated pathways of carbohydrate and energy metabolism. Metabolomics studies, thereby, enabled a systems-level model of PbTx toxicity which integrated multiple metabolic, molecular and cellular pathways, in relation to environmentally relevant concentrations of the toxin, providing insight to not only targets and mechanisms, but potential biomarkers pertinent to environmental risk assessment and monitoring strategies.
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Affiliation(s)
- Mark Annunziato
- Institute of Environment, Department of Chemistry and Biochemistry, Florida International University, 3000 NE 151st Street, North Miami, FL 33181, USA
| | - Muhamed N H Eeza
- Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany; Institute for Analytical Chemistry, University of Leipzig, Leipzig, Germany
| | - Narmin Bashirova
- Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany; Institute for Analytical Chemistry, University of Leipzig, Leipzig, Germany
| | - Ariel Lawson
- Institute of Environment, Department of Chemistry and Biochemistry, Florida International University, 3000 NE 151st Street, North Miami, FL 33181, USA
| | - Jörg Matysik
- Institute for Analytical Chemistry, University of Leipzig, Leipzig, Germany
| | - Daniel Benetti
- Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL, USA
| | - Martin Grosell
- Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL, USA
| | - John D Stieglitz
- Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL, USA
| | - A Alia
- Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany; Leiden Institute of Chemistry, Leiden University, 2333 Leiden, the Netherlands.
| | - John P Berry
- Institute of Environment, Department of Chemistry and Biochemistry, Florida International University, 3000 NE 151st Street, North Miami, FL 33181, USA; Biomolecular Science Institute, Florida International University, 11200 SW 8th Street, Miami, FL 33199, USA.
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5
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DeKorver NW, Lichty D, van der Hart M, Rassoulpour A, Bonasera SJ. Increased whole cerebellar serotonin in aged C57BL/6 mice. ACTA ACUST UNITED AC 2017; 2017. [PMID: 28894740 DOI: 10.19185/matters.201702000011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Mobility and locomotor impairments have high prevalence, morbidity, and significant mortality in older adult populations. Cerebellar functional changes have been implicated in the pathogenesis of these age-related mobility and gait deficits unrelated to stroke, Parkinson's disease, or degenerative joint disease. We thus examined total cerebellar glutamate, glutamine, GABA, glycine, dopamine, norepinephrine, tryptophan, serotonin, alanine, threonine, and asparagine content from male 2-3-month (young, n = 6) and 21-24-month-old (aged, n = 6) C57BL/6 mice. Neurotransmitter and amino acid concentrations were determined by high-performance liquid chromatography followed with mass spectroscopy. We found a significant increase in cerebellar serotonin in aged versus young mice, but otherwise no significant phenotypic differences in measured neurotransmitter concentrations. Applying current thought about cerebellar aging and cerebellar serotonergic systems, we consider how this age-related increase in cerebellar serotonin may contribute to gait ataxia.
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Affiliation(s)
- Nicholas W DeKorver
- Internal Medicine, University of Nebraska Medical Center; Microdialysis, Brains Online
| | - Dustin Lichty
- Internal Medicine, University of Nebraska Medical Center; Microdialysis, Brains Online
| | - Marieke van der Hart
- Internal Medicine, University of Nebraska Medical Center; Microdialysis, Brains Online
| | - Arash Rassoulpour
- Internal Medicine, University of Nebraska Medical Center; Microdialysis, Brains Online
| | - Stephen J Bonasera
- Internal Medicine, University of Nebraska Medical Center; Microdialysis, Brains Online
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6
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Changes of tryptophan metabolism in Japanese runners during an ultra-marathon race. SPORT SCIENCES FOR HEALTH 2016. [DOI: 10.1007/s11332-016-0257-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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7
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Reddy MY, Jagota A. Melatonin has differential effects on age-induced stoichiometric changes in daily chronomics of serotonin metabolism in SCN of male Wistar rats. Biogerontology 2014; 16:285-302. [DOI: 10.1007/s10522-014-9545-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 11/27/2014] [Indexed: 11/28/2022]
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8
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Rahman MS, Thomas P. Restoration of tryptophan hydroxylase functions and serotonin content in the Atlantic croaker hypothalamus by antioxidant treatment during hypoxic stress. Front Neurosci 2014; 8:130. [PMID: 24910592 PMCID: PMC4038761 DOI: 10.3389/fnins.2014.00130] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2014] [Accepted: 05/09/2014] [Indexed: 01/21/2023] Open
Abstract
Antioxidants are prototypical scavengers of oxygen-free radicals and have been shown to prevent neuroendocrine dysfunction in vertebrates during oxidative stress. In the present study, we investigated whether antioxidant treatment can reverse hypoxia-induced down-regulation of hypothalamic tryptophan hydroxylase (TPH) and serotonergic functions in Atlantic croaker. Hypothalamic neuronal contents of TPH-1 and TPH-2 proteins, serotonin (5-hydroxytryptamine, 5-HT) and its precursor, 5-hydroxytryptophan (5-HTP) as well as hypothalamic TPH-1 and TPH-2 mRNA expression and TPH activity were measured in croaker after exposure to hypoxia and treatment with pharmacological agents. Multiple injections of N-ethylmaleimide, a sulfhydryl alkylating agent, caused comparable decreases in hypothalamic TPHs functions and 5-HT contents to that induced by hypoxia exposure (dissolved oxygen: 1.7 mg/L for 4 weeks) which were partially restored by repeated injections with a nitric oxide synthase (NOS)-inhibitor and/or vitamin E. Double-labeled immunohistochemical results showed that TPHs and 5-HT neurons were co-expressed with neuronal NOS (nNOS, a neuroenzyme) that catalyzes the production of nitric oxide, a free radical, in hypothalamic neurons. These results suggest that hypoxia-induced impairment of TPH and serotonergic functions are mediated by nNOS and involve the generation of free radicals and a decrease in the antioxidant status. This study provides, to our knowledge, the first evidence of a protective role for an antioxidant in maintaining neural TPHs functions and 5-HT regulation in an aquatic vertebrate during hypoxic stress.
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Affiliation(s)
- Md Saydur Rahman
- Marine Science Institute, University of Texas at Austin Port Aransas, TX, USA
| | - Peter Thomas
- Marine Science Institute, University of Texas at Austin Port Aransas, TX, USA
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9
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Intake of melatonin increases tryptophan hydroxylase type 1 activity in aged rats: Preliminary study. Exp Gerontol 2014; 49:1-4. [DOI: 10.1016/j.exger.2013.10.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 10/15/2013] [Accepted: 10/24/2013] [Indexed: 11/22/2022]
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10
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Bravo R, Matito S, Cubero J, Paredes SD, Franco L, Rivero M, Rodríguez AB, Barriga C. Tryptophan-enriched cereal intake improves nocturnal sleep, melatonin, serotonin, and total antioxidant capacity levels and mood in elderly humans. AGE (DORDRECHT, NETHERLANDS) 2013; 35:1277-85. [PMID: 22622709 PMCID: PMC3705114 DOI: 10.1007/s11357-012-9419-5] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 04/20/2012] [Indexed: 05/23/2023]
Abstract
Melatonin and serotonin rhythms, which exhibit a close association with the endogenous circadian component of sleep, are attenuated with increasing age. This decrease seems to be linked to sleep alterations in the elderly. Chrononutrition is a field of chronobiology that establishes the principle of consuming foodstuffs at times of the day when they are more useful for health, improving, therefore, biorhythms and physical performance. Our aim was to analyze whether the consumption of cereals enriched with tryptophan, the precursor of both serotonin and melatonin, may help in the reconsolidation of the sleep/wake cycle and counteract depression and anxiety in 35 middle-aged/elderly (aged 55-75 year) volunteers in a simple blind assay. Data were collected for 3 weeks according to the following schedule: The control week participants consumed standard cereals (22.5 mg tryptophan in 30 g cereals per dose) at breakfast and dinner; for the treatment week, cereals enriched with a higher dose of tryptophan (60 mg tryptophan in 30 g cereals per dose) were eaten at both breakfast and dinner; the posttreatment week volunteers consumed their usual diet. Each participant wore a wrist actimeter that logged activity during the whole experiment. Urine was collected to analyze melatonin and serotonin urinary metabolites and to measure total antioxidant capacity. The consumption of cereals containing the higher dose in tryptophan increased sleep efficiency, actual sleep time, immobile time, and decreased total nocturnal activity, sleep fragmentation index, and sleep latency. Urinary 6-sulfatoxymelatonin, 5-hydroxyindoleacetic acid levels, and urinary total antioxidant capacity also increased respectively after tryptophan-enriched cereal ingestion as well as improving anxiety and depression symptoms. Cereals enriched with tryptophan may be useful as a chrononutrition tool for alterations in the sleep/wake cycle due to age.
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Affiliation(s)
- R Bravo
- Department of Physiology Neuroimmunophysiology and Chrononutrition Research Group, Faculty of Science, University of Extremadura (UEx), Badajoz, Spain.
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11
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Takeuchi K, Yoshii K. Superoxide modifies AMPA receptors and voltage-gated K+ channels of mouse hippocampal neurons. Brain Res 2008; 1236:49-56. [PMID: 18755163 DOI: 10.1016/j.brainres.2008.08.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 08/01/2008] [Accepted: 08/06/2008] [Indexed: 12/25/2022]
Abstract
Lucifer Yellow CH (LY), a fluorescent membrane-impermeable cell-marker dye, has been routinely loaded into cells through recording electrodes to visualize these cells after electrophysiological investigation. Recently we showed that LY produced superoxide when LY was exposed to light at ordinary intensities for microscopy, and that the resultant superoxide retarded the inactivation of voltage-gated Na+ channels even in the dark. Here, we show that superoxide produced by exposure to light prolongs the duration of action potentials, and increases the magnitude of outward rectifier K+ currents and inward rectifier K+ currents in cultured mouse hippocampal neurons. Superoxide also increases the current response of AMPA receptors, but has no effect on that of kainate and NMDA receptors, GABA(A) receptors, high-voltage activated Ca2+ channels of the hippocampal neurons, nor on 5HT3 receptors of N1E-115 cells. These superoxide effects are irreversible. The addition of superoxide dismutase, an enzyme that selectively decomposes superoxide, to LY-loaded recording electrodes reverses the superoxide effects, but addition of heat-inactivated superoxide dismutase fails to reverse the effects. The application of dithiothreitol, a free radical scavenger, to a bathing solution also reverses the superoxide effects. This shows that superoxide rather selectively modifies ion channels. The effects of exogenous and endogenous superoxide on the superoxide-susceptible channels are discussed.
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Affiliation(s)
- Keita Takeuchi
- Graduate school of Life Science and Systems Engineering, Kyushu Institute of Technology, Hibikino 2-4, Kitakyushu-shi 808-0196, Japan
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12
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Pushpalatha K, Nishanth K, Sathyavelu Reddy K. Myocardial antioxidant status and oxidative stress after combined action of exercise training and ethanol in two different age groups of male albino rats. ACTA BIOLOGICA HUNGARICA 2007; 58:173-85. [PMID: 17585507 DOI: 10.1556/abiol.58.2007.2.4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The interaction of exercise training and ethanol on the myocardial antioxidant enzymes and the oxidative stress markers was investigated in the Wistar strain male albino rats. We also tested the interactive effects of exercise training and ethanol on the age-associated free radical production and antioxidant defense system. We found a significant decrease (p<0.05) in the activity levels of superoxide dismutase (SOD) and catalase (CAT) in the myocardium of old rats when compared to young rats by 26% and 58%, respectively, suggesting the onset of age-dependent decrease in the myocardial antioxidant enzyme system. In contrast to the decreased antioxidant enzyme activity, xanthine oxidase (XOD) and lipid peroxidation (LPO) levels were elevated, suggesting the age-induced oxidative stress. Exercise training significantly (p < 0.05) elevated the activities of SOD, CAT, XOD and LPO levels in both the age groups of animals. Ethanol consumption significantly lowered the SOD and CAT activities in both the age groups, whereas a significant increase was observed in the XOD and LPO levels. In contrast, the combination of exercise training plus ethanol lowered XOD and LPO levels in both the age groups of rats compared to ethanol treated rats. A significant (p < 0.05) increase in the activities of SOD and CAT was reported in the rats treated with the combination of exercise training plus ethanol. This increase was more pronounced in the younger rats than the older rats. The findings of the present investigation on the potential role of antioxidant enzymes to counter the ethanol-induced pro-oxidants showed an increase with the interaction of exercise training. With age, a decrease in the antioxidant enzyme capacity was observed. This reveals that the old age rats were more affected to the pro-oxidants when compared to the young age rats. In conclusion it is demonstrated that two months treadmill endurance exercise training is beneficial to both young and old rats in improving antioxidant defense to challenge the oxidative stress in the myocardial tissue and thereby successfully countering the free radical production due to ethanol intoxication.
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Affiliation(s)
- K Pushpalatha
- Department of Zoology, Division of Exercise Physiology, Sri Venkateswara University, Tirupati-517502, A. P., India
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13
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Rosa-Neto P, Benkelfat C, Sakai Y, Leyton M, Morais JA, Diksic M. Brain regional α-[11C]methyl-L-tryptophan trapping, used as an index of 5-HT synthesis, in healthy adults: absence of an age effect. Eur J Nucl Med Mol Imaging 2007; 34:1254-64. [PMID: 17318550 DOI: 10.1007/s00259-007-0365-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2006] [Accepted: 12/26/2006] [Indexed: 01/01/2023]
Abstract
PURPOSE Previous functional neuroimaging studies suggest that selective aspects of the brain serotonin (5-HT) system change during the aging process. Here, we assessed the effects of aging on the brain regional alpha-[(11)C]methyl-L: -tryptophan (alpha-[(11)C]MTrp) trapping rate constant (K*; microl.g(-1).min(-1)), which, with certain assumptions, could be taken as a proxy of 5-HT synthesis. METHODS Thirty-six healthy right-handed subjects had positron emission tomography (PET) scans following injection with alpha-[(11)C]MTrp [18 males aged 46.6 +/- 22.2 years (range 20-80 years) and 18 females aged 33.0 +/- 15.5 years (range 20-80 years)]. The trapping rate constant, K*, was calculated with the graphical method for irreversible ligands using the sinus-venous input function. A priori selected volumes of interest (VOIs) were defined using an automatic algorithm. RESULTS VOI analysis showed no correlation between age and brain regional K* values. As reported by others, significant age-related reductions of gray matter were observed in the thalamus and frontal and cingulate cortices; even with partial volume correction there was still no significant relationship between K* and age. Further exploratory SPM voxelwise correlation between age and alpha-[(11)C]MTrp trapping, using p = 0.05 (uncorrected), as well as voxel-based morphometry, was in agreement with the VOI analysis. CONCLUSION The dissociation between age-related changes in brain anatomy and this index of serotonin synthesis suggests independent mechanisms underlying the normal aging process.
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Affiliation(s)
- Pedro Rosa-Neto
- Department of Neurology and Neurosurgery, McGill University, 3801 University Street, Montreal, Canada
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14
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Stefulj J, Kubat M, Balija M, Jernej B. TPH gene polymorphism and aging: indication of combined effect on the predisposition to violent suicide. Am J Med Genet B Neuropsychiatr Genet 2006; 141B:139-41. [PMID: 16389591 DOI: 10.1002/ajmg.b.30271] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Findings relating serotonin to suicidal behavior suggest the role of genes for tryptophan hydroxylase (TPH) in the genetic substrate of this disorder. Association of Tph1 gene and suicidality, despite considerable research efforts, remains controversial. Polymorphism A218C in intron 7 of Tph1 gene was studied in violent suicide victims (N = 247) and controls (N = 320) of Slavic (Croatian) origin, with specific consideration of the influence of subjects' age. The frequency of, allegedly less active, CC genotype was increased in older (above 65 years) victims as compared to controls (P = 0.0126 and 0.0008, for comparison with age-specific and integral control samples, respectively), while there were no differences between victims under 65 years and controls. Excess of the CC genotype in elderly victims of violent suicide points to the possible combined effect of the respective genetic factor and physiological changes during aging on the predisposition to this disorder.
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Affiliation(s)
- Jasminka Stefulj
- Laboratory of Neurochemistry and Molecular Neurobiology, Rudjer Boskovic Institute, Zagreb, Croatia
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