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Buján GE, D'Alessio L, Serra HA, Molina SJ, Guelman LR. Behavioral alterations induced by intermittent ethanol intake and noise exposure in adolescent rats. Eur J Neurosci 2022; 55:1756-1773. [PMID: 35342999 DOI: 10.1111/ejn.15657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 03/04/2022] [Accepted: 03/22/2022] [Indexed: 11/27/2022]
Abstract
Alcohol intake and exposure to noise are common activities of human adolescents performed in entertainment contexts worldwide that can induce behavioral disturbances. Therefore, the aim of the present work was to investigate in an experimental model of adolescent animals whether noise exposure and intermittent ethanol intake, when present individually or sequentially, might be able to modify different behaviors. Adolescent Wistar rats of both sexes were subjected to voluntary intermittent ethanol intake for 1 week followed by exposure to noise for 2 h and tested in a battery of behavioral tasks. Data show that males exposed to noise experienced a deficit in associative memory (AM), increase in anxiety-like behaviors (ALB) and altered reaction to novelty (RN) when compared with sham animals, whereas females also showed an increase in risk assessment behaviors (RAB) and a decrease in exploratory activity (EA). In contrast, ethanol intake induced an increase in RAB and RN in males and females, whereas females also showed a deficit in AM and EA as well as an increase in ALB. When ethanol was ingested before noise exposure, most parameters were counteracted both in male and females, but differed among sexes. In consequence, it could be hypothesized that an environmental acute stressor like noise might trigger a behavioral counteracting induced by a previous repeated exposure to a chemical agent such as ethanol, leading to a compensation of a non-adaptive behavior and reaching a better adjustment to the environment.
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Affiliation(s)
- Gustavo Ezequiel Buján
- Universidad de Buenos Aires. Facultad de Medicina. 1ª Cátedra de Farmacología, Buenos Aires, Argentina
| | - Luciana D'Alessio
- Universidad de Buenos Aires. Facultad de Medicina. 1ª Cátedra de Farmacología, Buenos Aires, Argentina.,Universidad de Buenos Aires. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología Celular y Neurociencias (IBCN, UBA-CONICET). Facultad de Medicina, Buenos Aires, Argentina
| | - Héctor Alejandro Serra
- Universidad de Buenos Aires. Facultad de Medicina. 1ª Cátedra de Farmacología, Buenos Aires, Argentina
| | - Sonia Jazmín Molina
- Universidad de Buenos Aires. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET). Facultad de Medicina, Buenos Aires, Argentina
| | - Laura Ruth Guelman
- Universidad de Buenos Aires. Facultad de Medicina. 1ª Cátedra de Farmacología, Buenos Aires, Argentina.,Universidad de Buenos Aires. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET). Facultad de Medicina, Buenos Aires, Argentina
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2
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Affiliation(s)
- Sonia Jazmín Molina
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina, Buenos Aires, Argentina
| | - Laura Ruth Guelman
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina; Universidad de Buenos Aires, Facultad de Medicina, 1a Cátedra de Farmacología, Buenos Aires, Argentina
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Molina SJ, Lietti ÁE, Carreira Caro CS, Buján GE, Guelman LR. Effects of early noise exposure on hippocampal-dependent behaviors during adolescence in male rats: influence of different housing conditions. Anim Cogn 2021; 25:103-120. [PMID: 34322771 DOI: 10.1007/s10071-021-01540-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 07/13/2021] [Accepted: 07/21/2021] [Indexed: 10/20/2022]
Abstract
Central nervous system (CNS) development is a very complex process that can be altered by environmental stimuli such as noise, which can generate long-term auditory and/or extra-auditory impairments. We have previously reported that early noise exposure can induce hippocampus-related behavioral alterations in postnatal day (PND) 28 adolescent rats. Furthermore, we recently found biochemical modifications in the hippocampus (HC) of these animals that seemed to endure even in more mature animals (i.e. PND35) and that have not been studied along with behavioral correlates. Thus, the aim of this work was to reveal novel data about the effects of early noise exposure on hippocampal-dependent behaviors in more mature animals. Additionally, extended enriched environment (EE) housing was evaluated to determine its capacity to induce behavioral modifications, either by its neuroprotective ability or the greater stimulation that it generates. Male Wistar rats were exposed to different noise schemes at PND7 or PND15. Upon weaning, some animals were transferred to EE whereas others were kept in standard cages. At PND35, different hippocampal-dependent behavioral assessments were performed. Results showed noise-induced behavioral changes that differed according to the scheme and age of exposure used. In addition, housing in an EE was effective either in preventing some of these changes or in inducing the appearance of new behavioral modifications. These findings suggest that CNS development would be sensitive to the effects of different type of environmental stimuli such as noise or enriched housing, leading to maladaptive behavioral changes that last even until adolescence.
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Affiliation(s)
- Sonia Jazmín Molina
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina, Paraguay 2155, Piso 15, 1121, Buenos Aires, Argentina.
| | - Ángel Emanuel Lietti
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina, Paraguay 2155, Piso 15, 1121, Buenos Aires, Argentina
| | - Candela Sofía Carreira Caro
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina, Paraguay 2155, Piso 15, 1121, Buenos Aires, Argentina
| | - Gustavo Ezequiel Buján
- Universidad de Buenos Aires, Facultad de Medicina, 1ª Cátedra de Farmacología, Buenos Aires, Argentina
| | - Laura Ruth Guelman
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina, Paraguay 2155, Piso 15, 1121, Buenos Aires, Argentina.,Universidad de Buenos Aires, Facultad de Medicina, 1ª Cátedra de Farmacología, Buenos Aires, Argentina
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Molina SJ, Buján GE, Guelman LR. Noise-induced hippocampal oxidative imbalance and aminoacidergic neurotransmitters alterations in developing male rats: Influence of enriched environment during adolescence. Dev Neurobiol 2021; 81:164-188. [PMID: 33386696 DOI: 10.1002/dneu.22806] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 12/21/2020] [Accepted: 12/26/2020] [Indexed: 12/21/2022]
Abstract
Living in big cities might involuntarily expose people to high levels of noise causing auditory and/or extra-auditory impairments, including adverse effects on central nervous system (CNS) areas such as the hippocampus. In particular, CNS development is a very complex process that can be altered by environmental stimuli. We have previously shown that noise exposure of developing rats can induce hippocampal-related behavioral alterations. However, noise-induced biochemical alterations had not been studied yet. Thus, the aim of this work was to assess whether early noise exposure can affect rat hippocampal oxidative state and aminoacidergic neurotransmission tone. Additionally, the effectiveness of an enriched environment (EE) as a neuroprotective strategy was evaluated. Male Wistar rats were exposed to different noise schemes at 7 or 15 days after birth. Upon weaning, some animals were transferred to an EE whereas others were kept in standard cages. Short- and long-term measurements were performed to evaluate reactive oxygen species, thioredoxins levels and catalase activity as indicators of hippocampal oxidative status as well as glutamic acid decarboxylase and a subtype of glutamate transporter to evaluate aminoacidergic neurotransmission tone. Results showed noise-induced changes in hippocampal oxidative state and aminoacidergic neurotransmission markers that lasted until adolescence and differed according to the scheme and the age of exposure. Finally, EE housing was effective in preventing some of these changes. These findings suggest that CNS development seems to be sensitive to the effects of stressors such as noise, as well as those of an environmental stimulation, favoring prompt and lasting molecular changes.
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Affiliation(s)
- Sonia Jazmín Molina
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina, Buenos Aires, Argentina
| | - Gustavo Ezequiel Buján
- Universidad de Buenos Aires, Facultad de Medicina, 1ª Cátedra de Farmacología, Buenos Aires, Argentina
| | - Laura Ruth Guelman
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina, Buenos Aires, Argentina.,Universidad de Buenos Aires, Facultad de Medicina, 1ª Cátedra de Farmacología, Buenos Aires, Argentina
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D'Alessio L, Korman GP, Sarudiansky M, Guelman LR, Scévola L, Pastore A, Obregón A, Roldán EJA. Reducing Allostatic Load in Depression and Anxiety Disorders: Physical Activity and Yoga Practice as Add-On Therapies. Front Psychiatry 2020; 11:501. [PMID: 32581876 PMCID: PMC7287161 DOI: 10.3389/fpsyt.2020.00501] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 05/18/2020] [Indexed: 12/23/2022] Open
Abstract
The allostatic load (AL) index constitutes a useful tool to objectively assess the biological aspects of chronic stress in clinical practice. AL index has been positively correlated with cumulative chronic stress (physical and psychosocial stressors) and with a high risk to develop pathological conditions (e.g., metabolic syndrome, cardiovascular pathology, inflammatory disorders) and the so-called stress-related psychiatric disorders, including anxiety and depressive disorders. Chronic stress has negative effects on brain neuroplasticity, especially on hippocampal neurogenesis and these effects may be reversed by antidepressant treatments. Several evidences indicate that non-pharmacological interventions based on physical activity and yoga practice may add synergizing benefits to classical treatments (antidepressant and benzodiazepines) for depression and anxiety, reducing the negative effects of chronic stress. The aim of this review is to provide a general overview of current knowledge on AL and chronic stress in relation to depression and anxiety, physical activity and yoga practice.
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Affiliation(s)
- Luciana D'Alessio
- Universidad de Buenos Aires, Facultad de Medicina, IBCN-CONICET, Buenos Aires, Argentina.,Universidad de Buenos Aires, Hospital Ramos Mejía, Buenos Aires, Argentina
| | - Guido Pablo Korman
- Universidad de Buenos Aires, Facultad de Psicología, CAEA-CONICET, Buenos Aires, Argentina
| | - Mercedes Sarudiansky
- Universidad de Buenos Aires, Facultad de Psicología, CAEA-CONICET, Buenos Aires, Argentina
| | - Laura Ruth Guelman
- Universidad de Buenos Aires, Facultad de Medicina, CEFYBO-CONICET, Buenos Aires, Argentina
| | - Laura Scévola
- Universidad de Buenos Aires, Hospital Ramos Mejía, Buenos Aires, Argentina
| | | | - Amilcar Obregón
- Dirección Médica y Científica, Gador SA, Buenos Aires, Argentina
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6
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Molina SJ, Buján GE, Rodriguez Gonzalez M, Capani F, Gómez-Casati ME, Guelman LR. Exposure of Developing Male Rats to One or Multiple Noise Sessions and Different Housing Conditions: Hippocampal Thioredoxin Changes and Behavioral Alterations. Front Behav Neurosci 2019; 13:182. [PMID: 31456671 PMCID: PMC6700388 DOI: 10.3389/fnbeh.2019.00182] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 07/23/2019] [Indexed: 01/21/2023] Open
Abstract
Exposure of developing rats to noise has shown to induce hippocampal-related behavioral alterations that were prevented after a week of housing in an enriched environment. However, neither the effect of repeated exposures nor its impact on key endogenous antioxidants had been studied yet. Thus, the aim of the present work was to reveal novel data about hippocampal oxidative state through the measurement of possible age-related differences in the levels of hippocampal thioredoxins in rats exposed to noise at different developmental ages and subjected to different schemes and housing conditions. In addition, the possibility that oxidative changes could underlie hippocampal-related behavioral changes was also analyzed. Developing male Wistar rats were exposed to noise for 2 h, either once or for 5 days. Upon weaning, some animals were transferred to an enriched cage for 1 week, whereas others were kept in standard cages. One week later, auditory and behavioral assessments, as well as measurement of hippocampal thioredoxin, were performed. Whereas no changes in the auditory function were observed, significant behavioral differences were found, that varied according to the age, scheme of exposure and housing condition. In addition, a significant increase in Trx-1 levels was found in all noise-exposed groups housed in standard cages. Housing animals in an enriched environment for 1 week was effective in preventing most of these changes. These findings suggest that animals become less susceptible to undergo behavioral alterations after repeated exposure to an environmental challenge, probably due to the ability of adaptation to an unfavorable condition. Moreover, it could be hypothesized that damage to younger individuals could be more easily prevented by a housing manipulation.
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Affiliation(s)
- Sonia Jazmín Molina
- Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Gustavo Ezequiel Buján
- Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Buenos Aires, Argentina
- Facultad de Medicina, Cátedra de Farmacología, Universidad de Buenos Aires, Buenos Aires, Argentina
| | | | - Francisco Capani
- Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Investigaciones Cardiológicas (ININCA, UBA-CONICET), Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago de Chile, Chile
| | | | - Laura Ruth Guelman
- Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Facultad de Medicina, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Buenos Aires, Argentina
- Facultad de Medicina, Cátedra de Farmacología, Universidad de Buenos Aires, Buenos Aires, Argentina
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Miceli M, Molina SJ, Forcada A, Acosta GB, Guelman LR. Voluntary alcohol intake after noise exposure in adolescent rats: Hippocampal-related behavioral alterations. Brain Res 2017; 1679:10-18. [PMID: 29113737 DOI: 10.1016/j.brainres.2017.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 10/25/2017] [Accepted: 11/01/2017] [Indexed: 11/16/2022]
Abstract
Different physical or chemical agents, such as noise or alcohol, can induce diverse behavioral and biochemical alterations. Considering the high probability of young people to undergo consecutive or simultaneous exposures, the aim of the present work was to investigate in an animal model if noise exposure at early adolescence could induce hippocampal-related behavioral changes that might be modified after alcohol intake. Male Wistar rats (28-days-old) were exposed to noise (95-97 dB, 2 h). Afterwards, animals were allowed to voluntarily drink alcohol (10% ethanol in tap water) for three consecutive days, using the two-bottle free choice paradigm. After that, hippocampal-related memory and anxiety-like behavior tests were performed. Results show that whereas noise-exposed rats presented deficits in habituation memory, those who drank alcohol exhibited impairments in associative memory and anxiety-like behaviors. In contrast, exposure to noise followed by alcohol intake showed increases in exploratory and locomotor activities as well as in anxiety-like behaviors, unlike what was observed using each agent separately. Finally, lower levels of alcohol intake were measured in these animals when compared with those that drank alcohol and were not exposed to noise. Present findings demonstrate that exposure to physical and chemical challenges during early adolescence might induce behavioral alterations that could differ depending on the schedule used, suggesting a high vulnerability of rat developing brain to these socially relevant agents.
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Affiliation(s)
- M Miceli
- Universidad de Buenos Aires, Facultad de Medicina, 1ª Cátedra de Farmacología, Buenos Aires, Argentina
| | - S J Molina
- Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Buenos Aires, Argentina
| | - A Forcada
- Universidad de Buenos Aires, Facultad de Medicina, 1ª Cátedra de Farmacología, Buenos Aires, Argentina
| | - G B Acosta
- Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Instituto de Investigaciones Farmacológicas (ININFA, UBA-CONICET), Buenos Aires, Argentina
| | - L R Guelman
- Universidad de Buenos Aires, Facultad de Medicina, 1ª Cátedra de Farmacología, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Centro de Estudios Farmacológicos y Botánicos (CEFyBO, UBA-CONICET), Buenos Aires, Argentina.
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Saraceno GE, Caceres LG, Guelman LR, Castilla R, Udovin LD, Ellisman MH, Brocco MA, Capani F. Consequences of excessive plasticity in the hippocampus induced by perinatal asphyxia. Exp Neurol 2016; 286:116-123. [PMID: 27578426 DOI: 10.1016/j.expneurol.2016.08.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 08/21/2016] [Accepted: 08/26/2016] [Indexed: 01/10/2023]
Abstract
Perinatal asphyxia (PA) is one of the most frequent risk factors for several neurodevelopmental disorders (NDDs) of presumed multifactorial etiology. Dysfunction of neuronal connectivity is thought to play a central role in the pathophysiology of NDDs. Because underlying causes of some NDDs begin before/during birth, we asked whether this clinical condition might affect accurate establishment of neural circuits in the hippocampus as a consequence of disturbed brain plasticity. We used a murine model that mimics the pathophysiological processes of perinatal asphyxia. Histological analyses of neurons (NeuN), dendrites (MAP-2), neurofilaments (NF-M/Hp) and correlative electron microscopy studies of dendritic spines were performed in Stratum radiatum of the hippocampal CA1 area after postnatal ontogenesis. Protein and mRNA analyses were achieved by Western blot and RT-qPCR. Behavioral tests were also carried out. NeuN abnormal staining and spine density were increased. RT-qPCR assays revealed a β-actin mRNA over-expression, while Western blot analysis showed higher β-actin protein levels in synaptosomal fractions in experimental group. M6a expression, protein involved in filopodium formation and synaptogenesis, was also increased. Furthermore, we found that PI3K/Akt/GSK3 pathway signaling, which is involved in synaptogenesis, was activated. Moreover, asphyctic animals showed habituation memory changes in the open field test. Our results suggest that abnormal synaptogenesis induced by PA as a consequence of excessive brain plasticity during brain development may contribute to the etiology of the NDDs. Consequences of this altered synaptic maturation can underlie some of the later behavioral deficits observed in NDDs.
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Affiliation(s)
- G E Saraceno
- ININCA, Universidad de Buenos Aires (UBA)-CONICET, Buenos Aires, Argentina
| | - L G Caceres
- Facultad de Medicina (UBA) CEFyBO-CONICET, Buenos Aires, Argentina
| | - L R Guelman
- Facultad de Medicina (UBA) CEFyBO-CONICET, Buenos Aires, Argentina
| | - R Castilla
- ININCA, Universidad de Buenos Aires (UBA)-CONICET, Buenos Aires, Argentina
| | - L D Udovin
- ININCA, Universidad de Buenos Aires (UBA)-CONICET, Buenos Aires, Argentina
| | - M H Ellisman
- Department of Neuroscience, Department of Neuroscience, National Center for Electron Microscopy and Imaging Research, UCSD, United States
| | - M A Brocco
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH), UNSAM-CONICET, Buenos Aires, Argentina
| | - F Capani
- ININCA, Universidad de Buenos Aires (UBA)-CONICET, Buenos Aires, Argentina; Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Chile.
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Molina SJ, Miceli M, Guelman LR. Noise exposure and oxidative balance in auditory and extra-auditory structures in adult and developing animals. Pharmacological approaches aimed to minimize its effects. Pharmacol Res 2015; 109:86-91. [PMID: 26657417 DOI: 10.1016/j.phrs.2015.11.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 11/23/2015] [Accepted: 11/25/2015] [Indexed: 10/22/2022]
Abstract
Noise coming from urban traffic, household appliances or discotheques might be as hazardous to the health of exposed people as occupational noise, because may likewise cause hearing loss, changes in hormonal, cardiovascular and immune systems and behavioral alterations. Besides, noise can affect sleep, work performance and productivity as well as communication skills. Moreover, exposure to noise can trigger an oxidative imbalance between reactive oxygen species (ROS) and the activity of antioxidant enzymes in different structures, which can contribute to tissue damage. In this review we systematized the information from reports concerning noise effects on cell oxidative balance in different tissues, focusing on auditory and non-auditory structures. We paid specific attention to in vivo studies, including results obtained in adult and developing subjects. Finally, we discussed the pharmacological strategies tested by different authors aimed to minimize the damaging effects of noise on living beings.
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Affiliation(s)
- S J Molina
- Cátedra de Farmacología, Facultad de Medicina, UBA and Centro de Estudios Farmacológicos y Botánicos, UBA-CEFYBO-CONICET, Buenos Aires, Argentina
| | - M Miceli
- Cátedra de Farmacología, Facultad de Medicina, UBA and Centro de Estudios Farmacológicos y Botánicos, UBA-CEFYBO-CONICET, Buenos Aires, Argentina
| | - L R Guelman
- Cátedra de Farmacología, Facultad de Medicina, UBA and Centro de Estudios Farmacológicos y Botánicos, UBA-CEFYBO-CONICET, Buenos Aires, Argentina.
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Caceres LG, Cid MP, Uran SL, Zorrilla Zubilete MA, Salvatierra NA, Guelman LR. Pharmacological alterations that could underlie radiation-induced changes in associative memory and anxiety. Pharmacol Biochem Behav 2013; 111:37-43. [PMID: 23958578 DOI: 10.1016/j.pbb.2013.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 08/02/2013] [Accepted: 08/08/2013] [Indexed: 11/30/2022]
Abstract
It is widely known that ionizing radiation is a physical agent broadly used to kill tumor cells during human cancer therapy. Unfortunately, adjacent normal tissues can concurrently undergo undesirable cell injury. Previous data of our laboratory demonstrated that exposure of developing rats to ionizing radiations induced a variety of behavioral differences respect to controls, including changes in associative memory and in anxiety state. However, there is a lack of data concerning modifications in different related pharmacological intermediaries. Therefore, the aim of the present study was to investigate whether the behavioral differences observed in young animals irradiated at birth might be underlain by early changes in PKCß1 levels which, in turn, could lead to changes in hippocampal GABAergic neurotransmission. Male Wistar rats were irradiated with 5Gy of X rays between 24 and 48 h after birth. Different pharmacological markers related to the affected behavioral tasks were assessed in control and irradiated hippocampus at 15 and 30 days, namely GABAA receptor, GAD65-67, ROS and PKCß1. Results showed that all measured parameters were increased in the hippocampus of 30-days-old irradiated animals. In contrast, in the hippocampus of 15-days-old irradiated animals only the levels of PKCß1 were decreased. These data suggest that PKCß1 might constitute a primary target for neonatal radiation damage on the hippocampus. Therefore, it could be hypothesized that an initial decrease in the levels of this protein can trigger a subsequent compensatory increase that, in turn, could be responsible for the plethora of biochemical changes that might underlie the previously observed behavioral alterations.
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Affiliation(s)
- L G Caceres
- 1ª Cátedra de Farmacología, Facultad de Medicina, UBA-CEFyBO-CONICET, Paraguay 2155, piso 15, (1121) Buenos Aires, Argentina
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Caceres LG, Aon Bertolino L, Saraceno GE, Zorrilla Zubilete MA, Uran SL, Capani F, Guelman LR. Hippocampal-related memory deficits and histological damage induced by neonatal ionizing radiation exposure. Role of oxidative status. Brain Res 2010; 1312:67-78. [DOI: 10.1016/j.brainres.2009.11.053] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 11/12/2009] [Accepted: 11/20/2009] [Indexed: 02/03/2023]
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Caceres LG, Rios H, Guelman LR. Long-lasting effects of neonatal ionizing radiation exposure on spatial memory and anxiety-like behavior. Ecotoxicol Environ Saf 2009; 72:895-904. [PMID: 18947871 DOI: 10.1016/j.ecoenv.2008.09.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Revised: 07/28/2008] [Accepted: 09/07/2008] [Indexed: 05/27/2023]
Abstract
Neonatal ionizing radiation exposure has been shown to induce a cerebellar cytoarchitecture disarrangement. Since cerebellar abnormalities have been linked to an impairment of behavioral functions, the aim of the present work was to investigate whether exposure of developing rats to ionizing radiations can produce behavioral deficits in the adult. Male Wistar rats were X-irradiated with 5Gy within 48h after birth and were tested in a radial maze and in an open field at 30 and 90 days post irradiation. Irradiated rats showed significative changes in spatial, exploratory, and procedural parameters in the radial maze, as well as a significative decrease in anxiety-like behavior, assessed in the open field. These results suggest that ionizing radiations can induce long-lasting spatial memory and anxiety-related changes. A relationship with radiation-induced cerebellar cytoarchitecture abnormalities supports the hypothesis that cerebellar integrity seems to be critical to achieve spatial performance and emotional behavior establishment.
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Affiliation(s)
- Lucila Guadalupe Caceres
- 1 feminine Cátedra de Farmacología, Departamento de Farmacología, Facultad de Medicina, UBA, Paraguay 2155-piso 15 (1121), Buenos Aires, Argentina
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Palumbo ML, Fosser NS, Rios H, Zorrilla Zubilete MA, Guelman LR, Cremaschi GA, Genaro AM. Loss of hippocampal neuronal nitric oxide synthase contributes to the stress-related deficit in learning and memory. J Neurochem 2007; 102:261-74. [PMID: 17419805 DOI: 10.1111/j.1471-4159.2007.04528.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nitric oxide (NO) has been involved in many pathophysiological brain processes. However, the exact role of NO in the cognitive deficit associated to chronic stress exposure has not been elucidated. In this study, we investigated the participation of hippocampal NO production and their regulation by protein kinase C (PKC) in the memory impairment induced in mice subjected to chronic mild stress model (CMS). CMS mice showed a poor learning performance in both open field and passive avoidance inhibitory task respect to control mice. Histological studies showed a morphological alteration in the hippocampus of CMS mice. On the other hand, chronic stress induced a diminished NO production by neuronal nitric oxide synthase (nNOS) correlated with an increment in gamma and zeta PKC isoenzymes. Partial restoration of nNOS activity was obtained after PKC activity blockade. NO production by inducible nitric oxide synthase isoform was not detected. The magnitude of oxidative stress, evaluated by reactive oxygen species production, after excitotoxic levels of NMDA was increased in hippocampus of CMS mice. Moreover, ROS formation was higher in the presence of nNOS inhibitor in both control and CMS mice. Finally, treatment of mice with nNOS inhibitors results in behavioural alterations similar to those observed in CMS animals. These findings suggest a novel role for nNOS showing protective activity against insults that trigger tissue toxicity leading to memory impairments.
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Affiliation(s)
- María Laura Palumbo
- CEFYBO-CONICET and 1a. Cát. de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
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Di Toro CG, Di Toro PA, Zieher LM, Guelman LR. Sensitivity of cerebellar glutathione system to neonatal ionizing radiation exposure. Neurotoxicology 2006; 28:555-61. [PMID: 17267041 DOI: 10.1016/j.neuro.2006.12.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Revised: 12/05/2006] [Accepted: 12/13/2006] [Indexed: 01/16/2023]
Abstract
Reactive oxygen species (ROS) are relevant components of living organisms that, besides their role in the regulation of different important physiological functions, when present in excess are capable to affect cell oxidative status, leading to damage of cellular molecules and disturbance of normal cell function. ROS accumulation has been associated with a variety of conditions such as neurodegenerative diseases and ionizing radiation exposure. Cell ability to counteract ROS overproduction depends on the capacity of the endogenous antioxidant defenses--which includes the glutathione (GSH) system--to cope with. Since developing central nervous system (CNS) is especially sensitive to ROS-induced damage, the aim of the present work was to evaluate ROS, reduced GSH and oxidized glutathione (GSSG) levels in the cerebellum at different developmental ages after irradiation, in order to test if any changes were induced on these key oxidative stress-related cellular markers that might explain the high cerebellar vulnerability to radiation-induced injury. Since intracellular levels of GSH are maintained by glutathione reductase (GSHr), this enzymatic activity was also evaluated. Newborn Wistar rats were irradiated in their cephalic ends and the different parameters were measured, from 1h to 90 days post-irradiation. Results showed that an early transient increase in ROS levels followed by a decrease in cerebellar weight at 3-5 days post-irradiation were induced. An increase in cerebellar GSH levels was induced at 30 days after irradiation, together with a decrease in GSHr activity. These results support the hypothesis that ROS may represent a marker of damage prior to radiation-induced cell death. In contrast, it would be suggested that GSH system might play a role in the compensatory mechanisms triggered to counteract radiation-induced cerebellar damage.
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Affiliation(s)
- C G Di Toro
- 1a Cátedra de Farmacología, Facultad de Medicina, UBA, Buenos Aires, Argentina
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Zorrilla Zubilete MA, Ríos H, Silberman DM, Guelman LR, Ricatti MJ, Genaro AM, Zieher LM. Altered nitric oxide synthase and PKC activities in cerebellum of gamma-irradiated neonatal rats. Brain Res 2005; 1051:8-16. [PMID: 15993387 DOI: 10.1016/j.brainres.2005.05.046] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Revised: 05/12/2005] [Accepted: 05/14/2005] [Indexed: 11/24/2022]
Abstract
In this study, we show that one single dose of gamma-irradiation at birth induces an inhibition of the cerebellar calcium dependent nitric oxide synthase (NOS) activity, probably correlated to the motor abnormalities and the disarrangement in the cerebellar cytoarchitecture observed in adult rats. This decrease in calcium dependent NOS activity could be associated with an increased protein kinase C (PKC) activity. PKC inhibition partially restores calcium dependent NOS activity, indicating that PKC activity could be negatively modulating the catalytic activity of calcium dependent NOS. These findings suggest that a decrease in nitric oxide (NO) production and the related increase in PKC activity could be intracellular events that participate in the onset of motor and cerebellar abnormalities induced by postnatal gamma-irradiation at early stages of life.
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Affiliation(s)
- María A Zorrilla Zubilete
- 1a Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires (UBA), 2155 Paraguay St. Piso 15, (1121) Ciudad de Buenos Aires, Argentina.
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16
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Guelman LR, Cabana JI, del Luján Pagotto RM, Zieher LM. Ionizing radiation‐induced damage on developing cerebellar granule cells cultures can be prevented by an early amifostine post‐treatment. Int J Dev Neurosci 2004; 23:1-7. [PMID: 15730881 DOI: 10.1016/j.ijdevneu.2004.10.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2004] [Revised: 09/30/2004] [Accepted: 10/06/2004] [Indexed: 11/28/2022] Open
Abstract
Developing central nervous system (CNS) is highly sensitive to ionizing radiation due, in part, to reactive oxygen species (ROS) damage. A variety of compounds able to protect brain cells essentially by decreasing ROS production have been widely used to confirm ROS participation in different mechanisms of brain injury, as well as to evaluate them as therapeutic tools. To test if ionizing radiation-induced damage on immature cerebellar granule cells is mainly mediated by ROS accumulation, a free radical scavenger--amifostine (amf)--was used in an in vitro model. Moreover, the amf therapeutic effect was investigated. Results show that only an early (20-30 min) post-treatment with amf, acting through an antioxidant mechanism, has been effective in preventing cerebellar granule cell loss observed after ionizing radiation exposure in vitro. These data suggest that immature cerebellar granule cells grown in vitro are highly vulnerable to ROS damage and that a therapeutic intervention could be effective in a narrow temporal window. Moreover, radiation-induced cell death can be partially prevented by a complete limitation of ROS generation, suggesting that other mechanisms besides oxidative stress would also be responsible for the cellular damage found in this model.
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Affiliation(s)
- Laura Ruth Guelman
- 1 Cátedra de Farmacología, Facultad de Medicina, UBA, Paraguay 2155, piso 15, 1121 Buenos Aires, Argentina.
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Guelman LR, Pagotto RMDL, Di Toro CG, Zieher LM. Deferoxamine antioxidant activity on cerebellar granule cells γ-irradiated in vitro. Neurotoxicol Teratol 2004; 26:477-83. [PMID: 15113608 DOI: 10.1016/j.ntt.2004.02.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2003] [Revised: 02/02/2004] [Accepted: 02/03/2004] [Indexed: 10/26/2022]
Abstract
Oxidative stress has been implicated in the pathogenesis of many neurodegenerative and neurological disorders, with reactive oxygen species (ROS) as part of the intracellular effectors of damage formed in the presence of an excess of iron. Ionizing radiation induces tissue damage on developing CNS through different simultaneous mechanisms, including ROS-induced oxidative damage; therefore, exogenously added iron chelators might contribute to protect cells from free-radical injury. Cerebellar granule cells grown in vitro were exposed to 0.3 Gy of gamma radiation, and 30-60 min before irradiation, deferoxamine (Dfx), an iron chelator, was added at different nontoxic concentrations. When cell viability and ROS levels were evaluated in Dfx-treated cultures, a partial prevention of radiation-induced cell death and ROS increase were found, being this prevention concentration independent. These data support the involvement of an iron-driven hydroxyl radical formation pathway in the acute toxic mechanism of radiation in cultures of cerebellar granule cells, being ROS-induced oxidative damage one of the mechanisms through which radiation might induce cell death. Therefore, blocking ROS production through the use of a chelating agent, such as Dfx, would be a useful therapeutic tool in different experimental models.
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Affiliation(s)
- Laura Ruth Guelman
- 1a Cátedra de Farmacología and Instituto de Neurociencias Aplicadas, Facultad de Medicina, UBA, Paraguay 2155, piso 15 (1121) Buenos Aires, Argentina.
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Guelman LR, Zorrilla Zubilete MA, Rios H, Zieher LM. WR-2721 (amifostine, ethyol) prevents motor and morphological changes induced by neonatal X-irradiation. Neurochem Int 2003; 42:385-91. [PMID: 12510021 DOI: 10.1016/s0197-0186(02)00136-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Neonatal X-irradiation induces permanent abnormalities in cerebellar cortex cytoarchitecture and neurochemistry, as well as impairment in motor gait. The aim of the present work was to examine the potential protective properties of WR-2721 (Amifostine, Ethyol), a free radical scavenger, against the above mentioned alterations by using a previously described neuroprotection assessment protocol. Pre-irradiation treatment with amifostine was effective in partially preventing the cerebellar morphological damage and the motor gait impairment induced by ionizing radiation. No changes in cerebellar noradrenaline (NA) levels were detected in amifostine-treated irradiated animals. These results suggest that it is possible to counteract radiation-induced damage in the cerebella and motor gait of neonatal rats through oxygen free radical scavenger administration prior to irradiation. The presence of the agent before the injury occurs, favors the efficacy of amifostine neuroprotective activity. Clinical implications of this model are related to the daily exposure of many people to different sources of radiation (accidental, diagnostical or therapeutical).
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Affiliation(s)
- L R Guelman
- 1a Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires (UBA), Paraguay 2155-piso 15 (1121), Argentina.
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Guelman LR, Zorrilla Zubilete MA, Ríos H, Di Toro CG, Dopico AM, Zieher LM. Motor, cytoarchitectural and biochemical assessment of pharmacological neuroprotection against CNS damage induced by neonatal exposure to ionizing radiation. Brain Res Brain Res Protoc 2001; 7:203-10. [PMID: 11431121 DOI: 10.1016/s1385-299x(01)00060-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Exposure of neonatal rats to a 5 Gy single dose of X-irradiation induces permanent abnormalities in cerebellar cortex cytoarchitecture and neurochemistry and motor function. This rodent model constitutes an useful tool to evaluate morphological, neurochemical and motor changes induced by ionizing radiation and the possible restorative effects of potential or clearly established neuroprotective drugs. After selection and administration of a neuroprotective agent to neonatally irradiated rats, quantitative evaluations of motor behavior (gait), cerebellar cortex cytoarchitecture and cerebellar monoamine levels are performed. Data are compared to those of both saline-injected, X-irradiated, and saline-injected, sham-irradiated controls. Evaluation of data from the different experimental groups is performed at postnatal days 30 and 90. After this postnatal interval, radiation-induced damage of cerebellar function in nonprotected rodents is considered to be permanent. The longitudinal evaluation of various parameters in the different experimental groups through a multidisciplinary approach, allows determination of the variables that are more sensitive to X-irradiation-induced damage and/or neuroprotective agent-induced restoration. Given the well-known correspondence in cerebellar developmental stages between rodents and humans, this model and related studies bring health-related implications, considering the accidental or therapeutic exposure of developing human beings to ionizing radiation.
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Affiliation(s)
- L R Guelman
- 1a Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, UBA, Paraguay 2155, piso 15, 1121 Buenos Aires, Argentina.
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Guelman LR, Zorrilla Zubilete MA, Ríos H, Dopico AM, Zieher LM. GM1 ganglioside treatment protects against long-term neurotoxic effects of neonatal X-irradiation on cerebellar cortex cytoarchitecture and motor function. Brain Res 2000; 858:303-11. [PMID: 10708681 DOI: 10.1016/s0006-8993(99)02444-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Exposure of neonatal rats to a 5 Gy dose of X-irradiation induces permanent abnormalities in cerebellar cortex cytoarchitecture (disarrangement of Purkinje cells, reduction of thickness of granular cortex) and neurochemistry (late increase in noradrenaline levels), and motor function (ataxic gait). The neuroprotective effects of gangliosides have been demonstrated using a variety of CNS injuries, including mechanical, electrolytic, neurotoxic, ischemic, and surgical lesions. Here, we evaluated whether systemically administered GM1 ganglioside protects against the long-term CNS abnormalities induced by a single exposure to ionizing radiation in the early post-natal period. Thus, neonatal rats were exposed to 5 Gy X-irradiation, and subcutaneously injected with one dose (30 mg/kg weight) of GM1 on h after exposure followed by three daily doses. Both at post-natal days 30 and 90, gait and cerebellar cytoarchitecture in X-irradiated rats were significantly impaired when compared to age-matched controls. By contrast, both at post-natal days 30 and 90, gait in X-irradiated rats that were treated with GM1 was not significantly different from that in non-irradiated animals. Furthermore, at post-natal day 90, cerebellar cytoarchitecture was still well preserved in GM1-treated, X-irradiated animals. GM1 failed to modify the radiation-induced increase in cerebellar noradrenaline levels. Present data indicate that exogenous GM1, repeatedly administered after neonatal X-irradiation, produces a long-term radioprotection, demonstrated at both cytoarchitectural and motor levels.
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Affiliation(s)
- L R Guelman
- 1a Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155 piso 15, 1121, Buenos Aires, Argentina.
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Abstract
In this paper we describe the effects of X-radiation on the viability of cerebellar granule cells grown in culture. Cell cultures were exposed to X-rays 2 h after plating and then grown for 1-7 days. Two days after X-ray exposure with a dose-range of 0.1-2 Gy (acute effect), a significant decrease in neuronal number was observed. The magnitude of the lethal effect was directly correlated to the dose of X-ray applied. When the interval between plating and irradiation was increased, the acute lethal effect of X-rays decreased. 3H-thymidine incorporation was maximal during the first 24 h in vitro and decreased to nearly blank levels, after 72 h. In some experiments, cells present in each culture dish were counted at day 2 and at day 7. We observed that the number of cells present in sham-irradiated cultures decreased from day 2 to day 7, reflecting cell death after several days in vitro. The cell loss observed in X-irradiated cultures was significantly greater as compared with sham-irradiated cultures, confirming the deleterious effect of X-ray on cell survival. This effect was completely prevented by GM1 (6.5, 10 and 30 microM) added 48 h after X-ray exposure, but not 1 h after plating. We conclude that X-rays induce two different effects: an acute effect related to impaired DNA synthesis which is very active during the first 24 h in vitro, and a long-term effect owing to a sublethal damage in the surviving neuronal population.
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Affiliation(s)
- L R Guelman
- Comisión Nacional de Energía Atómica, Facultad de Medicina, Universidad de Buenos Aires, Argentina
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Guelman LR, Zieher LM, Zorrilla Zubilete MA, Dopico AM. Activities of monoamine oxidase-A and -B in adult rat cerebellum following neonatal X-irradiation. Neurosci Res 1996; 25:97-100. [PMID: 8808804 DOI: 10.1016/0168-0102(96)01022-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The activities of monoamine oxidases, MAO-A and MAO-B, were separately determined in the cerebellum (CE) from adult rats neonatally exposed to 5 Gy X-irradiation. They were found to be markedly reduced: 58% and 66% of values from nonirradiated, littermate controls. Since the specific activities of both isoenzymes (per mg tissue weight) were not significantly different from controls, the reduction of activity per CE is basically explained by the irradiation-induced cerebellar atrophy. The unmodified MAO-A specific activity makes it highly improbable that the increase in the cerebellar noradrenaline content, characteristic of neonatally X-irradiated rats, could be due to a decreased neuronal metabolism of noradrenaline by this enzyme.
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Affiliation(s)
- L R Guelman
- 1a Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Paraguay, Argentina
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Guelman LR, Zieher LM, Ríos H, Mayo J, Dopico AM. Motor abnormalities and changes in the noradrenaline content and the cytoarchitecture of developing cerebellum following X-irradiation at birth. Mol Chem Neuropathol 1993; 20:45-57. [PMID: 8251032 DOI: 10.1007/bf03160069] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have studied the developmental time-course of changes in the noradrenaline (NA) content of cerebellum (CE), cytoarchitecture of the cerebellar cortex, and motor abnormalities induced by the exposure of the cephalic end of rats to a single dose (5 Gy) of X-irradiation immediately after birth. At all ages examined, i.e., from postnatal (PN) d 5 to 90, CE from exposed animals show a marked atrophy, with an agranular cortex that has lost its layered structure. Purkinje cells are scattered at all depths in the cortex, and their primary dendrite is randomly oriented. The motor syndrome includes dystonia-like movements, a fine tremor, and an ataxic gait. Being progressive, the abnormal movements are evident from PN d 10, and fully developed by d 30. On the other hand, no differences in cerebellar NA content between X-irradiated rats and age-matched nonirradiated controls were detected from PN d 5 to 60. However, at PN d 90 a significant increase in NA content of CE from exposed animals is found when compared to either age-matched controls (+36%, p < 0.01), or data from irradiated rats obtained at PN d 5 to 60 (p < 0.01). These results indicate a temporal dissociation between the motor and cytoarchitectural abnormalities and the increase in cerebellar NA content produced by a single dose of X-rays at birth. The late increase in cerebellar NA content might represent a compensatory response of noradrenergic terminals to an altered information flow out of the cerebellar cortex induced by the ionizing noxa.
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Affiliation(s)
- L R Guelman
- Departamento de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Argentina
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