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Mathé AA, Michaneck M, Berg E, Charney DS, Murrough JW. A Randomized Controlled Trial of Intranasal Neuropeptide Y in Patients With Major Depressive Disorder. Int J Neuropsychopharmacol 2020; 23:783-790. [PMID: 33009815 PMCID: PMC7770516 DOI: 10.1093/ijnp/pyaa054] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 07/03/2020] [Accepted: 07/23/2020] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Since about one-third of patients with major depressive disorder (MDD) do not respond adequately to available antidepressants, there is a need for treatments based on novel mechanisms of action. Neuropeptide Y (NPY), a normal brain constituent, is reduced in cerebrospinal fluid of patients with MDD and post-traumatic stress disorder and in corresponding rodent models. Moreover, NPY administered centrally or intranasally rescues pathophysiology in these models. Consequently, we conducted the first, to our knowledge, controlled trial of NPY as a treatment for MDD. METHODS Thirty MDD patients on a stable dose of a conventional antidepressant insufflated 6.8 mg NPY (n = 12) or placebo (n = 18) in a double blind randomized fashion. Effects were assessed at baseline, +1 hour, +5 hours, +24 hours, and +48 hours. The primary outcome was change in depression severity measured with the Montgomery-Åsberg Depression Rating Scale (MADRS). RESULTS NPY was superior to placebo at +24 hours (change -10.3 [95% CI: -13.8; -6.8]) vs -5.6 (95% CI: -8.4; -2.7); group*time F = 3.26, DF = (1,28), P = .04; Cohen's d = 0.67). At +5 hours MADRS decreased -7.1 ([95% CI: -10.0; -4.2] vs -3.5 [95% CI: -5.8; -1.2]; group*time F = 2.69, DF = (1,28), P = .05; Cohen's d = 0.61). MADRS reduction at +48 hours was not significant. CONCLUSIONS Since no results regarding the trajectory of NPY effects existed prior to this study we extrapolated from the known NPY biology and predicted the effects will occur 5-48 hours post insufflation. We chose +48 hours as the primary endpoint and +1, +5, and +24 hours as secondary endpoints. The results, the first of their kind, indicate that insufflated NPY is antidepressant, despite not meeting the primary outcome, and call for dose ranging and repeated NPY insufflation trials. CLINICAL TRIAL REGISTRATION EudraCT Number: 2014-000129-19.
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Affiliation(s)
- Aleksander A Mathé
- Center for Psychiatric Research, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden,Correspondence: Aleksander Mathé, MD, PhD, Department of Clinical Neuroscience, Tomtebodavägen 18A Karolinska Institutet, 17176 Stockholm, Sweden ()
| | - Miranda Michaneck
- Center for Psychiatric Research, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Elisabeth Berg
- Center for Psychiatric Research, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Dennis S Charney
- Office of the Dean, Icahn School of Medicine at Mount Sinai, New York, New York,Depression and Anxiety Center for Discovery and Treatment, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - James W Murrough
- Depression and Anxiety Center for Discovery and Treatment, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York
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Fogaça MV, Duman RS. Cortical GABAergic Dysfunction in Stress and Depression: New Insights for Therapeutic Interventions. Front Cell Neurosci 2019. [PMID: 30914923 DOI: 10.3389/fncel.2019.00087/full] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Major depressive disorder (MDD) is a debilitating illness characterized by neuroanatomical and functional alterations in limbic structures, notably the prefrontal cortex (PFC), that can be precipitated by exposure to chronic stress. For decades, the monoaminergic deficit hypothesis of depression provided the conceptual framework to understand the pathophysiology of MDD. However, accumulating evidence suggests that MDD and chronic stress are associated with an imbalance of excitation-inhibition (E:I) within the PFC, generated by a deficit of inhibitory synaptic transmission onto principal glutamatergic neurons. MDD patients and chronically stressed animals show a reduction in GABA and GAD67 levels in the brain, decreased expression of GABAergic interneuron markers, and alterations in GABAA and GABAB receptor levels. Moreover, genetically modified animals with deletion of specific GABA receptors subunits or interneuron function show depressive-like behaviors. Here, we provide further evidence supporting the role of cortical GABAergic interneurons, mainly somatostatin- and parvalbumin-expressing cells, required for the optimal E:I balance in the PFC and discuss how the malfunction of these cells can result in depression-related behaviors. Finally, considering the relatively low efficacy of current available medications, we review new fast-acting pharmacological approaches that target the GABAergic system to treat MDD. We conclude that deficits in cortical inhibitory neurotransmission and interneuron function resulting from chronic stress exposure can compromise the integrity of neurocircuits and result in the development of MDD and other stress-related disorders. Drugs that can establish a new E:I balance in the PFC by targeting the glutamatergic and GABAergic systems show promising as fast-acting antidepressants and represent breakthrough strategies for the treatment of depression.
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Affiliation(s)
- Manoela V Fogaça
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Ronald S Duman
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
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Fogaça MV, Duman RS. Cortical GABAergic Dysfunction in Stress and Depression: New Insights for Therapeutic Interventions. Front Cell Neurosci 2019; 13:87. [PMID: 30914923 PMCID: PMC6422907 DOI: 10.3389/fncel.2019.00087] [Citation(s) in RCA: 191] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 02/20/2019] [Indexed: 12/14/2022] Open
Abstract
Major depressive disorder (MDD) is a debilitating illness characterized by neuroanatomical and functional alterations in limbic structures, notably the prefrontal cortex (PFC), that can be precipitated by exposure to chronic stress. For decades, the monoaminergic deficit hypothesis of depression provided the conceptual framework to understand the pathophysiology of MDD. However, accumulating evidence suggests that MDD and chronic stress are associated with an imbalance of excitation-inhibition (E:I) within the PFC, generated by a deficit of inhibitory synaptic transmission onto principal glutamatergic neurons. MDD patients and chronically stressed animals show a reduction in GABA and GAD67 levels in the brain, decreased expression of GABAergic interneuron markers, and alterations in GABAA and GABAB receptor levels. Moreover, genetically modified animals with deletion of specific GABA receptors subunits or interneuron function show depressive-like behaviors. Here, we provide further evidence supporting the role of cortical GABAergic interneurons, mainly somatostatin- and parvalbumin-expressing cells, required for the optimal E:I balance in the PFC and discuss how the malfunction of these cells can result in depression-related behaviors. Finally, considering the relatively low efficacy of current available medications, we review new fast-acting pharmacological approaches that target the GABAergic system to treat MDD. We conclude that deficits in cortical inhibitory neurotransmission and interneuron function resulting from chronic stress exposure can compromise the integrity of neurocircuits and result in the development of MDD and other stress-related disorders. Drugs that can establish a new E:I balance in the PFC by targeting the glutamatergic and GABAergic systems show promising as fast-acting antidepressants and represent breakthrough strategies for the treatment of depression.
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Affiliation(s)
- Manoela V Fogaça
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Ronald S Duman
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
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4
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Sayed S, Van Dam NT, Horn SR, Kautz MM, Parides M, Costi S, Collins KA, Iacoviello B, Iosifescu DV, Mathé AA, Southwick SM, Feder A, Charney DS, Murrough JW. A Randomized Dose-Ranging Study of Neuropeptide Y in Patients with Posttraumatic Stress Disorder. Int J Neuropsychopharmacol 2017; 21:3-11. [PMID: 29186416 PMCID: PMC5795352 DOI: 10.1093/ijnp/pyx109] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 11/17/2017] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Anxiety and trauma-related disorders are among the most prevalent and disabling medical conditions in the United States, and posttraumatic stress disorder in particular exacts a tremendous public health toll. We examined the tolerability and anxiolytic efficacy of neuropeptide Y administered via an intranasal route in patients with posttraumatic stress disorder. METHODS Twenty-six individuals were randomized in a cross-over, single ascending dose study into 1 of 5 cohorts: 1.4 mg (n=3), 2.8 mg (n=6), 4.6 mg (n=5), 6.8 mg (n=6), and 9.6 mg (n=6). Each individual was dosed with neuropeptide Y or placebo on separate treatment days 1 week apart in random order under double-blind conditions. Assessments were conducted at baseline and following a trauma script symptom provocation procedure subsequent to dosing. Occurrence of adverse events represented the primary tolerability outcome. The difference between treatment conditions on anxiety as measured by the Beck Anxiety Inventory and the State-Trait Anxiety Inventory immediately following the trauma script represented efficacy outcomes. RESULTS Twenty-four individuals completed both treatment days. Neuropeptide Y was well tolerated up to and including the highest dose. There was a significant interaction between treatment and dose; higher doses of neuropeptide Y were associated with a greater treatment effect, favoring neuropeptide Y over placebo on Beck Anxiety Inventory score (F1,20=4.95, P=.038). There was no significant interaction for State-Trait Anxiety Inventory score. CONCLUSIONS Our study suggests that a single dose of neuropeptide Y is well tolerated up to 9.6 mg and may be associated with anxiolytic effects. Future studies exploring the safety and efficacy of neuropeptide Y in stress-related disorders are warranted. The reported study is registered at: http://clinicaltrials.gov (ID: NCT01533519).
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Affiliation(s)
- Sehrish Sayed
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Nicholas T Van Dam
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Sarah R Horn
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Marin M Kautz
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Michael Parides
- Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Sara Costi
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Katherine A Collins
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Brian Iacoviello
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York,Click Therapeutics, Inc., New York, New York
| | - Dan V Iosifescu
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York,New York University School of Medicine, New York, New York,Nathan Kline Institute for Psychiatric Research, Orangeburg, New York
| | - Aleksander A Mathé
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Steven M Southwick
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut,National Center for PTSD, VA CT Healthcare System, New Haven, Connecticut
| | - Adriana Feder
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Dennis S Charney
- Office of the Dean, Icahn School of Medicine at Mount Sinai, New York, New York
| | - James W Murrough
- Mood and Anxiety Disorders Program, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York,Correspondence: James W. Murrough, MD, Mood and Anxiety Disorders Research Program. Department of Psychiatry, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1230, New York, NY 10029 ()
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Sabban EL, Alaluf LG, Serova LI. Potential of neuropeptide Y for preventing or treating post-traumatic stress disorder. Neuropeptides 2016; 56:19-24. [PMID: 26617395 DOI: 10.1016/j.npep.2015.11.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 11/11/2015] [Accepted: 11/11/2015] [Indexed: 10/22/2022]
Abstract
There is extensive evidence that NPY in the brain can modulate the responses to stress and play a critical role in resistance to, or recovery from, harmful effects of stress. Development of PTSD and comorbid depression following exposure to traumatic stress are associated with low NPY. This review discusses putative mechanisms for NPY's anti-stress actions. Recent preclinical data indicating potential for intranasal delivery of NPY to brain as a promising non-invasive strategy to prevent a variety of neuroendocrine, molecular and behavioral impairments in PTSD model are summarized.
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Affiliation(s)
- Esther L Sabban
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States.
| | - Lishay G Alaluf
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States
| | - Lidia I Serova
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY 10595, United States
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Enman NM, Sabban EL, McGonigle P, Van Bockstaele EJ. Targeting the Neuropeptide Y System in Stress-related Psychiatric Disorders. Neurobiol Stress 2015; 1:33-43. [PMID: 25506604 PMCID: PMC4260418 DOI: 10.1016/j.ynstr.2014.09.007] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Repeated, extreme, or traumatic stressors can elicit pathological effects leading to many negative physical and psychological outcomes. Stressors can precipitate the onset of psychiatric diseases, or exacerbate pre-existing disorders including various anxiety and mood disorders. As stressors can negatively impact human psychiatric health, it is essential to identify neurochemicals that may confer protection from the negative sequelae of repeated or extreme stress exposure. Elucidating the neurobiological underpinnings of stress resilience will enhance our ability to promote resilience to, or recovery from, stress-related psychiatric disease. Herein, we will review the evidence for neuropeptide Y as an endogenous mediator of resilience and its potential relevance for the treatment of stress-related psychiatric diseases. Overview of neuropeptide Y and receptor subtypes in the central nervous system. Alterations of neuropeptide Y in human stress-related psychiatric disorders. Evidence for neuropeptide Y in resilience to stress-related emotionality in rodent behavioral models. Pharmacotherapeutic implications for neuropeptide Y in the treatment of stress-related psychiatric disorders.
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Affiliation(s)
- Nicole M Enman
- Department of Pharmacology and Physiology, Drexel University, Philadelphia, PA, 19102, USA
| | - Esther L Sabban
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY, 10595, USA
| | - Paul McGonigle
- Department of Pharmacology and Physiology, Drexel University, Philadelphia, PA, 19102, USA
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Effects of intranasal hypocretin-1 (orexin A) on sleep in narcolepsy with cataplexy. Sleep Med 2011; 12:941-6. [PMID: 22036605 DOI: 10.1016/j.sleep.2011.06.015] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 06/17/2011] [Accepted: 06/29/2011] [Indexed: 01/11/2023]
Abstract
BACKGROUND The neuropeptides hypocretin-1 and -2 (hcrt-1 and -2, also known as orexin A and B) are crucially involved in the regulation of sleep/wake states. On the one hand, the sleep-wake disorder narcolepsy can be caused by an hcrt-1 deficiency. On the other, intracerebral administration of hcrt-1 produces an increase in wakefulness at the expense of REM sleep in normal and narcoleptic animals. In humans intranasal administration has been shown to effectively deliver neuropeptides directly to the central nervous system. We hypothesised that the intranasal application of hcrt-1 increases wakefulness and reduces REM sleep in the natural human hcrt-1 deficiency narcolepsy with cataplexy. METHODS In this double-blind, random-order crossover, placebo-controlled, within-subject design study we administered human recombinant hcrt-1 (435 nmol) intranasally to eight subjects with narcolepsy with cataplexy before night sleep, followed by standard polysomnography. RESULTS Although intranasal administration of hcrt-1 had no statistically significant effect on nocturnal wakefulness, we found that it reduced REM sleep quantity, particularly during the second half of the recording. Furthermore, intranasal hcrt-1 had a clear REM sleep stabilising effect and led to significantly reduced direct wake to REM transitions. CONCLUSION In this pilot study we found, first, evidence that the intranasal administration of hcrt-1 has functional effects on sleep in narcolepsy with cataplexy. Our results may encourage the use of the intranasal approach in further studies on hypocretinergic sleep regulation and might also contribute to the future development of a causal treatment for narcolepsy with cataplexy.
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Booth JN, Koren SA, Persinger MA. INCREASED FEELINGS OF THE SENSED PRESENCE AND INCREASED GEOMAGNETIC ACTIVITY AT THE TIME OF THE EXPERIENCE DURING EXPOSURES TO TRANSCEREBRAL WEAK COMPLEX MAGNETIC FIELDS. Int J Neurosci 2009; 115:1053-79. [PMID: 16051550 DOI: 10.1080/00207450590901521] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In 2 separate experiments involving 39 subjects the incidence of sensing a presence or Sentient Being while being exposed to weak complex magnetic fields over the right hemisphere was moderately correlated with increased global geomagnetic activity during the 3-h periods of the experiences. Analyses of magnetometer values near the laboratory indicated the intensity of the east-west component of the geomagnetic field had been increasing consistently at about 1 pT/s for at least 10 min for a cumulative change of about 15 to 20 nT. The ratios of the durations of alpha rhythms over the temporal lobes compared to the occipital lobes were correlated significantly with both increased geomagnetic activity and the reports of a presence. Removal of the shared variance between the sensed presence and various psychometric inferences of temporal lobe sensitivity and the history of dissociation increased and decreased, respectively, the strength of the partial correlations between geomagnetic activity and the reports of a sensed presence. The results suggest the culturally and historically ubiquitous phenomena of sensed presences are generated by right hemispheric processes that once enhanced by a variety of stimuli, including weak complex magnetic fields, can be encouraged by increased global geomagnetic activity.
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Affiliation(s)
- J N Booth
- Behavioral Neursocience Laboratory, Laurentian University, Sudbury, Ontario, Canada
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Baier PC, Weinhold SL, Huth V, Gottwald B, Ferstl R, Hinze-Selch D. Olfactory dysfunction in patients with narcolepsy with cataplexy is restored by intranasal Orexin A (Hypocretin-1). Brain 2008; 131:2734-41. [PMID: 18718966 DOI: 10.1093/brain/awn193] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Until recently, olfactory dysfunction was an unknown feature of narcolepsy. Orexin A, also called hypocretin-1, is abnormally decreased or undetectable in the cerebrospinal fluid of narcoleptic patients with cataplexies. As hypothalamic orexin-containing neurons project throughout the entire olfactory pathway, from the olfactory mucosa to the olfactory cortex, disturbed orexinergic transmission may crucially be involved in impaired olfactory performance of narcolepsy patients. In our study we analysed the olfactory performance (threshold, discrimination, identification and sum score of these measurements, the TDI score) of narcoleptic patients with cataplexies (n = 10) and of age-, gender-, BMI- and smoker/non-smoker-matched healthy controls (n = 10). We then in a double-blind, randomized, placebo-controlled cross-over design applied orexin A intranasally to seven of the patients and measured 2-phenyl-ethyl alcohol (PEA) single-staircase odour detection thresholds. Compared to the controls, patients showed significantly lower scores for olfactory threshold (patients: median 8.0, range 4.0-10.5; controls: median 9.4, range 7.5-13.3; P < 0.05), discrimination (patients: median 12.5, range 10-15; controls: median 15.0, range 12-16; P < 0.005), identification (patients: median 13.0, range 10-16; controls: median 14.0, range 13-16; P < 0.05) and TDI score (patients: median 33.4, range 30-36; controls: median 38.4, range 35-43; P < 0.0001). In all patients, the PEA olfactory threshold score increased after administration of orexin A (median 11.5, range 6.5-13.25) compared to placebo (median 7.75, range 6.25-11.25; P < 0.05). Our results support the hypothesis that mild olfactory dysfunction is an intrinsic symptom of narcolepsy with cataplexies. The observation that intranasal orexin A restores olfactory function is in favour of this hypothesis. Furthermore, our data support that the pathophysiological mechanism underlying olfactory dysfunction in narcolepsy is the lack of CNS orexin.
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Affiliation(s)
- Paul Christian Baier
- Department of Psychiatry and Psychotherapy, Christian-Albrechts University Kiel, Kiel, Germany.
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Haus E. Chronobiology in the endocrine system. Adv Drug Deliv Rev 2007; 59:985-1014. [PMID: 17804113 DOI: 10.1016/j.addr.2007.01.001] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Accepted: 01/15/2007] [Indexed: 12/13/2022]
Abstract
Biological signaling occurs in a complex web with participation and interaction of the central nervous system, the autonomous nervous system, the endocrine glands, peripheral endocrine tissues including the intestinal tract and adipose tissue, and the immune system. All of these show an intricate time structure with rhythms and pulsatile variations in multiple frequencies. Circadian (about 24-hour) and circannual (about 1-year) rhythms are kept in step with the cyclic environmental surrounding by the timing and length of the daily light span. Rhythmicity of many endocrine variables is essential for their efficacy and, even in some instances, for the qualitative nature of their effects. Indeed, the continuous administration of certain hormones and their synthetic analogues may show substantially different effects than expected. In the design of drug-delivery systems and treatment schedules involving directly or indirectly the endocrine system, consideration of the human time organization is essential. A large amount of information on the endocrine time structure has accumulated, some of which is discussed in this review.
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Affiliation(s)
- Erhard Haus
- Department of Laboratory Medicine and Pathology, University of Minnesota, Health Partners Medical Group, Regions Hospital, 640 Jackson Street, St. Paul, Minnesota 55101, USA.
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Kiris IGA, Eroldoğan OT, Kir M, Kumlu M. Influence of neuropeptide Y (NPY) on food intake and growth of penaeid shrimps Marsupenaeus japonicus and Penaeus semisulcatus (Decapoda: Penaeidae). Comp Biochem Physiol A Mol Integr Physiol 2005; 139:239-44. [PMID: 15528173 DOI: 10.1016/j.cbpb.2004.09.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Revised: 09/13/2004] [Accepted: 09/14/2004] [Indexed: 11/16/2022]
Abstract
The effects of neuropeptide Y (NPY) administered intramuscularly or orally on postlarvae (PLs) of two penaeid species were investigated in this study. In experiment 1, food intake (FI) of Marsupenaeus japonicus PLs (0.96 g), injected with NPY at 0.6 microg per g BW, was investigated within 48 h posttreatment. In experiment 2, oral administration of NPY (at doses of 0, 0.125, 0.25, 0.5 microg g(-1) food) on feed intake and growth performance of Penaeus semisulcatus PLs (0.27 g) was examined for 6 weeks. In experiment 1, NPY injection significantly increased average daily FI of M. japonicus PLs within the first 24 h compared to the control (P<0.05), but its stimulatory effect decreased on the second day (P>0.05). The increase in FI was 33% during the first 24 h and 17% during the next 24 h. In experiment 2, significant (P<0.05) differences were found among the groups in terms of weight gain and food utilization (P<0.05). Mean FI significantly increased (as much as 1.3-fold over the control) when NPY was orally administered at doses from 0.125 to 0.5 microg g(-1) feed. There was a positive relationship between FI and final weight (y=-0.972+2.098x, R(2)=0.81) and between FCE and NPY doses in the diets (y=45.37+3.46x, R(2)=0.91). The present findings indicated for the first time that NPY is a potent stimulator of food intake when administered either intramuscularly or orally to penaeid shrimps.
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Affiliation(s)
- I G A Kiris
- Faculty of Fisheries, Department of Aquaculture, Cukurova University, 01330, Balcali, Adana, Turkey
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