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Chen L, Yue Z, Liu Z, Liu H, Zhang J, Zhang F, Hu T, Fu J. The impact of Nrf2 knockout on the neuroprotective effects of dexmedetomidine in a mice model of cognitive impairment. Behav Brain Res 2024; 469:115006. [PMID: 38692357 DOI: 10.1016/j.bbr.2024.115006] [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: 12/17/2023] [Revised: 04/08/2024] [Accepted: 04/19/2024] [Indexed: 05/03/2024]
Abstract
The nuclear factor erythroid 2-related factor 2 (Nrf2) signalling pathway represents a crucial intrinsic protective system against oxidative stress and inflammation and plays a significant role in various neurological disorders. However, the effect of Nrf2 signalling on the regulation of cognitive impairment remains unknown. Dexmedetomidine (DEX) has neuroprotective effects and can ameliorate lipopolysaccharide (LPS)-induced cognitive dysfunction. Our objective was to observe whether Nrf2 knockout influences the efficacy of DEX in improving cognitive impairment and to attempt to understand its underlying mechanisms. An LPS-induced cognitive dysfunction model in wild-type and Nrf2 knockout mice (Institute of Cancer Research background; male; 8-12 weeks) was used to observe the impact of DEX on cognitive dysfunction. LPS was intraperitoneally injected, followed by novel object recognition and morris water maze experiments 24 h later. Hippocampal tissues were collected for histopathological and molecular analyses. Our research findings suggest that DEX enhances the expression of NQO1, HO-1, PSD95, and SYP proteins in hippocampal tissue, inhibits microglial proliferation, reduces pro-inflammatory cytokines IL-1β and TNF-ɑ, increases anti-inflammatory cytokine IL-10, and improves dendritic spine density, thereby alleviating cognitive dysfunction induced by LPS. However, the knockout of the Nrf2 gene negated the aforementioned effects of DEX. In conclusion, DEX alleviates cognitive deficits induced by LPS through mechanisms of anti-oxidative stress and anti-inflammation, as well as by increasing synaptic protein expression and dendritic spine density. However, the knockout of the Nrf2 gene reversed the effects of DEX. The Nrf2 signaling pathway plays a crucial role in the mitigation of LPS-induced cognitive impairment by DEX.
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Affiliation(s)
- Liang Chen
- Department of Anesthesiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China; Department of Anesthesiology, Shijiazhuang Fourth Hospital, Shijiazhuang, China
| | - Zhifeng Yue
- Department of Anesthesiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
| | - Ziyu Liu
- Department of Human Anatomy, Institute of Medicine and Health, Hebei Medical University, Shijiazhuang, Hebei, China; The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Huaqin Liu
- Department of Anesthesiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
| | - Jin Zhang
- Department of Anesthesiology, Shijiazhuang Fourth Hospital, Shijiazhuang, China
| | - Fengjiao Zhang
- Department of Anesthesiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
| | - Tao Hu
- Department of Anesthesiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
| | - Jianfeng Fu
- Department of Anesthesiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
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TLR4 Signaling Selectively and Directly Promotes CGRP Release from Vagal Afferents in the Mouse. eNeuro 2021; 8:ENEURO.0254-20.2020. [PMID: 33318075 PMCID: PMC7877464 DOI: 10.1523/eneuro.0254-20.2020] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 12/03/2020] [Accepted: 12/03/2020] [Indexed: 12/14/2022] Open
Abstract
There has been a long-standing debate regarding the role of peripheral afferents in mediating rapid-onset anorexia among other responses elicited by peripheral inflammatory insults. Thus, the current study assessed the sufficiency of peripheral afferents expressing toll-like receptor 4 (TLR4) to the initiation of the anorexia caused by peripheral bacterial lipopolysaccharide (LPS). We generated a Tlr4 null (Tlr4LoxTB) mouse in which Tlr4 expression is globally disrupted by a loxP-flanked transcription blocking (TB) cassette. This novel mouse model allowed us to restore the endogenous TLR4 expression in specific cell types. Using Zp3-Cre and Nav1.8-Cre mice, we produced mice that express TLR4 in all cells (Tlr4LoxTB X Zp3-Cre) and in peripheral afferents (Tlr4LoxTB X Nav1.8-Cre), respectively. We validated the Tlr4LoxTB mice, which were phenotypically identical to previously reported global TLR4 knock-out mice. Contrary to our expectations, the administration of LPS did not cause rapid-onset anorexia in mice with Nav1.8-restricted TLR4. The later result prompted us to identify Tlr4-expressing vagal afferents using in situ hybridization (ISH). In vivo, we found that Tlr4 mRNA was primarily enriched in vagal Nav1.8 afferents located in the jugular ganglion that co-expressed calcitonin gene-related peptide (CGRP). In vitro, the application of LPS to cultured Nav1.8-restricted TLR4 afferents was sufficient to stimulate the release of CGRP. In summary, we demonstrated using a new mouse model that vagally-expressed TLR4 is selectively involved in stimulating the release of CGRP but not in causing anorexia.
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Inflammation-induced behavioral changes is driven by alterations in Nrf2-dependent apoptosis and autophagy in mouse hippocampus: Role of fluoxetine. Cell Signal 2019; 68:109521. [PMID: 31881324 DOI: 10.1016/j.cellsig.2019.109521] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 12/21/2019] [Accepted: 12/21/2019] [Indexed: 12/13/2022]
Abstract
Inflammation has been associated with the progression of many neurological diseases. Peripheral inflammation has also been vaguely linked to depression-like symptoms in animal models, but the underlying pathways that orchestrate inflammation-induced behavioral or molecular changes in the brain are still elusive. We have recently shown that intraperitoneal injections of lipopolysaccharide (LPS) to Swiss albino mice triggers systemic inflammation, leading to an activated immune response along with changes in monoamine levels in the brain. Herein we pinpoint the fundamental pathways linking peripheral inflammation and depression-like behavior in a mouse model, thereby identifying suitable targets of intervention to combat the situation. We show that LPS-induced peripheral inflammation provoked a depression-like behavior in mice and a distinct pro-inflammatory bias in the hippocampus, as evident from increased microglial activation and elevated levels of pro-inflammatory cytokines IL-6 and TNF-α, and activation of NFκB-p65 pathway. Significant alterations in Nrf2-dependent cellular redox status, coupled with altered autophagy and increased apoptosis were noticed in the hippocampus of LPS-exposed mice. We and others have previously shown that, fluoxetine (an anti-depressant) has effective anti-inflammatory and antioxidant properties by virtue of its abilities to regulate NFκB and Nrf2 signaling. We observed that treatment with fluoxetine or the Nrf2 activator tBHQ (tert-butyl hydroquinone), could reverse depression-like-symptoms and mitigate alterations in autophagy and cell death pathways in the hippocampus by activating Nrf2-dependent gene expressions. Taken together, the data suggests that systemic inflammation potentiates Nrf2-dependent changes in cell death and autophagy pathway in the hippocampus, eventually leading to major pathologic sequelae associated with depression. Therefore, targeting Nrf2 could be a novel approach in combatting depression and ameliorating its associated pathogenesis.
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Yeh CH, Hsieh LP, Lin MC, Wei TS, Lin HC, Chang CC, Hsing CH. Dexmedetomidine reduces lipopolysaccharide induced neuroinflammation, sickness behavior, and anhedonia. PLoS One 2018; 13:e0191070. [PMID: 29351316 PMCID: PMC5774758 DOI: 10.1371/journal.pone.0191070] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 12/27/2017] [Indexed: 01/23/2023] Open
Abstract
Background Peripheral innate immune response may induce sickness behavior through activating microglia, excessive cytokines production, and neuroinflammation. Dexmedetomidine (Dex) has anti-inflammatory effect. We investigated the effects of Dex on lipopolysaccharide (LPS)-induced neuroinflammation and sickness behavior in mice. Materials and methods BALB/c mice were intraperitoneally (i.p.) injected with Dex (50 ug/kg) or vehicle. One hour later, the mice were injected (i.p.) with Escherichia coli LPS (0.33 mg/kg) or saline (n = 6 in each group). We analyzed the food and water intake, body weight loss, and sucrose preference of the mice for 24h. We also determined microglia activation and cytokines expression in the brains of the mice. In vitro, we determine cytokines expression in LPS-treated BV-2 microglial cells with or without Dex treatment. Results In the Dex-pretreated mice, LPS-induced sickness behavior (anorexia, weight loss, and social withdrawal) were attenuated and microglial activation was lower than vehicle control. The mRNA expression of TNF-α, MCP-1, indoleamine 2, 3 dioxygenase (IDO), caspase-3, and iNOS were increased in the brain of LPS-challenged mice, which were reduced by Dex but not vehicle. Conclusion Dexmedetomidine diminished LPS-induced neuroinflammation in the mouse brain and modulated the cytokine-associated changes in sickness behavior.
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Affiliation(s)
- Ching-Hua Yeh
- Department of Medicinal Botanicals and Health applications, Da-Yeh University, Changhua, Taiwan
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan
| | - Liang-Po Hsieh
- Department of Medicinal Botanicals and Health applications, Da-Yeh University, Changhua, Taiwan
- Department of Neurology, Cheng Ching General Hospital, Taichung, Taiwan
| | - Ming-Chung Lin
- Department of Anesthesiology, Chi-Mei Medical Center, Tainan, Taiwan
| | - Tsui-Shan Wei
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan
| | - Hui-Ching Lin
- Department and Institute of Physiology, School of Medicine, and Brain Research Center, National Yang-Ming University, Taipei, Taiwan
- Neural Regenerative Medicine/Center for Neurotrauma and Neuroregeneration, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Chia-Cheng Chang
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan
- Department of Anesthesiology, Chi-Mei Medical Center, Tainan, Taiwan
| | - Chung-Hsi Hsing
- Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan
- Department of Anesthesiology, Chi-Mei Medical Center, Tainan, Taiwan
- * E-mail:
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Histone Deacetylase Inhibitor Trichostatin A Ameliorated Endotoxin-Induced Neuroinflammation and Cognitive Dysfunction. Mediators Inflamm 2015; 2015:163140. [PMID: 26273133 PMCID: PMC4530275 DOI: 10.1155/2015/163140] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 03/25/2015] [Accepted: 03/25/2015] [Indexed: 11/19/2022] Open
Abstract
Excessive production of cytokines by microglia may cause cognitive dysfunction and long-lasting behavioral changes. Activating the peripheral innate immune system stimulates cytokine secretion in the central nervous system, which modulates cognitive function. Histone deacetylases (HDACs) modulate cytokine synthesis and release. Trichostatin A (TSA), an HDAC inhibitor, is documented to be anti-inflammatory and neuroprotective. We investigated whether TSA reduces lipopolysaccharide- (LPS-) induced neuroinflammation and cognitive dysfunction. ICR mice were first intraperitoneally (i.p.) injected with vehicle or TSA (0.3 mg/kg). One hour later, they were injected (i.p.) with saline or Escherichia coli LPS (1 mg/kg). We analyzed the food and water intake, body weight loss, and sucrose preference of the injected mice and then determined the microglia activation and inflammatory cytokine expression in the brains of LPS-treated mice and LPS-treated BV-2 microglial cells. In the TSA-pretreated mice, microglial activation was lower, anhedonia did not occur, and LPS-induced cognitive dysfunction (anorexia, weight loss, and social withdrawal) was attenuated. Moreover, mRNA expression of HDAC2, HDAC5, indoleamine 2,3-dioxygenase (IDO), TNF-α, MCP-1, and IL-1β in the brain of LPS-challenged mice and in the LPS-treated BV-2 microglial cells was lower. TSA diminished LPS-induced inflammatory responses in the mouse brain and modulated the cytokine-associated changes in cognitive function, which might be specifically related to reducing HDAC2 and HDAC5 expression.
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Carlton ED, Demas GE, French SS. Leptin, a neuroendocrine mediator of immune responses, inflammation, and sickness behaviors. Horm Behav 2012; 62:272-9. [PMID: 22561456 DOI: 10.1016/j.yhbeh.2012.04.010] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 04/05/2012] [Accepted: 04/18/2012] [Indexed: 01/27/2023]
Abstract
Effective immune responses are coordinated by interactions among the nervous, endocrine, and immune systems. Mounting immune, inflammatory, and sickness responses requires substantial energetic investments, and as such, an organism may need to balance energy allocation to these processes with the energetic demands of other competing physiological systems. The metabolic hormone leptin appears to be mediating trade-offs between the immune system and other physiological systems through its actions on immune cells and the brain. Here we review the evidence in both mammalian and non-mammalian vertebrates that suggests leptin is involved in regulating immune responses, inflammation, and sickness behaviors. Leptin has also been implicated in the regulation of seasonal immune responses, including sickness; however, the precise physiological mechanisms remain unclear. Thus, we discuss recent data in support of leptin as a mediator of seasonal sickness responses and provide a theoretical model that outlines how seasonal cues, leptin, and proinflammatory cytokines may interact to coordinate seasonal immune and sickness responses.
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Affiliation(s)
- Elizabeth D Carlton
- Department of Biology, Program in Neuroscience and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN 47405, USA.
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Cholecystokinin: Role in thermoregulation and other aspects of energetics. Clin Chim Acta 2010; 411:329-35. [DOI: 10.1016/j.cca.2009.12.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 12/15/2009] [Accepted: 12/18/2009] [Indexed: 11/17/2022]
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Weiland TJ, Voudouris NJ, Kent S. CCK2 receptor nullification attenuates lipopolysaccharide-induced sickness behavior. Am J Physiol Regul Integr Comp Physiol 2007; 292:R112-23. [PMID: 16857893 DOI: 10.1152/ajpregu.00156.2006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Systemic infection produces a highly regulated set of responses such as fever, anorexia, adipsia, inactivity, and cachexia, collectively referred to as sickness behavior. Although the expression of sickness behavior requires immune-brain communication, the mechanisms by which peripheral cytokines signal the brain are unclear. Several mechanisms have been proposed for neuroimmune communication, including the interaction of cytokines with peripheral nerves. A critical role has been ascribed to the vagus nerve in mediating sickness behavior after intraperitoneally delivered immune activation, and converging evidence suggests that this communication may involve neurochemical intermediaries afferent and/or efferent to this nerve. Mice lacking functional CCK2/gastrin receptors (CCK2KO) and wild-type (WT) controls were administered LPS (50, 500, or 2,500 μg/kg; serotype 0111:B4; ip). Results indicate a role for CCK2 receptor activation in the initiation and maintenance of LPS-induced sickness behavior. Compared with WT controls, CCK2KO mice were significantly less affected by LPS on measures of body temperature, activity, body weight, and food intake, with the magnitude of effects increasing with increasing LPS dose. Although activation of CCK2 receptors at the level of the vagus nerve cannot be excluded, a possible role for these receptors in nonvagal routes of immune-brain communication is suggested.
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Affiliation(s)
- Tracey J Weiland
- School of Psychological Science, La Trobe University, Bundoora, Victoria, Australia.
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Weiland TJ, Kent S, Voudouris NJ, Shulkes A. The effect of lipopolysaccharide on cholecystokinin in murine plasma and tissue. Peptides 2005; 26:447-55. [PMID: 15652652 DOI: 10.1016/j.peptides.2004.10.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2004] [Revised: 10/07/2004] [Accepted: 10/07/2004] [Indexed: 10/26/2022]
Abstract
Several mechanisms have been proposed for neuroimmune communication supporting sickness behavior (fever, anorexia, inactivity, and cachexia) following infection. We examined the role of cholecystokinin as a neurochemical intermediary of sickness behavior by determining plasma, duodenum, hypothalamus, and brainstem cholecystokinin concentrations 30 and 60 min and 12 h following intraperitoneal lipopolysaccharide (LPS) (0.25 and 2.5 mg/kg). Hypothalamic cholecystokinin was significantly lower in LPS- versus saline-treated mice 30 min (0.25 and 2.5 mg/kg) and 12 h (2.5 mg/kg) post-injection. Plasma cholecystokinin of LPS-treated mice was significantly lower than that of controls 1 and 12 h post-injection, a finding consistent with a non-endocrine action of peripheral cholecystokinin.
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Affiliation(s)
- Tracey J Weiland
- School of Psychological Science, La Trobe University, Bundoora, Vic. 3086, Australia
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Ivanov AI, Kulchitsky VA, Romanovsky AA. Role for the cholecystokinin-A receptor in fever: a study of a mutant rat strain and a pharmacological analysis. J Physiol 2003; 547:941-9. [PMID: 12562931 PMCID: PMC2342735 DOI: 10.1113/jphysiol.2002.033183] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2002] [Accepted: 01/06/2003] [Indexed: 11/08/2022] Open
Abstract
The involvement of the cholecystokinin (CCK)-A receptor in fever was studied. The polyphasic febrile responses to lipopolysaccharide (LPS; 10 microg kg-1, I.V.) were compared between wild-type Long-Evans (LE) rats and the CCK-A-receptor-deficient Otsuka LE Tokushima Fatty (OLETF) rats. The response of the wild-type rats was biphasic, which is typical for LE rats. Phases 1 and 2 of the response of the OLETF rats were similar to those of the LE rats, but the OLETF rats also developed a robust phase 3. This late enhancement of the febrile response could reflect either the absence of the A receptor per se or a secondary trait of the mutant strain. To distinguish between these possibilities, we conducted a pharmacological analysis. We studied whether the normally low phase 3 of LE rats can be enhanced by a CCK-A-receptor antagonist, sodium lorglumide (4.3 microg kg-1 min-1, 120 min, I.V.), and whether the normally high phase 3 of Wistar rats can be attenuated by a CCK-A receptor agonist, sulphated CCK-8 (up to 0.17 microg kg-1 min-1, 120 min, I.V.). The dose of sodium lorglumide used was sufficient to increase food intake (to block satiety), but it did not affect the fever response. In both febrile and afebrile rats, CCK-8 induced dose-dependent skin vasodilatation and decreased body temperature, but it failed to produce any effects specific for phase 3. We conclude that the exaggeration of phase 3 in OLETF rats reflects a secondary trait of this strain and not the lack of the CCK-A receptor per se. None of the three known phases of the febrile response of rats to LPS requires the CCK-A receptor.
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Affiliation(s)
- Andrei I Ivanov
- Trauma Research, St Joseph's Hospital and Medical Center, Phoenix, AZ 85013, USA
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Abstract
Peripheral administration of toxic bacterial products and cytokines have been used to model the immunological, physiological, and behavioral responses to infection, including the anorexia of disease. The vagus nerve is the major neuroanatomic linkage between gut sites exposed to peripheral endotoxins and cytokines and the central nervous system regions that mediate the control of food intake, and thus has been a major research focus of the neurobiological approach to understanding cytokine-induced anorexia. Molecular biological and neurophysiologic evidence demonstrates that peripheral anorectic doses of cytokines and endotoxins elicit significant increases in neural activation at multiple peripheral and central levels of the gut-brain axis and in some cases may modify the neural processing of meal-related gastrointestinal signals that contribute to the negative feedback control of ingestion. However, behavioral studies of the anorectic effects of peripheral cytokines and endotoxins have shown that neither vagal nor splanchnic visceral afferent fibers supplying the gut are necessary for the reduction of food intake in these models. These data do not rule out 1) the potential contribution of supradiaphragmatic vagal afferents or 2) a modulatory role for immune-stimulated gut vagal afferent signals in the expression of cytokine and endotoxin-induced anorexia in the intact organism.
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Affiliation(s)
- Gary J Schwartz
- Edward W. Bourne Behavioral Research Laboratory, Weill Medical College of Cornell University, 21 Bloomingdale Road, White Plains, NY 10605, USA.
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Abstract
Thermoregulatory effects of cholecystokinin (CCK) peptides are reviewed with special emphasis on two types of responses, that is hypothermia or hyperthermia. In rodents exposed to cold a dose-dependent hypothermia has been observed on peripheral injection of CCK probably acting on CCKA receptors. Central microinjection of CCK in rats induced a thermogenic response that could be attenuated by CCKB receptor antagonists, but some authors observed a hypothermia. It is suggested that neuronal CCK may have a specific role in the development of hyperthermia, and endogenous CCK-ergic mechanisms could contribute to the mediation of fever. Possible connections between thermoregulatory and other autonomic functional changes induced by CCK are discussed.
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Affiliation(s)
- Z Szelényi
- Department of Pathophysiology, Faculty of Medicine, University of Pécs, 7624 Pécs, Hungary.
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Abstract
Anorexia is one of the most common symptoms associated with illness and constitutes an adaptive strategy in fighting acute infectious diseases. However, prolonged reduction in food intake and an increase in metabolic rate, as seen in the anorexia-cachexia syndrome, lead to depletion of body fat and protein reserves, thus worsening the organism's condition. Because the central nervous system controls many aspects of food intake, soluble factors known as cytokines that are secreted by immune cells might act on the brain to induce anorexia during disease. This review focuses on the communication pathways from the immune system to the brain that might mediate anorexia during disease. The vagus nerve is a rapid route of communication from the immune system to the brain, as subdiaphragmatic vagotomy attenuates the decrease in food-motivated behavior and c-Fos expression in the central nervous system in response to peripheral administration of the proinflammatory cytokine, interleukin-1beta, or bacterial lipopolysaccharide. At later time points after peripheral lipopolysaccharide administration, interleukin-1 itself acts in the brain to mediate anorexia and is found in the arcuate nucleus of the hypothalamus. The mechanisms by which interleukin-1beta gains access to the brain and the potential role of neuropeptide-Y-containing neurons in the arcuate hypothalamus in mediating anorexia during disease are discussed.
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Affiliation(s)
- J P Konsman
- INSERM Unit 394, François Magendie Institute, Bordeaux, France.
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