1
|
Chhatar S, Lal G. Role of adrenergic receptor signalling in neuroimmune communication. CURRENT RESEARCH IN IMMUNOLOGY 2021; 2:202-217. [PMID: 35492402 PMCID: PMC9040148 DOI: 10.1016/j.crimmu.2021.11.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 11/11/2021] [Accepted: 11/17/2021] [Indexed: 11/17/2022] Open
Abstract
Neuroimmune communication plays a crucial role in maintaining homeostasis and promptly responding to any foreign insults. Sympathetic nerve fibres are innervated into all the lymphoid organs (bone marrow, thymus, spleen, and lymph nodes) and provide a communication link between the central nervous system (CNS) and ongoing immune response in the tissue microenvironment. Neurotransmitters such as catecholamines (epinephrine and norepinephrine) bind to adrenergic receptors present on most immune and non-immune cells, establish a local neuroimmune-communication system, and help regulate the ongoing immune response. The activation of these receptors varies with the type of receptor-activated, target cell, the activation status of the cells, and timing of activation. Activating adrenergic receptors, specifically β-adrenergic signalling in immune cells leads to activation of the cAMP-PKA pathway or other non-canonical pathways. It predominantly leads to immune suppression such as inhibition of IL-2 secretion and a decrease in macrophages phagocytosis. This review discusses the expression of different adrenergic receptors in various immune cells, signalling, and how it modulates immune cell function and contributes to health and diseases. Understanding the neuroimmune communication through adrenergic receptor signalling in immune cells could help to design better strategies to control inflammation and autoimmunity. Primary and secondary lymphoid organs are innervated with sympathetic nerve fibres. Adrenergic receptor expression on immune and non-immune cells establishes a local neuroimmune communication system. Adrenergic receptor signalling in immune cells controls the differentiation and function of various immune cells. Modulating adrenergic receptor signalling with a specific agonist or antagonist also affect the immune response.
Collapse
Affiliation(s)
| | - Girdhari Lal
- Corresponding author. National Centre for Cell Science, NCCS Complex, Ganeshkhind, Pune, MH-411007, India.
| |
Collapse
|
2
|
Scanzano A, Cosentino M. Adrenergic regulation of innate immunity: a review. Front Pharmacol 2015; 6:171. [PMID: 26321956 PMCID: PMC4534859 DOI: 10.3389/fphar.2015.00171] [Citation(s) in RCA: 219] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 07/31/2015] [Indexed: 12/24/2022] Open
Abstract
The sympathetic nervous system has a major role in the brain-immune cross-talk, but few information exist on the sympathoadrenergic regulation of innate immune system. The aim of this review is to summarize available knowledge regarding the sympathetic modulation of the innate immune response, providing a rational background for the possible repurposing of adrenergic drugs as immunomodulating agents. The cells of immune system express adrenoceptors (AR), which represent the target for noradrenaline and adrenaline. In human neutrophils, adrenaline and noradrenaline inhibit migration, CD11b/CD18 expression, and oxidative metabolism, possibly through β-AR, although the role of α1- and α2-AR requires further investigation. Natural Killer express β-AR, which are usually inhibitory. Monocytes express β-AR and their activation is usually antiinflammatory. On murine Dentritic cells (DC), β-AR mediate sympathetic influence on DC-T cells interactions. In human DC β2-AR may affect Th1/2 differentiation of CD4+ T cells. In microglia and in astrocytes, β2-AR dysregulation may contribute to neuroinflammation in autoimmune and neurodegenerative disease. In conclusion, extensive evidence supports a critical role for adrenergic mechanisms in the regulation of innate immunity, in peripheral tissues as well as in the CNS. Sympathoadrenergic pathways in the innate immune system may represent novel antiinflammatory and immunomodulating targets with significant therapeutic potential.
Collapse
Affiliation(s)
- Angela Scanzano
- Center for Research in Medical Pharmacology, University of Insubria Varese, Italy
| | - Marco Cosentino
- Center for Research in Medical Pharmacology, University of Insubria Varese, Italy
| |
Collapse
|
3
|
Yang C, Gao W, Yang X, Wang H, Du J, Zhong H, Zhou L, Zhou J, Zhang Y, Jiang J. CRH knockout inhibits the murine innate immune responses in association with endoplasmic reticulum stress after thermal injury. Surgery 2015; 158:255-65. [DOI: 10.1016/j.surg.2015.01.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 12/18/2014] [Accepted: 01/29/2015] [Indexed: 01/07/2023]
|
4
|
O'Neill ASG, van den Berg TK, Mullen GED. Sialoadhesin - a macrophage-restricted marker of immunoregulation and inflammation. Immunology 2013. [PMID: 23181380 DOI: 10.1111/imm.12042] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Sialoadhesin (Sn, also known as Siglec-1 and CD169) is a macrophage-restricted cell surface receptor that is conserved across mammals. Sn is a member of the sialic acid-binding IgG-like lectin (Siglec) family of proteins characterized by affinity to specifically sialylated ligands, and under normal conditions is expressed on subsets of macrophages in secondary lymphoid tissues, such as lymph node and spleen. However, Sn-positive macrophages can also be found in a variety of pathological conditions, including (autoimmune) inflammatory infiltrates and tumours. Sn has been shown to contribute to sialylated pathogen uptake, antigen presentation and lymphocyte proliferation, and to influence both immunity and tolerance. This review presents Sn as a macrophage-specific marker of inflammation and immunoregulation with the potential to becoming an important biomarker for immunologically active macrophages and a target for therapy.
Collapse
Affiliation(s)
- Alexander S G O'Neill
- Division of Imaging Sciences, King's College London, St Thomas' Hospital, London, UK.
| | | | | |
Collapse
|
5
|
Mao YF, Zhang YL, Yu QH, Jiang YH, Wang XW, Yao Y, Huang JL. Chronic restraint stress aggravated arthritic joint swell of rats through regulating nitric oxide production. Nitric Oxide 2012; 27:137-42. [DOI: 10.1016/j.niox.2012.06.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 06/14/2012] [Accepted: 06/16/2012] [Indexed: 12/22/2022]
|
6
|
Liou JT, Yuan HB, Mao CC, Lai YS, Day YJ. Absence of C-C motif chemokine ligand 5 in mice leads to decreased local macrophage recruitment and behavioral hypersensitivity in a murine neuropathic pain model. Pain 2012; 153:1283-1291. [PMID: 22494919 DOI: 10.1016/j.pain.2012.03.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 02/23/2012] [Accepted: 03/07/2012] [Indexed: 10/28/2022]
Abstract
Accumulated evidence suggests that the C-C motif chemokine ligand 5 (CCL5) modulates migration of inflammatory cells in several pathological conditions. This study tested the hypothesis that lack of CCL5 would modulate the recruitment of inflammatory cells to painful, inflamed sites and could attenuate pain in a murine chronic neuropathic pain model. Nociceptive sensitization, immune cell infiltration, multiple cytokine expression, and opioid peptide expression in damaged nerves were studied in wild-type (CCL5 +/+) and CCL5-deficient (CCL5 -/-) mice after partial sciatic nerve ligation (PSNL). Results indicated that CCL5 -/- mice had less behavioral hypersensitivity after PSNL. Macrophage infiltration and proinflammatory cytokines (tumor necrosis factor-α, interleukin [IL]-1β, IL-6, and interferon-γ) in damaged nerves following PSNL were significantly decreased in CCL5 -/- mice. Conversely, several antiinflammatory cytokine (IL-4 and IL-10) proteins were significantly increased in CCL5 -/- animals and the expression of enkephalin, β-endorphin, and dynorphin mRNA was significantly lower than in wild-type control mice. These results represent the first evidence that CCL5 is capable of regulating the pathway that controls hyperalgesia at the level of the peripheral injured site in a murine chronic neuropathic pain model. We demonstrated that lack of CCL5 modulated cell infiltration and the proinflammatory milieu within the injured nerve. Attenuated behavioral hypersensitivity in CCL5 -/- mice observed in the current study could be a result of decreased macrophage infiltration, mobilization, and functional ability at injured sites. Collectively, the present study results suggest that CCL5 receptor antagonists may ultimately provide a novel class of analgesics for therapeutic intervention in chronic neuropathic pain.
Collapse
Affiliation(s)
- Jiin-Tarng Liou
- Department of Anesthesiology, Chang Gung Memorial Hospital, Linkou, Taiwan, ROC Transgenic & Molecular Immunogenetics Laboratory, Chang Gung Memorial Hospital, Linkou, Taiwan, ROC Graduate Institutes of Clinical Medical Sciences, Chang Gung University, Linkou, Taiwan, ROC Department of Anesthesiology, Taipei-Veterans General Hospital and School of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC Department of Medicine, Chang Gung University, Linkou, Taiwan, ROC
| | | | | | | | | |
Collapse
|
7
|
Marino F, Cosentino M. Adrenergic modulation of immune cells: an update. Amino Acids 2011; 45:55-71. [PMID: 22160285 DOI: 10.1007/s00726-011-1186-6] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 11/23/2011] [Indexed: 12/25/2022]
Abstract
Sympathoadrenergic pathways are crucial to the communication between the nervous system and the immune system. The present review addresses emerging issues in the adrenergic modulation of immune cells, including: the specific pattern of adrenoceptor expression on immune cells and their role and changes upon cell differentiation and activation; the production and utilization of noradrenaline and adrenaline by immune cells themselves; the dysregulation of adrenergic immune mechanisms in disease and their potential as novel therapeutic targets. A wide array of sympathoadrenergic therapeutics is currently used for non-immune indications, and could represent an attractive source of non-conventional immunomodulating agents.
Collapse
Affiliation(s)
- Franca Marino
- Department of Clinical Medicine, Section of Experimental and Clinical Pharmacology, University of Insubria, Via Ottorino Rossi n. 9, 21100 Varese, VA, Italy
| | | |
Collapse
|
8
|
Yang C, Yan J, Wang HY, Zhou LL, Zhou JY, Wang ZG, Jiang JX. Effects of bilateral adrenalectomy on the innate immune responses following trauma in rats. Injury 2011; 42:905-12. [PMID: 22081818 DOI: 10.1016/j.injury.2010.02.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND The regulation of neuroendocrine hormones on the innate immune responses in trauma has not been fully understood. Previous studies have shown that the neuroendocrine hormones are important factors in their effects on immune parameters, depending on their concentration and timing instead of the simple suppressive effects. MATERIALS AND METHODS A total of 144 Sprague–Dawley rats were divided randomly into sham, pulmonary blast injury (BI) and adrenalectomy plus pulmonary BI groups. Bilateral adrenalectomy was performed on rats, which were then subjected to blast injury. Following this, peripheral leucocyte responsiveness to lipopolysaccharide (LPS) stimulation, phagocytosis activities of macrophages and bacteria translocation (BT) were examined. Tumour necrosis factor-a (TNF-a) levels and the expression levels of scavenger receptor (SR) A, CD14, Toll-like receptor (TLR) 4 and MD2 were assayed with enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction, respectively. RESULTS In adrenalectomised rats after pulmonary BI, the number of peripheral leucocytes was increased and the phagocytosis of peritoneal and splenic macrophages was decreased as compared to the BI group. Simultaneously, the gut-derived BT and TNF-a secretion in lung tissues were elevated, whilst the LPS-stimulated TNF-a synthesis by peripheral leucocyte responsiveness was reduced. Furthermore, the mRNA levels of SR-A, CD14, TLR4 and MD2 in lung tissues of adrenalectomised rats decreased. Adrenalectomised rats showed enhancement of inflammatory responses and severe tissue injuries in trauma. CONCLUSIONS Release of adrenal hormones might enhance, rather than inhibit, the innate immune functions, particularly in the early stages of trauma.
Collapse
Affiliation(s)
- Ce Yang
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Changjiang Zhilu, Daping, Chongqing, China
| | | | | | | | | | | | | |
Collapse
|
9
|
Sud R, Spengler RN, Nader ND, Ignatowski TA. Antinociception occurs with a reversal in alpha 2-adrenoceptor regulation of TNF production by peripheral monocytes/macrophages from pro- to anti-inflammatory. Eur J Pharmacol 2008; 588:217-31. [PMID: 18514187 DOI: 10.1016/j.ejphar.2008.04.043] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Revised: 04/02/2008] [Accepted: 04/09/2008] [Indexed: 02/07/2023]
Abstract
Tumor necrosis factor-alpha (TNF) plays a role in neuropathic pain. During neuropathic pain development in the chronic constriction injury model, elevated TNF levels in the brain occur in association with enhanced alpha 2-adrenoceptor inhibition of norepinephrine release. alpha 2-Adrenoceptors are also located on peripheral macrophage where they normally function as pro-inflammatory, since they increase the production of the cytokine TNF, a proximal mediator of inflammation. How the central increase in TNF affects peripheral alpha 2-adrenoceptor function was investigated. Male, Sprague-Dawley rats had four loose ligatures placed around the right sciatic nerve. Thermal hyperalgesia was determined by comparing hind paw withdrawal latencies between chronic constriction injury and sham-operated rats. Chronic constriction injury increased TNF immunoreactivity at the lesion and the hippocampus. Amitriptyline, an antidepressant that is used as an analgesic, was intraperitoneally administered (10 mg/kg) starting simultaneous with ligature placement (day-0) or at days-4 or -6 post-surgery. Amitriptyline treatment initiated at day-0 or day-4 post-ligature placement alleviated hyperalgesia. When initiated at day-0, amitriptyline prevented increased TNF immunoreactivity in the hippocampus and at the lesion. A peripheral inflammatory response, macrophage production of TNF, was also assessed in the current study. Lipopolysaccharide (LPS)-stimulated production of TNF by whole blood cells and peritoneal macrophages was determined following activation of the alpha 2-adrenoceptor in vitro. alpha 2-Adrenoceptor regulation of TNF production from peripheral immune-effector cells reversed from potentiation in controls to inhibition in chronic constriction injured rats. This effect is accelerated with amitriptyline treatment initiated at day-0 or day-4 post-ligature placement. Amitriptyline treatment initiated day-6 post-ligature placement did not alleviate hyperalgesia and prevented the switch from potentiation to inhibition in alpha 2-adrenoceptor regulation of TNF production. Recombinant rat TNF i.c.v. microinfusion reproduces the response of peripheral macrophages from rats with chronic constriction injury. A reversal in peripheral alpha 2-adrenoceptor regulation of TNF production from pro- to anti-inflammatory is associated with effective alleviation of thermal hyperalgesia. Thus, alpha 2-adrenoceptor regulation of peripheral TNF production may serve as a potential biomarker to evaluate therapeutic regimens.
Collapse
Affiliation(s)
- Reeteka Sud
- Department of Pathology and Anatomical Sciences, School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14214, USA
| | | | | | | |
Collapse
|
10
|
Elenkov IJ. Effects of Catecholamines on the Immune Response. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s1567-7443(07)00210-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
|
11
|
Haerter K, Vroon A, Kavelaars A, Heijnen CJ, Limmroth V, Espinosa E, Schedlowski M, Elsenbruch S. In vitro adrenergic modulation of cellular immune functions in experimental autoimmune encephalomyelitis. J Neuroimmunol 2004; 146:126-32. [PMID: 14698854 DOI: 10.1016/j.jneuroim.2003.10.051] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To analyze the effects in vitro of alpha- and beta-adrenoceptor agonists on splenocyte proliferation and on proinflammatory cytokine production in splenocytes and peritoneal macrophages (MF) in different stages of EAE. METHODS Splenocytes and peritoneal macrophages were harvested in the acute phase of EAE and in remission, and from controls. The beta-agonist terbutaline, the alpha(1)-agonist methoxamine, and the alpha(2)-agonist UK-14304 were added with ConA or lipopolysaccharide (LPS). TNF-alpha and IFN-gamma contents in supernatant and splenocyte proliferation were determined. RESULTS Terbutaline and UK-14304 significantly suppressed TNF-alpha production by MF. However, EAE acute phase rats were resistant to the suppressive effect of UK-14304. Terbutaline significantly suppressed IFN-gamma and TNF-alpha production by splenocytes. EAE acute phase and remission animals showed reduced terbutaline-induced inhibition of IFN-gamma production. CONCLUSIONS Disturbed sympathetic-immune communication in EAE is characterized by alterations in adrenergic sensitivity via both alpha- and beta-adrenergic pathways.
Collapse
Affiliation(s)
- Katharina Haerter
- Department of Medical Psychology, University of Essen Medical School, Hufelandstr. 55, 45122 Essen, Germany
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Brown SW, Meyers RT, Brennan KM, Rumble JM, Narasimhachari N, Perozzi EF, Ryan JJ, Stewart JK, Fischer-Stenger K. Catecholamines in a macrophage cell line. J Neuroimmunol 2003; 135:47-55. [PMID: 12576223 DOI: 10.1016/s0165-5728(02)00435-6] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This study provides the first evidence for catecholamine synthesis and release in the RAW264.7 cell line, an important macrophage model. Although catecholamines were low in unstimulated cells, activation with lipopolysaccharide (LPS) induced tyrosine hydroxylase (TH) mRNA and increased extracellular norepinephrine and intracellular dopamine within 48 h. The catecholamine synthesis inhibitor alpha-methyl-para-tyrosine (alpha-mpt) decreased extracellular norepinephrine levels, suggesting release and rapid turnover of newly synthesized norepinephrine. High concentrations of dopamine or norepinephrine (>/=100 microM) decreased proliferation and increased apoptosis of macrophages. These anti-proliferative effects were prevented by simultaneous treatment with the anti-oxidant ascorbic acid. Pre-incubation with a glutathione synthesis inhibitor (L-buthionine-[S,R]-sulfoximine [L-BSO]) increased sensitivity to catecholamine-stimulated apoptosis, suggesting that glutathione protects macrophages from both endogenous and exogenous catecholamines.
Collapse
Affiliation(s)
- Scott W Brown
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Renauld AE, Spengler RN. Tumor necrosis factor expressed by primary hippocampal neurons and SH-SY5Y cells is regulated by alpha(2)-adrenergic receptor activation. J Neurosci Res 2002; 67:264-74. [PMID: 11782970 DOI: 10.1002/jnr.10101] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Neuron expression of the cytokine tumor necrosis factor-alpha (TNF), and the regulation of the levels of TNF by alpha(2)-adrenergic receptor activation were investigated. Adult rat hippocampal neurons and phorbol ester (PMA)-differentiated SH-SY5Y cells were examined. Intracellular levels of TNF mRNA accumulation, as well as TNF protein and that released into the supernatant were quantified by in situ hybridization, immunocytochemistry and bioanalysis, respectively. Both neuron cultures demonstrated constitutive production of TNF. Activation of the alpha(2)-adrenergic receptor increased intracellular levels of TNF mRNA and protein in SH-SY5Y cells after addition of graded concentrations of the selective agonist, Brimonidine (UK-14304) to parallel cultures. Intracellular levels of mRNA were increased in a concentration-dependent fashion within 15 min of UK-14304 addition and were sustained during 24 hr of receptor activation. In addition, the levels of TNF in the supernatant were increased in both types of neuron cultures within 15 min of alpha(2)-adrenergic receptor activation. Furthermore, levels of TNF significantly increased in the supernatants of both neuron cultures after potassium-induced depolarization. A reduction in this depolarization-induced release occurred in hippocampal neuron cultures after exposure to the sympathomimetic tyramine with media replacement to deplete endogenous catecholamines. This finding reveals a role for endogenous catecholamines in the regulation of TNF production. Potassium-induced depolarization resulted in the release of TNF in hippocampal neuron cultures within 15 min but not until 24 hr in SH-SY5Y cultures demonstrating a temporally mediated event dependent upon cell type. Neuron expression of TNF, regulated by alpha(2)-adrenergic receptor activation demonstrates not only how a neuron controls its own production of this pleiotropic cytokine, but also displays a normal role for neurons in directing the many functions of TNF.
Collapse
Affiliation(s)
- A E Renauld
- Department of Pathology, School of Medicine and Biomedical Sciences, Buffalo, New York, USA
| | | |
Collapse
|
14
|
Goebel MU, Mills PJ, Irwin MR, Ziegler MG. Interleukin-6 and tumor necrosis factor-alpha production after acute psychological stress, exercise, and infused isoproterenol: differential effects and pathways. Psychosom Med 2000; 62:591-8. [PMID: 10949106 DOI: 10.1097/00006842-200007000-00019] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE The aim of the study was to assess the effects of three different methods of acute activation of the sympathetic nervous system on lipopolysaccharide-induced in vitro production of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha). METHODS Thirty-two healthy volunteers performed speech and exercise tasks and underwent a 30-minute infusion of isoproterenol. RESULTS As expected, acute activation of the sympathetic nervous system led to leukocytosis, including increases in lymphocyte, monocyte, and granulocyte populations (p values <.05). Lipopolysaccharide-induced IL-6 production was increased after both the speaking and exercise tasks (p values <.001), whereas TNF-alpha production was elevated only after exercise (p<.05). In contrast, infusion of isoproterenol inhibited TNF-alpha production (p<.001) and caused no change in IL-6 production. CONCLUSIONS In response to the challenges, IL-6 and TNF-alpha production showed different profiles. Purely beta-agonist stimulation led to downregulation of TNF-alpha production, providing evidence of the antiinflammatory effect of in vivo beta-receptor activation. The enhanced production of both cytokines after exercise, and of IL-6 after the speech task, can be best explained by a simultaneous upregulation of proinflammatory and inflammation-responding mediators. These effects may have an important role in controlling the immune response to acute psychological and physical stress.
Collapse
Affiliation(s)
- M U Goebel
- Department of Psychiatry, University of California, San Diego, La Jolla, USA.
| | | | | | | |
Collapse
|