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Zadeh-Haghighi H, Simon C. Magnetic field effects in biology from the perspective of the radical pair mechanism. J R Soc Interface 2022; 19:20220325. [PMID: 35919980 PMCID: PMC9346374 DOI: 10.1098/rsif.2022.0325] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 07/14/2022] [Indexed: 04/07/2023] Open
Abstract
Hundreds of studies have found that weak magnetic fields can significantly influence various biological systems. However, the underlying mechanisms behind these phenomena remain elusive. Remarkably, the magnetic energies implicated in these effects are much smaller than thermal energies. Here, we review these observations, and we suggest an explanation based on the radical pair mechanism, which involves the quantum dynamics of the electron and nuclear spins of transient radical molecules. While the radical pair mechanism has been studied in detail in the context of avian magnetoreception, the studies reviewed here show that magnetosensitivity is widespread throughout biology. We review magnetic field effects on various physiological functions, discussing static, hypomagnetic and oscillating magnetic fields, as well as isotope effects. We then review the radical pair mechanism as a potential unifying model for the described magnetic field effects, and we discuss plausible candidate molecules for the radical pairs. We review recent studies proposing that the radical pair mechanism provides explanations for isotope effects in xenon anaesthesia and lithium treatment of hyperactivity, magnetic field effects on the circadian clock, and hypomagnetic field effects on neurogenesis and microtubule assembly. We conclude by discussing future lines of investigation in this exciting new area of quantum biology.
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Affiliation(s)
- Hadi Zadeh-Haghighi
- Department of Physics and Astronomy, University of Calgary, Calgary, Alberta, Canada T2N 1N4
- Institute for Quantum Science and Technology, University of Calgary, Calgary, Alberta, Canada T2N 1N4
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada T2N 1N4
| | - Christoph Simon
- Department of Physics and Astronomy, University of Calgary, Calgary, Alberta, Canada T2N 1N4
- Institute for Quantum Science and Technology, University of Calgary, Calgary, Alberta, Canada T2N 1N4
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada T2N 1N4
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2
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Hawrysh PJ, Myrka AM, Buck LT. Review: A history and perspective of mitochondria in the context of anoxia tolerance. Comp Biochem Physiol B Biochem Mol Biol 2022; 260:110733. [PMID: 35288242 DOI: 10.1016/j.cbpb.2022.110733] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 03/07/2022] [Accepted: 03/07/2022] [Indexed: 01/01/2023]
Abstract
Symbiosis is found throughout nature, but perhaps nowhere is it more fundamental than mitochondria in all eukaryotes. Since mitochondria were discovered and mechanisms of oxygen reduction characterized, an understanding gradually emerged that these organelles were involved not just in the combustion of oxygen, but also in the sensing of oxygen. While multiple hypotheses exist to explain the mitochondrial involvement in oxygen sensing, key elements are developing that include potassium channels and reactive oxygen species. To understand how mitochondria contribute to oxygen sensing, it is informative to study a model system which is naturally adapted to survive extended periods without oxygen. Amongst air-breathing vertebrates, the most highly adapted are western painted turtles (Chrysemys picta bellii), which overwinter in ice-covered and anoxic water bodies. Through research of this animal, it was postulated that metabolic rate depression is key to anoxic survival and that mitochondrial regulation is a key aspect. When faced with anoxia, excitatory neurotransmitter receptors in turtle brain are inhibited through mitochondrial calcium release, termed "channel arrest". Simultaneously, inhibitory GABAergic signalling contributes to the "synaptic arrest" of excitatory action potential firing through a pathway dependent on mitochondrial depression of ROS generation. While many pathways are implicated in mitochondrial oxygen sensing in turtles, such as those of adenosine, ATP turnover, and gaseous transmitters, an apparent point of intersection is the mitochondria. In this review we will explore how an organelle that was critical for organismal complexity in an oxygenated world has also become a potentially important oxygen sensor.
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Affiliation(s)
- Peter John Hawrysh
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Alexander Morley Myrka
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Leslie Thomas Buck
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada; Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON M5S 3G5, Canada.
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Akinrinde AS, Fapuro J, Soetan KO. Zinc and ascorbic acid treatment alleviates systemic inflammation and gastrointestinal and renal oxidative stress induced by sodium azide in rats. BENI-SUEF UNIVERSITY JOURNAL OF BASIC AND APPLIED SCIENCES 2021. [DOI: 10.1186/s43088-021-00108-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Sodium azide (NaN3) is a chemical of rapidly increasing economic importance but with high toxic attributes. In this study, the effects of zinc (Zn) and ascorbic acid (AsA) supplementation on sodium azide (NaN3)-induced toxicity in the stomach, colon and kidneys were evaluated in Wistar rats. Twenty-eight rats were randomly allocated to four experimental groups as follows: group A (control) given distilled water only; group B (NaN3 only, 20 mg/kg); group C (NaN3 + zinc sulphate, ZnSO4 80 mg/kg); and group D (NaN3 + AsA 200 mg/kg).
Results
NaN3 was found to significantly (p < 0.05) induce increases in serum nitric oxide (NO), advanced oxidation protein products (AOPP), myeloperoxidase (MPO) and total protein levels, along with significant (p < 0.05) increase in gastric, colonic and renal malondialdehyde (MDA) and protein carbonyl (PCO) levels. In addition, NaN3 induced significant (p < 0.05) reduction in superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione S-transferase (GST) activities in the colon and kidneys. Treatment with Zn or AsA caused significant (p < 0.05) reduction in serum levels of oxidative and inflammatory markers, as well as tissue PCO and MDA levels. Moreover, co-treatment with Zn or AsA significantly (p < 0.05) restored colonic and renal levels of antioxidant enzymes, reduced glutathione and protein thiols.
Conclusions
This study shows that Zn or AsA supplementation alleviated NaN3 toxicity by suppressing systemic inflammation and preventing oxidative damage in the stomach, colon and kidneys of rats.
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Country MW, Jonz MG. Mitochondrial KATP channels stabilize intracellular Ca2+ during hypoxia in retinal horizontal cells of goldfish (Carassius auratus). J Exp Biol 2021; 224:271844. [PMID: 34402511 DOI: 10.1242/jeb.242634] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 08/11/2021] [Indexed: 01/20/2023]
Abstract
Neurons of the retina require oxygen to survive. In hypoxia, neuronal ATP production is impaired, ATP-dependent ion pumping is reduced, transmembrane ion gradients are dysregulated, and intracellular Ca2+ concentration ([Ca2+]i) increases enough to trigger excitotoxic cell death. Central neurons of the common goldfish (Carassius auratus) are hypoxia tolerant, but little is known about how goldfish retinas withstand hypoxia. To study the cellular mechanisms of hypoxia tolerance, we isolated retinal interneurons (horizontal cells; HCs), and measured [Ca2+]i with Fura-2. Goldfish HCs maintained [Ca2+]i throughout 1 h of hypoxia, whereas [Ca2+]i increased irreversibly in HCs of the hypoxia-sensitive rainbow trout (Oncorhynchus mykiss) with just 20 min of hypoxia. Our results suggest mitochondrial ATP-dependent K+ channels (mKATP) are necessary to stabilize [Ca2+]i throughout hypoxia. In goldfish HCs, [Ca2+]i increased when mKATP channels were blocked with glibenclamide or 5-hydroxydecanoic acid, whereas the mKATP channel agonist diazoxide prevented [Ca2+]i from increasing in hypoxia in trout HCs. We found that hypoxia protects against increases in [Ca2+]i in goldfish HCs via mKATP channels. Glycolytic inhibition with 2-deoxyglucose increased [Ca2+]i, which was rescued by hypoxia in a mKATP channel-dependent manner. We found no evidence of plasmalemmal KATP channels in patch-clamp experiments. Instead, we confirmed the involvement of KATP in mitochondria with TMRE imaging, as hypoxia rapidly (<5 min) depolarized mitochondria in a mKATP channel-sensitive manner. We conclude that mKATP channels initiate a neuroprotective pathway in goldfish HCs to maintain [Ca2+]i and avoid excitotoxicity in hypoxia. This model provides novel insight into the cellular mechanisms of hypoxia tolerance in the retina.
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Affiliation(s)
- Michael W Country
- Department of Biology, University of Ottawa, Ottawa, ON, CanadaK1N 6N5
| | - Michael G Jonz
- Department of Biology, University of Ottawa, Ottawa, ON, CanadaK1N 6N5.,Brain and Mind Research Institute, University of Ottawa, Ottawa, ON, CanadaK1H 8M5
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5
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Myrka A, Buck L. Cytoskeletal Arrest: An Anoxia Tolerance Mechanism. Metabolites 2021; 11:metabo11080561. [PMID: 34436502 PMCID: PMC8401981 DOI: 10.3390/metabo11080561] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/13/2021] [Accepted: 08/14/2021] [Indexed: 12/16/2022] Open
Abstract
Polymerization of actin filaments and microtubules constitutes a ubiquitous demand for cellular adenosine-5′-triphosphate (ATP) and guanosine-5′-triphosphate (GTP). In anoxia-tolerant animals, ATP consumption is minimized during overwintering conditions, but little is known about the role of cell structure in anoxia tolerance. Studies of overwintering mammals have revealed that microtubule stability in neurites is reduced at low temperature, resulting in withdrawal of neurites and reduced abundance of excitatory synapses. Literature for turtles is consistent with a similar downregulation of peripheral cytoskeletal activity in brain and liver during anoxic overwintering. Downregulation of actin dynamics, as well as modification to microtubule organization, may play vital roles in facilitating anoxia tolerance. Mitochondrial calcium release occurs during anoxia in turtle neurons, and subsequent activation of calcium-binding proteins likely regulates cytoskeletal stability. Production of reactive oxygen species (ROS) formation can lead to catastrophic cytoskeletal damage during overwintering and ROS production can be regulated by the dynamics of mitochondrial interconnectivity. Therefore, suppression of ROS formation is likely an important aspect of cytoskeletal arrest. Furthermore, gasotransmitters can regulate ROS levels, as well as cytoskeletal contractility and rearrangement. In this review we will explore the energetic costs of cytoskeletal activity, the cellular mechanisms regulating it, and the potential for cytoskeletal arrest being an important mechanism permitting long-term anoxia survival in anoxia-tolerant species, such as the western painted turtle and goldfish.
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Affiliation(s)
- Alexander Myrka
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada;
| | - Leslie Buck
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada;
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
- Correspondence: ; Tel.: +1-416-978-3506
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Pillai V, Buck L, Lari E. Scavenging of reactive oxygen species mimics the anoxic response in goldfish pyramidal neurons. J Exp Biol 2021; 224:268949. [PMID: 34047778 DOI: 10.1242/jeb.238147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 04/20/2021] [Indexed: 12/11/2022]
Abstract
Goldfish are one of a few species able to avoid cellular damage during month-long periods in severely hypoxic environments. By suppressing action potentials in excitatory glutamatergic neurons, the goldfish brain decreases its overall energy expenditure. Coincident with reductions in O2 availability is a natural decrease in cellular reactive oxygen species (ROS) generation, which has been proposed to function as part of a low-oxygen signal transduction pathway. Using live-tissue fluorescence microscopy, we found that ROS production decreased by 10% with the onset of anoxia in goldfish telencephalic brain slices. Employing whole-cell patch-clamp recording, we found that, similar to severe hypoxia, the ROS scavengers N-acetyl cysteine (NAC) and MitoTEMPO, added during normoxic periods, depolarized membrane potential (severe hypoxia -73.6 to -61.4 mV, NAC -76.6 to -66.2 mV and MitoTEMPO -71.5 mV to -62.5 mV) and increased whole-cell conductance (severe hypoxia 5.7 nS to 8.0 nS, NAC 6.0 nS to 7.5 nS and MitoTEMPO 6.0 nS to 7.6 nS). Also, in a subset of active pyramidal neurons, these treatments reduced action potential firing frequency (severe hypoxia 0.18 Hz to 0.03 Hz, NAC 0.27 Hz to 0.06 Hz and MitoTEMPO 0.35 Hz to 0.08 Hz). Neither severe hypoxia nor ROS scavenging impacted action potential threshold. The addition of exogenous hydrogen peroxide could reverse the effects of the antioxidants. Taken together, this supports a role for a reduction in [ROS] as a low-oxygen signal in goldfish brain.
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Affiliation(s)
- Varshinie Pillai
- Department of Cell & Systems Biology, University of Toronto, Toronto, ON, Canada, M3A 3A7
| | - Leslie Buck
- Department of Cell & Systems Biology, University of Toronto, Toronto, ON, Canada, M3A 3A7
| | - Ebrahim Lari
- Department of Cell & Systems Biology, University of Toronto, Toronto, ON, Canada, M3A 3A7
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7
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Morris G, Walker AJ, Walder K, Berk M, Marx W, Carvalho AF, Maes M, Puri BK. Increasing Nrf2 Activity as a Treatment Approach in Neuropsychiatry. Mol Neurobiol 2021; 58:2158-2182. [PMID: 33411248 DOI: 10.1007/s12035-020-02212-w] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 11/16/2020] [Indexed: 02/07/2023]
Abstract
Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor encoded by NFE2L2. Under oxidative stress, Nrf2 does not undergo its normal cytoplasmic degradation but instead travels to the nucleus, where it binds to a DNA promoter and initiates transcription of anti-oxidative genes. Nrf2 upregulation is associated with increased cellular levels of glutathione disulfide, glutathione peroxidase, glutathione transferases, thioredoxin and thioredoxin reductase. Given its key role in governing the cellular antioxidant response, upregulation of Nrf2 has been suggested as a common therapeutic target in neuropsychiatric illnesses such as major depressive disorder, bipolar disorder and schizophrenia, which are associated with chronic oxidative and nitrosative stress, characterised by elevated levels of reactive oxygen species, nitric oxide and peroxynitrite. These processes lead to extensive lipid peroxidation, protein oxidation and carbonylation, and oxidative damage to nuclear and mitochondrial DNA. Intake of N-acetylcysteine, coenzyme Q10 and melatonin is accompanied by increased Nrf2 activity. N-acetylcysteine intake is associated with improved cerebral mitochondrial function, decreased central oxidative and nitrosative stress, reduced neuroinflammation, alleviation of endoplasmic reticular stress and suppression of the unfolded protein response. Coenzyme Q10, which acts as a superoxide scavenger in neuroglial mitochondria, instigates mitohormesis, ameliorates lipid peroxidation in the inner mitochondrial membrane, activates uncoupling proteins, promotes mitochondrial biogenesis and has positive effects on the plasma membrane redox system. Melatonin, which scavenges mitochondrial free radicals, inhibits mitochondrial nitric oxide synthase, restores mitochondrial calcium homeostasis, deacetylates and activates mitochondrial SIRT3, ameliorates increased permeability of the blood-brain barrier and intestine and counters neuroinflammation and glutamate excitotoxicity.
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Affiliation(s)
- G Morris
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Barwon Health, School of Medicine, Deakin University, Geelong, VIC, Australia
| | - A J Walker
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Barwon Health, School of Medicine, Deakin University, Geelong, VIC, Australia
| | - K Walder
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Barwon Health, School of Medicine, Deakin University, Geelong, VIC, Australia
| | - M Berk
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Barwon Health, School of Medicine, Deakin University, Geelong, VIC, Australia.,CMMR Strategic Research Centre, School of Medicine, Deakin University, Geelong, VIC, Australia.,Orygen, The National Centre of Excellence in Youth Mental Health, The Department of Psychiatry and the Florey Institute for Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
| | - W Marx
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Barwon Health, School of Medicine, Deakin University, Geelong, VIC, Australia
| | - A F Carvalho
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada.,Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
| | - M Maes
- Institute for Mental and Physical Health and Clinical Translation (IMPACT), Barwon Health, School of Medicine, Deakin University, Geelong, VIC, Australia.,Department of Psychiatry, Chulalongkorn University, Bangkok, Thailand
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Hossein-Javaheri N, Buck LT. GABA receptor inhibition and severe hypoxia induce a paroxysmal depolarization shift in goldfish neurons. J Neurophysiol 2020; 125:321-330. [PMID: 33296606 DOI: 10.1152/jn.00149.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Mammalian neurons undergo rapid excitotoxic cell death when deprived of oxygen; however, the common goldfish (Carassius auratus) has the unique ability of surviving in oxygen-free waters, under anoxia. This organism utilizes γ-amino butyric acid (GABA) signaling to suppress excitatory glutamatergic activity during anoxic periods. Although GABAA receptor antagonists are not deleterious to the cellular survival, coinhibition of GABAA and GABAB receptors is detrimental by abolishing anoxia-induced neuroprotective mechanisms. Here we show that blocking the anoxic GABAergic neurotransmission induces seizure-like activity (SLA) analogous to a paroxysmal depolarization shift (PDS), with hyperpolarization of action potential (AP) threshold and elevation of threshold currents. The observed PDS was attributed to an increase in excitatory postsynaptic currents (EPSCs) that are normally attenuated with decreasing oxygen levels. Furthermore, for the first time, we show that in addition to PDS, some neurons undergo depolarization block and do not generate AP despite a suprathreshold membrane potential. In conclusion, our results indicate that with severe hypoxia and absence of GABA receptor activity, telencephalic neurons of C. auratus manifest a paroxysmal depolarization shift, a key feature of epileptic discharge.NEW & NOTEWORTHY This work shows that the combination of anoxia and inhibition of GABA receptors induces seizure-like activities in goldfish telencephalic pyramidal and stellate neurons. Importantly, to prevent seizure-like activity, an intact GABA-mediated inhibitory pathway is required.
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Affiliation(s)
| | - Leslie Thomas Buck
- Department of Cell & Systems Biology, University of Toronto, Toronto, Ontario, Canada
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9
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Savyuk M, Krivonosov M, Mishchenko T, Gazaryan I, Ivanchenko M, Khristichenko A, Poloznikov A, Hushpulian D, Nikulin S, Tonevitsky E, Abuzarova G, Mitroshina E, Vedunova M. Neuroprotective Effect of HIF Prolyl Hydroxylase Inhibition in an In Vitro Hypoxia Model. Antioxidants (Basel) 2020; 9:E662. [PMID: 32722310 PMCID: PMC7463909 DOI: 10.3390/antiox9080662] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/17/2020] [Accepted: 07/20/2020] [Indexed: 01/19/2023] Open
Abstract
A novel potent analog of the branched tail oxyquinoline group of hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitors, neuradapt, has been studied in two treatment regimes in an in vitro hypoxia model on murine primary hippocampal cultures. Neuradapt activates the expression of HIF1 and HIF2 target genes and shows no toxicity up to 20 μM, which is more than an order of magnitude higher than its biologically active concentration. Cell viability, functional activity, and network connectivity between the elements of neuronal networks have been studied using a pairwise correlation analysis of the intracellular calcium fluctuations in the individual cells. An immediate treatment with 1 μМ and 15 μМ neuradapt right at the onset of hypoxia not only protects from the death, but also maintains the spontaneous calcium activity in nervous cells at the level of the intact cultures. A similar neuroprotective effect in the post-treatment scenario is observed for 15 μМ, but not for 1 μМ neuradapt. Network connectivity is better preserved with immediate treatment using 1 μМ neuradapt than with 15 μМ, which is still beneficial. Post-treatment with neuradapt did not restore the network connectivity despite the observation that neuradapt significantly increased cell viability at 1 μМ and functional activity at 15 μМ. The preservation of cell viability and functional activity makes neuradapt promising for further studies in a post-treatment scenario, since it can be combined with other drugs and treatments restoring the network connectivity of functionally competent cells.
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Affiliation(s)
- Maria Savyuk
- Department of Neurotechnology, Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Ave., Nizhny Novgorod 603950, Russia; (M.S.); (T.M.); (E.M.)
| | - Mikhail Krivonosov
- Department of Applied Mathematics, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Ave., Nizhny Novgorod 603950, Russia; (M.K.); (M.I.)
| | - Tatiana Mishchenko
- Department of Neurotechnology, Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Ave., Nizhny Novgorod 603950, Russia; (M.S.); (T.M.); (E.M.)
| | - Irina Gazaryan
- P. A. Hertsen Moscow Oncology Research Center, Branch of the National Medical Research Radiological Center, Ministry of Health of the Russian Federation, Moscow 125284, Russia; (I.G.); (A.K.); or (A.P.); (D.H.); (G.A.)
- Chemical Enzymology Department, Chemistry Faculty, M. V. Lomonosov Moscow State University, Moscow 119992, Russia
| | - Mikhail Ivanchenko
- Department of Applied Mathematics, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Ave., Nizhny Novgorod 603950, Russia; (M.K.); (M.I.)
| | - Anna Khristichenko
- P. A. Hertsen Moscow Oncology Research Center, Branch of the National Medical Research Radiological Center, Ministry of Health of the Russian Federation, Moscow 125284, Russia; (I.G.); (A.K.); or (A.P.); (D.H.); (G.A.)
| | - Andrey Poloznikov
- P. A. Hertsen Moscow Oncology Research Center, Branch of the National Medical Research Radiological Center, Ministry of Health of the Russian Federation, Moscow 125284, Russia; (I.G.); (A.K.); or (A.P.); (D.H.); (G.A.)
- Faculty of Biology and Biotechnologies, Higher School of Economics, Moscow 101000, Russia;
| | - Dmitry Hushpulian
- P. A. Hertsen Moscow Oncology Research Center, Branch of the National Medical Research Radiological Center, Ministry of Health of the Russian Federation, Moscow 125284, Russia; (I.G.); (A.K.); or (A.P.); (D.H.); (G.A.)
- School of Biomedicine, Far Eastern Federal University, Vladivostok 690091, Russia
| | - Sergey Nikulin
- Faculty of Biology and Biotechnologies, Higher School of Economics, Moscow 101000, Russia;
| | - Evgeny Tonevitsky
- Development Fund of the Innovation Science and Technology Center “Mendeleev Valley”, Moscow 125480, Russia;
| | - Guzal Abuzarova
- P. A. Hertsen Moscow Oncology Research Center, Branch of the National Medical Research Radiological Center, Ministry of Health of the Russian Federation, Moscow 125284, Russia; (I.G.); (A.K.); or (A.P.); (D.H.); (G.A.)
| | - Elena Mitroshina
- Department of Neurotechnology, Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Ave., Nizhny Novgorod 603950, Russia; (M.S.); (T.M.); (E.M.)
| | - Maria Vedunova
- Department of Neurotechnology, Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Ave., Nizhny Novgorod 603950, Russia; (M.S.); (T.M.); (E.M.)
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Bundgaard A, Ruhr IM, Fago A, Galli GL. Metabolic adaptations to anoxia and reoxygenation: New lessons from freshwater turtles and crucian carp. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/j.coemr.2020.01.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Nakazawa K, Sapkota K. The origin of NMDA receptor hypofunction in schizophrenia. Pharmacol Ther 2019; 205:107426. [PMID: 31629007 DOI: 10.1016/j.pharmthera.2019.107426] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 10/10/2019] [Indexed: 12/12/2022]
Abstract
N-methyl-d-aspartate (NMDA) receptor (NMDAR) hypofunction plays a key role in pathophysiology of schizophrenia. Since NMDAR hypofunction has also been reported in autism, Alzheimer's disease and cognitive dementia, it is crucial to identify the location, timing, and mechanism of NMDAR hypofunction for schizophrenia for better understanding of disease etiology and for novel therapeutic intervention. In this review, we first discuss the shared underlying mechanisms of NMDAR hypofunction in NMDAR antagonist models and the anti-NMDAR autoantibody model of schizophrenia and suggest that NMDAR hypofunction could occur in GABAergic neurons in both models. Preclinical models using transgenic mice have shown that NMDAR hypofunction in cortical GABAergic neurons, in particular parvalbumin-positive fast-spiking interneurons, in the early postnatal period confers schizophrenia-related phenotypes. Recent studies suggest that NMDAR hypofunction can also occur in PV-positive GABAergic neurons with alterations of NMDAR-associated proteins, such as neuregulin/ErbB4, α7nAChR, and serine racemase. Furthermore, several environmental factors, such as oxidative stress, kynurenic acid and hypoxia, may also potentially elicit NMDAR hypofunction in GABAergic neurons in early postnatal period. Altogether, the studies discussed here support a central role for GABAergic abnormalities in the context of NMDAR hypofunction. We conclude by suggesting potential therapeutic strategies to improve the function of fast-spiking neurons.
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The hypoxia-tolerant vertebrate brain: Arresting synaptic activity. Comp Biochem Physiol B Biochem Mol Biol 2018; 224:61-70. [DOI: 10.1016/j.cbpb.2017.11.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/23/2017] [Accepted: 11/30/2017] [Indexed: 01/16/2023]
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Ameliorative effect of vitamin E and selenium against oxidative stress induced by sodium azide in liver, kidney, testis and heart of male mice. Biomed Pharmacother 2017; 91:602-610. [PMID: 28494416 DOI: 10.1016/j.biopha.2017.04.122] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 04/18/2017] [Accepted: 04/27/2017] [Indexed: 01/26/2023] Open
Abstract
The study purported to define the effects of daily administration of vitamin E (Vit E) and selenium (Se) on antioxidant enzyme activity in mice treated with high doses of sodium azide (SA). Male mice were randomly split into nine groups. Groups 1, 2 and 3 were injected daily with saline, Vit E, and Se, respectively, while groups 4, 5 and 6 administrated with different doses of SA (low, medium and high, respectively). The mice in groups 7, 8 and 9 received 100mg/kg Vit E, 17.5mg/kg Se, and a combination of Vit E and Se, respectively before the SA-treatment. Hepatic, renal, testis and heart, antioxidant enzymes as well as levels of lipid peroxidation and total antioxidant capacity levels were determined. Vit E alone affected on the antioxidant parameters of the examined tissues. Se had a preventive effect on the decrease of antioxidant parameters caused by SA and improved the diminished activities of all of them. The study demonstrates that a high dose of SA may alter the effects of normal level antioxidant/oxidative status of male mice and that Se is effective in reducing the SA-damage. Se acts as a synergistic agent with the effect of Vit E in various damaged caused by SA.
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14
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Phosphorylation of the mitochondrial ATP-sensitive potassium channel occurs independently of PKCε in turtle brain. Comp Biochem Physiol B Biochem Mol Biol 2016; 200:44-53. [DOI: 10.1016/j.cbpb.2016.06.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 05/26/2016] [Accepted: 06/01/2016] [Indexed: 01/25/2023]
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Abstract
Many environmental conditions can constrain the ability of animals to obtain sufficient food energy, or transform that food energy into useful chemical forms. To survive extended periods under such conditions animals must suppress metabolic rate to conserve energy, water, or oxygen. Amongst small endotherms, this metabolic suppression is accompanied by and, in some cases, facilitated by a decrease in core body temperature-hibernation or daily torpor-though significant metabolic suppression can be achieved even with only modest cooling. Within some ectotherms, winter metabolic suppression exceeds the passive effects of cooling. During dry seasons, estivating ectotherms can reduce metabolism without changes in body temperature, conserving energy reserves, and reducing gas exchange and its inevitable loss of water vapor. This overview explores the similarities and differences of metabolic suppression among these states within adult animals (excluding developmental diapause), and integrates levels of organization from the whole animal to the genome, where possible. Several similarities among these states are highlighted, including patterns and regulation of metabolic balance, fuel use, and mitochondrial metabolism. Differences among models are also apparent, particularly in whether the metabolic suppression is intrinsic to the tissue or depends on the whole-animal response. While in these hypometabolic states, tissues from many animals are tolerant of hypoxia/anoxia, ischemia/reperfusion, and disuse. These natural models may, therefore, serve as valuable and instructive models for biomedical research.
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Affiliation(s)
- James F Staples
- Department of Biology, University of Western Ontario, London, Ontario, Canada
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16
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Olajide OJ, Enaibe BU, Bankole OO, Akinola OB, Laoye BJ, Ogundele OM. Kolaviron was protective against sodium azide (NaN3) induced oxidative stress in the prefrontal cortex. Metab Brain Dis 2016; 31:25-35. [PMID: 25916484 DOI: 10.1007/s11011-015-9674-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 04/20/2015] [Indexed: 12/19/2022]
Abstract
Kolaviron is a phytochemical isolated from Garcina kola (G. kola); a common oral masticatory agent in Nigeria (West Africa). It is a bioflavonoid used--as an antiviral, anti-inflammatory and antioxidant--in relieving the symptoms of several diseases and infections. In this study we have evaluated the neuroprotective and regenerative effect of kolaviron in neurons of the prefrontal cortex (Pfc) before or after exposure to sodium azide (NaN3) induced oxidative stress. Separate groups of animals were treated as follows; kolaviron (200 mg/Kg) for 21 days; kolaviron (200 mg/Kg for 21 days) followed by NaN3 treatment (20 mg/Kg for 5 days); NaN3 treatment (20 mg/Kg for 5 days) followed by kolaviron (200 mg/Kg for 21 days); 1 ml of corn-oil (21 days-vehicle); NaN3 treatment (20 mg/Kg for 5 days). Exploratory activity associated with Pfc function was assessed in the open field test (OFT) following which the microscopic anatomy of the prefrontal cortex was examined in histology (Haematoxylin and Eosin) and antigen retrieval Immunohistochemistry to show astroglia activation (GFAP), neuronal metabolism (NSE), cytoskeleton (NF) and cell cycle dysregulation (p53). Subsequently, we quantified the level of Glucose-6-phosphate dehydrogenase (G6PDH) and lactate dehydrogenase (LDH) in the brain tissue homogenate as a measure of stress-related glucose metabolism. Kolaviron (Kv) and Kolaviron/NaN3 treatment caused no prominent change in astroglia density and size while NaN3 and NaN3/Kv induced astroglia activation and scar formation (astrogliosis) in the Pfc when compared with the control. Similarly, Kolaviron and Kv/NaN3 did not alter NSE expression (glucose metabolism) while NaN3 and NaN3/Kv treatment increased cortical NSE expression; thus indicating stress related metabolism. Further studies on enzymes of glucose metabolism (G6PDH and LDH) showed that NaN3 increased LDH while kolaviron reduced LDH in the brain tissue homogenate (P < 0.001). In addition kolaviron treatment before (P < 0.001) or after (P < 0.05) NaN3 treatment also reduced LDH expression; thus supporting its role in suppression of oxidative stress. Interestingly, NF deposition increased in the Pfc after kolaviron treatment while Kv/NaN3 showed no significant change in NF when compared with the control. In furtherance, NaN3 and NaN3/Kv caused a decrease in NF deposition (degeneration). Ultimately, the protective effect of KV administered prior to NaN3 treatment was confirmed through p53 expression; which was similar to the control. However, NaN3 and NaN3/Kv caused an increase in p53 expression in the Pfc neurons (cell cycle dysregulation). We conclude that kolaviron is not neurotoxic when used at 200 mg/Kg BW. Furthermore, 200 mg/Kg of kolaviron administered prior to NaN3 treatment (Kv/NaN3) was neuroprotective when compared with Kolaviron administered after NaN3 treatment (NaN3/Kv). Some of the observed effects of kolaviron administered before NaN3 treatment includes reduction of astroglia activation, absence of astroglia scars, antioxidation (reduced NSE and LDH), prevention of neurofilament loss and cell cycle regulation.
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Affiliation(s)
- Olayemi J Olajide
- Department of Anatomy, College of Health Sciences, University of Ilorin, Ilorin, Kwara State, Nigeria
| | - Bernard U Enaibe
- Department of Anatomy, College of Health Sciences, University of Ilorin, Ilorin, Kwara State, Nigeria
| | - Oluwamolakun O Bankole
- Neurobiology Unit; Department of Biological Sciences, College of Sciences, Afe Babalola University, Ado-Ekiti, Ekiti State, Nigeria
| | - Oluwole B Akinola
- Department of Anatomy, College of Health Sciences, University of Ilorin, Ilorin, Kwara State, Nigeria
| | - Babafemi J Laoye
- Neurobiology Unit; Department of Biological Sciences, College of Sciences, Afe Babalola University, Ado-Ekiti, Ekiti State, Nigeria
| | - Olalekan M Ogundele
- Neural Systems Unit; Department of Anatomy, College of Medicine and Health Sciences, Afe Babalola University, College Building II, 2nd Floor, Room G14, Km 8.5 Afe Babalola Way, Ado-Ekiti, Ekiti State, Nigeria.
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17
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Nagano T, Mizuno M, Morita K, Nawa H. Pathological Implications of Oxidative Stress in Patients and Animal Models with Schizophrenia: The Role of Epidermal Growth Factor Receptor Signaling. Curr Top Behav Neurosci 2016; 29:429-446. [PMID: 26475158 DOI: 10.1007/7854_2015_399] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Proinflammatory cytokines perturb brain development and neurotransmission and are implicated in various psychiatric diseases, such as schizophrenia and depression. These cytokines often induce the production of reactive oxygen species (ROS) and regulate not only cell survival and proliferation but also inflammatory process and neurotransmission. Under physiological conditions, ROS are moderately produced in mitochondria but are rapidly scavenged by reducing agents in cells. However, brain injury, ischemia, infection, or seizure-like neural activities induce inflammatory cytokines and trigger the production of excessive amounts of ROS, leading to abnormal brain functions and psychiatric symptoms. Protein phosphatases, which are involved in the basal silencing of cytokine receptor activation, are the major targets of ROS. Consistent with this, several ROS scavengers, such as polyphenols and unsaturated fatty acids, attenuate both cytokine signaling and psychiatric abnormalities. In this review, we list the inducers, producers, targets, and scavengers of ROS in the brain and discuss the interaction between ROS and cytokine signaling implicated in schizophrenia and its animal models. In particular, we present an animal model of schizophrenia established by perinatal exposure to epidermal growth factor and illustrate the pathological role of ROS and antipsychotic actions of ROS scavengers, such as emodin and edaravone.
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Affiliation(s)
- Tadasato Nagano
- Faculty of Human Life Studies, University of Niigata Prefecture, 471 Ebigase, Higashi-ku, Niigata, 950-8680, Japan
| | - Makoto Mizuno
- Aichi Human Service Center, Institute for Developmental Research, Kasugai, Aichi, 480-0392, Japan
| | - Keisuke Morita
- Department of Molecular Biology, Brain Research Institute, Niigata University, Asahimachi-Dori 1-757, Niigata, 951-8585, Japan
| | - Hiroyuki Nawa
- Department of Molecular Biology, Brain Research Institute, Niigata University, Asahimachi-Dori 1-757, Niigata, 951-8585, Japan.
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18
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Hossein-Javaheri N, Wilkie MP, Lado WE, Buck LT. Stellate and pyramidal neurons in goldfish telencephalon respond differently to anoxia and GABA receptor inhibition. J Exp Biol 2016; 220:695-704. [DOI: 10.1242/jeb.146605] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 11/30/2016] [Indexed: 01/13/2023]
Abstract
With oxygen deprivation, the mammalian brain undergoes hyper-activity and neuronal death while this does not occur in the anoxia tolerant goldfish (Carassius auratus). Anoxic survival of the goldfish may rely on neuromodulatory mechanisms to suppress neuronal hyper-excitability. Since γ-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in brain, we decided to investigate its potential role in suppressing the electrical activity of goldfish telencephalic neurons. Utilizing whole-cell patch-clamp recording we recorded the electrical activities of both excitatory (pyramidal) and inhibitory (stellate) neurons. With anoxia, membrane potential (Vm) depolarized in both cell types from −72.2mV to −57.7mV and from −64.5mV to −46.8mV in pyramidal and stellate neurons, respectively. While pyramidal cells remained mostly quiescent, action potential frequency (APf) of the stellate neurons increased 68 fold. Furthermore, the GABAA receptor reversal potential (EGABA) was determined using the gramicidin perforated-patch clamp method and found to be depolarizing in pyramidal (−53.8mV) and stellate neurons (−42.1mV). Although GABA was depolarizing, pyramidal neurons remained quiescent since EGABA is below the action potential threshold (−36mV pyramidal and −38mV stellate neurons). Inhibition of GABAA receptors with gabazine reversed the anoxia mediated response. While GABAB receptor inhibition alone did not affect the anoxic response, co-antagonism of GABAA and GABAB receptors (gabazine and CGP-55848) lead to generation of seizure-like activities in both neuron types. We conclude that with anoxia Vm depolarizes towards EGABA which increases APf in stellate neurons and decreases APf in pyramidal neurons, and that GABA plays an important role in the anoxia-tolerance of goldfish brain.
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Affiliation(s)
- Nariman Hossein-Javaheri
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord St, Toronto, ON, M5S 3G5, USA
| | - Michael P. Wilkie
- Department of Biology, Wilfred Laurier University, 75 University Avenue West, Waterloo, ON, N2L 3C5, USA
| | - Wudu E. Lado
- Department of Neurobiology, University of Alabama at Birmingham, 1825 University Blvd, Birmingham, AL, 35294-2182, USA
| | - Leslie T. Buck
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord St, Toronto, ON, M5S 3G5, USA
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19
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Kumar A. NMDA Receptor Function During Senescence: Implication on Cognitive Performance. Front Neurosci 2015; 9:473. [PMID: 26732087 PMCID: PMC4679982 DOI: 10.3389/fnins.2015.00473] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Accepted: 11/25/2015] [Indexed: 12/13/2022] Open
Abstract
N-methyl-D-aspartate (NMDA) receptors, a family of L-glutamate receptors, play an important role in learning and memory, and are critical for spatial memory. These receptors are tetrameric ion channels composed of a family of related subunits. One of the hallmarks of the aging human population is a decline in cognitive function; studies in the past couple of years have demonstrated deterioration in NMDA receptor subunit expression and function with advancing age. However, a direct relationship between impaired memory function and a decline in NMDA receptors is still ambiguous. Recent studies indicate a link between an age-associated NMDA receptor hypofunction and memory impairment and provide evidence that age-associated enhanced oxidative stress might be contributing to the alterations associated with senescence. However, clear evidence is still deficient in demonstrating the underlying mechanisms and a relationship between age-associated impaired cognitive faculties and NMDA receptor hypofunction. The current review intends to present an overview of the research findings regarding changes in expression of various NMDA receptor subunits and deficits in NMDA receptor function during senescence and its implication in age-associated impaired hippocampal-dependent memory function.
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Affiliation(s)
- Ashok Kumar
- Department of Neuroscience, Evelyn F. and William L. McKnight Brain Institute, University of Florida Gainesville, FL, USA
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20
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Turtle anoxia tolerance: Biochemistry and gene regulation. Biochim Biophys Acta Gen Subj 2015; 1850:1188-96. [DOI: 10.1016/j.bbagen.2015.02.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Accepted: 02/01/2015] [Indexed: 12/16/2022]
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21
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TrkB-Mediated Neuroprotective and Antihypoxic Properties of Brain-Derived Neurotrophic Factor. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:453901. [PMID: 26075035 PMCID: PMC4444591 DOI: 10.1155/2015/453901] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 04/15/2015] [Accepted: 04/15/2015] [Indexed: 11/18/2022]
Abstract
The neuroprotective and antihypoxic effects of brain-derived neurotrophic factor (BDNF) on dissociated hippocampal cultures in a hypoxia model were investigated. These experiments demonstrate that 10 minutes of normobaric hypoxia increased the number of dead cells in primary culture, whereas a preventive application of BDNF increased the number of viable cells. Spontaneous bioelectrical and calcium activity in neural networks was analyzed using multielectrode arrays and functional intravital calcium imaging. The results indicate that BDNF affects the functional parameters of neuronal networks in dissociated hippocampal cultures over the 7-day posthypoxic period. In addition, the effects of k252a, an antagonist of tropomyosin-related kinase B (TrkB), on functional bioelectrical activity during and after acute hypoxia were investigated. It was shown that the protective effects of BDNF are associated with binding to the TrkB receptor. Finally, intravital fluorescent mRNA probes were used to study the role of NF-κB1 in the protective effects of BDNF. Our experiments revealed that BDNF application stimulates NF-κB1 mRNA synthesis in primary dissociated hippocampal cells under normal conditions but not in hypoxic state.
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22
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Hogg DW, Pamenter ME, Dukoff DJ, Buck LT. Decreases in mitochondrial reactive oxygen species initiate GABA(A) receptor-mediated electrical suppression in anoxia-tolerant turtle neurons. J Physiol 2015; 593:2311-26. [PMID: 25781154 DOI: 10.1113/jp270474] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 03/12/2015] [Indexed: 12/16/2022] Open
Abstract
Anoxia induces hyper-excitability and cell death in mammalian brain but in the anoxia-tolerant western painted turtle (Chrysemys picta bellii) neuronal electrical activity is suppressed (i.e. spike arrest), adenosine triphosphate (ATP) consumption is reduced, and cell death does not occur. Electrical suppression is primarily the result of enhanced γ-aminobutyric acid (GABA) transmission; however, the underlying mechanism responsible for initiating oxygen-sensitive GABAergic spike arrest is unknown. In turtle cortical pyramidal neurons there are three types of GABA(A) receptor-mediated currents: spontaneous inhibitory postsynaptic currents (IPSCs), giant IPSCs and tonic currents. The aim of this study was to assess the effects of reactive oxygen species (ROS) scavenging on these three currents since ROS levels naturally decrease with anoxia and may serve as a redox signal to initiate spike arrest. We found that anoxia, pharmacological ROS scavenging, or inhibition of mitochondrial ROS generation enhanced all three types of GABA currents, with tonic currents comprising ∼50% of the total current. Application of hydrogen peroxide inhibited all three GABA currents, demonstrating a reversible redox-sensitive signalling mechanism. We conclude that anoxia-mediated decreases in mitochondrial ROS production are sufficient to initiate a redox-sensitive inhibitory GABA signalling cascade that suppresses electrical activity when oxygen is limited. This unique strategy for reducing neuronal ATP consumption during anoxia represents a natural mechanism in which to explore therapies to protect mammalian brain from low-oxygen insults.
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Affiliation(s)
- David W Hogg
- Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada, M5S 3G5
| | - Matthew E Pamenter
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - David J Dukoff
- Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada, M5S 3G5
| | - Leslie T Buck
- Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada, M5S 3G5.,Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada, M5S 3G5
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23
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Hermann PM, Watson SN, Wildering WC. Phospholipase A2 - nexus of aging, oxidative stress, neuronal excitability, and functional decline of the aging nervous system? Insights from a snail model system of neuronal aging and age-associated memory impairment. Front Genet 2014; 5:419. [PMID: 25538730 PMCID: PMC4255604 DOI: 10.3389/fgene.2014.00419] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Accepted: 11/13/2014] [Indexed: 02/02/2023] Open
Abstract
The aging brain undergoes a range of changes varying from subtle structural and physiological changes causing only minor functional decline under healthy normal aging conditions, to severe cognitive or neurological impairment associated with extensive loss of neurons and circuits due to age-associated neurodegenerative disease conditions. Understanding how biological aging processes affect the brain and how they contribute to the onset and progress of age-associated neurodegenerative diseases is a core research goal in contemporary neuroscience. This review focuses on the idea that changes in intrinsic neuronal electrical excitability associated with (per)oxidation of membrane lipids and activation of phospholipase A2 (PLA2) enzymes are an important mechanism of learning and memory failure under normal aging conditions. Specifically, in the context of this special issue on the biology of cognitive aging we portray the opportunities offered by the identifiable neurons and behaviorally characterized neural circuits of the freshwater snail Lymnaea stagnalis in neuronal aging research and recapitulate recent insights indicating a key role of lipid peroxidation-induced PLA2 as instruments of aging, oxidative stress and inflammation in age-associated neuronal and memory impairment in this model system. The findings are discussed in view of accumulating evidence suggesting involvement of analogous mechanisms in the etiology of age-associated dysfunction and disease of the human and mammalian brain.
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Affiliation(s)
- Petra M Hermann
- Department of Biological Sciences, University of Calgary Calgary, AB, Canada ; Department of Physiology and Pharmacology, University of Calgary Calgary, AB, Canada
| | - Shawn N Watson
- Department of Biological Sciences, University of Calgary Calgary, AB, Canada
| | - Willem C Wildering
- Department of Biological Sciences, University of Calgary Calgary, AB, Canada ; Department of Physiology and Pharmacology, University of Calgary Calgary, AB, Canada ; Hotchkiss Brain Institute, University of Calgary Calgary, AB, Canada
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