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Abhishek K, Mallick BN. Sleep loss disrupts decision-making ability and neuronal cytomorphology in zebrafish and the effects are mediated by noradrenaline acting on α1-adrenoceptor. Neuropharmacology 2024; 247:109861. [PMID: 38331315 DOI: 10.1016/j.neuropharm.2024.109861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 12/21/2023] [Accepted: 01/28/2024] [Indexed: 02/10/2024]
Abstract
Sleep is an instinct behavior, and its significance and functions are still an enigma. It is expressed throughout one's life and its loss affects psycho-somatic and physiological processes. We had proposed that it might maintain a fundamental property of the neurons and the brain. In that context, it was shown that sleep, rapid eye movement sleep (REMS) in particular, by regulating noradrenaline (NA), maintains the brain excitability. It was also reported that sleep-loss affected memory, reaction time and decision-making ability among others. However, as there was lack of clarity on the cause-and-effect relationship as to how the sleep-loss could affect these basic behaviors, their association was questioned and it was difficult to propose a cure or at least ways and means to ameliorate the symptoms. Also, we wanted to conduct the studies in a simpler model system so that conducting future molecular studies might be easier. Hence, using zebrafish as a model we evaluated if sleep-loss affected the basic decision-making ability, a cognitive process and if the effect was induced by NA. Indeed, our findings confirmed that upon sleep-deprivation, the cognitive decision-making ability of the prey zebrafish was compromised to protect itself by running away from the reach of the exposed predator Tiger Oscar (TO) fish. Also, we observed that upon sleep-loss the axonal arborization of the prey zebrafish brain was reduced. Interestingly, the effects were prevented by prazosin (PRZ), an α1-adrenoceptor (AR) antagonist and when the zebrafish recovered from the lost sleep.
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Affiliation(s)
- Kumar Abhishek
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Birendra Nath Mallick
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India; Amity Institute of Neuropsychology & Neurosciences, Amity University Uttar Pradesh, Sector 125, NOIDA, 201313, India.
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Todorović J, Dinčić M, Krstić DZ, Čolović MB, Ostojić JN, Kovačević S, Lopičić S, Spasić S, Brkić P, Milovanović A. The simultaneous action of acute paradoxical sleep deprivation and hypothyroidism modulates synaptosomal ATPases and acetylcholinesterase activities in rat brain. Sleep Med 2023; 105:14-20. [PMID: 36940515 DOI: 10.1016/j.sleep.2023.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 02/22/2023] [Accepted: 03/04/2023] [Indexed: 03/08/2023]
Abstract
BACKGROUND Thyroid dysfunctions as well as sleep abnormalities are usually followed by neurological, psychiatric and/or behavioral disorders. On the other hand, changes in the brain adenosine triphosphatases (ATPases) and acetylcholinesterase (AChE) activities show significant importance in pathogenetic pathways in the evolution of numerous neuropsychiatric diseases. METHODS This study aimed to evaluate the in vivo simultaneous effects of hypothyroidism and paradoxical sleep deprivation for 72 h on synaptosomalATPases and AChE activities of whole rat brains. In order to induce hypothyroidism, 6-n-propyl-2-thiouracil was administrated in drinking water during 21 days. The modified multiple platform method was used to induce paradoxical sleep deprivation. The AChE and ATPases activities were measured using spectrophotometric methods. RESULTS Hypothyroidism significantly increased the activity of Na+/K+-ATPase compared to other groups, while at the same time significantly decreased AChE activity compared to the CT and SD groups. Paradoxical sleep deprivation significantly increased AChE activity compared to other groups. The simultaneous effect of hypothyroidism and sleep deprivation reduced the activity of all three enzymes (for Na+/K+-ATPase between HT/SD and HT group p < 0.0001, SD group p < 0.001,CT group p = 0.013; for ecto-ATPases between HT/SD and HT group p = 0.0034, SD group p = 0.0001, CT group p = 0.0007; for AChE between HT/SD and HT group p < 0.05, SD group p < 0.0001, CT group p < 0.0001). CONCLUSIONS The effect of simultaneous existence of hypothyroidism and paradoxical sleep deprivation reduces the activity of the Na+/K+-ATPase, ecto-ATPases, and AChE, what is different from individual effect of hypothyroidism and paradoxical sleep deprivation itself. This knowledge could help in the choice of appropriate therapy in such condition.
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Affiliation(s)
- Jasna Todorović
- University of Belgrade, Faculty of Medicine, Institute of Pathological Physiology, Serbia.
| | - Marko Dinčić
- University of Belgrade, Faculty of Medicine, Institute of Pathological Physiology, Serbia.
| | - Danijela Z Krstić
- University of Belgrade, Faculty of Medicine, Institute of Medical Chemistry, Serbia.
| | - Mirjana B Čolović
- University of Belgrade, "Vinča" Institute of Nuclear Sciences-National Institute of Thе Republic of Serbia, Department of Physical Chemistry, Serbia.
| | - Jelena Nešović Ostojić
- University of Belgrade, Faculty of Medicine, Institute of Pathological Physiology, Serbia.
| | - Sanjin Kovačević
- University of Belgrade, Faculty of Medicine, Institute of Pathological Physiology, Serbia.
| | - Srđan Lopičić
- University of Belgrade, Faculty of Medicine, Institute of Pathological Physiology, Serbia.
| | - Svetolik Spasić
- University of Belgrade, Faculty of Medicine, Institute of Pathological Physiology, Serbia.
| | - Predrag Brkić
- University of Belgrade, Faculty of Medicine, Institute of Medical Physiology, Serbia.
| | - Aleksandar Milovanović
- University of Belgrade, Faculty of Medicine, Clinical Center of Serbia, Institute of Occupational Health, Serbia.
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Kukula O, Çiçekli MN, Şafak S, Günaydın C. Role of TRPV1 channels on glycogen synthase kinase-3β and oxidative stress in ouabain-induced bipolar disease. J Recept Signal Transduct Res 2021; 42:338-348. [PMID: 34304690 DOI: 10.1080/10799893.2021.1955928] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Bipolar disorder (BD) is a multifactorial chronic and refractory disease characterized by manic, depressive, and mixed mood episodes. Although epidemiological, and pathophysiological studies demonstrated a strong correlation between bipolar disorder and oxidative stress, precise etiology is still missing. Recent studies suggested the possible role of transient receptor potential channels (TRP) in the BD but, current knowledge is limited. Therefore, the current study investigates the possible role of TRPV1 in the ouabain-induced model of BD. The model was created with intracerebroventricular single dose ouabain (10-3 M) administration. Animals were treated with capsaicin, capsazepine, and lithium for seven days. Mania and depressive-like states were investigated with open-field, sucrose preference, and elevated plus maze tests. Oxidative stress was assessed by measuring total antioxidant and oxidant states, spectrophotometrically. The phosphorylation Glycogen synthase kinase-3β (GSK-3β) evaluated by western blotting. Our results demonstrated that capsaicin dose-dependently inhibited the ouabain-induced hyperlocomotion and depression. Although capsazepine exacerbated behavioral impairment, it did not show a significant effect on the antioxidant and oxidant states, and the effects of capsazepine on behaviors were abolished by combination with capsaicin. Additionally, capsaicin potently prevented the ouabain-induced decrease in GSK-3β phosphorylation. In contrast, capsazepine potentiated ouabain-induced decrease in GSK-3β phosphorylation and combination with capsaicin, suppressed the effect of capsazepine on GSK-3β phosphorylation. The effects of TRPV1 activation on oxidative stress and mania-like behaviors in the ouabain-induced BD model might be regulated by GSK-3β phosphorylation.
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Affiliation(s)
- Osman Kukula
- Department of Pharmacology, School of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Mustafa Nusret Çiçekli
- Department of Pharmacology, School of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Sinan Şafak
- Department of Pharmacology, School of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Caner Günaydın
- Department of Pharmacology, School of Medicine, Ondokuz Mayıs University, Samsun, Turkey
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Giri S, Ranjan A, Kumar A, Amar M, Mallick BN. Rapid eye movement sleep deprivation impairs neuronal plasticity and reduces hippocampal neuronal arborization in male albino rats: Noradrenaline is involved in the process. J Neurosci Res 2021; 99:1815-1834. [PMID: 33819353 DOI: 10.1002/jnr.24838] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/05/2021] [Accepted: 03/13/2021] [Indexed: 12/22/2022]
Abstract
Rapid eye movement sleep (REMS) favors brain development and memory, while it is decreased in neurodegenerative diseases. REMS deprivation (REMSD) affects several physiological processes including memory consolidation; however, its detailed mechanism(s) of action was unknown. REMS reduces, while REMSD elevates noradrenaline (NA) level in the brain; the latter induces several deficiencies and disorders, including changes in neuronal cytomorphology and apoptosis. Therefore, we proposed that REMS- and REMSD-associated modulation of NA level might affect neuronal plasticity and affect brain functions. Male albino rats were REMS deprived by flower-pot method for 6 days, and its effects were compared with home cage and large platform controls as well as post-REMSD recovered and REMS-deprived prazosin (α1-adrenoceptor antagonist)-treated rats. We observed that REMSD reduced CA1 and CA3 neuronal dendritic length, branching, arborization, and spine density, while length of active zone and expressions of pre- as well as post-synaptic proteins were increased as compared to controls; interestingly, prazosin prevented most of the effects in vivo. Studies on primary culture of neurons from chick embryo brain confirmed that NA at lower concentration(s) induced neuronal branching and arborization, while higher doses were destructive. The findings support our contention that REMSD adversely affects neuronal plasticity, branching, and synaptic scaffold, which explain the underlying cytoarchitectural basis of REMSD-associated patho-physio-behavioral changes. Consolidation of findings of this study along with that of our previous reports suggest that the neuronal disintegration could be due to either withdrawal of direct protective and proliferative role of low dose of NA or indirect effect of high dose of NA or both.
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Affiliation(s)
- Shatrunjai Giri
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Amit Ranjan
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.,Mahatma Gandhi Central University, Motihari, Bihar, India
| | - Awanish Kumar
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Megha Amar
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.,Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
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Flowerpot method for rapid eye movement sleep deprivation does not induce stress as defined by elevated serum corticosterone level in rats. Neurosci Lett 2021; 745:135631. [PMID: 33444674 DOI: 10.1016/j.neulet.2021.135631] [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: 08/03/2020] [Revised: 01/04/2021] [Accepted: 01/05/2021] [Indexed: 01/07/2023]
Abstract
Flowerpot method of rapid eye movement sleep (REMS) deprivation (REMSD) has been most extensively used in experiments to decipher the functions of REMS. The most common but serious criticism of this method has been presumed stress experienced by the experimental animals. The lack of systematic studies with appropriate controls to resolve this issue prompted this study. We have compared serum corticosterone levels as a marker of stress in male rats under REMSD by the flowerpot method and multiple types of control conditions. Additionally, to maintain consistency and uniformity of REMSD among groups, in the same rats, we estimated brain Na-K ATPase activity, which has been consistently reported to increase upon REMSD. The most effective method was one rat in single- or multiple-platforms set-up in a pool because it significantly increased Na-K ATPase activity without elevating serum corticosterone level. More than one rat in multiple platform set-up was ineffective and must be avoided. Also, large platform- and recovery-controls must be carried out simultaneously to rule out non-specific confounding effects.
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Lelkes Z. Ouabain, a Na–K-ATPase inhibitor, enhances wakefulness in rats. Neuropharmacology 2020; 176:108224. [DOI: 10.1016/j.neuropharm.2020.108224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 06/26/2020] [Accepted: 06/27/2020] [Indexed: 10/23/2022]
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Nawi A, Eu KL, Faris ANA, Wan Ahmad WAN, Noordin L. Lipid peroxidation in the descending thoracic aorta of rats deprived of REM sleep using the inverted flowerpot technique. Exp Physiol 2020; 105:1223-1231. [PMID: 32539237 DOI: 10.1113/ep088667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 06/08/2020] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Deprivation of rapid eye movement (REM) sleep is associated with increased oxidative stress, but its effects on the blood vessels are poorly documented. We investigated whether REM sleep deprivation induces oxidative stress and causes lipid peroxidation in the aorta. What is the main finding and its important? We demonstrate that REM sleep deprivation induces oxidative stress and mediates lipid peroxidation in the aorta. This can cause endothelial changes and increased blood pressure. These findings will contribute to the growing body of literature on the mechanism underlying the effects of sleep deprivation on cardiovascular disease. ABSTRACT Oxidative stress-mediated lipid peroxidation is a known cause of endothelial injury or dysfunction. Deprivation of rapid eye movement (REM) sleep is associated with oxidative stress. To date, the pathogenesis of increased blood pressure after sleep deprivation remains poorly understood, particularly in the REM sleep phase. Our aim was to investigate the effects of REM sleep deprivation on blood vessels in the REM sleep-deprived rat model. Twenty-eight male Sprague-Dawley rats were divided into four equal groups: free-moving control rats, rats deprived of REM sleep for 72 h (REMsd), tank control rats and 72 h sleep-recovered rats after 72 h of REM sleep deprivation. The rats were deprived of REM sleep using the inverted flowerpot technique. Food consumption, body weight gain and systolic blood pressure were monitored. At the end of the experiment, the descending thoracic aorta was isolated for the measurement of oxidative stress markers. Despite a significant increase in food consumption in the REMsd group compared with the other groups, there was a significant reduction in body weight gain. Systolic blood pressure also showed a significant increase in the REMsd group compared with the other groups. Superoxide dismutase activity was significantly lower and malondialdehyde concentrations significantly higher in the REMsd group compared with the other groups. Increased levels of malondialdehyde are suggestive of lipid peroxidation in the blood vessels, and oxidative stress may be attributed to the initiation of the process. The changes after REM sleep deprivation revert during sleep recovery. In conclusion, the findings of the present study provide convincing evidence that REM sleep deprivation induced lipid peroxidation, leading to endothelial damage.
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Affiliation(s)
- Afifah Nawi
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
| | - Koh Liew Eu
- Biomedicine Programme, School of Health Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
| | - Asma Nadia Ahmad Faris
- Biomedicine Programme, School of Health Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
| | - Wan Amir Nizam Wan Ahmad
- Biomedicine Programme, School of Health Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
| | - Liza Noordin
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
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Singh A, Das G, Kaur M, Mallick BN. Noradrenaline Acting on Alpha1 Adrenoceptor as well as by Chelating Iron Reduces Oxidative Burden on the Brain: Implications With Rapid Eye Movement Sleep. Front Mol Neurosci 2019; 12:7. [PMID: 30837837 PMCID: PMC6389636 DOI: 10.3389/fnmol.2019.00007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 01/10/2019] [Indexed: 12/20/2022] Open
Abstract
The noradrenaline (NA) level in the brain is reduced during rapid eye movement sleep (REMS). However, upon REMS deprivation (REMSD) its level is elevated, which induces apoptosis and the degeneration of neurons in the brain. In contrast, isolated studies have reported that NA possesses an anti-oxidant property, while REMSD reduces lipid peroxidation (LP) and reactive oxygen species (ROS). We argued that an optimum level of NA is likely to play a physiologically beneficial role. To resolve the contradiction and for a better understanding of the role of NA in the brain, we estimated LP and ROS levels in synaptosomes prepared from the brains of control and REMS deprived rats with or without in vivo treatment with either α1-adrenoceptor (AR) antagonist, prazosin (PRZ) or α2-AR agonist, clonidine (CLN). REMSD significantly reduced LP and ROS in synaptosomes; while the effect on LP was ameliorated by both PRZ and CLN; ROS was prevented by CLN only. Thereafter, we evaluated in vitro the effects of NA, vitamin E (Vit E), vitamin C (Vit C), and desferrioxamine (DFX, iron chelator) in modulating hydrogen peroxide (H2O2)-induced LP and ROS in rat brain synaptosomes, Neuro2a, and C6 cells. We observed that NA prevented ROS generation by chelating iron (inhibiting a Fenton reaction). Also, interestingly, a lower dose of NA protected the neurons and glia, while a higher dose damaged the neurons and glia. These in vitro and in vivo results are complementary and support our contention. Based on the findings, we propose that REMS maintains an optimum level of NA in the brain (an antioxidant compromised organ) to protect the latter from continuous oxidative onslaught.
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Affiliation(s)
- Abhishek Singh
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Gitanjali Das
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Manjeet Kaur
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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Reciprocal changes in noradrenaline and GABA levels in discrete brain regions upon rapid eye movement sleep deprivation in rats. Neurochem Int 2017; 108:190-198. [DOI: 10.1016/j.neuint.2017.03.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 03/19/2017] [Accepted: 03/24/2017] [Indexed: 12/11/2022]
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Narwade SC, Mallick BN, Deobagkar DD. Transcriptome Analysis Reveals Altered Expression of Memory and Neurotransmission Associated Genes in the REM Sleep Deprived Rat Brain. Front Mol Neurosci 2017; 10:67. [PMID: 28367113 PMCID: PMC5355427 DOI: 10.3389/fnmol.2017.00067] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 02/28/2017] [Indexed: 12/21/2022] Open
Abstract
Sleep disorders are associated with cognitive impairment. Selective rapid eye movement sleep (REMS) deprivation (REMSD) alters several physiological processes and behaviors. By employing NGS platform we carried out transcriptomic analysis in brain samples of control rats and those exposed to REMSD. The expression of genes involved in chromatin assembly, methylation, learning, memory, regulation of synaptic transmission, neuronal plasticity and neurohypophysial hormone synthesis were altered. Increased transcription of BMP4, DBH and ATP1B2 genes after REMSD supports our earlier findings and hypothesis. Alteration in the transcripts encoding histone subtypes and important players in chromatin remodeling was observed. The mRNAs which transcribe neurotransmitters such as OXT, AVP, PMCH and LNPEP and two small non-coding RNAs, namely RMRP and BC1 were down regulated. At least some of these changes are likely to regulate REMS and may participate in the consequences of REMS loss. Thus, the findings of this study have identified key epigenetic regulators and neuronal plasticity genes associated to REMS and its loss. This analysis provides a background and opens up avenues for unraveling their specific roles in the complex behavioral network particularly in relation to sustained REMS-loss associated changes.
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Affiliation(s)
- Santosh C Narwade
- Molecular Biology Research Laboratory, Center of Advanced Studies, Department of Zoology, Savitribai Phule Pune University Pune, India
| | | | - Deepti D Deobagkar
- Molecular Biology Research Laboratory, Center of Advanced Studies, Department of Zoology, Savitribai Phule Pune UniversityPune, India; Bioinformatics Center, Savitribai Phule Pune UniversityPune, India
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Changes in Body Water Caused by Sleep Deprivation in Taeeum and Soyang Types in Sasang Medicine: Prospective Intervention Study. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2017; 2017:2105343. [PMID: 28676829 PMCID: PMC5476891 DOI: 10.1155/2017/2105343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 04/16/2017] [Accepted: 05/14/2017] [Indexed: 11/18/2022]
Abstract
Background There is a negative relationship between sleep deprivation and health. However, no study has investigated the effect of sleep deprivation on individuals with different body composition. The aim of this study was to determine the differential effect of sleep deprivation in individuals with different body compositions (fluid) according to Soyang type (SY) and Taeeum type (TE). Methods Sixty-two cognitively normal, middle-aged people with normal sleep patterns were recruited from the local population. The duration of participants' sleep was restricted to 4 h/day during the intervention phase. To examine the physiological changes brought on by sleep deprivation and recovery, 10 ml of venous blood was obtained. Results Total Body Water (TBW) and Extracellular Water (ECW) were significantly different between the groups in the intervention phase. Physiological parameters also varied from the beginning of the resting phase to the end of the experiment. Potassium levels changed more in SY than TE individuals. Conclusion Participants responded differently to the same amount of sleep deprivation depending on their Sasang constitution types. This study indicated that SY individuals were more sensitive to sleep deprivation and were slower to recover from the effects of sleep deprivation than TE individuals.
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Mehta R, Singh A, Bókkon I, Nath Mallick B. REM sleep and its Loss-Associated Epigenetic Regulation with Reference to Noradrenaline in Particular. Curr Neuropharmacol 2016; 14:28-40. [PMID: 26813120 PMCID: PMC4787282 DOI: 10.2174/1570159x13666150414185737] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/02/2015] [Accepted: 04/11/2015] [Indexed: 01/12/2023] Open
Abstract
Sleep is an essential physiological process, which has been divided into rapid eye movement sleep (REMS) and non-REMS (NREMS) in higher animals. REMS is a unique phenomenon that unlike other sleep-waking states is not under voluntary control. Directly or indirectly it influences or gets influenced by most of the physiological processes controlled by the brain. It has been proposed that REMS serves housekeeping function of the brain. Extensive research has shown that during REMS at least noradrenaline (NA) -ergic neurons must cease activity and upon REMS loss, there are increased levels of NA in the brain, which then induces many of the REMS loss associated acute and chronic effects. The NA level is controlled by many bio-molecules that are regulated at the molecular and transcriptional levels. Similarly, NA can also directly or indirectly modulate the synthesis and levels of many molecules, which in turn may affect physiological processes. The burgeoning field of behavioral neuroepigenetics has gained importance in recent years and explains the regulatory mechanisms underlying several behavioral phenomena. As REMS and its loss associated changes in NA modulate several pathophysiological processes, in this review we have attempted to explain on one hand how the epigenetic mechanisms regulating the gene expression of factors like tyrosine hydroxylase (TH), monoamine oxidase (MAO), noradrenaline transporter (NAT) control NA levels and on the other hand, how NA per se can affect other molecules in neural circuitry at the epigenetic level resulting in behavioral changes in health and diseases. An
understanding of these events will expose the molecular basis of REMS and its loss-associated pathophysiological changes; which are presented as a testable hypothesis for confirmation.
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Somarajan BI, Khanday MA, Mallick BN. Rapid Eye Movement Sleep Deprivation Induces Neuronal Apoptosis by Noradrenaline Acting on Alpha1 Adrenoceptor and by Triggering Mitochondrial Intrinsic Pathway. Front Neurol 2016; 7:25. [PMID: 27014180 PMCID: PMC4779900 DOI: 10.3389/fneur.2016.00025] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 02/19/2016] [Indexed: 12/13/2022] Open
Abstract
Many neurodegenerative disorders are associated with rapid eye movement sleep (REMS) loss; however, the mechanism was unknown. As REMS loss elevates noradrenaline (NA) level in the brain as well as induces neuronal apoptosis and degeneration, in this study, we have delineated the intracellular molecular pathway involved in REMS deprivation (REMSD)-associated NA-induced neuronal apoptosis. Rats were REMS deprived for 6 days by the classical flower pot method; suitable controls were conducted and the effects on apoptosis markers evaluated. Further, the role of NA was studied by one, intraperitoneal (i.p.) injection of NA-ergic alpha1 adrenoceptor antagonist prazosin (PRZ) and two, by downregulation of NA synthesis in locus coeruleus (LC) neurons by local microinjection of tyrosine hydroxylase siRNA (TH-siRNA). Immunoblot estimates showed that the expressions of proapoptotic proteins viz. Bcl2-associated death promoter protein, apoptotic protease activating factor-1 (Apaf-1), cytochrome c, caspase9, caspase3 were elevated in the REMS-deprived rat brains, while caspase8 level remained unaffected; PRZ treatment did not allow elevation of these proapoptotic factors. Further, REMSD increased cytochrome c expression, which was prevented if the NA synthesis from the LC neurons was blocked by microinjection of TH-siRNA in vivo into the LC during REMSD in freely moving normal rats. Mitochondrial damage was re-confirmed by transmission electron microscopy, which showed distinctly swollen mitochondria with disintegrated cristae, chromosomal condensation, and clumping along the nuclear membrane, and all these changes were prevented in PRZ-treated rats. Combining findings of this study along with earlier reports, we propose that upon REMSD NA level increases in the brain as the LC, NA-ergic REM-OFF neurons do not cease firing and TH is upregulated in those neurons. This elevated NA acting on alpha1 adrenoceptors damages mitochondria causing release of cytochrome c to activate intrinsic pathway for inducing neuronal apoptosis in REMS-deprived rat brain.
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Affiliation(s)
- Bindu I Somarajan
- School of Life Sciences, Jawaharlal Nehru University , New Delhi , India
| | - Mudasir A Khanday
- School of Life Sciences, Jawaharlal Nehru University , New Delhi , India
| | - Birendra N Mallick
- School of Life Sciences, Jawaharlal Nehru University , New Delhi , India
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Rapid Eye Movement Sleep Deprivation Associated Increase in Na-K ATPase Activity in the Rat Brain is Due to Noradrenaline Induced α1-Adrenoceptor Mediated Increased α-Subunit of the Enzyme. Neurochem Res 2015; 40:1747-57. [DOI: 10.1007/s11064-015-1660-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 06/29/2015] [Accepted: 07/01/2015] [Indexed: 10/23/2022]
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Siran R, Ahmad AH, Abdul Aziz CB, Ismail Z. REM sleep deprivation induces changes of Down Regulatory Antagonist Modulator (DREAM) expression in the ventrobasal thalamic nuclei of Sprague–Dawley rats. J Physiol Biochem 2014; 70:877-89. [DOI: 10.1007/s13105-014-0356-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 09/02/2014] [Indexed: 01/24/2023]
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Peters AC, Blechert J, Sämann PG, Eidner I, Czisch M, Spoormaker VI. One night of partial sleep deprivation affects habituation of hypothalamus and skin conductance responses. J Neurophysiol 2014; 112:1267-76. [PMID: 24920020 DOI: 10.1152/jn.00657.2013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Sleep disturbances are prevalent in clinical anxiety, but it remains unclear whether they are cause and/or consequence of this condition. Fear conditioning constitutes a valid laboratory model for the acquisition of normal and pathological anxiety. To explore the relationship between disturbed sleep and anxiety in more detail, the present study evaluated the effect of partial sleep deprivation (SD) on fear conditioning in healthy individuals. The neural correlates of 1) nonassociative learning and physiological processing and 2) associative learning (differential fear conditioning) were addressed. Measurements entailed simultaneous functional MRI, EEG, skin conductance response (SCR), and pulse recordings. Regarding nonassociative learning, partial SD resulted in a generalized failure to habituate during fear conditioning, as evidenced by reduced habituation of SCR and hypothalamus responses to all stimuli. Furthermore, SCR and hypothalamus activity were correlated, supporting their functional relationship. Regarding associative learning, effects of partial SD on the acquisition of conditioned fear were weaker and did not reach statistical significance. The hypothalamus plays an integral role in the regulation of sleep and autonomic arousal. Thus sleep disturbances may play a causal role in the development of normal and possibly pathological fear by increasing the susceptibility of the sympathetic nervous system to stressful experiences.
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Affiliation(s)
- Anja C Peters
- Neuroimaging Research Group, Max Planck Institute of Psychiatry, Munich, Germany; and
| | - Jens Blechert
- Division of Clinical Psychology, Psychotherapy, and Health Psychology, Institute of Psychology, University of Salzburg, Salzburg, Austria
| | - Philipp G Sämann
- Neuroimaging Research Group, Max Planck Institute of Psychiatry, Munich, Germany; and
| | - Ines Eidner
- Neuroimaging Research Group, Max Planck Institute of Psychiatry, Munich, Germany; and
| | - Michael Czisch
- Neuroimaging Research Group, Max Planck Institute of Psychiatry, Munich, Germany; and
| | - Victor I Spoormaker
- Neuroimaging Research Group, Max Planck Institute of Psychiatry, Munich, Germany; and
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Involvement of the α1-adrenoceptor in sleep-waking and sleep loss-induced anxiety behavior in zebrafish. Neuroscience 2013; 245:136-47. [PMID: 23618759 DOI: 10.1016/j.neuroscience.2013.04.026] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 04/10/2013] [Accepted: 04/12/2013] [Indexed: 01/06/2023]
Abstract
Sleep is a universal phenomenon in vertebrates, and its loss affects various behaviors. Independent studies have reported that sleep loss increases anxiety; however, the detailed mechanism is unknown. Because sleep deprivation increases noradrenalin (NA), which modulates many behaviors and induces patho-physiological changes, this study utilized zebrafish as a model to investigate whether sleep loss-induced increased anxiety is modulated by NA. Continuous behavioral quiescence for at least 6s was considered to represent sleep in zebrafish; although some authors termed it as a sleep-like state, in this study we have termed it as sleep. The activity of fish that signified sleep-waking was recorded in light-dark, during continuous dark and light; the latter induced sleep loss in fish. The latency, number of entries, time spent and distance travelled in the light chamber were assessed in a light-dark box test to estimate the anxiety behavior of normal, sleep-deprived and prazosin (PRZ)-treated fish. Zebrafish showed increased waking during light and complete loss of sleep upon continuous exposure to light for 24h. PRZ significantly increased sleep in normal fish. Sleep-deprived fish showed an increased preference for dark (expression of increased anxiety), and this effect was prevented by PRZ, which increased sleep as well. Our findings suggest that sleep loss-induced anxiety-like behavior in zebrafish is likely to be mediated by NA's action on the α1-adrenoceptor.
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Singh S, Amar M, Mallick BN. Rapid eye movement sleep deprivation modulates synapsinI expression in rat brain. Neurosci Lett 2012; 520:62-6. [PMID: 22609569 DOI: 10.1016/j.neulet.2012.05.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2012] [Revised: 04/29/2012] [Accepted: 05/08/2012] [Indexed: 11/17/2022]
Abstract
Rapid eye movement sleep (REMS) deprivation (REMSD) has been reported to elevate neurotransmitter level in the brain; however, intracellular mechanism of its increased release was not studied. Phosphorylation of synapsinI, a synaptic vesicle-associated protein, is involved in the regulation of neurotransmitter release. In this study, rats were REMS deprived by classical flowerpot method; free moving control (FMC), large platform control (LPC) and recovery control (REC) was carried out. In another set REMS deprived rats were intraperitoneally (i.p.) injected with α1-adrenoceptor antagonist, prazosin (PRZ). Effects of REMSD on Na-K ATPase activity and on the total synapsinI as well as phosphorylated synapsinI levels were estimated in synaptosomes prepared from whole brain. It was observed that REMSD significantly increased synaptosomal Na-K ATPase activity, which was prevented by PRZ. Western blotting of the same samples by anti-synapsinI and anti-synapsinI-phosphoSer603 showed that REMSD increased both the total as well as phospho-form of synapsinI as compared to respective levels in FMC and LPC samples. These findings suggest a functional link between REMSD and synaptic vesicular mobilization at the presynaptic terminal, a process that is essential for neurotransmitter release. The findings help explaining the intracellular mechanism of elevated neurotransmitter release associated to REMSD.
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Affiliation(s)
- Sudhuman Singh
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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Activation of inactivation process initiates rapid eye movement sleep. Prog Neurobiol 2012; 97:259-76. [PMID: 22521402 DOI: 10.1016/j.pneurobio.2012.04.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 04/01/2012] [Accepted: 04/02/2012] [Indexed: 02/07/2023]
Abstract
Interactions among REM-ON and REM-OFF neurons form the basic scaffold for rapid eye movement sleep (REMS) regulation; however, precise mechanism of their activation and cessation, respectively, was unclear. Locus coeruleus (LC) noradrenalin (NA)-ergic neurons are REM-OFF type and receive GABA-ergic inputs among others. GABA acts postsynaptically on the NA-ergic REM-OFF neurons in the LC and presynaptically on the latter's projection terminals and modulates NA-release on the REM-ON neurons. Normally during wakefulness and non-REMS continuous release of NA from the REM-OFF neurons, which however, is reduced during the latter phase, inhibits the REM-ON neurons and prevents REMS. At this stage GABA from substantia nigra pars reticulate acting presynaptically on NA-ergic terminals on REM-ON neurons withdraws NA-release causing the REM-ON neurons to escape inhibition and being active, may be even momentarily. A working-model showing neurochemical-map explaining activation of inactivation process, showing contribution of GABA-ergic presynaptic inhibition in withdrawing NA-release and dis-inhibition induced activation of REM-ON neurons, which in turn activates other GABA-ergic neurons and shutting-off REM-OFF neurons for the initiation of REMS-generation has been explained. Our model satisfactorily explains yet unexplained puzzles (i) why normally REMS does not appear during waking, rather, appears following non-REMS; (ii) why cessation of LC-NA-ergic-REM-OFF neurons is essential for REMS-generation; (iii) factor(s) which does not allow cessation of REM-OFF neurons causes REMS-loss; (iv) the association of changes in levels of GABA and NA in the brain during REMS and its deprivation and associated symptoms; v) why often dreams are associated with REMS.
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REM sleep loss increases brain excitability: role of noradrenaline and its mechanism of action. Sleep Med Rev 2011; 15:165-78. [PMID: 21482157 DOI: 10.1016/j.smrv.2010.11.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 10/24/2010] [Accepted: 11/02/2010] [Indexed: 01/12/2023]
Abstract
Ever since the discovery of rapid eye movement sleep (REMS), studies have been undertaken to understand its necessity, function and mechanism of action on normal physiological processes as well as in pathological conditions. In this review, first, we briefly surveyed the literature which led us to hypothesise REMS maintains brain excitability. Thereafter, we present evidence from in vivo and in vitro studies tracing behavioural to cellular to molecular pathways showing REMS deprivation (REMSD) increases noradrenaline level in the brain, which stimulates neuronal Na-K ATPase, the key factor for maintaining neuronal excitability, the fundamental property of a neuron for executing brain functions; we also show for the first time the role of glia in maintaining ionic homeostasis in the brain. As REMSD exerts a global effect on most of the physiological processes regulated by the brain, we propose that REMS possibly serves a housekeeping function in the brain. Finally, subject to confirmation from clinical studies, based on the results reviewed here, it is being proposed that the subjects suffering from REMS loss may be effectively treated by reducing either noradrenaline level or Na-K ATPase activity in the brain.
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Ranjan A, Biswas S, Mallick BN. Cytomorphometric changes in the dorsal raphe neurons after rapid eye movement sleep deprivation are mediated by noradrenalin in rats. BEHAVIORAL AND BRAIN FUNCTIONS : BBF 2010; 6:62. [PMID: 20964843 PMCID: PMC2984478 DOI: 10.1186/1744-9081-6-62] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Accepted: 10/21/2010] [Indexed: 11/18/2022]
Abstract
OBJECTIVES This study was carried out to investigate the effect of rapid eye movement sleep (REMS) deprivation (REMSD) on the cytomorphology of the dorsal raphe (DR) neurons and to evaluate the possible role of REMSD-induced increased noradrenalin (NA) in mediating such effects. METHODS Rats were REMS deprived by the flowerpot method; free moving normal home cage rats, large platform and post REMS-deprived recovered rats were used as controls. Further, to evaluate if the effects were induced by NA, separate sets of experimental rats were treated (i.p.) with α1-adrenoceptor antagonist, prazosin (PRZ). Histomorphometric analysis of DR neurons in stained brain sections were performed in experimental and control rats; neurons in inferior colliculus (IC) served as anatomical control. RESULTS The mean size of DR neurons was larger in REMSD group compared to controls, whereas, neurons in the recovered group of rats did not significantly differ than those in the control animals. Further, mean cell size in the post-REMSD PRZ-treated animals was comparable to those in the control groups. IC neurons were not affected by REMSD. CONCLUSIONS REMS loss has been reported to impair several physiological, behavioral and cellular processes. The mean size of the DR neurons was larger in the REMS deprived group of rats than those in the control groups; however, in the REMS deprived and prazosin treated rats the size was comparable to the normal rats. These results showed that REMSD induced increase in DR neuronal size was mediated by NA acting on α1-adrenoceptor. The findings suggest that the sizes of DR neurons are sensitive to REMSD, which if not compensated could lead to neurodegeneration and associated disorders including memory loss and Alzheimer's disease.
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Affiliation(s)
- Amit Ranjan
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Sudipta Biswas
- Current address: Behavioral Neuroscience Division, Dept. of Psychology, Arizona State University, Tempe, AZ 85287-1104, USA
| | - Birendra N Mallick
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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Mechanism of noradrenaline-induced stimulation of Na–K ATPase activity in the rat brain: implications on REM sleep deprivation-induced increase in brain excitability. Mol Cell Biochem 2009; 336:3-16. [DOI: 10.1007/s11010-009-0260-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2009] [Accepted: 09/15/2009] [Indexed: 10/20/2022]
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23
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Jaiswal MK, Mallick BN. Prazosin modulates rapid eye movement sleep deprivation-induced changes in body temperature in rats. J Sleep Res 2009; 18:349-56. [PMID: 19552734 DOI: 10.1111/j.1365-2869.2008.00731.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Prolonged rapid eye movement sleep deprivation (REMSD) causes hypothermia and death; however, the effect of deprivation within 24 h and its mechanism(s) of action were unknown. Based on existing reports we argued that REMSD should, at least initially, induce hyperthermia and the death upon prolonged deprivation could be due to persistent hypothermia. We proposed that noradrenaline (NA), which modulates body temperature and is increased upon REMSD, may be involved in REMSD- associated body temperature changes. Adult male Wistar rats were REM sleep deprived for 6-9 days by the classical flower pot method; suitable free moving, large platform and recovery controls were carried out. The rectal temperature (Trec) was recorded every minute for 1 h, or once daily, or before and after i.p. injection of prazosin, an alpha-1 adrenergic antagonist. The Trec was indeed elevated within 24 h of REMSD which decreased steadily, despite continuation of deprivation. Prazosin injection into the deprived rats reduced the Trec within 30 min, and the duration of effect was comparable to its pharmacological half life. The findings have been explained on the basis of REMSD-induced elevated NA level, which has opposite actions on the peripheral and the central nervous systems. We propose that REMSD-associated immediate increase in Trec is due to increased Na-K ATPase as well as metabolic activities and peripheral vasoconstriction. However, upon prolonged deprivation, probably the persistent effect of NA on the central thermoregulatory sites induced sustained hypothermia, which if remained uncontrolled, results in death. Thus, our findings suggest that peripheral prazosin injection in REMSD would not bring the body temperature to normal, rather might become counterproductive.
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Affiliation(s)
- Manoj K Jaiswal
- School of Life Sciences, Jawaharlal Nehru University, New Delhi-110067, India
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24
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Baskey G, Singh A, Sharma R, Mallick BN. REM sleep deprivation-induced noradrenaline stimulates neuronal and inhibits glial Na–K ATPase in rat brain: In vivo and in vitro studies. Neurochem Int 2009; 54:65-71. [DOI: 10.1016/j.neuint.2008.10.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Revised: 10/14/2008] [Accepted: 10/20/2008] [Indexed: 11/28/2022]
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Das G, Gopalakrishnan A, Faisal M, Mallick B. Stimulatory role of calcium in rapid eye movement sleep deprivation–induced noradrenaline-mediated increase in Na-K-ATPase activity in rat brain. Neuroscience 2008; 155:76-89. [DOI: 10.1016/j.neuroscience.2008.04.069] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Revised: 03/07/2008] [Accepted: 04/28/2008] [Indexed: 11/16/2022]
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26
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Effect of paradoxical sleep deprivation on oxidative stress parameters in brain regions of adult and old rats. Biogerontology 2008; 9:153-62. [DOI: 10.1007/s10522-008-9124-z] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Accepted: 01/05/2008] [Indexed: 10/22/2022]
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27
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Noradrenaline acting on α1-adrenoceptor mediates REM sleep deprivation-induced increased membrane potential in rat brain synaptosomes. Neurochem Int 2008; 52:734-40. [DOI: 10.1016/j.neuint.2007.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2007] [Revised: 09/01/2007] [Accepted: 09/05/2007] [Indexed: 11/21/2022]
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28
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Biswas S, Mishra P, Mallick BN. Increased apoptosis in rat brain after rapid eye movement sleep loss. Neuroscience 2006; 142:315-31. [PMID: 16887278 DOI: 10.1016/j.neuroscience.2006.06.026] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2006] [Revised: 06/15/2006] [Accepted: 06/16/2006] [Indexed: 01/12/2023]
Abstract
Rapid eye movement (REM) sleep loss impairs several physiological, behavioral and cellular processes; however, the mechanism of action was unknown. To understand the effects of REM sleep deprivation on neuronal damage and apoptosis, studies were conducted using multiple apoptosis markers in control and experimental rat brain neurons located in areas either related to or unrelated to REM sleep regulation. Furthermore, the effects of REM sleep deprivation were also studied on neuronal cytoskeletal proteins, actin and tubulin. It was observed that after REM sleep deprivation a significantly increased number of neurons in the rat brain were positive to apoptotic markers, which however, tended to recover after the rats were allowed to undergo REM sleep; the control rats were not affected. Further, it was also observed that REM sleep deprivation decreased amounts of actin and tubulin in neurons confirming our previous reports of changes in neuronal size and shape after such deprivation. These findings suggest that one of the possible functions of REM sleep is to protect neurons from damage and apoptosis.
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Affiliation(s)
- S Biswas
- School of Life Sciences, Jawaharlal Nehru University, Baba Gang Nath Marg, New Delhi 110067, India
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Pal D, Mallick BN. Role of noradrenergic and GABA-ergic inputs in pedunculopontine tegmentum for regulation of rapid eye movement sleep in rats. Neuropharmacology 2006; 51:1-11. [PMID: 16616214 DOI: 10.1016/j.neuropharm.2006.02.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2005] [Revised: 02/10/2006] [Accepted: 02/13/2006] [Indexed: 01/12/2023]
Abstract
Rapid eye movement (REM) sleep disturbance is associated with several psycho-behavioral disorders, hence, it is important to understand its neural mechanism of regulation. Although it was known that the noradrenergic (NA-ergic) neurons from locus coeruleus (LC) project to the pedunculopontine tegmentum (PPT), the role of noradrenaline (NA) alone and in association with GABA, an inhibitory neurotransmitter, in PPT for REM sleep regulation was not known and was investigated in this study in freely moving normally behaving rats. Rats were surgically prepared for electrophysiological sleep-wake recording and simultaneous bilateral microinjections into PPT. 200nl of prazosin (alpha1-antagonist) or clonidine (alpha2-agonist) or propranolol (beta-antagonist) or combination of picrotoxin (GABA-A antagonist) and clonidine or vehicle (control) was microinjected bilaterally into PPT using a remote-controlled pump and the effects on REM sleep compared. Prazosin, clonidine and propranolol increased the total time spent in REM sleep whereas co-injection of picrotoxin and clonidine did not affect REM sleep. The results suggest that NA in PPT tonically inhibits REM sleep, possibly by acting on the cholinergic REM-ON neurons, while GABA inhibits the release of NA for REM sleep regulation. A model of neural connections explaining such regulation has been presented.
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Affiliation(s)
- Dinesh Pal
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110 067, India
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Mallick BN, Singh S, Pal D. Role of alpha and beta adrenoceptors in locus coeruleus stimulation-induced reduction in rapid eye movement sleep in freely moving rats. Behav Brain Res 2005; 158:9-21. [PMID: 15680190 DOI: 10.1016/j.bbr.2004.08.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2004] [Revised: 07/28/2004] [Accepted: 08/05/2004] [Indexed: 11/21/2022]
Abstract
Based on the results of independent studies the involvement of norepinephrine in REM sleep regulation was known. Isolated studies showed that the effect could be mediated through either one or more subtypes of adrenoceptors. Earlier we have reported that REM-OFF neurons continue firing during REM sleep deprivation and mild but continuous stimulation of locus coeruleus (LC) or picrotoxin injection into the LC, that did not allow the REM-OFF neurons in the LC to stop firing, reduced REM sleep. However, the mechanism of action and type of adrenoreceptors involved in REM sleep regulation were unknown. The possible mechanism of action has been investigated in this study. It was proposed that if LC stimulation-induced decrease in REM sleep was due to norepinephrine, adrenergic antagonist must prevent the effect. Therefore, in this study, the effects of alpha1, alpha2 and beta-antagonists, viz. prazosin, yohimbine and propranolol, respectively, and alpha2 agonist, clonidine, on LC stimulation-induced reduction in REM sleep were investigated. The results showed that stimulation of LC inhibited REM sleep by reducing the frequency of generation of REM sleep, although the duration per episode remained unaffected. This decrease in the frequency of REM sleep was blocked by beta-antagonist propranolol while the duration of REM sleep per episode was blocked by alpha1-antagonist, prazosin. Also, a critical level of norepinephrine in the system was required for the generation of REM sleep, however, a higher level may be inhibitory. Based on the results of this study and our earlier studies, an interaction between neurons, containing different neurotransmitters and their subtypes of receptors for LC-mediated regulation of REM sleep has been proposed.
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Affiliation(s)
- Birendra N Mallick
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110 067, India.
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31
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Pal D, Mallick BN. GABA in pedunculo pontine tegmentum regulates spontaneous rapid eye movement sleep by acting on GABAA receptors in freely moving rats. Neurosci Lett 2004; 365:200-4. [PMID: 15246548 DOI: 10.1016/j.neulet.2004.04.080] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2004] [Revised: 04/19/2004] [Accepted: 04/29/2004] [Indexed: 11/17/2022]
Abstract
REM-OFF and REM-ON neurons in the brainstem are reported to regulate REM sleep, however, the detailed mechanism of generation of REM sleep is unknown. The former are continuously active except during REM sleep and an inhibitory neurotransmitter, GABA, has been implicated in mediating the inhibition for the generation of REM sleep. The REM-ON neurons, on the other hand, remain inactive throughout but increase firing during REM sleep. This study was conducted to investigate if GABA in the brain area rich in cholinergic REM-ON neurons would modulate REM sleep as proposed earlier. Rats were surgically prepared for sleep-wake recording and two cannulae aiming pedunculopontine areas in the brainstem that are rich in REM-ON neurons, were implanted bilaterally. After recovery, picrotoxin, a GABA(A) antagonist, was simultaneously microinjected bilaterally into the pedunculopontine area in freely moving normally behaving rats using a remote dual syringe pump and the effects were studied on electrophysiological sleep and waking parameters. The results showed that picrotoxin significantly reduced REM sleep for 6h and the effect was due to reduction in the frequency of generation of REM sleep.
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Affiliation(s)
- Dinesh Pal
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110 067, India
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Majumdar S, Faisal M, Madan V, Mallick BN. Increased turnover of Na-K ATPase molecules in rat brain after rapid eye movement sleep deprivation. J Neurosci Res 2003; 73:870-5. [PMID: 12949914 DOI: 10.1002/jnr.10710] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
It has been shown that rapid eye movement (REM) sleep deprivation increases Na-K ATPase activity. Based on kinetic study, it was proposed that increased activity was due to enhanced turnover of enzyme molecules. To test this, anti-alpha1 Na-K ATPase monoclonal antibody (mAb 9A7) was used to label Na-K ATPase molecules. These labeled enzymes were quantified on neuronal membrane by two methods: histochemically on neurons in tissue sections from different brain areas, and by Western blot analysis in control and REM sleep-deprived rat brains. The specific enzyme activity was also estimated and found to be increased, as in previous studies. The results confirmed our hypothesis that after REM sleep deprivation, increased Na-K ATPase activity was at least partly due to increased turnover of Na-K ATPase molecules in the rat brain.
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Affiliation(s)
- Sudipta Majumdar
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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33
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Majumdar S, Mallick BN. Increased levels of tyrosine hydroxylase and glutamic acid decarboxylase in locus coeruleus neurons after rapid eye movement sleep deprivation in rats. Neurosci Lett 2003; 338:193-6. [PMID: 12581829 DOI: 10.1016/s0304-3940(02)01404-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Norepinephrine, acetylcholine and GABA levels alter during rapid eye movement (REM) sleep and its deprivation. Increased synthesis of those neurotransmitters is necessary for their sustained release. Hence, in this study, the concentrations of tyrosine hydroxylase (TH), choline acetyl transferase (ChAT) and glutamic acid decarboxylase (GAD), the enzymes responsible for their synthesis, were immunohistochemically estimated within the neurons in locus coeruleus, laterodorsal tegmentum and pedunculopontine tegmentum and medial preoptic area in REM sleep deprived and control rats. It was observed that as compared to controls, deprivation increased TH and GAD significantly in the locus coeruleus only, while in other areas, they remained unchanged. The findings help explaining the mechanism of increase in neurotransmitter levels in the brain after REM sleep deprivation and their significance has been discussed.
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Affiliation(s)
- S Majumdar
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110 067, India
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Mallick BN, Majumdar S, Faisal M, Yadav V, Madan V, Pal D. Role of norepinephrine in the regulation of rapid eye movement sleep. J Biosci 2002; 27:539-51. [PMID: 12381879 DOI: 10.1007/bf02705052] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sleep and wakefulness are instinctive behaviours that are present across the animal species. Rapid eye movement (REM) sleep is a unique biological phenomenon expressed during sleep. It evolved about 300 million years ago and is noticed in the more evolved animal species. Although it has been objectively identified in its present characteristic form about half a century ago, the mechanics of how REM is generated, and what happens upon its loss are not known. Nevertheless, extensive research has shown that norepinephrine plays a crucial role in its regulation. The present knowledge that has been reviewed in this manuscript suggests that neurons in the brain stem are responsible for controlling this state and presence of excess norepinephrine in the brain does not allow its generation. Furthermore, REM sleep loss increases levels of norepinephrine in the brain that affects several factors including an increase in Na-K ATPase activity. It has been argued that such increased norepinephrine is ultimately responsible for REM sleep deprivation, associated disturbances in at least some of the physiological conditions leading to alteration in behavioural expression and settling into pathological conditions.
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Affiliation(s)
- Birendra N Mallick
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110 067, India.
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35
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Shram N, Netchiporouk L, Cespuglio R. Lactate in the brain of the freely moving rat: voltammetric monitoring of the changes related to the sleep-wake states. Eur J Neurosci 2002; 16:461-6. [PMID: 12193189 DOI: 10.1046/j.1460-9568.2002.02081.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cortical lactate was monitored voltammetrically in freely moving rats equipped with polygraphic electrodes. Differential normal pulse voltammetric measurements were carried out using a lactate biosensor coated with lactate oxidase and cellulose acetate. Changes occurring in lactate level were in keeping with sleep-wake states. During slow wave sleep (SWS), the lactate level decreased significantly (-16.2%) vs. the spontaneous waking state (W) referenced to as 100%. During paradoxical sleep (PS), and still vs. W, it remained low (-9.0%) but this variation was not statistically significant. However, when this PS change was compared to the SWS variation, a significant increase in lactate level was then revealed (+8.5%). Finally, during the active waking (aW) triggered by a water puff stress, lactate level rose significantly in accordance with the animal activity (+53% compared to W). Long-term monitoring also allowed the determination of a circadian component in lactate production, the lowest and highest values being monitored during light and dark periods, respectively. The acrophasis of the circadian change occurred during the dark period, about 3 h after the light-off (+89%). It is suggested that during wakefulness astrocyte metabolism allows the transformation of the blood-borne glucose into lactate. The increase in this substrate observed during PS may fulfil the oxidative phosphorylation in order to supply the important ATP need of PS.
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Affiliation(s)
- Nataliya Shram
- INSERM Unit 480, Claude Bernard University, 8 av. Rockefeller, 69373 Lyon cedex 08, France
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36
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Mallick BN, Adya HV, Faisal M. Norepinephrine-stimulated increase in Na+, K+-ATPase activity in the rat brain is mediated through alpha1A-adrenoceptor possibly by dephosphorylation of the enzyme. J Neurochem 2000; 74:1574-8. [PMID: 10737614 DOI: 10.1046/j.1471-4159.2000.0741574.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Rapid eye movement sleep deprivation is reported to increase Na+,K+-ATPase activity. This increase was shown earlier to be stimulated by norepinephrine acting on alpha1-adrenoceptor. The involvement of a subtype of alpha1-adrenoceptor and the possible molecular mechanism of action of norepinephrine in increasing the enzyme activity were investigated using receptor agonists and antagonists, as well as stimulants and blockers of signal transduction pathway. It was observed that incubation of the homogenate with cyclic AMP, forskolin, A23187 (a calcium ionophore), or calmodulin alone did not stimulate the Na+,K+-ATPase activity. However, although the spontaneous activity of the Na+,K+-ATPase was not affected by prazosin, WB4101, heparin, W13, or cyclosporin A alone, each of them could prevent the norepinephrine-stimulated increase in the enzyme activity. Based on these results and our previous findings, it is proposed that norepinephrine acted on alpha1A-adrenoceptor and increased intracellular calcium, which in the presence of calmodulin activated a calmodulin-dependent phosphatase, calcineurin. This calcineurin possibly dephosphorylated Na+,K+-ATPase and increased its activity. The physiological significance especially in relation to rapid eye movement sleep deprivation is discussed.
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Affiliation(s)
- B N Mallick
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.
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37
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Adya HV, Mallick BN. Uncompetitive stimulation of rat brain Na-K ATPase activity by rapid eye movement sleep deprivation. Neurochem Int 2000; 36:249-53. [PMID: 10676860 DOI: 10.1016/s0197-0186(99)00121-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Rapid eye movement sleep deprivation is associated with an increase in Na-K ATPase activity. In order to understand the possible biochemical mechanism of this increase, the kinetics of Na-K ATPase was studied. Although the enzyme activity increased after the deprivation, the catalytic efficiency of the enzyme remained unaltered. The rapid eye movement sleep deprivation increased both the Vmax and the Km suggesting an uncompetitive stimulation of the enzyme. While increase in norepinephrine resulted in an increased Vmax, that of calcium increased the Km. Since an increase in norepinephrine has been suggested after deprivation, the increased Vmax is attributed to increased norepinephrine level following deprivation. However, since rapid eye movement sleep deprivation is reported to be associated with a decrease in calcium levels, the increase in Km following deprivation may be attributed to changes in factor(s) other than calcium.
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Affiliation(s)
- H V Adya
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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38
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Gottesmann C. The neurophysiology of sleep and waking: intracerebral connections, functioning and ascending influences of the medulla oblongata. Prog Neurobiol 1999; 59:1-54. [PMID: 10416960 DOI: 10.1016/s0301-0082(98)00094-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This paper focuses on the successive historical papers related to medulla oblongata (M.O.) intracerebral connections, its activities and ascending influences regulating sleep waking behavior. The M.O. certainly influences the quantitative and qualitative processes of waking. However, its neurophysiological properties are often concealed by those of the upper-situated brain stem structures. The M.O., particularly the solitary tract nucleus, is involved in sleep-inducing processes. This nucleus seem to act as a deactivating system of the above situated reticular formation, but it also impacts directly on the thalamocortical slow wave and spindle-inducing processes. The M.O. is significantly involved in paradoxical sleep mechanisms. Indeed, the mesopontine executive centers are unable to induce paradoxical sleep without the M.O. Moreover, stimulation of the solitary tract nucleus afferents can induce paradoxical sleep, and the M.O. metabolic functioning is specifically disturbed by paradoxical sleep deprivation. Finally. there seems to be a paradoxical sleep Zeitgeber. Our current knowledge shows that this lowest brain stem level is crucial for sleep waking mechanisms. It will undoubtedly be further highlighted by future electrophysiologial and neurochemical studies.
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Affiliation(s)
- C Gottesmann
- Laboratoire de Psychophysiologie, Faculté des Sciences, Université de Nice-Sophia Antipolis, Nice, France.
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39
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Mallick BN, Adya HV. Norepinephrine induced alpha-adrenoceptor mediated increase in rat brain Na-K ATPase activity is dependent on calcium ion. Neurochem Int 1999; 34:499-507. [PMID: 10402225 DOI: 10.1016/s0197-0186(99)00025-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
It has been reported that norepinephrine increases Na-K ATPase activity by acting on alpha-1 adrenoceptors. The mechanism of such an increase was investigated. The norepinephrine induced increase in synaptosomal Na-K ATPase activity was prevented by pretreating the rat brain homogenate with either EDTA, a divalent cation chelator or prazosin, an alpha-1 adrenoceptor blocker. The norepinephrine and EGTA increased the Na-K ATPase activity in the synaptosome prepared from rat brain homogenate untreated with EDTA. The EGTA was ineffective in stimulating the enzyme activity if the synaptosome was prepared from homogenate treated with norepinephrine. However, the EGTA was effective in increasing the enzyme activity if the synaptosome was prepared from the homogenate treated with norepinephrine in the presence of prazosin. Thus, norepinephrine did not increase the Na-K ATPase activity in the presence of EDTA or alpha-1 adrenoceptor blocker. Similarly, the Ca++ chelator, EGTA, could not increase the enzyme activity if the homogenate was pretreated with norepinephrine alone. However, if norepinephrine action was blocked by alpha-1 antagonist prazosin, EGTA increased the enzyme activity possibly by chelation of Ca++. Further, chlorotetracycline fluorescence study showed that norepinephrine removes membrane bound Ca++. Thus, it is likely that norepinephrine acts on adrenoceptors and removes membrane bound Ca++ and thereby increases the Na-K ATPase activity in the synaptosome.
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Affiliation(s)
- B N Mallick
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.
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40
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Anupama Adya HV, Mallick BN. Comparison of Na-K ATPase activity in rat brain synaptosome under various conditions. Neurochem Int 1998; 33:283-6. [PMID: 9840218 DOI: 10.1016/s0197-0186(98)00043-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Rapid eye movement (REM) sleep deprivation alters neuronal excitability possibly by increasing Na-K ATPase activity. The enzyme activity is known to be affected by norepinephrine as well as calcium (Ca++) and both are affected by REM sleep deprivation. Before studying its molecular mechanism of action, synaptosomal Na-K ATPase activity was estimated under various conditions. The enzyme activity in synaptosome increased after lysis and in the presence of EDTA. The increase in the lysed preparation was possibly because almost all the active sites of the enzyme molecules were exposed to express their activity, unlike unlysed preparation where half are likely to be inside out. EDTA possibly increased the enzyme activity by chelating the Ca++ which is known to have an inhibitory effect on the enzyme activity. Also, the REM sleep deprivation induced increase in the enzyme activity was observed in lysed preparations and in the presence of EDTA only. These observations fit with the existing knowledge, however, the molecular mechanism of the increase needs to be investigated.
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Affiliation(s)
- H V Anupama Adya
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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41
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Mallick BN, Gulyani S. Alterations in synaptosomal calcium concentrations after rapid eye movement sleep deprivation in rats. Neuroscience 1996; 75:729-36. [PMID: 8951869 DOI: 10.1016/0306-4522(96)00177-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Rapid eye movement sleep deprivation alters behavioral and physiological, as well as cellular functioning and responsiveness. Since intracellular calcium concentration plays an important role in regulating cellular functions, it was hypothesized that such deprivation might induce changes in intracellular calcium concentration. Therefore, in this study, rats were deprived of rapid eye movement sleep by the flower-pot technique, and total, bound and free calcium concentrations were estimated in synaptosomal preparations from the cerebrum, cerebellum, brainstem, midbrain, pons and medulla. Rapid eye movement sleep deprivation was continued for two or four days and suitable control experiments were conducted to rule out the effects of non-specific factors. Total calcium concentration increased in the brainstem but showed a decrease in the cerebellum and cerebrum. After four days deprivation, the free calcium concentration always decreased; however, the bound calcium concentration decreased in the cerebrum and cerebellum but increased in the brainstem. After two days' deprivation, the medulla was the only region where the bound calcium increased while the free form decreased; only the free form decreased in the pons, while the midbrain was never affected. The results suggest that there was a net efflux of calcium in the cerebellum and cerebrum, but a net influx in the brainstem. The findings support our hypothesis and help to explain earlier observations. Since it is known that calcium plays an important role in cellular functioning, these changes in calcium concentration may be the underlying mechanism for rapid eye movement sleep deprivation-induced cellular expressions and behavior of neurons.
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Affiliation(s)
- B N Mallick
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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42
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Singh S, Mallick BN. Mild electrical stimulation of pontine tegmentum around locus coeruleus reduces rapid eye movement sleep in rats. Neurosci Res 1996; 24:227-35. [PMID: 8815443 DOI: 10.1016/0168-0102(95)00998-1] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The norepinephrinergic neurons in the locus coeruleus (LC) cease firing during REM sleep (REMS) and increase firing during REMS deprivation. Most of the earlier studies used lesion and transection techniques which could not confirm the role of LC in REMS generation and/or its maintenance, if at all. Hence, in this study it was hypothesized that if the LC REM-off neurons must cease firing before the onset of REMS, its continuous activation should eliminate or at least reduce REMS. Electrophysiological parameters characterizing sleep-wakefulness-REMS were recorded in freely moving male albino rats. In an attempt not to allow the REM-off LC neurons to cease firing, low intensity (200 microA), low frequency (2 Hz) rectangular (300 microseconds) pulses were continuously delivered to the LC bilaterally through chronically implanted electrodes, and the effects on sleep-wakefulness-REMS were investigated. Although the stimulation did not affect sleep state of the animals, it reduced REMS significantly. The effect on REMS was similar to that of REMS deprivation. Total duration of REMS was significantly reduced during stimulation and showed a rebound increase during the post stimulation period. This reduction in REMS duration was primarily due to a significant reduction in the REMS frequency/h while the mean REMS duration/episode was not affected. Thus, the results of this study suggest that the stimulated area (LC) affects REMS, most likely by suppression of REMS generation process.
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Affiliation(s)
- S Singh
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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