scholarly journals Brain Perivascular Macrophages Do Not Mediate Interleukin-1-Induced Sickness Behavior in Rats

2021 ◽  
Vol 14 (10) ◽  
pp. 1030
Author(s):  
Léa Chaskiel ◽  
Robert Dantzer ◽  
Jan Konsman

Sickness behavior, characterized by on overall reduction in behavioral activity, is commonly observed after bacterial infection. Sickness behavior can also be induced by the peripheral administration of Gram-negative bacterial lipopolysaccharide (LPS) or interleukin-1beta (IL-1β), a pro-inflammatory cytokine released by LPS-activated macrophages. In addition to the microglia, the brain contains perivascular macrophages, which express the IL-1 type 1 receptor (IL-1R1). In the present study, we assessed the role of brain perivascular macrophages in mediating IL-1β-induced sickness behavior in rats. To do so, we used intracerebroventricular (icv) administration of an IL-1β-saporin conjugate, known to eliminate IL-R1-expressing brain cells, prior to systemic or central IL-1β injection. Icv IL-1β-saporin administration resulted in a reduction in brain perivascular macrophages, without altering subsequent icv or ip IL-1β-induced reductions in food intake, locomotor activity, and social interactions. In conclusion, the present work shows that icv IL-1β-saporin administration is an efficient way to target brain perivascular macrophages, and to determine whether these cells are involved in IL-1β-induced sickness behavior.

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Takuto Nakamura ◽  
Masanobu Yamazato ◽  
Akio Ishida ◽  
Yusuke Ohya

Objective: Aminopeptidase A (APA) have important role in conversion of Ang II to Ang III. Intravenous APA administration lowers blood pressure in hypertensive rats. In contrast, APA inhibition in the brain lowers blood pressure in hypertensive rats. Therefore APA might have different role on cardiovascular regulation. However, a role of APA and Ang III on cardiovascular regulation especially in the brain has not been fully understood. Our purpose of present study was to investigate a role of APA and Ang III in the brain on cardiovascular regulation in conscious state. Method: 12-13 weeks old Wistar Kyoto rat (WKY) and 12-16 weeks old spontaneously hypertensive rat (SHR) were used. i) APA distribution in the brain was evaluated by immunohistochemistry. Protein expression of APA was evaluated by Western blotting. Enzymatic activity of APA was evaluated using L-glutamic acid γ-(4-nitroanilide) as a substrate. ii) WKY received icv administration of Ang II 25ng/2μL and Ang III 25ng/2μL. We recorded change in mean arterial pressure (MAP) in conscious and unrestraied state and measured induced drinking time. iii) SHR received icv administeration of recombinant APA 400ng/4μL. We recorded change in MAP in conscious and unrestraied state and measured induced drinking time. Result: i) APA was diffusely immunostained in the cells of brain stem including cardiovascular regulatory area such as rostral ventrolateral medulla. Protein expression and APA activity in the brain were similar between WKY (n=3) and SHR (n=3).ii) Icv administration of Ang II increased MAP by 33.8±3.8 mmHg and induced drinking behavior for 405±90 seconds (n=4). Icv administration of Ang III also increased MAP by 24.7±2.4 mmHg and induced drinking behavior for 258±62 seconds (n=3). These vasopressor activity and induced drinking behavior was completely blocked by pretretment of angiotensin receptor type 1 blocker.iii) Icv administration of APA increased MAP by 10.0±1.7 mmHg (n=3). Conclusion: These results suggested that Ang III in the brain increase blood pressure by Angiotensin type 1 receptor dependent mechanism and APA in the brain may involved in blood pressure regulation as a vasopressor enzyme.


1986 ◽  
Vol 250 (5) ◽  
pp. R803-R806 ◽  
Author(s):  
S. T. Shih ◽  
O. Khorram ◽  
J. M. Lipton ◽  
S. M. McCann

alpha-Melanocyte-stimulating hormone (alpha-MSH) has a marked antipyretic action when given centrally or peripherally, and the concentration of this peptide within the septal region of the brain increases during fever. To assess the significance of endogenous central alpha-MSH in fever, antiserum was given to rabbits via a cannula implanted in the third cerebral ventricle. Each day for 3 days, the animals received 50 microliters of normal rabbit serum (NRS) or an equal volume of antiserum raised against alpha-MSH. Interleukin 1 (IL 1) was then injected intravenously to determine the effect of central immunoneutralization of alpha-MSH on the febrile response. Immunoneutralization markedly prolonged fever. The average rise in temperature and the area under the fever curve after IL 1 injection were also significantly increased. Antiserum treatment did not alter normal body temperature, and NRS had no effect on IL 1-induced fever. These results indicate that endogenous central alpha-MSH contributes to physiological limitation of fever and that the role of this peptide in temperature regulation is relevant to the febrile state but not to normothermia.


2016 ◽  
Vol 91 (4) ◽  
Author(s):  
Luiza A. Castro-Jorge ◽  
Carla D. Pretto ◽  
Asa B. Smith ◽  
Oded Foreman ◽  
Kelly E. Carnahan ◽  
...  

ABSTRACT Interleukin-1β (IL-1β), an inflammatory cytokine and IL-1 receptor ligand, has diverse activities in the brain. We examined whether IL-1 signaling contributes to the encephalitis observed in mouse adenovirus type 1 (MAV-1) infection, using mice lacking the IL-1 receptor (Il1r1 −/− mice). Il1r1 −/− mice demonstrated reduced survival, greater disruption of the blood-brain barrier (BBB), higher brain viral loads, and higher brain inflammatory cytokine and chemokine levels than control C57BL/6J mice. We also examined infections of mice defective in IL-1β production (Pycard −/− mice) and mice defective in trafficking of Toll-like receptors to the endosome (Unc93b1 −/− mice). Pycard −/− and Unc93b1 −/− mice showed lower survival (similar to Il1r1 −/− mice) than control mice but, unlike Il1r1 −/− mice, did not have increased brain viral loads or BBB disruption. Based on the brain cytokine levels, MAV-1-infected Unc93b1 −/− mice had a very different inflammatory profile from infected Il1r1 −/− and Pycard −/− mice. Histological examination demonstrated pathological findings consistent with encephalitis in control and knockout mice; however, intranuclear viral inclusions were seen only in Il1r1 −/− mice. A time course of infection of control and Il1r1 −/− mice evaluating the kinetics of viral replication and cytokine production revealed differences between the mouse strains primarily at 7 to 8 days after infection, when mice began succumbing to MAV-1 infection. In the absence of IL-1 signaling, we noted an increase in the transcription of type I interferon (IFN)-stimulated genes. Together, these results indicate that IL-1 signaling is important during MAV-1 infection and suggest that, in its absence, increased IFN-β signaling may result in increased neuroinflammation. IMPORTANCE The investigation of encephalitis pathogenesis produced by different viruses is needed to characterize virus and host-specific factors that contribute to disease. MAV-1 produces viral encephalitis in its natural host, providing a good model for studying factors involved in encephalitis development. We investigated the role of IL-1 signaling during MAV-1-induced encephalitis. Unexpectedly, the lack of IL-1 signaling increased the mortality and inflammation in mice infected with MAV-1. Also, there was an increase in the transcription of type I IFN-stimulated genes that correlated with the observed increased mortality and inflammation. The findings highlight the complex nature of encephalitis and suggests that IL-1 has a protective effect for the development of MAV-1-induced encephalitis.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Attila Bebes ◽  
Ferenc Kovács-Sólyom ◽  
Judit Prihoda ◽  
Róbert Kui ◽  
Lajos Kemény ◽  
...  

This study was carried out to examine the possible role of interleukin-1 (IL-1) in the functional insufficiency of regulatory T cells in psoriasis, by comparing the expression of IL-1 receptors on healthy control and psoriatic T cells. Patients with moderate-to-severe chronic plaque psoriasis and healthy volunteers, matched in age and sex, were selected for all experiments. CD4+CD25−effector and CD4+CD25+CD127lowregulatory T cells were separated and used for the experiments. Expression of the mRNA of IL-1 receptors (IL-1R1, IL-1R2, and sIL-1R2) was determined by quantitative real-time RT-PCR. Cell surface IL-1 receptor expression was assessed by flow cytometry. Relative expression of the signal transmitting IL-1 receptor type 1 (IL-1R1) mRNA is higher in resting psoriatic effector and regulatory T cells, and activation induces higher IL-1R1 protein expression in psoriatic T cells than in healthy cells. Psoriatic regulatory and effector T cells express increased mRNA levels of the decoy IL-1 receptors (IL-1R2 and sIL-1R2) upon activation compared to healthy counterparts. Psoriatic T cells release slightly more sIL-1R2 into their surrounding than healthy T cells. In conclusion, changes in the expression of IL-1 receptors in psoriatic regulatory and effector T cells could contribute to the pathogenesis of psoriasis.


Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 152
Author(s):  
Barbara Balestrieri ◽  
David Di Costanzo ◽  
Daniel F. Dwyer

Macrophages have diverse functions in the pathogenesis, resolution, and repair of inflammatory processes. Elegant studies have elucidated the metabolomic and transcriptomic profiles of activated macrophages. However, the versatility of macrophage responses in inflammation is likely due, at least in part, to their ability to rearrange their repertoire of bioactive lipids, including fatty acids and oxylipins. This review will describe the fatty acids and oxylipins generated by macrophages and their role in type 1 and type 2 immune responses. We will highlight lipidomic studies that have shaped the current understanding of the role of lipids in macrophage polarization.


2005 ◽  
Vol 25 (1) ◽  
pp. 17-29 ◽  
Author(s):  
Anirban Basu ◽  
Jelena Lazovic ◽  
J Kyle Krady ◽  
David T Mauger ◽  
Raymond P Rothstein ◽  
...  

Excessive inflammation has been implicated in the progressive neurodegeneration that occurs in multiple neurological diseases, including cerebral ischemia, and elevated levels of the proinflammatory cytokine interleukin-1 (IL-1) have been shown to exacerbate brain damage, whereas diminishing IL-1 levels limits the extent of injury. However, to date there is no consensus regarding which receptor(s) mediates the detrimental effects of IL-1. Because we have previously demonstrated that signaling through the IL-1 type 1 receptor (IL-1R1) is necessary for microglial activation and because results from other studies have implicated microglia as effectors of neurodegeneration, we hypothesized that inactivating the IL-1R1 would decrease the extent of damage caused by a hypoxic-ischemic (H/I) insult. It is shown that a mild insult initiates progressive neurodegeneration that leads to cystic infarcts, which can be prevented by inactivating the IL-1R1. The IL-1R1 null mice also show preserved sensorimotor function at 1 month's recovery. The mild insult induces multiple proinflammatory cytokines and activates microglia, and these responses are dramatically curtailed in mice lacking the IL-1R1. Importantly, the neuroinflammation precedes the progressive enlargement of the infarct, suggesting that the inflammation is causal rather than a consequence of the brain damage. These findings show that abrogating the inflammation consequent to a mild H/I insult will prevent brain damage and preserve neurological function. Additionally, these data incriminate the IL-1R1 as a master proinflammatory cytokine receptor.


1992 ◽  
Vol 15 ◽  
pp. 663A-664A
Author(s):  
ERROL B. DE SOUZA ◽  
TOSHIHIRO TAKAO
Keyword(s):  

Cytokine ◽  
1995 ◽  
Vol 7 (7) ◽  
pp. 710-712 ◽  
Author(s):  
Hajime Watanobe ◽  
Shinsuki Sasaki ◽  
Kazuo Takebe
Keyword(s):  

2008 ◽  
Vol 21 (3) ◽  
pp. 259-276 ◽  
Author(s):  
Carlo Salvato ◽  
Leif Melin

This article explores the processes through which family-controlled businesses (FCBs) access and recombine resources to match the evolving needs of their business activities. We do so by applying the conceptual lens offered by social capital to the comparative study of four FCBs active in traditional competitive arenas. Our data reveal that these firms' ability to create financial value over generations does not result from possession of some unique resource, nor from higher-level combinative capabilities; rather, these FCBs have systematically created value through their ability to renew and to reshape their social interactions within and outside the controlling family.


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