Smith, Dirk E; Hanna, Roberta; Della Friend; Moore, Heather; Chen, Hongbo; Farese, Ann M; MacVittie, Thomas J; Virca, G Duke; Sims, John E
Regulation of the activity of the proinflammatory cytokine IL-1 is complex, involving transcriptional and translational control, precursor processing, a receptor antagonist (IL-1ra), and a decoy receptor. Here we report that the soluble form of the IL-1 receptor accessory protein (AcP) increases the affinity of binding of human IL-1alpha and IL-1beta to the soluble human type II IL-1 receptor by approximately 100-fold, while leaving unaltered the low binding affinity of IL-1ra. Soluble AcP is present in normal human serum at an average concentration greater than 300 ng/ml. These findings suggest that the soluble form of IL-1R AcP contributes to the antagonism of IL-1 action by the type II decoy receptor, adding another layer of complexity to the regulation of IL-1 action.
Maedler, Kathrin; Sergeev, Pavel; Ehses, Jan A.; Mathe, Zoltan; Bosco, Domenico; Berney, Thierry; Dayer, Jean-Michel; Reinecke, Manfred; Halban, Philippe A.; Donath, Marc Y.
High concentrations of glucose induce β cell production of IL-1β, leading to impaired β cell function and apoptosis in human pancreatic islets. IL-1 receptor antagonist (IL-1Ra) is a naturally occurring antagonist of IL-1β and protects cultured human islets from glucotoxicity. Therefore, the balance of IL-1β and IL-1Ra may play a crucial role in the pathogenesis of diabetes. In the present study, we observed expression of IL-1Ra in human pancreatic β cells of nondiabetic individuals, which was decreased in tissue sections of type 2 diabetic patients. In vitro, chronic exposure of human islets to leptin, a hormone secreted by adipocytes, decreased β cell production of IL-1Ra and induced IL-1β release from the islet preparation, leading to impaired β cell function, caspase-3 activation, and apoptosis. Exogenous addition of IL-1Ra protected cultured human islets from the deleterious effects of leptin. Antagonizing IL-1Ra by introduction of small interfering RNA to IL-1Ra into human islets led to caspase-3 activation, DNA fragmentation, and impaired β cell function. Moreover, siIL-1Ra enhanced glucose-induced β cell apoptosis. These findings demonstrate expression of IL-1Ra in the human β cell, providing localized protection against leptin- and glucose-induced islet IL-1β. PMID:15141093
Casadio, R; Frigimelica, E; Bossù, P; Neumann, D; Martin, M U; Tagliabue, A; Boraschi, D
A preliminary model has been calculated for the activating interaction of the interleukin 1 receptor (IL-1R) accessory protein IL-1RAcP with the ligand/receptor complex IL-1beta/IL-1R(I). First, IL-1RAcP was modeled on the crystal structure of IL-1R(I) bound to IL-1beta. Then, the IL-1RAcP model was docked using specific programs to the crystal structure of the IL-1beta/IL-1R(I) complex. Two types of models were predicted, with comparable probability. Experimental data obtained with the use of IL-1beta peptides and antibodies, and with mutated IL-1beta proteins, support the BACK model, in which IL-1RAcP establishes contacts with the back of IL-1R(I) wrapped around IL-1beta.
Wakabayashi, Chisato; Numakawa, Tadahiro; Odaka, Haruki; Ooshima, Yoshiko; Kiyama, Yuji; Manabe, Toshiya; Kunugi, Hiroshi; Iwakura, Yoichiro
Interleukin 1 (IL-1) plays a critical role in stress responses, and its mRNA is induced in the brain by restraint stress. Previously, we reported that IL-1 receptor antagonist (IL-1Ra) knockout (KO) mice, which lacked IL-1Ra molecules that antagonize the IL-1 receptor, showed anti-depression-like behavior via adrenergic modulation at the age of 8 weeks. Here, we report that IL-1Ra KO mice display an anxiety-like phenotype that is induced spontaneously by aging in the elevated plus-maze (EPM) test. This anxiety-like phenotype was improved by the administration of diazepam. The expression of the anxiety-related molecule glucocorticoid receptor (GR) was significantly reduced in 20-week-old but not in 11-week-old IL-1Ra KO mice compared to wild-type (WT) littermates. The expression of the mineralocorticoid receptor (MR) was not altered between IL-1Ra KO mice and WT littermates at either 11 or 20 weeks old. Analysis of monoamine concentration in the hippocampus revealed that tryptophan, the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), and the dopamine metabolite homovanillic acid (HVA) were significantly increased in 20-week-old IL-1Ra KO mice compared to littermate WT mice. These findings strongly suggest that the anxiety-like behavior observed in older mice was caused by the complicated alteration of monoamine metabolism and/or GR expression in the hippocampus.
Libra, Massimo; Mangano, Katia; Anzaldi, Massimiliano; Quattrocchi, Cinzia; Donia, Marco; di Marco, Roberto; Signorelli, Santo; Scalia, Guido; Zignego, Anna L; de Re, Valli; Mazzarino, Maria C; Nicoletti, Ferdinando
Hepatitis C virus (HCV) causes hepatitis, liver cirrhosis and hepatocellular carcinoma, and may also induce type II mixed cryoglobulinemia syndrome (MC), a disease characterized by clonal B-cell lymphoproliferations that can evolve into non-Hodgkin's lymphoma (NHL). Interleukin-1 (IL-1) is a cytokine that plays an important role in initiating the cascade of events of immunoinflammatory responses through costimulation of T lymphocytes, B-cell proliferation, induction of adhesion molecules and stimulation of the production of other inflammatory cytokines. The role of IL-1 in immunoinflammatory responses is highlighted by the presence of endogenous regulators (IL-1 receptor antagonist, soluble receptors type 1 and II, human IL-1 accessory protein) that, when secreted into the blood stream may serve as endogenous regulators of IL-1 action. The aim of this study was to evaluate whether abnormalities in the blood levels of IL-1beta IL-1 receptor antagonist, soluble IL-1 receptor type II and human IL-1 accessory protein in HCV+ patients are associated with development of MC and/or NHL. Relative to healthy controls, we observed: i) an increase in the circulating levels of IL-1beta in HCV+ patients simultaneously affected by NHL; ii) increased levels of IL-1 accessory protein in patients singly infected by HCV; iii) increase of IL-1 receptor antagonist in HCV+ patients and in those affected also by NHL with or without MC; iv) a homogeneous increase of sIL-1R type II in all the subgroup of patients. These data indicate that an attempt to increased circulating levels of IL-1 inhibitors occurs at different extent in the course of HCV infection as well as in its progression to NHL and/or MC.
Lang, D; Knop, J; Wesche, H; Raffetseder, U; Kurrle, R; Boraschi, D; Martin, M U
IL-1 binds to two types of receptors on the cell membrane, of which only type I (IL-1RI) transduces signals in concert with the coreceptor IL-1 receptor accessory protein (IL-1RAcP) while type II (IL-1RII) allegedly functions solely as ligand sink and decoy receptor without participating in IL-1 signaling. To investigate the regulatory role of IL-1RII on IL-1 responsiveness, a chimeric receptor encompassing the extracellular and transmembrane portions of IL-1RII and the cytoplasmic signal-transducing domain of IL-1RI was transfected into two murine EL-4-derived sublines that do or do not express IL-1RAcP, respectively. The chimeric receptor was able to transduce the IL-1 signal and induce IL-2 production only in the cell line which expressed IL-1RAcP, suggesting effective interaction between the extracellular domains of IL-1RII and IL-1RAcP in the presence of IL-1. The physical association of ligated IL-1RII with IL-1RAcP was proven by crosslinking experiments with radio-iodinated IL-1 and subsequent immunoprecipitations in normal human B cells and in EL-4 D6/76 cells transiently cotransfected with IL-1RII and IL-1RAcP, respectively. Based on these findings, it is proposed that upon IL-1 binding IL-1RII can recruit IL-1RAcP into a nonfunctional trimeric complex and thus modulate IL-1 signaling by subtracting the coreceptor molecule from the signaling IL-1RI. In this novel mechanism of coreceptor competition, the ratio between IL-1RII and IL-1RI becomes the central factor in determining the IL-1 responsiveness of a cell and the availability of IL-1RAcP becomes limiting for effective IL-1 signaling.
Yang, Qiong; Chu, Qing; Zhao, Xueyan; Xu, Tianjun
Interleukin (IL)-1β is a prototypical proinflammatory cytokine that belongs to the IL-1 family. This cytokine possesses two receptor types, namely, IL-1 receptor type I (IL-1RI) and IL-1 receptor type II (IL-1RII). IL-1RI, is an IL-1 receptor that plays a crucial role in immune responses and IL-1RII is a decoy receptor for IL-1β signaling inhibitors in mammals. IL-1β, together with its two types of receptors, has been characterized in mammals and implicated in immunity. However, IL-1β and IL-1 receptors in teleost species have been rarely investigated. In this study three genes, namely, IL-1β, IL-1RI, and IL-1RII, were identified and characterized from miiuy croaker. Structural and comparative analysis revealed that miiuy croaker IL-1β, IL-1RI and IL-1RII, particularly their functional domains, were conservative in most of the species. Simultaneously, synteny phylogenetic analysis indicated that IL-1β and IL-18 were widely distributed in vertebrates and hence might be the ancestors of the IL-1 family. Challenge experiment demonstrated that IL-1β, IL-1RI and IL-1RII expression in miiuy croaker was induced by LPS and poly (I:C). IL-1RI expression was also induced by the overexpressed miiuy croaker IL-1β protein which in cell supernatant, whereas IL-1RII was not induced. Copyright © 2017 Elsevier Ltd. All rights reserved.
Bioque, G; Crusius, J B; Koutroubakis, I; Bouma, G; Kostense, P J; Meuwissen, S G; Peña, A S
Recent reports have shown that allele 2 of the IL-1 receptor antagonist (IL-1Ra) gene is over-represented in ulcerative colitis (UC). Healthy individuals carrying allele 2 of this gene have increased production of IL-1Ra protein. Since the final outcome of the biological effects of IL-1 beta may depend on the relative proportion of these two cytokines, we have studied if a TaqI polymorphism in the IL-1 beta gene, which is relevant to IL-1 beta protein production, may be involved in the genetic susceptibility to UC and Crohn's disease (CD), in association with the established IL-1Ra gene polymorphism. Polymorphisms in the closely linked genes for IL-1 beta and IL-1Ra were typed in 100 unrelated Dutch patients with UC, 79 with CD, and 71 healthy controls. The polymorphic regions in exon 5 of the IL-1 beta gene and in intron 2 of the IL-1Ra gene, were studied by polymerase chain reaction (PCR)-based methods. The IL-1 beta allele frequencies in UC and CD patients did not differ from those in healthy controls. In order to study if the IL-1 beta gene polymorphism might participate synergistically with the IL-1Ra gene polymorphism in susceptibility to UC and CD, individuals were distributed into carriers and non-carriers of allele 2 of the genes encoding IL-1 beta and IL-1Ra, in each of the patient groups and controls. Results indicated a significant association of this pair of genes, estimated by the odds ratio (OR) after performing Fisher's exact test, in the UC group (P = 0.023, OR = 2.81), as well as in the CD group (P = 0.01, OR = 3.79). Thus, non-carriers of IL-1 beta allele 2 were more often present in the subgroup of patients carrying the IL-1Ra allele 2. By contrast, no association of these alleles was detected in the group of healthy controls (P = 1.00, OR = 0.92). These results suggest that the IL-1 beta/IL-1Ra allelic cluster may participate in defining the biological basis of predisposition to chronic inflammatory bowel diseases. PMID:7586694
Kanemoto, K; Kawasaki, J; Miyamoto, T; Obayashi, H; Nishimura, M
Proinflammatory cytokines, including interleukin (IL)-1beta, are known to modulate effects of neurotoxic neurotransmitters discharged during excitation or inflammation in the central nervous system (CNS). They also regulate development of glial scars at sites of CNS injury. To elucidate a genetic predisposition of temporal lobe epilepsy with hippocampal sclerosis (TLE-HS+), we studied polymorphisms in the IL-1beta, IL-1alpha, and IL-1 receptor antagonist (IL-1RA) genes in 50 patients with TLE-HS+ and in 112 controls. Fifty-three patients who had TLE without HS were also examined (TLE-HS-) as disease controls. The distribution of the biallelic polymorphism in the promoter region at position -511 of the IL-1beta gene (IL-1B-511) was significantly different both between TLE-HS+ patients and controls and between TLE-HS+ and TLE-HS- patients. The differences were due to overrepresentation of the homozygotes for IL-1B-511*2, which is suggested to be a high producer of IL-1beta, in TLE-HS+ patients compared with both controls and TLE-HS- patients. In contrast, there was no difference between TLE-HS- patients and controls. Our data suggest that, in the homozygotes for IL-IB-511*2, minor events in development such as febrile convulsions could set up a cascade leading to HS.
Cogulu, Dilsah; Onay, Huseyin; Ozdemir, Yasemin; I Aslan, Gulcin; Ozkinay, Ferda; Kutukculer, Necil; Eronat, Cemal
Streptococcus mutans is important in dental caries. Although the role of cytokines in the pathogenesis of dental caries is not clear, components of S. mutans were found to stimulate production of pro-inflammatory cytokines. We examined the associations of interleukin (IL)-1β, IL-1 receptor antagonist (IL-1ra), and IL-10 with dental caries. Unstimulated whole saliva and blood samples were obtained from 108 children aged 6-12 years with high caries (decayed, missing, or filled teeth [dmft/DMFT] index >4, n = 37), moderate caries (dmft/DMFT = 1-4, n = 37), or caries-free (dmft/DMFT = 0, n = 34). S. mutans level was classified as low (<10(5) colony-forming units [CFU]/mL) or high (≥10(5) CFU/mL). Saliva and serum concentrations of IL-1β, IL-1ra, and IL-10 were determined by ELISA. IL-1β, IL-1ra, and IL-10 gene polymorphisms were genotyped using PCR and restriction fragment length polymorphism analysis. The chi-square, Mann-Whitney U, one-way ANOVA, posthoc, Fisher's exact, and t tests were used in statistical analysis. Dental caries was not correlated with salivary or serum concentrations of the studied cytokines. S. mutans level positively correlated with saliva IL-1β concentration and inversely correlated with saliva IL-1ra concentration. There was no correlation of IL-1β, IL-1ra, or IL-10 gene polymorphisms with dental caries. S. mutans is important in stimulating saliva IL-1β and inhibiting IL-1ra. Future studies of associations between cytokines and dental caries should investigate additional cytokines and enroll a larger number of participants.
Bajayo, Alon; Goshen, Inbal; Feldman, Sharon; Csernus, Valer; Iverfeldt, Kerstin; Shohami, Esther; Yirmiya, Raz; Bab, Itai
The proinflammatory cytokine IL-1, acting via the hypothalamic IL-1 receptor type 1 (IL-1RI), activates pathways known to suppress bone formation such as the hypothalamo pituitary-adrenocortical axis and the sympathetic nervous system. In addition, peripheral IL-1 has been implicated as a mediator of the bone loss induced by sex hormone depletion and TNF. Here, we report an unexpected low bone mass (LBM) phenotype, including impairment of bone growth, in IL-1RI-deficient mice (IL-1rKO mice). Targeted overexpression of human IL-1 receptor antagonist to the central nervous system using the murine glial fibrillary acidic protein promoter (IL-1raTG mice) resulted in a similar phenotype, implying that central IL-1RI silencing is the causative process in the LBM induction. Analysis of bone remodeling indicates that the process leading to the LBM in both IL-1rKO and IL-1raTG is characterized mainly by doubling the osteoclast number. Either genetic modification does not decrease testosterone or increase corticosterone serum levels, suggesting that systems other than the gonads and hypothalamo pituitary-adrenocortical axis mediate the central IL-1RI effect on bone. We further demonstrate that WT mice express mouse IL-1ra in bone but not in the hypothalamus. Because low levels of IL-1 are present in both tissues, it is suggested that skeletal IL-1 activity is normally suppressed, whereas central IL-1 produces a constant physiologic stimulation of IL-1RI signaling. Although the pathway connecting the central IL-1RI signaling to bone remodeling remains unknown, the outburst of osteoclastogenesis in its absence suggests that normally it controls bone growth and mass by tonically restraining bone resorption. PMID:16126903
Cullinan, E B; Kwee, L; Nunes, P; Shuster, D J; Ju, G; McIntyre, K W; Chizzonite, R A; Labow, M A
The recently described IL-1R accessory protein (IL-1R AcP) interacts with IL-1beta and the IL-1 type-IR (IL-1RI), but an essential requirement for IL-1R AcP in IL-1 signaling in vitro has not been established and its role in vivo has not been examined. In this study, IL-1R AcP-deficient mice and fibroblasts were produced and characterized. All IL-1 agonists bound to IL-1R AcP-deficient cells through the type I IL-1R, but failed to activate gene expression through either the nuclear factor-kappaB or AP-1-dependent signaling pathways. Absence of IL-1R AcP differentially affected the affinity for IL-1 ligands. IL-1R AcP-deficient fibroblasts bound murine IL-1alpha and human IL-1R antagonist protein (IL-1Ra) with only moderately reduced affinity when compared with wild-type cells, whereas murine IL-1beta affinity was reduced by 70-fold. IL-1 also failed to produce a biologic response in vivo in IL-1R AcP-deficient mice. These data demonstrate that a type I IL-1R/IL-1R AcP complex is required for signaling by all IL-1 agonists and for high affinity binding by IL-1beta. Finally, IL-1R AcP is an essential signal transducing component of the functional IL-1R and should represent a novel target for blocking IL-1 function in human disease.
Boraschi, D; Bossù, P; Ruggiero, P; Tagliabue, A; Bertini, R; Macchia, G; Gasbarro, C; Pellegrini, L; Melillo, G; Ulisse, E; Visconti, U; Bizzarri, C; Del Grosso, E; Mackay, A R; Frascotti, G; Frigerio, F; Grifantini, R; Grandi, G
Upon structure comparison between IL-1 beta and its antagonist IL-1ra, single or multiple residues along the IL-1 beta sequence were replaced with the corresponding amino acids present in the IL-1ra protein, in the attempt to identify sites important for receptor binding and for biologic activity on the two molecules. Ten of fifteen mutant proteins had activity comparable to that of wild-type IL-1 beta in three different biologic assays and in receptor binding, indicating that the introduced changes did not influence the functional structure of the protein. Conversely, three mutants (SMIL-9: 127/263 R/T-->W/Y; SMIL-10: 125/127/263/265 T/R/T/Q-->R/W/Y/E; SMIL-15:222/227 I/E-->S/S) showed an increased binding capacity for IL-1RI, not paralleled by increased agonist activity, indicating that the introduced IL-1ra residues could be involved in the nonagonist IL-1RI binding site. On the other hand, two mutants showed diminished binding capacity with concomitant decrease in biologic activity. Both mutants (SMIL-1, five substitutions in the loop 202-214; and SMIL-3, total replacement of the loop 164-173 with the IL-1ra stretch 52-55) included substitutions of residues allegedly important for agonist binding to IL-1RI. Mutant SMIL-3 showed the most profound reduction in binding capacity for IL-1RI (CDw121a) and a more than 1,000-fold reduced biologic activity both in vitro and in vivo, but it retained full capacity of binding to IL-1RII (CDw121b) and acted as a selective antagonist of IL-1RII. From these results the following conclusions can be drawn. IL-1 beta binds to IL-1RI and to IL-1RII through different sites, and the loop 164-173 appears as one of the areas involved in the selective interaction with IL-1RI. Agonist (IL-1 beta) and nonagonist (IL-1ra) binding to IL-1RI occur through distinct sites, with loops 164-173 and 202-214 of IL-1 beta identified as two of the sites selectively involved in agonist binding to the activating receptor.
Koch, H; Reinecke, J A; Meijer, H; Wehling, P
In the study presented, cells of a herniated lumbar disc were cultivated in vitro and analysed for interleukin 1beta (IL-1beta) and interleukin 1 receptor antagonist (IL-1Ra) production. The objective of this study was the detection of IL-1beta and IL-1Ra secreted by herniated lumbar discal cells after discectomy. The involvement of cytokines in the degeneration of intervertebral discs and in the pathophysiology of radiculopathy is established. Antagonizing proteins, e.g. IL-1Ra are thought to have considerable therapeutic potential. In the present study, a 51-year-old male with massive sequestrated lumbar disc herniation at L5/S1 was treated by microsurgical discectomy. Discal cells were isolated, cultures and culture supernatants immunochemically analysed for IL-1beta and IL-1Ra secretion. Spontaneous secretion of IL-1Ra was found. IL-1beta was not detected. Our findings might contradict recent studies on the role of IL-1beta and IL-1Ra. A possible therapeutic role of exogenous IL-1Ra in disc degeneration needs further research.
Medel-Matus, Jesús-Servando; Álvarez-Croda, Dulce-Mariely; Martínez-Quiroz, Joel; Beltrán-Parrazal, Luis; Morgado-Valle, Consuelo; López-Meraz, María-Leonor
Interleukin-1β (IL-1β) is associated with seizure-induced neuronal cell death in the adult brain. The contribution of IL-1β to neuronal injury induced by status epilepticus (SE) in the immature brain remains unclear. In the present study, we investigated the effects of IL-1β administration on hippocampal neuronal cell death associated with SE in the immature brain, and the role of the type I receptor of IL-1β (IL-1RI). SE was induced with lithium-pilocarpine in 14-days-old (P14) rat pups. Six hours after SE onset, pups were i.c.v. injected in the right ventricle with IL-1β (0, 0.3, 3, 30, or 300 ng), 30 ng of IL-1RI antagonist (IL-1Ra) alone, or 30 ng of IL-1Ra plus 3ng of IL-1β. As control groups, pups without seizures were injected with 3 ng of IL-1β or vehicle. Twenty-four hours after SE onset, neuronal cell death in the CA1 field of dorsal hippocampus was assessed by hematoxylin-eosin, Fluoro-Jade B and in vivo propidium iodide (PI) staining; expression of active caspase-3 (aCas-3) was also determined, using immunohistochemistry. The concentration-response curve of IL-1β showed a bell-shape. Only pups injected with 3 ng of IL-1β after SE showed a significant increase in the number of cells with eosinophilic cytoplasm and pyknotic nuclei, as well as F-JB positive cells with respect to the vehicle group. This effect was prevented when IL-1β was injected with IL-1Ra. Injection of 3 ng of IL-1β increased the number of PI-positive cells in CA1 area after SE. Injection of 3 ng of IL-1β did not produce hippocampal cell death in rats without seizures. Active caspase-3 expression was not observed after treatments in hippocampus. The activation of the IL-1β/IL-1RI system increases necrotic neuronal cell death caused by SE in rat pups.
Chackerian, Alissa A; Oldham, Elizabeth R; Murphy, Erin E; Schmitz, Jochen; Pflanz, Stefan; Kastelein, Robert A
IL-33 (IL-1F11) is a recently described member of the IL-1 family of cytokines that stimulates the generation of cells, cytokines, and Igs characteristic of a type 2 immune response. IL-33 mediates signal transduction through ST2, a receptor expressed on Th2 and mast cells. In this study, we demonstrate that IL-33 and ST2 form a complex with IL-1R accessory protein (IL-1RAcP), a signaling receptor subunit that is also a member of the IL-1R complex. Additionally, IL-1RAcP is required for IL-33-induced in vivo effects, and IL-33-mediated signal transduction can be inhibited by dominant-negative IL-1RAcP. The implications of this shared usage of IL-1RAcP by IL-1(alpha and beta) and IL-33 are discussed.
Dale, M; Nicklin, M J
The family of interleukin-1 receptor-like genes currently has six known members. We have constructed a contig of 10 overlapping human PAC clones that covers 530 kb and includes five of the six family members. The termini of the contig were mapped to the interval between D2S373 and D2S176 (chromosome 2q12) by radiation hybrid mapping. The contig contains the genes (cen --> tel), in the order given, for the type II interleukin-1 (IL-1) receptor (IL1R2), the type I IL-1 receptor (IL1R1), the IL-1 receptor-related protein 2 (IL1RL2), T1/ST2/fit-1 (IL1RL1), and the IL-1 receptor-related protein 1, which has recently been shown to be a component of the IL-18 receptor (IL18R1). We show that all the genes are transcribed in the same direction, with IL1R2 being transcribed toward the cluster. The only known family member that is absent from the human contig is the IL-1 receptor accessory protein gene (IL1RAP), which maps to 3q28. Copyright 1999 Academic Press.
Matsushima, K.; Akahoshi, T.; Yamada, M.; Furutani, Y.; Oppenheim, J.J.
The properties of specific human interleukin 1 (IL 1) receptors on human Epstein Barr virus-transformed B lymphocytes (EBV-B) were studied. Purified human IL 1-..beta.. from a myelomonocytic cell line (THP-1) was labeled with /sup 125/I. Among four EBV-B cell lines tested, a pre-B cell type (VDS-O) specifically bound the highest amount of /sup 125/I-IL 1-..beta... The binding of /sup 125/I-IL 1-..beta.. to VDS-O cells was inhibited by F(ab)'/sub 2/ fragments of anti-human IL 1 and recombinant human IL 1-..cap alpha.., as well as by unlabeled human IL 1-..beta.. but not by recombinant lymphotoxin, recombinant tumor necrosis factor, or phorbol myristic acid, suggesting that IL 1-..cap alpha.. and IL 1-..beta.. bind specifically to the same receptor. The m.w. of IL 1 receptor on human EBV-B cells was estimated to be 60,000 by both the chemical cross-linking method and high pressure liquid chromatography (HPLC). The isoelectric point of solubilized human IL 1 receptor was 7.3 on HPLC chromatofocusing. The evidence of existence of IL 1 receptor on human EBV-B cells additionally supports the hypothesis that IL 1 may be an autocrine signal for these cells.
Yoon, D Y; Dinarello, C A
The IL-1R accessory protein (IL-1RAcP) plays a role in IL-1R signaling by forming a complex with IL-1RI bound to the IL-1 ligand. We identified four hydrophilic peptide regions of the extracellular IL-1RAcP that may be available for complex formation (peptide 1, 71-83 domain I; peptide 2, 204-211 domain II; peptide 3, 282-292 domain III; and peptide 4, 304-314 domain III). These peptides were synthesized, coupled to keyhole limpet hemocyanin, and used to produce rabbit antisera. Each affinity-purified antiserum showed specificity for the respective peptide without cross-reactivity. Anti-peptide 2, 3, and 4 recognized surface expression of IL-1RAcP on the Th2 D10S cells by FACS and inhibited IL-1-driven proliferation. Anti-peptide 4 recognized intact IL-1RAcP and soluble IL-1RAcP. Anti-IL-1RAcP-peptide 4, which targets the terminal segment of domain III, inhibited 80% of IL-1 beta-driven proliferation of D10S cells. However, these IL-1RAcP Abs had no effect on the activity of human or mouse IL-1 alpha. Whereas IL-1 beta down-regulated IL-1RI surface expression (p < 0.05), there was no change in the surface expression of IL-1RAcP. Moreover, murine IL-10 increased surface expression of IL-1RI, but did not affect expression of IL-1RAcP or the proliferation of D10S cells. Steady state levels of mRNA for IL-1RAcP and IL-1RI in D10S cells showed a similar pattern to that of surface expression of the respective receptors. We conclude that 1) blocking IL-1RAcP inhibits IL-1 signaling in D10S cells, 2) domains-II and III may be involved in complex formation with IL-1RI, 3) IL-1RAcP is not regulated as is IL-1RI in the same cells, and 4) IL-1 responsiveness is dependent on the expression of IL-1RI, not IL-1RAcP.
Cominelli, F; Nast, C C; Clark, B D; Schindler, R; Lierena, R; Eysselein, V E; Thompson, R C; Dinarello, C A
Interleukin 1 (IL-1) may be a key mediator of inflammation and tissue damage in inflammatory bowel disease (IBD). In rabbits with immune complex-induced colitis, IL-1 alpha and beta mRNA levels were detectable at 4 h, peaked at 12 but were absent at 96 h after the induction of colitis. Colonic IL-1 tissue levels were measured by specific radioimmunoassays. IL-1 alpha was significantly elevated at 4 h (9.4 +/- 1.5 ng/g colon), progressively increased at 48 h (31 +/- 5.8 ng/g) and then decreased by 96 h (11.5 +/- 3.4 ng/g). IL-1 beta levels were 2.0 +/- 0.5 ng/g colon at 4 h, 5.0 +/- 1.6 ng/g at 48 h and undetectable by 96 h. By comparison, colonic levels of PGE2 and LTB4 were unchanged during the first 12 h and did not become elevated until 24 h. IL-1 alpha levels were highly correlated with inflammation (r = 0.885, P less than 0.0001), edema (r = 0.789, P less than 0.0001) and necrosis (r = 0.752, P less than 0.0005). Treatment with a specific IL-1 receptor antagonist (IL-1 ra) before and during the first 33 h after the administration of immune complexes markedly reduced inflammatory cell infiltration index (from 3.2 +/- 0.4 to 1.4 +/- 0.3, P less than 0.02), edema (from 2.2 +/- 0.4 to 0.6 +/- 0.3, P less than 0.01) and necrosis (from 43 +/- 10% to 6.6 +/- 3.2%, P less than 0.03) compared to vehicle-matched colitis animals. These studies demonstrate that (a) IL-1 gene expression and synthesis occur early in the course of immune complex-induced colitis; (b) are significantly elevated for 12 h before the appearance of PGE2 and LTB4; (c) tissue levels of IL-1 correlate with the degree of tissue inflammation and; (d) specific blockade of IL-1 receptors reduces the inflammatory responses associated with experimental colitis. Images PMID:2168444
Garlanda, Cecilia; Riva, Federica; Bonavita, Eduardo; Gentile, Stefania; Mantovani, Alberto
Members of the IL-1 family play a key role in innate and adaptive immunity and in the pathogenesis of diverse diseases. Members of IL-1R like receptor (ILR) family include signaling molecules and negative regulators. The latter include decoy receptors (IL-1RII; IL-18BP) and “receptors” with regulatory function (TIR8/SIGIRR; IL-1RAcPb; DIGIRR). Structural considerations suggest that also TIGIRR-1 and IL-1RAPL may have regulatory function. The presence of multiple pathways of negative regulation of members of the IL-1/IL-1R family emphasizes the need for a tight control of members of this fundamental system. PMID:23847621
Polentarutti, Nadia; Rol, Giselle Penton; Muzio, Marta; Bosisio, Daniela; Camnasio, Marco; Riva, Federica; Zoja, Carla; Benigni, Ariela; Tomasoni, Susanna; Vecchi, Annunciata; Garlanda, Cecilia; Mantovani, Alberto
TIR8, also known as single Ig IL-1R-related molecule (SIGIRR), is a member of the IL-1 receptor family. The present study was designed to investigate the expression and function of TIR8. TIR8 was mainly expressed in mouse and human epithelial tissues such as kidney, lung and gut. Resting and activated T and B lymphocytes and monocytes-macrophages expressed little or no TIR8, with the exception of the mouse GG2EE macrophage line. In the kidney, the organ with highest mRNA levels, TIR8 expression was confined to epithelial cells and, in situ, to tubular epithelium. A variety of signals failed to regulate TIR8 expression, but LPS reduced TIR8 mRNA transcripts. An NF-kB driven reporter system was used to investigate the function of TIR8. TIR8 did not activate NF-kB expression alone or in concert with IL-1R1. In contrast, TIR8 inhibited signaling from the IL-1R complex. Inhibition required the intracellular portion of TIR8 but the extracellular domain was dispensable for blocking activity. Thus, TIR8 is a unique member of the IL-1R family, with a distinct pattern of epithelial expression, including the kidney and mucosae, and an inhibitory function on IL-1 signaling. Copyright John Libbey Eurotext 2003.
Webster, Carl I.; Hatcher, Jon; Burrell, Matthew; Thom, George; Thornton, Peter; Gurrell, Ian; Chessell, Iain
Abstract Neuropathic pain is a major unmet medical need, with only 30% to 35% of patients responding to the current standard of care. The discovery and development of novel therapeutics to address this unmet need have been hampered by poor target engagement, the selectivity of novel molecules, and limited access to the relevant compartments. Biological therapeutics, either monoclonal antibodies (mAbs) or peptides, offer a solution to the challenge of specificity as the intrinsic selectivity of these kinds of molecules is significantly higher than traditional medicinal chemistry–derived approaches. The interleukin-1 receptor system within the spinal cord has been implicated in the amplification of pain signals, and its central antagonism provides relief of neuropathic pain. Targeting the IL-1 system in the spinal cord with biological drugs, however, raises the even greater challenge of delivery to the central compartment. Targeting the transferrin receptor with monoclonal antibodies has proved successful in traversing the endothelial cell–derived blood–brain barrier and delivering proteins to the central nervous system. In this study, we describe a novel construct exemplifying an engineered solution to overcome these challenges. We have generated a novel anti–transferrin receptor-interleukin-1 receptor antagonist fusion that transports to the central nervous system and delivers efficacy in a model of nerve ligation–induced hypersensitivity. Approaches such as these provide promise for novel and selective analgesics that target the central compartment. PMID:28009628
Ishiguro, Tomohito; Takeda, Jun; Fang, Xin; Bronson, Heather; Olson, David M
The role of interleukin-1 (IL-1), a pro-inflammatory cytokine, in parturition is typically noted by changes in its concentrations. Studying the expression of its receptor family, IL-1 receptor (IL-1R) 1, IL-1R2, IL-1R accessory protein (IL-1RAcP), and its predominantly brain isoform, IL-1RAcPb, during late gestation in the uterus in the Long-Evans rat is another. We assessed changes in their mRNA and protein relative abundance in the uterus and compared IL-1RAcP and IL-1RAcPb mRNA abundance in uterus, cervix, ovaries, placenta, and whole blood of Long-Evans rats during late gestation or in RU486 and progesterone-treated dams using quantitative real-time PCR and western immunoblotting. IL-1R1, IL-1RAcP, and IL-1RAcPb mRNA abundance significantly increased in the uterus at delivery whereas IL-1R2 mRNA abundance significantly decreased. IL-1R1 protein increased at term and IL-1R2 protein decreased at term compared to nonpregnant uteri. IL1-RAcPb mRNA abundance was less than IL-1RAcP, but in the lower uterine segment it was the highest of all tissues examined. RU486 stimulated preterm delivery and an increase in IL-1R1 mRNA abundance whereas progesterone administration extended pregnancy and suppressed the increase in IL-1R1. These data suggest that changes in uterine sensitivity to IL-1 occur during late gestation and suggest another level of regulation for the control of delivery. The roles for IL-1RAcP and IL-1RAcPb need to be determined, but may relate to different intracellular signaling pathways.
Gonzalez, Patricia Verónica; Schiöth, Helgi Birgir; Lasaga, Mercedes; Scimonelli, Teresa Nieves
Interleukin-1beta (IL-1beta) significantly influences memory consolidation. Treatments that raise the level of IL-1beta in the brain, given after training, impair contextual fear conditioning. The melanocortin alpha-MSH exerts potent anti-inflammatory actions by physiologically antagonizing the effect of pro-inflammatory cytokines. Five subtypes of melanocortin receptors (MC1R-MC5R) have been identified, with MC3R and MC4R predominating in the central nervous system. The present experiments show that injection of IL-1beta (5 ng/0.25 microl) in dorsal hippocampus up to 15 min after training decreased freezing during the contextual fear test. The treatment with IL-1beta (5 ng/0.25 microl) 12h after conditioning cause amnesia when animals were tested 7 days post training. Thus, our results also demonstrated that IL-1beta can influence persistence of long-term memory. We determined that animals previously injected with IL-1beta can acquire a new contextual fear memory, demonstrating that the hippocampus was not damaged. Treatment with alpha-MSH (0.05 microg/0.25 microl) blocked the effect of IL-1beta on contextual fear memory. Administration of the MC4 receptor antagonist HS014 (0.5 microg/0.25 microl) reversed the effect of alpha-MSH. However, treatment with gamma-MSH (0.5 microg/0.25 microl), an MC3 agonist, did not affect IL-1beta-induced impairment of memory consolidation. These results suggest that alpha-MSH, through central MC4R can inhibit the effect of IL-1beta on memory consolidation.
Matsushima, K.; Akahoshi, T.; Yamada, M.; Furutani, Y.; Oppenheim, J.J.
The properties of an human IL 1 receptor on a human EBV-B line were studied. Purified human IL 1-..beta.. produced by a myelomonocytic cell line (THP-1) was labeled with /sup 125/I by the Bolton-Hunter method without loss of biological activity. Among four EBV-B cell lines tested, a pre-B cell type (VDS-O) specifically bound the most /sup 125/I IL-..beta... Maximal binding was reached within 20 min at 4/sup 0/C. Scatchard analysis of the binding of /sup 125/I-IL 1-..beta.. to VDS-O cells yielded a Kd of 2.4-5.9 x 10/sup -00/ M with 110 to 220 binding (receptor) sites/cell. The binding of /sup 125/I-IL 1-..beta.. to VDS-O cells was inhibited by anti-human IL 1 antibody, natural and recombinant human IL 1-..cap alpha.. as well as IL 1-..beta.., but not by IFN-..cap alpha.., TNF, or LT, suggesting that IL 1-..cap alpha.. and IL 1-..beta.. specifically bind to the same receptor. The mw of the IL 1 receptor on human EBV-B cells was estimated to be 60 Kd both by a chemical crosslinking method and by HPLC gel filtration analysis of solubilized receptor extracted from membranes by a nonionic detergent (CHAPS). The pI of solubilized human IL 1 receptor was 7.3 by HPLC chromatofocusing. Data showing that VDS-O cells proliferate in response to exogenously added IL 1, express IL 1 receptors and also produce IL 1 all support the hypothesis that IL 1 may function as an autocrine signal for B lymphocytes.
Brikos, Constantinos; Wait, Robin; Begum, Shajna; O'Neill, Luke A J; Saklatvala, Jeremy
We investigated the composition of the endogenous ligand-bound type I interleukin-1 (IL-1) receptor (IL-1RI) signaling complex using immunoprecipitation and tandem mass spectrometry. Three proteins with approximate molecular masses of 60 (p60), 36 (p36), and 90 kDa (p90) became phosphorylated after treatment with IL-1. Phosphorylation in vitro of p60 has been reported previously, but its identity was unknown. We showed using tandem mass spectrometry that p60 is identical to interleukin-1 receptor-associated kinase (IRAK)-4. MS also enabled detection of IL-1, IL-1RI, IL-1 receptor accessory protein (IL-1RAcP), and myeloid differentiation primary response protein 88 (MyD88) in the complex. The p60 protein (IRAK-4) was the earliest component of the complex to be phosphorylated. Phosphorylated IRAK-4 from the receptor complex migrated more slowly in SDS-PAGE than its unphosphorylated form as did recombinant IRAK-4 autophosphorylated in vitro. Phosphorylation was restricted to serine and threonine residues. IRAK-4, p36, IL-1RAcP, and MyD88 bound to the liganded receptor within 15 s of activation by IL-1 and remained associated upon prolonged activation, suggesting that the signaling complex is very stable. The p90 phosphoprotein was only transiently associated with the receptor. This behavior and its size were consistent with it being IRAK-1. Our work revealed that liganding of IL-1RI causes its strong and stable association with IL-1RAcP, MyD88, and the previously unidentified protein p60 (IRAK-4). The only component of the IL-1RI signaling complex that dissociated is IRAK-1. Our study is therefore the first detailed description of the endogenous IL-1RI complex.
Radons, Jurgen; Dove, Stefan; Neumann, Detlef; Altmann, Reinhold; Botzki, Alexander; Martin, Michael U; Falk, Werner
The Toll/interleukin 1 (IL-1) receptor family plays an important role in both innate and adaptive immunity. These receptors are characterized by a C-terminal homology motif called the Toll/IL-1 receptor (TIR) domain. A principal function of the TIR domain is mediating homotypic protein-protein interactions in the signal transduction pathway. To suggest interaction sites of TIR domains in the IL-1 receptor complex, we modeled the putative three-dimensional structure of the TIR domain within the co-receptor chain, IL-1 receptor accessory protein. The model was based on homology with the crystal structures of human TLR1 and TLR2. The final structure of the IL-1 receptor accessory protein TIR domain suggests the conserved regions box 1 and 2, including Pro-446, as well as box 3 within the C-terminal alpha-helix as possible protein-protein interaction sites due to their exposure and their electrostatic potential. Pro-446, corresponding to the Pro/His mutation in dominant negative TLR4, is located in the third loop at the outmost edge of the TIR domain and does not play any structural role. Inhibition of IL-1 responsiveness seen after substitution of Pro-446 by charged amino acids is due to the loss of an interaction site for other TIR domains. Amino acids 527-534 as part of the loop close to the conserved box 3 are critical for recruitment of myeloid differentiation factor 88 and to a lesser extent for IL-1 responsiveness. Modeling suggests that native folding of the TIR domain may be approached by the responsive deletion mutants delta528-534 and delta527-533, whereas the C-terminal beta-strand and/or alpha-helix is displaced in the nonresponsive mutant delta527-534.
Radons, Jürgen; Falk, Werner; Dove, Stefan
Interleukin-1 receptor type I (IL-1RI) belongs to a superfamily of proteins characterized by an intracellular Toll/IL-1 receptor (TIR) domain. This domain harbors three conserved regions called boxes 1-3 that play crucial roles in mediating IL-1 responses. Boxes 1 and 2 are considered to be involved in binding of adapter molecules. Amino acids possibly crucial for IL-1RI signaling were predicted via homology models of the IL-1RI TIR domain based on the crystal structure of IL-1RAPL. The role of ten of these residues was investigated by site-directed mutagenesis and a functional luciferase assay reflecting NF-κB activity in transiently transfected Jurkat cells. In particular, the mutants E437K/D438K, E472A/E473A and S465A/S470A/S471A/E472A/E473A showed decreased and the mutant E437A/D438A increased IL-1 responsiveness compared to the mouse IL-1RI wild type. In conclusion, the αC' helix (Q469-E473 in mouse IL-1RI) is probably involved in heterotypic interactions of IL-1RI with IL-1RAcP or MyD88. Copyright © 2015 Elsevier Ltd. All rights reserved.
Liège, S; Layé, S; Li, K S; Moze, E; Neveu, P J
Mice deficient for the IL-1RAcP gene (IL-1RAcP KO) were used to explore the role of IL-1RAcP in physiological functions of brain IL-1beta. Animals were injected i.c.v. with two different doses of recombinant human (rh) IL-1beta: a small one (750 pg) known to induce sickness behavior, and a larger one (50 ng), chosen to counteract the possible loss of affinity of IL-1beta on its receptor. Neuroendocrine and immune parameters were measured 2 h after IL-1 injection. The increase of plasma corticosterone induced by rhIL-1beta in wild-type (WT) mice was not observed in IL-1RAcP KO mice. Likewise, the depression of splenocyte proliferation occurred in WT but not in KO mice. Finally, in opposition to WT mice, plasma levels and brain cortical content of IL-6 in IL-1RAcP KO mice remained unchanged as compared to saline-injected controls. The results clearly demonstrate that IL-1RAcP is necessary for the induction of the main neuroendocrine and immune effects of central IL-1beta.
Lundkvist, J; Sundgren-Andersson, A K; Tingsborg, S; Ostlund, P; Engfors, C; Alheim, K; Bartfai, T; Iverfeldt, K; Schultzberg, M
The interleukin-1 (IL-1) receptor antagonist (IL-1ra) is an endogenous antagonist that blocks the effects of the proinflammatory cytokines IL-1alpha and IL-1beta by occupying the type I IL-1 receptor. Here we describe transgenic mice with astrocyte-directed overexpression of the human secreted IL-1ra (hsIL-1ra) under the control of the murine glial fibrillary acidic protein (GFAP) promoter. Two GFAP-hsIL-1ra strains have been generated and characterized further: GILRA2 and GILRA4. These strains show a brain-specific expression of the hsIL-1ra at the mRNA and protein levels. The hsIL-1ra protein was approximated to approximately 50 ng/brain in cytosolic fractions of whole brain homogenates, with no differences between male and female mice or between the two strains. Furthermore, the protein is secreted, inasmuch as the concentration of hsIL-1ra in the cerebrospinal fluid was 13 (GILRA2) to 28 (GILRA4) times higher in the transgenic mice than in the control animals. To characterize the transgenic phenotype, GILRA mice and nontransgenic controls were injected with recombinant human IL-1beta (central injection) or lipopolysaccharide (LPS, peripheral injection). The febrile response elicited by IL-1beta (50 ng/mouse icv) was abolished in hsIL-1ra-overexpressing animals, suggesting that the central IL-1 receptors were occupied by antagonist. The peripheral LPS injection (25 micrograms/kg ip) triggered a fever in overexpressing and control animals. Moreover, no differences were found in LPS-induced (100 and 1,000 micrograms/kg ip; 1 and 6 h after injection) IL-1beta and IL-6 serum levels between GILRA and wild-type mice. On the basis of these results, we suggest that binding of central IL-1 to central IL-1 receptors is not important in LPS-induced fever or LPS-induced IL-1beta and IL-6 plasma levels.
Leitner, Kirstin; Al Shammary, Mofeedah; McLane, Michael; Johnston, Michael V; Elovitz, Michal A; Burd, Irina
Exposure to intrauterine inflammation, associated with preterm birth, has been linked to a devastating spectrum of neurobehavioral disorders. Mechanisms of this injury are unknown. Using a mouse model of intrauterine inflammation, we have observed a disruption of fetal neuronal morphology along with a marked elevation of interleukin (IL)-1β in the fetal brain and placenta. In this study, we hypothesized that IL-1 plays a key role in perinatal brain injury. Utilizing a mouse model of inflammation-induced preterm birth, we investigated the role of IL-1 in fetal cortical injury as well as preterm birth. In these studies, dams received systemic treatment with IL-1 receptor antagonist prior to administration of intrauterine inflammation. Systemic maternal antagonism of IL-1 improved fetal cortical neuronal injury associated with the exposure to intrauterine inflammation, without affecting the phenotype of preterm birth. IL-1 receptor antagonist blocked activation of neuronal nitric oxide synthase in perinatal cortex, a key enzyme implicated in neurotoxicity. Our data suggest that fetal cortical brain injury and preterm birth may occur by divergent mechanisms. Furthermore, our studies indicate maternal administration of IL-1 receptor antagonist (IL-1RA) blocked neuronal nitric oxide synthase activation observed in the brain cortex and, we speculate, that this alteration in activation leads to demonstrated decreased neurotoxicity. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Pilat, Dominika; Rojewska, Ewelina; Jurga, Agnieszka M; Piotrowska, Anna; Makuch, Wioletta; Przewlocka, Barbara; Mika, Joanna
An interesting research and therapeutic problem is the reduced beneficial efficacy of opioids in the treatment of neuropathic pain. The present study sought to investigate the potential role of IL-1 family members in this phenomenon. We studied the time course of changes in IL-1alpha, IL-1beta, IL-1 receptor type I and IL-1 receptor antagonist mRNA and protein levels experienced by rats after chronic constriction injury (CCI) of the sciatic nerve using qRT-PCR and Western blot analysis. In CCI-exposed rats, spinal levels of IL-1alpha mRNA were slightly downregulated on the 7th day, and protein levels were not changed on the 7th and 14th days. Levels of IL-1 receptor antagonist and IL-1 receptor type I were slightly upregulated in the ipsilateral part of the spinal cord on the 7th and 14th days; however, protein levels were not changed at those time points. Interestingly, we observed that IL-1beta mRNA and protein levels were strongly elevated in the ipsilateral part of the dorsal spinal cord on the 7th and 14th days following CCI. Moreover, in rats exposed to a single intrathecal administration of an IL-1 receptor antagonist (100 ng i.t.) on the 7th and 14th day following CCI, symptoms of neuropathic pain were attenuated, and the analgesic effects of morphine (2.5 µg i.t.) and buprenorphine (2.5 µg i.t.) were enhanced. In summary, restoration of the analgesic activity of morphine and buprenorphine by blockade of IL-1 signaling suggests that increased IL-1beta responses may account for the decreased analgesic efficacy of opioids observed in the treatment of neuropathy.
Anselmo, Achille; Riva, Federica; Gentile, Stefania; Soldani, Cristiana; Barbagallo, Marialuisa; Mazzon, Cristina; Feruglio, Francesca; Polentarutti, Nadia; Somma, Paolo; Carullo, Pierluigi; Angelini, Claudio; Bacci, Monica; Mendolicchio, Grazia Loredana; Voza, Antonio; Nebuloni, Manuela; Mantovani, Alberto; Garlanda, Cecilia
Platelets express functional interleukin-1 receptor-1 (IL-1R1) as well as a repertoire of toll-like receptors (TLRs) involved in platelet activation, platelet-leucocyte reciprocal activation, and immunopathology. IL-1R8, also known as single Ig IL-1-related receptor (SIGIRR) or TIR8, is a member of the IL-1R family that negatively regulates responses to IL-1R family members and TLRs. In the present study, we addressed the expression of IL-1R8 in platelets and megakaryocytes and its role in the control of platelet activation during inflammatory conditions and thromboembolism. Here, we show by flow cytometry analysis, western blot, confocal microscopy, and quantitative real-time polymerase chain reaction that IL-1R8 is expressed on human and mouse platelets at high levels and on megakaryocytes. IL-1R8-deficient mice show normal levels of circulating platelets. Homotypic and heterotypic (platelet-neutrophil) aggregation triggered by Adenosine DiPhosphate (ADP) and IL-1 or lipopolysaccharide (LPS) was increased in IL-1R8-deficient platelets. IL-1R8-deficient mice showed increased soluble P-selectin levels and increased platelet-neutrophil aggregates after systemic LPS administration. Commensal flora depletion and IL-1R1 deficiency abated platelet hyperactivity and the increased platelet/neutrophil aggregation observed in Il1r8(-/-) mice in vitro and in vivo, suggesting a key role of IL-1R8 in regulating platelet TLR and IL-1R1 function. In a mouse model of platelet-dependent pulmonary thromboembolism induced by ADP administration, IL-1R8-deficient mice showed an increased frequency of blood vessel complete obstruction. These results show that platelets, which have a large repertoire of TLRs and IL-1 receptors, express high levels of IL-1R8, which plays a non-redundant function as a regulator of thrombocyte activity in vitro and in vivo. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email
Singh, R.; Wang, B.; Shirvaikar, A.; Khan, S.; Kamat, S.; Schelling, J.R.; Konieczkowski, M.; Sedor, J.R.
IL-1–stimulated mesenchymal cells model molecular mechanisms of inflammation. Binding of IL-1 to the type I IL-1 receptor (IL-1R) clusters a multi-subunit signaling complex at focal adhesion complexes. Since Rho family GTPases coordinately organize actin cytoskeleton and signaling to regulate cell phenotype, we hypothesized that the IL-1R signaling complex contained these G proteins. IL-1 stimulated actin stress fiber formation in serum-starved HeLa cells in a Rho-dependent manner and rapidly activated nucleotide exchange on RhoA. Glutathione S-transferase (GST) fusion proteins, containing either the full-length IL-1R cytosolic domain (GST-IL-1Rcd) or the terminal 68 amino acids of IL-1R required for IL-1–dependent signal transduction, specifically coprecipitated both RhoA and Rac-1, but not p21ras, from Triton-soluble HeLa cell extracts. In whole cells, a small-molecular-weight G protein coimmunoprecipitated by anti–IL-1R antibody was a substrate for C3 transferase, which specifically ADP-ribosylates Rho GTPases. Constitutively activated RhoA, loaded with [γ-32P]GTP, directly interacted with GST-IL-1Rcd in a filter-binding assay. The IL-1Rcd-RhoA interaction was functionally important, since a dominant inhibitory mutant of RhoA prevented IL-1Rcd–directed transcriptional activation of the IL-6 gene. Consistent with our previous data demonstrating that IL-1R–associated myelin basic protein (MBP) kinases are necessary for IL-1–directed gene expression, cellular incorporation of C3 transferase inhibited IL-1R–associated MBP kinase activity both in solution and in gel kinase assays. In summary, IL-1 activated RhoA, which was physically associated with IL-1Rcd and necessary for activation of cytosolic nuclear signaling pathways. These findings suggest that IL-1–stimulated, Rho-dependent cytoskeletal reorganization may cluster signaling molecules in specific architectures that are necessary for persistent cell activation in chronic inflammatory disease
Xu, Q Q; Xu, P; Zhou, J W; Pan, T S; Tuo, R; Ai, K; Yang, D Q
Interleukin-1β (IL-1β) is the prototypic pro-inflammatory cytokine, whose functions are mediated through interaction with its receptors (IL-1R1 and IL-1R2). Herein, we cloned the full-length cDNA and genomic DNA of IL-1β and IL-1R2 in the Asian swamp eel (Monopterus albus). The eel IL-1β cDNA encodes a putative polypeptide of 246 amino acids. The protein sequence includes a typical IL-1 family signature, but lacked an interleukin-converting enzyme cleavage site. The genomic DNA of eel IL-1β was 2520 bp and comprised five exons and four introns. The eel IL-1R2 cDNA encoded a putative propeptide of 423 amino acid residues, comprising a signal peptide, a transmembrane region and two Ig-like domains in the extracellular region. Similar to other vertebrates, the genomic DNA of the eel IL-1R2 has nine exons and eight introns. Real-time PCR analysis indicated that IL-1β and IL-1R2 were constitutively expressed in all tissues, especially in the liver and immune-related organs. After infection with Aeromonas hydrophila, the transcript levels of IL-1β and IL-1R2 were induced in the head kidney and spleen, reaching their highest levels at 6 h post injection. In vitro, IL-1β and IL-1R2 mRNA levels were also upregulated rapidly at 1h post infection with A. hydrophila. Furthermore, acanthocephalan Pallisentis (Neosentis) celatus could induce the expression of both genes in the head kidney and intestine. In infected intestines, the transcript levels of IL-1β and IL-1R2 were increased by 21.4-fold and 20.8-fold, respectively, relative to the control. The present study indicated that IL-1β and IL-1R2 play an important role in inflammation and host defense, especially in the antiacanthocephalan response.
Savenije, Olga E; Mahachie John, Jestinah M; Granell, Raquel; Kerkhof, Marjan; Dijk, F Nicole; de Jongste, Johan C; Smit, Henriëtte A; Brunekreef, Bert; Postma, Dirkje S; Van Steen, Kristel; Henderson, John; Koppelman, Gerard H
Genome-wide association studies identified IL33 and IL-1 receptor-like 1 (IL1RL1)/IL18R1 as asthma susceptibility loci. IL33 and IL1RL1 constitute a single ligand-receptor pathway. In 2 birth cohorts, the Prevalence and Incidence of Asthma and Mite Allergy (PIAMA) study and Avon Longitudinal Study of Parents and Children (ALSPAC), we analyzed associations of longitudinal wheezing phenotypes and asthma with single nucleotide polymorphisms (SNPs) of 8 genes encoding IL-33, IL1RL1, its coreceptor IL1RAcP, its adaptors myeloid differentiation primary response gene 88 (MyD88) and Toll-IL-11 receptor domain containing adaptor protein (TIRAP), and the downstream IL-1 receptor-associated kinase 1, IL-1 receptor-associated kinase 4, and TNF receptor-associated factor 6 (TRAF6). Furthermore, we investigated whether SNPs in this pathway show replicable evidence of gene-gene interaction. Ninety-four SNPs were investigated in 2007 children in the PIAMA study and 7247 children in ALSPAC. Associations with wheezing phenotypes and asthma at 8 years of age were analyzed in each cohort and subsequently meta-analyzed. Gene-gene interactions were assessed through model-based multifactor dimensionality reduction in the PIAMA study, and gene-gene interactions of 10 SNP pairs were further evaluated. Intermediate-onset wheeze was associated with SNPs in several genes in the IL33-IL1RL1 pathway after applying multiple testing correction in the meta-analysis: 2 IL33 SNPs (rs4742170 and rs7037276), 1 IL-1 receptor accessory protein (IL1RAP) SNP (rs10513854), and 1 TRAF6 SNP (rs5030411). Late-onset wheeze was associated with 2 IL1RL1 SNPs (rs10208293 and rs13424006), and persistent wheeze was associated with 1 IL33 SNP (rs1342326) and 1 IL1RAP SNP (rs9290936). IL33 and IL1RL1 SNPs were nominally associated with asthma. Three SNP pairs showed interaction for asthma in the PIAMA study but not in ALSPAC. IL33-IL1RL1 pathway polymorphisms are associated with asthma and specific wheezing
Debets, R; Timans, J C; Churakowa, T; Zurawski, S; de Waal Malefyt, R; Moore, K W; Abrams, J S; O'Garra, A; Bazan, J F; Kastelein, R A
IL-18 is critical in eliciting IFN-gamma production from Th1 cells both in vitro and in vivo. Th1 cells have been implicated in the pathogenesis of autoimmune disorders, making antagonists of IL-18 promising therapeutics. However, specificity and binding characteristics of IL-18R components have only been superficially explored. In this study, we show that IL-1R related protein 1 (IL-1Rrp1) and IL-1R accessory protein-like (IL-1RAcPL) confer responsiveness to IL-18 in a highly specific (no response to other IL-1 ligands) and unique manner (no functional pairing with other IL-1Rs and IL-1R-like molecules). Cotransfection with both receptor components resulted in expression of both low and high affinity binding sites for IL-18 (K:(d) of 11 and 0.4 nM, respectively). We prepared anti-IL-1RAcPL mAb TC30-28E3, which, in contrast to soluble R proteins, effectively inhibited the IL-18-induced activation of NF-kappaB. Quantitative PCR showed that Th1 but not Th2 cells are unique in that they coexpress IL-1Rrp1 and IL-1RAcPL. mAb TC30-28E3 inhibited IL-18-induced production of IFN-gamma by Th1 cells, being at least 10-fold more potent than anti-IL-18 ligand mAb. This study shows that IL-1RAcPL is highly specific to IL-18, is required for high affinity binding of IL-18, and that the anti-IL-1RAcPL mAb TC30-28E3 potently antagonizes IL-18 responses in vitro, providing a rationale for the use of anti-IL-1RAcPL Abs to inhibit Th1-mediated inflammatory pathologies.
Huang, Tzu-Rung; Jou, Shuo-Bin; Chou, Yu-Ju; Yi, Pei-Lu; Chen, Chun-Jen; Chang, Fang-Chia
Sleep disruptions are common in epilepsy patients. Our previous study demonstrates that homeostatic factors and circadian rhythm may mediate epilepsy-induced sleep disturbances when epilepsy occurs at different zeitgeber hours. The proinflammatory cytokine, interleukin-1 (IL-1), is a somnogenic cytokine and may also be involved in epileptogenesis; however, few studies emphasize the effect of IL-1 in epilepsy-induced sleep disruption. We herein hypothesized that IL-1 receptor type 1 (IL-1R1) mediates the pathogenesis of epilepsy and epilepsy-induced sleep disturbances. We determined the role of IL-1R1 by using IL-1R1 knockout (IL-1R1 -/- KO) mice. Our results elucidated the decrease of non-rapid eye movement (NREM) sleep during the light period in IL-1R -/- mice and confirmed the somnogenic role of IL-1R1. Rapid electrical amygdala kindling was performed to induce epilepsy at the particular zeitgeber time (ZT) point, ZT13. Our results demonstrated that seizure thresholds induced by kindling stimuli, such as the after-discharge threshold and successful kindling rates, were not altered in IL-1R -/- mice when compared to those obtained from the wildtype mice (IL-1R +/+ mice). This result suggests that IL-1R1 is not involved in kindling-induced epileptogenesis. During sleep, ZT13 kindling stimulation significantly enhanced NREM sleep during the subsequent 6 h (ZT13-18) in wildtype mice, and sleep returned to the baseline the following day. However, the kindling-induced sleep alteration was absent in the IL-1R -/- KO mice. These results indicate that the IL-1 signal mediates epilepsy-induced sleep disturbance, but dose not participate in kindling-induced epileptogenesis.
Melcher, Karsten; Xu, Yong; Ng, Ley-Moy; Zhou, X. Edward; Soon, Fen-Fen; Chinnusamy, Viswanathan; Suino-Powell, Kelly M; Kovach, Amanda; Tham, Fook S.; Cutler, Sean R.; Li, Jun; Yong, Eu-Leong; Zhu, Jian-Kang; Xu, H. Eric
The phytohormone abscisic acid (ABA) functions through a family of fourteen PYR/PYL receptors, which were identified by resistance to pyrabactin, a synthetic inhibitor of seed germination. ABA activates these receptors to inhibit type 2C protein phosphatases, such as ABI1, yet it remains unclear whether these receptors can be antagonized. Here we demonstrate that pyrabactin is an agonist of PYR1 and PYL1 but is unexpectedly an antagonist of PYL2. Crystal structures of the PYL2-pyrabactin and PYL1-pyrabactin-ABI1 complexes reveal the mechanism responsible for receptor-selective activation and inhibition, which enables us to design mutations that convert PYL1 to a pyrabactin-inhibited receptor and PYL2 to a pyrabactin-activated receptor and to identify new pyrabactin-based ABA receptor agonists. Together, our results establish a new concept of ABA receptor antagonism, illustrate its underlying mechanisms and provide a rational framework for discovering novel ABA receptor ligands.
Ali, Abukar; Na, Manli; Svensson, Mattias N. D.; Magnusson, Malin; Welin, Amanda; Schwarze, Jan-Christoph; Mohammad, Majd; Josefsson, Elisabet; Pullerits, Rille; Jin, Tao
Background Interleukin-1 receptor antagonist (IL-1Ra) is the primary therapy against autoinflammatory syndromes with robust efficacy in reducing systemic inflammation and associated organ injury. However, patients receiving IL-1Ra might be at increased risk of acquiring serious infections. Aims To study whether IL-1Ra treatment deteriorates Staphylococcus aureus (S. aureus) septic arthritis and sepsis in mice. Method NMRI mice were treated with anakinra (IL-1Ra) daily for 7 days before intravenous inoculation with S. aureus strain Newman in both arthritogenic and lethal doses. The clinical course of septic arthritis, histopathological and radiological changes of the joints, as well as the mortality were compared between IL-1Ra treated and control groups. Results IL-1Ra treated mice developed more frequent and severe clinical septic arthritis. Also, the frequency of polyarthritis was significantly higher in the mice receiving IL-1Ra therapy. In line with the data from clinical arthritis, both histological and radiological signs of septic arthritis were more pronounced in IL-1Ra treated group compared to controls. Importantly, the mortality of IL-1Ra treated mice was significantly higher than PBS treated controls. Conclusion IL-1Ra treatment significantly aggravated S. aureus induced septic arthritis and increased the mortality in these mice. PMID:26135738
Gambino, Frédéric; Pavlowsky, Alice; Béglé, Aurélie; Dupont, Jean-Luc; Bahi, Nadia; Courjaret, Raphael; Gardette, Robert; Hadjkacem, Hassen; Skala, Henriette; Poulain, Bernard; Chelly, Jamel; Vitale, Nicolas; Humeau, Yann
Null mutations in the IL1-receptor accessory protein-like 1 gene (IL1RAPL1) are responsible for an inherited X-linked form of cognitive impairment. IL1RAPL1 protein physically interacts with neuronal calcium sensor-1 (NCS-1), but the functional impact of the IL1RAPL1/NCS-1 interaction remains unknown. Here, we demonstrate that stable expression of IL1RAPL1 in PC12 cells induces a specific silencing of N-type voltage-gated calcium channels (N-VGCC) activity that explains a secretion deficit observed in these IL1RAPL1 cells. Importantly, this modulation of VGCC activity is mediated by NCS-1. Indeed, a specific loss-of-function of N-VGCC was observed in PC12 cells overexpressing NCS-1, and a total recovery of N-VGCC activity was obtained by a down-regulation of NCS-1 in IL1RAPL1 cells. The functional relevance of the interaction between IL1RAPL1 and NCS-1 was also suggested by the reduction of neurite elongation observed in nerve growth factor (NGF)-treated IL1RAPL1 cells, a phenotype rescued by NCS-1 inactivation. Because both proteins are highly expressed in neurons, these results suggest that IL1RAPL1-related mental retardation could result from a disruption of N-VGCC and/or NCS-1-dependent synaptic and neuronal activities.
Benny Klimek, Margaret E.; Sali, Arpana; Rayavarapu, Sree; Van der Meulen, Jack H.; Nagaraju, Kanneboyina
Duchenne muscular dystrophy (DMD) is an X-linked muscle disease caused by mutations in the dystrophin gene. The pathology of DMD manifests in patients with progressive muscle weakness, loss of ambulation and ultimately death. One of the characteristics of DMD is muscle inflammation, and dystrophin-deficient skeletal muscles produce higher levels of the pro-inflammatory cytokine interleukin 1β (IL-1β) in response to toll like receptor (TLR) stimulation compared to controls; therefore, blocking the IL-1β pathway could improve the disease phenotype in mdx mice, a mouse model of DMD. Kineret® or IL-1Ra is a recombinant IL-1 receptor antagonist approved by the FDA for treating rheumatoid arthritis. To determine the efficacy of IL-1Ra in a DMD model, we administered subcutaneous injections of saline control or IL-1Ra (25 mg/kg/day) to mdx mice daily for 45 days beginning at 5 weeks of age. Functional and histological parameters were measured at the conclusion of the study. IL-1Ra only partially inhibited this signaling pathway in this study; however, there were still interesting observations to be noted. For example, although not significantly changed, splenocytes from the IL-1Ra-treated group secreted less IL-1β after LPS stimulation compared to control mice indicating a blunted response and incomplete inhibition of the pathway (37% decrease). In addition, normalized forelimb grip strength was significantly increased in IL-1Ra-treated mice. There were no changes in EDL muscle-specific force measurements, histological parameters, or motor coordination assessments in the dystrophic mice after IL-1Ra treatment. There was a significant 27% decrease in the movement time and total distance traveled by the IL-1Ra treated mice, correlating with previous studies examining effects of IL-1 on behavior. Our studies indicate partial blocking of IL-1β with IL-1Ra significantly altered only a few behavioral and strength related disease parameters; however, treatment with
Khan, Javed A; Brint, Elizabeth K; O'Neill, Luke A J; Tong, Liang
The Toll/interleukin-1 receptor (TIR) domain is conserved in the intracellular regions of Toll-like receptors (TLRs) and interleukin-1 receptors (IL-1Rs) as well as in several cytoplasmic adapter molecules. This domain has crucial roles in signal transduction by these receptors for host immune response. Here we report the crystal structure at 2.3-A resolution of the TIR domain of human IL-1RAPL, the first structure of a TIR domain of the IL-1R superfamily. There are large structural differences between this TIR domain and that of TLR1 and TLR2. Helix alphaD in IL-1RAPL is almost perpendicular to its equivalent in TLR1 or TLR2. The BB loop contains a hydrogen bond unique to IL-1RAPL between Thr residues at the 8th and 10th positions. The structural and sequence diversity among these domains may be important for specificity in the signal transduction by these receptors. A dimer of the TIR domain of IL-1RAPL is observed in the crystal, although this domain is monomeric in solution. Residues in the dimer interface are mostly unique to IL-1RAPL, which is consistent with the distinct functional roles of this receptor. Our functional studies show IL-1RAPL can activate JNK but not the ERK or the p38 MAP kinases, whereas its close homolog, TIGIRR, cannot activate JNK. Deletion mutagenesis studies show that the activation of JNK by IL-1RAPL does not depend on the integrity of its TIR domain, suggesting a distinct mechanism of signaling through this receptor.
Conti, P; Bartle, L; Barbacane, R C; Reale, M; Sipe, J D
Infections, trauma and inflammatory processes induce a host response with increases in a large group of structurally and functionally diverse plasma proteins. Parental administration of foreign proteins also induce an increase in plasma fibrinogen. Interleukin-6 (IL-6) is a monocyte-derived mediator and has regulatory effects on acute phase protein genes which result in the induction of fibrinogen synthesis in primary hepatocytes, while the addition of interleukin-1 (IL-1) exerts a negative modulating influence on the IL-6-stimulated fibrinogen. In order to understand the mechanisms by which IL-1 inhibits IL-6-stimulated fibrinogen transcription and translation, and since IL-1 is believed to act through PGE2 stimulation, we have studied the influence of PGE2 in IL-6 or IL-1, alone and in combination, on Fg mRNA expression (by Northern blot analysis) and the influence of PGE2, indomethacin, and arachidonic acid on Fg secretion. Moreover, since human recombinant interleukin-1 receptor antagonist (hrIL-1ra) is a strong inhibitor of IL-1 induced IL-1 transcription and translation and has an inhibitory effect on PGE2, we have studied the effects of IL-1ra on the down-regulation of IL-6 stimulated fibrinogen by IL-1, using an Fg ELISA method.(ABSTRACT TRUNCATED AT 250 WORDS)
McMahan, C J; Slack, J L; Mosley, B; Cosman, D; Lupton, S D; Brunton, L L; Grubin, C E; Wignall, J M; Jenkins, N A; Brannan, C I
cDNA clones corresponding to an Mr approximately 80,000 receptor (type I receptor) for interleukin-1 (IL-1) have been isolated previously by mammalian expression. Here, we report the use of an improved expression cloning method to isolate human and murine cDNA clones encoding a second type (Mr approximately 60,000) of IL-1 receptor (type II receptor). The mature type II IL-1 receptor consists of (i) a ligand binding portion comprised of three immunoglobulin-like domains; (ii) a single transmembrane region; and (iii) a short cytoplasmic domain of 29 amino acids. This last contrasts with the approximately 215 amino acid cytoplasmic domain of the type I receptor, and suggests that the two IL-1 receptors may interact with different signal transduction pathways. The type II receptor is expressed in a number of different tissues, including both B and T lymphocytes, and can be induced in several cell types by treatment with phorbol ester. Both IL-1 receptors appear to be well conserved in evolution, and map to the same chromosomal location. Like the type I receptor, the human type II IL-1 receptor can bind all three forms of IL-1 (IL-1 alpha, IL-1 beta and IL-1ra). Vaccinia virus contains an open reading frame bearing strong resemblance to the type II IL-1 receptor. Images PMID:1833184
Transforming growth factor beta (TGF-beta) acts as a potent inhibitor of the growth and functions of lymphoid and hemopoietic progenitor cells. Cell proliferation depends not only on the presence of growth factors, but also on the development of specific receptor-signal transducing complexes. We therefore investigated whether the inhibitory actions of TGF-beta could be mediated by inhibition of growth factor receptors. TGF-beta inhibited the constitutive level of interleukin 1 receptor (IL-1R) expression on several murine lymphoid and myeloid progenitor cell lines, as well as IL-1R expression induced by interleukin 3 (IL-3) on normal murine and human bone marrow cells. Furthermore, treatment of bone marrow progenitor cells with TGF-beta concomitantly inhibited the ability of IL-1 to promote high proliferative potential (HPP) colony formation as well as blocked IL-1- induced IL-2 production by EL-4 6.1 cells. These findings provide the first evidence that the inhibitory action of TGF-beta on the growth and functional activities of hematopoietic and T cells is associated with a reduction in the cell surface receptor expression for IL-1. PMID:2143773
Verhein, Kirsten C; Jacoby, David B; Fryer, Allison D
Ozone exposure in the lab and environment causes airway hyperreactivity lasting at least 3 days in humans and animals. In guinea pigs 1 day after ozone exposure, airway hyperreactivity is mediated by eosinophils that block neuronal M(2) muscarinic receptor function, thus increasing acetylcholine release from airway parasympathetic nerves. However, mechanisms of ozone-induced airway hyperreactivity change over time, so that depleting eosinophils 3 days after ozone makes airway hyperreactivity worse rather than better. Ozone exposure increases IL-1beta in bone marrow, which may contribute to acute and chronic airway hyperreactivity. To test whether IL-1beta mediates ozone-induced airway hyperreactivity 1 and 3 days after ozone exposure, guinea pigs were pretreated with an IL-1 receptor antagonist (anakinra, 30 mg/kg, intraperitoneally) 30 minutes before exposure to filtered air or to ozone (2 ppm, 4 h). One or three days after exposure, airway reactivity was measured in anesthetized guinea pigs. The IL-1 receptor antagonist prevented ozone-induced airway hyperreactivity 3 days, but not 1 day, after ozone exposure. Ozone-induced airway hyperreactivity was vagally mediated, since bronchoconstriction induced by intravenous acetylcholine was not changed by ozone. The IL-1 receptor antagonist selectively prevented ozone-induced reduction of eosinophils around nerves and prevented ozone-induced deposition of extracellular eosinophil major basic protein in airways. These data demonstrate that IL-1 mediates ozone-induced airway hyperreactivity at 3 days, but not 1 day, after ozone exposure. Furthermore, preventing hyperreactivity was accompanied by decreased eosinophil major basic protein deposition within the lung, suggesting that IL-1 affects eosinophil activation 3 days after ozone exposure.
Verhein, Kirsten C.; Jacoby, David B.; Fryer, Allison D.
Ozone exposure in the lab and environment causes airway hyperreactivity lasting at least 3 days in humans and animals. In guinea pigs 1 day after ozone exposure, airway hyperreactivity is mediated by eosinophils that block neuronal M2 muscarinic receptor function, thus increasing acetylcholine release from airway parasympathetic nerves. However, mechanisms of ozone-induced airway hyperreactivity change over time, so that depleting eosinophils 3 days after ozone makes airway hyperreactivity worse rather than better. Ozone exposure increases IL-1β in bone marrow, which may contribute to acute and chronic airway hyperreactivity. To test whether IL-1β mediates ozone-induced airway hyperreactivity 1 and 3 days after ozone exposure, guinea pigs were pretreated with an IL-1 receptor antagonist (anakinra, 30 mg/kg, intraperitoneally) 30 minutes before exposure to filtered air or to ozone (2 ppm, 4 h). One or three days after exposure, airway reactivity was measured in anesthetized guinea pigs. The IL-1 receptor antagonist prevented ozone-induced airway hyperreactivity 3 days, but not 1 day, after ozone exposure. Ozone-induced airway hyperreactivity was vagally mediated, since bronchoconstriction induced by intravenous acetylcholine was not changed by ozone. The IL-1 receptor antagonist selectively prevented ozone-induced reduction of eosinophils around nerves and prevented ozone-induced deposition of extracellular eosinophil major basic protein in airways. These data demonstrate that IL-1 mediates ozone-induced airway hyperreactivity at 3 days, but not 1 day, after ozone exposure. Furthermore, preventing hyperreactivity was accompanied by decreased eosinophil major basic protein deposition within the lung, suggesting that IL-1 affects eosinophil activation 3 days after ozone exposure. PMID:18617681
Gu, Yi-feng; Fang, Yu; Jin, Yang; Dong, Wei-ren; Xiang, Li-xin; Shao, Jian-zhong
Toll-IL-1R (TIR) family members play crucial roles in a variety of defense, inflammatory, injury, and stress responses. Although they have been widely investigated in mammals, little is known about TIRs in ancient vertebrates. In this study, we report a novel double Ig IL-1R related molecule (DIGIRR) from three model fish (Tetraodon nigroviridis, Gasterosteus aculeatus, and Takifugu rubripes), adding a previously unknown homolog to the TIR family. This DIGIRR molecule contains two Ig-like domains in the extracellular region, one Arg-Tyr-mutated TIR domain in the intracellular region, and a unique subcellular distribution within the Golgi apparatus. These characteristics distinguish DIGIRR from other known family members. In vitro injection of DIGIRR into zebrafish embryos dramatically inhibited LPS-induced and IL-1β-induced NF-κB activation. Moreover, in vivo knockdown of DIGIRR by small interfering RNA significantly promoted the expression of IL-1β-stimulated proinflammatory cytokines (IL-6 and IL-1β) in DIGIRR-silenced liver and kidney tissues and in leukocytes. These results strongly suggest that DIGIRR is an important negative regulator of LPS-mediated and IL-1β-mediated signaling pathways and inflammatory responses. The Arg-Tyr-mutated site disrupted the signal transduction ability of DIGIRR TIR. Evolutionally, we propose a hypothesis that DIGIRR and single Ig IL-1R related molecule (SIGIRR) might originate from a common ancient IL-1R-like molecule that lost one (in DIGIRR) or two (in SIGIRR) extracellular Ig-like domains and intracellular Ser and Arg-Tyr amino acids. DIGIRR might be an evolutionary "transitional molecule" between IL-1R and SIGIRR, representing a shift from a potent receptor to a negative regulator. These results help define the evolutionary history of TIR family members and their associated signaling pathways and mechanisms.
Melcher, Karsten; Xu, Yong; Ng, Ley-Moy; Zhou, X. Edward; Soon, Fen-Fen; Chinnusamy, Viswanathan; Suino-Powell, Kelly M.; Kovach, Amanda; Tham, Fook S.; Cutler, Sean R.; Li, Jun; Yong, Eu-Leong; Zhu, Jian-Kang; Xu, H. Eric
The phytohormone abscisic acid (ABA) functions through a family of fourteen PYR/PYL receptors, which were identified by resistance to pyrabactin, a synthetic inhibitor of seed germination. ABA activates these receptors to inhibit type 2C protein phosphatases, such as ABI1, yet it remains unclear whether these receptors can be antagonized. Here we demonstrate that pyrabactin is an agonist of PYR1 and PYL1, but unexpectedly an antagonist of PYL2. Crystal structures of the PYL2–pyrabactin and PYL1–pyrabactin–ABI1 complexes reveal the mechanism responsible for receptor-selective activation and inhibition, which enables us to design mutations that convert PYL1 to a pyrabactin-inhibited receptor and PYL2 to a pyrabactin-activated receptor, and to identify new pyrabactin-based ABA receptor agonists. Together, our results establish a new concept of ABA receptor antagonism, illustrate its underlying mechanisms, and provide a rational framework for discovering novel ABA receptor ligands. PMID:20729862
Lee, Siyoung; Kim, Eunsom; Jhun, Hyunjhung; Hong, Jaewoo; Kwak, Areum; Jo, Seunghyun; Bae, Suyoung; Lee, Jongho; Kim, Busun; Lee, Jungmin; Youn, Sulah; Kim, Somi; Kim, Miyeon; Kim, Hyunwoo; Lee, Youngmin; Choi, Dong-Ki; Kim, Yong-Sung; Kim, Soohyun
Although it has been established that diabetes increases susceptibility to infections, the role of insulin (INS) in the immune response is unknown. Here, we investigated the immunological function of INS. Proinsulin dimer (pINSd) was a potent immune stimulus that induced inflammatory cytokines, but mature INS was unable to induce an immune response. An affinity-purified rabbit polyclonal antibody raised against mature IL-1α recognized IL-1α and pINS but failed to detect mature INS and IL-1β. Analysis of the pINS sequence revealed the existence of an INS/IL-1α motif in the C-peptide of pINS. Surprisingly, the INS/IL-1α motif was recognized by monoclonal antibody raised against IL-1α. Deleting the INS/IL-1α motif in pINSd and IL-1α changed their activities. To investigate the pINSd receptor, the reconstitution of IL-1 receptor 1 (IL-1R1) in Wish cells restored pINSd activity that was reversed by an IL-1R antagonist. These data suggested that pINSd needs IL-1R1 for inflammatory cytokine induction. Mouse embryo fibroblast cells of IL-1R1-deficient mice further confirmed that pINSd promotes immune responses through IL-1R1. PMID:27226621
Li, Suzhao; Neff, C. Preston; Barber, Kristina; Hong, Jaewoo; Luo, Yuchun; Azam, Tania; Palmer, Brent E.; Fujita, Mayumi; Garlanda, Cecilia; Mantovani, Alberto; Kim, Soohyun; Dinarello, Charles Anthony
Similar to IL-1α and IL-33, IL-1 family member IL-37b translocates to the nucleus and is associated with suppression of innate and adaptive immunity. Here we demonstrate an extracellular function of the IL-37 precursor and a processed form. Recombinant IL-37 precursor reduced LPS-induced IL-6 by 50% (P < 0.001) in highly inflammatory human blood-derived M1 differentiated macrophages derived from selective subjects but not M2 macrophages. In contrast, a neutralizing monoclonal anti–IL-37 increased LPS-induced IL-6, TNFα and IL-1β (P < 0.01). The suppression by IL-37 was consistently observed at low picomolar but not nanomolar concentrations. Whereas LPS induced a 12-fold increase in TNFα mRNA, IL-37 pretreatment decreased the expression to only 3-fold over background (P < 0.01). Mechanistically, LPS-induced p38 and pERK were reduced by IL-37. Recombinant IL-37 bound to the immobilized ligand binding α-chain of the IL-18 receptor as well as to the decoy receptor IL-1R8. In M1 macrophages, LPS increased the surface expression of IL-1R8. Compared with human blood monocytes, resting M1 cells express more surface IL-1R8 as well as total IL-1R8; there was a 16-fold increase in IL-1R8 mRNA levels when pretreated with IL-37. IL-37 reduced LPS-induced TNFα and IL-6 by 50–55% in mouse bone marrow-derived dendritic cells, but not in dendritic cells derived from IL-1R8–deficient mice. In mice subjected to systemic LPS-induced inflammation, pretreatment with IL-37 reduced circulating and organ cytokine levels. Thus, in addition to a nuclear function, IL-37 acts as an extracellular cytokine by binding to the IL-18 receptor but using the IL-1R8 for its anti-inflammatory properties. PMID:25654981
Li, Suzhao; Neff, C Preston; Barber, Kristina; Hong, Jaewoo; Luo, Yuchun; Azam, Tania; Palmer, Brent E; Fujita, Mayumi; Garlanda, Cecilia; Mantovani, Alberto; Kim, Soohyun; Dinarello, Charles Anthony
Similar to IL-1α and IL-33, IL-1 family member IL-37b translocates to the nucleus and is associated with suppression of innate and adaptive immunity. Here we demonstrate an extracellular function of the IL-37 precursor and a processed form. Recombinant IL-37 precursor reduced LPS-induced IL-6 by 50% (P < 0.001) in highly inflammatory human blood-derived M1 differentiated macrophages derived from selective subjects but not M2 macrophages. In contrast, a neutralizing monoclonal anti-IL-37 increased LPS-induced IL-6, TNFα and IL-1β (P < 0.01). The suppression by IL-37 was consistently observed at low picomolar but not nanomolar concentrations. Whereas LPS induced a 12-fold increase in TNFα mRNA, IL-37 pretreatment decreased the expression to only 3-fold over background (P < 0.01). Mechanistically, LPS-induced p38 and pERK were reduced by IL-37. Recombinant IL-37 bound to the immobilized ligand binding α-chain of the IL-18 receptor as well as to the decoy receptor IL-1R8. In M1 macrophages, LPS increased the surface expression of IL-1R8. Compared with human blood monocytes, resting M1 cells express more surface IL-1R8 as well as total IL-1R8; there was a 16-fold increase in IL-1R8 mRNA levels when pretreated with IL-37. IL-37 reduced LPS-induced TNFα and IL-6 by 50-55% in mouse bone marrow-derived dendritic cells, but not in dendritic cells derived from IL-1R8-deficient mice. In mice subjected to systemic LPS-induced inflammation, pretreatment with IL-37 reduced circulating and organ cytokine levels. Thus, in addition to a nuclear function, IL-37 acts as an extracellular cytokine by binding to the IL-18 receptor but using the IL-1R8 for its anti-inflammatory properties.
Ali, Shafaqat; Huber, Michael; Kollewe, Christian; Bischoff, Stephan C; Falk, Werner; Martin, Michael U
Lack of the IL-1 receptor accessory protein (IL-1RAcP) abrogates responses to IL-33 and IL-1 in the mouse thymoma clone EL-4 D6/76 cells. Reconstitution with full-length IL-1RAcP is sufficient to restore responsiveness to IL-33 and IL-1. IL-33 activates IL-1 receptor-associated kinase-1, cJun-N-terminal kinase, and the NF-kappaB pathway in an IL-1RAcP-dependent manner and results in IL-2 release. IL-33 is able to induce the release of proinflammatory cytokines in bone marrow-derived (BMD) mast cells, indicating that IL-33 may have a proinflammatory potential like its relatives IL-1 and IL-18, in addition to its Th2-skewing properties in the adaptive response described previously. Blocking of murine IL-1RAcP with the neutralizing antibody 4C5 inhibits response of mouse thymoma cells and BMD mast cells to IL-33. The interaction of either membrane-bound or soluble forms of IL-1RAcP and IL-33Ralpha-chain depends on the presence of IL-33, as demonstrated by coimmunoprecipitation assays. These data demonstrate that IL-1RAcP is indispensable for IL-33 signaling. Furthermore, they suggest that IL-1RAcP is used by more than one alpha-chain of the IL-1 receptor family and thus may resemble a common beta-chain of that family.
Zhang, Rui-Xin; Li, Aihui; Liu, Bing; Wang, Linbo; Ren, Ke; Zhang, Haiqing; Berman, Brian M; Lao, Lixing
Although it has been shown that pro-inflammatory cytokines such as interleukin-1beta (IL-1beta) facilitate perception of noxious inputs at the spinal level, the mechanisms have not been understood. This study determined the cell type that produces IL-1beta, the co-localization of IL-1 receptor type I (IL-1RI) and Fos and NR1 in the spinal cord, and the effects of IL-1 receptor antagonist (IL-1ra) on NR1 phosphorylation and hyperalgesia in a rat model of inflammatory pain. Phosphorylation of NR1, an essential subunit of the NMDA receptor (NMDAR), is known to modulate NMDAR activity and facilitate pain. Hyperalgesia was induced by injecting complete Freund's adjuvant (CFA, 0.08ml, 40microg Mycobacterium tuberculosis) into one hind paw of each rat. Paw withdrawal latency (PWL) was tested before CFA (-48h) for baseline and 2 and 24h after CFA to assess hyperalgesia. IL-1ra was given (i.t.) 24h before CFA to block the action of basal IL-1beta and 2h prior to each of two PWL tests to block CFA-induced IL-1beta. Spinal cords were removed for double immunostaining of IL-1beta/neuronal marker and IL-1beta/glial cell markers, IL-1RI/Fos and IL-1RI/NR1, and for Western blot to measure NR1 phosphorylation. The data showed that: (1) astrocytes produce IL-1beta, (2) IL-1RI is localized in Fos- and NR1-immunoreactive neurons within the spinal dorsal horn, and (3) IL-1ra at 0.01mg/rat significantly increased PWL (P<0.05) and inhibited NR1 phosphorylation compared to saline control. The results suggest that spinal IL-1beta is produced by astrocytes and enhances NR1 phosphorylation to facilitate inflammatory pain.
Bawolak, Marie-Thérèse; Marceau, François
Zaltoprofen is a nonsteroidal antiinflammatory drug that has been proposed to inhibit with some selectivity the nociception mediated by the bradykinin (BK) B(2) receptor. In order to test the predictive power of this claim, we applied the drug to vascular smooth muscle assays previously found useful to characterize B(2) receptor antagonists (contractility, human isolated umbilical vein) or B(1) receptor antagonists (contraction, rabbit aorta; relaxation, rabbit mesenteric artery). Zaltoprofen (up to 30 microM) failed to antagonize BK or des-Arg(9)-BK-induced contraction in the umbilical vein and aorta, respectively. The drug (1 microM) abated des-Arg(9)-BK-induced, prostaglandin-mediated relaxation of the precontracted mesenteric artery, consistent with its known activity as a cyclooxygenase (COX) inhibitor. However, zaltoprofen (10 microM) did not inhibit kinin-stimulated phospholipase A(2) activity in HEK 293 cells expressing recombinant forms of the rabbit B(1) or B(2) receptors. Nonpeptide antagonists of either receptor subtype were active in this respect. The results do not support that zaltoprofen, a COX inhibitor, antagonizes kinin receptors or influences their signaling with selectivity in the tested systems.
Seo, Heewon; Choi, Yohan; Shim, Jangsoo; Choi, Youngsok; Ka, Hakhyun
During the implantation period, the porcine conceptus secretes interleukin-1beta (IL1B) that may be involved in the establishment of pregnancy in pigs. However, the regulatory mechanism for IL1B receptor expression and the function of IL1B in the uterine endometrium are not well elucidated. In this study, we determined IL1B receptor expression in the uterine endometrium of pigs during pregnancy. IL1B receptor subtypes, IL1 receptor type I (IL1R1) and IL1 receptor accessory protein (IL1RAP) were expressed in the uterine endometrium with the expression being most abundant on Day 12 of pregnancy primarily in the luminal and glandular epithelial cells. Expression of IL1R1 mRNA increased in response to IL1B in a dose-dependent manner, and expression of IL1RAP mRNA increased in response to both IL1B and estradiol, indicating that expression of endometrial IL1B receptors was regulated cooperatively by IL1B and estrogen of conceptus origin. During the peri-implantation period, the porcine uterine endometrium actively synthesizes and secretes prostaglandins (PGs). IL1B increased expression of PTGS1 and PTGS2 genes that are rate-limiting for PG synthesis in the uterine endometrium. Collectively, the results indicated that IL1B regulates expression of IL1R1 and IL1RAP and stimulates expression of PTGS1 and PTGS2 that are considered to be the most rate-limiting enzymes for endometrial synthesis of PGs during the peri-implantation period of pregnancy in pigs.
Nasser, Suzanne A; El-Mas, Mahmoud M
Since the discovery of the endothelin system in 1988, it has been implicated in numerous physiological and pathological phenomena. In the cardiovascular system, endothelin-1 (ET-1) acts through intracellular pathways of two endothelin receptors (ETA and ETB) located mainly on smooth muscle and endothelial cells to regulate vascular tone and provoke mitogenic and proinflammatory reactions. The endothelin ETA receptor is believed to play a pivotal role in the pathogenesis of several cardiovascular disease including systemic hypertension, pulmonary arterial hypertension (PAH), dilated cardiomyopathy, and diabetic microvascular dysfunction. Growing evidence from recent experimental and clinical studies indicates that the blockade of endothelin receptors, particularly the ETA subtype, grasps promise in the treatment of major cardiovascular pathologies. The simultaneous blockade of endothelin ETB receptors might not be advantageous, leading possibly to vasoconstriction and salt and water retentions. This review summarizes the role of ET-1 in cardiovascular modulation and the therapeutic potential of endothelin receptor antagonism.
Jesus, Adriana A.; Osman, Mazen; Silva, Clovis A.; Kim, Peter W.; Pham, Tuyet-Hang; Gadina, Massimo; Yang, Barbara; Bertola, Débora R.; Carneiro-Sampaio, Magda; Ferguson, Polly J.; Renshaw, Blair R.; Schooley, Ken; Brown, Michael; Al-Dosari, Asma; Al-Alami, Jamil; Sims, John E.; Goldbach-Mansky, Raphaela; El-Shanti, Hatem
Objective Monogenic autoinflammatory diseases are disorders of Mendelian inheritance that are characterized by mutations in genes that regulate innate immunity and whose typical features are systemic inflammation without high-titer autoantibodies or antigen-specific T cells. Skin and bone inflammation in the newborn period have been described in 3 of these autoinflammatory disorders: neonatal-onset multisystem inflammatory disease, Majeed syndrome, and deficiency of interleukin-1 (IL-1) receptor antagonist (DIRA) syndrome. This study was undertaken to present the characteristics of the DIRA syndrome in 2 cases from Brazil, and describe a novel mutation in IL1RN. Methods Two unrelated Brazilian patients were evaluated for the clinical signs and symptoms of these 3 disorders, and peripheral blood samples were assessed for mutations in NLRP3, LPIN2, and IL1RN by DNA resequencing analysis. A mutation in IL1RN that encodes a mutant protein was identified, and the expression and function of this mutant protein were compared to those of the wild-type protein. Results Both patients presented with pustular dermatitis resembling generalized pustular psoriasis, recurrent multifocal aseptic osteomyelitis, and elevation in the levels of acute-phase reactants, all of which are features most consistent with the DIRA syndrome. Chronic lung disease was observed in 1 of the patients, and jugular venous thrombosis was observed in the other patient. Both patients showed a partial response to corticosteroid therapy, and 1 patient experienced an initial improvement of dermatitis with the use of acitretin. Both patients were homozygous for a novel 15-bp (in-frame) deletion on the IL1RN gene. The mutated protein expressed in vitro had no affinity with the IL-1 receptor, and stimulation of the patients' cells with recombinant human IL-1α or IL-1β led to oversecretion of proinflammatory cytokines, similar to the findings obtained in previously reported patients. Conclusion The presence of
Sugawara, Reiko; Lee, Eun-Jung; Jang, Min Seong; Jeun, Eun-Ji; Hong, Chun-Pyo; Kim, Jung-Hwan; Park, Areum; Yun, Chang Ho; Hong, Sung-Wook; Kim, You-Me; Seoh, Ju-Young; Jung, YunJae; Surh, Charles D; Miyasaka, Masayuki; Yang, Bo-Gie; Jang, Myoung Ho
Eosinophils play proinflammatory roles in helminth infections and allergic diseases. Under steady-state conditions, eosinophils are abundantly found in the small intestinal lamina propria, but their physiological function is largely unexplored. In this study, we found that small intestinal eosinophils down-regulate Th17 cells. Th17 cells in the small intestine were markedly increased in the ΔdblGATA-1 mice lacking eosinophils, and an inverse correlation was observed between the number of eosinophils and that of Th17 cells in the small intestine of wild-type mice. In addition, small intestinal eosinophils suppressed the in vitro differentiation of Th17 cells, as well as IL-17 production by small intestinal CD4(+)T cells. Unlike other small intestinal immune cells or circulating eosinophils, we found that small intestinal eosinophils have a unique ability to constitutively secrete high levels of IL-1 receptor antagonist (IL-1Ra), a natural inhibitor of IL-1β. Moreover, small intestinal eosinophils isolated from IL-1Ra-deficient mice failed to suppress Th17 cells. Collectively, our results demonstrate that small intestinal eosinophils play a pivotal role in the maintenance of intestinal homeostasis by regulating Th17 cells via production of IL-1Ra.
Tomasoni, Romana; Morini, Raffaella; Lopez-Atalaya, Jose P; Corradini, Irene; Canzi, Alice; Rasile, Marco; Mantovani, Cristina; Pozzi, Davide; Garlanda, Cecilia; Mantovani, Alberto; Menna, Elisabetta; Barco, Angel; Matteoli, Michela
Inflammation modifies risk and/or severity of a variety of brain diseases through still elusive molecular mechanisms. Here we show that hyperactivation of the interleukin 1 pathway, through either ablation of the interleukin 1 receptor 8 (IL-1R8, also known as SIGIRR or Tir8) or activation of IL-1R, leads to up-regulation of the mTOR pathway and increased levels of the epigenetic regulator MeCP2, bringing to disruption of dendritic spine morphology, synaptic plasticity and plasticity-related gene expression. Genetic correction of MeCP2 levels in IL-1R8 KO neurons rescues the synaptic defects. Pharmacological inhibition of IL-1R activation by Anakinra corrects transcriptional changes, restores MeCP2 levels and spine plasticity and ameliorates cognitive defects in IL-1R8 KO mice. By linking for the first time neuronal MeCP2, a key player in brain development, to immune activation and demonstrating that synaptic defects can be pharmacologically reversed, these data open the possibility for novel treatments of neurological diseases through the immune system modulation. DOI: http://dx.doi.org/10.7554/eLife.21735.001 PMID:28347403
Tomasoni, Romana; Morini, Raffaella; Lopez-Atalaya, Jose P; Corradini, Irene; Canzi, Alice; Rasile, Marco; Mantovani, Cristina; Pozzi, Davide; Garlanda, Cecilia; Mantovani, Alberto; Menna, Elisabetta; Barco, Angel; Matteoli, Michela
Inflammation modifies risk and/or severity of a variety of brain diseases through still elusive molecular mechanisms. Here we show that hyperactivation of the interleukin 1 pathway, through either ablation of the interleukin 1 receptor 8 (IL-1R8, also known as SIGIRR or Tir8) or activation of IL-1R, leads to up-regulation of the mTOR pathway and increased levels of the epigenetic regulator MeCP2, bringing to disruption of dendritic spine morphology, synaptic plasticity and plasticity-related gene expression. Genetic correction of MeCP2 levels in IL-1R8 KO neurons rescues the synaptic defects. Pharmacological inhibition of IL-1R activation by Anakinra corrects transcriptional changes, restores MeCP2 levels and spine plasticity and ameliorates cognitive defects in IL-1R8 KO mice. By linking for the first time neuronal MeCP2, a key player in brain development, to immune activation and demonstrating that synaptic defects can be pharmacologically reversed, these data open the possibility for novel treatments of neurological diseases through the immune system modulation.
Rossios, Christos; Pavlidis, Stelios; Hoda, Uruj; Kuo, Chih-Hsi; Wiegman, Coen; Russell, Kirsty; Sun, Kai; Loza, Matthew J; Baribaud, Frederic; Durham, Andrew L; Ojo, Oluwaseun; Lutter, Rene; Rowe, Anthony; Bansal, Aruna; Auffray, Charles; Sousa, Ana; Corfield, Julie; Djukanovic, Ratko; Guo, Yike; Sterk, Peter J; Chung, Kian Fan; Adcock, Ian M
Sputum analysis in asthmatic patients is used to define airway inflammatory processes and might guide therapy. We sought to determine differential gene and protein expression in sputum samples from patients with severe asthma (SA) compared with nonsmoking patients with mild/moderate asthma. Induced sputum was obtained from nonsmoking patients with SA, smokers/ex-smokers with severe asthma, nonsmoking patients with mild/moderate asthma (MMAs), and healthy nonsmoking control subjects. Differential cell counts, microarray analysis of cell pellets, and SOMAscan analysis of sputum analytes were performed. CRID3 was used to inhibit the inflammasome in a mouse model of SA. Eosinophilic and mixed neutrophilic/eosinophilic inflammation were more prevalent in patients with SA compared with MMAs. Forty-two genes probes were upregulated (>2-fold) in nonsmoking patients with severe asthma compared with MMAs, including IL-1 receptor (IL-1R) family and nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain containing 3 (NRLP3) inflammasome members (false discovery rate < 0.05). The inflammasome proteins nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 1 (NLRP1), NLRP3, and nucleotide-binding oligomerization domain (NOD)-like receptor C4 (NLRC4) were associated with neutrophilic asthma and with sputum IL-1β protein levels, whereas eosinophilic asthma was associated with an IL-13-induced TH2 signature and IL-1 receptor-like 1 (IL1RL1) mRNA expression. These differences were sputum specific because no activation of NLRP3 or enrichment of IL-1R family genes in bronchial brushings or biopsy specimens in patients with SA was observed. Expression of NLRP3 and of the IL-1R family genes was validated in the Airway Disease Endotyping for Personalized Therapeutics cohort. Inflammasome inhibition using CRID3 prevented airway hyperresponsiveness and airway inflammation (both neutrophilia and eosinophilia) in a mouse model
Ferrao, Ryan; Li, Jixi; Bergamin, Elisa; Wu, Hao
The Toll-like receptor (TLR)/IL-1 receptor (IL-1R) superfamily plays fundamentally important roles in innate immune and inflammatory responses. Recent structural studies have begun to unveil the surprising concept that upon ligand stimulation TLR/IL-1Rs assemble large oligomeric intracellular signaling complexes, or signalosomes, to induce activation of ubiquitin ligases and kinases, leading eventually to activation of the transcription factors that are responsible for the expression of immune and inflammatory response genes. The different scaffolds of assembly identified from the structural studies provide a molecular foundation in understanding the formation of microscopically visible signaling clusters that have long been known to cell biologists. Here, we illustrate the potential mechanisms of assembly step by step from the membrane proximal interactions to the more downstream events. Formation of large oligomeric signalosomes may help to establish a digital, threshold response in TLR/IL-1R signaling. PMID:22649099
Bulek, Katarzyna; Swaidani, Shadi; Qin, Jinzhong; Lu, Yi; Gulen, Muhammet F; Herjan, Tomasz; Min, Booki; Kastelein, Robert A; Aronica, Mark; Kosz-Vnenchak, Magdalena; Li, Xiaoxia
A novel cytokine IL-33, an IL-1 family member, signals via ST2 receptor and promotes Th2 responses, through the activation of NF-kappaB and MAP kinases. Previous studies reported that single Ig IL-1R-related molecule (SIGIRR)/Toll IL-1R8 acts as negative regulator for TLR-IL-1R-mediated signaling. We now found that SIGIRR formed a complex with ST2 upon IL-33 stimulation and specifically inhibited IL-33/ST2-mediated signaling in cell culture model. Furthermore, IL-33-induced Th2 response was enhanced in SIGIRR-deficient mice compared with that in wild-type control mice, suggesting a negative regulatory role of SIGIRR in IL-33/ST2 signaling in vivo. Similar to ST2, SIGIRR was highly expressed in in vitro polarized Th2 cells, but not Th1 cells. SIGIRR-deficient Th2 cells produce higher levels of Th2 cytokines, including IL-5, IL-4, and IL-13, than that in wild-type cells. Moreover, SIGIRR-deficient mice developed stronger Th2 immune response in OVA-challenged asthma model. Taken together, our results suggest that SIGIRR plays an important role in the regulation of Th2 response in vivo, possibly through its impact on IL-33-ST2-mediated signaling.
Wang, Pamella H. M.; Campanholle, Gabriela; Cenedeze, Marcos A.; Feitoza, Carla Q.; Gonçalves, Giselle M.; Landgraf, Richardt G.; Jancar, Sonia; Pesquero, João B.; Pacheco-Silva, Alvaro; Câmara, Niels O. S.
Previously we have demonstrated that bradykinin B1 receptor deficient mice (B1KO) were protected against renal ischemia and reperfusion injury (IRI). Here, we aimed to analyze the effect of B1 antagonism on renal IRI and to study whether B1R knockout or antagonism could modulate the renal expression of pro and anti-inflammatory molecules. To this end, mice were subjected to 45 minutes ischemia and reperfused at 4, 24, 48 and 120 hours. Wild-type mice were treated intra-peritoneally with antagonists of either B1 (R-954, 200 µg/kg) or B2 receptor (HOE140, 200 µg/kg) 30 minutes prior to ischemia. Blood samples were collected to ascertain serum creatinine level, and kidneys were harvested for gene transcript analyses by real-time PCR. Herein, B1R antagonism (R-954) was able to decrease serum creatinine levels, whereas B2R antagonism had no effect. The protection seen under B1R deletion or antagonism was associated with an increased expression of GATA-3, IL-4 and IL-10 and a decreased T-bet and IL-1β transcription. Moreover, treatment with R-954 resulted in lower MCP-1, and higher HO-1 expression. Our results demonstrated that bradykinin B1R antagonism is beneficial in renal IRI. PMID:18725957
O'Connell, Susan M; O'Regan, Grainne M; Bolger, Turlough; Hoffman, Hal M; Cant, Andrew; Irvine, Alan D; Watson, Rosemarie M
Familial cold auto-inflammatory syndrome, Muckle-Wells syndrome and chronic infantile neurologic, cutaneous, articular syndrome are related disorders associated with mutations in the CIAS1 gene. They appear to represent a continuum of one disease characterized by IL-1-mediated inflammation. Until recently, these conditions have been difficult to treat; however, with the advent of IL-1-receptor antagonist therapy, many reports of successful treatment of patients with these autoinflammatory diseases have emerged in the past 2 years. We describe an 8-year-old girl, diagnosed with Familial cold auto-inflammatory syndrome, confirmed by presence of a novel CIAS1 mutation, who was refractory to symptomatic treatment. As frequent attacks of urticaria and associated arthralgia had a debilitating effect on the child's lifestyle, a trial of IL-1-receptor antagonist (anakinra) was instituted. Dramatic sustained clinical improvement was evident within days and serum amyloid and C-reactive protein levels normalized within a month. Although several authors have reported successful use of this agent in children with chronic infantile neurologic, cutaneous, articular syndrome, we believe ours is the first report of successful treatment with anakinra in a young child with familial cold auto-inflammatory syndrome.
Pasi, Shweta; Kant, Ravi; Gupta, Sarika; Surolia, Avadhesha
Protein therapeutics targeting inflammatory mediators have shown great promise for the treatment of autoimmunities such as rheumatoid arthritis (RA). However, a significant challenge in this area has been their low in vivo stability and consequently their severely compromised therapeutic efficacy. One such therapeutic molecule IL-1 receptor antagonist (IL-1ra), used in the treatment of rheumatoid arthritis, has displayed only modest efficacy in human clinical trials owing to its short biological half-life. Herein, we report a novel approach to conglomerate individual protein entities into a drug depot by incorporation of an amyloidogenic motif Lys-Phe-Phe-Glu (KFFE) thereby dramatically improving their systemic persistence and in turn their therapeutic efficacy in a mice model of autoimmune arthritis. Copyright © 2014 Elsevier Ltd. All rights reserved.
Martin, Praxedis; Palmer, Gaby; Vigne, Solenne; Lamacchia, Céline; Rodriguez, Emiliana; Talabot-Ayer, Dominique; Rose-John, Stefan; Chalaris, Athena; Gabay, Cem
The proinflammatory activities of IL-1 are tightly controlled at different levels. IL-1R2 acts as a decoy receptor and has been shown to regulate the biological effects of IL-1 in vitro and in vivo. However, little is known about its natural expression in the mouse in physiologic and pathologic conditions. In this study, we examined IL-1R2 mRNA and protein expression in isolated cells and tissues in response to different stimulatory conditions. Data obtained using ex vivo CD11b(+)Ly6G(+) peripheral blood cells and in vitro-differentiated CD11b(+)Ly6G(+) BMG indicated that neutrophils are the major source of constitutively expressed IL-1R2 in the mouse. The expression of IL-1R2 on BMG and ex vivo Ly6G(+) peripheral blood cells was highly up-regulated by HC. IL-1R2 pull-down experiments showed that mouse rIL-1β binds to BMG IL-1R2, whereas binding of IL-1Ra could not be detected. Furthermore, LPS treatment induced shedding of IL-1R2 from the neutrophil membrane in vitro and in vivo, executed mainly by ADAM17. Finally, in in vivo models of inflammation, including thioglycolate-induced acute peritonitis and acute lung injury, infiltrating Ly6G(+) neutrophils, expressed IL-1R2. Our data show that in the mouse, neutrophils mainly express the decoy receptor IL-1R2 under naïve and inflammatory conditions. These data suggest that neutrophils may contribute to the resolution of acute inflammation.
Barry, Jessica; Loh, Zhixuan; Collison, Adam; Mazzone, Stuart; Lalwani, Amit; Zhang, Vivian; Davidson, Sophia; Wybacz, Elisha; Garlanda, Cecilia; Mantovani, Alberto; Mattes, Joerg; Foster, Paul S; Phipps, Simon
Allergic asthma is a chronic inflammatory disease predominately associated with the activation of CD4(+) T helper Type 2 (Th2) cells. Innate pattern recognition receptors are widely acknowledged to shape the adaptive immune response. For example, the activation of airway epithelial Toll-like receptor-4 (TLR4) is necessary for the generation of house dust mite (HDM)-specific Th2 responses and the development of asthma in mice. Here we sought to determine whether the absence of Toll-interleukin-1 receptor (TIR)-8, a negative regulator of TLR4 signaling that is highly expressed in airway epithelial cells, would exacerbate HDM-induced asthma in a murine model. We found that Th2 but not Th1 or Th17 cytokine expression was significantly reduced in the lung and draining lymph nodes in HDM-sensitized/challenged TIR8 gene-deleted mice. Mucus-producing goblet cells, HDM-specific IgG1, and airway hyperreactivity were also significantly reduced in HDM-exposed, TIR8-deficient mice. Consistent with the attenuated Th2 response, eotaxin-2/CCL24 expression and airway and peribronchial eosinophils were significantly reduced in the absence of TIR8. In contrast, IL-17A-responsive chemokines and neutrophil numbers were unaffected. Similar findings were obtained for cockroach allergen. HDM sensitization alone up-regulated the expression of IL-1F5, a putative TIR8 ligand and inducer of IL-4. Of note, innate IL-4, IL-5, IL-13, and IL-33 cytokine expression was reduced during HDM sensitization in the absence of TIR8, as was the recruitment of conventional dendritic cells and basophils to the draining lymph nodes. Our findings suggest that TIR8 enhances the development of HDM-induced innate and adaptive Th2, but not Th1 or Th17 type immunity.
Identification of TIFA as an adapter protein that links tumor necrosis factor receptor-associated factor 6 (TRAF6) to interleukin-1 (IL-1) receptor-associated kinase-1 (IRAK-1) in IL-1 receptor signaling.
Takatsuna, Hiroshi; Kato, Hiroki; Gohda, Jin; Akiyama, Taishin; Moriya, Ayaka; Okamoto, Yoshinari; Yamagata, Yuriko; Otsuka, Masami; Umezawa, Kazuo; Semba, Kentaro; Inoue, Jun-Ichiro
Tumor necrosis factor receptor-associated factor 6 (TRAF6) transduces signals from members of the Toll/interleukin-1 (IL-1) receptor family by interacting with IL-1 receptor-associated kinase-1 (IRAK-1) after IRAK-1 is released from the receptor-MyD88 complex upon IL-1 stimulation. However, the molecular mechanisms underlying regulation of the IRAK-1/TRAF6 interaction are largely unknown. We have identified TIFA, a TRAF-interacting protein with a forkhead-associated (FHA) domain. The FHA domain is a motif known to bind directly to phosphothreonine and phosphoserine. In transient transfection assays, TIFA activates NFkappaBeta and c-Jun amino-terminal kinase. However, TIFA carrying a mutation that abolishes TRAF6 binding or mutations in the FHA domain that are known to abolish FHA domain binding to phosphopeptide fails to activate NFkappaBeta and c-Jun amino-terminal kinase. TIFA, when overexpressed, binds both TRAF6 and IRAK-1 and significantly enhances the IRAK-1/TRAF6 interaction. Furthermore, analysis of endogenous proteins indicates that TIFA associates with TRAF6 constitutively, whereas it associates with IRAK-1 in an IL-1 stimulation-dependent manner in vivo. Thus, TIFA is likely to mediate IRAK-1/TRAF6 interaction upon IL-1 stimulation.
Devlin, Cecilia M; Kuriakose, George; Hirsch, Emmet; Tabas, Ira
Inflammatory cytokines have been linked to atherosclerosis by using cell culture models and acute inflammation in animals. The goal of this study was to examine lipoprotein levels and early atherosclerosis in chronic animal models of altered IL-1 physiology by using mice with deficient or excess IL-1 receptor antagonist (IL-1ra). IL-1ra knockout C57BL/6J mice fed a cholesterol/cholate diet for 3 mo had a 3-fold decrease in non-high-density lipoprotein cholesterol and a trend toward increased foam-cell lesion area compared to wild-type littermate controls. IL-1ra transgenic/low-density lipoprotein receptor (LDLR) knockout mice fed a cholesterol-saturated fat diet for 10 wk showed a 40% increase in non-high-density lipoprotein cholesterol, consistent with the IL-1ra knockout data, although there was no change in lesion size. When these IL1-ra overexpressing transgenic mice on the LDLR knockout background were fed a high-cholesterol/high-fat diet containing cholate, however, a statistically significant 40% decrease in lesion area was observed compared to LDLR knockout mice lacking the transgene. By immunohistochemistry, IL-1ra was present in C57BL/6J and LDLR knockout aortae, absent in IL-1ra knockout aortae, and present at high levels in LDLR knockout/IL-1ra transgene aortae. In summary, IL-1ra tended to increase plasma lipoprotein levels and, when fed a cholate-containing diet, decrease foam-cell lesion size. These data demonstrate that in selected models of murine atherosclerosis, chronic IL-1ra depletion or overexpression has potentially important effects on lipoprotein metabolism and foam-cell lesion development.
Born, T L; Smith, D E; Garka, K E; Renshaw, B R; Bertles, J S; Sims, J E
Two novel members of the interleukin-1 receptor (IL-1R) family, identified by homology searches of human genomic sequence data bases, are described. The genes have been named according to their structural features: TIGIRR-1 (three immunoglobulin domain-containing IL-1 receptor-related) and TIGIRR-2. TIGIRR-2 has recently been identified as causing mental retardation when mutated (Carrie, A., Jun, L., Bienvenu, T., Vinet, M. C., McDonell, N., Couvert, P., Zemni, R., Cardona, A., Van Buggenhout, G., Frints, S., Hamel, B., Moraine, C., Ropers, H. H., Strom, T., Howell, G. R., Whittaker, A., Ross, M. T., Kahn, A., Fryns, J. P., Beldjord, C., Marynen, P., and Chelly, J. (1999) Nat. Genet. 23, 25-31) and called IL1RAPL, a name we will also use henceforth. Neither receptor alone was able to mediate transcriptional activation of NF-kappaB in response to IL-1alpha, IL-1beta, or IL-18. In order to begin to elucidate the function of these and other orphan IL-1R family members, we have developed a functional assay utilizing a panel of chimeric receptors containing the extracellular and transmembrane domains of either type I IL-1R or IL-1R accessory protein (AcP) coupled to the cytoplasmic domains of all family members. Coexpression of each IL-1R chimera with each AcP chimera and an NF-kappaB-responsive reporter demonstrated that the cytoplasmic domains could be classified as IL-1R-like, AcP-like, or neither. Any IL-1R-like cytoplasmic domain could cooperate with any AcP-like cytoplasmic domain. The TIGIRR-1 and IL1RAPL cytoplasmic domains, however, were unable to signal as either IL-1R-like or AcP-like components, suggesting that they function as a new class of receptors within this family.
Knudsen, Louise; Hansen, Bo Falck; Jensen, Pia; Pedersen, Thomas Åskov; Vestergaard, Kirsten; Schäffer, Lauge; Blagoev, Blagoy; Oleksiewicz, Martin B.; Kiselyov, Vladislav V.; De Meyts, Pierre
Insulin can trigger metabolic as well as mitogenic effects, the latter being pharmaceutically undesirable. An understanding of the structure/function relationships between insulin receptor (IR) binding and mitogenic/metabolic signalling would greatly facilitate the preclinical development of new insulin analogues. The occurrence of ligand agonism and antagonism is well described for G protein-coupled receptors (GPCRs) and other receptors but in general, with the exception of antibodies, not for receptor tyrosine kinases (RTKs). In the case of the IR, no natural ligand or insulin analogue has been shown to exhibit antagonistic properties, with the exception of a crosslinked insulin dimer (B29-B’29). However, synthetic monomeric or dimeric peptides targeting sites 1 or 2 of the IR were shown to be either agonists or antagonists. We found here that the S961 peptide, previously described to be an IR antagonist, exhibited partial agonistic effects in the 1–10 nM range, showing altogether a bell-shaped dose-response curve. Intriguingly, the agonistic effects of S961 were seen only on mitogenic endpoints (3H-thymidine incorporation), and not on metabolic endpoints (14C-glucose incorporation in adipocytes and muscle cells). The agonistic effects of S961 were observed in 3 independent cell lines, with complete concordance between mitogenicity (3H-thymidine incorporation) and phosphorylation of the IR and Akt. Together with the B29-B’29 crosslinked dimer, S961 is a rare example of a mixed agonist/antagonist for the human IR. A plausible mechanistic explanation based on the bivalent crosslinking model of IR activation is proposed. PMID:23300584
Wang, Xinyan; Yang, Xiao; Wen, Chao; Gao, Yajun; Qin, Lei; Zhang, Shengnan; Zhang, Anying; Yang, Kun; Zhou, Hong
In the present study, effects of TGF-β1 on IL-1β signaling during inflammatory response were examined in grass carp. In grass carp head kidney leukocytes (HKLs), LPS significantly induced the mRNA expression of grass carp TGF-β1 (gcTGF-β1) and IL-1β, indicating the involvement of TGF-β1 and IL-1β in inflammatory process. Using anti-IL-1β antibody to neutralize the endogenous IL-1β, we found that stimulation of IL-1β mRNA expression by LPS was independent on IL-1β itself. Interestingly, recombinant gcTGF-β1 (rgcTGF-β1) suppressed basal and LPS-stimulated IL-1β mRNA expression in spite of immunoneutralizing endogenous IL-1β or not. Given that IL-1β receptor signaling molecule and natural IL-1β inhibitors are the important regulators in IL-1β signaling and activity, the effect of LPS on these molecules' expression was determined in HKLs. Results showed that LPS significantly enhanced the mRNA levels of IL-1 receptor type I (IL-1RI) and II (IL-1RII), IL-1R accessory protein (IL-1Racp) and novel IL-1 family member (nIL-1F). Moreover, the induction of IL-1RII, IL-1Racp and nIL-1F by LPS was IL-1β-dependent since IL-1β immunoneutralization abolished these inductions, implying the involvement of IL-1β auto-induction in these effects. Consistently, TGF-β1 could block basal IL-1RI and nIL-1F mRNA expression, and LPS-induced IL-1RI, IL-1Racp and nIL-1F mRNA expression, suggesting these molecules as the regulatory sites for TGF-β1 to modulate IL-1β signaling. Subsequent in vivo studies showed that bacterial challenge significantly up-regulated IL-1β mRNA expression with a rapid and transient pattern and TGF-β1 mRNA expression with a relatively time-delayed kinetics in head kidney. These expression patterns coincide with their pro-inflammatory and anti-inflammatory roles, respectively. As expected, rgcTGF-β1 could suppress bacterial-induced IL-1β mRNA expression, strengthening the anti-inflammatory role of TGF-β1 in vivo. Taken together, these
Butter, Loes M.; Teske, Gwendoline J. D.; Stroo, Ingrid; Pulskens, Wilco P.; Florquin, Sandrine
Our immune system has to constantly strike a balance between activation and inhibition of an inflammatory response to combat invading pathogens and avoid inflammation-induced collateral tissue damage. Toll interleukin-1 receptor 8 (IL-1R-8)/single Ig domain IL-1R-related molecule (TIR8/SIGIRR) is an inhibitor of Toll-like receptor (TLR)/IL-1R signaling, which is predominantly expressed in the kidney. The biological role of renal TIR8 during infection is, however, unknown. We therefore evaluated renal TIR8 expression during Escherichia coli pyelonephritis and explored its role in host defense using TIR8−/− versus TIR8+/+ mice. We found that TIR8 protein is abundantly present in the majority of cortical tubular epithelial cells. Pyelonephritis resulted in a significant downregulation of TIR8 mRNA in kidneys of TIR8+/+ mice. TIR8 inhibited an effective host response against E. coli, as indicated by diminished renal bacterial outgrowth and dysfunction in TIR8−/− mice. This correlated with increased amounts of circulating and intrarenal neutrophils at the early phase of infection. TIR8−/− tubular epithelial cells had increased cytokine/chemokine production when stimulated with lipopolysaccharide (LPS) or heat-killed E. coli, suggesting that TIR8 played an anti-inflammatory role during pathogen stimulation by inhibiting LPS signaling. These data suggest that TIR8 is an important negative regulator of an LPS-mediated inflammatory response in tubular epithelial cells and dampens an effective antibacterial host response during pyelonephritis caused by uropathogenic E. coli. PMID:22890991
Leemans, Jaklien C; Butter, Loes M; Teske, Gwendoline J D; Stroo, Ingrid; Pulskens, Wilco P; Florquin, Sandrine
Our immune system has to constantly strike a balance between activation and inhibition of an inflammatory response to combat invading pathogens and avoid inflammation-induced collateral tissue damage. Toll interleukin-1 receptor 8 (IL-1R-8)/single Ig domain IL-1R-related molecule (TIR8/SIGIRR) is an inhibitor of Toll-like receptor (TLR)/IL-1R signaling, which is predominantly expressed in the kidney. The biological role of renal TIR8 during infection is, however, unknown. We therefore evaluated renal TIR8 expression during Escherichia coli pyelonephritis and explored its role in host defense using TIR8(-/-) versus TIR8(+/+) mice. We found that TIR8 protein is abundantly present in the majority of cortical tubular epithelial cells. Pyelonephritis resulted in a significant downregulation of TIR8 mRNA in kidneys of TIR8(+/+) mice. TIR8 inhibited an effective host response against E. coli, as indicated by diminished renal bacterial outgrowth and dysfunction in TIR8(-/-) mice. This correlated with increased amounts of circulating and intrarenal neutrophils at the early phase of infection. TIR8(-/-) tubular epithelial cells had increased cytokine/chemokine production when stimulated with lipopolysaccharide (LPS) or heat-killed E. coli, suggesting that TIR8 played an anti-inflammatory role during pathogen stimulation by inhibiting LPS signaling. These data suggest that TIR8 is an important negative regulator of an LPS-mediated inflammatory response in tubular epithelial cells and dampens an effective antibacterial host response during pyelonephritis caused by uropathogenic E. coli.
Machado-Carvalho, Liliana; Martín, Margarita; Torres, Rosa; Gabasa, Marta; Alobid, Isam; Mullol, Joaquim; Pujols, Laura; Roca-Ferrer, Jordi; Picado, Cesar
We hypothesized that the 2 reported alterations in aspirin-exacerbated respiratory disease (AERD), reduced expression/production of COX-2/prostaglandin (PG) E2 and diminished expression of E-prostanoid (EP) 2 receptor, are closely linked. We sought to determine the mechanisms involved in the altered regulation of the COX pathway in patients with AERD. Fibroblasts were obtained from nasal mucosa; samples of control subjects (NM-C, n = 8) and from nasal polyps from patients with aspirin-exacerbated respiratory disease (NP-AERD, n = 8). Expression of the autocrine loop components regulating PGE2 production and signaling, namely IL-1 type I receptor (IL-1RI), COX-2, microsomal prostaglandin E synthase 1 (mPGES-1), and EP receptors, was assessed at baseline and after stimulation with IL-1β, PGE2, and specific EP receptor agonists. Compared with NM-C fibroblasts, basal expression levels of IL-1RI and EP2 receptor were lower in NP-AERD fibroblasts. IL-1β-induced IL-1RI, COX-2, and mPGES-1 expression levels were also lower in these cells. Levels of IL-1RI positively correlated with COX-2 and mPGES-1 expression in both NM-C and NP-AERD fibroblasts. Incubation with either exogenous PGE2 or selective EP2 agonist significantly increased expression of IL-1RI in NM-C fibroblasts and had hardly any effect on NP-AERD fibroblasts. Alterations in IL-1RI, COX-2, and mPGES-1 expression that were found in NP-AERD fibroblasts were corrected when EP2 receptor expression was normalized by transfection of NP-AERD fibroblasts. Altered expression of EP2 in patients with AERD contributes to deficient induction of IL-1RI, reducing the capacity of IL-1β to increase COX-2 and mPGES-1 expression, which results in low PGE2 production. This impairment in the generation of PGE2 subsequently reduces its ability to induce IL-1RI. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Jensen, L E; Muzio, M; Mantovani, A; Whitehead, A S
The proinflammatory cytokine IL-1 induces the biosynthesis of a number of immunologically important proteins during infection, tissue damage, and/or stress, in part through the activation of the transcription factor NF-kappaB. Signal transduction is initiated at the cell membrane by complex formation between extracellular IL-1 and the transmembrane IL-1R type I (IL-1RI) and IL-1R accessory protein (IL-1RAcP). The intracellular signaling cascade involves recruitment of two IL-1R-associated kinases, IRAK1 and IRAK2, and the adapter protein MyD88, events which are dependent on the intracellular domain of membrane-bound IL-1RAcP (mIL-1RAcP). In mouse liver, IL-1RAcP is expressed as a soluble protein (sIL-1RAcP), the function of which is unknown. We have cloned the human sIL-1RAcP and established by sequence analysis that the human sIL-1RAcP mRNA arises from alternative splicing of the IL-1RAcP gene (shown here to encompass 12 exons spanning more than 56 kb). Furthermore, we demonstrate that human HepG2 hepatoma cells express both mIL-1RAcP and sIL-1RAcP and that signal transduction in these cells is mediated through IRAK1, IRAK2, and MyD88. We show that phorbol esters induce a change in the pre-mRNA splice pattern such that sIL-1RAcP mRNA becomes the dominant form. Overexpression of a membrane-anchored fusion protein of sIL-1RAcP and MHC in HepG2 cells inhibits IL-1-mediated NF-kappaB activation, whereas coexpression of IL-1RI with membrane-anchored sIL-1RAcP restores the capacity of the cells to respond to IL-1. This suggests that sIL-1RAcP may act as an inhibitor of IL-1 by directly interacting with IL-1RI to abolish its capacity to transduce signal.
Véliz Rodriguez, Tania; Moalli, Federica; Polentarutti, Nadia; Paroni, Moira; Bonavita, Eduardo; Anselmo, Achille; Nebuloni, Manuela; Mantero, Stefano; Jaillon, Sébastien; Bragonzi, Alessandra; Mantovani, Alberto; Riva, Federica
Toll interleukin-1 receptor (IL-1R) 8 (TIR8), also known as single Ig IL-1 receptor (IL-R)-related molecule, or SIGIRR, is a member of the IL-1R-like family, primarily expressed by epithelial cells. Current evidence suggests that TIR8 plays a nonredundant role as a negative regulator in vivo under different inflammatory conditions that are dependent on IL-R and Toll-like receptor (TLR) activation. In the present study, we examined the role of TIR8 in innate resistance to acute lung infections caused by Pseudomonas aeruginosa, a Gram-negative pathogen responsible for life-threatening infections in immunocompromised individuals and cystic fibrosis patients. We show that Tir8 deficiency in mice was associated with increased susceptibility to acute P. aeruginosa infection, in terms of mortality and bacterial load, and to exacerbated local and systemic production of proinflammatory cytokines (gamma interferon [IFN-γ], tumor necrosis factor alpha [TNF-α], IL-1β, and IL-6) and chemokines (CXCL1, CXCL2, and CCL2). It has been reported that host defense against P. aeruginosa acute lung infection can be improved by blocking IL-1 since exaggerated IL-1β production may be harmful for the host in this infection. In agreement with these data, IL-1RI deficiency rescues the phenotype observed in Tir8-deficient mice: in Tir8−/− IL-1RI−/− double knockout mice we observed higher survival rates, enhanced bacterial clearance, and reduced levels of local and systemic cytokine and chemokine levels than in Tir8-deficient mice. These results suggest that TIR8 has a nonredundant effect in modulating the inflammation caused by P. aeruginosa, in particular, by negatively regulating IL-1RI signaling, which plays a major role in the pathogenesis of this infectious disease. PMID:22025515
Rogier, Rebecca; Ederveen, Thomas H A; Boekhorst, Jos; Wopereis, Harm; Scher, Jose U; Manasson, Julia; Frambach, Sanne J C M; Knol, Jan; Garssen, Johan; van der Kraan, Peter M; Koenders, Marije I; van den Berg, Wim B; van Hijum, Sacha A F T; Abdollahi-Roodsaz, Shahla
Perturbation of commensal intestinal microbiota has been associated with several autoimmune diseases. Mice deficient in interleukin-1 receptor antagonist (Il1rn (-/-) mice) spontaneously develop autoimmune arthritis and are susceptible to other autoimmune diseases such as psoriasis, diabetes, and encephalomyelitis; however, the mechanisms of increased susceptibility to these autoimmune phenotypes are poorly understood. We investigated the role of interleukin-1 receptor antagonist (IL-1Ra) in regulation of commensal intestinal microbiota, and assessed the involvement of microbiota subsets and innate and adaptive mucosal immune responses that underlie the development of spontaneous arthritis in Il1rn (-/-) mice. Using high-throughput 16S rRNA gene sequencing, we show that IL-1Ra critically maintains the diversity and regulates the composition of intestinal microbiota in mice. IL-1Ra deficiency reduced the intestinal microbial diversity and richness, and caused specific taxonomic alterations characterized by overrepresented Helicobacter and underrepresented Ruminococcus and Prevotella. Notably, the aberrant intestinal microbiota in IL1rn (-/-) mice specifically potentiated IL-17 production by intestinal lamina propria (LP) lymphocytes and skewed the LP T cell balance in favor of T helper 17 (Th17) cells, an effect transferable to WT mice by fecal microbiota. Importantly, LP Th17 cell expansion and the development of spontaneous autoimmune arthritis in IL1rn (-/-) mice were attenuated under germ-free condition. Selective antibiotic treatment revealed that tobramycin-induced alterations of commensal intestinal microbiota, i.e., reduced Helicobacter, Flexispira, Clostridium, and Dehalobacterium, suppressed arthritis in IL1rn (-/-) mice. The arthritis phenotype in IL1rn (-/-) mice was previously shown to depend on Toll-like receptor 4 (TLR4). Using the ablation of both IL-1Ra and TLR4, we here show that the aberrations in the IL1rn (-/-) microbiota are partly TLR4
Chen, Xuxin; Wu, Xueling; Zhao, Yunfeng; Wang, Guansong; Feng, Jian; Li, Qi; Qian, Guisheng
Previous studies have shown that single immunoglobulin IL-1 receptor-related molecule (SIGIRR) is a negative regulator of Toll-Interleukin-1 receptor signaling. Nevertheless, the molecular mechanism of the negatively regulatory effect of SIGIRR remains unknown. Using a yeast two-hybrid screen, we identified paralemmin-3 (PALM3) as a novel binding protein of SIGIRR. This interaction of SIGIRR with PALM3 was confirmed by coimmunoprecipitation in mammalian cells. In addition, the PALM3 mRNA expression was upregulated by lipopolysaccharide (LPS)-stimulation in a human alveolar epithelial cell line (A549 cells). Furthermore, silencing PALM3 by RNA interference inhibited the release of inflammatory cytokines in A549 cells after LPS-stimulation. These results suggest that PALM3 may function as an adaptor in the LPS- Toll-like receptor 4 signaling and the interaction of SIGIRR with PALM3 may partly account for the mechanism of the negatively regulatory effect of SIGIRR. Copyright © 2010 Elsevier Inc. All rights reserved.
Bahi, Nadia; Friocourt, Gaelle; Carrié, Alain; Graham, Margaret E; Weiss, Jamie L; Chafey, Philippe; Fauchereau, Fabien; Burgoyne, Robert D; Chelly, Jamel
Previously, human genetics-based approaches allowed us to show that mutations in the IL-1 receptor accessory protein-like gene (IL1RAPL) are responsible for a non-specific form of X-linked mental retardation. This gene encodes a predicted protein of 696 amino acids that belongs to a novel class of the IL-1/Toll receptor family. In addition to the extracellular portion consisting of three Ig-like domains and the intracellular TIR domain characteristic of the IL-1/Toll receptor family, IL1RAPL contains a specific 150 amino acid carboxy terminus that has no significant homology with any protein of known function. In order to begin to elucidate the function of this IL-1/Toll receptor-like protein, we have assessed the effect of recombinant IL1RAPL on the binding affinity of type I IL-1R for its ligands IL-1alpha and beta and searched for proteins interacting with the specific carboxy terminus domain of IL1RAPL. Our results show that IL1RAPL is not a protein receptor for IL-1. In addition we present here the identification of Neuronal Calcium Sensor-1 (NCS-1) as an IL1RAPL interactor. Remarkably, although NCS-1 and its non-mammalian homologue, frequenin, are members of a highly conserved EF-hand Ca(2+) binding protein family, our data show that IL1RAPL interacts only with NCS-1 through its specific C-terminal domain. The functional relevance of IL1RAPL activity was further supported by the inhibitory effect on exocytosis in PC12 cells overexpressing IL1RAPL. Taken together, our data suggest that IL1RAPL may regulate calcium-dependent exocytosis and provide insight into the understanding of physiopathological mechanisms underlying cognitive impairment resulting from IL1RAPL dysfunction.
Barreyro, Laura; Will, Britta; Bartholdy, Boris; Zhou, Li; Todorova, Tihomira I.; Stanley, Robert F.; Ben-Neriah, Susana; Montagna, Cristina; Parekh, Samir; Pellagatti, Andrea; Boultwood, Jacqueline; Paietta, Elisabeth; Ketterling, Rhett P.; Cripe, Larry; Fernandez, Hugo F.; Greenberg, Peter L.; Tallman, Martin S.; Steidl, Christian; Mitsiades, Constantine S.; Verma, Amit
Cellular and interpatient heterogeneity and the involvement of different stem and progenitor compartments in leukemogenesis are challenges for the identification of common pathways contributing to the initiation and maintenance of acute myeloid leukemia (AML). Here we used a strategy of parallel transcriptional analysis of phenotypic long-term hematopoietic stem cells (HSCs), short-term HSCs, and granulocyte-monocyte progenitors from individuals with high-risk (−7/7q−) AML and compared them with the corresponding cell populations from healthy controls. This analysis revealed dysregulated expression of 11 genes, including IL-1 receptor accessory protein (IL1RAP), in all leukemic stem and progenitor cell compartments. IL1RAP protein was found to be overexpressed on the surface of HSCs of AML patients, and marked cells with the −7/7q− anomaly. IL1RAP was also overexpressed on HSCs of patients with normal karyotype AML and high-risk myelodysplastic syndrome, suggesting a pervasive role in different disease subtypes. High IL1RAP expression was independently associated with poor overall survival in 3 independent cohorts of AML patients (P = 2.2 × 10−7). Knockdown of IL1RAP decreased clonogenicity and increased cell death of AML cells. Our study identified genes dysregulated in stem and progenitor cells in −7/7q− AML, and suggests that IL1RAP may be a promising therapeutic and prognostic target in AML and high-risk myelodysplastic syndrome. PMID:22723552
Barreyro, Laura; Will, Britta; Bartholdy, Boris; Zhou, Li; Todorova, Tihomira I; Stanley, Robert F; Ben-Neriah, Susana; Montagna, Cristina; Parekh, Samir; Pellagatti, Andrea; Boultwood, Jacqueline; Paietta, Elisabeth; Ketterling, Rhett P; Cripe, Larry; Fernandez, Hugo F; Greenberg, Peter L; Tallman, Martin S; Steidl, Christian; Mitsiades, Constantine S; Verma, Amit; Steidl, Ulrich
Cellular and interpatient heterogeneity and the involvement of different stem and progenitor compartments in leukemogenesis are challenges for the identification of common pathways contributing to the initiation and maintenance of acute myeloid leukemia (AML). Here we used a strategy of parallel transcriptional analysis of phenotypic long-term hematopoietic stem cells (HSCs), short-term HSCs, and granulocyte-monocyte progenitors from individuals with high-risk (-7/7q-) AML and compared them with the corresponding cell populations from healthy controls. This analysis revealed dysregulated expression of 11 genes, including IL-1 receptor accessory protein (IL1RAP), in all leukemic stem and progenitor cell compartments. IL1RAP protein was found to be overexpressed on the surface of HSCs of AML patients, and marked cells with the -7/7q- anomaly. IL1RAP was also overexpressed on HSCs of patients with normal karyotype AML and high-risk myelodysplastic syndrome, suggesting a pervasive role in different disease subtypes. High IL1RAP expression was independently associated with poor overall survival in 3 independent cohorts of AML patients (P = 2.2 × 10(-7)). Knockdown of IL1RAP decreased clonogenicity and increased cell death of AML cells. Our study identified genes dysregulated in stem and progenitor cells in -7/7q- AML, and suggests that IL1RAP may be a promising therapeutic and prognostic target in AML and high-risk myelodysplastic syndrome.
Duan, Jinyou; Chung, Hachung; Troy, Erin; Kasper, Dennis L.
SUMMARY IL-17 cytokine production by the Th17 T-cell subset is regulated by intestinal commmensals. We show microbial colonization also regulates innate IL-17 production. A population of CD62L− γ/δ T cells, in particular a lineage expressing the IL-1 receptor 1 (IL-1R1), can be quickly activated by microbes to produce IL-17. Antibiotic-treatment and monocolonization of mice suggest specific commensals—but not metronidazole-sensitive anaerobes like Bacteroides species—are required for maintaining IL-1R1+ γ/δ T cells. Signaling through the guanine nucleotide exchange factor VAV1 but not through Toll-like receptors or antigen presentation pathways is essential for inducing IL-1R1+ γ/δ T cells. Furthermore, IL-1R1+ γ/δ T cells are a potential source of IL-17 that can be activated by IL-23 and IL-1 in both infectious and noninfectious settings in vitro and in vivo. Thus, commensals orchestrate the expansion of phenotypically distinct γδ T cells and innate immunity is a three-way interaction between host, pathogens and microbiota. PMID:20159619
Chen, Chun-Jen; Shi, Yan; Hearn, Arron; Fitzgerald, Kate; Golenbock, Douglas; Reed, George; Akira, Shizuo; Rock, Kenneth L.
While it is known that monosodium urate (MSU) crystals cause the disease gout, the mechanism by which these crystals stimulate this inflammatory condition has not been clear. Here we find that the Toll/IL-1R (TIR) signal transduction adaptor myeloid differentiation primary response protein 88 (MyD88) is required for acute gouty inflammation. In contrast, other TIR adaptor molecules, TIRAP/Mal, TRIF, and TRAM, are not required for this process. The MyD88-dependent TLR1, -2, -4, -6, -7, -9, and -11 and IL-18 receptor (IL-18R) are not essential for MSU-induced inflammation. Moreover, MSU does not stimulate HEK cells expressing TLR1–11 to activate NF-κB. In contrast, mice deficient in the MyD88-dependent IL-1R showed reduced inflammatory responses, similar to those observed in MyD88-deficient mice. Similarly, mice treated with IL-1 neutralizing antibodies also showed reduced MSU-induced inflammation, demonstrating that IL-1 production and IL-1R activation play essential roles in MSU-triggered inflammation. IL-1R deficiency in bone marrow–derived cells did not affect the inflammatory response; however, it was required in non–bone marrow–derived cells. These results indicate that IL-1 is essential for the MSU-induced inflammatory response and that the requirement of MyD88 in this process is primarily through its function as an adaptor molecule in the IL-1R signaling pathway. PMID:16886064
Järås, Marcus; Johnels, Petra; Hansen, Nils; Ågerstam, Helena; Tsapogas, Panagiotis; Rissler, Marianne; Lassen, Carin; Olofsson, Tor; Bjerrum, Ole Weis; Richter, Johan; Fioretos, Thoas
Chronic myeloid leukemia (CML) is genetically characterized by the Philadelphia (Ph) chromosome, formed through a reciprocal translocation between chromosomes 9 and 22 and giving rise to the constitutively active tyrosine kinase P210 BCR/ABL1. Therapeutic strategies aiming for a cure of CML will require full eradication of Ph chromosome-positive (Ph+) CML stem cells. Here we used gene-expression profiling to identify IL-1 receptor accessory protein (IL1RAP) as up-regulated in CML CD34+ cells and also in cord blood CD34+ cells as a consequence of retroviral BCR/ABL1 expression. To test whether IL1RAP expression distinguishes normal (Ph−) and leukemic (Ph+) cells within the CML CD34+CD38− cell compartment, we established a unique protocol for conducting FISH on small numbers of sorted cells. By using this method, we sorted cells directly into drops on slides to investigate their Ph-chromosome status. Interestingly, we found that the CML CD34+CD38−IL1RAP+ cells were Ph+, whereas CML CD34+CD38−IL1RAP− cells were almost exclusively Ph−. By performing long-term culture-initiating cell assays on the two cell populations, we found that Ph+ and Ph− candidate CML stem cells could be prospectively separated. In addition, by generating an anti-IL1RAP antibody, we provide proof of concept that IL1RAP can be used as a target on CML CD34+CD38− cells to induce antibody-dependent cell-mediated cytotoxicity. This study thus identifies IL1RAP as a unique cell surface biomarker distinguishing Ph+ from Ph− candidate CML stem cells and opens up a previously unexplored avenue for therapy of CML. PMID:20805474
Järås, Marcus; Johnels, Petra; Hansen, Nils; Agerstam, Helena; Tsapogas, Panagiotis; Rissler, Marianne; Lassen, Carin; Olofsson, Tor; Bjerrum, Ole Weis; Richter, Johan; Fioretos, Thoas
Chronic myeloid leukemia (CML) is genetically characterized by the Philadelphia (Ph) chromosome, formed through a reciprocal translocation between chromosomes 9 and 22 and giving rise to the constitutively active tyrosine kinase P210 BCR/ABL1. Therapeutic strategies aiming for a cure of CML will require full eradication of Ph chromosome-positive (Ph(+)) CML stem cells. Here we used gene-expression profiling to identify IL-1 receptor accessory protein (IL1RAP) as up-regulated in CML CD34(+) cells and also in cord blood CD34(+) cells as a consequence of retroviral BCR/ABL1 expression. To test whether IL1RAP expression distinguishes normal (Ph(-)) and leukemic (Ph(+)) cells within the CML CD34(+)CD38(-) cell compartment, we established a unique protocol for conducting FISH on small numbers of sorted cells. By using this method, we sorted cells directly into drops on slides to investigate their Ph-chromosome status. Interestingly, we found that the CML CD34(+)CD38(-)IL1RAP(+) cells were Ph(+), whereas CML CD34(+)CD38(-)IL1RAP(-) cells were almost exclusively Ph(-). By performing long-term culture-initiating cell assays on the two cell populations, we found that Ph(+) and Ph(-) candidate CML stem cells could be prospectively separated. In addition, by generating an anti-IL1RAP antibody, we provide proof of concept that IL1RAP can be used as a target on CML CD34(+)CD38(-) cells to induce antibody-dependent cell-mediated cytotoxicity. This study thus identifies IL1RAP as a unique cell surface biomarker distinguishing Ph(+) from Ph(-) candidate CML stem cells and opens up a previously unexplored avenue for therapy of CML.
Jiménez-Garduño, Aura M; Mendoza-Rodríguez, Mónica G; Urrutia-Cabrera, Daniel; Domínguez-Robles, María C; Pérez-Yépez, Eloy A; Ayala-Sumuano, Jorge Tonatiuh; Meza, Isaura
Inflammation has been recently acknowledged as a key participant in the physiopathology of oncogenesis and tumor progression. The inflammatory cytokine IL-1β has been reported to induce the expression of markers associated with malignancy in breast cancerous cells through Epithelial-Mesenchymal Transition (EMT). Aggressive breast cancer tumors classified as Triple Negative do not respond to hormonal treatment because they lack three crucial receptors, one of which is the estrogen receptor alpha (ERα). Expression of ERα is then considered a good prognostic marker for tamoxifen treatment of this type of cancer, as the binding of this drug to the receptor blocks the transcriptional activity of the latter. Although it has been suggested that inflammatory cytokines in the tumor microenvironment could regulate ERα expression, the mechanism(s) involved in this process have not yet been established. We show here that, in a cell model of breast cancer cells (6D cells), in which the inflammatory cytokine IL-1β induces EMT by activation of the IL-1β/IL-1RI/β-catenin pathway, the up regulation of TWIST1 leads to methylation of the ESR1 gene promoter. This epigenetic modification produced significant decrease of the ERα receptor levels and increased resistance to tamoxifen. The direct participation of IL-1β in these processes was validated by blockage of the cytokine-induced signaling pathway by wortmannin inactivation of the effectors PI3K/AKT. These results support our previous reports that have suggested direct participation of the inflammatory cytokine IL-1β in the transition to malignancy of breast cancer cells. Copyright © 2017 Elsevier Inc. All rights reserved.
Klekotka, Paul A.; Yang, Liping; Yokoyama, Wayne M.
Contact hypersensitivity (CHS) requires activation of the innate immune system and results in an adaptive immune response. Many cells of the innate immune system use Toll-like receptors (TLRs), which signal through the adaptor protein MyD88, to initiate an immune response. MyD88 is also required for signaling downstream of the IL-1 and Il-18 receptors. Herein we studied the MyD88 signaling pathway in the CHS response to 2,4-dinitrofluorobenzene (DNFB). Mice deficient in MyD88 were unable to mount a CHS response to DNFB. In contrast, mice deficient in Toll/IL-1R-containing adaptor inducing IFN-β (TRIF), TLR2, TLR4, TLR6 and TLR9 had no defect in their ability to respond to DNFB. While both IL-1R and IL-18R-deficient mice showed a reduced CHS response to DNFB, in bone marrow chimera and adoptive transfer experiments, we found that MyD88 and the IL-18R were required in a radioresistant cell in the sensitization phase of the CHS response. In contrast, similar strategies revealed that the IL-1R was required in a radiosensitive cell in the sensitization phase of the CHS response. Taken together, these data indicate that the IL-1R and IL-18R/MyD88 pathways are required in distinctly different cells during the sensitization phase of CHS. PMID:19657352
Chiu, Gabriel S.; Darmody, Patrick T.; Walsh, John P.; Moon, Morgan L.; Kwakwa, Kristin A.; Bray, Julie K.; McCusker, Robert H.; Freund, Gregory G.
Anxiety is one of the most commonly reported psychiatric conditions, but its pathogenesis is poorly understood. Ailments associated with activation of the innate immune system, however, are increasingly linked to anxiety disorders. In adult male mice, we found that adenosine doubled caspase-1 activity in brain by a pathway reliant on ATP-sensitive potassium (KATP) channels, protein kinase A (PKA) and the A2A adenosine receptor (AR). In addition, adenosine-dependent activation of caspase-1 increased interleukin (IL)-1β in the brain by two-fold. Peripheral administration of adenosine in wild-type (WT) mice led to a 2.3-fold increase in caspase-1 activity in the amygdala and to a 33% and 42% reduction in spontaneous locomotor activity and food intake, respectively, that were not observed in caspase-1 knockout (KO), IL-1 receptor type 1 (IL-1R1) KO and A2A AR KO mice or in mice administered a caspase-1 inhibitor centrally. Finally, adenosine administration increased anxiety-like behaviors in WT mice by 28% in the open field test and by 55% in the elevated zero-maze. Caspase-1 KO mice, IL-1R1 KO mice, A2A AR KO mice and WT mice treated with the KATP channel blocker, glyburide, were resistant to adenosine-induced anxiety-like behaviors. Thus, our results indicate that adenosine can act as an anxiogenic by activating caspase-1 and increasing IL-1β in the brain. PMID:24907587
Inflammatory and hyperproliferative skin disease in mice that express elevated levels of the IL-1 receptor (type I) on epidermal keratinocytes. Evidence that IL-1-inducible secondary cytokines produced by keratinocytes in vivo can cause skin disease.
Groves, R W; Rauschmayr, T; Nakamura, K; Sarkar, S; Williams, I R; Kupper, T S
Interleukin (IL)-1 induces a cascade of secondary cytokines in a large number of cell types in vitro, including monocytes, fibroblasts, synovial cells, and keratinocytes. Although it has been proposed that autocrine or paracrine activation of such cells by IL- 1 in situ could orchestrate a local inflammatory response, formal proof for such an hypothesis has been lacking. In an attempt to lower the threshold for secondary cytokine production in these cells in response to IL-1, we have generated transgenic mice (designated IR10) which overexpress functional type 1 IL-1 receptor in basal layer of epidermis keratinocytes. As predicted, keratinocytes from these animals were substantially more responsive to exogenous IL-1 than nontransgenic keratinocytes when stimulated in vitro. When challenged with known inducers of keratinocyte IL-1 synthesis and release, skin of IR10 mice exhibited an exaggerated inflammatory response, characterized by epidermal hyperplasia and an acute dermal inflammatory cell infiltrate. In this setting, the secondary epidermal cytokines gro-alpha and GM-CSF were strongly induced in transgenic epidermis but not in control skin. To confirm that these changes were indeed related to IL-1 mediated activation pathways, IR10 mice were crossed to a distinct line of transgenic mice that overexpress 17-kD IL-l alpha in basal keratinocytes. Double transgenic mice derived from this cross breeding experiment developed spontaneous inflammation of the skin, similar in appearance to that induced by PMA, both histologically and macroscopically, and distinct from that seen in either parental strain spontaneously. Furthermore, secondary cytokines were more strongly induced in the double transgenic than in either parental strain. These findings conclusively demonstrate the potential for functional autocrine pathways of keratinocyte activation mediated by IL-1 alpha in vivo, and suggest that level of expression of type 1 IL-1 receptor may function as a significant
Crow, Andrew R; Song, Seng; Semple, John W; Freedman, John; Lazarus, Alan H
The exact mechanism of action of IVIg in the amelioration of immune thrombocytopenic purpura (ITP) is still unclear. Studies have suggested that IVIg may function through the regulation of cytokines, including interleukin-1 receptor antagonist (IL-1Ra), an inhibitor of phagocytosis. Using a mouse model relevant to ITP, we confirm an increase in mouse serum levels of IL-1Ra after exposure to IVIg, yet a recombinant IL-1Ra did not ameliorate thrombocytopenia. IVIg has also been shown to affect the expression of other regulatory cytokines. We have also recently established that IVIg specifically targets activating FcgammaRs on CD11c+ dendritic cells (DCs) as its primary mechanism of action in the amelioration of murine ITP. Herein, we show that IVIg functions therapeutically in mice lacking specific cytokines or their receptors that can potentially affect DC/macrophage function (IL-1 receptor, IL-4, IL-10, IL-12beta, TNF-alpha, IFN-gamma receptor, MIP-1alpha). This suggests that while IVIg may mediate the release of a variety of cytokines, the cytokines tested do not directly participate in the mechanism of IVIg action.
del Rey, Adriana; Roggero, Eduardo; Randolf, Anke; Mahuad, Carolina; McCann, Samuel; Rettori, Valeria; Besedovsky, Hugo O.
Administration of IL-1β results in a profound and long-lasting hypoglycemia. Here, we show that this effect can be elicited by endogenous IL-1 and is related to not only the capacity of the cytokine to increase glucose uptake in peripheral tissues but also to mechanisms integrated in the brain. We show that (i) blockade of IL-1 receptors in the brain partially counteracted IL-1-induced hypoglycemia; (ii) peripheral administration or induction of IL-1 production resulted in IL-1β gene expression in the hypothalamus of normal and insulin-resistant, leptin receptor-deficient, diabetic db/db mice; (iii) IL-1-treated normal and db/db mice challenged with glucose did not return to their initial glucose levels but remained hypoglycemic for several hours. This effect was largely antagonized by blockade of IL-1 receptors in the brain; and (iv) when animals with an advanced Type II diabetes were treated with IL-1 and challenged with glucose, they died in hypoglycemia. However, when IL-1 receptors in the brains of these diabetic mice were blocked, they survived, and glucose blood levels approached those that these mice had before IL-1 administration. The prolonged hypoglycemic effect of IL-1 is insulin-independent and develops against increased levels of glucocorticoids, catecholamines, and glucagon. These findings, together with the present demonstration that this effect is integrated in the brain and is paralleled by IL-1β expression in the hypothalamus, indicate that this cytokine can reset glucose homeostasis at central levels. Such reset, along with the peripheral actions of the cytokine, would favor glucose uptake by immune cells during inflammatory/immune processes. PMID:17035503
Kim, Mi-Young; Ilyosbek, Sattorov; Lee, Byung Ho; Yi, Kyu Yang; Jung, Yi-Sook
Urotensin II (U-II), the most potent vasoconstrictor peptide known to date, is expressed at a high level in vascular smooth muscle cells (VSMC) and endothelial cells, whereas its receptor, urotensin (UT) receptor, is abundant in monocytes and macrophages of atherosclerotic lesions. U-II is highly present in the coronary arteries of the atherosclerotic patients compared to normal subjects. Recently, U-II was shown to down-regulate ATP binding cassette transporter-A1 (ABCA1) expression, which is responsible for reverse cholesterol transport in macrophages of atherosclerotic lesions. However, the mechanism of this observation was not clearly elucidated. Previous studies also revealed that the proinflammatory cytokine interleukin-1β (IL-1β) repressed ABCA1 expression. To clarify the signaling pathway involved with respect to U-II-induced ABCA1 down-regulation, we investigated whether IL-1ß was involved. Our results provided that U-II repressed ABCA1 through an ERK/ IL-1ß pathway. We further demonstrated that U-II receptor antagonist KR-36676 decreased IL-1ß production and significantly led to a recovery of ABCA1 expression at both mRNA and protein levels. In previous investigations, U-II receptor antagonists have been shown to protect atherosclerosis in cell and animal models. Our results imply that U-II receptor antagonist KR-36676 might be a potent candidate for treating atherosclerosis, and leading to a recovery of ABCA1 expression, affected by the ERK/IL-1ß pathway. Copyright © 2017. Published by Elsevier B.V.
Iannitti, Rossana G.; Napolioni, Valerio; Oikonomou, Vasilis; De Luca, Antonella; Galosi, Claudia; Pariano, Marilena; Massi-Benedetti, Cristina; Borghi, Monica; Puccetti, Matteo; Lucidi, Vincenzina; Colombo, Carla; Fiscarelli, Ersilia; Lass-Flörl, Cornelia; Majo, Fabio; Cariani, Lisa; Russo, Maria; Porcaro, Luigi; Ricciotti, Gabriella; Ellemunter, Helmut; Ratclif, Luigi; De Benedictis, Fernando Maria; Talesa, Vincenzo Nicola; Dinarello, Charles A.; van de Veerdonk, Frank L.; Romani, Luigina
Dysregulated inflammasome activation contributes to respiratory infections and pathologic airway inflammation. Through basic and translational approaches involving murine models and human genetic epidemiology, we show here the importance of the different inflammasomes in regulating inflammatory responses in mice and humans with cystic fibrosis (CF), a life-threatening disorder of the lungs and digestive system. While both contributing to pathogen clearance, NLRP3 more than NLRC4 contributes to deleterious inflammatory responses in CF and correlates with defective NLRC4-dependent IL-1Ra production. Disease susceptibility in mice and microbial colonization in humans occurrs in conditions of genetic deficiency of NLRC4 or IL-1Ra and can be rescued by administration of the recombinant IL-1Ra, anakinra. These results indicate that pathogenic NLRP3 activity in CF could be negatively regulated by IL-1Ra and provide a proof-of-concept evidence that inflammasomes are potential targets to limit the pathological consequences of microbial colonization in CF. PMID:26972847
Iannitti, Rossana G; Napolioni, Valerio; Oikonomou, Vasilis; De Luca, Antonella; Galosi, Claudia; Pariano, Marilena; Massi-Benedetti, Cristina; Borghi, Monica; Puccetti, Matteo; Lucidi, Vincenzina; Colombo, Carla; Fiscarelli, Ersilia; Lass-Flörl, Cornelia; Majo, Fabio; Cariani, Lisa; Russo, Maria; Porcaro, Luigi; Ricciotti, Gabriella; Ellemunter, Helmut; Ratclif, Luigi; De Benedictis, Fernando Maria; Talesa, Vincenzo Nicola; Dinarello, Charles A; van de Veerdonk, Frank L; Romani, Luigina
Dysregulated inflammasome activation contributes to respiratory infections and pathologic airway inflammation. Through basic and translational approaches involving murine models and human genetic epidemiology, we show here the importance of the different inflammasomes in regulating inflammatory responses in mice and humans with cystic fibrosis (CF), a life-threatening disorder of the lungs and digestive system. While both contributing to pathogen clearance, NLRP3 more than NLRC4 contributes to deleterious inflammatory responses in CF and correlates with defective NLRC4-dependent IL-1Ra production. Disease susceptibility in mice and microbial colonization in humans occurs in conditions of genetic deficiency of NLRC4 or IL-1Ra and can be rescued by administration of the recombinant IL-1Ra, anakinra. These results indicate that pathogenic NLRP3 activity in CF could be negatively regulated by IL-1Ra and provide a proof-of-concept evidence that inflammasomes are potential targets to limit the pathological consequences of microbial colonization in CF.
eosinophilic cells. No specific IL-1 labeling was treated mice. We next evaluated whether the in vivo adminis- observed on erythroid cells. These results...granulopoiesis. Because the showed that most of the labeled cells belonged to the granu - administration of IL-1 induces an initial rapid mobilization of...and 16% of eosinophilic and mono- the differential expression of RB6-8C5 antigen on myeloid cytic cells exhibited a similar pattern of labeling with 7
Mortensen, Martin; Iqbal, Favaad; Pandurangan, Arun P; Hannan, Saad; Huckvale, Rosemary; Topf, Maya; Baker, James R; Smart, Trevor G
Neurotransmitter receptor trafficking is fundamentally important for synaptic transmission and neural network activity. GABAA receptors and inhibitory synapses are vital components of brain function, yet much of our knowledge regarding receptor mobility and function at inhibitory synapses is derived indirectly from using recombinant receptors, antibody-tagged native receptors and pharmacological treatments. Here we describe the use of a set of research tools that can irreversibly bind to and affect the function of recombinant and neuronal GABAA receptors following ultraviolet photoactivation. These compounds are based on the competitive antagonist gabazine and incorporate a variety of photoactive groups. By using site-directed mutagenesis and ligand-docking studies, they reveal new areas of the GABA binding site at the interface between receptor β and α subunits. These compounds enable the selected inactivation of native GABAA receptor populations providing new insight into the function of inhibitory synapses and extrasynaptic receptors in controlling neuronal excitation.
Cucak, Helena; Hansen, Gitte; Vrang, Niels; Skarsfeldt, Torben; Steiness, Eva; Jelsing, Jacob
The cytokine interleukin-1β (IL-1β) is known to stimulate proinflammatory immune responses and impair β-cell function and viability, all critical events in the pathogenesis of type 1 diabetes (T1D). Here we evaluate the effect of SER140, a small peptide IL-1β receptor antagonist, on diabetes progression and cellular pancreatic changes in female nonobese diabetic (NOD) mice. Eight weeks of treatment with SER140 reduced the incidence of diabetes by more than 50% compared with vehicle, decreased blood glucose, and increased plasma insulin. Additionally, SER140 changed the endocrine and immune cells dynamics in the NOD mouse pancreas. Together, the data suggest that SER140 treatment postpones the onset of diabetes in female NOD mice by interfering with IL-1β activated pathways. PMID:26953152
Lan, Kuo-Mao; Tien, Lu-Tai; Pang, Yi; Bhatt, Abhay J; Fan, Lir-Wan
We have previously reported that neonatal lipopolysaccharide (LPS) exposure resulted in an increase in interleukin-1β (IL-1β) content, injury to the hippocampus, and cognitive deficits in juvenile male and female rats, as well as female adult rats. The present study aimed to determine whether an anti-inflammatory cytokine, interleukin-1 receptor antagonist (IL-1ra), protects against the neonatal LPS exposure-induced inflammatory responses, hippocampal injury, and long-lasting learning deficits in adult rats. LPS (1 mg/kg) or LPS plus IL-1ra (0.1 mg/kg) was injected intracerebrally to Sprague-Dawley male rat pups at postnatal day 5 (P5). Neurobehavioral tests were carried out on P21, P49, and P70, while neuropathological studies were conducted on P71. Our results showed that neonatal LPS exposure resulted in learning deficits in rats at both developmental and adult ages, as demonstrated by a significantly impaired performance in the passive avoidance task (P21, P49, and P70), reduced hippocampal volume, and reduced number of Nissl+ cells in the CA1 region of the middle dorsal hippocampus of P71 rat brain. Those neuropathological and neurobehavioral alterations by LPS exposure were associated with a sustained inflammatory response in the P71 rat hippocampus, indicated by increased number of activated microglia as well as elevated levels of IL-1β. Neonatal administration of IL-1ra significantly attenuated LPS-induced long-lasting learning deficits, hippocampal injury, and sustained inflammatory responses in P71 rats. Our study demonstrates that neonatal LPS exposure leads to a persistent injury to the hippocampus, resulting in long-lasting learning disabilities related to chronic inflammation in rats, and these effects can be attenuated with an IL-1 receptor antagonist.
Pang, Yi; Bhatt, Abhay J.; Fan, Lir-Wan
We have previously reported that neonatal lipopolysaccharide (LPS) exposure resulted in an increase in interleukin-1β (IL-1β) content, injury to the hippocampus, and cognitive deficits in juvenile male and female rats, as well as female adult rats. The present study aimed to determine whether an antiinflammatory cytokine, interleukin-1 receptor antagonist (IL-1ra), protects against the neonatal LPS exposure-induced inflammatory responses, hippocampal injury, and long-lasting learning deficits in adult rats. LPS (1 mg/kg) or LPS plus IL-1ra (0.1 mg/kg) was injected intracerebrally to Sprague-Dawley male rat pups at postnatal day 5 (P5). Neurobehavioral tests were carried out on P21, P49, and P70, while neuropathological studies were conducted on P71. Our results showed that neonatal LPS exposure resulted in learning deficits in rats at both developmental and adult ages, as demonstrated by a significantly impaired performance in the passive avoidance task (P21, P49, and P70), reduced hippocampal volume, and reduced number of Nissl+ cells in the CA1 region of the middle dorsal hippocampus of P71 rat brain. Those neuropathological and neurobehavioral alterations by LPS exposure were associated with a sustained inflammatory response in the P71 rat hippocampus, indicated by increased number of activated microglia as well as elevated levels of IL-1β. Neonatal administration of IL-1ra significantly attenuated LPS-induced long-lasting learning deficits, hippocampal injury, and sustained inflammatory responses in P71 rats. Our study demonstrates that neonatal LPS exposure leads to a persistent injury to the hippocampus, resulting in long-lasting learning disabilities related to chronic inflammation in rats, and these effects can be attenuated with an IL-1 receptor antagonist. PMID:25665855
Androgen receptor antagonism by the organophosphate insecticide fenitrothion. Tamura, H., Maness, S.C., Reischmann, K. Dorman, D.C., Gray, L.E., and Gaido, K.W. (2000). Toxicol. Sci.
Organophosphate insecticides represent one of the most widely used classes of pesticide...
Androgen receptor antagonism by the organophosphate insecticide fenitrothion. Tamura, H., Maness, S.C., Reischmann, K. Dorman, D.C., Gray, L.E., and Gaido, K.W. (2000). Toxicol. Sci.
Organophosphate insecticides represent one of the most widely used classes of pesticide...
Kovach, Melissa A; Stringer, Kathleen A; Bunting, Rachel; Wu, Xiaoying; San Mateo, Lani; Newstead, Michael W; Paine, Robert; Standiford, Theodore J
Acute respiratory distress syndrome (ARDS) is a disease associated with a high mortality rate. The initial phase is characterized by induction of inflammatory cytokines and chemokines and influx of circulating inflammatory cells, including macrophages which play a pivotal role in the innate and adaptive immune responses to injury. Growing evidence points to phenotypic heterogeneity and plasticity between various macrophage activation states. In this study, gene expression in alveolar macrophages and circulating leukocytes from healthy control subjects and patients with ARDS was assessed by mRNA microarray analysis. Both alveolar macrophages and circulating leukocytes demonstrated up-regulation of genes encoding chemotactic factors, antimicrobial peptides, chemokine receptors, and matrix metalloproteinases. Two genes, the pro-inflammatory S100A12 and the anti-inflammatory IL-1 decoy receptor IL-1R2 were significantly induced in both cell populations in ARDS patients, which was confirmed by protein quantification. Although S100A12 levels did not correlate with disease severity, there was a significant association between early plasma levels of IL-1R2 and APACHE III scores at presentation. Moreover, higher levels of IL-1R2 in plasma were observed in non-survivors as compared to survivors at later stages of ARDS. These results suggest a hybrid state of alveolar macrophage activation in ARDS, with features of both alternative activation and immune tolerance/deactivation.. Furthermore, we have identified a novel plasma biomarker candidate in ARDS that correlates with the severity of systemic illness and mortality.
Rodan, S.B.; Wesolowski, G.; Chin, J.; Limjuco, G.A.; Schmidt, J.A.; Rodan, G.A. )
IL-1 is a potent bone resorbing agent. Its mechanism of action is unknown, but the presence of osteoblasts was shown to be necessary for IL-1 stimulation of bone resorption by isolated osteoclasts. This study examines the presence of IL-1R and IL-1 effects in osteoblastic cells from a clonal human osteosarcoma cell line, Saos-2/B-10. We found that the binding affinity and the number of binding sites increases substantially during the postconfluent stage. Scatchard and curve-fitting analysis revealed one class of high affinity binding sites, with Kd/Ki's of 40 +/- 17 pM (mean +/- SD) for IL-1 alpha (n = 5) and 9 +/- 7 pM for IL-1 beta (n = 5) and 2916 +/- 2438 (n = 6) receptors/cell. Incubation of the cells with 125I-IL-1 alpha (100 pM) at 4 degrees C, followed by incubation at 37 degrees C up to 4 h, revealed internalization of receptor-bound IL-1 alpha. Chemical cross-linking studies showed that the IL-1R in Saos-2/B-10 cells had a molecular mass of approximately 80 kDa. To assess the biologic effect of IL-1 in Saos-2/B-10 cells, we determined PGE2 content and adenylate cyclase activity. Although IL-1 had no effect on PGE2 synthesis, both IL-1 alpha and IL-1 beta enhanced PGE2 stimulation of adenylate cyclase two- to four-fold in a dose-dependent manner. The half-maximal effect for IL-1 alpha was seen at 8 to 10 pM and for IL-1 beta at 0.6 to 1.8 pM. IL-1 did not enhance basal adenylate cyclase or stimulation by parathyroid hormone, isoproterenol, or forskolin. IL-1 enhancement of PGE2-stimulated adenylate cyclase was detected between 1 to 2 h, was maximal at 4 to 5 h, was not prevented by cycloheximide treatment, and was seen in membranes from IL-1 pretreated cells. These data show effects of IL-1 on a human osteoblast-like cell line that are mediated by high affinity receptors. These IL-1 effects could contribute to the biologic action of IL-1 on bone.
Saadat, Habibollah; Ziai, Seyed Ali; Ghanemnia, Maryam; Namazi, Mohammad Hasan; Safi, Morteza; Vakili, Hosein; Dabbagh, Ali; Gholami, Omid
There is evidence that opium addiction has immunosuppressant effects. Coronary artery disease (CAD) is a condition resulted from atherosclerosis which is dependent on the immune response. To evaluate plasma levels of interleukin-6 and interleukin-1Ra in 30 patients with three-vessel coronary artery disease, ejection fraction of more than 35% and to evaluate their changes after prognostic treadmill test in 15 opium addicted and 15 non-addicted patients. The participants underwent prognostic treadmill test and plasma levels of interleukin-6 (IL-6) and interleukin-1Ra (IL-1Ra) were evaluated with ELISA method before, just after and 4 hours after the test. IL-1Ra (2183 pg/ml) tended to decrease over time in the opium addicted group (1372 pg/ml after prognostic treadmill test and 1034 pg/ml 4 hours after that), although such decrease did not reach the statistical significance. IL-1Ra levels were significantly higher in opium addicted than in non addicted patients. Opium addiction had no significant effect on IL-6 changes. Consumption of opium in CAD patients is associated with higher IL-1Ra levels.
Saadat, Habibollah; Ziai, Seyed Ali; Ghanemnia, Maryam; Namazi, Mohammad Hasan; Safi, Morteza; Vakili, Hosein; Dabbagh, Ali; Gholami, Omid
Background There is evidence that opium addiction has immunosuppressant effects. Coronary artery disease (CAD) is a condition resulted from atherosclerosis which is dependent on the immune response. Purpose To evaluate plasma levels of interleukin-6 and interleukin-1Ra in 30 patients with three-vessel coronary artery disease, ejection fraction of more than 35% and to evaluate their changes after prognostic treadmill test in 15 opium addicted and 15 non-addicted patients. Methods The participants underwent prognostic treadmill test and plasma levels of interleukin-6 (IL-6) and interleukin-1Ra (IL-1Ra) were evaluated with ELISA method before, just after and 4 hours after the test. Results IL-1Ra (2183 pg/ml) tended to decrease over time in the opium addicted group (1372 pg/ml after prognostic treadmill test and 1034 pg/ml 4 hours after that), although such decrease did not reach the statistical significance. IL-1Ra levels were significantly higher in opium addicted than in non addicted patients. Opium addiction had no significant effect on IL-6 changes. Conclusion Consumption of opium in CAD patients is associated with higher IL-1Ra levels. PMID:23028694
Jefferies, C; Bowie, A; Brady, G; Cooke, E L; Li, X; O'Neill, L A
We have examined the involvement of components of the interleukin-1 (IL-1) signaling pathway in the transactivation of gene expression by the p65 subunit of NF-kappaB. Transient transfection of cells with plasmids encoding wild-type MyD88, IL-1 receptor-associated kinase 1 (IRAK-1), and TRAF-6 drove p65-mediated transactivation. In addition, dominant negative forms of MyD88, IRAK-1, and TRAF-6 inhibited the IL-1-induced response. In cells lacking MyD88 or IRAK-1, no effect of IL-1 was observed. Together, these results indicate that MyD88, IRAK-1, and TRAF-6 are important downstream regulators of IL-1-mediated p65 transactivation. We have previously shown that the low-molecular-weight G protein Rac1 is involved in this response. Constitutively active RacV12-mediated transactivation was not inhibited by dominant negative MyD88, while dominant negative RacN17 inhibited the MyD88-driven response, placing Rac1 downstream of MyD88 on this pathway. Dominant negative RacN17 inhibited wild-type IRAK-1- and TRAF-6-induced transactivation, and in turn, dominant negative IRAK-1 and TRAF-6 inhibited the RacV12-driven response, suggesting a mutual codependence of Rac1, IRAK-1, and TRAF-6 in regulating this pathway. Finally, Rac1 was found to associate with the receptor complex via interactions with both MyD88 and the IL-1 receptor accessory protein. A pathway emanating from MyD88 and involving IRAK-1, TRAF-6, and Rac1 is therefore involved in transactivation of gene expression by the p65 subunit of NF-kappaB in response to IL-1.
Skinner, Camille M; Ivanov, Nikita S; Barr, Sarah A; Chen, Yan; Skalsky, Rebecca L
Epstein-Barr virus (EBV) encodes >44 viral microRNAs (miRNAs) that are differentially expressed throughout infection, can be detected in EBV-positive tumors, and manipulate several biological processes including cell proliferation, apoptosis, and immune responses. Here, we show that EBV BHRF1-2 miRNAs block NF-kB activation following treatment with pro-inflammatory cytokines, specifically interleukin-1 beta. Analysis of EBV PAR-CLIP miRNA targetome datasets combined with pathway analysis revealed multiple BHRF1-2 miRNA targets involved in interleukin signaling pathways. By further analyzing changes in cellular gene expression patterns, we identified the interleukin-1 receptor 1 (IL1R1) as a direct target of miR-BHRF1-2-5p. Targeting of the IL1R1 3' UTR by EBV miR-BHRF1-2-5p was confirmed using 3' UTR luciferase reporter assays and western blot assays. Manipulation of EBV BHRF1-2 miRNA activity in latently-infected B cells altered steady-state cytokine levels and disrupted IL-1β responsiveness. These studies demonstrate functionally relevant BHRF1-2 miRNA interactions during EBV infection, which is an important step in understanding their roles in pathogenesis.Importance IL-1 signaling plays an important role in inflammation and early activation of host innate immune responses following virus infection. Here, we demonstrate that a viral miRNA downregulates the IL-1 receptor 1 during EBV infection, which consequently alters the responsiveness of cells to IL-1 stimuli and changes the cytokine expression levels within infected cell populations. We postulate that this viral miRNA activity not only disrupts IL-1 autocrine and paracrine signaling loops that can alert effector cells to sites of infection, but also provides a survival advantage by dampening excessive inflammation that may be detrimental to the infected cell. Copyright © 2017 American Society for Microbiology.
Xiang, Shengnan; Su, Jing; Tong, Haijun; Yang, Fei; Tong, Wenxue; Yuan, Weien; Wu, Fei; Wang, Chuandong; Jin, Tuo; Dai, Kerong; Zhang, Xiaoling
Cytoxicity is an essential concern for polyethyleneimine 25 kDa (PEI 25 kDa), a widely reported, highly effective transfection agent used in gene delivery. In our recent experiments, Small molecular weight cross-linked poly(ethylene imine) by biscarbamate linkage (PEI-Bu) (Mn: 3278, Mw: 4289) can reduce target cell apoptosis induced by polycationic transfection, and has almost the same DNA condensation capability as PEI 25 kDa. PEI-Bu showed significantly higher activity and lower cytotoxicity than PEI 25 kDa in transfecting the anti-inflammatory cytokine interleukin-1 receptor antagonist (IL-1Ra) gene to rat synoviocytes, an optimal target for arthritis treatment. The expression of IL-1Ra in synoviocytes then suppresses the expression of metalloproteases 13 (MMP13) gene, which is responsible for cartilage destruction regulated by IL-1β in arthritis. In conclusion, PEI-Bu is a promising tool for delivering IL-1Ra gene to synoviocytes for arthritis therapy.
Conti, P; Bartle, L; Barbacane, R C; Reale, M; Placido, F C; Sipe, J
Serum amyloid A (SAA) protein is a major acute phase reactant in human and many other species. Infections and traumatic inflammation are characterized by a rapid increase of SAA; its concentration in the plasma may augment many-fold. Cytokines such as IL-1 and IL-6 are considered mediators of acute phase protein synthesis. The most accredited mechanism of action of IL-1 in inflammatory diseases is the stimulation of PGE2 release, which is highly dependent on the concentration of IL-1. In this study we found that human Hep 3B hepatoma cells treated with the combination of hrIL-6 (10ng/ml) plus hrIL-1 (1ng/ml) produced an augmentation in steady-state levels of SAA mRNA (87%) compared to hrIL-6 (10ng/ml) plus PGE2 (5 microM), which induced an increase of only 33%, compared to IL-6 alone, while cells treated with hrIL-6 plus PGE2 (0.5 microM) had a similar effect as hrIL-6 did alone. Moreover, the addition of exogenous PGE2 (5 microM) to the cell cultures produced no significant increase in concentration of SAA mRNA compared to the control. In addition, according to the data obtained by the blot analysis we also found, by ELISA method, that hrIL-6 acts in synergism with hrIL-1 on SAA protein secretion in human Hep 3B hepatoma cell cultures after 48 h incubation. In fact, the cell cultures treated with hrIL-6 plus hrIL-1 caused a higher release approximately 1.5-4-fold of SAA protein than the cells treated with IL-6 plus PGE2 5 microM or IL-1 + PGE2 5 microM, respectively. The synergistic effect of hrIL-6 plus hrIL-1 beta was inhibited by hrIL-1 receptor antagonist (hrIL-1ra) 50 micrograms/ml, a protein which specifically binds to the IL-1 receptor and is structurally similar to IL-1 beta but with no IL-1-like activity; while indomethacin (5 microM) was ineffective. These results strongly suggest that the synergism between hrIL-6 plus hrIL-1 on the transcription and the protein release of SAA release is not due to a PGE2-dependent process in human Hep 3B hepatoma cells
Selg, E; Buccellati, C; Andersson, M; Rovati, G E; Ezinga, M; Sala, A; Larsson, A-K; Ambrosio, E; Låstbom, L; Capra, V; Dahlén, B; Ryrfeldt, Å; Folco, G C; Dahlén, S-E
Background and purpose: Non-steroidal anti-inflammatory drugs (NSAIDs) are analgesic and anti-inflammatory by virtue of inhibition of the cyclooxygenase (COX) reaction that initiates biosynthesis of prostaglandins. Findings in a pulmonary pharmacology project gave rise to the hypothesis that certain members of the NSAID class might also be antagonists of the thromboxane (TP) receptor. Experimental approach: Functional responses due to activation of the TP receptor were studied in isolated airway and vascular smooth muscle preparations from guinea pigs and rats as well as in human platelets. Receptor binding and activation of the TP receptor was studied in HEK293 cells. Key results: Diclofenac concentration-dependently and selectively inhibited the contraction responses to TP receptor agonists such as prostaglandin D2 and U-46619 in the tested smooth muscle preparations and the aggregation of human platelets. The competitive antagonism of the TP receptor was confirmed by binding studies and at the level of signal transduction. The selective COX-2 inhibitor lumiracoxib shared this activity profile, whereas a number of standard NSAIDs and other selective COX-2 inhibitors did not. Conclusions and implications: Diclofenac and lumiracoxib, in addition to being COX unselective and highly COX-2 selective inhibitors, respectively, displayed a previously unknown pharmacological activity, namely TP receptor antagonism. Development of COX-2 selective inhibitors with dual activity as potent TP antagonists may lead to coxibs with improved cardiovascular safety, as the TP receptor mediates cardiovascular effects of thromboxane A2 and isoprostanes. PMID:17965743
Palmer, Gaby; Burger, Danielle; Mezin, Françoise; Magne, David; Gabay, Cem; Dayer, Jean-Michel; Guerne, Pierre-André
Leflunomide is an immunomodulatory agent used for the treatment of rheumatoid arthritis. In this study, we investigated the effect of A77 1726 - the active metabolite of leflunomide - on the production of IL-1 receptor antagonist (IL-1Ra) by human synovial fibroblasts and articular chondrocytes. Cells were incubated with A77 1726 alone or in combination with proinflammatory cytokines. IL-1Ra production was determined by ELISA. A77 1726 alone had no effect, but in the presence of IL-1beta or tumour necrosis factor-alpha it markedly enhanced the secretion of IL-1Ra in synovial fibroblasts and chondrocytes. The effect of A77 1726 was greatest at 100 micromol/l. In synovial fibroblasts and de-differentiated chondrocytes, A77 1726 also increased IL-1beta-induced IL-1Ra production in cell lysates. Freshly isolated chondrocytes contained no significant amounts of intracellular IL-1Ra. A77 1726 is a known inhibitor of pyrimidine synthesis and cyclo-oxygenase (COX)-2 activity. Addition of exogenous uridine did not significantly modify the effect of A77 1726 on IL-1Ra production, suggesting that it was not mediated by inhibition of pyrimidine synthesis. Indomethacin increased IL-1beta-induced IL-1Ra secretion in synovial fibroblasts and de-differentiated chondrocytes, suggesting that inhibition of COX-2 may indeed enhance IL-1beta-induced IL-1Ra production. However, the stimulatory effect of indomethacin was consistently less effective than that of A77 1726. A77 1726 increases IL-1Ra production by synovial fibroblasts and chondrocytes in the presence of proinflammatory cytokines, and thus it may possess chondroprotective effects. The effect of A77 1726 may be partially mediated by inhibition of COX-2, but other mechanisms likely concur to stimulate IL-1Ra production.
Kapelski, Pawel; Skibinska, Maria; Maciukiewicz, Malgorzata; Wilkosc, Monika; Frydecka, Dorota; Groszewska, Agata; Narozna, Beata; Dmitrzak-Weglarz, Monika; Czerski, Piotr; Pawlak, Joanna; Rajewska-Rager, Aleksandra; Leszczynska-Rodziewicz, Anna; Slopien, Agnieszka; Zaremba, Dorota; Twarowska-Hauser, Joanna
Schizophrenia has been associated with a large range of autoimmune diseases, with a history of any autoimmune disease being associated with a 45% increase in risk for the illness. The inflammatory system may trigger or modulate the course of schizophrenia through complex mechanisms influencing neurodevelopment, neuroplasticity and neurotransmission. In particular, increases or imbalance in cytokine before birth or during the early stages of life may affect neurodevelopment and produce vulnerability to the disease. A total of 27 polymorphisms of IL1N gene: rs1800587, rs17561; IL1B gene: rs1143634, rs1143643, rs16944, rs4848306, rs1143623, rs1143633, rs1143627; IL1RN gene: rs419598, rs315952, rs9005, rs4251961; IL6 gene: rs1800795, rs1800797; IL6R gene: rs4537545, rs4845617, rs2228145, IL10 gene: rs1800896, rs1800871, rs1800872, rs1800890, rs6676671; IL10RA gene: rs2229113, rs3135932; TGF1B gene: rs1800469, rs1800470; each selected on the basis of molecular evidence for functionality, were investigated in this study. Analysis was performed on a group of 621 patients with diagnosis of schizophrenia and 531 healthy controls in Polish population. An association of rs4848306 in IL1B gene, rs4251961 in IL1RN gene, rs2228145 and rs4537545 in IL6R with schizophrenia have been observed. rs6676671 in IL10 was associated with early age of onset. Strong linkage disequilibrium was observed between analyzed polymorphisms in each gene, except of IL10RA. We observed that haplotypes composed of rs4537545 and rs2228145 in IL6R gene were associated with schizophrenia. Analyses with family history of schizophrenia, other psychiatric disorders and alcohol abuse/dependence did not show any positive findings. Further studies on larger groups along with correlation with circulating protein levels are needed.
Nold-Petry, Claudia A; Lo, Camden Y; Rudloff, Ina; Elgass, Kirstin D; Li, Suzhao; Gantier, Michael P; Lotz-Havla, Amelie S; Gersting, Søren W; Cho, Steven X; Lao, Jason C; Ellisdon, Andrew M; Rotter, Björn; Azam, Tania; Mangan, Niamh E; Rossello, Fernando J; Whisstock, James C; Bufler, Philip; Garlanda, Cecilia; Mantovani, Alberto; Dinarello, Charles A; Nold, Marcel F
Interleukin 37 (IL-37) and IL-1R8 (SIGIRR or TIR8) are anti-inflammatory orphan members of the IL-1 ligand family and IL-1 receptor family, respectively. Here we demonstrate formation and function of the endogenous ligand-receptor complex IL-37-IL-1R8-IL-18Rα. The tripartite complex assembled rapidly on the surface of peripheral blood mononuclear cells upon stimulation with lipopolysaccharide. Silencing of IL-1R8 or IL-18Rα impaired the anti-inflammatory activity of IL-37. Whereas mice with transgenic expression of IL-37 (IL-37tg mice) with intact IL-1R8 were protected from endotoxemia, IL-1R8-deficient IL-37tg mice were not. Proteomic and transcriptomic investigations revealed that IL-37 used IL-1R8 to harness the anti-inflammatory properties of the signaling molecules Mer, PTEN, STAT3 and p62(dok) and to inhibit the kinases Fyn and TAK1 and the transcription factor NF-κB, as well as mitogen-activated protein kinases. Furthermore, IL-37-IL-1R8 exerted a pseudo-starvational effect on the metabolic checkpoint kinase mTOR. IL-37 thus bound to IL-18Rα and exploited IL-1R8 to activate a multifaceted intracellular anti-inflammatory program.
Elsaid, Khaled A; Ubhe, Anand; Shaman, Ziyad; D'Souza, Gerard
Interleukin-1 receptor antagonist (IL-1 ra) can be disease-modifying in posttraumatic osteoarthritis (PTOA). One limitation is its short joint residence time. We hypothesized that IL-1 ra encapsulation in poly (lactide-co-glycolide) (PLGA) microspheres reduces IL-1 ra systemic absorption and provides an enhanced anti-PTOA effect. IL-1 ra release kinetics and biological activity: IL-1 ra encapsulation into PLGA microsphere was performed using double emulsion solvent extraction. Lyophilized PLGA IL-1 ra microspheres were resuspended in PBS and supernatant IL-1 ra concentrations were assayed. The biological activity of IL-1 ra from PLGA IL-1 ra microspheres was performed using IL-1 induced lymphocyte proliferation and bovine articular cartilage degradation assays. Systemic absorption of IL-1 ra following intra-articular (IA) injection of PLGA IL-1 ra or IL-1 ra: At 1, 3, 6, 12 and 24 h following injection of 50 μl PLGA IL-1 ra (n = 6) or IL-1 ra (n = 6), serum samples were collected and IL-1 ra concentrations were determined. Anterior cruciate ligament transection (ACLT) and IA dosing: ACLT was performed in 8-10 week old male Lewis rats (n = 42). PBS (50 μl; n = 9), IL-1 ra (50 μl; 5 mg/ml; n = 13), PLGA IL-1 ra (50 μl; equivalent to 5 mg/ml IL-1 ra; n = 14) or PLGA particles (50 μl; n = 6) treatments were performed on days 7, 14, 21 and 28 following ACLT. Cartilage and synovial histopathology: On day 35, animal ACLT joints were harvested and tibial cartilage and synovial histopathology scoring was performed. Percent IL-1 ra content in the supernatant at 6 h was 13.44 ± 9.27 % compared to 34.16 ± 12.04 %, 47.89 ± 12.71 %, 57.14 ± 11.71 %, and 93.90 ± 8.50 % at 12, 24, 48 and 72 h, respectively. PLGA IL-1 ra inhibited lymphocyte proliferation and cartilage degradation similar to IL-1 ra. Serum IL-1 ra levels were significantly lower at 1, 3, and 6 h following PLGA IL-1 ra injection compared to IL
Hubers, Scott A.; Brown, Nancy J.
Heart failure affects approximately 5.7 million people in the United States alone. Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers, and aldosterone antagonists have improved mortality in patients with heart failure and reduced ejection fraction, but mortality remains high. In July 2015, the FDA approved the first of a new class of drugs for the treatment of heart failure; valsartan/sacubitril (formerly known as LCZ696 and currently marketed by Novartis as Entresto) combines the angiotensin receptor blocker valsartan and the neprilysin inhibitor prodrug sacubitril in a 1:1 ratio in a sodium supramolecular complex. Sacubitril is converted by esterases to LBQ657, which inhibits neprilysin, the enzyme responsible for the degradation of the natriuretic peptides and many other vasoactive peptides. Thus, this combined angiotensin receptor antagonist and neprilysin inhibitor addresses two of the pathophysiologic mechanisms of heart failure - activation of the renin-angiotensin-aldosterone system and decreased sensitivity to natriuretic peptides. In the Prospective comparison of ARNI with ACEI to Determine Impact on Global Mortality and morbidity in Heart Failure (PARADIGM-HF) trial, valsartan/sacubitril significantly reduced mortality and hospitalization for heart failure, as well as blood pressure, compared to enalapril in patients with heart failure, reduced ejection fraction, and an elevated circulating level of brain natriuretic peptide or N-terminal pro-brain natriuretic peptide. Ongoing clinical trials are evaluating the role of valsartan/sacubitril in the treatment of heart failure with preserved ejection fraction and hypertension. We review here the mechanisms of action of valsartan/sacubitril, the pharmacologic properties of the drug, and its efficacy and safety in the treatment of heart failure and hypertension. PMID:26976916
Hubers, Scott A; Brown, Nancy J
Heart failure affects ≈5.7 million people in the United States alone. Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, β-blockers, and aldosterone antagonists have improved mortality in patients with heart failure and reduced ejection fraction, but mortality remains high. In July 2015, the US Food and Drug Administration approved the first of a new class of drugs for the treatment of heart failure: Valsartan/sacubitril (formerly known as LCZ696 and currently marketed by Novartis as Entresto) combines the angiotensin receptor blocker valsartan and the neprilysin inhibitor prodrug sacubitril in a 1:1 ratio in a sodium supramolecular complex. Sacubitril is converted by esterases to LBQ657, which inhibits neprilysin, the enzyme responsible for the degradation of the natriuretic peptides and many other vasoactive peptides. Thus, this combined angiotensin receptor antagonist and neprilysin inhibitor addresses 2 of the pathophysiological mechanisms of heart failure: activation of the renin-angiotensin-aldosterone system and decreased sensitivity to natriuretic peptides. In the Prospective Comparison of ARNI With ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial, valsartan/sacubitril significantly reduced mortality and hospitalization for heart failure, as well as blood pressure, compared with enalapril in patients with heart failure, reduced ejection fraction, and an elevated circulating level of brain natriuretic peptide or N-terminal pro-brain natriuretic peptide. Ongoing clinical trials are evaluating the role of valsartan/sacubitril in the treatment of heart failure with preserved ejection fraction and hypertension. We review here the mechanisms of action of valsartan/sacubitril, the pharmacological properties of the drug, and its efficacy and safety in the treatment of heart failure and hypertension.
Carpintero, Rakel; Brandt, Karim J.; Gruaz, Lyssia; Molnarfi, Nicolas; Lalive, Patrice H.; Burger, Danielle
Glatiramer acetate (GA), an immunomodulator used in multiple sclerosis (MS) therapy, induces the production of secreted IL-1 receptor antagonist (sIL-1Ra), a natural inhibitor of IL-1β, in human monocytes, and in turn enhances sIL-1Ra circulating levels in MS patients. GA is a mixture of peptides with random Glu, Lys, Ala, and Tyr sequences of high polarity and hydrophilic nature that is unlikely to cross the blood–brain barrier. In contrast, sIL-1Ra crosses the blood–brain barrier and, in turn, may mediate GA anti-inflammatory activities within the CNS by counteracting IL-1β activities. Here we identify intracellular signaling pathways induced by GA that control sIL-1Ra expression in human monocytes. By using kinase knockdown and specific inhibitors, we demonstrate that GA induces sIL-1Ra production via the activation of PI3Kδ, Akt, MEK1/2, and ERK1/2, demonstrating that both PI3Kδ/Akt and MEK/ERK pathways rule sIL-1Ra expression in human monocytes. The pathways act in parallel upstream glycogen synthase kinase-3α/β (GSK3α/β), the knockdown of which enhances sIL-1Ra production. Together, our findings demonstrate the existence of signal transduction triggered by GA, further highlighting the mechanisms of action of this drug in MS. PMID:20876102
Chen, XuXin; Zhao, YunFeng; Wu, XueLing; Qian, GuiSheng
Single Ig IL-1 receptor-related molecule (SIGIRR) is one of the members of the Toll-like receptor (TLR)-IL-1 receptor superfamily. Previous studies demonstrated that SIGIRR can function as a negative regulator of IL-1 and LPS signaling. The purpose of this study was to evaluate the effect of enhanced expression of SIGIRR on LPS-induced acute lung injury. We constructed a recombinant adenoviral vector expressing murine SIGIRR (Ad.mSIGIRR) and a control adenoviral vector containing no transgene (Ad.V). A total of 4 × 10⁷ plaque-forming units of Ad.mSIGIRR or Ad.V adenoviral vector were administered intranasally to BALB/c mice. Forty-eight hours later, all the mice were administered a single dose of LPS via i.p. injection to induce lung injury. Lungs and blood were harvested at several time points. The expression of SIGIRR in lung, the histological changes in the lung, the levels of TNF-α in serum and lung, the concentration of nitric monoxide (NO) in lung, and the activity of myeloperoxidase and nuclear transcription factor κB in the lung were examined. A second cohort of mice was followed for survival for 7 days. Administration of Ad.mSIGIRR increased the expression of SIGIRR in lung tissue, as determined by reverse transcription-polymerase chain reaction, Western blot, and immunohistochemistry. Administration of Ad.mSIGIRR significantly suppressed the inflammatory reaction to LPS, attenuated the lung pathological changes, and improved the survival of mice, relative to a control adenovirus. These findings suggest that modulating the expression level of SIGIRR may be a promising potential treatment for acute lung injury.
Kennedy, Gregory D.; Nukaya, Manabu; Moran, Susan M.; Glover, Edward; Weinberg, Samuel; Balbo, Silvia; Hecht, Stephen S.; Pitot, Henry C.; Drinkwater, Norman R.; Bradfield, Christopher A.
We set out to better understand the signal transduction pathways that mediate liver tumor promotion by 2,3,7,8-tetrachlorodibenzo-p-dioxn (“dioxin”). To this end, we first employed congenic mice homozygous for either the Ahrb1 or Ahrd alleles (encoding an aryl hydrocarbon receptor (AHR) with high or low binding affinity for dioxin, respectively) and demonstrated that hepatocellular tumor promotion in response to dioxin segregated with the Ahr locus. Once we had genetic evidence for the importance of AHR signaling, we then asked if tumor promotion by dioxin was influenced by “interleukin-1 (IL-1)-like” inflammatory cytokines. The importance of this question arose from our earlier observation that aspects of the acute hepatocellular toxicity of dioxin are dependent upon IL1-like cytokine signaling. To address this issue, we employed a triple knock-out (TKO) mouse model with null alleles at the loci encoding the three relevant receptors for tumor necrosis factors α and β and IL-1α and IL-1β (i.e., null alleles at the Tnfrsf1a, Tnfrsf1b, and Il-1r1 loci). The observation that TKO mice were resistant to the tumor promoting effects of dioxin in liver suggests that inflammatory cytokines play an important step in dioxin mediated liver tumor promotion in the mouse. Collectively, these data support the idea that the mechanism of dioxin acute hepatotoxicity and its activity as a promoter in a mouse two stage liver cancer model may be similar, i.e., tumor promotion by dioxin, like acute hepatotoxicity, are mediated by the linked action of two receptor systems, the AHR and the receptors for the “IL-1-like” cytokines. PMID:24718703
Lavine, Jeremy A.; Sang, Yanzhi; Wang, Shoujian; Ip, Michael S.; Sheibani, Nader
Objectives To determine if β-adrenergic blockade inhibits choroidal neovascularization (CNV) in a mouse model of laser-induced CNV, and to investigate the mechanism by which β-adrenoreceptor antagonism blunts CNV. Methods The impact of β-adrenoreceptor blockade on CNV was determined using the laser-induced CNV model. Briefly, mice were subjected to laser burns, inducing CNV, and treated with daily intraperitoneal injections of propranolol. Neovascularization was measured on choroidal-sclera flat mounts using intercellular adhesion molecule-2 immunofluorescence staining. The impact of β-adrenergic receptor signaling on expression of vascular endothelial growth factor (VEGF) was investigated using primary mouse choroidal endothelial cells (ChEC) and retinal pigment epithelial (RPE) cells. These cells were incubated with β-adrenoreceptor agonists and/or antagonists, and assayed for VEGF mRNA and protein levels. Results Propranolol-treated mice demonstrated a 50% reduction in laser-induced CNV. Norepinephrine treatment stimulated VEGF mRNA expression and protein secretion in both ChEC and RPE cells. This effect was blocked by β2-adrenoreceptor antagonism and mimicked by β2-adrenergic receptor agonists. Conclusions and Clinical Relevance β-Adrenergic blockade attenuated CNV. β2-Adrenergic receptors regulated VEGF expression in ChEC and RPE cells. Antagonists of β-adrenergic receptors are safe and well tolerated in patients with glaucoma and cardiovascular disease. Thus, blockade of β-adrenoreceptors may provide a new avenue to inhibit VEGF expression in CNV. PMID:23303344
Bhatt, Suresh; Bhatt, Rekha; Zalcman, Steven S; Siegel, Allan
Feline defensive rage, a form of aggressive behavior that occurs in response to a threat can be elicited by electrical stimulation of the medial hypothalamus or midbrain periaqueductal gray (PAG). Our laboratory has recently begun a systematic examination of the role of cytokines in the regulation of rage and aggressive behavior. It was shown that the cytokine, interleukin-2 (IL-2), differentially modulates defensive rage when microinjected into the medial hypothalamus and PAG by acting through separate neurotransmitter systems. The present study sought to determine whether a similar relationship exists with respect to interleukin 1-beta (IL-1 beta), whose receptor activation in the medial hypothalamus potentiates defensive rage. Thus, the present study identified the effects of administration of IL-1 beta into the PAG upon defensive rage elicited from the medial hypothalamus. Microinjections of IL-1 beta into the dorsal PAG significantly facilitated defensive rage behavior elicited from the medial hypothalamus in a dose and time dependent manner. In addition, the facilitative effects of IL-1 beta were blocked by pre-treatment with anti-IL-1 beta receptor antibody, while IL-1 beta administration into the PAG had no effect upon predatory attack elicited from the lateral hypothalamus. The findings further demonstrated that IL-1 beta's effects were mediated through 5-HT(2) receptors since pretreatment with a 5-HT(2C) receptors antagonist blocked the facilitating effects of IL-1 beta. An extensive pattern of labeling of IL-1 beta and 5-HT(2C) receptors in the dorsal PAG supported these findings. The present study demonstrates that IL-beta in the dorsal PAG, similar to the medial hypothalamus, potentiates defensive rage behavior and is mediated through a 5-HT(2C) receptor mechanism.
Feng, Tian; Yunfeng, Ni; Jinbo, Zhao; Zhipei, Zhang; Huizhong, Zhang; Li, Liu; Tao, Jiang; Yunjie, Wang
The lipopolysaccharide (LPS)-Toll-like receptor 4 (TLR4) signaling pathway in alveolar epithelial cells plays an important role in many pathologic processes such as acute lung injury (ALI). The single immunoglobulin IL-1 receptor-related protein (SIGIRR) is an inhibitor of LPS-TLR4 signaling, but its expression and function in alveolar epithelial cells are still unknown. In this study, we examined the expression of SIGIRR in normal human lung tissue using immunohistochemistry, reverse transcription-PCR (RT-PCR) and Western blot and found that SIGIRR was expressed in alveolar epithelial cells. Treatment of an alveolar epithelial cell line, A549, with LPS and we observed a downregulation of SIGIRR mRNA, which returned to normal levels 24h after LPS exposure. A549 cells were then transfected with a SIGIRR eukaryotic expression vector to over-express SIGIRR or, as a control, with an empty vector. Following LPS exposure, the transcriptional activity of NF-kappaB was measured using a dual-luciferase reporter assay system, and the concentration of IL-1beta, TNF-alpha and IL-6 was determined by ELISA, and cell proliferation was measured by MTT. In A549 cells that over-expressed SIGIRR, LPS treatment resulted in a significant decrease in the transcriptional activity of NF-kappaB and cell growth inhibition ratio, as well as lower levels of secreted IL-1beta, TNF-alpha and IL-6. In conclusion, SIGIRR in A549 cells inhibits the transcriptional activity of NF-kappaB and reduces the amount cytokines produced, protecting these cells from acute LPS-induced damage. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.
Yoshida, Tomoyuki; Yasumura, Misato; Uemura, Takeshi; Lee, Sung-Jin; Ra, Moonjin; Taguchi, Ryo; Iwakura, Yoichiro; Mishina, Masayoshi
Mental retardation (MR) and autism are highly heterogeneous neurodevelopmental disorders. IL-1-receptor accessory protein-like 1 (IL1RAPL1) is responsible for nonsyndromic MR and is associated with autism. Thus, the elucidation of the functional role of IL1RAPL1 will contribute to our understanding of the pathogenesis of these mental disorders. Here, we showed that knockdown of endogenous IL1RAPL1 in cultured cortical neurons suppressed the accumulation of punctate staining signals for active zone protein Bassoon and decreased the number of dendritic protrusions. Consistently, the expression of IL1RAPL1 in cultured neurons stimulated the accumulation of Bassoon and spinogenesis. The extracellular domain (ECD) of IL1RAPL1 was required and sufficient for the presynaptic differentiation-inducing activity, while both the ECD and cytoplasmic domain were essential for the spinogenic activity. Notably, the synaptogenic activity of IL1RAPL1 was specific for excitatory synapses. Furthermore, we identified presynaptic protein tyrosine phosphatase (PTP) δ as a major IL1RAPL1-ECD interacting protein by affinity chromatography. IL1RAPL1 interacted selectively with certain forms of PTPδ splice variants carrying mini-exon peptides in Ig-like domains. The synaptogenic activity of IL1RAPL1 was abolished in primary neurons from PTPδ knock-out mice. IL1RAPL1 showed robust synaptogenic activity in vivo when transfected into the cortical neurons of wild-type mice but not in PTPδ knock-out mice. These results suggest that IL1RAPL1 mediates synapse formation through trans-synaptic interaction with PTPδ. Our findings raise an intriguing possibility that the impairment of synapse formation may underlie certain forms of MR and autism as a common pathogenic pathway shared by these mental disorders.
Czopek, Alicja; Moorhouse, Rebecca; Webb, David J; Dhaun, Neeraj
Our growing understanding of the role of the endothelin (ET) system in renal physiology and pathophysiology is from emerging studies of renal disease in animal models and humans. ET receptor antagonists reduce blood pressure and proteinuria in chronic kidney disease and cause regression of renal injury in animals. However, the therapeutic potential of ET receptor antagonism has not been fully explored and clinical studies have been largely limited to patients with diabetic nephropathy. There remains a need for more work in nondiabetic chronic kidney disease, end-stage renal disease (patients requiring maintenance dialysis and those with a functioning kidney transplant), ischemia reperfusion injury, and sickle cell disease. The current review summarizes the most recent advances in both preclinical and clinical studies of ET receptor antagonists in the field of kidney disease. Copyright © 2016 the American Physiological Society.
Platania, Chiara Bianca Maria; Giurdanella, Giovanni; Di Paola, Luisa; Leggio, Gian Marco; Drago, Filippo; Salomone, Salvatore; Bucolo, Claudio
Diabetic retinopathy (DR) is the most frequent complication of diabetes and one of leading causes of blindness worldwide. Early phases of DR are characterized by retinal pericyte loss mainly related to concurrent inflammatory process. Recently, an important link between P2X7 receptor (P2X7R) and inflammation has been demonstrated indicating this receptor as potential pharmacological target in DR. Here we first carried out an in silico molecular modeling study in order to characterize the allosteric pocket in P2X7R, and identify a suitable P2X7R antagonist through molecular docking. JNJ47965567 was identified as the hit compound in docking calculations, as well as for its absorption, distribution, metabolism and excretion (ADME) profile. As an in vitro model of early diabetic retinopathy, human retinal pericytes were exposed to high glucose (25mM, 48h) that caused a significant (p<0.05) release of IL-1β and LDH. The block of P2X7R by JNJ47965567 significantly (p<0.05) reverted the damage elicited by high glucose, detected as IL-1β and LDH release. Overall, our findings suggest that the P2X7R represents an attractive pharmacological target to manage the early phase of diabetic retinopathy, and the compound JNJ47965567 is a good template to discover other P2X7R selective antagonists. Copyright © 2017 Elsevier Inc. All rights reserved.
Krumm, Brian; Xiang, Yan; Deng, Junpeng
Interleukin-1 superfamily of cytokines (IL-1, IL-18, IL-33) play key roles in inflammation and regulating immunity. The mechanisms of agonism and antagonism in the IL-1 superfamily have been pursued by structural biologists for nearly 20 years. New insights into these mechanisms were recently provided by the crystal structures of the ternary complexes of IL-1β and its receptors. We will review here the structural biology related to receptor recognition by IL-1 superfamily cytokines and the regulation of its cytokine activities by antagonists. PMID:24677376
Armstrong, R. A.; Jones, R. L.; Peesapati, V.; Will, S. G.; Wilson, N. H.
The inhibitory effects of three prostanoid analogues, EP 045, EP 092 and pinane thromboxane A2 (PTA2), on the aggregation of human platelets in vitro have been investigated. In diluted platelet-rich plasma (PRP), EP 045 (20 microM) and EP 092 (1 microM) completely inhibited irreversible aggregation responses to thromboxane A2 (TXA2), prostaglandin H2 (PGH2) and five chemically stable thromboxane mimetics, including 11,9-epoxymethano-PGH2 and 9,11-azo-PGH2. Reversible aggregation produced by the prostanoid analogue, CTA2, was also inhibited. The block of the stable agonist action was surmountable. In plasma-free platelet suspensions EP 045 and EP 092 were more potent antagonists. Schild analysis indicated a competitive type of antagonism for EP 045 (affinity constant of 1.1 X 10(7) M-1); the nature of the EP 092 block is not clear. Primary aggregation waves induced by ADP, platelet activating factor (Paf) and adrenaline were unaffected by EP 045 and EP 092, whereas the corresponding second phases of aggregation were suppressed. Aggregation and 5-hydroxytryptamine (5-HT) release induced by either PGH2 or 11,9-epoxymethano-PGH2 were inhibited in a parallel manner by EP 045. Inhibition of thromboxane biosynthesis is not involved in these effects. EP 045 and EP 092 did not raise adenosine 3':5'-cyclic monophosphate (cyclic AMP) levels in the platelet suspensions. In plasma-free platelet suspensions PTA2 produced a shape change response which could be blocked by EP 045. PTA2, therefore, has a thromboxane-like agonist action. The block of the aggregatory action of 11,9-epoxymethano-PGH2 by PTA2 appears to be mainly due to competition at the thromboxane receptor. However, PTA2 produced a slight rise in cyclic AMP levels; this could be due to a very weak stimulant action on either PGI2 or PGD2 receptors present in the human platelet. Functional antagonism by PTA2 may therefore augment its thromboxane receptor blocking activity. The results are discussed in terms of (a) the
Benedetti, S; Randelli, E; Buonocore, F; Zou, J; Secombes, C J; Scapigliati, G
In this work we studied the biological activities of recombinant IL-1beta from the teleosts sea bass (Dicentrarchus labrax) and rainbow trout (Oncorhynchus mykiss) by investigating the effects induced on intracellular Ca2+ concentrations ([Ca2+]i) of spleen leucocytes. Splenocytes were loaded with the Ca2+-permeant Fura-2AM, and then stimulated with rIL-1beta. The emitted fluorescence was read for 5 min at 1 min intervals on a dual excitation fluorescence fluorimeter. Results showed that rIL-1beta induced in both species a rise in [Ca2+]i, and a subsequent decrease until 5 min after stimulation. The stimulating effect was dose-dependent in both species reaching a plateau at 200 ng/ml of rIL-1beta, was abolished by heat-treatment of rIL-1beta, and affected in a dose-dependent fashion by treatment of leucocytes with trypsin. These features suggested a functional IL-1 receptor was involved in the binding. The observed rise in [Ca2+]i was not detected in human PBMC and was species-specific, since rIL-1beta from sea bass, trout, and human were unable to interfere each other in the assay. Moreover, incubation of splenocytes with rIL-1beta induced a rapid tyrosine phosphorylation of a 24 kDa polypeptide in both species. This work represents the first evidence of a direct effect on [Ca2+]i induced by IL-1beta and suggests that in the evolution of IL-1 activities, teleost fishes display a peculiar IL-1-associated behaviour that is lacking in mammals.
Xiong, Juan; Burkovetskaya, Maria; Karpuk, Nikolay; Kielian, Tammy
Staphylococcus aureus is a common aetiological agent of bacterial brain abscesses. We have previously established that a considerable IL-1 (interleukin-1) response is elicited immediately following S. aureus infection, where the cytokine can exert pleiotropic effects on glial activation and blood–brain barrier permeability. To assess the combined actions of IL-1α and IL-1β during CNS (central nervous system) infection, host defence responses were evaluated in IL-1RI (IL-1 receptor type I) KO (knockout) animals. IL-1RI KO mice were exquisitely sensitive to intracerebral S. aureus infection, as demonstrated by enhanced mortality rates and bacterial burdens within the first 24 h following pathogen exposure compared with WT (wild-type) animals. Loss of IL-1RI signalling also dampened the expression of select cytokines and chemokines, concomitant with significant reductions in neutrophil and macrophage infiltrates into the brain. In addition, the opening of astrocyte hemichannels during acute infection was shown to be dependent on IL-1RI activity. Collectively, these results demonstrate that IL-1RI signalling plays a pivotal role in the genesis of immune responses during the acute stage of brain abscess development through S. aureus containment, inflammatory mediator production, peripheral immune cell recruitment, and regulation of astrocyte hemichannel activity. Taken in the context of previous studies with MyD88 (myeloid differentiation primary response gene 88) and TLR2 (Toll-like receptor 2) KO animals, the current report advances our understanding of MyD88-dependent cascades and implicates IL-1RI signalling as a major antimicrobial effector pathway during acute brain-abscess formation. PMID:22414156
Jespersen, Annie; Tajima, Nami; Fernandez-Cuervo, Gabriela; Garnier-Amblard, Ethel C.; Furukawa, Hiro
Summary There has been a great level of enthusiasm to down-regulate overactive N-methyl-d-aspartate (NMDA) receptors to protect neurons from excitotoxicity. NMDA receptors play pivotal roles in basic brain development and functions as well as in neurological disorders and diseases. However, mechanistic understanding of antagonism in NMDA receptors is limited due to complete lack of antagonist-bound structures for the l-glutamate-binding GluN2 subunits. Here we report the crystal structures of GluN1/GluN2A NMDA receptor ligand-binding domain (LBD) heterodimers in complex with GluN1- and GluN2-targeting antagonists. The crystal structures reveal that the antagonists, D-(−)-2-Amino-5-phosphonopentanoic acid (d-AP5) and 1-(Phenanthrene-2-carbonyl)piperazine-2,3-dicarboxylic acid (PPDA), have discrete binding modes and mechanisms for opening of the bilobed architecture of GluN2A LBD compared to the agonist-bound form. The current study shows distinct ways by which the conformations of NMDA receptor LBDs may be controlled and coupled to receptor inhibition and provides possible strategies to develop therapeutic compounds with higher subtype-specificity. PMID:24462099
Nguyen, Nam Trung; Nakahama, Taisuke; Nguyen, Chi Hung; Tran, Trang Thu; Le, Van Son; Chu, Hoang Ha; Kishimoto, Tadamitsu
Although rheumatoid arthritis (RA) is the most common autoimmune disease, affecting approximately 1% of the population worldwide, its pathogenic mechanisms are poorly understood. Tobacco smoke, an environmental risk factor for RA, contains several ligands of aryl hydrocarbon receptor (Ahr), also known as dioxin receptor. Ahr plays critical roles in the immune system. We previously demonstrated that Ahr in helper T-cells contributes to development of collagen-induced arthritis, a mouse model of RA. Other studies have shown that cigarette smoke condensate and pure Ahr ligands exacerbate RA by altering bone metabolism and inducing proinflammatory responses in fibroblast-like synoviocytes. Consistent with these findings, several Ahr antagonists such as α-naphthoflavone, resveratrol, and GNF351 reverse the effect of Ahr ligands in RA pathogenesis. In this review, we summarize the current knowledge of Ahr function in the immune system and the potential clinical benefits of Ahr antagonism in treating RA. PMID:27186143
Yin, Ling-Ling; Ruan, Su-Hong; Tian, Yu; Zhao, Kai; Xu, Kai Lin
To clone the variable region genes of human anti-IL1RAP (IL-1 receptor accessory protein) monoclonal antibodies (McAb) and to construct IL1RAP chimeric antigen receptors (CARs). The VH and VL DNA of IL1RAP single chain antibodies were amplified by RACE and overlap extension PCR from total RNA extracted from 3H6E10 and 10D8A7 hybridoma and ligated into specific IL1RAP single-chain variable fragments (scFv). CD8α transmembrane domain, CD137 intracellular domain, TCR ζ chain, human CD8α signal peptide and scFv-anti-IL1RAP were cloned into plasmid LV-lac. Recombinant lentiviruses were generated by co-transfection of recombinant plasmid LV-lac, pMD2. G, and psPAX2 helper vectors into 293FT packing cells. The VH and VL genes of 2 human anti-IL1RAP McAb were acquired. The 3H6E10 VH and VL genes consisted of 402 bp and 393 bp encoding 134 and 131 aminoacid residues, respectively; 10D8A7 VH and VL genes consisted of 423 bp and 381 bp encoding 141 and 127 amine acid residues, respectively. Recombinant expression vertors LV-3H6E10 scFv-ICD and LV-10D8A7 scFv-ICD (ICD: CD8α transmembrane domain-CD137 intracellular domain-TCR ζ chain) were constructed. The target fragments were demonstrated by sequencing analysis. Recombinant plasmids were transfected into 293FT cells and lentiviral particles were acquired. Human anti-IL1RAP recombinant receptors are constructed successfully and lay a good foundation for the construction of IL1RAP-CAR killer T cell vaccine.
McFarlane, C; Warner, D S; Todd, M M; Nordholm, L
Various subtypes of receptors have been identified for glutamate, an excitatory neurotransmitter. Previous studies have shown that antagonism of glutamate at the NMDA receptors reduces minimum alveolar concentration (MAC) for volatile anesthetics. NBQX (2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline) is a selective antagonist at the glutamatergic AMPA receptor. The purpose of this experiment was to determine whether AMPA receptor antagonism influences halothane MAC in the rat. Sprague-Dawley rats were anesthetized with halothane in 50% O2/balance N2, tracheally intubated and the lungs were mechanically ventilated. Increasing doses of NBQX were intravenously infused in three groups while the control group was infused with vehicle (D5W). Halothane MAC was then determined by the tail-clamp method. Halothane MAC was log-linearly related to plasma NBQX concentrations (MAC = 0.125 (In plasma concentration NBQX) + 1.035, r2 = 0.77). A maximal 58% reduction of halothane MAC was achieved with an NBQX loading dose of 42 mg/kg followed by a continuous infusion rate of 36 mg x kg-1 x h-1 (control = 1.02 +/- 0.07%; NBQX = 0.43 +/- 0.12%; P < .01). Larger doses of NBQX were not possible because of the poor aqueous solubility of this compound. In a separate experiment, awake rats were randomly assigned to groups based on the dose of NBQX infused. Pa(CO2) and mean arterial pressure were measured at time 0 and at 5 and 30 min after start of NBQX infusion. The infusion was then stopped. Time until recovery of the righting reflex was recorded.(ABSTRACT TRUNCATED AT 250 WORDS)
Honer, Christian; Nam, Kiyean; Fink, Cynthia; Marshall, Paul; Ksander, Gary; Chatelain, Ricardo E; Cornell, Wendy; Steele, Ronald; Schweitzer, Robert; Schumacher, Christoph
The steroid compound cyproterone acetate was identified in a high-throughput screen for glucocorticoid receptor (GR) binding compounds. Cyproterone (Schering AG) is clinically used as an antiandrogen for inoperable prostate cancer, virilizing syndromes in women, and the inhibition of sex drive in men. Despite its progestin properties, cyproterone shares a similar pharmacological profile with the antiprogestin mifepristone (RU486; Roussel Uclaf SA). The binding affinities of cyproterone and RU486 for the GR and progesterone receptor were similar (K(d), 15-70 nM). Both compounds were characterized as competitive antagonists of dexamethasone without intrinsic transactivating properties in rat hepatocytes (K(i), 10-30 nM). In osteosarcoma cells, RU486 revealed a higher potency than cyproterone acetate to prevent responses to dexamethasone-induced GR transactivation and NF kappa B transrepression. Upon administration to Sprague-Dawley rats, both compounds were found to be orally bioavailable and to inhibit transactivation of liver GR. Molecular docking of cyproterone acetate and RU486 into the homology model for the GR ligand binding domain illustrated overlapping steroid scaffolds in the binding pocket. However, in contrast to RU486, cyproterone lacks a bulky side chain at position C11 beta that has been proposed to trigger active antagonism of nuclear receptors by displacing the C-terminal helix of the ligand-binding domain, thereby affecting activation function 2. Cyproterone may therefore inhibit transactivation of the GR by a molecular mechanism recently described as passive antagonism. New therapeutic profiles may result from compounds designed to selectively stabilize the inactive and active conformations of certain nuclear receptors.
Ishino, Tetsuya; Harrington, Adrian E; Gopi, Hosahudya; Chaiken, Irwin
Human interleukin 5 (IL5) is the major hematopoietin that stimulates the proliferation, migration and activation of eosinophils and is implicated in the pathogenesis of inflammatory and other myeloproliferative diseases. IL5 functions through the signaling of a common receptor subunit beta (beta c), in a receptor activation process that requires initial recruitment of an IL5 specific receptor subunit alpha (IL5Ralpha), for cytokine presentation to beta c. Important advances have been made to understand molecular mechanisms of cytokine recognition and receptor antagonism. Mutational studies indicate that a pair of charge complementary regions play an essential role in specific interaction between IL5Ralpha and IL5. Moreover, peptide studies with the IL5 system have identified a cyclic peptide inhibitor, AF17121, which binds specifically to IL5Ralpha by mimicking the cytokine. A key receptor-recognition pharmacophore has been identified in this peptide inhibitor, and sites of inhibitor recognition can be proposed in the homology-deduced structural model of IL5Ralpha. These results provide an experimental platform to derive enhanced-potency peptidomimetic inhibitors. Such inhibitors have potential use as tools to evaluate the role of eosinophilia in disease and as potential leads to antagonists to treat hyper-eosinophilic diseases such as eosinophilic esophagitis, asthma and chronic myeloproliferative leukemias.
Jain, Ajay; Kaczanowska, Sabina; Davila, Eduardo
Chronic inflammation has long been associated with the development of cancer. Among the various signaling pathways within cancer cells that can incite the expression of inflammatory molecules are those that activate IL-1 receptor-associated kinases (IRAK). The IRAK family is comprised of four family members, IRAK-1, IRAK-2, IRAK-3 (also known as IRAK-M), and IRAK-4, which play important roles in both positively and negatively regulating the expression of inflammatory molecules. The wide array of inflammatory molecules that are expressed in response to IRAK signaling within the tumor microenvironment regulate the production of factors which promote tumor growth, metastasis, immune suppression, and chemotherapy resistance. Based on published reports we propose that dysregulated activation of the IRAK signaling pathway in cancer cells contributes to disease progression by creating a highly inflammatory tumor environment. In this article, we present both theoretical arguments and reference experimental data in support of this hypothesis.
Maroso, M; Balosso, S; Ravizza, T; Liu, J; Bianchi, M E; Vezzani, A
Inflammatory processes in brain tissue have been described in human epilepsy of various aetiologies and in experimental models of seizures. This, together with the anticonvulsant properties of anti-inflammatory therapies both in clinical and in experimental settings, highlights the important role of brain inflammation in the aetiopathogenesis of seizures. Preclinical investigations in experimental models using pharmacological and genetic tools have identified a significant contribution of interleukin-1 (IL-1) type 1 receptor/Toll-like receptor (IL-1R/TLR) signalling to seizure activity. This signalling can be activated by ligands associated with infections (pathogen-associated molecular patterns) or by endogenous molecules, such as proinflammatory cytokines (e.g. IL-1beta) or danger signals [damage-associated molecular patterns, e.g. high-mobility group box 1 (HMGB1)]. IL-1beta and HMGB1 are synthesized and released by astrocytes and microglia in the rodent brain during seizures. Notably, a rapid release of HMGB1 from neurons appears to be triggered by proconvulsant drugs even before seizure occurrence and is involved in their precipitation of seizures. The activation of IL-1R/TLR signalling mediates rapid post-translational changes in N-methyl-d-aspartate-gated ion channels in neurons. A long-term decrease in seizure threshold has also been observed, possibly mediated by transcriptional activation of genes contributing to molecular and cellular plasticity. This emerging evidence identifies specific targets with potential anticonvulsant effects in drug-resistant forms of epilepsy. © 2011 The Association for the Publication of the Journal of Internal Medicine.
Guan, Hong-Ping; Yang, Xiaodong; Lu, Ku; Wang, Sheng-Ping; Castro-Perez, Jose M.; Previs, Stephen; Wright, Michael; Shah, Vinit; Herath, Kithsiri; Xie, Dan; Szeto, Daphne; Forrest, Gail; Xiao, Jing Chen; Palyha, Oksana; Sun, Li-Ping; Andryuk, Paula J.; Engel, Samuel S.; Xiong, Yusheng; Lin, Songnian; Kelley, David E.; Erion, Mark D.; Davis, Harry R.; Wang, Liangsu
Glucagon and insulin have opposing action in governing glucose homeostasis. In type 2 diabetes mellitus (T2DM), plasma glucagon is characteristically elevated, contributing to increased gluconeogenesis and hyperglycemia. Therefore, glucagon receptor (GCGR) antagonism has been proposed as a pharmacologic approach to treat T2DM. In support of this concept, a potent small-molecule GCGR antagonist (GRA), MK-0893, demonstrated dose-dependent efficacy to reduce hyperglycemia, with an HbA1c reduction of 1.5% at the 80 mg dose for 12 weeks in T2DM. However, GRA treatment was associated with dose-dependent elevation of plasma LDL-cholesterol (LDL-c). The current studies investigated the cause for increased LDL-c. We report findings that link MK-0893 with increased glucagon-like peptide 2 and cholesterol absorption. There was not, however, a GRA-related modulation of cholesterol synthesis. These findings were replicated using structurally diverse GRAs. To examine potential pharmacologic mitigation, coadministration of ezetimibe (a potent inhibitor of cholesterol absorption) in mice abrogated the GRA-associated increase of LDL-c. Although the molecular mechanism is unknown, our results provide a novel finding by which glucagon and, hence, GCGR antagonism govern cholesterol metabolism. PMID:26373568
Seminerio, Michael J; Robson, Matthew J; McCurdy, Christopher R; Matsumoto, Rae R
Methamphetamine is currently one of the most widely abused drugs worldwide, with hyperthermia being a leading cause of death in methamphetamine overdose situations. Methamphetamine-induced hyperthermia involves a variety of cellular mechanisms, including increases in hypothalamic interleukin-1 beta (IL-1β) expression. Methamphetamine also interacts with sigma receptors and previous studies have shown that sigma receptor antagonists mitigate many of the behavioral and physiological effects of methamphetamine, including hyperthermia. The purpose of the current study was to determine if the attenuation of methamphetamine-induced hyperthermia by the sigma receptor antagonists, AZ66 and SN79, is associated with a concomitant attenuation of IL-1β mRNA expression, particularly in the hypothalamus. Methamphetamine produced dose- and time-dependent increases in core body temperature and IL-1β mRNA expression in the hypothalamus, striatum, and cortex in male, Swiss Webster mice. Pretreatment with the sigma receptor antagonists, AZ66 and SN79, significantly attenuated methamphetamine-induced hyperthermia, but further potentiated IL-1β mRNA in the mouse hypothalamus when compared to animals treated with methamphetamine alone. These findings suggest sigma receptor antagonists attenuate methamphetamine-induced hyperthermia through a different mechanism from that involved in the modulation of hypothalamic IL-1β mRNA expression.
Jing, Tao; Wu, Li; Borgmann, Kathleen; Surendran, Sankar; Ghorpade, Anuja; Liu, Jianuo; Xiong, Huangui
Astrocytes play an important role in astrocyte-neuron homeostasis. In HIV-1-infected brain, interleukin 1 beta (IL-1β) activation of astrocytes contributes to neurodegeneration. However, the molecular mechanisms underlying IL-1β-activated-astrocytes-induced neurodegeneration in HIV-1-infected brain are largely unknown. We hypothesize that secretory factors from the activated astrocytes affect N-methyl-d-aspartate (NMDA) receptor, a major pathway implicated in HIV-1-associated neurodegeneration. To test this hypothesis, we studied effects of IL-1β-stimulated astrocyte conditioned medium (ACM+) for its ability to activate NR1a/NR2B receptors expressed on Xenopus oocytes. Astrocytes treated with IL-1β 20ng/ml for 24h induced CXCL8, CCL2, MMP1 and MMP7. Pressure ejection of the ACM(+) produced an inward current in NR1a/NR2B-expressing oocytes. The inward current produced by ACM(+) was blocked by NMDA receptor antagonist, APV but not by non-NMDA receptor antagonist, CNQX. These results suggest that IL-1β stimulated astrocytes activate NR1a/NR2B receptors which may have implications in HIV-1-associated neurodegeneration. Copyright © 2010 Elsevier Inc. All rights reserved.
Baskar, Shankar; Klein, Allan L.; Zeft, Andrew
Recurrent pericarditis is a complication of acute pericarditis in 20–30% of the patients and is usually idiopathic in nature. The underlying pathogenesis of this condition remains unclear, although immune-mediated mechanisms seem likely. A subgroup of these patients with refractory symptoms can be challenging to manage, and multiple immunosuppressive medications have been used without consistent benefit. Anakinra, an interleukin-1 receptor antagonist, has been used in treatment of rheumatoid arthritis and autoinflammatory syndromes. Preliminary evidence suggests that anakinra could be a promising therapy for idiopathic recurrent pericarditis. In this narrative review, we summarize the current understanding of the etiopathogenesis of idiopathic recurrent pericarditis, mechanism of action of anakinra, and the preliminary evidence, supporting the use of anakinra in pericarditis. PMID:26942035
Current strategies for the treatment of hereditary angioedema (HAE) include targeted inhibition or antagonism of the contact system, which is dysregulated in HAE patients by a C1 esterase inhibitor deficiency. Ecallantide, a plasma kallikrein inhibitor, and icatibant, a selective bradykinin-2 receptor antagonist, have recently been evaluated in clinical studies for the treatment of acute HAE attacks. Both drugs have demonstrated evidence of efficacy and safety in treating acute HAE episodes, with ecallantide approved for use in the United States and icatibant approved for use in Europe. As therapeutic options for HAE expand for both for prophylactic and acute treatment strategies, a number of patient-specific and drug-specific factors have emerged as important considerations when developing individualized HAE management plans. Optimization of HAE therapy will require further integration of new therapies into the current treatment paradigm. PMID:23282868
Khan, Mohammed A; Steiner, Theodore S; Sham, Ho Pan; Bergstrom, Kirk S; Huang, Jingtian T; Assi, Kiran; Salh, Bill; Tai, Isabella T; Li, Xiaoxia; Vallance, Bruce A
Intestinal epithelial cells (IECs) are constantly exposed to enteric microbes. Although IECs express TLRs that recognize bacterial products, the activation of these TLRs is strictly controlled through poorly understood mechanisms, producing a state of hyporesponsiveness and preventing unwanted inflammation. The single IgG IL-1-related receptor (Sigirr) is a negative regulator of TLRs that is expressed by IECs and was recently shown to inhibit experimental colitis. However, the importance of Sigirr in IEC hyporesponsiveness and its distribution within the human colon is unknown. In this study, we investigated the role of Sigirr in regulating epithelial-specific TLR responses and characterized its expression in colonic biopsy specimens. Transformed and nontransformed human IECs were cultured as monolayers. Transient gene silencing and stable overexpression of Sigirr was performed to assess innate IEC responses. Sigirr expression in human colonic biopsy specimens was examined by immunohistochemistry. Bacterial infection of IECs and exposure to flagellin transiently decreased Sigirr protein expression, concurrent with secretion of the neutrophil chemokine IL-8. Sigirr gene silencing augmented chemokine responses to bacterial flagellin, Pam3Cys, and the cytokine IL-1beta. Conversely, stable overexpression of Sigirr diminished NF-kappaB-mediated IL-8 responses to TLR ligands. We also found that Sigirr expression increased as IECs differentiated in culture. This observation was confirmed in biopsy sections, in which Sigirr expression within colonic crypts was prominent in IECs at the apex and diminished at the base. Our findings show that Sigirr broadly regulates innate responses in differentiated human IECs; therefore, it may modulate epithelial involvement in infectious and inflammatory bowel diseases.
Ben-Menachem-Zidon, Ofra; Ben Menachem-Zidon, Ofra; Ben-Menahem, Yair; Ben-Hur, Tamir; Yirmiya, Raz
Ample evidence implicates neuroinflammatory processes in the etiology and progression of Alzheimer's disease (AD). To assess the specific role of the pro-inflammatory cytokine interleukin-1 (IL-1) in AD we examined the effects of intra-hippocampal transplantation of neural precursor cells (NPCs) with transgenic over-expression of IL-1 receptor antagonist (IL-1raTG) on memory functioning and neurogenesis in a murine model of AD (Tg2576 mice). WT NPCs- or sham-transplanted Tg2576 mice, as well as naive Tg2576 and WT mice served as controls. To assess the net effect of IL-1 blockade (not in the context of NPCs transplantation), we also examined the effects of chronic (4 weeks) intra-cerebroventricular (i.c.v.) administration of IL-1ra. We report that 12-month-old Tg2576 mice exhibited increased mRNA expression of hippocampal IL-1β, along with severe disturbances in hippocampal-dependent contextual and spatial memory as well as in neurogenesis. Transplantation of IL-1raTG NPCs 1 month before the neurobehavioral testing completely rescued these disturbances and significantly increased the number of endogenous hippocampal cells expressing the plasticity-related molecule BDNF. Similar, but less-robust effects were also produced by transplantation of WT NPCs and by i.c.v. IL-1ra administration. NPCs transplantation produced alterations in hippocampal plaque formation and microglial status, which were not clearly correlated with the cognitive effects of this procedure. The results indicate that elevated levels of hippocampal IL-1 are causally related to some AD-associated memory disturbances, and provide the first example for the potential use of genetically manipulated NPCs with anti-inflammatory properties in the treatment of AD.
Ali, R A; Saber, L M; Al-Harbi, A M
The Interleukin-1 receptor antagonist (IL1-Ra) is initiated to terminate the acute pro-inflammatory event and prevent chronic inflammation from damaging healthy cells. We aim to draw the attention of IL1-Ra (VNTR) gene polymorphism and determine whether IL1-Ra confer susceptibility to type 1 diabetes mellitus (T1DM) and evaluate the genotype and allele distribution of IL1-Ra gene in a Saudi population. Case control study included (100) T1DM Saudi children, plus 102 healthy unrelated individuals as control group. They were evaluated for variable number of tandem repeat (VNTR) of IL1-Ra gene polymorphism. Polymerase chain reaction amplification of VNTR of 86bp in intron 2 of IL1-Ra was performed. A1A1 and A1A2 genotypes with alleles A1 and A2 frequency were the most common both in cases and controls (healthy population); prevalence (28%, 56% & 57.8%, 39.2% respectively) and (58%, 38% and 77.5%, 22.5% respectively). In addition IL1-Ra gene polymorphism had higher risk significantly different between diabetic children and controls. (A1/A2) genotype had higher frequency statistically significant in DM patients than controls [56% vs. 39.2%, p < 0.02] and had twice time risk [OR = 1.97, 95% CI = 1.1-3.4, p < 0.02]. With further stratification, there was strong association between diabetic patients carriage IL1-Ra (A2) allele and controls [38% vs. 22.5%, p = 0.001] which had higher risk [OR = 2.11, 95% CI = 1.4-3.2, p = 0.001] for susceptibility of diabetes. This study emphasizes a positive association between IL1-Ra (VNTR) polymorphism and DM among Saudi children. This may suggest that (A2) allele may play important role in disease susceptibility.
Gao, Jin; Li, Jingjing; Yang, Minmin; Wu, Mingyuan; Tu, Ping; Yu, Yan; Han, Wei
To determine the incidence of the positive neutralizing anti-human interleukin receptor antagonist (anti-IL-1Ra), a novel assay based on the proliferation of human melanoma A375.S2 cells was developed and validated. In the presence of a growth-limiting concentration of IL-1β, A375.S2 cells were able to regain proliferation following the addition of IL-1Ra in a concentration-dependent manner. This dose-response effect enabled the validation of a standard curve for calculation of the concentration of IL-1Ra or, inversely, the concentration of neutralizing anti-IL-1Ra antibodies in cell culture medium or sera. The assay used CCK-8 as an indicator of proliferation. The dose-response relationship between rhIL-1Ra (dose range of 5-75 ng/ml rhIL-1Ra) and A375.S2 cell proliferation was sigmoidal and fitted a four-parameter logistic model. The percent coefficients of variation (%CVs) of quality control samples were 12.5 and 11.9% for intra-assay repeatability and 14.5 and 19.5% for inter-assay repeatability, while the total accuracy was in the range of 97.2-103.6%. For the neutralization assay, the optimal sample dilution factor was found to be 40-fold and the reasonable standard for positive and negative decision was calculated to be 59.4% neutralization rate. The %CVs of quality control samples were 12.7 and 24.0% for intra-assay repeatability and 11.6 and 30.0% for inter-assay repeatability. Analysis using the assay showed that rats could produce neutralizing anti-IL-1Ra antibodies after repeated intramuscular injection with rhIL-1Ra, and this response was not significantly dependent on the dose injected.
Shirazi, Rozita; Palsdottir, Vilborg; Collander, Jim; Anesten, Fredrik; Vogel, Heike; Langlet, Fanny; Jaschke, Alexander; Schürmann, Annette; Prévot, Vincent; Shao, Ruijin; Jansson, John-Olov; Skibicka, Karolina Patrycja
Glucagon-like peptide 1 (GLP-1), produced in the intestine and the brain, can stimulate insulin secretion from the pancreas and alleviate type 2 diabetes. The cytokine interleukin-6 (IL-6) may enhance insulin secretion from β-cells by stimulating peripheral GLP-1 production. GLP-1 and its analogs also reduce food intake and body weight, clinically beneficial actions that are likely exerted at the level of the CNS, but otherwise are poorly understood. The cytokines IL-6 and interleukin 1β (IL-1β) may exert an anti-obesity effect in the CNS during health. Here we found that central injection of a clinically used GLP-1 receptor agonist, exendin-4, potently increased the expression of IL-6 in the hypothalamus (11-fold) and the hindbrain (4-fold) and of IL-1β in the hypothalamus, without changing the expression of other inflammation-associated genes. Furthermore, hypothalamic and hindbrain interleukin-associated intracellular signals [phosphorylated signal transducer and activator of transcription-3 (pSTAT3) and suppressor of cytokine signaling-1 (SOCS1)] were also elevated by exendin-4. Pharmacologic disruption of CNS IL-1 receptor or IL-6 biological activity attenuated anorexia and body weight loss induced by central exendin-4 administration in a rat. Simultaneous blockade of IL-1 and IL-6 activity led to a more potent attenuation of exendin-4 effects on food intake. Mice with global IL-1 receptor gene knockout or central IL-6 receptor knockdown showed attenuated decrease in food intake and body weight in response to peripheral exendin-4 treatment. GLP-1 receptor activation in the mouse neuronal Neuro2A cell line also resulted in increased IL-6 expression. These data outline a previously unidentified role of the central IL-1 and IL-6 in mediating the anorexic and body weight loss effects of GLP-1 receptor activation.
Wang, Zhan-Kui; Ni, Guang-Xia; Liu, Kun; Xiao, Zhen-Xin; Yang, Bao-Wang; Wang, Jing; Wang, Shu
To explore the intervention timing of acupuncture in treatment of cerebral infarction and the relationship of cerebral ischemia reperfusion injury with inflammatory cytokine receptor. One hundred and ten male healthy Wistar rats were randomly divided into a normal group (n=10), a sham operation group (n=10), a model group (n=10), an acupuncture at non-acupoint group (non-acupoint group, n=40), an acupuncture with regaining consciousness method group (regaining consciousness group, n=40). Four subgroups were set up 1 h ischemia reperfusion in 1 h group, 3 h group, 6 h group, 12 h group in the two acupuncture groups, 10 rats in each subgroup. Two acupuncture groups were treated with acupuncture at four time points (1 h, 3 h, 6 h and 12 h after ischemia reperfusion), and "Shuigou" (GV 26) and "Neiguan" (PC 6) were selected in regaining consciousness group, and the non-acupoints below the bilateral costal region were selected in non-acupoint group. At the corresponding time point, the tissues of the brain were removed and interleukin1 receptor (IL-1RI) and tumor necrosis factor receptor (TNFR-I) mRNA and protein changes were detected by using real-time quantitative polymerase chain reaction and immunoblot assay. The expression of IL-1RI and TNFR-I mRNA and protein in the model group were significantly higher than that in normal group, sham operation group, regaining consciousness group and non-acupoint group (P<0.01, P<0.05). The expression of IL-1RI and TNFR-I mRNA and protein in regaining consciousness group was weakest at 3 h after reperfusion followed successively by 6 h, 1 h, 12 h, and there was no significantly change of IL-1RI and TNFR-I mRNA and protein expression in non-acupoint group among different timing points, but which was decreased as compared with those in the model group at the same time point (all P<0.05). Acupuncture can reduce the expression of IL-1RI and TNFR-I mRNA and protein in rats with cerebral ischemia reperfusion, inhibit the excessive
Vambutas, Andrea; DeVoti, James; Goldofsky, Elliot; Gordon, Michael; Lesser, Martin; Bonagura, Vincent
Autoimmune Inner Ear Disease (AIED) is poorly characterized clinically, with no definitive laboratory test. All patients suspected of having AIED are given glucocorticoids during periods of acute hearing loss, however, only half initially respond, and still fewer respond over time. We hypothesized that AIED is a systemic autoimmune disease characterized by dysfunctional peripheral blood mononuclear cells (PBMC) responses to a unique cochlear antigen(s). To test this hypothesis, we examined end-stage AIED patients undergoing cochlear implant surgery and compared autologous perilymph stimulated PBMC from AIED patients to controls. We determined that autologous perilymph from AIED patients was unable to induce expression of a long membrane-bound Interleukin-1 Receptor Type II (mIL1R2) transcript in PBMC as compared with controls, despite similar expression of the short soluble IL1R2 (sIL1R2) transcript (p<0.05). IL1R2 is a molecular decoy that traps interleukin-1β (IL-1β) and does not initiate subsequent signaling events, thereby suppressing an inflammatory response. IL1R2 transcript length is regulated by alternate splicing, and the major inhibitory function is attributed to the full-length mIL1R2. In addition, IL1R2 expression is induced by dexamethasone. Separately, we prospectively examined patients with newer onset glucocorticoid-responsive AIED. Immediately prior to clinical treatment for acute deterioration of hearing thresholds, their PBMC demonstrated a robust induction of mIL1R2 in PBMC in response to dexamethasone in vitro that correlated with a clinical response to prednisone in vivo (p<0.0001) as measured by hearing restoration. In contrast, clinically steroid unresponsive patients demonstrated high basal levels of mIL1R2 in their PBMC and only minimally augmented expression in response to dexamethasone. Thus, induced expression of mIL1R2 appears to be a protective mechanism in hearing homeostasis and warrants further investigation in a large
Russell, Shane E; Stefanska, Anna M; Kubica, Malgorzata; Horan, Rachel M; Mantovani, Alberto; Garlanda, Cecilia; Fallon, Padraic G; Walsh, Patrick T
Expression of the orphan receptor Toll IL-1R8/single Ig IL-1-related receptor has been reported to be reduced in the peripheral blood of psoriatic arthritis patients. However whether TIR8/SIGIRR activity plays a specific role in regulating psoriatic inflammation is unknown. We report that Tir8/Sigirr-deficient mice develop more severe psoriatic inflammation in both the chemical (Aldara)- and cytokine (rIL-23)-induced models of psoriasis. Increased disease severity was associated with enhanced infiltration of Vγ4⁺ γδ T cells that express significantly elevated levels of IL-17A. Critically, we also demonstrate that TIR8/SIGIRR activity directly suppressed innate IL-17A expression by γδ T cells in vitro and in vivo. Importantly, treatment of Tir8/Sigirr⁻/⁻ mice with an IL-17A neutralization Ab reversed the enhanced disease severity observed in these mice. This study identifies TIR8/SIGIRR as a novel intrinsic negative regulator of innate IL-17A expression and characterizes a novel mechanism involved in the regulation of psoriatic inflammation.
Cottone, Pietro; Wang, Xiaofan; Park, Jin Won; Valenza, Marta; Blasio, Angelo; Kwak, Jina; Iyer, Malliga R; Steardo, Luca; Rice, Kenner C; Hayashi, Teruo; Sabino, Valentina
Binge eating disorder is an addiction-like disorder characterized by episodes of rapid and excessive food consumption within discrete periods of time which occur compulsively despite negative consequences. This study was aimed at determining whether antagonism of Sigma-1 receptors (Sig-1Rs) blocked compulsive-like binge eating. We trained male wistar rats to obtain a sugary, highly palatable diet (Palatable group) or a regular chow diet (Chow control group), for 1 h a day under fixed ratio 1 operant conditioning. Following intake stabilization, we evaluated the effects of the selective Sig-1R antagonist BD-1063 on food responding. Using a light/dark conflict test, we also tested whether BD-1063 could block the time spent and the food eaten in an aversive, open compartment, where the palatable diet was offered. Furthermore, we measured Sig-1R mRNA and protein expression in several brain areas of the two groups, 24 h after the last binge session. Palatable rats rapidly developed binge-like eating, escalating the 1 h intake by four times, and doubling the eating rate and the regularity of food responding, compared to Chow rats. BD-1063 dose-dependently reduced binge-like eating and the regularity of food responding, and blocked the increased eating rate in Palatable rats. In the light/dark conflict test, BD-1063 antagonized the increased time spent in the aversive compartment and the increased intake of the palatable diet, without affecting motor activity. Finally, Palatable rats showed reduced Sig-1R mRNA expression in prefrontal and anterior cingulate cortices, and a two-fold increase in Sig-1R protein expression in anterior cingulate cortex compared to control Chow rats. These findings suggest that the Sig-1R system may contribute to the neurobiological adaptations driving compulsive-like eating, opening new avenues of investigation towards pharmacologically treating binge eating disorder.
Cottone, Pietro; Wang, Xiaofan; Park, Jin Won; Valenza, Marta; Blasio, Angelo; Kwak, Jina; Iyer, Malliga R; Steardo, Luca; Rice, Kenner C; Hayashi, Teruo; Sabino, Valentina
Binge eating disorder is an addiction-like disorder characterized by episodes of rapid and excessive food consumption within discrete periods of time which occur compulsively despite negative consequences. This study was aimed at determining whether antagonism of Sigma-1 receptors (Sig-1Rs) blocked compulsive-like binge eating. We trained male wistar rats to obtain a sugary, highly palatable diet (Palatable group) or a regular chow diet (Chow control group), for 1 h a day under fixed ratio 1 operant conditioning. Following intake stabilization, we evaluated the effects of the selective Sig-1R antagonist BD-1063 on food responding. Using a light/dark conflict test, we also tested whether BD-1063 could block the time spent and the food eaten in an aversive, open compartment, where the palatable diet was offered. Furthermore, we measured Sig-1R mRNA and protein expression in several brain areas of the two groups, 24 h after the last binge session. Palatable rats rapidly developed binge-like eating, escalating the 1 h intake by four times, and doubling the eating rate and the regularity of food responding, compared to Chow rats. BD-1063 dose-dependently reduced binge-like eating and the regularity of food responding, and blocked the increased eating rate in Palatable rats. In the light/dark conflict test, BD-1063 antagonized the increased time spent in the aversive compartment and the increased intake of the palatable diet, without affecting motor activity. Finally, Palatable rats showed reduced Sig-1R mRNA expression in prefrontal and anterior cingulate cortices, and a two-fold increase in Sig-1R protein expression in anterior cingulate cortex compared to control Chow rats. These findings suggest that the Sig-1R system may contribute to the neurobiological adaptations driving compulsive-like eating, opening new avenues of investigation towards pharmacologically treating binge eating disorder. PMID:22713906
McCormick, Allyson V.; Wheeler, Jeanna M.; Guthrie, Chris R.; Liachko, Nicole F.; Kraemer, Brian C.
Background Tauopathies, including Alzheimer’s disease (AD) and frontotemporal dementia, are diseases characterized by the formation of pathological tau protein aggregates in the brain and progressive neurodegeneration. Presently no effective disease modifying treatments exist for tauopathies. Methods To identify drugs targeting tau neurotoxicity, we have used a C. elegans model of tauopathy to screen a drug library containing 1120 compounds approved for human use for the ability to suppress tau-induced behavioral effects. Results One compound, the typical antipsychotic azaperone, improved the motility of tau transgenic worms, reduced levels of insoluble tau, and was protective against neurodegeneration. We found that azaperone reduces insoluble tau in a human cell culture model of tau aggregation, and that other antipsychotic drugs (flupenthixol, perphenazine, and zotepine) also ameliorate the effects of tau expression in both models. Conclusions Reduction of dopamine signaling through the dopamine D2 receptor with the use of gene knockouts in C. elegans or RNAi knockdown in human cell culture have similar protective effects against tau toxicity. These results suggest dopamine D2 receptor antagonism holds promise as a potential neuroprotective strategy for targeting tau aggregation and neurotoxicity. PMID:23140663
Akitsu, Aoi; Ishigame, Harumichi; Kakuta, Shigeru; Chung, Soo-hyun; Ikeda, Satoshi; Shimizu, Kenji; Kubo, Sachiko; Liu, Yang; Umemura, Masayuki; Matsuzaki, Goro; Yoshikai, Yasunobu; Saijo, Shinobu; Iwakura, Yoichiro
Interleukin-17 (IL-17)-producing γδ T (γδ17) cells have been implicated in inflammatory diseases, but the underlying pathogenic mechanisms remain unclear. Here, we show that both CD4+ and γδ17 cells are required for the development of autoimmune arthritis in IL-1 receptor antagonist (IL-1Ra)-deficient mice. Specifically, activated CD4+ T cells direct γδ T-cell infiltration by inducing CCL2 expression in joints. Furthermore, IL-17 reporter mice reveal that the Vγ6+ subset of CCR2+ γδ T cells preferentially produces IL-17 in inflamed joints. Importantly, because IL-1Ra normally suppresses IL-1R expression on γδ T cells, IL-1Ra-deficient mice exhibit elevated IL-1R expression on Vγ6+ cells, which play a critical role in inducing them to produce IL-17. Our findings demonstrate a pathogenic mechanism in which adaptive and innate immunity induce an autoimmune disease in a coordinated manner. PMID:26108163
Furlan, R; Bergami, A; Brambilla, E; Butti, E; De Simoni, M G; Campagnoli, M; Marconi, P; Comi, G; Martino, G
Primary proinflammatory cytokines, such as IL-1beta, play a crucial pathogenic role in multiple sclerosis and its animal model experimental autoimmune encephalomyelitis (EAE), and may represent, therefore, a suitable therapeutic target. We have previously established the delivery of anti-inflammatory cytokine genes within the central nervous system (CNS), based on intracisternal (i.c.) injection of non-replicative HSV-1-derived vectors. Here we show the therapeutic efficacy of i.c. administration of an HSV-1-derived vector carrying the interleukin-1receptor antagonist (IL-1ra) gene, the physiological antagonist of the proinflammatory cytokine IL-1, in C57BL/6 mice affected by myelin oligodendrocyte glycoprotein-induced EAE. IL-1ra gene therapy is effective preventively, delaying EAE onset by almost 1 week (22.4+/-1.4 days post-immunization vs 15.9+/-2.1 days in control mice; P=0.0229 log-rank test), and decreasing disease severity. Amelioration of EAE course was associated with a reduced number of macrophages infiltrating the CNS and in a decreased level of proinflammatory cytokine mRNA in the CNS, suggesting an inhibitory activity of IL-1ra on effector cell recruitment, as antigen-specific peripheral T-cell activation and T-cell recruitment to the CNS is unaffected. Thus, local IL-1ra gene therapy may represent a therapeutic alternative for the inhibition of immune-mediated demyelination of the CNS.
Watanabe, K; Uchida, K; Chambers, J K; Tei, M; Shoji, A; Ushio, N; Nakayama, H
The incidence of AA amyloidosis is high in humans with rheumatoid arthritis and several animal species, including cats and cattle with prolonged inflammation. AA amyloidosis can be experimentally induced in mice using severe inflammatory stimuli and a coinjection of AA amyloid; however, difficulties have been associated with transmitting AA amyloidosis to a different animal species, and this has been attributed to the "species barrier." The interleukin-1 receptor antagonist knockout (IL-1raKO) mouse, a rodent model of human rheumatoid arthritis, has been used in the transmission of AA amyloid. When IL-1raKO and BALB/c mice were intraperitoneally injected with mouse AA amyloid together with a subcutaneous pretreatment of 2% AgNO3, all mice from both strains that were injected with crude or purified murine AA amyloid developed AA amyloidosis. However, the amyloid index, which was determined by the intensity of AA amyloid deposition, was significantly higher in IL-1raKO mice than in BALB/c mice. When IL-1raKO and BALB/c mice were injected with crude or purified bovine AA amyloid together with the pretreatment, 83% (5/6 cases) and 38% (3/8 cases) of IL-1raKO mice and 17% (1/6 cases) and 0% (0/6 cases) of BALB/c mice, respectively, developed AA amyloidosis. Similarly, when IL-1raKO and BALB/c mice were injected with crude or purified feline AA amyloid, 33% (2/6 cases) and 88% (7/8 cases) of IL-1raKO mice and 0% (0/6 cases) and 29% (2/6 cases) of BALB/c mice, respectively, developed AA amyloidosis. These results indicated that IL-1raKO mice are a useful animal model for investigating AA amyloidogenesis. © The Author(s) 2014.
Peng, Jian; Tao, Xin; Li, Rui; Hu, Jingru; Ruan, Jie; Wang, Ruihua; Yang, Manyi; Yang, Rirong; Dong, Xiangru; Chen, Shangwu; Xu, Anlong; Yuan, Shaochun
Studies have shown that the basal chordate amphioxus possesses an extraordinarily complex TLR system, including 39 TLRs and at least 40 Toll/IL-1R homologous region (TIR) adaptors. Besides homologs to MyD88 and TIR domain-containing adaptor molecule (TICAM), most amphioxus TIR adaptors exhibit domain architectures that are not observed in other species. To reveal how these novel TIR adaptors function in amphioxus Branchiostoma belcheri tsingtauense (bbt), four representatives, bbtTIRA, bbtTIRB, bbtTIRC, and bbtTIRD, were selected for functional analyses. We found bbtTIRA to show a unique inhibitory role in amphioxus TICAM-mediated pathway by interacting with bbtTICAM and bbt receptor interacting protein 1b, whereas bbtTIRC specifically inhibits the amphioxus MyD88-dependent pathway by interacting with bbtMyD88 and depressing the polyubiquitination of bbt TNFR-associated factor 6. Although both bbtTIRB and bbtTIRD are located on endosomes, the TIR domain of bbtTIRB can interact with bbtMyD88 in the cytosol, whereas the TIR domain of bbtTIRD is enclosed in endosome, suggesting that bbtTIRD may be a redundant gene in amphioxus. This study indicated that most expanded TIR adaptors play nonredundant regulatory roles in amphioxus TLR signaling, adding a new layer to understanding the diversity and complexity of innate immunity at basal chordate.
Lech, Maciej; Avila-Ferrufino, Alejandro; Allam, Ramanjaneyulu; Segerer, Stephan; Khandoga, Alexander; Krombach, Fritz; Garlanda, Cecilia; Mantovani, Alberto; Anders, Hans-Joachim
Ischemia-reperfusion (IR) triggers tissue injury by activating innate immunity, for example, via TLR2 and TLR4. Surprisingly, TLR signaling in intrinsic renal cells predominates in comparison to intrarenal myeloid cells in the postischemic kidney. We hypothesized that immune cell activation is specifically suppressed in the postischemic kidney, for example, by single Ig IL-1-related receptor (SIGIRR). SIGIRR deficiency aggravated postischemic acute renal failure in association with increased renal CXCL2/MIP2, CCL2/MCP-1, and IL-6 mRNA expression 24 h after IR. Consistent with this finding interstitial neutrophil and macrophage counts were increased and tubular cell necrosis was aggravated in Sigirr-deficient vs wild-type IR kidneys. In vivo microscopy revealed increased leukocyte transmigration in the postischemic microvasculature of Sigirr-deficient mice. IL-6 and CXCL2/MIP2 release was much higher in Sigirr-deficient renal myeloid cells but not in Sigirr-deficient tubular epithelial cells after transient hypoxic culture conditions. Renal IR studies with chimeric mice confirmed this finding, as lack of SIGIRR in myeloid cells largely reproduced the phenotype of renal IR injury seen in Sigirr(-/-) mice. Additionally, clodronate depletion of dendritic cells prevented the aggravated renal failure in Sigirr(-/-) mice. Thus, loss of function mutations in the SIGIRR gene predispose to acute renal failure because SIGIRR prevents overshooting tissue injury by suppressing the postischemic activation of intrarenal myeloid cells.
Kroon, Jan; Puhr, Martin; Buijs, Jeroen T; van der Horst, Geertje; Hemmer, Daniëlle M; Marijt, Koen A; Hwang, Ming S; Masood, Motasim; Grimm, Stefan; Storm, Gert; Metselaar, Josbert M; Meijer, Onno C; Culig, Zoran; van der Pluijm, Gabri
Resistance to docetaxel is a major clinical problem in advanced prostate cancer (PCa). Although glucocorticoids (GCs) are frequently used in combination with docetaxel, it is unclear to what extent GCs and their receptor, the glucocorticoid receptor (GR), contribute to the chemotherapy resistance. In this study, we aim to elucidate the role of the GR in docetaxel-resistant PCa in order to improve the current PCa therapies. GR expression was analyzed in a tissue microarray of primary PCa specimens from chemonaive and docetaxel-treated patients, and in cultured PCa cell lines with an acquired docetaxel resistance (PC3-DR, DU145-DR, and 22Rv1-DR). We found a robust overexpression of the GR in primary PCa from docetaxel-treated patients and enhanced GR levels in cultured docetaxel-resistant human PCa cells, indicating a key role of the GR in docetaxel resistance. The capability of the GR antagonists (RU-486 and cyproterone acetate) to revert docetaxel resistance was investigated and revealed significant resensitization of docetaxel-resistant PCa cells for docetaxel treatment in a dose- and time-dependent manner, in which a complete restoration of docetaxel sensitivity was achieved in both androgen receptor (AR)-negative and AR-positive cell lines. Mechanistically, we demonstrated down-regulation of Bcl-xL and Bcl-2 upon GR antagonism, thereby defining potential treatment targets. In conclusion, we describe the involvement of the GR in the acquisition of docetaxel resistance in human PCa. Therapeutic targeting of the GR effectively resensitizes docetaxel-resistant PCa cells. These findings warrant further investigation of the clinical utility of the GR antagonists in the management of patients with advanced and docetaxel-resistant PCa.
Nishida, Atsushi; Andoh, Akira; Imaeda, Hirotsugu; Inatomi, Osamu; Shiomi, Hisanori; Fujiyama, Yoshihide
Interleukin 33 (IL33) is a cytokine belonging to the IL1 family and it binds to a complex of the ST2L/IL1 receptor accessory protein (IL1RAcP). To define the role of IL33 in fibrogenesis of the pancreas, the expression of IL33, ST2L and IL1RAcP was examined in chronic pancreatitis tissues. The effects of IL33 on the functions of human pancreatic myofibroblasts were also investigated. Tissue samples were obtained surgically. The expression of IL33, ST2L and IL1RAcP was evaluated by standard immunohistochemical procedures. Messenger RNA expression for IL33, ST2L and IL1RAcP was analysed by northern blotting and real-time PCR analyses, and protein expression was assessed by western blotting and ELISA. Cell proliferation and migration were assessed by a (3)H-thymidine incorporation assay and the modified Boyden chamber assay, respectively. IL33, ST2L and IL1RAcP were expressed by alpha-SMA-positive myofibroblasts in the fibrosis of chronic pancreatitis. In human pancreatic myofibroblasts, IL33 was weakly immunoexpressed without any stimuli, and this was markedly enhanced by IL1beta, tumour necrosis factor alpha (TNFalpha) and lipopolysaccharide (LPS) via the mitogen-activated protein kinase (MAPK)-dependent AP-1 activation pathway. ST2L mRNA was weakly detected in unstimulated cells, and IL4 and interferon gamma (IFNgamma) strongly enhanced ST2L expression via STAT6 and STAT1 signalling, respectively. IL33 rapidly induced the phosphorylation of MAPKs and IkappaBalpha, and enhanced the expression of inflammatory mediators (IL6, IL8, IP-10, Gro-alpha, Gro-beta and MCP-1) in IL4- or IFNgamma-pretreated cells. IL33 stimulated the proliferation and migration of pancreatic myofibroblasts. IL33 and its receptor complex (ST2L and IL1RAcP) constitute a novel signalling system which may play an important role in the pathogenesis of chronic pancreatitis.
Nair, Rohini Ravindran; Khanna, Anuradha; Singh, Kiran
An appropriate ratio of interleukin 1 beta to interleukin 1 receptor antagonist (IL1Ra) is required for successful pregnancy. Our objective was to study the genetic association between IL1RN variable numbers of tandem repeat (VNTR) polymorphism and recurrent pregnancy loss (RPL). To analyze the association between IL1RN VNTR allele and RPL, we investigated the IL1RN VNTR polymorphism in 136 RPL patients and in 200 healthy control women. Meta-analysis on this polymorphism was conducted to support our findings. PCR based approach was used to analyze IL1RN VNTR polymorphism and it was further confirmed by sequencing. Systematic review and meta-analysis was done using electronic database (Pub-Med, Google Scholar and Ovid) up to February 27, 2013. This meta-analysis was assessed by comprehensive meta-analysis software version 2. For meta-analysis 549 cases and 1,450 controls were included. The frequency of IL1RN genotype 2/2 was significantly higher in RPL compared to control group (AORs 3.10, 95 % CI 1.58-6.11, p = 0.001). The presence of rare allele also increased the risk of RPL significantly (ORs 1.63, 95 % CI 1.16-2.29, p = 0.004). The meta-analysis stratified by ethnicity showed that individuals with allele 2 had increased risk of RPL (OR 1.29, 95 % CI 1.04-1.61, p = 0.01), in Asians population by using fixed model. However the data of the present study clearly suggests that IL1RN VNTR polymorphism is a genetic risk factor for pregnancy loss in the study population.
Casós, Kelly; Siguero, Laura; Fernández-Figueras, María-Teresa; León, Xavier; Sardá, María-Pilar; Vila, Luis; Camacho, Mercedes
Prostaglandin (PG) E(2) plays a key role in immune response, tumor progression and metastasis. We previously showed that macrovessel-derived endothelial cells do not produce PGE(2) enzymatically because they do not express the inducible microsomal PGE-synthase-1 (mPGES-1). Nevertheless, differences between macro- and micro-vessel-derived endothelial cells regarding arachidonic acid (AAc) metabolism profile have been reported. The present work was conducted to evaluate the expression of PGE(2)-pathway-related enzymes in human microvascular endothelial cells (HMVEC) in culture and to test the hypothesis that the tumor cell-HMVEC cross talk could increase mPGES-1 expression in HMVEC. We treated HMVEC in culture with human recombinant IL-1β. IL-1β induced PGE(2) release and COX-2 and mPGES-1 expression in terms of mRNA and protein, determined by real-time PCR and immunoblotting, respectively. HMVEC constitutively expressed mPGES-2 and cytosolic PGES (cPGES) and the IL-1β treatment did not modify their expression. PGE(2) synthesized by HMVEC from exogenous AAc was linked to mPGES-1 expression. Immunohistochemistry analysis confirmed mPGES-1 expression in microvessels in vivo. COX-2 and mPGES-1 were also induced in HMVEC by the conditioned medium from two squamous head and neck carcinoma cell lines. Conditioned medium from tumor cell cultures contained several cytokines including the IL-1β and IL-1α. Tumor cell-induced COX-2 and mPGES-1 in HMVEC was strongly inhibited by the IL-1-receptor antagonist, indicating the important implication of IL-1 in this effect. HMVEC could therefore contribute directly to PGE(2) formed in the tumor. Our findings support the concept that mPGES-1 could be a target for therapeutic intervention in patients with cancer. Copyright © 2011 Elsevier Inc. All rights reserved.
Han, Tao; Qin, Yanyu; Mou, Chenzhi; Wang, Min; Jiang, Meng; Liu, Bin
Seizures, which result from synchronized aberrant firing of neuronal populations, can cause long-term sequelae, such as epilepsy, cognitive and behavioral issues, in which the synaptic plasticity alteration may play an important role. Long-term potentiation (LTP) is a persistent increase in synaptic strength and is essential for learning and memory. In the present study, we first examined the alteration of cognitive impairments and synaptic plasticity in mice with seizures, then explored the underlying mechanism involving pro-inflammatory factors and PI3K/Akt pathway. The results demonstrated that: (1) PTZ-induced seizure impairs learning and memory in mice, indicated by Morris water maze test; (2) PTZ-induced seizure decreased LTP; (3) the mRNA expression of IL-1β, IL-6 and TNF-α in the hippocampus were increased in mice with seizures; (4) LTP was increased by IL-1β receptor antagonist anakinra, but not inhibitors of IL-6 or TNF-α receptor; (5) Antagonist of IL-1β receptor rescues deficits in learning and memory of mice with seizures through PI3K/Akt pathway. It is concluded that the IL-1β induced by PTZ-induced seizures may impair the synaptic plasticity alteration in hippocampus as well as learning and memory ability by PI3K/Akt signaling pathway. PMID:27830035
Luo, Li-Jun; Liu, Feng; Lin, Zhi-Kai; Xie, Yu-Feng; Xu, Jia-Li; Tong, Qing-Chun; Shu, Rong
Periodontal ligament (PDL) cells are fibroblasts that play key roles in tissue integrity, periodontal inflammation and tissue regeneration in the periodontium. The periodontal tissue destruction in periodontitis is mediated by host tissue-produced inflammatory cytokines, including interleukin-1β (IL-1β). Here, we report the expression of G protein-coupled receptor 30 (GPR30, also known as G protein-coupled estrogen receptor 1 GPER) in human PDL cells and its regulation by IL-1β. IL-1β-induced GPR30 expression in human PDL cells leads to the activation of multiple signaling pathways, including MAPK, NF-κB and PI3K. In contrast, genistein, an estrogen receptor ligand, postpones the activation of MAPKs induced by IL-1β. Moreover, the inhibition of GPR30 by G15, a GPR30-specific antagonist, eliminates this delay. Thus, genistein plays a role in the regulation of MAPK activation via GPR30, and GPR30 represents a novel target regulated by steroid hormones in PDL cells.
Layé, S; Lundkvist, J; Bartfai, T
We examined whether functional heterologous complexes between human IL-1RI (hIL-1RI) and murine IL-1R accessory protein (mIL-1RAcP) can be formed, utilizing human fibroblast HEK 293 cells and murine fibroblast C127 cells, nontransfected or stably transfected with hIL-1RI (C127-hIL-1RI), respectively. In non-transfected C127 cells, IL-1beta signalled through the mIL-1RI-mIL-1RAcP complex and activated NFkappaB p50/p65 heterodimers. In C127-hIL-1RI cells, IL-1beta signalled through the hIL-1RI and activated both p65/p65 and p50/p65 NFkappaB complexes, where only the activation of NFkappaB p65/p65 was dependent on mIL-1RAcP. Thus, clearly both homologous and heterologous IL-1RI-IL-1RAcP interactions support NFkappaB translocation, but with differences in signalling pattern.
Schroer, Alison K.; Chen, Peter; Ryzhova, Larisa M.; Gladson, Santhi; Shay, Sheila; Hutcheson, Joshua D.; Merryman, W. David
Serotonergic anorexigens are the primary pharmacologic risk factor associated with pulmonary arterial hypertension (PAH), and the resulting PAH is clinically indistinguishable from the heritable form of disease, associated with BMPR2 mutations. Both BMPR2 mutation and agonists to the serotonin receptor HTR2B have been shown to cause activation of SRC tyrosine kinase; conversely, antagonists to HTR2B inhibit SRC trafficking and downstream function. To test the hypothesis that a HTR2B antagonist can prevent BMRP2 mutation induced PAH by restricting aberrant SRC trafficking and downstream activity, we exposed BMPR2 mutant mice, which spontaneously develop PAH, to a HTR2B antagonist, SB204741, to block the SRC activation caused by BMPR2 mutation. SB204741 prevented the development of PAH in BMPR2 mutant mice, reduced recruitment of inflammatory cells to their lungs, and reduced muscularization of their blood vessels. By atomic force microscopy, we determined that BMPR2 mutant mice normally had a doubling of vessel stiffness, which was substantially normalized by HTR2B inhibition. SB204741 reduced SRC phosphorylation and downstream activity in BMPR2 mutant mice. Gene expression arrays indicate that the primary changes were in cytoskeletal and muscle contractility genes. These results were confirmed by gel contraction assays showing that HTR2B inhibition nearly normalizes the 400% increase in gel contraction normally seen in BMPR2 mutant smooth muscle cells. Heritable PAH results from increased SRC activation, cellular contraction, and vascular resistance, but antagonism of HTR2B prevents SRC phosphorylation, downstream activity, and PAH in BMPR2 mutant mice. PMID:26863209
Fok, E.; Guildford, A. L.
Corneal limbal stem cell deficiency (LSCD) may be treated using ex vivo limbal epithelial stem cells (LESCs) derived from cadaveric donor tissue. However, continuing challenges exist around tissue availability, inflammation, and transplant rejection. Lipopolysaccharide (LPS) or recombinant human IL-1β stimulated primary human keratocyte and LESC models were used to investigate the anti-inflammatory properties of a short chain, IL-1 receptor antagonist peptide for use in LESC sheet growth to control inflammation. The peptide was characterized using mass spectroscopy and high performance liquid chromatography. Peptide cytotoxicity, patterns of cell cytokine expression in response to LPS or IL-1β stimulation, and peptide suppression of this response were investigated by MTS/LDH assays, ELISA, and q-PCR. Cell differences in LPS stimulated toll-like receptor 4 expression were investigated using immunocytochemistry. A significant reduction in rIL-1β stimulated inflammatory cytokine production occurred following LESC and keratocyte incubation with anti-inflammatory peptide and in LPS stimulated IL-6 and IL-8 production following keratocyte incubation with peptide (1 mg/mL) (P < 0.05). LESCs produced no cytokine response to LPS stimulation and showed no TLR4 expression. The peptide supported LESC growth when adhered to a silicone hydrogel contact lens indicating potential use in improved LESC grafting through suppression of inflammation. PMID:25705668
Towne, Jennifer E; Garka, Kirsten E; Renshaw, Blair R; Virca, G Duke; Sims, John E
Interleukin 1 (IL-1) plays a prominent role in immune and inflammatory reactions. Our understanding of the IL-1 family has recently expanded to include six novel members named IL-1F5 to IL-1F10. Recently, it was reported that IL-1F9 activated NF-kappaB through the orphan receptor IL-1 receptor (IL-1R)-related protein 2 (IL-1Rrp2) in Jurkat cells (Debets, R., Timans, J. C., Homey, B., Zurawski, S., Sana, T. R., Lo, S., Wagner, J., Edwards, G., Clifford, T., Menon, S., Bazan, J. F., and Kastelein, R. A. (2001) J. Immunol. 167, 1440-1446). In this study, we demonstrate that IL-1F6 and IL-1F8, in addition to IL-1F9, activate the pathway leading to NF-kappaB in an IL-1Rrp2-dependent manner in Jurkat cells as well as in multiple other human and mouse cell lines. Activation of the pathway leading to NF-kappaB by IL-1F6 and IL-1F8 follows a similar time course to activation by IL-1beta, suggesting that signaling by the novel family members occurs through a direct mechanism. In a mammary epithelial cell line, NCI/ADR-RES, which naturally expresses IL-1Rrp2, all three cytokines signal without further receptor transfection. IL-1Rrp2 antibodies block activation of the pathway leading to NF-kappaB by IL-1F6, IL-1F8, and IL-1F9 in both Jurkat and NCI/ADR-RES cells. In NCI/ADR-RES cells, the three IL-1 homologs activated the MAPKs, JNK and ERK1/2, and activated downstream targets as well, including an IL-8 promoter reporter and the secretion of IL-6. We also provide evidence that IL-1RAcP, in addition to IL-1Rrp2, is required for signaling by all three cytokines. Antibodies directed against IL-1RAcP and transfection of cytoplasmically deleted IL-1RAcP both blocked activation of the pathway leading to NF-kappaB by the three cytokines. We conclude that IL-1F6, IL-1F8, and IL-1F9 signal through IL-1Rrp2 and IL-1RAcP.
Souza, PPC; Brechter, AB; Reis, RI; Costa, CAS; Lundberg, P; Lerner, UH
Background and Purpose Bone resorption induced by interleukin-1β (IL-1β) and tumour necrosis factor (TNF-α) is synergistically potentiated by kinins, partially due to enhanced kinin receptor expression. Inflammation-induced bone resorption can be impaired by IL-4 and IL-13. The aim was to investigate if expression of B1 and B2 kinin receptors can be affected by IL-4 and IL-13. Experimental Approach We examined effects in a human osteoblastic cell line (MG-63), primary human gingival fibroblasts and mouse bones by IL-4 and IL-13 on mRNA and protein expression of the B1 and B2 kinin receptors. We also examined the role of STAT6 by RNA interference and using Stat6-/- mice. Key Results IL-4 and IL-13 decreased the mRNA expression of B1 and B2 kinin receptors induced by either IL-1β or TNF-α in MG-63 cells, intact mouse calvarial bones or primary human gingival fibroblasts. The burst of intracellular calcium induced by either bradykinin (B2 agonist) or des-Arg10-Lys-bradykinin (B1 agonist) in gingival fibroblasts pretreated with IL-1β was impaired by IL-4. Similarly, the increased binding of B1 and B2 ligands induced by IL-1β was decreased by IL-4. In calvarial bones from Stat6-deficient mice, and in fibroblasts in which STAT6 was knocked down by siRNA, the effect of IL-4 was decreased. Conclusions and Implications These data show, for the first time, that IL-4 and IL-13 decrease kinin receptors in a STAT6-dependent mechanism, which can be one important mechanism by which these cytokines exert their anti-inflammatory effects and impair bone resorption. PMID:23351078
Kam, Wendy R.; Liu, Yang; Ding, Juan; Sullivan, David A.
Purpose Researchers have hypothesized that treatment with cyclosporine A (CyA), interleukin-1 receptor antagonists (IL-1RA; e.g., anakinra), P2Y2 receptor agonists (e.g., uridine triphosphate; UTP), and rebamipide may alleviate human meibomian gland dysfunction (MGD) and/or dry eye disease. Investigators have also proposed that prostaglandin analogues (e.g., bimatoprost) may induce MGD. Our goal was to determine whether these compounds directly influence human meibomian gland epithelial cell (HMGEC) function. Methods Multiple concentrations of each compound were tested for effects on immortalized (I) HMGEC morphology and survival. Nontoxic dosages were used for our studies. Immortalized HMGEC were cultured in the presence of vehicle, CyA, IL-1RA, UTP, rebamipide, or bimatoprost for up to 6 days in various media. Experiments included positive controls for proliferation (epidermal growth factor and bovine pituitary extract), differentiation (azithromycin), and signaling pathway activation (insulin-like growth factor 1). Cells were analyzed for neutral lipid staining, lysosome accumulation, lipid composition, and phosphatidylinositol-3-kinase/Akt (AKT), phosphorylation. Results Our findings demonstrate that CyA, IL-1RA, UTP, rebamipide, and bimatoprost had no effect on the proliferation; neutral lipid content; lysosome number; or levels of free cholesterol, triglycerides, or phospholipids in IHMGECs. Cylosporine A, IL-1RA, rebamipide, and bimatoprost significantly reduced the phosphorylation of AKT, as compared to control. Of interest, tested doses of CyA above 8 nM killed the IHMGECs. Conclusions Our results show that CyA, IL-1RA, UTP, rebamipide, and bimatoprost do not influence the proliferation or differentiation of IHMGEC. However, with the exception of UTP, these compounds do decrease the activity of the AKT signaling pathway, which is known to promote cell survival. PMID:27552406
Kam, Wendy R; Liu, Yang; Ding, Juan; Sullivan, David A
Researchers have hypothesized that treatment with cyclosporine A (CyA), interleukin-1 receptor antagonists (IL-1RA; e.g., anakinra), P2Y2 receptor agonists (e.g., uridine triphosphate; UTP), and rebamipide may alleviate human meibomian gland dysfunction (MGD) and/or dry eye disease. Investigators have also proposed that prostaglandin analogues (e.g., bimatoprost) may induce MGD. Our goal was to determine whether these compounds directly influence human meibomian gland epithelial cell (HMGEC) function. Multiple concentrations of each compound were tested for effects on immortalized (I) HMGEC morphology and survival. Nontoxic dosages were used for our studies. Immortalized HMGEC were cultured in the presence of vehicle, CyA, IL-1RA, UTP, rebamipide, or bimatoprost for up to 6 days in various media. Experiments included positive controls for proliferation (epidermal growth factor and bovine pituitary extract), differentiation (azithromycin), and signaling pathway activation (insulin-like growth factor 1). Cells were analyzed for neutral lipid staining, lysosome accumulation, lipid composition, and phosphatidylinositol-3-kinase/Akt (AKT), phosphorylation. Our findings demonstrate that CyA, IL-1RA, UTP, rebamipide, and bimatoprost had no effect on the proliferation; neutral lipid content; lysosome number; or levels of free cholesterol, triglycerides, or phospholipids in IHMGECs. Cylosporine A, IL-1RA, rebamipide, and bimatoprost significantly reduced the phosphorylation of AKT, as compared to control. Of interest, tested doses of CyA above 8 nM killed the IHMGECs. Our results show that CyA, IL-1RA, UTP, rebamipide, and bimatoprost do not influence the proliferation or differentiation of IHMGEC. However, with the exception of UTP, these compounds do decrease the activity of the AKT signaling pathway, which is known to promote cell survival.
Peterson, Troy S.; Thebeau, Christina N.; Ajit, Deepa; Camden, Jean M.; Woods, Lucas T.; Wood, W. Gibson; Petris, Michael J; Sun, Grace Y.; Erb, Laurie; Weisman, Gary A.
The proinflammatory cytokine interleukin-1β (IL-1β), whose levels are elevated in the brain in Alzheimer’s and other neurodegenerative diseases, has been shown to have both detrimental and beneficial effects on disease progression. In this paper, we demonstrate that incubation of mouse primary cortical neurons (mPCNs) with IL-1β increases the expression of the P2Y2 nucleotide receptor (P2Y2R) and that activation of the upregulated receptor with UTP, a relatively selective agonist of the P2Y2R, increases neurite outgrowth. Consistent with the accepted role of cofilin in the regulation of neurite extension, results indicate that incubation of IL-1β-treated mPCNs with UTP increases the phosphorylation of cofilin, a response absent in PCNs isolated from P2Y2R−/− mice. Other findings indicate that function blocking anti-αvβ3/5 integrin antibodies prevent UTP-induced cofilin activation in IL-1β-treated mPCNs, suggesting that established P2Y2R/αvβ3/5 interactions that promote G12-dependent Rho activation lead to cofilin phosphorylation involved in neurite extension. Cofilin phosphorylation induced by UTP in IL-1β-treated mPCNs is also decreased by inhibitors of Ca2+/calmodulin-dependent protein kinase II (CaMKII), suggesting a role for P2Y2R-mediated and Gq-dependent calcium mobilization in neurite outgrowth. Taken together, these studies indicate that upregulation of P2Y2Rs in mPCNs under proinflammatory conditions can promote cofilin-dependent neurite outgrowth, a neuroprotective response that may be a novel pharmacological target in the treatment of neurodegenerative diseases. PMID:23550835
Peterson, Troy S; Thebeau, Christina N; Ajit, Deepa; Camden, Jean M; Woods, Lucas T; Wood, W Gibson; Petris, Michael J; Sun, Grace Y; Erb, Laurie; Weisman, Gary A
The pro-inflammatory cytokine interleukin-1β (IL-1β), whose levels are elevated in the brain in Alzheimer's and other neurodegenerative diseases, has been shown to have both detrimental and beneficial effects on disease progression. In this article, we demonstrate that incubation of mouse primary cortical neurons (mPCNs) with IL-1β increases the expression of the P2Y2 nucleotide receptor (P2Y2R) and that activation of the up-regulated receptor with UTP, a relatively selective agonist of the P2Y2R, increases neurite outgrowth. Consistent with the accepted role of cofilin in the regulation of neurite extension, results indicate that incubation of IL-1β-treated mPCNs with UTP increases the phosphorylation of cofilin, a response absent in PCNs isolated from P2Y2R(-/-) mice. Other findings indicate that function-blocking anti-αv β3/5 integrin antibodies prevent UTP-induced cofilin activation in IL-1β-treated mPCNs, suggesting that established P2Y2R/αv β3/5 interactions that promote G12 -dependent Rho activation lead to cofilin phosphorylation involved in neurite extension. Cofilin phosphorylation induced by UTP in IL-1β-treated mPCNs is also decreased by inhibitors of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII), suggesting a role for P2Y2R-mediated and Gq-dependent calcium mobilization in neurite outgrowth. Taken together, these studies indicate that up-regulation of P2Y2Rs in mPCNs under pro-inflammatory conditions can promote cofilin-dependent neurite outgrowth, a neuroprotective response that may be a novel pharmacological target in the treatment of neurodegenerative diseases. © 2013 International Society for Neurochemistry.
Eun, So Young; Ko, Young Shin; Park, Sang Won; Chang, Ki Churl; Kim, Hye Jung
Vascular smooth muscle cells (VSMCs) are the major cell type in blood vessel walls, and their proliferation and migration play important roles in the development of atherosclerosis. Recently, it has been reported that IL-1β mediates the inflammatory response through the upregulation of the P2Y2 receptor (P2Y2R). Thus, we examined the role of P2Y2R in IL-1β-mediated proliferation and migration of VSMCs and the underlying molecular mechanisms. VSMCs were pretreated with IL-1β for 24h to upregulate P2Y2R expression. The cells were then stimulated with UTP or ATP for the indicated times, and cell proliferation and migration and the related signaling pathways were examined. The equipotent P2Y2R agonists ATP and UTP enhanced proliferation, RAGE expression and HMGB1 secretion in IL-1β-pretreated VSMCs. Additionally, pretreatment with IL-1β enhanced UTP-mediated VSMC migration and MMP-2 release, but these effects were not observed in the P2Y2R-siRNA- or RAGE-siRNA-transfected VSMCs. Next, the signaling molecules involved in P2Y2R-mediated cell proliferation and migration were determined. The ERK, AKT, PKC, Rac-1 and ROCK2 pathways were involved in UTP-induced cell proliferation and migration, MMP-2 and HMGB1 secretion and RAGE expression in the IL-1β-pretreated VSMCs. UTP induced the phosphorylation of ERK, AKT and PKC and the translocation of Rac-1 and ROCK2 from cytosol to membrane as well as stress fiber formation, which were markedly increased in the IL-1β-pretreated VSMCs but not in the P2Y2R-siRNA-transfected VSMCs. These results demonstrate that pro-inflammatory cytokines associated with atherosclerosis, such as IL-1β, can accelerate the process of atherosclerosis through the upregulation of P2Y2R. Copyright © 2015 Elsevier Inc. All rights reserved.
Costelloe, Ceire; Watson, Melanie; Murphy, Aine; McQuillan, Keith; Loscher, Christine; Armstrong, Michelle E; Garlanda, Cecilia; Mantovani, Alberto; O'Neill, Luke A J; Mills, Kingston H G; Lynch, Marina A
Similarity in structure and sequence homology has led to the identification of new members of the interleukin-1 (IL-1) ligand and receptor superfamilies. IL-1F6, IL-1F8 and IL-1F9 have been shown to signal through IL-1R-related protein 2 and IL-1 receptor accessory protein leading to activation of NFkappaB, while IL-1F7 and IL-1F10 interact with the IL-18 receptor and the soluble IL-1 receptor type I respectively. In contrast, identification of a biological role for IL-1F5 has remained elusive, with conflicting data relating to its possible ability to antagonize IL-1F9-stimulated activation of NFkappaB in Jurkat cells transfected with IL-1R-related protein 2. In this study, we set out to investigate a possible role for IL-1F5 in the brain and report that it antagonizes the inflammatory effects of IL-1beta and lipopolysaccharide (LPS) in vivo and in vitro including the inhibitory effect on long-term potentiation (LTP) in rat hippocampus. We demonstrate that IL-1F5 induces IL-4 mRNA and protein expression in glia in vitro and enhances hippocampal expression of IL-4 following intracerebroventricular (i.c.v.) injection. The inhibitory effect of IL-1F5 on LPS-induced IL-1beta is attenuated in cells from IL-4-defective (IL-4-/- mice). Our findings suggest that IL-1F5 mediates anti-inflammatory effects through its ability to induce IL-4 production and that this is a consequence of its interaction with the orphan receptor, single Ig IL-1R-related molecule (SIGIRR)/TIR8, as the effects were not observed in SIGIRR-/- mice. In contrast to its effects in brain tissue, IL-1F5 did not attenuate LPS-induced changes, or up-regulated IL-4 in macrophages or dendritic cells, suggesting that the effect is confined to the brain.
Salgado, Rosa M; Alcántara, Luz; Mendoza-Rodríguez, C Adriana; Cerbón, Marco; Hidalgo-González, Christian; Mercadillo, Patricia; Moreno, Luis M; Alvarez-Jiménez, Ricardo; Krötzsch, Edgar
Post-burn hypertrophic scars are characterized by increased collagen synthesis and hyperplasia, and may be associated with erythema, pain, dysesthesia, pruritus, and skin border elevation. Although the etiopathogenesis of hypertrophic scarring remains unclear, proinflammatory and profibrogenic cytokines are known to play an important role in general skin dysfunction. This study assessed mRNA expression, proteins, and type I receptors of tumor necrosis factor-alpha (TNF-α) and interleukin 1-beta (IL-1β) in normal skin, normotrophic and post-burn hypertrophic scars. Skin biopsies were obtained from 10 hypertrophic and 9 normotrophic scars, and 4 normal skin sites. Only post-burn scars covering more than 10% of the body were included. Ex vivo histopathological analysis evaluated scar maturity, in situ hybridization assessed mRNA expression, and cytokine protein and cytokine/cell colocalization were performed using single- and double-label immunohistochemistry, respectively. IL-1β is overexpressed in hypertrophic scars at the post-transcriptional level, associated primarily with keratinocytes and CD1a(+) cells. Type I receptors for TNF-α are overexpressed in blood vessels of hypertrophic scars. The coordinated overexpression of IL-1β and TNF-α type I receptor may maintain the fibrogenic phenotypes of hypertrophic scars, even those in "remission". Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.
Wang, Haibin; Gao, Minghui; Wang, Junjian
Kaempferol is a dietary flavonoid that can function as a selective estrogen receptor modulator (SERM). Estrogen-related receptors alpha and gamma (ERRα and ERRγ) are orphan nuclear receptors that play important roles in mitochondrial biogenesis and cancer development. We have shown that kaempferol can functionally antagonize the activities of ERRs based on both response element reporter systems and target gene analysis. Kaempferol modulation of mitochondrial function and suppression cancer cell growth has been confirmed. These findings suggest that kaempferol may exert their anti-cancer activities through antagonizing ERRs activities.
Kovalchin, Joseph; King, Bracken; Masci, Allyson; Hopkins, Elizabeth; Fry, Jeremy; Hou, Jay; Li, Christian; Tenneson, Kelly; Weber, Steve; Wolfe, Gary; Collins, Kathy; Furfine, Eric S
Topical interleukin (IL)-1 receptor (R)1 blockade is therapeutically active in reducing signs and symptoms of dry eye disease. Herein, we describe in vitro and in vivo nonclinical Investigational New Drug (IND)-enabling studies of EBI-005, a novel protein chimera of IL-1β and IL-1 receptor antagonist (IL-1Ra or anakinra) that potently binds IL-1R1 and blocks signaling. These studies provide an assessment of receptor affinity, drug bioavailability, immunogenic response, safety, and tolerability in mice and rabbits. In vitro and in silico along with Good Laboratory Practices (GLP) and non-GLP in vivo studies in mice and rabbits assessed the topical ocular and systemic immunogenicity and toxicology of EBI-005. Animals were treated with EBI-005 once daily subcutaneously or four times daily by topical ocular administration for up to 6 weeks (with 2-week recovery phase). EBI-005 has 500 times higher affinity than anakinra to IL-1R1. Predictive immunogenicity testing suggested that EBI-005 is not more immunogenic. Systemic bioavailability of EBI-005 is low (1.4% in mice and 0.2% in rabbits) after topical ocular administration. EBI-005 penetrated into the anterior ocular tissues within 15 min of topical ocular administration. However, it is low or undetectable after 4 hr and does not form a depot after repeated topical ocular administration. EBI-005 was safe and well tolerated, and exposure to drug was maintained despite an antidrug antibody response after systemic administration, based on IND-enabling toxicology and safety pharmacology studies. Ocular doses of EBI-005 at 50 mg/mL in mice and rabbits totaling 0.15 mg/eye in mice and 1.5 mg/eye in rabbits, administered 4 times daily, did not produce adverse effects, and demonstrated excellent bioavailability in target tissues with low systemic exposure. In addition, immunogenic response to the drug did not cause adverse effects or diminish the drug's activity in most cases. The results support drug administration of the
Rydman, Elina M; Ilves, Marit; Vanhala, Esa; Vippola, Minnamari; Lehto, Maili; Kinaret, Pia A S; Pylkkänen, Lea; Happo, Mikko; Hirvonen, Maija-Riitta; Greco, Dario; Savolainen, Kai; Wolff, Henrik; Alenius, Harri
Carbon nanotubes (CNT) have been eagerly studied because of their multiple applications in product development and potential risks on health. We investigated the difference of two different CNT and asbestos in inducing proinflammatory reactions in C57BL/6 mice after single pharyngeal aspiration exposure. We used long tangled and long rod-like CNT, as well as crocidolite asbestos at a dose of 10 or 40 µg/mouse. The mice were sacrificed 4 and 16 h or 7, 14, and 28 days after the exposure. To find out the importance of a major inflammatory marker IL-1β in CNT-induced pulmonary inflammation, we used etanercept and anakinra as antagonists as well as Interleukin 1 (IL-1) receptor (IL-1R-/-) mice. The results showed that rod-like CNT, and asbestos in lesser extent, induced strong pulmonary neutrophilia accompanied by the proinflammatory cytokines and chemokines 16 h after the exposure. Seven days after the exposure, neutrophilia had essentially disappeared but strong pulmonary eosinophilia peaked in rod-like CNT and asbestos-exposed groups. After 28 days, pulmonary granulomas, goblet cell hyperplasia, and Charcot-Leyden-like crystals containing acidophilic macrophages were observed especially in rod-like CNT-exposed mice. IL-1R-/- mice and antagonists-treated mice exhibited a significant decrease in neutrophilia and messenger ribonucleic acid (mRNA) levels of proinflammatory cytokines at 16 h. However, rod-like CNT-induced Th2-type inflammation evidenced by the expression of IL-13 and mucus production was unaffected in IL-1R-/- mice at 28 days. This study provides knowledge about the pulmonary effects induced by a single exposure to the CNT and contributes to hazard assessment of carbon nanomaterials on airway exposure. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: firstname.lastname@example.org.
Khan, Mohammed A.; Sham, Ho Pan; Bergstrom, Kirk; Huang, Jingtian T.; Steiner, Theodore S.; Assi, Kiran; Salh, Bill; Tai, Isabella T.; Li, Xiaoxia; Vallance, Bruce A.
Intestinal epithelial cells (IEC) are constantly exposed to enteric microbes. Although IECs express TLRs that recognize bacterial products, activation of these TLRs is strictly controlled through poorly understood mechanisms, producing a state of hypo-responsiveness and preventing unwanted inflammation. The Single IgG IL-1 related receptor (Sigirr) is a negative regulator of TLRs that is expressed by IEC and recently shown to inhibit experimental colitis. However, the importance of Sigirr in IEC hyporesponsiveness and its distribution within the human colon is unknown. In this study, we investigated the role of Sigirr in regulating epithelial specific TLR responses and characterize its expression in colonic biopsies. Transformed and non-transformed human IEC were cultured as monolayers. Transient gene silencing and stable over-expression of Sigirr was performed to assess innate IEC responses. Sigirr expression in human colonic biopsies was examined by immunohistochemistry. Bacterial infection of IEC and exposure to flagellin transiently decreased Sigirr protein expression, concurrent with secretion of the neutrophil chemokine IL-8. Sigirr gene silencing augmented chemokine responses to bacterial flagellin, Pam3Cys and the cytokine IL-1β. Conversely, stable over-expression of Sigirr diminished NF-κB mediated IL-8 responses to TLR ligands. We also found that Sigirr expression increased as IECs differentiated in culture. This observation was confirmed in biopsy sections, where Sigirr expression within colonic crypts was prominent in IECs at the apex and diminished at the base. Our findings show that Sigirr broadly regulates innate responses in differentiated human IEC, and may therefore modulate epithelial involvement in infectious and inflammatory bowel diseases. PMID:20130217
Kidney injury implies danger signaling and a response by the immune system. The inflammasome is a central danger recognition platform that triggers local and systemic inflammation. In immune cells, inflammasome activation causes the release of mature IL-1β and of the alarmin IL-1α Dying cells release IL-1α also, independently of the inflammasome. Both IL-1α and IL-1β ligate the same IL-1 receptor (IL-1R) that is present on nearly all cells inside and outside the kidney, further amplifying cytokine and chemokine release. Thus, the inflammasome-IL-1α/IL-β-IL-1R system is a central element of kidney inflammation and the systemic consequences. Seminal discoveries of recent years have expanded this central paradigm of inflammation. This review gives an overview of arising concepts of inflammasome and IL-1α/β regulation in renal cells and in experimental kidney disease models. There is a pipeline of compounds that can interfere with the inflammasome-IL-1α/IL-β-IL-1R system, ranging from recently described small molecule inhibitors of NLRP3, a component of the inflammasome complex, to regulatory agency-approved IL-1-neutralizing biologic drugs. Based on strong theoretic and experimental rationale, the potential therapeutic benefits of using such compounds to block the inflammasome-IL-1α/IL-β-IL-1R system in kidney disease should be further explored.
Palmer, Gaby; Lipsky, Brian P; Smithgall, Molly D; Meininger, David; Siu, Sophia; Talabot-Ayer, Dominique; Gabay, Cem; Smith, Dirk E
Interleukin (IL)-33 (or IL-1F11) was recently identified as a ligand for the orphan IL-1 receptor family member T1/ST2 (ST2). IL-33 belongs to the IL-1 cytokine family and, upon binding to ST2, induces intracellular signals similar to those utilized by IL-1. The effects of other IL-1 family cytokines are mediated by their binding to a specific receptor and the recruitment of a co-receptor required for elicitation of signaling. The aim of this study was to characterize the co-receptor involved in IL-33 signaling. Immunoprecipitation confirmed that IL-33 specifically binds ST2 and revealed that cellular IL-1 receptor accessory protein (AcP) associates with ST2 in a ligand-dependent manner. Receptor binding measurements demonstrated that the affinity of mouse (m)IL-33 for ST2 is increased by 4-fold in presence of AcP. IL-33 dose-dependently stimulated IL-6 secretion from wild-type (WT) mast cells, while no effect of IL-33 was observed with mast cells derived from AcP-deficient mice. Finally, soluble (s)ST2-Fc and sAcP-Fc acted synergistically to inhibit IL-33 activity. These observations identify AcP as a shared co-receptor within the IL-1 family that is essential for IL-33 signaling and suggest a novel role for sAcP in modulating the activity of IL-33.
Chu, Jia-Qi; Shi, Ge; Fan, Yi-Ming; Choi, In-Wook; Cha, Guang-Ho; Zhou, Yu; Lee, Young-Ha; Quan, Juan-Hua
Toxoplasma gondii is an obligate intracellular parasite that stimulates production of high levels of proinflammatory cytokines, which are important for innate immunity. NLRs, i.e., nucleotide-binding oligomerization domain (NOD)-like receptors, play a crucial role as innate immune sensors and form multiprotein complexes called inflammasomes, which mediate caspase-1-dependent processing of pro-IL-1β. To elucidate the role of inflammasome components in T. gondii-infected THP-1 macrophages, we examined inflammasome-related gene expression and mechanisms of inflammasome-regulated cytokine IL-1β secretion. The results revealed a significant upregulation of IL-1β after T. gondii infection. T. gondii infection also upregulated the expression of inflammasome sensors, including NLRP1, NLRP3, NLRC4, NLRP6, NLRP8, NLRP13, AIM2, and NAIP, in a time-dependent manner. The infection also upregulated inflammasome adaptor protein ASC and caspase-1 mRNA levels. From this study, we newly found that T. gondii infection regulates NLRC4, NLRP6, NLRP8, NLRP13, AIM2, and neuronal apoptosis inhibitor protein (NAIP) gene expressions in THP-1 macrophages and that the role of the inflammasome-related genes may be critical for mediating the innate immune responses to T. gondii infection.
Chu, Jia-Qi; Shi, Ge; Fan, Yi-Ming; Choi, In-Wook; Cha, Guang-Ho; Zhou, Yu; Lee, Young-Ha; Quan, Juan-Hua
Toxoplasma gondii is an obligate intracellular parasite that stimulates production of high levels of proinflammatory cytokines, which are important for innate immunity. NLRs, i.e., nucleotide-binding oligomerization domain (NOD)-like receptors, play a crucial role as innate immune sensors and form multiprotein complexes called inflammasomes, which mediate caspase-1-dependent processing of pro-IL-1β. To elucidate the role of inflammasome components in T. gondii-infected THP-1 macrophages, we examined inflammasome-related gene expression and mechanisms of inflammasome-regulated cytokine IL-1β secretion. The results revealed a significant upregulation of IL-1β after T. gondii infection. T. gondii infection also upregulated the expression of inflammasome sensors, including NLRP1, NLRP3, NLRC4, NLRP6, NLRP8, NLRP13, AIM2, and NAIP, in a time-dependent manner. The infection also upregulated inflammasome adaptor protein ASC and caspase-1 mRNA levels. From this study, we newly found that T. gondii infection regulates NLRC4, NLRP6, NLRP8, NLRP13, AIM2, and neuronal apoptosis inhibitor protein (NAIP) gene expressions in THP-1 macrophages and that the role of the inflammasome-related genes may be critical for mediating the innate immune responses to T. gondii infection. PMID:28095655
Sarria, Benjamin; Naline, Emmanuel; Zhang, Yong; Cortijo, Julio; Molimard, Mathieu; Moreau, Joelle; Therond, Patrice; Advenier, Charles; Morcillo, Esteban J
The muscarinic functional antagonism of isoproterenol relaxation and the contribution of muscarinic M2 receptors were examined in human isolated bronchus. In intact tissues, acetylcholine (ACh) precontraction decreased isoproterenol potency and maximal relaxation (-log EC50 shift = -1.49 +/- 0.16 and E(max) inhibition for 100 microM ACh = 30%) more than the same levels of histamine contraction. The M2 receptor-selective antagonist methoctramine (1 microM) reduced this antagonism in ACh- but not histamine-contracted tissues. Similar results were obtained for forskolin-induced relaxation. After selective inactivation of M3 receptors with 4-diphenylacetoxy-N-(2-chloroethyl)piperadine hydrochloric acid (30 nM), demonstrated by abolition of contractile and inositol phosphate responses to ACh, muscarinic recontractile responses were obtained in U-46619-precontracted tissues fully relaxed with isoproterenol. Methoctramine antagonized recontraction, with pK(B) (6.9) higher than in intact tissues (5.4), suggesting participation of M2 receptors. In M3-inactivated tissues, methoctramine augmented the isoproterenol relaxant potency in U-46619-contracted bronchus and reversed the ACh-induced inhibition of isoproterenol cAMP accumulation. These results indicate that M2 receptors cause indirect contraction of human bronchus by reversing sympathetically mediated relaxation and contribute to cholinergic functional antagonism.
Akdis, Mübeccel; Aab, Alar; Altunbulakli, Can; Azkur, Kursat; Costa, Rita A; Crameri, Reto; Duan, Su; Eiwegger, Thomas; Eljaszewicz, Andrzej; Ferstl, Ruth; Frei, Remo; Garbani, Mattia; Globinska, Anna; Hess, Lena; Huitema, Carly; Kubo, Terufumi; Komlosi, Zsolt; Konieczna, Patricia; Kovacs, Nora; Kucuksezer, Umut C; Meyer, Norbert; Morita, Hideaki; Olzhausen, Judith; O'Mahony, Liam; Pezer, Marija; Prati, Moira; Rebane, Ana; Rhyner, Claudio; Rinaldi, Arturo; Sokolowska, Milena; Stanic, Barbara; Sugita, Kazunari; Treis, Angela; van de Veen, Willem; Wanke, Kerstin; Wawrzyniak, Marcin; Wawrzyniak, Paulina; Wirz, Oliver F; Zakzuk, Josefina Sierra; Akdis, Cezmi A
There have been extensive developments on cellular and molecular mechanisms of immune regulation in allergy, asthma, autoimmune diseases, tumor development, organ transplantation, and chronic infections during the last few years. Better understanding the functions, reciprocal regulation, and counterbalance of subsets of immune and inflammatory cells that interact through interleukins, interferons, TNF-α, and TGF-β offer opportunities for immune interventions and novel treatment modalities in the era of development of biological immune response modifiers particularly targeting these molecules or their receptors. More than 60 cytokines have been designated as interleukins since the initial discoveries of monocyte and lymphocyte interleukins (called IL-1 and IL-2, respectively). Studies of transgenic or gene-deficient mice with altered expression of these cytokines or their receptors and analyses of mutations and polymorphisms in human genes that encode these products have provided essential information about their functions. Here we review recent developments on IL-1 to IL-38, TNF-α, TGF-β, and interferons. We highlight recent advances during the last few years in this area and extensively discuss their cellular sources, targets, receptors, signaling pathways, and roles in immune regulation in patients with allergy and asthma and other inflammatory diseases. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Huang, Chiung-Kuei; Luo, Jie; Lai, Kuo-Pao; Wang, Ronghao; Pang, Haiyan; Chang, Eugene; Yan, Chen; Sparks, Janet; Lee, Soo Ok; Cho, Joshua; Chang, Chawnshang
Gender difference is a risk factor for abdominal aortic aneurism formation yet the reason for male predominance remains unclear. Androgen and the androgen receptor influence the male gender difference, indicating that androgen receptor signaling may affect abdominal aortic aneurism development. Using angiotensin II induced abdominal aortic aneurism in apolipoprotein E null mouse models (82.4% abdominal aortic aneurism incidence), we found that mice lacking androgen receptor failed to develop abdominal aortic aneurism and aorta had dramatically reduced macrophages infiltration and intact elastic fibers. These findings suggested that androgen receptor expression in endothelial cells, macrophages or smooth muscle cells might play a role in abdominal aortic aneurism development. Selective knockout of androgen receptor in each of these cell types further demonstrated that mice lacking androgen receptor in macrophages (20% abdominal aortic aneurism incidence) or smooth muscle cells (12.5% abdominal aortic aneurism incidence), but not in endothelial cells (71.4% abdominal aortic aneurism incidence) had suppressed abdominal aortic aneurism development. Mechanism dissection showed that androgen receptor functioned through modulation of interleukin 1α and transforming growth factor β1 signals and by targeting androgen receptor with androgen receptor degradation enhancer ASC-J9® led to significant suppression of abdominal aortic aneurism development. These results demonstrate the underlying mechanism by which androgen receptor influences abdominal aortic aneurism development through interleukin 1α and transforming growth factor β1, and provides a potential new therapy to suppress/prevent abdominal aortic aneurism by targeting androgen receptor with ASC-J9®. PMID:26324502
BRANNEN, K.C., J.M. ROGERS, and E.S. HUNTER, Curriculum in Toxicology, University of North Carolina, Chapel Hill, North Carolina, and Reproductive Toxicology Division, NHEERL, U.S. EPA, Research Triangle Park, North Carolina. Endothelin-A receptor antagonism in embryo culture: w...
BRANNEN, K.C., J.M. ROGERS, and E.S. HUNTER, Curriculum in Toxicology, University of North Carolina, Chapel Hill, North Carolina, and Reproductive Toxicology Division, NHEERL, U.S. EPA, Research Triangle Park, North Carolina. Endothelin-A receptor antagonism in embryo culture: w...
Humphreys, Neil E; Grencis, Richard K
IL-1 null mice are unable to expel the intestinal nematode Trichuris muris; whereas WT littermates exhibit sterile immunity. Intriguingly the essential signalling components IL-1R1 and IL-1R accessory protein (AcP) are dispensable for expulsion of this parasite. IL-1 is thus critical for CD4(+) Th2-mediated immunity to T. muris; however, this action is independent of the established IL-1 signalling receptor. We also present data demonstrating that both IL-1alpha and IL-1beta induce measurable effects on T. muris primed cells isolated from IL-1R1 or IL-1R AcP null mice. MLN cells from these mice restimulated with parasite antigen proliferated at a greater rate and produced more cytokines in response to exogenous IL-1. This ability to respond to IL-1 was restricted to these parasite-primed cells and importantly was not evident in cells from naïve gene null mice. These in vitro data are consistent with the observed ability of mice with compromised IL-1 signalling to expel the parasite, bolstering the premise that an alternative IL-1 signalling mechanism is accessible in the context of an intestinal helminth-driven Th2 immune response.
Kaitocephalin is the first discovered natural toxin with protective properties against excitotoxic death of cultured neurons induced by N-methyl-d-aspartate (NMDA) or α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)/kainic acid (kainate, KA) receptors. Nevertheless, the effects of kaitocephalin on the function of these receptors were unknown. In this work, we report some pharmacological properties of synthetic (−)-kaitocephalin on rat brain glutamate receptors expressed in Xenopus laevis oocytes and on the homomeric AMPA-type GluR3 and KA-type GluR6 receptors. Kaitocephalin was found to be a more potent antagonist of NMDA receptors (IC50 = 75 ± 9 nM) than of AMPA receptors from cerebral cortex (IC50 = 242 ± 37 nM) and from homomeric GluR3 subunits (IC50 = 502 ± 55 nM). Moreover, kaitocephalin is a weak antagonist of the KA-type receptor GluR6 (IC50 ∼ 100 μM) and of metabotropic (IC50 > 100 μM) glutamate receptors expressed by rat brain mRNA. PMID:20436943
Vilia, Maria Giovanna; Fonte, Eleonora; Veliz Rodriguez, Tania; Tocchetti, Marta; Ranghetti, Pamela; Scarfò, Lydia; Papakonstantinou, Nikos; Ntoufa, Stavroula; Stamatopoulos, Kostas; Ghia, Paolo; Muzio, Marta
Toll interleukin-1 receptor 8 (also known as TIR8, SIGIRR, or IL1R8) is a transmembrane receptor that inhibits inflammation. Accordingly, genetic inactivation of this protein exacerbates chronic inflammation and inflammation-associated tumors in mice. In particular, lack of TIR8 triggers leukemia progression in a mouse model of chronic lymphocytic leukemia (CLL), supporting its role as a novel tumor restrainer. The aim of this study was to measure the amount of TIR8 mRNA and protein in CLL cells, and to analyze its regulation of expression. Circulating leukemic cells expressed lower levels of TIR8 compared to normal B-lymphocytes. Treatment of CLL cells with Azacytidine restored higher levels of TIR8 suggesting that DNA methylation may be involved in modulating TIR8 expression, with implications for novel therapeutic strategies.
Morris, Olivia; McMahon, Adam; Boutin, Herve; Grigg, Julian; Prenant, Christian
[(18) F]Fluoroacetaldehyde is a biocompatible prosthetic group that has been implemented pre-clinically using a semi-automated remotely controlled system. Automation of radiosyntheses permits use of higher levels of [(18) F]fluoride whilst minimising radiochemist exposure and enhancing reproducibility. In order to achieve full-automation of [(18) F]fluoroacetaldehyde peptide radiolabelling, a customised GE Tracerlab FX-FN with fully programmed automated synthesis was developed. The automated synthesis of [(18) F]fluoroacetaldehyde is carried out using a commercially available precursor, with reproducible yields of 26% ± 3 (decay-corrected, n = 10) within 45 min. Fully automated radiolabelling of a protein, recombinant human interleukin-1 receptor antagonist (rhIL-1RA), with [(18) F]fluoroacetaldehyde was achieved within 2 h. Radiolabelling efficiency of rhIL-1RA with [(18) F]fluoroacetaldehyde was confirmed using HPLC and reached 20% ± 10 (n = 5). Overall RCY of [(18) F]rhIL-1RA was 5% ± 2 (decay-corrected, n = 5) within 2 h starting from 35 to 40 GBq of [(18) F]fluoride. Specific activity measurements of 8.11-13.5 GBq/µmol were attained (n = 5), a near three-fold improvement of those achieved using the semi-automated approach. The strategy can be applied to radiolabelling a range of peptides and proteins with [(18) F]fluoroacetaldehyde analogous to other aldehyde-bearing prosthetic groups, yet automation of the method provides reproducibility thereby aiding translation to Good Manufacturing Practice manufacture and the transformation from pre-clinical to clinical production.
Lim, Eng-Kiat; Mitchell, Paul J.; Brown, Najmeeyah; Drummond, Rebecca A.; Brown, Gordon D.; Kaye, Paul M.; Bowles, Dianna J.
It is now recognized that innate immunity to intestinal microflora plays a significant role in mediating immune health, and modulation of microbial sensing may underpin the impact of plant natural products in the diet or when used as nutraceuticals. In this context, we have examined five classes of plant-derived flavonoids (flavonols, flavones, flavanones, catechins, and cyanidin) for their ability to regulate cytokine release induced by the Toll-like receptor 2 (TLR2) agonist Pam3CSK4. We found that the flavonols selectively co-stimulated IL-1β secretion but had no impact on the secretion of IL-6. Importantly, this costimulation of TLR2-induced cytokine secretion was dependent on regiospecific methylation of the flavonol scaffold with a rank order of quercetin-3,4′-dimethylether > quercetin-3-methylether > casticin. The mechanism underpinning this costimulation did not involve enhanced inflammasome activation. In contrast, the methylated flavonols enhanced IL-1β gene expression through transcriptional regulation, involving mechanisms that operate downstream of the initial NF-κB and STAT1 activation events. These studies demonstrate an exquisite level of control of scaffold bioactivity by regiospecific methylation, with important implications for understanding how natural products affect innate immunity and for their development as novel immunomodulators for clinical use. PMID:23760261
Kong, Qiongman; Peterson, Troy S.; Baker, Olga; Stanley, Emily; Camden, Jean; Seye, Cheikh I.; Erb, Laurie; Simonyi, Agnes; Wood, W. Gibson; Sun, Grace Y.; Weisman, Gary A.
The heterologous expression and activation of the human P2Y2 nucleotide receptor (P2Y2R) in human 1321N1 astrocytoma cells stimulates α-secretase-dependent cleavage of the amyloid precursor protein (APP), causing extracellular release of the non-amyloidogenic protein sAPPα. To determine whether a similar response occurs in a neuronal cell, we analyzed whether P2Y2R-mediated production of sAPPα occurs in rat primary cortical neurons (rPCNs). In rPCNs, P2Y2R mRNA and receptor activity were virtually absent in quiescent cells, whereas overnight treatment with the pro-inflammatory cytokine interleukin-1β (IL-1β) upregulated both P2Y2R mRNA expression and receptor activity by four-fold. The upregulation of the P2Y2R was abrogated by pre-incubation with Bay 11-7085, an IκB-α phosphorylation inhibitor, which suggests that P2Y2R mRNA transcript levels are regulated through NF-κB signaling. Furthermore, the P2Y2R agonist UTP enhanced the release of sAPPα in rPCNs treated with IL-1β or transfected with P2Y2R cDNA. UTP-induced release of sAPPα from rPCNs was completely inhibited by pretreatment of the cells with the metalloproteinase inhibitor TAPI-2 or the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002, and was partially inhibited by the MAPK/ERK kinase (MEK) inhibitor U0126 and the protein kinase C (PKC) inhibitor GF109203. These data suggest that P2Y2R-mediated release of sAPPα from cortical neurons is directly dependent on ADAM10/17 and PI3K activity, whereas ERK1/2 and PI3K activity may indirectly regulate APP processing. These results demonstrate that elevated levels of pro-inflammatory cytokines associated with neurodegenerative diseases, such as IL-1β, can enhance non-amyloidogenic APP processing through upregulation of the P2Y2R in neurons. PMID:19317852
Kato, Akihiko S; Burris, Kevin D; Gardinier, Kevin M; Gernert, Douglas L; Porter, Warren J; Reel, Jon; Ding, Chunjin; Tu, Yuan; Schober, Douglas A; Lee, Matthew R; Heinz, Beverly A; Fitch, Thomas E; Gleason, Scott D; Catlow, John T; Yu, Hong; Fitzjohn, Stephen M; Pasqui, Francesca; Wang, He; Qian, Yuewei; Sher, Emanuele; Zwart, Ruud; Wafford, Keith A; Rasmussen, Kurt; Ornstein, Paul L; Isaac, John T R; Nisenbaum, Eric S; Bredt, David S; Witkin, Jeffrey M
Pharmacological manipulation of specific neural circuits to optimize therapeutic index is an unrealized goal in neurology and psychiatry. AMPA receptors are important for excitatory synaptic transmission, and their antagonists are antiepileptic. Although efficacious, AMPA-receptor antagonists, including perampanel (Fycompa), the only approved antagonist for epilepsy, induce dizziness and motor impairment. We hypothesized that blockade of forebrain AMPA receptors without blocking cerebellar AMPA receptors would be antiepileptic and devoid of motor impairment. Taking advantage of an AMPA receptor auxiliary protein, TARP γ-8, which is selectively expressed in the forebrain and modulates the pharmacological properties of AMPA receptors, we discovered that LY3130481 selectively antagonized recombinant and native AMPA receptors containing γ-8, but not γ-2 (cerebellum) or other TARP members. Two amino acid residues unique to γ-8 determined this selectivity. We also observed antagonism of AMPA receptors expressed in hippocampal, but not cerebellar, tissue from an patient with epilepsy. Corresponding to this selective activity, LY3130481 prevented multiple seizure types in rats and mice and without motor side effects. These findings demonstrate the first rationally discovered molecule targeting specific neural circuitries for therapeutic advantage.
Van Gaal, Luc
Over the past 15 years, research on the endogenous cannabinoid (CB) system-now usually referred to as the endocannabinoid system (ECS)-has identified the significant effects of the ECS on the regulation of food intake and lipid and glucose metabolism in animals and humans. Endocannabinoids are endogenous lipids capable of binding to endogenous CB1 and CB2 receptors. CB1 receptors are present in the hypothalamic nuclei, which are involved in the control of energy balance and body weight, and in the mesolimbic system, which mediates the motivation to consume palatable food, as well as in adipocytes, the gut, and the liver. In the recent Rimonabant in Obesity (RIO)-Europe study, treatment with the first CB1 receptor antagonist, rimonabant, led to sustained, clinically meaningful weight loss and a reduction in waist circumference. Patients treated with rimonabant also demonstrated statistically significant improvement in high-density lipoprotein cholesterol levels, triglyceride levels, and insulin resistance, as well as a reduced overall prevalence of metabolic syndrome. Results of this and other studies support the role of endocannabinoids in the development and maintenance of obesity. In addition, these findings suggest that CB1 receptor antagonists such as rimonabant may offer a potential new approach to managing obesity and associated cardiometabolic risk factors.
Jesus, Adriana A; Goldbach-Mansky, Raphaela
Monogenic autoinflammatory syndromes present with excessive systemic inflammation including fever, rashes, arthritis, and organ-specific inflammation and are caused by defects in single genes encoding proteins that regulate innate inflammatory pathways. Pathogenic variants in two interleukin-1 (IL-1)-regulating genes, NLRP3 and IL1RN, cause two severe and early-onset autoinflammatory syndromes, CAPS (cryopyrin associated periodic syndromes) and DIRA (deficiency of IL-1 receptor antagonist). The discovery of the mutations that cause CAPS and DIRA led to clinical and basic research that uncovered the key role of IL-1 in an extended spectrum of immune dysregulatory conditions. NLRP3 encodes cryopyrin, an intracellular "molecular sensor" that forms a multimolecular platform, the NLRP3 inflammasome, which links "danger recognition" to the activation of the proinflammatory cytokine IL-1β. The success and safety profile of drugs targeting IL -1 in the treatment of CAPS and DIRA have encouraged their wider use in other autoinflammatory syndromes including the classic hereditary periodic fever syndromes (familial Mediterranean fever, TNF receptor-associated periodic syndrome, and hyperimmunoglobulinemia D with periodic fever syndrome) and additional immune dysregulatory conditions that are not genetically well defined, including Still's, Behcet's, and Schnitzler diseases. The fact that the accumulation of metabolic substrates such as monosodium urate, ceramide, cholesterol, and glucose can trigger the NLRP3 inflammasome connects metabolic stress to IL-1β-mediated inflammation and provides a rationale for therapeutically targeting IL-1 in prevalent diseases such as gout, diabetes mellitus, and coronary artery disease.
Martinez, Renata M; Zarpelon, Ana C; Cardoso, Renato D R; Vicentini, Fabiana T M C; Georgetti, Sandra R; Baracat, Marcela M; Andrei, Cesar C; Moreira, Isabel C; Verri, Waldiceu A; Casagrande, Rubia
CONTEXT. Tephrosia toxicaria is currently known as Tephrosia sinapou (Buc'hoz) A. Chev. (Fabaceae) and is a source of compounds such as flavonoids that inhibit inflammatory pain. To investigate the analgesic effect and mechanisms of the ethyl acetate extract of T. sinapou in inflammatory pain in mice. Behavioral responses were evaluated using mechanical (1-24 h) and thermal hyperalgesia (0.5-5 h), writhing response (20 min) and rota-rod (1-5 h) tests. Neutrophil recruitment (myeloperoxidase activity), cytokines (tumor necrosis factor [TNF]α and interleukin [IL]-1β), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) serum levels were determined by colorimetric assays. Pharmacological treatments were opioid receptor antagonist (naloxone, 0.1-1 mg/kg) and control opioid (morphine, 5 mg/kg). Inflammatory stimuli were carrageenin (100 µg/paw), complete Freund's adjuvant (CFA, 10 µl/paw), prostaglandin E2 (PGE2, 100 ng/paw) and acetic acid (0.8%). The intraperitoneal pre-treatment with extract inhibited in a dose-dependent (30-300 mg/kg) dependent manner the mechanical hyperalgesia induced by carrageenin (up to 93% inhibition). The post-treatment (100 mg/kg) inhibited CFA-induced hyperalgesia (up to 63% inhibition). Naloxone (1 mg/kg) prevented the inhibitory effect of the extract over carrageenin-induced mechanical (100%) and thermal (100%) hyperalgesia, neutrophil recruitment (52%) and TNFα (63%) and IL-1β (98%) production, thermal threshold in naïve mice (99%), PGE2-induced mechanical hyperalgesia (88%) and acetic acid-induced writhing response (49%). There was no significant alteration in the rota-rod test, and AST and ALT serum levels by extract treatment. Discussion and conclusion. Tephrosia sinapou ethyl acetate extract reduces inflammatory pain by activating an opioid receptor-dependent mechanism.
Vande Griend, Joseph P; Anderson, Sarah L
To evaluate the literature regarding the use of histamine-1 (H(1)) receptor antagonists and to describe their role in the treatment of insomnia in adult patients, including the elderly. Literature was identified via PubMed and Medline through April 1, 2012, using the search terms insomnia and sleep, each individually combined with histamine antagonist, tricyclic antidepressant, trazodone, mirtazapine, doxepin, amitriptyline, nortriptyline, trimipramine, doxylamine, diphenhydramine, and antihistamine. Data included randomized double-blind trials that statistically evaluated H(1) receptor antagonist treatment in patients with insomnia compared with a placebo control or Food and Drug Administration-approved insomnia treatment. Trials selected evaluated sleep latency, wake after sleep onset, total sleep time, number of awakenings, and/or sleep efficiency in a subjective or objective manner. A total of 65 trials were evaluated, and 16 met inclusion criteria. With the exception of low-dose doxepin (Silenor-Somaxon), trials evaluating the clinical effectiveness of H(1) receptor antagonists show mixed results and are limited by sample size and generalizability. Large, randomized, appropriately controlled trials are lacking, making it difficult to define the safety and efficacy of these agents. In contrast, low-dose doxepin has been shown to provide consistent sleep benefit compared with placebo. Over-the-counter antihistamines may have a role for short-term insomnia treatment in younger adults, but tolerance develops rapidly. Mirtazapine should not be used solely for the treatment of insomnia. Sedating antidepressants can be considered after failure of first-line insomnia treatments. Patients taking these agents chronically should be evaluated for continued efficacy and potential harm. Low-dose doxepin may have a unique role in the treatment of insomnia in elderly patients given its tolerability, documented efficacy, and lack of important adverse effects.
Gotter, Anthony L.; Forman, Mark S.; Harrell, Charles M.; Stevens, Joanne; Svetnik, Vladimir; Yee, Ka Lai; Li, Xiaodong; Roecker, Anthony J.; Fox, Steven V.; Tannenbaum, Pamela L.; Garson, Susan L.; Lepeleire, Inge De; Calder, Nicole; Rosen, Laura; Struyk, Arie; Coleman, Paul J.; Herring, W. Joseph; Renger, John J.; Winrow, Christopher J.
Orexin neuropeptides regulate sleep/wake through orexin receptors (OX1R, OX2R); OX2R is the predominant mediator of arousal promotion. The potential for single OX2R antagonism to effectively promote sleep has yet to be demonstrated in humans. MK-1064 is an OX2R-single antagonist. Preclinically, MK-1064 promotes sleep and increases both rapid eye movement (REM) and non-REM (NREM) sleep in rats at OX2R occupancies higher than the range observed for dual orexin receptor antagonists. Similar to dual antagonists, MK-1064 increases NREM and REM sleep in dogs without inducing cataplexy. Two Phase I studies in healthy human subjects evaluated safety, tolerability, pharmacokinetics and sleep-promoting effects of MK-1064, and demonstrated dose-dependent increases in subjective somnolence (via Karolinska Sleepiness Scale and Visual Analogue Scale measures) and sleep (via polysomnography), including increased REM and NREM sleep. Thus, selective OX2R antagonism is sufficient to promote REM and NREM sleep across species, similarly to that seen with dual orexin receptor antagonism. PMID:27256922
Calcutt, Nigel A; Smith, Darrell R; Frizzi, Katie; Sabbir, Mohammad Golam; Chowdhury, Subir K Roy; Mixcoatl-Zecuatl, Teresa; Saleh, Ali; Muttalib, Nabeel; Van der Ploeg, Randy; Ochoa, Joseline; Gopaul, Allison; Tessler, Lori; Wess, Jürgen; Jolivalt, Corinne G; Fernyhough, Paul
Sensory neurons have the capacity to produce, release, and respond to acetylcholine (ACh), but the functional role of cholinergic systems in adult mammalian peripheral sensory nerves has not been established. Here, we have reported that neurite outgrowth from adult sensory neurons that were maintained under subsaturating neurotrophic factor conditions operates under cholinergic constraint that is mediated by muscarinic receptor-dependent regulation of mitochondrial function via AMPK. Sensory neurons from mice lacking the muscarinic ACh type 1 receptor (M1R) exhibited enhanced neurite outgrowth, confirming the role of M1R in tonic suppression of axonal plasticity. M1R-deficient mice made diabetic with streptozotocin were protected from physiological and structural indices of sensory neuropathy. Pharmacological blockade of M1R using specific or selective antagonists, pirenzepine, VU0255035, or muscarinic toxin 7 (MT7) activated AMPK and overcame diabetes-induced mitochondrial dysfunction in vitro and in vivo. These antimuscarinic drugs prevented or reversed indices of peripheral neuropathy, such as depletion of sensory nerve terminals, thermal hypoalgesia, and nerve conduction slowing in diverse rodent models of diabetes. Pirenzepine and MT7 also prevented peripheral neuropathy induced by the chemotherapeutic agents dichloroacetate and paclitaxel or HIV envelope protein gp120. As a variety of antimuscarinic drugs are approved for clinical use against other conditions, prompt translation of this therapeutic approach to clinical trials is feasible.
Seawell, Michael R.; Darazi, Fahed Al; Farah, Victor; Ramanathan, Kodangudi B.; Newman, Kevin P.; Bhattacharya, Syamal K.; Weber, Karl T.
The symptoms and signs constituting the congestive heart failure (CHF) syndrome have their pathophysiologic origins rooted in a salt-avid renal state mediated by effector hormones of the renin-angiotensin-aldosterone and adrenergic nervous systems. Controlled clinical trials, conducted over the past decade in patients having minimally to markedly severe symptomatic heart failure, have demonstrated the efficacy of a pharmacologic regimen that interferes with these hormones, including aldosterone receptor binding with either spironolactone or eplerenone. Potential pathophysiologic mechanisms which have not hitherto been considered involved for the salutary responses and cardioprotection provided by these mineralocorticoid receptor antagonists are reviewed herein. In particular, we focus on the less well-recognized impact of catecholamines and aldosterone on mono- and divalent cation dyshomeostasis which leads to hypokalemia, hypomagnesemia, ionized hypocalcemia with secondary hyperparathyroidism and hypozincemia. Attendant adverse cardiac consequences include a delay in myocardial repolarization with increased propensity for supra- and ventricular arrhythmias and compromised antioxidant defenses with increased susceptibility to nonischemic cardiomyocyte necrosis. PMID:23114591
Barrera-Chimal, Jonatan; André-Grégoire, Gwennan; Nguyen Dinh Cat, Aurelie; Lechner, Sebastian M; Cau, Jérôme; Prince, Sonia; Kolkhof, Peter; Loirand, Gervaise; Sauzeau, Vincent; Hauet, Thierry; Jaisser, Frédéric
AKI is a frequent complication in hospitalized patients. Unfortunately, there is no effective pharmacologic approach for treating or preventing AKI. In rodents, mineralocorticoid receptor (MR) antagonism prevents AKI induced by ischemia-reperfusion (IR). We investigated the specific role of vascular MR in mediating AKI induced by IR. We also assessed the protective effect of MR antagonism in IR-induced AKI in the Large White pig, a model of human AKI. In mice, MR deficiency in smooth muscle cells (SMCs) protected against kidney IR injury. MR blockade by the novel nonsteroidal MR antagonist, finerenone, or genetic deletion of MR in SMCs associated with weaker oxidative stress production. Moreover, ischemic kidneys had higher levels of Rac1-GTP, required for NADPH oxidase activation, than sham control kidneys, and genetic deletion of Rac1 in SMCs protected against AKI. Furthermore, genetic deletion of MR in SMCs blunted the production of Rac1-GTP after IR. Pharmacologic inhibition of MR also prevented AKI induced by IR in the Large White pig. Altogether, we show that MR antagonism, or deletion of the MR gene in SMCs, limited the renal injury induced by IR through effects on Rac1-mediated MR signaling. The benefits of MR antagonism in the pig provide a rational basis for future clinical trials assessing the benefits of this approach in patients with IR-mediated AKI.
Dagdas, Yasin F; Belhaj, Khaoula; Maqbool, Abbas; Chaparro-Garcia, Angela; Pandey, Pooja; Petre, Benjamin; Tabassum, Nadra; Cruz-Mireles, Neftaly; Hughes, Richard K; Sklenar, Jan; Win, Joe; Menke, Frank; Findlay, Kim; Banfield, Mark J; Kamoun, Sophien; Bozkurt, Tolga O
Plants use autophagy to safeguard against infectious diseases. However, how plant pathogens interfere with autophagy-related processes is unknown. Here, we show that PexRD54, an effector from the Irish potato famine pathogen Phytophthora infestans, binds host autophagy protein ATG8CL to stimulate autophagosome formation. PexRD54 depletes the autophagy cargo receptor Joka2 out of ATG8CL complexes and interferes with Joka2's positive effect on pathogen defense. Thus, a plant pathogen effector has evolved to antagonize a host autophagy cargo receptor to counteract host defenses. DOI: http://dx.doi.org/10.7554/eLife.10856.001 PMID:26765567
Edye, Michelle E; Brough, David; Allan, Stuart M
Noncommunicable diseases such as cardiovascular disease (stroke and heart attack), cancer, chronic respiratory disease, and diabetes are a leading cause of death and disability worldwide and are worsened by inflammation. IL-1 is a driver of inflammation and implicated in many noncommunicable diseases. Acidosis is also a key feature of the inflammatory microenvironment; therefore it is vital to explore IL-1 signaling under acidic conditions. A HEK-IL-1 reporter assay and brain endothelial cell line were used to explore activity of mature IL-1α and IL-1β at pH 7.4 and pH 6.2, an acidic pH that can be reached under inflammatory or ischemic conditions, alongside cathepsin D-cleaved 20-kDa IL-1β produced under acidic conditions. We report that mature IL-1 signaling at IL-1 receptor type 1 (IL-1R1) is maintained at pH 6.2, but the activity of the decoy receptor, IL-1R2, is reduced. Additionally, cathepsin D-cleaved 20-kDa IL-1β was minimally active at IL-1R1 and was not further cleaved to highly active 17-kDa IL-1β. Therefore formation of the 20-kDa form of IL-1β may prevent the generation of mature bioactive IL-1β and thus may limit inflammation. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.
Suen, J Y; Cotterell, A; Lohman, R J; Lim, J; Han, A; Yau, M K; Liu, L; Cooper, M A; Vesey, D A; Fairlie, D P
Background and Purpose Proteinase activated receptor 2 (PAR2) is a GPCR associated with inflammation, metabolism and disease. Clues to understanding how to block PAR2 signalling associated with disease without inhibiting PAR2 activation in normal physiology could be provided by studies of biased signalling. Experimental Approach PAR2 ligand GB88 was profiled for PAR2 agonist and antagonist properties by several functional assays associated with intracellular G-protein-coupled signalling in vitro in three cell types and with PAR2-induced rat paw oedema in vivo. Key Results In HT29 cells, GB88 was a PAR2 antagonist in terms of Ca2+ mobilization and PKC phosphorylation, but a PAR2 agonist in attenuating forskolin-induced cAMP accumulation, increasing ERK1/2 phosphorylation, RhoA activation, myosin phosphatase phosphorylation and actin filament rearrangement. In CHO-hPAR2 cells, GB88 inhibited Ca2+ release, but activated Gi/o and increased ERK1/2 phosphorylation. In human kidney tubule cells, GB88 inhibited cytokine secretion (IL6, IL8, GM-CSF, TNF-α) mediated by PAR2. A rat paw oedema induced by PAR2 agonists was also inhibited by orally administered GB88 and compared with effects of locally administered inhibitors of G-protein coupled pathways. Conclusions and Implications GB88 is a biased antagonist of PAR2 that selectively inhibits PAR2/Gq/11/Ca2+/PKC signalling, leading to anti-inflammatory activity in vivo, while being an agonist in activating three other PAR2-activated pathways (cAMP, ERK, Rho) in human cells. These findings highlight opportunities to design drugs to block specific PAR2-linked signalling pathways in disease, without blocking beneficial PAR2 signalling in normal physiology, and to dissect PAR2-associated mechanisms of disease in vivo. PMID:24821440
Azam, Faizul; Abugrain, Ismaiel Mohamed; Sanalla, Mohamed Hussin; Elnaas, Radwan Fatahalla; Rajab, Ibrahim Abdassalam Ibn
Glutamate receptors have been implicated in various neurological disorders and their antagonism offers a suitable approach for the treatment of such disorders. The field of drug design and discovery aims to find best medicines to prevent, treat and cure diseases quickly and efficiently. In this regard, computational tools have helped medicinal chemists modify and optimize molecules to potent drug candidates with better pharmacokinetic profiles, and guiding biologists and pharmacologists to explore new disease genes as well as novel drug targets. In the present study, to understand the structural requirements for AMPA receptor antagonism, molecular docking study was performed on 41 structurally diverse antagonists based on quinoxaline nucleus. Lamarckian genetic algorithm methodology was employed for docking simulations using AutoDock 4.2 program. The results obtained signify that the molecular docking approach is reliable and produces a good correlation coefficient (r2 = 0.6) between experimental and docking predicted AMPA receptor antagonistic activity. The aromatic moiety of quinoxaline core has been proved to be vital for hydrophobic contacts exhibiting - interactions in docked conformations. However, polar moieties such as carboxylic group and 1,2,4-triazole moieties were noted to be sites for hydrophilic interactions in terms of hydrogen bonding with the receptor. These analyses can be exploited to design and develop novel AMPA receptor antagonists for the treatment of different neurological disorders. PMID:24250113
Azam, Faizul; Abugrain, Ismaiel Mohamed; Sanalla, Mohamed Hussin; Elnaas, Radwan Fatahalla; Rajab, Ibrahim Abdassalam Ibn
Glutamate receptors have been implicated in various neurological disorders and their antagonism offers a suitable approach for the treatment of such disorders. The field of drug design and discovery aims to find best medicines to prevent, treat and cure diseases quickly and efficiently. In this regard, computational tools have helped medicinal chemists modify and optimize molecules to potent drug candidates with better pharmacokinetic profiles, and guiding biologists and pharmacologists to explore new disease genes as well as novel drug targets. In the present study, to understand the structural requirements for AMPA receptor antagonism, molecular docking study was performed on 41 structurally diverse antagonists based on quinoxaline nucleus. Lamarckian genetic algorithm methodology was employed for docking simulations using AutoDock 4.2 program. The results obtained signify that the molecular docking approach is reliable and produces a good correlation coefficient (r(2) = 0.6) between experimental and docking predicted AMPA receptor antagonistic activity. The aromatic moiety of quinoxaline core has been proved to be vital for hydrophobic contacts exhibiting - interactions in docked conformations. However, polar moieties such as carboxylic group and 1,2,4-triazole moieties were noted to be sites for hydrophilic interactions in terms of hydrogen bonding with the receptor. These analyses can be exploited to design and develop novel AMPA receptor antagonists for the treatment of different neurological disorders.
Preskorn, Sheldon H.; Victor, Teresa; Misaki, Masaya; Bodurka, Jerzy; Drevets, Wayne C.
Background: Acutely elevated cortisol levels in healthy humans impair autobiographical memory recall and alter hemodynamic responses of the amygdala to emotionally valenced stimuli. It is hypothesized that the effects of the cortisol on cognition are influenced by the ratio of mineralocorticoid receptor to glucocorticoid receptor occupation. The current study examined the effects of acutely blocking mineralocorticoid receptors and glucocorticoid receptors separately on 2 processes known to be affected by altering levels of cortisol: the specificity of autobiographical memory recall, and the amygdala hemodynamic response to sad and happy faces. Methods: We employed a within-subjects design in which 10 healthy male participants received placebo, the mineralocorticoid receptor antagonist spironolactone (600mg) alone, and the glucocorticoid receptor antagonist mifepristone (600mg) alone in a randomized, counter-balanced order separated by 1-week drug-free periods. Results: On autobiographical memory testing, mineralocorticoid receptor antagonism impaired, while glucocorticoid receptor antagonism improved, recall relative to placebo, as evinced by changes in the percent of specific memories recalled. During fMRI, the amygdala hemodynamic response to masked sad faces was greater under both mineralocorticoid receptor and glucocorticoid receptor antagonism relative to placebo, while the response to masked happy faces was attenuated only during mineralocorticoid receptor antagonism relative to placebo. Conclusions: These data suggest both mineralocorticoid receptor and glucocorticoid receptor antagonism (and potentially any deviation from the normal physiological mineralocorticoid receptor/glucocorticoid receptor ratio achieved under the circadian pattern) enhances amygdala-based processing of sad stimuli and may shift the emotional processing bias away from the normative processing bias and towards the negative valence. In contrast, autobiographical memory was enhanced by
Schepetkin, Igor A.; Khlebnikov, Andrei I.; Kirpotina, Liliya N.; Quinn, Mark T.
Formyl peptide receptor 1 (FPR1) regulates a wide variety of neutrophil functional responses and plays an important role in inflammation and the pathogenesis of various diseases. To date, a variety of natural and synthetic molecules have been identified as FPR1 ligands. Here, we review current knowledge on natural products and natural product-inspired small-molecules reported to antagonize and/or inhibit the FPR1-mediated responses. Based on this literature, additional screening of selected commercially available natural compounds for their ability to inhibit fMLF-induced Ca2+ mobilization in human neutrophils and FPR1 transfected HL-60 cells, and pharmacophore modeling, natural products with potential as FPR1 antagonists are considered and discussed in this review. The identification and characterization of natural products that antagonize FPR1 activity may have potential for the development of novel therapeutics to limit or alter the outcome of inflammatory processes. PMID:26382576
Schepetkin, Igor A; Khlebnikov, Andrei I; Kirpotina, Liliya N; Quinn, Mark T
Formyl peptide receptor 1 (FPR1) regulates a wide variety of neutrophil functional responses and plays an important role in inflammation and the pathogenesis of various diseases. To date, a variety of natural and synthetic molecules have been identified as FPR1 ligands. Here, we review current knowledge on natural products and natural product-inspired small molecules reported to antagonize and/or inhibit the FPR1-mediated responses. Based on this literature, additional screening of selected commercially available natural compounds for their ability to inhibit fMLF-induced Ca(2+) mobilization in human neutrophils and FPR1 transfected HL-60 cells, and pharmacophore modeling, natural products with potential as FPR1 antagonists are considered and discussed in this review. The identification and characterization of natural products that antagonize FPR1 activity may have potential for the development of novel therapeutics to limit or alter the outcome of inflammatory processes. Copyright © 2015 Elsevier B.V. All rights reserved.
Hedl, Matija; Abraham, Clara
Inflammatory diseases are characterized by dysregulated cytokine production. Altered functions for most risk loci, including the inflammatory bowel disease and leprosy-associated tumor necrosis factor ligand superfamily member 15 (TNFSF15) region, are unclear. Regulation of pattern-recognition-receptor (PRR)-induced signaling and cytokines is crucial for immune homeostasis; TNFSF15:death receptor 3 (DR3) contributions to PRR responses have not been described. We found that human macrophages expressed DR3 and that TNFSF15:DR3 interactions were critical for amplifying PRR-initiated MAPK/NF-κB/PI3K signaling and cytokine secretion in macrophages. Mechanisms mediating TNFSF15:DR3 contributions to PRR outcomes included TACE-induced TNFSF15 cleavage to soluble TNFSF15; soluble TNFSF15 then led to TRADD/FADD/MALT-1– and caspase-8–mediated autocrine IL-1 secretion. Notably, TNFSF15 treatment also induced cytokine secretion through a caspase-8–dependent pathway in intestinal myeloid cells. Importantly, rs6478108 A disease risk-carrier macrophages demonstrated increased TNFSF15 expression and PRR-induced signaling and cytokines. Taken together, TNFSF15:DR3 interactions amplify PRR-induced signaling and cytokines, and the rs6478108 TNFSF15 disease-risk polymorphism results in a gain of function. PMID:25197060
Prinssen, E P; Ellenbroek, B A; Cools, A R
Previous studies have shown that alpha 1-adrenoceptors, dopamine D1-like and 5-HT2A receptors play an important role in the effects of the atypical neuroleptic, clozapine, on the parameter modelling antipsychotic efficacy in the paw test. Therefore, it became of interest to investigate whether antagonism of all these receptors together would give rise to effects characteristic of clozapine. The effects of the combined administration of the alpha 1-adrenoceptor antagonist phenoxybenzamine, the dopamine D1 receptor antagonist, SCH 39166 (4-(4-chloro-3-methoxyphenyl)-1,2- dihydronaphthalene), and the 5-HT2A receptor antagonist, ketanserin, were therefore measured in the paw test. The present data show that all three drugs together, but not simply combinations of two out of three, produced a profile similar to that of clozapine: a significant increase in the parameter modelling antipsychotic efficacy and no change in the parameter modelling extrapyramidal side-effects.
Schrijver, Hans M; van As, Jaco; Crusius, J Bart A; Dijkstra, Christien D; Uitdehaag, Bernard M J
BACKGROUND: Multiple sclerosis (MS) is an autoimmune disorder, with a considerable genetic influence on susceptibility and disease course. Cytokines play an important role in MS pathophysiology, and genes encoding various cytokines are logical candidates to assess possible associations with MS susceptibility and disease course. We previously reported an association of a combination of polymorphisms in the interleukin (IL)-1B and IL-1 receptor antagonist (IL-1RN) genes (i.e. IL-1RN allele 2+/IL-1B(+3959)allele 2-) with disease severity in MS. Extending this observation, we investigated whether IL-1beta and IL-1ra production differed depending on carriership of this gene combination. METHODS: Twenty MS patients and 20 controls were selected based upon carriership of the specific combination. In whole blood, in vitro IL-1beta and IL-1ra production was determined by enzyme-linked immunosorbent-assay after 6 and 24 h of stimulation with lipopolysaccharide. RESULTS: Carriers of the specific combination produced more IL-1ra, especially in MS patients, although not significantly. IL-1ra production was significantly higher in individuals homozygous for IL-1RN allele 2. In patients, Il-1ra production was higher and IL-1beta production lower compared with controls. In primary progressive patients, the IL-1beta /IL-1ra ratio was significantly lower than in relapsing-remitting patients. CONCLUSION: Our results suggest higher in vitro IL-1ra production in carriers of IL-1RN allele 2, with an indication of an allelic dose-effect relationship. PMID:12775358
Sato, Takahiro; Nakashima, Yoshiki; Nakamura, Yuki; Ida, Takanori; Kojima, Masayasu
Ghrelin is a hormone that mediates a variety of physiological roles, such as stimulating appetite, initiating food intake, and modulating energy metabolism. Although it has been reported that a bolus injection of ghrelin decreases blood pressure, the effect of continuous ghrelin administration on vasoregulation has yet to be determined. We examined the longitudinal effect of ghrelin on vasoregulation using Dahl-Iwai salt-sensitive rats. In this model, a high-salt diet induced high blood pressure and increased ghrelin levels but reduced food intake. In salt-sensitive hypertension, cumulative food intake decreased, while both ghrelin messenger RNA levels and plasma ghrelin content increased. Continuous administration of a ghrelin receptor agonist, growth hormone releasing peptide-6 (GHRP-6), for 2 weeks by mini-osmotic pump did not change blood pressure values although the cumulative food intake recovered. In contrast, continuous administration of a ghrelin receptor antagonist, [D-Lys³]-GHRP-6, induced early elevations in blood pressure without changes in heart rate. Quantitative RT-PCR revealed high expression levels of genes involved in the catecholamine biosynthetic pathway, tyrosine hydroxylase and dopamine-β-hydroxylase, after continuous [D-Lys³]-GHRP-6 administration. These results indicate that continuous antagonism of the ghrelin receptor results in early induction of salt-sensitive hypertension in this animal model and suggests that increases in autonomic nervous activity induced by ghrelin receptor antagonism are responsible, as indicated by the high expression levels of genes in the catecholamine biosynthetic pathway.
Amin, D N; Goswami, S; Klein, T; Maayani, S; Marom, Z
A physiologic response such as mucin secretion from epithelial cells in vivo may be under the control of several endogenous substances such as acetylcholine, norepinephrine, and vasoactive intestinal peptide (VIP). These substances may simultaneously activate distinct membrane receptors that exist on the same epithelial cells, and this activation may result in reciprocal physiologic responses or functional antagonism. To test whether simultaneous activation of the VIP and muscarinic receptors or of beta-adrenoreceptors and muscarinic receptors affect mucin secretion in a reciprocal manner, we studied some characteristics of the resultant physiologic response in human epithelial cells secreting radiolabeled mucin-like glycoprotein (MLGP). Both basal and methacholine (M.chol)-induced MLGP secretion could be blocked by VIP (1 pM to 1 microM) and by isoproterenol (ISO) (0.1 nM to 10 nM) in a concentration-dependent and reversible manner. In a membrane preparation from the same cells, VIP (1 to 1,000 nM) and ISO (0.1 to 10 microM) stimulated adenylyl cyclase activity in a concentration-dependent and nonadditive manner. In the same membrane preparation, no effect of M.chol was observed on this response to VIP or to ISO. It is proposed that functional antagonism at the cellular level between basal or cholinergic-stimulated mucin secretion and either activated beta-adrenergic or VIP receptors may play a crucial role in modulation of mucin secretion from epithelial cells.
A Toll/interleukin (IL)-1 receptor domain protein from Yersinia pestis interacts with mammalian IL-1/Toll-like receptor pathways but does not play a central role in the virulence of Y. pestis in a mouse model of bubonic plague.
Spear, Abigail M; Rana, Rohini R; Jenner, Dominic C; Flick-Smith, Helen C; Oyston, Petra C F; Simpson, Peter; Matthews, Stephen J; Byrne, Bernadette; Atkins, Helen S
The Toll/interleukin (IL)-1 receptor (TIR) domain is an essential component of eukaryotic innate immune signalling pathways. Interaction between TIR domains present in Toll-like receptors and associated adaptors initiates and propagates an immune signalling cascade. Proteins containing TIR domains have also been discovered in bacteria. Studies have subsequently shown that these proteins are able to modulate mammalian immune signalling pathways dependent on TIR interactions and that this may represent an evasion strategy for bacterial pathogens. Here, we investigate a TIR domain protein from the highly virulent bacterium Yersinia pestis, the causative agent of plague. When overexpressed in vitro this protein is able to downregulate IL-1β- and LPS-dependent signalling to NFκB and to interact with the TIR adaptor protein MyD88. This interaction is dependent on a single proline residue. However, a Y. pestis knockout mutant lacking the TIR domain protein was not attenuated in virulence in a mouse model of bubonic plague. Minor alterations in the host cytokine response to the mutant were indicated, suggesting a potential subtle role in pathogenesis. The Y. pestis mutant also showed increased auto-aggregation and reduced survival in high-salinity conditions, phenotypes which may contribute to pathogenesis or survival.
Lominadze, David; Tyagi, Neetu; Sen, Utpal; Ovechkin, Alexander; Tyagi, Suresh C
High levels of homocysteine (Hcy), known as hyperhomocysteinemia (HHcy), are associated with cerebrovascular diseases, such as vascular dementia, stroke, and Alzheimer's disease. The γ-amino butyric acid (GABA) is an inhibitory neurotransmitter and a ligand of GABA-A receptor. By inhibiting excitatory response, it may decrease complications associated with vascular dementia and stroke. Hcy specifically competes with the GABA-A receptors and acts as an excitotoxic neurotransmitter. Previously, we have shown that Hcy increases levels of NADPH oxidase and reactive oxygen species (ROS), and decreases levels of thioredoxin and peroxiredoxin by antagonizing the GABA-A receptor. Hcy treatment leads to activation of matrix metalloproteinases (MMPs) in cerebral circulation by inducing redox stress and ROS. The hypothesis is that Hcy induces MMPs and suppresses tissue inhibitors of metalloproteinase (TIMPs), in part, by inhibiting the GABA-A receptor. This leads to degradation of the matrix and disruption of the blood brain barrier. The brain cortex of transgenic mouse model of HHcy (cystathionine β-synthase, CBS-/+) and GABA-A receptor null mice treated with and without muscimol (GABA-A receptor agonist) was analysed. The mRNA levels were measured by Q-RT-PCR. Levels of MMP-2, -9, -13, and TIMP-1, -2, -3, and -4 were evaluated by in situ labeling and PCR-gene arrays. Pial venular permeability to fluorescence-labeled albumin was assessed with intravital fluorescence microscopy. We found that Hcy increases metalloproteinase activity and decreases TIMP-4 by antagonizing the GABA-A receptor. The results demonstrate a novel mechanism in which brain microvascular permeability changes during HHcy and vascular dementias, and have therapeutic ramifications for microvascular disease in Alzheimer's patients.
Osguthorpe, D.J.; Hagler, A.T.
The androgen receptor (AR) plays a key role in a regulating gene expression in a variety of tissues, including the prostate. In the latter role it is one of the primary targets in the development of new chemotherapeutics for treatment of prostate cancer, as well as being the target of the most widely prescribed current drug, bicalutamide (Bcu), for this disease. In view of it’s importance, and the absence of a crystal structure for any antagonist-AR complex, we have carried out a series of molecular dynamics based simulations of the AR-Bcu complex and quantum mechanical (QM) calculations of Bcu, to elucidate the structural basis for antagonism of this key target. The structures which emerge show that bicalutamide antagonizes AR by accessing an additional binding pocket (B-site) adjacent to the hormone binding site (HBS), induced by displacing helix 12. This distorts the coactivator binding site and results in the inactivation of transcription. An alternative equienergetic conformational state of bicalutamide was found to bind in an expanded hormone pocket without materially perturbing either helix 12 or the coactivator binding site. Thus both the structural basis of antagonism and the mechanism underlying agonist properties displayed by bicalutamide in different environments may be rationalized in terms of these structures. In addition the antagonist structure and especially the induced second site (B-site) provides a structural framework for the design of novel antiandrogens. PMID:21466228
Osguthorpe, D J; Hagler, A T
The androgen receptor (AR) plays a key role in regulating gene expression in a variety of tissues, including the prostate. In that role, it is one of the primary targets in the development of new chemotherapeutics for treatment of prostate cancer and the target of the most widely prescribed current drug, bicalutamide (Bcu), for this disease. In view of its importance, and the absence of a crystal structure for any antagonist--AR complex, we have conducted a series of molecular dynamics-based simulations of the AR--Bcu complex and quantum mechanical (QM) calculations of Bcu, to elucidate the structural basis for antagonism of this key target. The structures that emerge show that bicalutamide antagonizes AR by accessing an additional binding pocket (B-site) adjacent to the hormone binding site (HBS), induced by displacing helix 12. This distorts the coactivator binding site and results in the inactivation of transcription. An alternative equienergetic conformational state of bicalutamide was found to bind in an expanded hormone pocket without materially perturbing either helix 12 or the coactivator binding site. Thus, both the structural basis of antagonism and the mechanism underlying agonist properties displayed by bicalutamide in different environments may be rationalized in terms of these structures. In addition, the antagonist structure and especially the induced second site (B-site) provide a structural framework for the design of novel antiandrogens.
Cheng, Ye; Zhou, Meili; Wang, Yan
Hypertension is one of the most important risk factors in cardiovascular disease and is the most common chronic disease. Mineralocorticoid receptor (MR) antagonists have been successfully used in clinic for the treatment of hypertension. Our study aims to investigate whether Arctigenin can antagonize MR and inhibit the transcription of Na/K-ATPase. The yeast two-hybrid assay was used to screen natural products and Arctigenin was identified as an MR antagonist. The direct binding of Arctigenin to MR was determined using assays based on surface plasmon resonance, differential scanning calorimetry and fluorescence quenching. Furthermore, results from mammalian one-hybrid and transcriptional activation experiments also confirmed that Arctigenin can potently antagonize MR in cells. We demonstrated that Arctigenin can decrease the level of Na/K-ATPase mRNA by antagonizing MR in HK-2 cells. Our findings show that Arctigenin can effectively decrease Na/K-ATPase transcription; thus highlight its potential as an anti-hypertensive drug lead compound. Our current findings demonstrate that Arctigenin is an antagonist of MR and effectively decreases the Na/K-ATPase 1 gene expression. Our work provides a hint for the drug discovery against cardiovascular disease.
Qing, Yu-Feng; Zhang, Quan-Bo; Zhou, Jing-Guo; Jiang, Li
We undertook this study to determine whether the altered toll-like receptor (TLR)4-nuclear factor κB (NFκB)-interleukin1β (IL1β) signaling in peripheral blood of gout patients could provide insights into the pathogenesis of primary gouty arthritis (GA). TLR4 mRNA, TLR4 and NFκBp65 proteins expression and IL1β production were measured in 52 acute GA (AGA) and 34 non-acute GA (NAGA) male patients and 78 male healthy subjects (HC). NFκBp65 transcriptional activity and IL1β production were measured after TLR4 inhibition with anti-TLR4 antibody in peripheral whole blood from 13 AGA patients. The TLR4, NFκBp65 and IL1β expression was significantly increased in the AGA group than those in the NAGA or HC group (P < 0.05, respectively), also the levels were higher in the NAGA group comparing with those in the HC group (P < 0.05, respectively). Furthermore, moderate positive correlations were observed between concentration of uric acid and the TLR4 mRNA level, serum IL1β production (r = 0.649, 0.616), and strong positive correlation was observed between TLR4 mRNA level and serum IL1β (r = 0.848) in 52 AGA patients. On the other hand, NFκBp65 level and IL1β production were dramatically reduced after TLR4 blockade with anti-TLR4 antibody in peripheral blood from the AGA patients (P < 0.05, respectively). TLR4-NFκB-IL1β signaling might play a crucial role in the development of acute inflammation in primary gout patients.
Lusher, Scott J.; Raaijmakers, Hans C. A.; Vu-Pham, Diep; Dechering, Koen; Lam, Tsang Wai; Brown, Angus R.; Hamilton, Niall M.; Nimz, Olaf; Bosch, Rolien; McGuire, Ross; Oubrie, Arthur; de Vlieg, Jacob
The progesterone receptor is able to bind to a large number and variety of ligands that elicit a broad range of transcriptional responses ranging from full agonism to full antagonism and numerous mixed profiles inbetween. We describe here two new progesterone receptor ligand binding domain x-ray structures bound to compounds from a structurally related but functionally divergent series, which show different binding modes corresponding to their agonistic or antagonistic nature. In addition, we present a third progesterone receptor ligand binding domain dimer bound to an agonist in monomer A and an antagonist in monomer B, which display binding modes in agreement with the earlier observation that agonists and antagonists from this series adopt different binding modes. PMID:21849509
Verstraete, Kenneth; Peelman, Frank; Braun, Harald; Lopez, Juan; Van Rompaey, Dries; Dansercoer, Ann; Vandenberghe, Isabel; Pauwels, Kris; Tavernier, Jan; Lambrecht, Bart N; Hammad, Hamida; De Winter, Hans; Beyaert, Rudi; Lippens, Guy; Savvides, Savvas N
The pro-inflammatory cytokine thymic stromal lymphopoietin (TSLP) is pivotal to the pathophysiology of widespread allergic diseases mediated by type 2 helper T cell (Th2) responses, including asthma and atopic dermatitis. The emergence of human TSLP as a clinical target against asthma calls for maximally harnessing its therapeutic potential via structural and mechanistic considerations. Here we employ an integrative experimental approach focusing on productive and antagonized TSLP complexes and free cytokine. We reveal how cognate receptor TSLPR allosterically activates TSLP to potentiate the recruitment of the shared interleukin 7 receptor α-chain (IL-7Rα) by leveraging the flexibility, conformational heterogeneity and electrostatics of the cytokine. We further show that the monoclonal antibody Tezepelumab partly exploits these principles to neutralize TSLP activity. Finally, we introduce a fusion protein comprising a tandem of the TSLPR and IL-7Rα extracellular domains, which harnesses the mechanistic intricacies of the TSLP-driven receptor complex to manifest high antagonistic potency.
Verstraete, Kenneth; Peelman, Frank; Braun, Harald; Lopez, Juan; Van Rompaey, Dries; Dansercoer, Ann; Vandenberghe, Isabel; Pauwels, Kris; Tavernier, Jan; Lambrecht, Bart N.; Hammad, Hamida; De Winter, Hans; Beyaert, Rudi; Lippens, Guy; Savvides, Savvas N.
The pro-inflammatory cytokine thymic stromal lymphopoietin (TSLP) is pivotal to the pathophysiology of widespread allergic diseases mediated by type 2 helper T cell (Th2) responses, including asthma and atopic dermatitis. The emergence of human TSLP as a clinical target against asthma calls for maximally harnessing its therapeutic potential via structural and mechanistic considerations. Here we employ an integrative experimental approach focusing on productive and antagonized TSLP complexes and free cytokine. We reveal how cognate receptor TSLPR allosterically activates TSLP to potentiate the recruitment of the shared interleukin 7 receptor α-chain (IL-7Rα) by leveraging the flexibility, conformational heterogeneity and electrostatics of the cytokine. We further show that the monoclonal antibody Tezepelumab partly exploits these principles to neutralize TSLP activity. Finally, we introduce a fusion protein comprising a tandem of the TSLPR and IL-7Rα extracellular domains, which harnesses the mechanistic intricacies of the TSLP-driven receptor complex to manifest high antagonistic potency. PMID:28368013
Oie, E; Bjønerheim, R; Grogaard, H K; Kongshaug, H; Smiseth, O A; Attramadal, H
Both myocardial and plasma endothelin-1 (ET-1) are elevated in congestive heart failure (CHF). However, the role played by endogenous ET-1 in the progression of CHF remains unknown. The aim of the present study was to investigate and correlate myocardial gene expression programs and left ventricular (LV) remodeling during chronic ET-receptor antagonism in CHF rats. After ligation of the left coronary artery, rats were randomized to oral treatment with a nonselective ET-receptor antagonist (bosentan, 100 mg . kg-1 . day-1, n = 11) or vehicle (saline, n = 13) for 15 days, starting 24 h after induction of myocardial infarction. Bosentan substantially attenuated LV dilatation during postinfarction failure as evaluated by echocardiography. Furthermore, bosentan decreased LV systolic and end-diastolic pressures and increased fractional shortening. Myocardial expression of preproET-1 mRNA and a fetal gene program characteristic of myocardial hypertrophy were increased in the CHF rats and were not affected by bosentan. Consistently, right ventricular-to-body weight ratios, diameters of cardiomyocytes, and echocardiographic analysis demonstrated a sustained hypertrophic response and a normalized relative wall thickness after intervention with bosentan. Thus the modest reduction of preload and afterload provided by bosentan substantially attenuates LV dilatation, causing improved pressure-volume relationships. However, the compensatory hypertrophic response was not altered by ET-receptor antagonism. Therefore, ET-1 does not appear to play a crucial role in the mechanisms of myocardial hypertrophy during the early phase of postinfarction failure.
Grieder, Taryn E; George, Olivier; Yee, Mandy; Bergamini, Michael A; Chwalek, Michal; Maal-Bared, Geith; Vargas-Perez, Hector; van der Kooy, Derek
Nicotine addiction is a worldwide epidemic that claims millions of lives each year. Genetic deletion of α5 nicotinic acetylcholine receptor (nAChR) subunits has been associated with increased nicotine intake, however, it remains unclear whether acute nicotine is less aversive or more rewarding, and whether mice lacking the α5 nAChR subunit can experience withdrawal from chronic nicotine. We used place conditioning and conditioned taste avoidance paradigms to examine the effect of α5 subunit-containing nAChR deletion (α5 -/-) on conditioned approach and avoidance behaviour in nondependent and nicotine-dependent and -withdrawn mice, and compared these motivational effects with those elicited after dopamine receptor antagonism. We show that nondependent α5 -/- mice find low, non-motivational doses of nicotine rewarding, and do not show an aversive conditioned response or taste avoidance to higher aversive doses of nicotine. Furthermore, nicotine-dependent α5 -/- mice do not show a conditioned aversive motivational response to withdrawal from chronic nicotine, although they continue to exhibit a somatic withdrawal syndrome. These effects phenocopy those observed after dopamine receptor antagonism, but are not additive, suggesting that α5 nAChR subunits act in the same pathway as dopamine and are critical for the experience of nicotine's aversive, but not rewarding motivational effects in both a nondependent and nicotine-dependent and -withdrawn motivational state. Genetic deletion of α5 nAChR subunits leads to a behavioural phenotype that exactly matches that observed after antagonizing dopamine receptors, thus we suggest that modulation of nicotinic receptors containing α5 subunits may modify dopaminergic signalling, suggesting novel therapeutic treatments for smoking cessation. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
Jiang, Fei; Meng, Di; Weng, Meiqian; Zhu, Weishu; Wu, Wenxue; Kasper, Dennis; Walker, W. Allan
Colonizing bacteria interacting with the immature, unlike the mature, human intestine favors inflammation over immune homeostasis. As a result, ten percent of premature infants under 1500 grams weight develop an inflammatory necrosis of the intestine after birth, e.g., necrotizing enterocolitis (NEC). NEC is a major health problem in this population causing extensive morbidity and mortality and an enormous expenditure of health care dollars. NEC can be prevented by giving preterm infants their mother’s expressed breast milk or ingesting selective probiotic organisms. Vaginally delivered, breast fed newborns develop health promoting bacteria (“pioneer” bacteria) which preferentially stimulate intestinal host defense and anti-inflammation. One such “pioneer” organism is Bacteroides fragilis with a polysaccharide (PSA) on its capsule. B. fragilis has been shown developmentally in intestinal lymphocytes and dendritic cells to produce a balanced T-helper cell (TH1/TH2) response and to reduce intestinal inflammation by activity through the TLR2 receptor stimulating IL-10 which inhibits IL-17 causing inflammation. No studies have been done on the role of B. fragilis PSA on fetal enterocytes and its increased inflammation. Accordingly, using human and mouse fetal intestinal models, we have shown that B. fragilis with PSA and PSA alone inhibits IL-1β-induced IL-8 inflammation in fetal and NEC intestine. We have also begun to define the mechanism for this unique inflammation noted in fetal intestine. We have shown that B. fragilis PSA anti-inflammation requires both the TLR2 and TLR4 receptor and is in part mediated by the AP1 transcription factor (TLR2) which is developmentally regulated. These observations may help to devise future preventative treatments of premature infants against NEC. PMID:28278201
Dugovic, Christine; Shelton, Jonathan E.; Yun, Sujin; Bonaventure, Pascal; Shireman, Brock T.; Lovenberg, Timothy W.
In accordance with the prominent role of orexins in the maintenance of wakefulness via activation of orexin-1 (OX1R) and orexin-2 (OX2R) receptors, various dual OX1/2R antagonists have been shown to promote sleep in animals and humans. While selective blockade of OX2R seems to be sufficient to initiate and prolong sleep, the beneficial effect of additional inhibition of OX1R remains controversial. The relative contribution of OX1R and OX2R to the sleep effects induced by a dual OX1/2R antagonist was further investigated in the rat, and specifically on rapid eye movement (REM) sleep since a deficiency of the orexin system is associated with narcolepsy/cataplexy based on clinical and pre-clinical data. As expected, the dual OX1/2R antagonist SB-649868 was effective in promoting non-REM (NREM) and REM sleep following oral dosing (10 and 30 mg/kg) at the onset of the dark phase. However, a disruption of REM sleep was evidenced by a more pronounced reduction in the onset of REM as compared to NREM sleep, a marked enhancement of the REM/total sleep ratio, and the occurrence of a few episodes of direct wake to REM sleep transitions (REM intrusion). When administered subcutaneously, the OX2R antagonist JNJ-10397049 (10 mg/kg) increased NREM duration whereas the OX1R antagonist GSK-1059865 (10 mg/kg) did not alter sleep. REM sleep was not affected either by OX2R or OX1R blockade alone, but administration of the OX1R antagonist in combination with the OX2R antagonist induced a significant reduction in REM sleep latency and an increase in REM sleep duration at the expense of the time spent in NREM sleep. These results indicate that additional blockade of OX1R to OX2R antagonism elicits a dysregulation of REM sleep by shifting the balance in favor of REM sleep at the expense of NREM sleep that may increase the risk of adverse events. Translation of this hypothesis remains to be tested in the clinic. PMID:24592208
Dugovic, Christine; Shelton, Jonathan E; Yun, Sujin; Bonaventure, Pascal; Shireman, Brock T; Lovenberg, Timothy W
In accordance with the prominent role of orexins in the maintenance of wakefulness via activation of orexin-1 (OX1R) and orexin-2 (OX2R) receptors, various dual OX1/2R antagonists have been shown to promote sleep in animals and humans. While selective blockade of OX2R seems to be sufficient to initiate and prolong sleep, the beneficial effect of additional inhibition of OX1R remains controversial. The relative contribution of OX1R and OX2R to the sleep effects induced by a dual OX1/2R antagonist was further investigated in the rat, and specifically on rapid eye movement (REM) sleep since a deficiency of the orexin system is associated with narcolepsy/cataplexy based on clinical and pre-clinical data. As expected, the dual OX1/2R antagonist SB-649868 was effective in promoting non-REM (NREM) and REM sleep following oral dosing (10 and 30 mg/kg) at the onset of the dark phase. However, a disruption of REM sleep was evidenced by a more pronounced reduction in the onset of REM as compared to NREM sleep, a marked enhancement of the REM/total sleep ratio, and the occurrence of a few episodes of direct wake to REM sleep transitions (REM intrusion). When administered subcutaneously, the OX2R antagonist JNJ-10397049 (10 mg/kg) increased NREM duration whereas the OX1R antagonist GSK-1059865 (10 mg/kg) did not alter sleep. REM sleep was not affected either by OX2R or OX1R blockade alone, but administration of the OX1R antagonist in combination with the OX2R antagonist induced a significant reduction in REM sleep latency and an increase in REM sleep duration at the expense of the time spent in NREM sleep. These results indicate that additional blockade of OX1R to OX2R antagonism elicits a dysregulation of REM sleep by shifting the balance in favor of REM sleep at the expense of NREM sleep that may increase the risk of adverse events. Translation of this hypothesis remains to be tested in the clinic.
Joesting, Jennifer J.; Moon, Morgan L.; Gainey, Stephen J.; Tisza, Brittany L.; Blevins, Neil A.; Freund, Gregory G.
Objective: Weight-loss is a near societal obsession and many diet programs use significant calorie restriction including fasting/short term starvation to generate rapid effects. Fasting is also a well-recognized cause of immunosuppression especially within the innate immune system. In this study, we sought to determine if the IL-1 arm of the neuroimmune system was down-regulated by a 24 h fast and how fasting might generate this effect. Design: Mice were allowed ad libitum access to food or had food withheld for 24 h. Expression of the endogenous IL-1 antagonists, IL-1 receptor type 2 (IL-1R2), and IL-1 receptor antagonist (IL-1RA) was determined as were sickness behaviors before and after IL-1β administration. Results: Fasting markedly increased gene expression of IL-1R2 (83-fold in adipose tissue, 9.5-fold in liver) and IL-1RA (68-fold in liver). Fasted mice were protected from IL-1β-induced weight-loss, hypoglycemia, loss of locomotor, and social anxiety. These protections were coupled to a large positive interaction of fasting and IL-1β on IL-1R2 gene expression in adipose tissue and liver (2.6- and 1.6-fold, respectively). Fasting not only increased IL-1RA and IL-1R2 protein 2.5- and 3.2-fold, respectively, in liver but also increased IL-1R2 1.8-fold in adipose tissue. Fasting, in turn, triggered a 2.4-fold increase in plasma free-fatty acids (FFAs) and a 2.1-fold increase in plasma corticosterone. Inhibition, of glucocorticoid action with mifepristone did not impact fasting-dependent IL-1R2 or IL-1RA gene expression. Administration of the FFA, palmitate, to mice increased liver IL-1R2 and IL-1RA gene expression by 14- and 11-fold, respectively. Conclusion: These findings indicate that fasting augments expression of endogenous IL-1 antagonists inducing IL-1 resistance. Fasting-induced increases in plasma FFAs appears to be a signal that drives immunosuppression during fasting/short term starvation. PMID:25071776
to allow the cells to swell. 50 µl of 10% Nonidet P - 40 was added to the cells and briefly centrifuged. The nuclear pellet was resuspended in...protein 10 (IP-10). A conserved sequence, (F/Y)-(V/L/I)-( P /G), called the BB- loop appears in the TIR domain of most members of the TLR/IL-1R family...from 7 structural analogs based on the tripeptide sequence of the BB-loop [(F/Y)-(V/L/I)-( P /G)] of the Toll/IL-1 receptor (TIR) domain binding
Quinlan, Matthew G; Almey, Anne; Caissie, Meghen; LaChappelle, Ivonne; Radiotis, George; Brake, Wayne G
Estradiol (E2) has been shown to influence learning and memory systems used by female rats to find a reward. Rats with high levels of E2 tend to use allocentric, or place, memory while rats with low levels of E2 use egocentric, or response, memory. It has been shown that systemic dopamine receptor antagonism interacts with E2 to affect which memory system is used. Here, dopamine antagonists were administered directly into either the dorsal striatum or nucleus accumbens to determine where in the brain this interaction takes place. Seventy-four young adult, female, Sprague-Dawley rats were trained and tested in a modified plus-maze. All rats were ovariectomized, received a subcutaneous low E2 implant, and were implanted with bilateral cannulae into either the dorsal striatum or the nucleus accumbens. Additionally, high E2 rats received daily injections of E2 in a sesame oil solution while low E2 rats received daily injections of vehicle. After reaching criterion levels of performance in a plus-maze task, rats were administered microinjections of either a dopamine D1 receptor (SCH 23390; 0.1 μg/ml and 0.01 μg/ml) or D2 receptor (raclopride; 2 μg/ml and 0.5 μg/ml) antagonist or a vehicle control (saline) in a counterbalanced manner. High E2 rats exhibited a trend towards a place memory bias while low E2 rats showed a response memory bias. Dorsal striatal administration of a D1, but not D2, dopamine receptor antagonist caused a switch in the memory system used by both high and low E rats. There was no significant effect of dopamine receptor antagonism in the nucleus accumbens group. Thus, E2 determined which memory system controlled behavior in a plus-maze task. Moreover, this effect was modulated by dopamine D1R antagonism in the dorsal but not ventral striatum suggesting that memory systems are, in part, mediated by E2 and dopamine in this region. Copyright © 2013 Elsevier Inc. All rights reserved.
Degroot, Aldemar; Köfalvi, Attila; Wade, Mark R; Davis, Richard J; Rodrigues, Ricardo J; Rebola, Nelson; Cunha, Rodrigo A; Nomikos, George G
Evidence indicates that blockade of cannabinoid receptors increases acetylcholine (ACh) release in brain cortical regions. Although it is assumed that this type of effect is mediated through CB1 receptor (CB1R) antagonism, several in vitro functional studies recently have suggested non-CB1R involvement. In addition, neither the precise neuroanatomical site nor the exact mechanisms underlying this effect are known. We thoroughly examined these issues using a combination of systemic and local administration of CB1R antagonists, different methods of in vivo microdialysis, CB1R knockout (KO) mice, tissue measurements of ACh, and immunochemistry. First, we showed that systemic injections of the CB1R antagonists N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboximide hydrochloride (SR-141716A) and N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2, 4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251) dose-dependently increased hippocampal ACh efflux. Likewise, local hippocampal, but not septal, infusions of SR141716A or AM251 increased hippocampal ACh release. It is noteworthy that the stimulatory effects of systemically administered CB1R antagonists on hippocampal ACh release were completely abolished in CB1R KO mice. CB1R KO mice had similar basal but higher stress-enhanced hippocampal ACh levels compared with wild-type controls. It is interesting that dopamine D1 receptor antagonism counteracted the stimulatory effect of CB1R blockade on hippocampal ACh levels. Finally, immunohistochemical methods revealed that a high proportion of CB1R-positive nerve terminals were found in hippocampus and confirmed the colocalization of CB1 receptors with cholinergic and dopaminergic nerve terminals. In conclusion, hippocampal ACh release may specifically be controlled through CB1Rs located on both cholinergic and dopaminergic neuronal projections, and CB1R antagonism increases hippocampal ACh release, probably through both a direct
Lempereur, Maëlle; Majewska, Claire; Brunquers, Amandine; Wongpramud, Sumalee; Valet, Bénédicte; Janssens, Philippe; Dillemans, Monique; Van Nedervelde, Laurence; Gallo, Dominique
Tetrahydro-iso-alpha acids commonly called THIAA or Tetra are modified hop acids extracted from hop (Humulus lupulus L.) which are frequently used in brewing industry mainly in order to provide beer bitterness and foam stability. Interestingly, molecular structure of tetrahydro-iso-alpha acids is close to a new type of estrogen receptor alpha (ERα) antagonists aimed at disrupting the binding of coactivators containing an LxxLL motif (NR-box). In this work we show that THIAA decreases estradiol-stimulated proliferation of MCF-7 (ERα-positive breast cancer cells). Besides, we show that it inhibits ERα transcriptional activity. Interestingly, this extract fails to compete with estradiol for ERα binding and does not significantly impact the receptor turnover rate in MCF-7 cells, suggesting that it does not act like classical antiestrogens. Hence, we demonstrate that THIAA is able to antagonize ERα estradiol-induced recruitment of the LxxLL binding motif.
Lempereur, Maëlle; Majewska, Claire; Brunquers, Amandine; Wongpramud, Sumalee; Valet, Bénédicte; Janssens, Philippe; Dillemans, Monique; Van Nedervelde, Laurence; Gallo, Dominique
Tetrahydro-iso-alpha acids commonly called THIAA or Tetra are modified hop acids extracted from hop (Humulus lupulus L.) which are frequently used in brewing industry mainly in order to provide beer bitterness and foam stability. Interestingly, molecular structure of tetrahydro-iso-alpha acids is close to a new type of estrogen receptor alpha (ERα) antagonists aimed at disrupting the binding of coactivators containing an LxxLL motif (NR-box). In this work we show that THIAA decreases estradiol-stimulated proliferation of MCF-7 (ERα-positive breast cancer cells). Besides, we show that it inhibits ERα transcriptional activity. Interestingly, this extract fails to compete with estradiol for ERα binding and does not significantly impact the receptor turnover rate in MCF-7 cells, suggesting that it does not act like classical antiestrogens. Hence, we demonstrate that THIAA is able to antagonize ERα estradiol-induced recruitment of the LxxLL binding motif. PMID:27190515
Park, Seon Joo; Yang, Heehong; Lee, Seung Hwan; Song, Hyun Seok; Park, Chul Soon; Bae, Joonwon; Kwon, Oh Seok; Park, Tai Hyun; Jang, Jyongsik
The field-effect transistor (FET) has been used in the development of diagnostic tools for several decades, leading to high-performance biosensors. Therefore, the FET platform can provide the foundation for the next generation of analytical methods. A major role of G-protein-coupled receptors (GPCRs) is in the transfer of external signals into the cell and promoting human body functions; thus, their principle application is in the screening of new drugs. The research community uses efficient systems to screen potential GPCR drugs; nevertheless, the need to develop GPCR-conjugated analytical devices remains for next-generation new drug screening. In this study, we proposed an approach for studying receptor agonism and antagonism by combining the roles of FETs and GPCRs in a dopamine receptor D1 (DRD1)-conjugated FET system, which is a suitable substitute for conventional cell-based receptor assays. DRD1 was reconstituted and purified to mimic native binding pockets that have highly discriminative interactions with DRD1 agonists/antagonists. The real-time responses from the DRD1-nanohybrid FET were highly sensitive and selective for dopamine agonists/antagonists, and their maximal response levels were clearly different depending on their DRD1 affinities. Moreover, the equilibrium constants (K) were estimated by fitting the response levels. Each K value indicates the variation in the affinity between DRD1 and the agonists/antagonists; a greater K value corresponds to a stronger DRD1 affinity in agonism, whereas a lower K value in antagonism indicates a stronger dopamine-blocking effect.
Sang, Jian-Feng; Shi, Xiao-Lei; Han, Bing; Huang, Xu; Huang, Tao; Ren, Hao-Zhen; Ding, Yi-Tao
To study the therapeutic effects of mesenchymal stem cells (MSCs) and an interleukin-1 receptor antagonist (IL-1Ra) in acute liver failure. Chinese experimental miniature swine (15 ± 3 kg, 5-8 mo) were obtained from the Laboratory Animal Centre of the Affiliated Drum Tower Hospital of Nanjing University Medical School. Acute liver failure was induced via 85% hepatectomy, and animals were treated by MSC transplantation combined with IL-1Ra injection. Blood samples were collected for hepatic function analysis, and the living conditions and survival time were recorded. Liver injury was histologically analyzed. Hepatic cell regeneration and apoptosis were studied by Ki67 immunohistochemistry and terminal deoxynucleotidyl transferase dUTP nick end labeling, respectively. The levels of protein kinase B and nuclear factor-κB expression were analyzed by Western blotting. MSCs were infected with a lentivirus for expression of green fluorescent protein (GFP) for subsequent identification; 97.3% of the MSCs were positive for GFP as assessed by flow cytometry. Additional flow cytometric analysis of cell surface marker expression demonstrated that > 90% of GFP-expressing MSCs were also positive for CD29, CD44, and CD90, indicating that most of these cells expressed typical markers of MSCs, and the population of MSCs was almost pure. Transplantation of MSCs in combination with 2 mg/kg IL-1Ra therapy significantly improved survival time compared to the acute liver failure model group (35.3 ± 6.7 d vs 17.3 ± 5.5 d, P < 0.05). Combined therapy also promoted improvement in serum inflammatory cytokines and biochemical conditions. The observed hepatic histopathologic score was significantly lower in the group with combined therapy than in the model group (3.50 ± 0.87 vs 8.17 ± 1.26, P < 0.01). In addition, liver cell apoptosis in the combined therapy group was significantly inhibited (18.1 ± 2.1% vs 70.8 ± 3.7%, P < 0.01), and hepatic cell regeneration increased. A significant
Dayer, Jean-Michel; Oliviero, Francesca; Punzi, Leonardo
The history of what, in 1979, was called interleukin-1 (IL-1), orchestrator of leukocyte inter-communication, began many years before then, initially by the observation of fever induction via the endogenous pyrogen (EP) (1974) and then in rheumatology on the role in tissue destruction in rheumatoid diseases via the induction of collagenase and PGE2 in human synovial cells by a mononuclear cell factor (MCF) (1977). Since then, the family has exploded to presently 11 members as well as many membrane-bound and soluble receptor forms. The discovery of a natural Interleukin-1 receptor antagonist (IL-1Ra) in human biological fluids has highlighted the importance of IL-1 and IL-1Ra in human diseases. Evidence delineating its role in autoinflammatory syndromes and the elucidation of the macromolecular complex referred to as "inflammasome" have been instrumental to our understanding of the link with IL-1. At present, the IL-1blockade as therapeutic approach is crucial for many hereditary autoinflammatory diseases, as well as for adult-onset Still's disease, crystal-induced arthropathies, certain skin diseases including neutrophil-triggered skin diseases, Behçet's disease and deficiency of IL-1Ra and other rare fever syndromes. Its role is only marginally important in rheumatoid arthritis and is still under debate with regard to osteoarthritis, type 2 diabetes mellitus, cardiovascular diseases and cancer. This brief historical review focuses on some aspects of IL-1, mainly IL-1β and IL-Ra, in rheumatology. There are many excellent reviews focusing on the IL-1 family in general or with regard to specific diseases or biological discoveries.
Heptahelical, G protein-coupled or seven transmembrane-spanning receptors, such as the β-adrenergic and the angiotensin II type 1 receptors, are the most diverse and therapeutically important family of receptors in the human genome, playing major roles in the physiology of various organs/tissues including the heart and blood vessels. Ligand binding activates heterotrimeric G proteins that transmit intracellular signals by regulating effector enzymes or ion channels. G protein signaling is terminated, in large part, by phosphorylation of the agonist-bound receptor by the G-protein coupled receptor kinases (GRKs), followed by βarrestin binding, which uncouples the phosphorylated receptor from the G protein and subsequently targets the receptor for internalization. As the receptor-βarrestin complex enters the cell, βarrestin-1 and -2, the two mammalian βarrestin isoforms, serve as ligand-regulated scaffolds that recruit a host of intracellular proteins and signal transducers, thus promoting their own wave of signal transduction independently of G-proteins. A constantly increasing number of studies over the past several years have begun to uncover specific roles played by these ubiquitously expressed receptor adapter proteins in signal transduction of several important heptahelical receptors regulating the physiology of various organs/ systems, including the cardiovascular (CV) system. Thus, βarrestin-dependent signaling has increasingly been implicated in CV physiology and pathology, presenting several exciting opportunities for therapeutic intervention in the treatment of CV disorders. Additionally, the discovery of this novel mode of heptahelical receptor signaling via βarrestins has prompted a revision of classical pharmacological concepts such as receptor agonism/antagonism, as well as introduction of new terms such as "biased signaling", which refers to ligand-specific activation of selective signal transduction pathways by the very same receptor. The
Klenotich, S J; Ho, E V; McMurray, M S; Server, C H; Dulawa, S C
Anorexia nervosa (AN) is an eating disorder characterized by severe hypophagia and weight loss, and an intense fear of weight gain. Activity-based anorexia (ABA) refers to the weight loss, hypophagia and paradoxical hyperactivity that develops in rodents exposed to running wheels and restricted food access, and provides a model for aspects of AN. The atypical antipsychotic olanzapine was recently shown to reduce both AN symptoms and ABA. We examined which component of the complex pharmacological profile of olanzapine reduces ABA. Mice received 5-HT2A/2C, 5-HT3, dopamine D1-like, D2, D3 or D2/3 antagonist treatment, and were assessed for food intake, body weight, wheel running and survival in ABA. D2/3 receptor antagonists eticlopride and amisulpride reduced weight loss and hypophagia, and increased survival during ABA. Furthermore, amisulpride produced larger reductions in weight loss and hypophagia than olanzapine. Treatment with either D3 receptor antagonist SB277011A or D2 receptor antagonist L-741,626 also increased survival. All the other treatments either had no effect or worsened ABA. Overall, selective antagonism of D2 and/or D3 receptors robustly reduces ABA. Studies investigating the mechanisms by which D2 and/or D3 receptors regulate ABA, and the efficacy for D2/3 and/or D3 antagonists to treat AN, are warranted. PMID:26241351
Jesus, Adriana A.; Goldbach-Mansky, Raphaela
Monogenic autoinflammatory syndromes present with excessive systemic inflammation including fever, rashes, arthritis, and organ-specific inflammation and are caused by defects in single genes encoding proteins that regulate innate inflammatory pathways. Pathogenic variants in two interleukin-1 (IL-1)–regulating genes, NLRP3 and IL1RN, cause two severe and early-onset autoinflammatory syndromes, CAPS (cryopyrin associated periodic syndromes) and DIRA (deficiency of IL-1 receptor antagonist). The discovery of the mutations that cause CAPS and DIRA led to clinical and basic research that uncovered the key role of IL-1 in an extended spectrum of immune dysregulatory conditions. NLRP3 encodes cryopyrin, an intracellular “molecular sensor” that forms a multimolecular platform, the NLRP3 inflammasome, which links “danger recognition” to the activation of the proinflammatory cytokine IL-1β. The success and safety profile of drugs targeting IL-1 in the treatment of CAPS and DIRA have encouraged their wider use in other autoinflammatory syndromes including the classic hereditary periodic fever syndromes (familial Mediterranean fever, TNF receptor–associated periodic syndrome, and hyperimmunoglobulinemia D with periodic fever syndrome) and additional immune dysregulatory conditions that are not genetically well defined, including Still’s, Behcet’s, and Schnitzler diseases. The fact that the accumulation of metabolic substrates such as monosodium urate, ceramide, cholesterol, and glucose can trigger the NLRP3 inflammasome connects metabolic stress to IL-1β-mediated inflammation and provides a rationale for therapeutically targeting IL-1 in prevalent diseases such as gout, diabetes mellitus, and coronary artery disease. PMID:24422572
Injury-induced platelet-derived growth factor receptor-alpha expression mediated by interleukin-1beta (IL-1beta) release and cooperative transactivation by NF-kappaB and ATF-4: IL-1beta facilitates HDAC-1/2 dissociation from promoter.
Zhang, Ning; Khachigian, Levon M
Platelet-derived growth factors are a family of potent mitogens and chemoattractants for fibroblasts and other cells of mesenchymal origin. Platelet-derived growth factor (PDGF) dimeric ligands (composed of A-, B-, C-, and D-chains) exert their biological activity through high affinity interactions with cell surface receptor subunits (alpha and beta). PDGF-receptor-alpha is widely implicated in the pathogenesis of hyperplastic fibrotic disease, yet the molecular mechanisms controlling its expression in response to injury are poorly understood. Here we show that PDGF-R alpha expression is induced in fibroblasts by mechanical injury and interleukin (IL)-1beta, which was abolished by neutralizing IL-1beta antibodies in the culture supernatant or inhibitors of NF-kappaB. Chromatin immunoprecipitation and electrophoretic mobility shift assays revealed the existence of a new NF-kappaB binding site at -531/-521 bp in the PDGF-R alpha promoter. We have recently shown that ATF-4 is also induced by injury (Malabanan, K. P., Kanellakis, P., Bobik, A., and Khachigian, L. M. (2008) Circ. Res. 103, 378-387), and we demonstrate here that ATF-4 binds a novel element -259/-254 and stimulates PDGF-R alpha transcription. ATF-4 and NF-kappaB interact, occupy the PDGF-R alpha promoter, and induce PDGF-R alpha transcription in a cooperative manner. IL-1beta facilitates the dissociation of histone deacetylase (HDAC)-1/2 from the PDGF-R alpha promoter, whereas the HDAC inhibitors suberoylanilide hydroxamic acid and trichostatin A potentiate IL-1beta induction of PDGF-R alpha transcription. These findings, taken together, demonstrate that injury stimulates IL-1beta secretion by fibroblasts, which activates NF-kappaB and ATF-4 and stimulates interaction with the PDGF-R alpha promoter, triggering PDGF-R alpha transcription. Physical and functional interactions between NF-kappaB and ATF-4 have not been reported in any gene. This is also the first report of HDAC regulation of PDGF-R alpha
Ruh, M F; Bi, Y; Cox, L; Berk, D; Howlett, A C; Bellone, C J
Environmental estrogens or estrogen disrupters have recently received a great deal of attention because of their potential health impact on reproductive tissues. Few, if any, studies have been made on the impact of these compounds on the immune system. We sought to determine the activities of various environmental estrogens on the modulation of the interleukin-1beta (IL-1beta) gene in a model monocytic cell line, hER + IL-1beta-CAT+. This cell line stably transfected with the human estrogen receptor, and an IL-1beta promoter construct fused to the CAT reporter gene allows us to monitor the effect of estrogenic compounds on IL-1beta promoter activity. 17beta-estradiol (E2) markedly enhanced lipopolysaccharide- (LPS) induced IL-1beta promoter-driven CAT activity in a dose-dependent manner. The mycotoxins alpha-zearalenol and zearalenone both exhibited full agonist activity, but at lower potencies, with EC50 values of 1.8 and 54 nM, respectively, compared with E2 at 0.5 nM. In addition, genistein was a very low-potency agonist, having an EC50 of 1.5 microM. Similar to the E2 response, the slope factors for alpha-zearalenol, zearalenone, and genistein were close to 3.0, suggesting positive cooperativity in the estrogenic response. The activity of the mycotoxins appeared to be mediated through the estrogen receptor, since both the antiestrogens H1285 and ICI 182,780 effectively inhibited their agonist activity in a dose-dependent manner. Representative environmental estrogenic compounds both from plant and industrial sources were also tested. Unlike the mycoestrogens, none of the compounds, with the exception of genistein, synergized with LPS to enhance IL-1beta promoter activity. When tested for antiestrogenic activity, the industrial compound 4-octylphenol was able to antagonize the response to E2; however, the response was three orders of magnitude less potent than H 1285. Naringenin, a plant flavonoid, showed little or no ability to antagonize the response to E2
Hennen, Stephanie; Kodra, János T; Soroka, Vladyslav; Krogh, Berit O; Wu, Xiaoai; Kaastrup, Peter; Ørskov, Cathrine; Rønn, Sif G; Schluckebier, Gerd; Barbateskovic, Silvia; Gandhi, Prafull S; Reedtz-Runge, Steffen
The Glucagon-like peptide-1 receptor (GLP-1R) is a member of the class B G protein-coupled receptor (GPCR) family and a well-established target for the treatment of type 2 diabetes. The N-terminal extracellular domain (ECD) of GLP-1R is important for GLP-1 binding and the crystal structure of the GLP-1/ECD complex was reported previously. The first structure of a class B GPCR transmembrane (TM) domain was solved recently, but the full length receptor structure is still not well understood. Here we describe the molecular details of antibody-mediated antagonism of the GLP-1R using both in vitro pharmacology and x-ray crystallography. We showed that the antibody Fab fragment (Fab 3F52) blocked the GLP-1 binding site of the ECD directly and thereby acts as a competitive antagonist of native GLP-1. Interestingly, Fab 3F52 also blocked a short peptide agonist believed to engage primarily the transmembrane and extracellular loop region of GLP-1R, whereas functionality of an allosteric small-molecule agonist was not inhibited. This study has implications for the structural understanding of the GLP-1R and related class B GPCRs, which is important for the development of new and improved therapeutics targeting these receptors.
Hennen, Stephanie; Kodra, János T.; Soroka, Vladyslav; Krogh, Berit O.; Wu, Xiaoai; Kaastrup, Peter; Ørskov, Cathrine; Rønn, Sif G.; Schluckebier, Gerd; Barbateskovic, Silvia; Gandhi, Prafull S.; Reedtz-Runge, Steffen
The Glucagon-like peptide-1 receptor (GLP-1R) is a member of the class B G protein-coupled receptor (GPCR) family and a well-established target for the treatment of type 2 diabetes. The N-terminal extracellular domain (ECD) of GLP-1R is important for GLP-1 binding and the crystal structure of the GLP-1/ECD complex was reported previously. The first structure of a class B GPCR transmembrane (TM) domain was solved recently, but the full length receptor structure is still not well understood. Here we describe the molecular details of antibody-mediated antagonism of the GLP-1R using both in vitro pharmacology and x-ray crystallography. We showed that the antibody Fab fragment (Fab 3F52) blocked the GLP-1 binding site of the ECD directly and thereby acts as a competitive antagonist of native GLP-1. Interestingly, Fab 3F52 also blocked a short peptide agonist believed to engage primarily the transmembrane and extracellular loop region of GLP-1R, whereas functionality of an allosteric small-molecule agonist was not inhibited. This study has implications for the structural understanding of the GLP-1R and related class B GPCRs, which is important for the development of new and improved therapeutics targeting these receptors. PMID:27196125
Cabrera, Susanne M; Wang, Xujing; Chen, Yi-Guang; Jia, Shuang; Kaldunski, Mary L; Greenbaum, Carla J; Mandrup-Poulsen, Thomas; Hessner, Martin J
It was hypothesized that IL-1 antagonism would preserve β-cell function in new onset Type 1 diabetes (T1D). However, the Anti-Interleukin-1 in Diabetes Action (AIDA) and TrialNet Canakinumab (TN-14) trials failed to show efficacy of IL-1 receptor antagonist (IL-1Ra) or canakinumab, as measured by stimulated C-peptide response. Additional measures are needed to define immune state changes associated with therapeutic responses. Here, we studied these trial participants with plasma-induced transcriptional analysis. In blinded analyses, 70.2% of AIDA and 68.9% of TN-14 participants were correctly called to their treatment arm. While the transcriptional signatures from the two trials were distinct, both therapies achieved varying immunomodulation consistent with IL-1 inhibition. On average, IL-1 antagonism resulted in modest normalization relative to healthy controls. At endpoint, signatures were quantified using a gene ontology-based inflammatory index, and an inverse relationship was observed between measured inflammation and stimulated C-peptide response in IL-1Ra- and canakinumab-treated patients. Cytokine neutralization studies showed that IL-1α and IL-1β additively contribute to the T1D inflammatory state. Finally, analyses of baseline signatures were indicative of later therapeutic response. Despite the absence of clinical efficacy by IL-1 antagonist therapy, transcriptional analysis detected immunomodulation and may yield new insight when applied to other clinical trials.
Lindroos, P M; Coin, P G; Badgett, A; Morgan, D L; Bonner, J C
Enhanced proliferation of fibroblasts is a primary characteristic of lung fibrosis. Macrophage-secreted platelet-derived growth factor (PDGF) is a potent mitogen and chemoattractant for lung fibroblasts. The magnitude of the fibroblast PDGF response is dependent on the number of PDGF receptor alpha (PDGF-R alpha) relative to PDGF-R beta at the cell surface. We recently reported that upregulation of the PDGF-R alpha subtype by interleukin (IL)-1beta results in enhanced lung fibroblast proliferation in response to PDGF-AA, PDGF-AB, and PDGF-BB whereas transforming growth factor (TGF)-beta1 has the opposite effect. Both IL-1beta and TGF-beta1 are produced by particle-activated macrophages in vivo and in vitro. We studied the net effect of macrophage conditioned medium (MOCM), which contains both IL-1beta and TGF-beta1, on the expression of the lung fibroblast PDGF receptor system. MOCM obtained from unstimulated, titanium dioxide (TiO2)-, chrysotile asbestos-, or residual oil fly ash (ROFA)-exposed macrophages in vitro increased [125I]PDGF-AA binding 3-, 6-, 6-, and 20-fold, respectively. These increases correlated with increased PDGF-R alpha mRNA and protein expression as shown by northern and western assays. PDGF-AB and -BB-stimulated [3H]thymidine incorporation by fibroblasts was enhanced 5-, 5-, 10-, and 20-fold by pretreatment with MOCM from unstimulated, TiO2-, asbestos-, and ROFA-exposed macrophages, respectively. [125I]PDGF-AA binding experiments using the IL-1 receptor antagonist blocked the upregulatory effect of all MOCM samples. Latent TGF-beta1 present in MOCM was activated by acid treatment, inhibiting upregulation by approximately 60%, a result similar to experiments with IL-1beta and TGF-beta1 mixtures. Treatment with a TGF-beta neutralizing antibody restored full upregulatory activity to acidified MOCM. Thus activated macrophages increase lung fibroblast PDGF-R alpha primarily due to the secretion of IL-1beta. Intratracheal instillation of ROFA
van de Veerdonk, Frank L.; Netea, Mihai G.
The interleukin-1 (IL 1) family of ligands is associated with acute and chronic inflammation, and plays an essential role in the non-specific innate response to infection. The biological properties of IL 1 family ligands are typically pro-inflammatory. The IL 1 family has 11 family members and can be categorized into subfamilies according to the length of their precursor and the length of the propiece for each precursor (Figure 1). The IL 1 subfamily consists of IL 1α, IL 1β, and IL 33, with the longest propieces of the IL 1 family. IL 18 and IL 37 belong to the IL 18 subfamily and contain smaller propieces than IL 1 and IL-33. Since IL 37 binds to the IL 18Rα chain it is part of the IL 18 subfamily, however it remains to be elucidated how the propiece of IL 37 is removed. IL 36α, β, and γ as well as IL 36 Ra belong to the IL 36 subfamily. In addition, IL 38 likely belongs to this family since it has the ability to bind to the IL 36R. The IL 36 subfamily has the shortest propiece. The one member of the IL 1 family that cannot be categorized in these subfamilies is IL 1 receptor antagonist (IL 1Ra), which has a signal peptide and is readily secreted. In the present review we will describe the biological functions of the IL-1F members and new insights in their biology. PMID:23847614
Kim, Jaekyoon; Frick, Karyn M
Exogenous treatment with the potent estrogen 17β-estradiol (E2) or selective estrogen receptor α/β (ERα/β) agonists enhances the consolidation of hippocampal-dependent object recognition (OR) and object placement (OP) memories in ovariectomized rodents. Although such data suggest that individual ERs are sufficient for memory consolidation, the necessity of a given ER for memory consolidation can only be demonstrated by blocking receptor function, for example with an ER antagonist. However, the effects on memory of antagonizing ERα or ERβ function are not well understood. Moreover, ER antagonism in ovariectomized subjects also provides indirect information about the role of individual ERs in the memory-enhancing effects of local hippocampal E2 synthesis. Therefore, this study used pharmacological inhibition of ERα and ERβ to elucidate the importance of each ER to memory consolidation. Specifically, we examined effects on OR and OP memory consolidation of immediate post-training dorsal hippocampal (DH) infusion of MPP and PHTPP, selective antagonists for ERα and ERβ, respectively. Each drug exhibited a distinct effect on OR and OP. DH infusion of MPP (0.28 or 2.78ng/hemisphere) impaired memory in OP, but not OR. However, DH infusion of PHTPP (0.21 or 2.12ng/hemisphere) impaired memory in both OR and OP. Neither drug affected the elapsed time to accumulate object exploration in either task, suggesting a specific effect on memory. These results indicate that activation of either classical ER within the dorsal hippocampus is important for hippocampal memory consolidation in ovariectomized mice, but suggest that specific ER involvement is memory- or task-specific. The findings also indirectly support a role for ERα and ERβ in mediating the memory-enhancing effects of hippocampally-synthesized E2. Copyright © 2017 Elsevier Ltd. All rights reserved.
Martin-Fardon, Rémi; Strong, Elena M; Weiss, Friedbert
σ₁ Receptors have been implicated in cognitive function, anxiety, depression, and the regulation of stress responses. In addition, σ₁ receptors have been shown to participate in the behavioral and motivational effects of psychostimulants. Recent studies have shown that σ₁ receptor antagonism prevents ethanol-induced conditioned place preference in mice and excessive drinking in alcohol-dependent or alcohol-preferring rats. Therefore, this study was designed to determine whether this role for σ₁ receptors extends to ethanol-seeking behavior using an animal model of relapse and tested whether the suppressant effect of a potent σ₁ receptor antagonist, BD1047, generalizes to natural reward-seeking behavior. Two separate groups of rats were trained to orally self-administer 10% (w/v) ethanol or a highly palatable reinforcer, 3%/0.125% (w/v) glucose/saccharin (SuperSac), in the presence of a discriminative stimulus (S). Following extinction, during which the reinforcers and S were withheld, the presentation of the ethanol or SuperSac S produced comparable recovery of responding. BD1047 (1-20 mg/kg) exerted similar behavioral effects on both ethanol S-induced and SuperSac S-induced reinstatement, with the prevention of conditioned reinstatement only at the highest BD1047 dose. The present results show that σ₁ receptor blockade under the present conditions exerts similar effects on conditioned reinstatement induced by ethanol-related and SuperSac-related stimuli, suggestive of overlapping neural mechanisms that control ethanol and natural reward seeking.
Paternain, A V; Morales, M; Lerma, J
Although both protein and mRNAs for kainate receptor subunits are abundant in several brain regions, the responsiveness of AMPA receptors to kainate has made it difficult to demonstrate the presence of functional kainate-type receptors in native cells. Recently, however, we have shown that many hippocampal neurons in culture express glutamate receptors of the kainate type. The large nondesensitizing response that kainate induces at AMPA receptors precludes detection and analysis of smaller, rapidly desensitizing currents induced by kainate at kainate receptors. Consequently, the functional significance of these strongly desensitizing glutamate receptors remains enigmatic. We report here that the family of new noncompetitive antagonists of AMPA receptors (GYKI 52466 and 53655) minimally affects kainate-induced responses at kainate receptors while completely blocking AMPA receptor-mediated currents, making it possible to separate the responses mediated by each receptor. These compounds will allow determination of the role played by kainate receptors in synaptic transmission and plasticity in the mammalian brain, as well as evaluation of their involvement in neurotoxicity.
Nociceptive tolerance is improved by bradykinin receptor B1 antagonism and joint morphology is protected by both endothelin type A and bradykinin receptor B1 antagonism in a surgical model of osteoarthritis
Introduction Endothelin-1, a vasoconstrictor peptide, influences cartilage metabolism mainly via endothelin receptor type A (ETA). Along with the inflammatory nonapeptide vasodilator bradykinin (BK), which acts via bradykinin receptor B1 (BKB1) in chronic inflammatory conditions, these vasoactive factors potentiate joint pain and inflammation. We describe a preclinical study of the efficacy of treatment of surgically induced osteoarthritis with ETA and/or BKB1 specific peptide antagonists. We hypothesize that antagonism of both receptors will diminish osteoarthritis progress and articular nociception in a synergistic manner. Methods Osteoarthritis was surgically induced in male rats by transection of the right anterior cruciate ligament. Animals were subsequently treated with weekly intra-articular injections of specific peptide antagonists of ETA and/or BKB1. Hind limb nociception was measured by static weight bearing biweekly for two months post-operatively. Post-mortem, right knee joints were analyzed radiologically by X-ray and magnetic resonance, and histologically by the OARSI histopathology assessment system. Results Single local BKB1 antagonist treatment diminished overall hind limb nociception, and accelerated post-operative recovery after disease induction. Both ETA and/or BKB1 antagonist treatments protected joint radiomorphology and histomorphology. Dual ETA/BKB1 antagonism was slightly more protective, as measured by radiology and histology. Conclusions BKB1 antagonism improves nociceptive tolerance, and both ETA and/or BKB1 antagonism prevents joint cartilage degradation in a surgical model of osteoarthritis. Therefore, they represent a novel therapeutic strategy: specific receptor antagonism may prove beneficial in disease management. PMID:21575197
Li, Aihua; Hindmarch, Charles C T; Nattie, Eugene E; Paton, Julian F R
In normal rats, central administration of orexin or exposure to certain forms of stress can induce significant increases in blood pressure and sympathetic nerve activity, which can be blocked by orexin receptor antagonists. The resting blood pressure is, however, unaffected by such antagonists, but is significantly lower in rodents with total loss of orexin, such as prepro-orexin knockout mice and orexin neuron-ablated orexin/ataxin-3 transgenic rats. We hypothesize that orexin is involved in the pathophysiology and maintenance of high blood pressure in the spontaneously hypertensive rat (SHR), a model of primary hypertension. To test this hypothesis, we measured orexin-A mRNA expression in the rostral ventrolateral medulla and antagonized both orexin receptors using an orally administered potent dual orexin receptor antagonist, almorexant, in SHRs and normotensive Wistar–Kyoto rats. In SHRs, there was a strong trend towards an increased orexin-A mRNA expression in the rostral ventrolateral medulla, and blocking orexin receptors markedly lowered blood pressure (from 182/152 ± 5/6 to 149/119 ± 9/8 mmHg; P < 0.001), heart rate (P < 0.001), sympathetic vasomotor tone (P < 0.001) and the noradrenaline levels in cerebrospinal fluid and plasma (P < 0.002). The significant antihypertensive effects of almorexant were observed in wakefulness and non-rapid eye movement sleep during both dark and light phases of the diurnal cycle only in SHRs. Blocking orexin receptors had no effect on blood pressure and sympathetic tone in normotensive Wistar–Kyoto rats. Our study links the orexin system to the pathogenesis of high blood pressure in SHRs and suggests that modulation of the orexin system could be a potential target in treating some forms of hypertension. PMID:23671161
Voss, Bryan M.; Pavliv, Leo; de Caestecker, Mark; Hemnes, Anna R.; Carrier, Erica J.
Abstract Right ventricular (RV) failure is the primary cause of death in pulmonary arterial hypertension (PAH) and is a significant cause of morbidity and mortality in other forms of pulmonary hypertension. There are no approved therapies directed at preserving RV function. F-series and E-series isoprostanes are increased in heart failure and PAH, correlate to the severity of disease, and can signal through the thromboxane-prostanoid (TP) receptor, with effects from vasoconstriction to fibrosis. The goal of these studies was to determine whether blockade of the TP receptor with the antagonist CPI211 was beneficial therapeutically in PAH-induced RV dysfunction. Mice with RV dysfunction due to pressure overload by pulmonary artery banding (PAB) were given vehicle or CPI211. Two weeks after PAB, CPI211-treated mice were protected from fibrosis with pressure overload. Gene expression arrays and immunoblotting, quantitative histology and morphometry, and flow cytometric analysis were used to determine the mechanism of CPI211 protection. TP receptor inhibition caused a near normalization of fibrotic area, prevented cellular hypertrophy while allowing increased RV mass, increased expression of antifibrotic thrombospondin-4, and blocked induction of the profibrotic transforming growth factor β (TGF-β) pathway. A thromboxane synthase inhibitor or low-dose aspirin failed to replicate these results, which suggests that a ligand other than thromboxane mediates fibrosis through the TP receptor after pressure overload. This study suggests that TP receptor antagonism may improve RV adaptation in situations of pressure overload by decreasing fibrosis and TGF-β signaling. PMID:27252848
Lenda, Fatimazohra; Crouzin, Nadine; Cavalier, Mélanie; Guiramand, Janique; Lanté, Fabien; Barbanel, Gérard; Cohen-Solal, Catherine; Martinez, Jean; Guenoun, Farhate; Lamaty, Frédéric; Vignes, Michel
Five derivatives of 2-amino-adipic acid bearing a tetrazole-substituted in C5 position were synthesized. These compounds displayed selective antagonism towards N-methyl-D: -aspartate (NMDA) receptors compared with AMPA receptors, and they were devoid of any neurotoxicity. Among these five analogues, one exhibited a higher affinity for synaptic NMDA responses than the other four. Therefore, C5 tetrazole-substituted of 2-amino-adipic acid represent an interesting series of new NMDA receptor antagonists. This approach may be considered as a new strategy to develop ligands specifically targeted to synaptic or extra-synaptic NMDA receptors.
Hwang, Moon-Hyon; Yoo, Jeung-Ki; Luttrell, Meredith; Kim, Han-Kyul; Meade, Thomas H.; English, Mark; Talcott, Susanne; Jaffe, Iris Z.; Christou, Demetra D.
Mineralocorticoid receptor (MR) activation by aldosterone may regulate vascular function in health or contribute to vascular dysfunction in cardiovascular disease. Whether the effects are beneficial or detrimental to vascular function appear to be dependent on the integrity of the vascular endothelium and whether the responses are short-term or chronic. Acute modulation of MR activation has resulted in conflicting outcomes on vascular function in young healthy adults. Little is known about the vascular role of aldosterone and MR activation in healthy human aging. The primary objective of this study was to examine whether acute inhibition of MR by the selective antagonist eplerenone, influences vascular function in healthy older adults. We performed a randomized, double-blind, placebo-controlled crossover study in 22 adults (61±1 y; mean ± SE, 53–79 y) who were free from overt clinical cardiovascular disease. We measured brachial artery flow-mediated endothelium-dependent dilation and endothelium-independent dilation to sublingual nitroglycerin (0.4mg) following eplerenone (100 mg/dose, 2 doses, 24 hours between doses) or placebo. In response to acute MR antagonism, flow-mediated dilation decreased by 19% (from 6.9±0.5 to 5.6±0.6 %, P=0.02; placebo vs. eplerenone). Endothelial nitric oxide synthase (eNOS) activity also decreased following MR antagonism based on the ratio of phosphorylated eNOSSer1177 to total eNOS (1.53±0.08 vs. 1.29±0.06, P=0.02). Nitroglycerin-induced dilation and blood pressure were unaffected (nitroglycerin-induced dilation: 21.9±1.9 vs. 21.0±1.5 %, P=0.5 and systolic/diastolic blood pressure: 135/77±4/2 vs. 134/77± 4/2 mmHg, P ≥0.6). In conclusion, acute MR antagonism impairs vascular endothelial function in healthy older adults without influencing vascular smooth muscle responsiveness to exogenous nitric oxide or blood pressure. PMID:26639352
Hwang, Moon-Hyon; Yoo, Jeung-Ki; Luttrell, Meredith; Kim, Han-Kyul; Meade, Thomas H; English, Mark; Talcott, Susanne; Jaffe, Iris Z; Christou, Demetra D
Mineralocorticoid receptor (MR) activation by aldosterone may regulate vascular function in health or contribute to vascular dysfunction in cardiovascular disease. Whether the effects are beneficial or detrimental to vascular function appear to be dependent on the integrity of the vascular endothelium and whether the responses are short-term or chronic. Acute modulation of MR activation has resulted in conflicting outcomes on vascular function in young healthy adults. Little is known about the vascular role of aldosterone and MR activation in healthy human aging. The primary objective of this study was to examine whether acute inhibition of MR by the selective antagonist eplerenone, influences vascular function in healthy older adults. We performed a randomized, double-blind, placebo-controlled crossover study in 22 adults (61±1 years; mean±SE, 53-79 years) who were free from overt clinical cardiovascular disease. We measured brachial artery flow-mediated endothelium-dependent dilation and endothelium-independent dilation to sublingual nitroglycerin (0.4 mg) following eplerenone (100 mg/dose, 2 doses, 24h between doses) or placebo. In response to acute MR antagonism, flow-mediated dilation decreased by 19% (from 6.9±0.5 to 5.6±0.6%, P=0.02; placebo vs. eplerenone). Endothelial nitric oxide synthase (eNOS) activity also decreased following MR antagonism based on the ratio of phosphorylated eNOS(Ser1177) to total eNOS (1.53±0.08 vs. 1.29±0.06, P=0.02). Nitroglycerin-induced dilation and blood pressure were unaffected (nitroglycerin-induced dilation: 21.9±1.9 vs. 21.0±1.5%, P=0.5 and systolic/diastolic blood pressure: 135/77±4/2 vs. 134/77±4/2 mmHg, P≥0.6). In conclusion, acute MR antagonism impairs vascular endothelial function in healthy older adults without influencing vascular smooth muscle responsiveness to exogenous nitric oxide or blood pressure.
Schank, J.R.; Nelson, B.S.; Damadzic, R.; Tapocik, J.D.; Yao, M.; King, C.E.; Rowe, K.E.; Cheng, K.; Rice, K.C.; Heilig, M.
Substance P (SP) and its cognate neurokinin-1 receptor (NK1R) are involved in alcohol-related behaviors. We have previously reported that NK1R antagonism attenuates stress-induced reinstatement of alcohol seeking and suppresses escalated alcohol self-administration, but does not affect primary reinforcement or cue-induced reinstatement. Here, we administered an NK1R antagonist or vehicle prior to footshock-induced reinstatement of alcohol seeking, and mapped the resulting neuronal activation using Fos immunohistochemistry. As expected, vehicle treated animals exposed to footshock showed induction of Fos immunoreactivity in several regions of the brain stress circuitry, including the amygdala (AMG), nucleus accumbens (NAC), dorsal raphe nucleus (DR), prefrontal cortex (PFC), and bed nucleus of the stria terminalis (BNST). NK1R antagonism selectively suppressed the stress-induced increase in Fos in the DR and NAC shell. In the DR, Fos-induction by stress largely overlapped with tryptophan hydroxylase (TrpH), indicating activation of serotonergic neurons. Of NAC shell neurons activated during stress-induced reinstatement of alcohol seeking, about 30% co-expressed dynorphin (DYN), while 70% co-expressed enkephalin (ENK). Few (<1%) activated NAC shell neurons co-expressed choline acetyltransferase (ChAT), which labels the cholinergic interneurons of this region. Infusion of the NK1R antagonist L822429 into the NAC shell blocked stress-induced reinstatement of alcohol seeking. In contrast, L822429 infusion into the DR had no effect, suggesting that the influence of NK1R signaling on neuronal activity in the DR is indirect. Taken together, our results outline a potential pathway through which endogenous NK1R activation mediates stress-induced alcohol seeking. PMID:26188146
Singhal, Hari; Greene, Marianne E.; Tarulli, Gerard; Zarnke, Allison L.; Bourgo, Ryan J.; Laine, Muriel; Chang, Ya-Fang; Ma, Shihong; Dembo, Anna G.; Raj, Ganesh V.; Hickey, Theresa E.; Tilley, Wayne D.; Greene, Geoffrey L.
The functional role of progesterone receptor (PR) and its impact on estrogen signaling in breast cancer remain controversial. In primary ER+ (estrogen receptor–positive)/PR+ human tumors, we report that PR reprograms estrogen signaling as a genomic agonist and a phenotypic antagonist. In isolation, estrogen and progestin act as genomic agonists by regulating the expression of common target genes in similar directions, but at different levels. Similarly, in isolation, progestin is also a weak phenotypic agonist of estrogen action. However, in the presence of both hormones, progestin behaves as a phenotypic estrogen antagonist. PR remodels nucleosomes to noncompetitively redirect ER genomic binding to distal enhancers enriched for BRCA1 binding motifs and sites that link PR and ER/PR complexes. When both hormones are present, progestin modulates estrogen action, such that responsive transcriptomes, cellular processes, and ER/PR recruitment to genomic sites correlate with those observed with PR alone, but not ER alone. Despite this overall correlation, the transcriptome patterns modulated by dual treatment are sufficiently different from individual treatments, such that antagonism of oncogenic processes is both predicted and observed. Combination therapies using the selective PR modulator/antagonist (SPRM) CDB4124 in combination with tamoxifen elicited 70% cytotoxic tumor regression of T47D tumor xenografts, whereas individual therapies inhibited tumor growth without net regression. Our findings demonstrate that PR redirects ER chromatin binding to antagonize estrogen signaling and that SPRMs can potentiate responses to antiestrogens, suggesting that cotargeting of ER and PR in ER+/PR+ breast cancers should be explored. PMID:27386569
Buxton, I.L.O.; Bowen, S.M.
Incubation of intact cardiomyocytes with the histamine antagonist (/sup 3/H)mepyramine results in rapid reversible binding to a single class of high affinity sites (K/sub D/ = 1.2nM; 50,000 sites/myocyte). In membranes from purified myocytes histamine competition of (/sup 3/H)mepyramine binding (K/sub D/ = 300nM) is not altered by GTP (10..mu..M). Competition of (/sup 3/H)mepyramine binding by H-receptor subtype-selective antagonists suggests the presence of a single class of H/sub 1/-receptors. Incubation of intact myocytes with histamine (luM, H/sub 1/ receptor activation) plus norepinephrine (NE 1uM, alpha/sub 1/ + beta/sub 1/ receptor activation) for 3 min leads to significantly more cAMP accumulation (36.5 pmol/10/sup 6/ myocytes) than NE alone (30 pmol/10/sup 6/ myocytes). Histamine alone does not alter basal cAMP = 10.4 pmol/10/sup 6/ myocytes, or beta/sub 1/ stimulation (isoproternol, 1uM) = 39.6 pmol/10/sup 6/ myocytes. Cyclic AMP accumulation with NE plus prazosin 10nM, (alpha/sub 1/ + beta/sub 1/ + alpha/sub 1/ blockade) is indistinguishable from NE + histamine, (alpha/sub 1/ + beta/sub 1/ + H/sub 1/) stimulation. Histamine competition for (/sup 3/H)prazosin binding suggests that histamine does not block alpha/sub 1/ receptors on the myocyte. These data suggest that H/sub 1/ receptor activation leads to antagonism of the alpha/sub 1/ receptor mediated activation of cAMP phosphodiesterase the authors have recently described.
Robinson, Prema; Taffet, George E.; Engineer, Nikita; Khumbatta, Mitra; Firozgary, Bahrom; Reynolds, Corey; Pham, Thuy; Bulsara, Tushar; Firozgary, Gohar
Viral-myocarditis is an important cause of heart failure for which no specific treatment is available. We previously showed the neuropeptide substance P (SP) is associated with the pathogenesis of murine myocarditis caused by encephalomyocarditis virus (EMCV). The current studies determined if pharmacological inhibition of SP-signaling via its high affinity receptor, NK1R and downstream G-protein, Ras homolog gene family, member-A (RhoA), will be beneficial in viral-myocarditis. Aprepitant (1.2 mg/kg), a SP-receptor antagonist, or fasudil (10 mg/kg), a RhoA inhibitor, or saline control was administered daily to mice orally for 3 days, prior to, or 5 days following, intraperitoneal infection with and without 50 PFU of EMCV, following which disease assessment studies, including echocardiogram and cardiac Doppler were performed in day 14 after infection. Pretreatment and posttreatment with aprepitant significantly reduced mortality, heart and cardiomyocyte size, and cardiac viral RNA levels (P < 0.05 all, ANOVA). Only aprepitant pretreatment improved heart functions; it significantly decreased end systolic diameter, improved fractional shortening, and increased peak aortic flow velocity (P < 0.05 all, ANOVA). Pre- or posttreatment with fasudil did not significantly impact disease manifestations. These findings indicate that SP contributes to cardiac-remodeling and dysfunction following ECMV infection via its high affinity receptor, but not through the Rho-A pathway. These studies suggest that SP-receptor antagonism may be a novel therapeutic-option for patients with viral-myocarditis. PMID:25821814
Schmeichel, Brooke E; Barbier, Estelle; Misra, Kaushik K; Contet, Candice; Schlosburg, Joel E; Grigoriadis, Dimitri; Williams, John P; Karlsson, Camilla; Pitcairn, Caleb; Heilig, Markus; Koob, George F; Vendruscolo, Leandro F
The hypocretin/orexin (HCRT) system has been associated with both positive and negative drug reinforcement, implicating HCRT receptor 1 (HCRT-R1) signaling in drug-related behaviors for all major drug classes, including opioids. However, to date there are limited studies investigating the role of HCRT receptor 2 (HCRT-R2) signaling in compulsive-like drug seeking. Escalation of drug intake with extended access has been suggested to model the transition from controlled drug use to compulsive-like drug seeking/taking. The current study examined the effects of a HCRT-R2 antagonist, NBI-80713, on heroin self-administration in rats allowed short- (1 h; ShA) or long- (12 h; LgA) access to intravenous heroin self-administration. Results indicate that systemically administered NBI-80713 dose-dependently decreased heroin self-administration in LgA, but not in ShA, animals. Quantitative PCR analyses showed an increase in Hcrtr2 mRNA levels in the central amygdala, a stress-related brain region, of LgA rats. These observations suggest a functional role for HCRT-R2 signaling in compulsive-like heroin self-administration associated with extended access and indicate HCRT-R2 antagonism as a potential pharmacological target for the treatment of heroin dependence.
Schmeichel, Brooke E; Barbier, Estelle; Misra, Kaushik K; Contet, Candice; Schlosburg, Joel E; Grigoriadis, Dimitri; Williams, John P; Karlsson, Camilla; Pitcairn, Caleb; Heilig, Markus; Koob, George F; Vendruscolo, Leandro F
The hypocretin/orexin (HCRT) system has been associated with both positive and negative drug reinforcement, implicating HCRT receptor 1 (HCRT-R1) signaling in drug-related behaviors for all major drug classes, including opioids. However, to date there are limited studies investigating the role of HCRT receptor 2 (HCRT-R2) signaling in compulsive-like drug seeking. Escalation of drug intake with extended access has been suggested to model the transition from controlled drug use to compulsive-like drug seeking/taking. The current study examined the effects of a HCRT-R2 antagonist, NBI-80713, on heroin self-administration in rats allowed short- (1 h; ShA) or long- (12 h; LgA) access to intravenous heroin self-administration. Results indicate that systemically administered NBI-80713 dose-dependently decreased heroin self-administration in LgA, but not in ShA, animals. Quantitative PCR analyses showed an increase in Hcrtr2 mRNA levels in the central amygdala, a stress-related brain region, of LgA rats. These observations suggest a functional role for HCRT-R2 signaling in compulsive-like heroin self-administration associated with extended access and indicate HCRT-R2 antagonism as a potential pharmacological target for the treatment of heroin dependence. PMID:25367502
Kalyvianaki, Konstantina; Gebhart, Veronika; Peroulis, Nikolaos; Panagiotopoulou, Christina; Kiagiadaki, Fotini; Pediaditakis, Iosif; Aivaliotis, Michalis; Moustou, Eleni; Tzardi, Maria; Notas, George; Castanas, Elias; Kampa, Marilena
Accumulating evidence during the last decades revealed that androgen can exert membrane initiated actions that involve signaling via specific kinases and the modulation of significant cellular processes, important for prostate cancer cell growth and metastasis. Results of the present work clearly show that androgens can specifically act at the membrane level via the GPCR oxoeicosanoid receptor 1 (OXER1) in prostate cancer cells. In fact, OXER1 expression parallels that of membrane androgen binding in prostate cancer cell lines and tumor specimens, while in silico docking simulation of OXER1 showed that testosterone could bind to OXER1 within the same grove as 5-OxoETE, the natural ligand of OXER1. Interestingly, testosterone antagonizes the effects of 5-oxoETE on specific signaling pathways and rapid effects such as actin cytoskeleton reorganization that ultimately can modulate cell migration and metastasis. These findings verify that membrane-acting androgens exert specific effects through an antagonistic interaction with OXER1. Additionally, this interaction between androgen and OXER1, which is an arachidonic acid metabolite receptor expressed in prostate cancer, provides a novel link between steroid and lipid actions and renders OXER1 as new player in the disease. These findings should be taken into account in the design of novel therapeutic approaches in prostate cancer. PMID:28290516
Wadenberg, M L; Ahlenius, S
It has been shown that the administration of 5-hydroxytryptamine (5-HT)1A receptor agonists will antagonize the catalepsy induced by dopamine D1 or D2 receptor blocking agents. In the present study, administration of the 5-HT2A/C receptor agonist, 1-(2,5-dimethoxy-4-iodo)-2-aminopropane (DOI) (1 mg kg-1 s.c.), counteracted the catalepsy produced by the dopamine D2 receptor antagonist, raclopride (16 mg kg-1 s.c.), but not by the dopamine D1 receptor antagonist (R)-(+)-8-chloro-2,3,4,5-tetra-hydro-3-methyl-5-phenyl-1H-3-benzazepine (SCH 23390) (0.2 mg kg-1 s.c.). The effects of DOI on raclopride-induced catalepsy were fully antagonized by pretreatment with the 5-HT2A/C receptor antagonist, ritanserin (2 mg kg-1 s.c.). The 5-HT precursor, 5-hydroxytryptophan (5-HTP) (6.25-25.0 mg kg-1 i.p.), in combination with the peripheral 5-HTP decarboxylase inhibitor, benserazide (25 mg kg-1 i.p.), and the selective serotonin reuptake inhibitor, zimeldine (10 mg kg-1 s.c.), enhanced the catalepsy produced by a low dose of raclopride (4 mg kg-1 s.c.). It is concluded that stimulation of (postsynaptic) 5-HT2 receptors results in antagonism of the catalepsy induced by treatment with a dopamine D2, but not a D1, receptor antagonist. The fact that 5-HTP, in the presence of benserazide and zimeldine, enhanced raclopride-induced catalepsy suggests the possibility of postsynaptic 5-HT receptors acting in opposition to the 5-HT1 and 5-HT2 receptors, as regards extrapyramidal motor functions in the rat.
Hughes, Tiffany; Briercheck, Edward L.; Freud, Aharon G.; Trotta, Rossana; McClory, Susan; Scoville, Steven D.; Keller, Karen; Deng, Youcai; Cole, Jordan; Harrison, Nicholas; Mao, Charlene; Zhang, Jianying; Benson, Don M.; Yu, Jianhua; Caligiuri, Michael A.
SUMMARY Accumulating evidence indicates that human natural killer (NK) cells develop in secondary lymphoid tissue (SLT) through a so-called “stage 3” developmental intermediate minimally characterized by a CD34-CD117+CD94- immunophenotype that lacks mature NK cell function. This stage 3 population is heterogeneous, potentially composed of functionally distinct innate lymphoid cell (ILC) types that includes interleukin-1 receptor (IL-1R1) positive, IL-22-producing ILC3s. Whether human ILC3s are developmentally related to NK cells is a subject of ongoing investigation. Here we show that antagonism of the aryl hydrocarbon receptor (AHR) or silencing of AHR gene expression promotes differentiation of tonsillar IL-22-producing IL-1R1hi human ILC3s to CD56brightCD94+ IFN-gamma-producing cytolytic mature NK cells expressing eomesodermin (EOMES) and T-Box Protein 21 (TBX21 or TBET). Hence, AHR is a transcription factor that prevents human IL-1R1hi ILC3s from differentiating into NK cells. PMID:24953655
Histamine H3 receptors are present as autoreceptors on histaminergic neurons and as heteroreceptors on nonhistaminergic neurones. They control the release and synthesis of histamine and several other key neurotransmitters in the brain. H3 antagonism may be a novel approach to develop a new class of antipsychotic medications given the gathering evidence reporting therapeutic efficacy in several central nervous system disorders. Several medications such as cariprazine, lurasidone, LY214002, bexarotene, rasagiline, raloxifene, BL-1020 and ITI-070 are being developed to treat the negative symptoms and cognitive impairments of schizophrenia. These medications works through diverse mechanisms which include agonism at metabotropic glutamate receptor (mGluR2/3), partial agonism at dopamine D2, D3 and serotonin 5-HT1A receptors, antagonism at D2, 5-HT2A, 5-HT2B and 5-HT7 receptors, combined dopamine antagonism with GABA agonist activity, inhibition of monoamine oxidase-B, modulation of oestrogen receptor, and activation of nuclear retinoid X receptor. However, still specific safe therapy for psychosis remains at large. Schizophrenia is a severe neuropsychiatric disorder result both from hyper- and hypo-dopaminergic transmission causing positive and negative symptoms, respectively. Pharmacological stimulation of dopamine release in the prefrontal cortex has been a viable approach in treating negative symptoms and cognitive deficits of schizophrenia symptoms that are currently not well treated and continue to represent significant unmet medical challenges. Administration of H3 antagonists/inverse agonists increase extracellular dopamine concentrations in rat prefrontal cortex, but not in the striatum suggesting that antagonism via H3 receptor may be a potential target for treating negative symptoms and cognitive deficits associated with schizophrenia. Further, insights are emerging into the potential role of histamine H3 receptors as a target of antiobesity therapeutics which
Smeets, R L; Joosten, L A B; Arntz, O J; Bennink, M B; Takahashi, N; Carlsen, H; Martin, M U; van den Berg, W B; van de Loo, F A J
To discern the mode of interleukin-1 (IL-1) inhibition of soluble IL-1 receptor accessory protein (sIL-1RAcP) by comparison with IL-1 receptor antagonist (IL-1Ra) in arthritis. Adenoviral vectors encoding either sIL-1RAcP or IL-1Ra were administered systemically before onset of collagen-induced arthritis in DBA/1 mice. Anti-bovine type II collagen IgG and IL-6 were quantified in serum. Proliferative response of splenic T cells was determined in the presence of sIL-1RAcP or IL-1Ra. The effect on IL-1 inhibition of recombinant sIL-1RAcP and IL-1Ra was further examined in vitro, using NF-kappaB luciferase reporter cell lines. Quantitative polymerase chain reaction was used to determine the relative messenger RNA expression of the IL-1 receptors. Adenoviral overexpression of both sIL-1RAcP and IL-1Ra resulted in amelioration of the collagen-induced arthritis. Both IL-1 antagonists reduced the circulating levels of antigen-specific IgG2a antibodies, but only IL-1Ra was able to inhibit lymphocyte proliferation. By using purified lymphocyte populations derived from NF-kappaB reporter mice, we showed that sIL-1RAcP inhibits IL-1-induced NF-kappaB activity in B cells but not T cells, whereas IL-1Ra inhibited IL-1 on both cell types. A study in a panel of NF-kappaB luciferase reporter cells showed that the sIL-1RAcP inhibits IL-1 signaling on cells expressing either low levels of membrane IL-1RAcP or high levels of IL-1RII. We show that the sIL-1RAcP ameliorated experimental arthritis without affecting T cell immunity, in contrast to IL-1Ra. Our results provide data in support of receptor competition by sIL-1RAcP as an explanation for the different mode of IL-1 antagonism in comparison with IL-1Ra.
Ferraris, Jimena; Boutillon, Florence; Bernadet, Marie; Seilicovich, Adriana; Goffin, Vincent; Pisera, Daniel
Since anterior pituitary expresses prolactin receptors, prolactin secreted by lactotropes could exert autocrine or paracrine actions on anterior pituitary cells. In fact, it has been observed that prolactin inhibits its own expression by lactotropes. Our hypothesis is that prolactin participates in the control of anterior pituitary cell turnover. In the present study, we explored the action of prolactin on proliferation and apoptosis of anterior pituitary cells and its effect on the expression of the prolactin receptor. To determine the activity of endogenous prolactin, we evaluated the effect of the competitive prolactin receptor antagonist Δ1-9-G129R-hPRL in vivo, using transgenic mice that constitutively and systemically express this antagonist. The weight of the pituitary gland and the anterior pituitary proliferation index, determined by BrdU incorporation, were higher in transgenic mice expressing the antagonist than in wild-type littermates. In addition, blockade of prolactin receptor in vitro by Δ1-9-G129R-hPRL increased proliferation and inhibited apoptosis of somatolactotrope GH3 cells and of primary cultures of male rat anterior pituitary cells, including lactotropes. These results suggest that prolactin acts as an autocrine/paracrine antiproliferative and proapoptotic factor in the anterior pituitary gland. In addition, anterior pituitary expression of the long isoform of the prolactin receptor, measured by real-time PCR, increased about 10-fold in transgenic mice expressing the prolactin receptor antagonist, whereas only a modest increase in the S3 short-isoform expression was observed. These results suggest that endogenous prolactin may regulate its own biological actions in the anterior pituitary by inhibiting the expression of the long isoform of the prolactin receptor. In conclusion, our observations suggest that prolactin is involved in the maintenance of physiological cell renewal in the anterior pituitary. Alterations in this physiological
Palomo, Jennifer; Dietrich, Damien; Martin, Praxedis; Palmer, Gaby; Gabay, Cem
The interleukin (IL)-1 family of cytokines comprises 11 members, including 7 pro-inflammatory agonists (IL-1α, IL-1β, IL-18, IL-33, IL-36α, IL-36β, IL-36γ) and 4 defined or putative antagonists (IL-1R antagonist (IL-1Ra), IL-36Ra, IL-37, and IL-38) exerting anti-inflammatory activities. Except for IL-1Ra, IL-1 cytokines do not possess a leader sequence and are secreted via an unconventional pathway. In addition, IL-1β and IL-18 are produced as biologically inert pro-peptides that require cleavage by caspase-1 in their N-terminal region to generate active proteins. N-terminal processing is also required for full activity of IL-36 cytokines. The IL-1 receptor (IL-1R) family comprises 10 members and includes cytokine-specific receptors, co-receptors and inhibitory receptors. The signaling IL-1Rs share a common structure with three extracellular immunoglobulin (Ig) domains and an intracellular Toll-like/IL-1R (TIR) domain. IL-1 cytokines bind to their specific receptor, which leads to the recruitment of a co-receptor and intracellular signaling. IL-1 cytokines induce potent inflammatory responses and their activity is tightly controlled at the level of production, protein processing and maturation, receptor binding and post-receptor signaling by naturally occurring inhibitors. Some of these inhibitors are IL-1 family antagonists, while others are IL-1R family members acting as membrane-bound or soluble decoy receptors. An imbalance between agonist and antagonist levels can lead to exaggerated inflammatory responses. Several genetic modifications or mutations associated with dysregulated IL-1 activity and autoinflammatory disorders were identified in mouse models and in patients. These findings paved the road to the successful use of IL-1 inhibitors in diseases that were previously considered as untreatable. Copyright © 2015 Elsevier Ltd. All rights reserved.
Vendruscolo, Leandro F.; Estey, David; Goodell, Vivian; Macshane, Lauren G.; Logrip, Marian L.; Schlosburg, Joel E.; McGinn, M. Adrienne; Zamora-Martinez, Eva R.; Belanoff, Joseph K.; Hunt, Hazel J.; Sanna, Pietro P.; George, Olivier; Koob, George F.; Edwards, Scott; Mason, Barbara J.
Alcoholism, or alcohol use disorder, is a major public health concern that is a considerable risk factor for morbidity and disability; therefore, effective treatments are urgently needed. Here, we demonstrated that the glucocorticoid receptor (GR) antagonist mifepristone reduces alcohol intake in alcohol-dependent rats but not in nondependent animals. Both systemic delivery and direct administration into the central nucleus of the amygdala, a critical stress-related brain region, were sufficient to reduce alcohol consumption in dependent animals. We also tested the use of mifepristone in 56 alcohol-dependent human subjects as part of a double-blind clinical and laboratory-based study. Relative to placebo, individuals who received mifepristone (600 mg daily taken orally for 1 week) exhibited a substantial reduction in alcohol-cued craving in the laboratory, and naturalistic measures revealed reduced alcohol consumption during the 1-week treatment phase and 1-week post-treatment phase in mifepristone-treated individuals. Mifepristone was well tolerated and improved liver-function markers. Together, these results support further exploration of GR antagonism via mifepristone as a therapeutic strategy for alcoholism. PMID:26121746
Fronz, Ulrike; Deten, Alexander; Baumann, Frank; Kranz, Alexander; Weidlich, Sarah; Härtig, Wolfgang; Nieber, Karen; Boltze, Johannes; Wagner, Daniel-Christoph
Antagonism of the adenosine A2A receptor (A2AR) has been shown to elicit substantial neuroprotective properties when given immediately after cerebral ischemia. We asked whether the continuous application of a selective A2AR antagonist within a clinically relevant time window will be a feasible and effective approach to treat focal cerebral ischemia. To answer this question, we subjected 20 male spontaneously hypertensive rats to permanent middle cerebral artery occlusion and randomized them equally to a verum and a control group. Two hours after stroke onset, the animals received a subcutaneous implantation of an osmotic minipump filled with 5 mg kg(-1) day(-1) 8-(3-chlorostyryl) caffeine (CSC) or vehicle solution. The serum level of CSC was measured twice a day for three consecutive days. The infarct volume was determined at days 1 and 3 using magnetic resonance imaging. We found the serum level of CSC showing a bell-shaped curve with its maximum at 36 h. The infarct volume was not affected by continuous CSC treatment. These results suggest that delayed and continuous CSC application was not sufficient to treat acute ischemic stroke, potentially due to unfavorable hepatic elimination and metabolization of the pharmaceutical.
Dias, James A.; Bonnet, Béatrice; Weaver, Barbara A.; Watts, Julie; Kluetzman, Kerri; Thomas, Richard M.; Poli, Sonia; Mutel, Vincent; Campo, Brice
High quality gamete production in males and females requires the pituitary gonadotropin follicle stimulating hormone (FSH). In this report a novel chemical class of small molecule inhibitors of FSH receptor (FSHR) is described. ADX61623, a negative allosteric modulator (NAM), increased the affinity of interaction between 125I-hFSH and human FSHR (hFSHR) five fold. This form of FSHR occupied simultaneously by FSH and ADX61623 was inactive for cAMP and progesterone production in primary cultures of rat granulosa cells. In contrast, ADX61623 did not block estrogen production. This demonstrates for the first time, biased antagonism at the FSHR. To determine if ADX61623 blocked FSH induction of follicle development in vivo, a bioassay to measure follicular development and oocyte production in immature female rats was validated. ADX61623 was not completely effective in blocking FSH induced follicular development in vivo at doses up to 100 mg/kg as oocyte production and ovarian weight gain were only moderately reduced. These data illustrate that FSHR couples to multiple signaling pathways in vivo. Suppression of one pool of FSHR uncouples Gαs and cAMP production, and decreases progesterone production. Occupancy of another pool of FSHR sensitizes granulosa cells to FSH induced estradiol production. Therefore, ADX61623 is a useful tool to investigate further the mechanism of the FSHR signaling dichotomy. This may lead to a greater understanding of the signaling infrastructure which enables estrogen biosynthesis and may prove useful in treating estrogen dependent disease. PMID:21184806
Sucharov, Carmen C; Hijmans, Jamie G; Sobus, Rebecca D; Melhado, William F A; Miyamoto, Shelley D; Stauffer, Brian L
Children with heart failure are treated with similar medical therapy as adults with heart failure. In contrast to adults with heart failure, these treatment regiments are not associated with improved outcomes in children. Recent studies have demonstrated age-related pathophysiological differences in the molecular mechanisms of heart failure between children and adults. There are no animal models of pediatric cardiomyopathy to allow mechanistic studies. The purpose of the current experiments was to develop a mouse model of pediatric heart disease and test whether the influence of β-adrenergic receptor (β-AR) antagonism could be modeled in this system. We hypothesized that isoproterenol treatment of young mice would provide a model system of cardiac pathology, and that nonselective β-AR blockade would provide benefit in adult, but not young, mice, similar to clinical trial data. We found that isoproterenol treatment (through osmotic minipump implantation) of young and adult mice produced similar degrees of cardiac hypertrophy and recapitulated several age-related molecular abnormalities in human heart failure, including phospholamban phosphorylation and β-AR expression. We also found that nonselective β-AR blockade effectively prevented pathological cardiac growth and collagen expression in the adult but not young mice, and that selective β1-AR blockade was effective in both young and adult isoproterenol-treated mice. In conclusion, we have developed the first model system for β-AR-mediated pediatric heart disease. Furthermore, we have generated novel data suggesting beneficial effects of selective β1-AR blockade in the pediatric heart.
Nicholas, Sally A; Oniku, Abraham E; Sumbayev, Vadim V
Programmed cell death or apoptosis is an important part of the host innate immune defence, especially against ssRNA viruses (influenza virus, HIV-1, ebola virus, hepatitis C virus and many others). Viral ssRNA is recognised by endosomal Toll-like receptors 7 and 8 (TLR7/8) which induce further stages of immune defence against these pathogens. Some of the immune cells die because of inflammatory stress allowing for the selection of those cells which are resistant to stress-induced apoptosis and which are used in further stages of the host immune response. On the other hand, apoptosis could be used as an instrument to suppress the function of activated inflammatory cells. However, the mechanisms underlying death of the inflammatory cells associated with stress induced by ligands of TLR7/8 remain unclear. In this study we have found that programmed death of human myeloid cells from different cell lines associated with ligand-induced TLR7/8-mediated inflammatory stress depends on activation of apoptosis signal-regulating kinase 1 (ASK1). This enzyme is, however, not required for the production of pro-inflammatory cytokines - TNF-α and IL-1β. We have found that released IL-1β and TNF-α are involved in apoptosis of myeloid cells associated with TLR7/8-mediated inflammatory stress. The pro-apoptotic effect of released TNF-α in this case is much lower compared to that of IL-1β.
Ågerstam, Helena; Karlsson, Christine; Hansen, Nils; Sandén, Carl; Askmyr, Maria; von Palffy, Sofia; Högberg, Carl; Rissler, Marianne; Wunderlich, Mark; Juliusson, Gunnar; Richter, Johan; Sjöström, Kjell; Bhatia, Ravi; Mulloy, James C.; Järås, Marcus; Fioretos, Thoas
Acute myeloid leukemia (AML) is associated with a poor survival rate, and there is an urgent need for novel and more efficient therapies, ideally targeting AML stem cells that are essential for maintaining the disease. The interleukin 1 receptor accessory protein (IL1RAP; IL1R3) is expressed on candidate leukemic stem cells in the majority of AML patients, but not on normal hematopoietic stem cells. We show here that monoclonal antibodies targeting IL1RAP have strong antileukemic effects in xenograft models of human AML. We demonstrate that effector-cell–mediated killing is essential for the observed therapeutic effects and that natural killer cells constitute a critical human effector cell type. Because IL-1 signaling is important for the growth of AML cells, we generated an IL1RAP-targeting antibody capable of blocking IL-1 signaling and show that this antibody suppresses the proliferation of primary human AML cells. Hence, IL1RAP can be efficiently targeted with an anti-IL1RAP antibody capable of both achieving antibody-dependent cellular cytotoxicity and blocking of IL-1 signaling as modes of action. Collectively, these results provide important evidence in support of IL1RAP as a target for antibody-based treatment of AML. PMID:26261316
Ågerstam, Helena; Karlsson, Christine; Hansen, Nils; Sandén, Carl; Askmyr, Maria; von Palffy, Sofia; Högberg, Carl; Rissler, Marianne; Wunderlich, Mark; Juliusson, Gunnar; Richter, Johan; Sjöström, Kjell; Bhatia, Ravi; Mulloy, James C; Järås, Marcus; Fioretos, Thoas
Acute myeloid leukemia (AML) is associated with a poor survival rate, and there is an urgent need for novel and more efficient therapies, ideally targeting AML stem cells that are essential for maintaining the disease. The interleukin 1 receptor accessory protein (IL1RAP; IL1R3) is expressed on candidate leukemic stem cells in the majority of AML patients, but not on normal hematopoietic stem cells. We show here that monoclonal antibodies targeting IL1RAP have strong antileukemic effects in xenograft models of human AML. We demonstrate that effector-cell-mediated killing is essential for the observed therapeutic effects and that natural killer cells constitute a critical human effector cell type. Because IL-1 signaling is important for the growth of AML cells, we generated an IL1RAP-targeting antibody capable of blocking IL-1 signaling and show that this antibody suppresses the proliferation of primary human AML cells. Hence, IL1RAP can be efficiently targeted with an anti-IL1RAP antibody capable of both achieving antibody-dependent cellular cytotoxicity and blocking of IL-1 signaling as modes of action. Collectively, these results provide important evidence in support of IL1RAP as a target for antibody-based treatment of AML.
Ren, Xiaoming; Gelinas, Amy D; von Carlowitz, Ira; Janjic, Nebojsa; Pyle, Anna Marie
IL-1α is an essential cytokine that contributes to inflammatory responses and is implicated in various forms of pathogenesis and cancer. Here we report a naphthyl modified DNA aptamer that specifically binds IL-1α and inhibits its signaling pathway. By solving the crystal structure of the IL-1α/aptamer, we provide a high-resolution structure of this critical cytokine and we reveal its functional interaction interface with high-affinity ligands. The non-helical aptamer, which represents a highly compact nucleic acid structure, contains a wealth of new conformational features, including an unknown form of G-quadruplex. The IL-1α/aptamer interface is composed of unusual polar and hydrophobic elements, along with an elaborate hydrogen bonding network that is mediated by sodium ion. IL-1α uses the same interface to interact with both the aptamer and its cognate receptor IL-1RI, thereby suggesting a novel route to immunomodulatory therapeutics.The cytokine interleukin 1α (IL-1α) plays an important role in inflammatory processes. Here the authors use SELEX to generate a modified DNA aptamer which specifically binds IL-1α, present the structure of the IL-1α/aptamer complex and show that this aptamer inhibits the IL-1α signaling pathway.
Brown, Geoffrey; Marchwicka, Aleksandra; Cunningham, Alan; Toellner, Kai-Michael; Marcinkowska, Ewa
Activities of the retinoic acid receptor (RAR)α and RARγ are important to hematopoiesis. Here, we have investigated the effects of receptor selective agonists and antagonists on the primitive human hematopoietic cell lines KG1 and NB-4 and purified normal human hematopoietic stem cells (HSCs). Agonizing RARα (by AGN195183) was effective in driving neutrophil differentiation of NB-4 cells and this agonist synergized with a low amount (10 nM) of 1α,25-dihydroxyvitamin D3 to drive monocyte differentiation of NB-4 and KG1 cells. Treatment of cultures of human HSCs (supplemented with stem cell factor ± interleukin 3) with an antagonist of all RARs (AGN194310) or of RARα (AGN196996) prolonged the lifespan of cultures, up to 55 days, and increased the production of neutrophils and monocytes. Slowing down of cell differentiation was not observed, and instead, hematopoietic stem and progenitor cells had expanded in number. Antagonism of RARγ (by AGN205728) did not affect cultures of HSCs. Studies of CV-1 and LNCaP cells transfected with RAR expression vectors and a reporter vector revealed that RARγ and RARβ are activated by sub-nM all-trans retinoic acid (EC50-0.3 nM): ~50-fold more is required for activation of RARα (EC50-16 nM). These findings further support the notion that the balance of expression and activity of RARα and RARγ are important to hematopoietic stem and progenitor cell expansion and differentiation.
Smith, Kayla J; Murray, Iain A; Tanos, Rachel; Tellew, John; Boitano, Anthony E; Bisson, William H; Kolluri, Siva K; Cooke, Michael P; Perdew, Gary H
The biological functions of the aryl hydrocarbon receptor (AHR) can be delineated into dioxin response element (DRE)-dependent or -independent activities. Ligands exhibiting either full or partial agonist activity, e.g., 2,3,7,8-tetrachlorodibenzo-p-dioxin and α-naphthoflavone, have been demonstrated to potentiate both DRE-dependent and -independent AHR function. In contrast, the recently identified selective AHR modulators (SAhRMs), e.g., 1-allyl-3-(3,4-dimethoxyphenyl)-7-(trifluoromethyl)-1H-indazole (SGA360), bias AHR toward DRE-independent functionality while displaying antagonism with regard to ligand-induced DRE-dependent transcription. Recent studies have expanded the physiological role of AHR to include modulation of hematopoietic progenitor expansion and immunoregulation. It remains to be established whether such physiological roles are mediated through DRE-dependent or -independent pathways. Here, we present evidence for a third class of AHR ligand, "pure" or complete antagonists with the capacity to suppress both DRE-dependent and -independent AHR functions, which may facilitate dissection of physiological AHR function with regard to DRE or non-DRE-mediated signaling. Competitive ligand binding assays together with in silico modeling identify N-(2-(1H-indol-3-yl)ethyl)-9-isopropyl-2-(5-methylpyridin-3-yl)-9H-purin-6-amine (GNF351) as a high-affinity AHR ligand. DRE-dependent reporter assays, in conjunction with quantitative polymerase chain reaction analysis of AHR targets, reveal GNF351 as a potent AHR antagonist that demonstrates efficacy in the nanomolar range. Furthermore, unlike many currently used AHR antagonists, e.g., α-naphthoflavone, GNF351 is devoid of partial agonist potential. It is noteworthy that in a model of AHR-mediated DRE-independent function, i.e., suppression of cytokine-induced acute-phase gene expression, GNF351 has the capacity to antagonize agonist and SAhRM-mediated suppression of SAA1. Such data indicate that GNF351 is a
In vivo administration of extracellular cGMP normalizes TNF-α and membrane expression of AMPA receptors in hippocampus and spatial reference memory but not IL-1β, NMDA receptors in membrane and working memory in hyperammonemic rats.
Cabrera-Pastor, Andrea; Hernandez-Rabaza, Vicente; Taoro-Gonzalez, Lucas; Balzano, Tiziano; Llansola, Marta; Felipo, Vicente
Patients with hepatic encephalopathy (HE) show working memory and visuo-spatial orientation deficits. Hyperammonemia is a main contributor to cognitive impairment in HE. Hyperammonemic rats show impaired spatial learning and learning ability in the Y maze. Intracerebral administration of extracellular cGMP restores learning in the Y-maze. The underlying mechanisms remain unknown. It also remains unknown whether extracellular cGMP improves neuroinflammation or restores spatial learning in hyperammonemic rats and if it affects differently reference and working memory. The aims of this work were: Spatial working and reference memory were assessed using the radial and Morris water mazes and neuroinflammation by immunohistochemistry and Western blot. Membrane expression of NMDA and AMPA receptor subunits was analyzed using the BS3 crosslinker. Extracellular cGMP was administered intracerebrally using osmotic minipumps. Chronic hyperammonemia induces neuroinflammation in hippocampus, with astrocytes activation and increased IL-1β, which are associated with increased NMDA receptors membrane expression and impaired working memory. This process is not affected by extracellular cGMP. Hyperammonemia also activates microglia and increases TNF-α, alters membrane expression of AMPA receptor subunits (increased GluA1 and reduced GluA2) and impairs reference memory. All these changes are reversed by extracellular cGMP. These results show that extracellular cGMP modulates spatial reference memory but not working memory. This would be mediated by modulation of TNF-α levels and of membrane expression of GluA1 and GluA2 subunits of AMPA receptors.
Hirota, Jeremy A; Gold, Matthew J; Hiebert, Paul R; Parkinson, Leigh G; Wee, Tracee; Smith, Dirk; Hansbro, Phil M; Carlsten, Chris; VanEeden, Stephan; Sin, Don D; McNagny, Kelly M; Knight, Darryl A
Exposure to particulate matter (PM), a major component of air pollution, contributes to increased morbidity and mortality worldwide. Inhaled PM induces innate immune responses by airway epithelial cells that may lead to the exacerbation or de novo development of airway disease. We have previously shown that 10-μm PM (PM10) activates the nucleotide-binding domain, leucine-rich repeat protein (NLRP) 3 inflammasome in human airway epithelial cells. Our objective was to determine the innate and adaptive immune responses mediated by the airway epithelium NLRP3 inflammasome in response to PM10 exposure. Using in vitro cultures of human airway epithelial cells and in vivo studies with wild-type and Nlrp3(-/-) mice, we investigated the downstream consequences of PM10-induced NLPR3 inflammasome activation on cytokine production, cellular inflammation, dendritic cell activation, and PM10-facilitated allergic sensitization. PM10 activates an NLRP3 inflammasome/IL-1 receptor I (IL-1RI) axis in airway epithelial cells, resulting in IL-1β, CC chemokine ligand-20, and granulocyte/macrophage colony-stimulating factor production, which is associated with dendritic cell activation and lung neutrophilia. Despite these profound innate immune responses in the airway epithelium, the NLRP3 inflammasome/IL-1RI axis is dispensable for PM10-facilitated allergic sensitization. We demonstrate the importance of the lung NLRP3 inflammasome in mediating PM10 exposure-associated innate, but not adaptive, immune responses. Our study highlights a mechanism by which PM10 exposure can contribute to the exacerbation of airway disease, but not PM10-facilitated allergic sensitization.
Roundtree, Harrison M.; Simeone, Timothy A.; Johnson, Chaz; Matthews, Stephanie A.; Samson, Kaeli K.; Simeone, Kristina A.
other epilepsy models. Citation: Roundtree HM, Simeone TA, Johnson C, Matthews SA, Samson KK, Simeone KA. Orexin receptor antagonism improves sleep and reduces seizures in Kcna1-null mice. SLEEP 2016;39(2):357–368. PMID:26446112
Farrar, Andrew M; Pereira, Mariana; Velasco, Francisco; Hockemeyer, Jörg; Müller, Christa E; Salamone, John D
Organisms frequently make effort-related decisions based upon assessments of motivational value and response costs. Energy-related dysfunctions such as psychomotor slowing and apathy are critically involved in some clinical syndromes. Dopamine (DA), particularly in the nucleus accumbens, regulates effort-related processes. Dopamine antagonism and accumbens dopamine depletions cause rats performing on choice tasks to reallocate their behavior away from food-reinforced tasks that have high response requirements. There is evidence of a functional interaction between DA and adenosine A(2A) receptors in the neostriatum and nucleus accumbens. The present experiments were conducted to determine if adenosine A(2A) receptor antagonism could reverse the effects of dopamine receptor antagonism on instrumental behavior and effort-related choice. The adenosine A(2A) receptor antagonist MSX-3 was investigated for its ability to reverse the effects of the dopamine receptor antagonist haloperidol (0.1 mg/kg) on fixed ratio 5 instrumental lever-pressing and on response allocation using a concurrent lever-pressing/chow-feeding choice task. Haloperidol significantly suppressed fixed ratio 5 responding, and with rats responding on the concurrent choice task, it altered choice behavior, significantly reducing lever-pressing for food and increasing chow intake. Injections of MSX-3 (0.5-2.0 mg/kg) produced a dose-related attenuation of the effects of 0.1 mg/kg haloperidol on both tasks. The high dose of MSX-3, when administered in the absence of haloperidol, did not significantly affect responding on either task. Adenosine and dopamine systems interact to regulate instrumental behavior and effort-related processes, which may have implications for the treatment of psychiatric symptoms such as psychomotor slowing or anergia.
Chen, Sisi; Luetje, Charles W.
Many insect behaviors are driven by olfaction, making insect olfactory receptors (ORs) appealing targets for insect control. Insect ORs are odorant-gated ion channels, with each receptor thought to be composed of a representative from a large, variable family of odorant binding subunits and a highly conserved co-receptor subunit (Orco), assembled in an unknown stoichiometry. Synthetic Orco directed agonists and antagonists have recently been identified. Several Orco antagonists have been shown to act via an allosteric mechanism to inhibit OR activation by odorants. The high degree of conservation of Orco across insect species results in Orco antagonists having broad activity at ORs from a variety of insect species and suggests that the binding site for Orco ligands may serve as a modulatory site for compounds endogenous to insects or may be a target of exogenous compounds, such as those produced by plants. To test this idea, we screened a series of biogenic and trace amines, identifying several as Orco antagonists. Of particular interest were tryptamine, a plant-produced amine, and tyramine, an amine endogenous to the insect nervous system. Tryptamine was found to be a potent antagonist of Orco, able to block Orco activation by an Orco agonist and to allosterically inhibit activation of ORs by odorants. Tyramine had effects similar to those of tryptamine, but was less potent. Importantly, both tryptamine and tyramine displayed broad activity, inhibiting odorant activation of ORs of species from three different insect orders (Diptera, Lepidoptera and Coleoptera), as well as odorant activation of six diverse ORs from a single species (the human malaria vector mosquito, Anopheles gambiae). Our results suggest that endogenous and exogenous natural compounds serve as Orco ligands modulating insect olfaction and that Orco can be an important target for the development of novel insect repellants. PMID:25075297
Giancane, Gabriella; Minoia, Francesca; Davì, Sergio; Bracciolini, Giulia; Consolaro, Alessandro; Ravelli, Angelo
Systemic juvenile idiopathic arthritis (sJIA) is the form of childhood arthritis whose treatment is most challenging. The demonstration of the prominent involvement of interleukin (IL)-1 in disease pathogenesis has provided the rationale for the treatment with biologic medications that antagonize this cytokine. The three IL-1 blockers that have been tested so far (anakinra, canakinumab, and rilonacept) have all been proven effective and safe, although only canakinumab is currently approved for use in sJIA. The studies on IL-1 inhibition in sJIA published in the past few years suggest that children with fewer affected joints, higher neutrophil count, younger age at disease onset, shorter disease duration, or, possibly, higher ferritin level may respond better to anti-IL-1 treatment. In addition, it has been postulated that use of IL-1 blockade as first-line therapy may take advantage of a “window of opportunity,” in which disease pathophysiology can be altered to prevent the occurrence of chronic arthritis. In this review, we analyze the published literature on IL-1 inhibitors in sJIA and discuss the rationale underlying the use of these medications, the results of therapeutic studies, and the controversial issues. PMID:27999545
Robinson, J.E.; Fish, E.W.; Krouse, M.C.; Thorsell, A.; Heilig, M.; Malanga, C.J.
Rationale The abuse potential of opioids may be due to their reinforcing and rewarding effects, which may be attenuated by neurokinin-1 receptor (NK1R) antagonists. Objective To measure the effects of opioid and neurokinin-1 (NK1R) receptor blockade on the potentiation of brain stimulation reward (BSR) by morphine using the intracranial self-stimulation (ICSS) method. Methods Adult male C57BL/6J mice (n = 15) were implanted with unipolar stimulating electrodes in the lateral hypothalamus and trained to respond for varying frequencies of rewarding electrical stimulation. The BSR threshold (θ0) and maximum response rate (MAX) were determined before and after intraperitoneal administration of saline, morphine (1.0 - 17.0 mg/kg), or the NK1R antagonists L-733,060 (1.0 - 17.0 mg/kg) and L-703,606 (1.0 - 17.0 mg/kg). In morphine antagonism experiments, naltrexone (0.1 – 1.0 mg/kg) or 10.0 mg/kg L-733,060 or L-703,606 was administered 15 minutes before morphine (1.0 - 10.0 mg/kg) or saline. Results Morphine dose-dependently decreased θ0 (maximum effect = 62% of baseline) and altered MAX when compared to saline. L-703,606 and L-733,060 altered θ0 without affecting MAX. 10.0 mg/kg L-733,060 and L-703,606, which did not affect θ0 or MAX, attenuated the effects of 3.0 and 10.0 mg/kg morphine. 1.0 and 0.3 mg/kg naltrexone blocked the effects of 10.0 mg/kg morphine. Naltrexone given before saline did not affect θ0 or MAX. Conclusions The decrease in θ0 by morphine reflects its rewarding effects, which were attenuated by NK1R and opioid receptor blockade. These results demonstrate the importance of substance P signaling during limbic reward system activation by opioids. PMID:21909635
Collison, Kate S; Inglis, Angela; Shibin, Sherin; Andres, Bernard; Ubungen, Rosario; Thiam, Jennifer; Mata, Princess; Al-Mohanna, Futwan A
We have previously showed that lifetime exposure to aspartame, commencing in utero via the mother's diet, may impair insulin tolerance and cause behavioral deficits in adulthood via mechanisms which are incompletely understood. The role of the CNS in regulating glucose homeostasis has been highlighted by recent delineation of the gut-brain axis, in which N-methyl-d-aspartic acid receptors (NMDARs) are important in maintaining glucose homeostasis, in addition to regulating certain aspects of behavior. Since the gut-brain axis can be modulated by fetal programming, we hypothesized that early-life NMDAR antagonism may affect aspartame-induced glucose deregulation in adulthood, and may alter the aspartame behavioral phenotype. Accordingly, C57Bl/6J mice were chronically exposed to aspartame commencing in utero, in the presence and absence of maternal administration of the competitive NMDAR antagonist CGP 39551, from conception until weaning. Drug/diet interactions in adulthood glucocentric and behavioral parameters were assessed. Aspartame exposure elevated blood glucose and impaired insulin-induced glucose disposal during an insulin tolerance test, which could be normalized by NMDAR antagonism. The same effects were not observed in control diet mice, suggesting an early-life drug/diet interaction. Behavioral analysis of adult offspring indicated that NMDAR antagonism of control diet mice caused hyperlocomotion and impaired spatial navigation. Conversely hypolocomotion, reduced exploratory activity and increased anxiety-related behavior were apparent in aspartame diet mice with early-life NMDAR antagonism. significant drug/diet interactions in glucocentric and behavioral parameters were identified in aspartame-exposed mice with early-life NMDAR antagonism. This suggests a possible involvement of early NMDAR interactions in aspartame-impaired glucose homeostasis and behavioral deficits. Copyright © 2016 Elsevier Inc. All rights reserved.
Vilela, Márcia Carvalho; Lima, Graciela Kunrath; Rodrigues, David Henrique; Lacerda-Queiroz, Norinne; Pedroso, Vinicius Sousa Pietra; de Miranda, Aline Silva; Rachid, Milene Alvarenga; Kroon, Erna Geessien; Campos, Marco Antônio; Teixeira, Mauro Martins; Teixeira, Antonio Lucio
Herpes simplex virus type 1 (HSV-1) is a human pathogen that may cause severe encephalitis. The exacerbated immune response against the virus contributes to the disease severity and death. Platelet activating factor (PAF) is a mediator capable of inducing increase in vascular permeability, production of cytokines on endothelial cells and leukocytes. We aimed to investigate the activation of PAF receptor (PAFR) and its contribution to the severity of the inflammatory response in the brain following HSV-1 infection. C57BL/6 wild-type (WT) and PAFR deficient (PAFR(-/-)) mice were inoculated intracranially with 10(4) plaque-forming units (PFU) of HSV-1. Visualization of leukocyte recruitment was performed using intravital microscopy. Cells infiltration in the brain tissue were analyzed by flow cytometry. Brain was removed for chemokine assessment by ELISA and for histopathological analysis. The pharmacological inhibition by the PAFR antagonist UK-74,505 was also analyzed. In PAFR(-/-) mice, there was delayed lethality but no difference in viral load. Histopathological analysis of infected PAFR(-/-) mice showed that brain lesions were less severe when compared to their WT counterparts. Moreover, PAFR(-/-) mice showed less TCD4(+), TCD8(+) and macrophages in brain tissue. This reduction of the presence of leukocytes in parenchyma may be mechanistically explained by a decrease in leukocytes rolling and adhesion. PAFR(-/-) mice also presented a reduction of the chemokine CXCL9 in the brain. In addition, by antagonizing PAFR, survival of C57BL/6 infected mice increased. Altogether, our data suggest that PAFR plays a role in the pathogenesis of experimental HSV-1 meningoencephalitis, and its blockade prevents severe disease manifestation.
Dandash, Orwa; Harrison, Ben J; Adapa, Ram; Gaillard, Raphael; Giorlando, Francesco; Wood, Stephen J; Fletcher, Paul C; Fornito, Alex
The psychotomimetic effect of the N-methyl-D-aspartate receptor (NMDAR) antagonist ketamine is thought to arise from a functional modulation of the brain's fronto-striato-thalamic (FST) circuits. Animal models suggest a pronounced effect on ventral ‘limbic' FST systems, although recent work in patients with psychosis and high-risk individuals suggests specific alterations of dorsal ‘associative' FST circuits. Here, we used functional magnetic resonance imaging to investigate the effects of a subanesthetic dose of ketamine on measures of functional connectivity as indexed by the temporal coherence of spontaneous neural activity in both dorsal and ventral FST circuits, as well as their symptom correlates. We adopted a placebo-controlled, double-blind, randomized, repeated-measures design in which 19 healthy participants received either an intravenous saline infusion or a racemic mixture of ketamine (100 ng/ml) separated by at least 1 week. Compared with placebo, ketamine increased functional connectivity between the dorsal caudate and both the thalamus and midbrain bilaterally. Ketamine additionally increased functional connectivity of the ventral striatum/nucleus accumbens and ventromedial prefrontal cortex. Both connectivity increases significantly correlated with the psychosis-like and dissociative symptoms under ketamine. Importantly, dorsal caudate connectivity with the ventrolateral thalamus and subthalamic nucleus showed inverse correlation with ketamine-induced symptomatology, pointing to a possible resilience role to disturbances in FST circuits. Although consistent with the role of FST in mediating psychosis, these findings contrast with previous research in clinical samples by suggesting that acute NMDAR antagonism may lead to psychosis-like experiences via a mechanism that is distinct from that implicated in frank psychotic illness. PMID:25141922
M'Kadmi, Céline; Leyris, Jean-Philippe; Onfroy, Lauriane; Galés, Céline; Saulière, Aude; Gagne, Didier; Damian, Marjorie; Mary, Sophie; Maingot, Mathieu; Denoyelle, Séverine; Verdié, Pascal; Fehrentz, Jean-Alain; Martinez, Jean; Banères, Jean-Louis; Marie, Jacky
The G protein-coupled receptor GHS-R1a mediates ghrelin-induced growth hormone secretion, food intake, and reward-seeking behaviors. GHS-R1a signals through Gq, Gi/o, G13, and arrestin. Biasing GHS-R1a signaling with specific ligands may lead to the development of more selective drugs to treat obesity or addiction with minimal side effects. To delineate ligand selectivity at GHS-R1a signaling, we analyzed in detail the efficacy of a panel of synthetic ligands activating the different pathways associated with GHS-R1a in HEK293T cells. Besides β-arrestin2 recruitment and ERK1/2 phosphorylation, we monitored activation of a large panel of G protein subtypes using a bioluminescence resonance energy transfer-based assay with G protein-activation biosensors. We first found that unlike full agonists, Gq partial agonists were unable to trigger β-arrestin2 recruitment and ERK1/2 phosphorylation. Using G protein-activation biosensors, we then demonstrated that ghrelin promoted activation of Gq, Gi1, Gi2, Gi3, Goa, Gob, and G13 but not Gs and G12. Besides, we identified some GHS-R1a ligands that preferentially activated Gq and antagonized ghrelin-mediated Gi/Go activation. Finally, we unambiguously demonstrated that in addition to Gq, GHS-R1a also promoted constitutive activation of G13. Importantly, we identified some ligands that were selective inverse agonists toward Gq but not of G13. This demonstrates that bias at GHS-R1a signaling can occur not only with regard to agonism but also to inverse agonism. Our data, combined with other in vivo studies, may facilitate the design of drugs selectively targeting individual signaling pathways to treat only the therapeutically relevant function. PMID:26363071
Skor, Maxwell N.; Wonder, Erin L.; Kocherginsky, Masha; Goyal, Anju; Hall, Ben A.; Cai, Yi; Conzen, Suzanne D.
Purpose: Triple-negative breast cancer (TNBC) accounts for 10-20% of newly diagnosed invasive breast cancer. Finding effective targets for chemotherapy-resistant TNBC has proven difficult in part because of TNBC’s molecular heterogeneity. We have previously reported that, likely because of GR’s anti-apoptotic activity in ER-negative breast epithelial and cancer cells, high glucocorticoid receptor (GR) expression/activity in early-stage TNBC significantly correlates with chemotherapy-resistance and increased recurrence. We hypothesized that pre-treatment with mifepristone, a (GR)-antagonist, would potentiate the efficacy of chemotherapy in GR+ TNBC by inhibiting GR’s anti-apoptotic signaling pathways and increasing the cytotoxic efficiency of chemotherapy. Experimental Design: TNBC cell apoptosis was examined in the context of physiological glucocorticoid concentrations, chemotherapy, and/or pharmacologic concentrations of mifepristone. We used high-throughput live microscopy with continuous recording to measure apoptotic cells stained with a fluorescent dye, and Western analysis to detect caspase-3 and PARP cleavage. The effect of mifepristone on GR-mediated gene expression was also measured. TNBC xenograft studies were performed in female severe combined immunodeficient (SCID) mice and tumors were measured following treatment with vehicle, paclitaxel or mifepristone/paclitaxel. Results: We found that although mifepristone treatment alone had no significant effect on TNBC cell viability or clonogenicity in the absence of chemotherapy, the addition of mifepristone to dexamethasone/paclitaxel treatment significantly increased cytotoxicity and caspase-3/PARP cleavage. Mifepristone also antagonized GR-induced SGK1 and MKP1/DUSP1 gene expression, while significantly augmenting paclitaxel-induced GR+ MDA-MB-231 xenograft tumor shrinkage in vivo. Conclusions: These results suggest that mifepristone pre-treatment could be a useful strategy for increasing tumor cell
Uller, Lena; Mathiesen, Jesper Mosolff; Alenmyr, Lisa; Korsgren, Magnus; Ulven, Trond; Högberg, Thomas; Andersson, Gunnar; Persson, Carl GA; Kostenis, Evi
Background Mast cell-derived prostaglandin D2 (PGD2), may contribute to eosinophilic inflammation and mucus production in allergic asthma. Chemoattractant receptor homologous molecule expressed on TH2 cells (CRTH2), a high affinity receptor for prostaglandin D2, mediates trafficking of TH2-cells, mast cells, and eosinophils to inflammatory sites, and has recently attracted interest as target for treatment of allergic airway diseases. The present study involving mice explores the specificity of CRTH2 antagonism of TM30089, which is structurally closely related to the dual TP/CRTH2 antagonist ramatroban, and compares the ability of ramatroban and TM30089 to inhibit asthma-like pathology. Methods Affinity for and antagonistic potency of TM30089 on many mouse receptors including thromboxane A2 receptor mTP, CRTH2 receptor, and selected anaphylatoxin and chemokines receptors were determined in recombinant expression systems in vitro. In vivo effects of TM30089 and ramatroban on tissue eosinophilia and mucus cell histopathology were examined in a mouse asthma model. Results TM30089, displayed high selectivity for and antagonistic potency on mouse CRTH2 but lacked affinity to TP and many other receptors including the related anaphylatoxin C3a and C5a receptors, selected chemokine receptors and the cyclooxygenase isoforms 1 and 2 which are all recognized players in allergic diseases. Furthermore, TM30089 and ramatroban, the latter used as a reference herein, similarly inhibited asthma pathology in vivo by reducing peribronchial eosinophilia and mucus cell hyperplasia. Conclusion This is the first report to demonstrate anti-allergic efficacy in vivo of a highly selective small molecule CRTH2 antagonist. Our data suggest that CRTH2 antagonism alone is effective in mouse allergic airway inflammation even to the extent that this mechanism can explain the efficacy of ramatroban. PMID:17328802
Smith, Dirk E.; Lipsky, Brian P.; Russell, Chris; Ketchem, Randal R.; Kirchner, Jacqueline; Hensley, Kelly; Boissonneault, Vincent; Plante, Marie-Michèle; Rivest, Serge; Huang, Yangyang; Friedman, Wilma; Sims, John E.
SUMMARY IL-1 has multiple functions in both the periphery and the central nervous system (CNS) and is regulated at many levels. We identified a novel isoform of the IL-1R Accessory Protein (termed AcPb) that is expressed exclusively in the CNS. AcPb interacted with IL-1 and the IL-1 receptor but was unable to mediate canonical IL-1 responses. AcPb expression, however, modulated neuronal gene expression in response to IL-1 treatment in vitro. Animals lacking AcPb demonstrated an intact peripheral IL-1 response and developed experimental autoimmune encephalomyelitis (EAE) similarly to wild type mice. AcPb-deficient mice were instead more vulnerable to local inflammatory challenge in the CNS and suffered enhanced neuronal degeneration as compared to AcP-deficient or wild type mice. These findings implicate AcPb as an additional component of the highly regulated IL-1 system and suggest it may play a role in modulating CNS responses to IL-1 and the interplay between inflammation and neuronal survival. PMID:19481478
Rosivatz, Erika; Scholze, Martin; Kortenkamp, Andreas
Background: Many pesticides in current use have recently been revealed as in vitro androgen receptor (AR) antagonists, but information about their combined effects is lacking. Objective: We investigated the combined effects and the competitive AR antagonism of pesticide mixtures. Methods: We used the MDA-kb2 assay to test a combination of eight AR antagonists that did not also possess AR agonist properties (“pure” antagonists; 8 mix: fludioxonil, fenhexamid, ortho-phenylphenol, imazalil, tebuconazole, dimethomorph, methiocarb, pirimiphos-methyl), a combination of five AR antagonists that also showed agonist activity (5 mix: cyprodinil, pyrimethanil, vinclozolin, chlorpropham, linuron), and all pesticides combined (13 mix). We used concentration addition (CA) and independent action (IA) to formulate additivity expectations, and Schild plot analyses to investigate competitive AR antagonism. Results: A good agreement between the effects of the mixture of eight “pure” AR antagonists and the responses predicted by CA was observed. Schild plot analysis revealed that the 8 mix acted by competitive AR antagonism. However, the observed responses of the 5 mix and the 13 mix fell within the “prediction window” boundaries defined by the predicted regression curves of CA and IA. Schild plot analysis with these mixtures yielded anomalous responses incompatible with competitive receptor antagonism. Conclusions: A mixture of widely used pesticides can, in a predictable manner, produce combined AR antagonist effects that exceed the responses elicited by the most potent component alone. Inasmuch as large populations are regularly exposed to mixtures of antiandrogenic pesticides, our results underline the need for considering combination effects for these substances in regulatory practice. PMID:23008280
1. The 5-HT2 receptors subdivision into the 5-HT(2A/2B/2C) subtypes along with the advent of the selective antagonists has allowed a more detailed investigation on the role and therapeutic significance of these subtypes in cognitive functions. The present study further analyzed the 5-HT2 receptors role on memory consolidation. 2. The SB-200646 (a selective 5-HT(2B/2C) receptor antagonist) and LY215840 (a nonselective 5-HT(2/7) receptor antagonist) posttraining administration had no effect on an autoshaped memory consolidation. However, both drugs significantly and differentially antagonized the memory impairments induced by 1-(3-chlorophenyl)piperazine (mCPP), 1-naphtyl-piperazine (1-NP), mesulergine, or N-(3-trifluoromethylphenyl) piperazine (TFMPP). 3. In contrast, SB-200646 failed to modify the facilitatory procognitive effect produced by (+/-)-2.5-dimethoxy-4-iodoamphetamine (DOI) or ketanserin, which were sensitive to MDL100907 (a selective 5-HT2A receptor antagonist) and to a LY215840 high dose. 4. Finally, SB-200646 reversed the learning deficit induced by dizocilpine, but not that by scopolamine: while SB-200646 and MDL100907 coadministration reversed memory deficits induced by both drugs. 5. It is suggested that 5-HT(2B/2C) receptors might be involved on memory formation probably mediating a suppressive or constraining action. Whether the drug-induced memory impairments in this study are explained by simple agonism, antagonism, or inverse agonism at 5-HT2 receptors remains unclear at this time. 6. Notably, the 5-HT2 receptor subtypes blockade may provide some benefit to reverse poor memory consolidation conditions associated with decreasedcholinergic, glutamatergic, and/or serotonergic neurotransmission.
Kasztan, Malgorzata; Fox, Brandon M; Speed, Joshua S; De Miguel, Carmen; Gohar, Eman Y; Townes, Tim M; Kutlar, Abdullah; Pollock, Jennifer S; Pollock, David M
Sickle cell disease (SCD)-associated nephropathy is a major source of morbidity and mortality in patients because of the lack of efficacious treatments targeting renal manifestations of the disease. Here, we describe a long-term treatment strategy with the selective endothelin-A receptor (ETA) antagonist, ambrisentan, designed to interfere with the development of nephropathy in a humanized mouse model of SCD. Ambrisentan preserved GFR at the level of nondisease controls and prevented the development of proteinuria, albuminuria, and nephrinuria. Microscopy studies demonstrated prevention of podocyte loss and structural alterations, the absence of vascular congestion, and attenuation of glomerulosclerosis in treated mice. Studies in isolated glomeruli showed that treatment reduced inflammation and oxidative stress. At the level of renal tubules, ambrisentan treatment prevented the increased excretion of urinary tubular injury biomarkers. Additionally, the treatment strategy prevented tubular brush border loss, diminished tubular iron deposition, blocked the development of interstitial fibrosis, and prevented immune cell infiltration. Furthermore, the prevention of albuminuria in treated mice was associated with preservation of cortical megalin expression. In a separate series of identical experiments, combined ETA and ETB receptor antagonism provided only some of the protection observed with ambrisentan, highlighting the importance of exclusively targeting the ETA receptor in SCD. Our results demonstrate that ambrisentan treatment provides robust protection from diverse renal pathologies in SCD mice, and suggest that long-term ETA receptor antagonism may provide a strategy for the prevention of renal complications of SCD.
Bodnar, R J; Glass, M J; Koch, J E
Intake of either hypotonic or hypertonic saline solutions is modulated in part by the endogenous opioid system. Morphine and selective mu and delta opioid agonists increase saline intake, while general opioid antagonists reduce saline intake in rats. The present study evaluated whether intracerebroventricular administration of general (naltrexone) and selective mu (beta-funaltrexamine, 5-20 micrograms), mu, (naloxonazine, 50 micrograms), kappa (nor-binaltorphamine, 5-20 micrograms), delta (naltrindole, 20 micrograms), or delta 1 (DALCE, 40 micrograms) opioid receptor subtype antagonists altered water intake and either hypotonic (0.6%) or hypertonic (1.7%) saline intake in water-deprived (24 h) rats over a 3-h time course in a two-bottle choice test. Whereas peripheral naltrexone (0.5-2.5 mg/kg) significantly reduced water intake and hypertonic saline intake, central naltrexone (1-50 micrograms) significantly reduced water intake and hypotonic saline intake. Water intake was significantly reduced following mu and kappa receptor antagonism, but not following mu 1, delta, or delta 1 receptor antagonism. In contrast, neither hypotonic nor hypertonic saline intake was significantly altered by any selective antagonist. These data are discussed in terms of opioid receptor subtype control over saline intake relative to the animal's hydrational state and the roles of palatability and/or salt appetite.
Brust, Tarsis F; Hayes, Michael P; Roman, David L; Watts, Val J
The dopamine D2 receptor (DRD2) is a G protein-coupled receptor (GPCR) that is generally considered to be a primary target in the treatment of schizophrenia. First generation antipsychotic drugs (e.g. haloperidol) are antagonists of the DRD2, while second generation antipsychotic drugs (e.g. olanzapine) antagonize DRD2 and 5HT2A receptors. Notably, both these classes of drugs may cause side effects associated with D2 receptor antagonism (e.g. hyperprolactemia and extrapyramidal symptoms). The novel, "third generation" antipsychotic drug, aripiprazole is also used to treat schizophrenia, with the remarkable advantage that its tendency to cause extrapyramidal symptoms is minimal. Aripiprazole is considered a partial agonist of the DRD2, but it also has partial agonist/antagonist activity for other GPCRs. Further, aripiprazole has been reported to have a unique activity profile in functional assays with the DRD2. In the present study the molecular pharmacology of aripiprazole was further examined in HEK cell models stably expressing the DRD2 and specific isoforms of adenylyl cyclase to assess functional responses of Gα and Gβγ subunits. Additional studies examined the activity of aripiprazole in DRD2-mediated heterologous sensitization of adenylyl cyclase and cell-based dynamic mass redistribution (DMR). Aripiprazole displayed a unique functional profile for modulation of G proteins, being a partial agonist for Gαi/o and a robust antagonist for Gβγ signaling. Additionally, aripiprazole was a weak partial agonist for both heterologous sensitization and dynamic mass redistribution.
Machado, Ivana; González, Patricia; Schiöth, Helgi Birgir; Lasaga, Mercedes; Scimonelli, Teresa Nieves
Interleukin-1 beta (IL-1β) significantly influences cognitive processes. Treatments which raise the level of IL-1β in the brain impair memory consolidation in contextual fear conditioning. However, the effect of IL-1β on memory reconsolidation has not yet been established. The melanocortin α-melanocyte-stimulating hormone (α-MSH) exerts potent anti-inflammatory actions by antagonizing the effect of proinflammatory cytokines. Five subtypes of melanocortin receptors (MC1R-MC5R) have been identified, of which MC3R and MC4R are predominant in the central nervous system. The present experiments show that the injection of IL-1β (5 ng/0.25 μl) in dorsal hippocampus up to 30 min after re-exposition to the context decreases freezing during the contextual fear test. Impairment of memory reconsolidation was reversed by treatment with α-MSH (0.05 μg/0.25 μl). Administration of the MC4 receptor antagonist HS014 (0.5 μg/0.25 μl) blocked the effect of α-MSH. These results suggest that IL-1β may influence memory reconsolidation and that activation of central MC4R could lead to improve cognitive performance.
Gao, Qiangguo; Zhang, Yi; Han, Chaofeng; Hu, Xiang; Zhang, Hua; Xu, Xiongfei; Tian, Jun; Liu, Yiqi; Ding, Yuanyuan; Liu, Juan; Wang, Chunmei; Guo, Zhenhong; Yang, Yongguang; Cao, Xuetao
The migration of Th17 cells into central nervous system (CNS) tissue is the key pathogenic step in experimental autoimmune encephalomyelitis (EAE) model. However, the mechanism underlying the pathogenic Th17 cell migration remains elusive. Here we report that blockade of CD47 with CD47-Fc fusion protein is effective in preventing and curing EAE by impairing infiltration of Th17 cells into CNS. However, CD47 deficiency does not directly impair the migration of Th17 cells. Mechanistic studies showed that CD47 deficiency inhibited degradation of inducible nitric oxide synthase (iNOS) in proteasome of macrophages by Src activation and led to the increased nitric oxide (NO) production. Then NO suppressed inflammasome activation-induced IL-1β production. This lower IL-1β reduces the expression of IL-1R1 and migration-related chemokine receptors on CD47(-/-) Th17 cells, inhibiting the ability of Th17 cells to infiltrate into the CNS of CD47(-/-) mice and therefore suppressing EAE development. In vivo administration of exogenous IL-1β indeed promoted the infiltration CD47(-/-) Th17 cells into CNS and antagonized the protective role of CD47 deficiency in EAE pathogenesis. Our results demonstrate a potential preventive and therapeutic application of CD47 blockade in controlling EAE development.
Giai, Constanza; Gonzalez, Cintia D; Sabbione, Florencia; Garofalo, Ailin; Ojeda, Diego; Sordelli, Daniel O; Trevani, Analía S; Gómez, Marisa I
Interleukin 1 (IL-1) β is a critical cytokine that orchestrates host defenses against Staphylococcus aureus and is crucial for the eradication of bacteria. The production and action of IL-1β are regulated by multiple control pathways. Among them, IL-1RII (the type II IL-1 receptor) acts as a decoy receptor and has been shown to regulate the biological effects of IL-1β. High levels of soluble IL-1RII are present in septic patients; however, the stimuli that regulate the expression and release of IL-1RII in pathological conditions are incompletely elucidated. In the present study, we demonstrated the ability of S. aureus and protein A to induce IL-1RII shedding in myeloid cells. The positive modulation of IL-1RII expression and cleavage was associated with the failure to detect IL-1β in response to S. aureus both in vitro and in vivo, suggesting that the soluble form of the receptor could be masking the availability of IL-1β. The absence of detectable IL-1β was associated with low levels of inflammatory cytokines and chemokines known to be regulated by IL-1β and with increased bacterial persistence. Modulation of decoy receptors during systemic S. aureus infection is proposed as a new strategy used by this bacterium to evade the immune response.
Virsolvy, Anne; Farah, Charlotte; Pertuit, Nolwenn; Kong, Lingyan; Lacampagne, Alain; Reboul, Cyril; Aimond, Franck; Richard, Sylvain
Ranolazine is a recently developed drug used for the treatment of patients with chronic stable angina. It is a selective inhibitor of the persistent cardiac Na+ current (INa), and is known to reduce the Na+-dependent Ca2+ overload that occurs in cardiomyocytes during ischemia. Vascular effects of ranolazine, such as vasorelaxation,have been reported and may involve multiple pathways. As voltage-gated Na+ channels (Nav) present in arteries play a role in contraction, we hypothesized that ranolazine could target these channels. We studied the effects of ranolazine in vitro on cultured aortic smooth muscle cells (SMC) and ex vivo on rat aortas in conditions known to specifically activate or promote INa. We observed that in the presence of the Nav channel agonist veratridine, ranolazine inhibited INa and intracellular Ca2+ calcium increase in SMC, and arterial vasoconstriction. In arterial SMC, ranolazine inhibited the activity of tetrodotoxin-sensitive voltage-gated Nav channels and thus antagonized contraction promoted by low KCl depolarization. Furthermore, the vasorelaxant effects of ranolazine, also observed in human arteries and independent of the endothelium, involved antagonization of the α1-adrenergic receptor. Combined α1-adrenergic antagonization and inhibition of SMCs Nav channels could be involved in the vascular effects of ranolazine. PMID:26655634
Virsolvy, Anne; Farah, Charlotte; Pertuit, Nolwenn; Kong, Lingyan; Lacampagne, Alain; Reboul, Cyril; Aimond, Franck; Richard, Sylvain
Ranolazine is a recently developed drug used for the treatment of patients with chronic stable angina. It is a selective inhibitor of the persistent cardiac Na(+) current (INa), and is known to reduce the Na(+)-dependent Ca(2+) overload that occurs in cardiomyocytes during ischemia. Vascular effects of ranolazine, such as vasorelaxation,have been reported and may involve multiple pathways. As voltage-gated Na(+) channels (Nav) present in arteries play a role in contraction, we hypothesized that ranolazine could target these channels. We studied the effects of ranolazine in vitro on cultured aortic smooth muscle cells (SMC) and ex vivo on rat aortas in conditions known to specifically activate or promote INa. We observed that in the presence of the Nav channel agonist veratridine, ranolazine inhibited INa and intracellular Ca(2+) calcium increase in SMC, and arterial vasoconstriction. In arterial SMC, ranolazine inhibited the activity of tetrodotoxin-sensitive voltage-gated Nav channels and thus antagonized contraction promoted by low KCl depolarization. Furthermore, the vasorelaxant effects of ranolazine, also observed in human arteries and independent of the endothelium, involved antagonization of the α1-adrenergic receptor. Combined α1-adrenergic antagonization and inhibition of SMCs Nav channels could be involved in the vascular effects of ranolazine.
Farb, Thomas B; Adeva, Marta; Beauchamp, Thomas J; Cabrera, Over; Coates, David A; DeShea Meredith, Tamika; Droz, Brian A; Efanov, Alexander; Ficorilli, James V; Gackenheimer, Susan L; Martinez-Grau, Maria A; Molero, Victoriano; Ruano, Gema; Statnick, Michael A; Suter, Todd M; Syed, Samreen K; Toledo, Miguel A; Willard, Francis S; Zhou, Xin; Bokvist, Krister B; Barrett, David G
Incretin and insulin responses to nutrient loads are suppressed in persons with diabetes, resulting in decreased glycemic control. Whereas agents including sulfonylureas and Dipeptidyl peptidase-4 inhibitors (DPP4i) partially reverse these effects and provide therapeutic benefit, their modes of action limit efficacy. Because somatostatin (SST) has been shown to suppress both insulin and GLP-1 secretion through the Gi-coupled SST receptor 5 (SSTR5) isoform in vitro, antagonism of SSTR5 may improve glycemic control via intervention in both pathways. Here we show that a novel potent and selective SSTR5 antagonist reverses the blunting effects of SST on insulin secretion from isolated human islets, and demonstrate for the first time that SSTR5 antagonism affords increased levels of systemic GLP-1 in vivo. Knocking out Sstr5 in mice provided a similar increase in systemic GLP-1 levels, which were not increased further by treatment with the antagonist. Treatment of mice with the SSTR5 antagonist in combination with a DPP4i afforded increases in systemic GLP-1 levels that were more than additive, and resulted in greater glycemic control compared to either agent alone. In isolated human islets, the SSTR5 antagonist completely reversed the inhibitory effect of exogenous SST-14 on insulin secretion. Taken together, these data suggest that SSTR5 antagonism should increase circulating GLP-1 levels and stimulate insulin secretion (directly and via GLP-1) in humans, improving glycemic control in patients with diabetes. Copyright © 2017 Endocrine Society.
Gao, Zhan-Guo; Mamedova, Liaman; Tchilibon, Susanna; Gross, Ariel S.; Jacobson, Kenneth A.
The effect of 2,2′-pyridylisatogen tosylate (PIT) on the human P2Y1 receptor and on other recombinant P2Y receptors has been studied. We first examined the modulation by PIT of the agonist-induced accumulation of inositol phosphates. PIT blocked 2-methylthio-ADP (2-MeSADP)-induced accumulation of inositol phosphates in 1321N1 astrocytoma cells stably expressing human P2Y1 receptors in a non-competitive and concentration-dependent manner. The IC50 for reduction of the maximal agonist effect was 0.14 μM. In contrast, MRS2179, a competitive P2Y1 receptor antagonist, parallel-shifted the agonist concentration–response curve to the right. PIT also concentration-dependently blocked the P2Y1 receptor signaling induced by the endogenous agonists, ADP and ATP. A simple structural analogue of PIT was synthesized and found to be inactive as a P2Y1 receptor antagonist, suggesting that the nitroxyl group of PIT is a necessary structural component for P2Y1 receptor antagonism. We next examined the possible modulation of the binding of the newly available antagonist radioligand for the P2Y1 receptor, [3H] MRS2279. It was found that PIT (0.01–10 μM) did not inhibit [3H] MRS2279 binding to the human P2Y1 receptor. PIT (10 μM) had no effect on the competition for [3H] MRS2279 binding by agonists, ADP and ATP, suggesting that its antagonism of the P2Y1 receptor may be allosteric. PIT had no significant effect on agonist activation of other P2Y receptors, including P2Y2, P2Y4, P2Y6, P2Y11 and P2Y12 receptors. Thus, PIT selectively and non-competitively blocked P2Y1 receptor signaling without affecting nucleotide binding. PMID:15193995
Flores, África; Herry, Cyril; Maldonado, Rafael; Berrendero, Fernando
Orexins are hypothalamic neuropeptides recently involved in the regulation of emotional memory. The basolateral amygdala, an area orchestrating fear memory processes, appears to be modulated by orexin transmission during fear extinction. However, the neuronal types within the basolateral amygdala involved in this modulation remain to be elucidated. We used retrograde tracing combined with immunofluorescence techniques in mice to identify basolateral amygdala projection neurons and cell subpopulations in this brain region influenced by orexin transmission during contextual fear extinction consolidation. Treatment with the orexin-1 receptor antagonist SB334867 increased the activity of basolateral amygdala neurons projecting to infralimbic medial prefrontal cortex during fear extinction. GABAergic interneurons expressing calbindin, but not parvalbumin, were also activated by orexin-1 receptor antagonism in the basolateral amygdala. These data identify neuronal circuits and cell populations of the amygdala associated with the facilitation of fear extinction consolidation induced by the orexin-1 receptor antagonist SB334867.
Warot, D; Danjou, P; Douillet, P; Keane, P; Puech, A J
Pharmacological studies revealed that SR 25776 possesses marked stimulant activity characteristic of a partial inverse agonist of benzodiazepine receptor. The effects of SR 25776 500 mg alone and in combination with triazolam 0.25 mg on psychomotor performance and memory were assessed in 8 healthy consenting male volunteers in a double-blind placebo controlled trial. Treatment effects were monitored before and two and half hours following oral medication. The present study suggest that at the studied dose SR 25776 may incompletely antagonize the sedative and amnesic effects of a benzodiazepine agonist without producing marked effects of its own.
Yamagata, Atsushi; Yoshida, Tomoyuki; Sato, Yusuke; Goto-Ito, Sakurako; Uemura, Takeshi; Maeda, Asami; Shiroshima, Tomoko; Iwasawa-Okamoto, Shiho; Mori, Hisashi; Mishina, Masayoshi; Fukai, Shuya
Synapse formation is triggered through trans-synaptic interaction between pairs of pre- and postsynaptic adhesion molecules, the specificity of which depends on splice inserts known as ‘splice-insert signaling codes'. Receptor protein tyrosine phosphatase δ (PTPδ) can bidirectionally induce pre- and postsynaptic differentiation of neurons by trans-synaptically binding to interleukin-1 receptor accessory protein (IL-1RAcP) and IL-1RAcP-like-1 (IL1RAPL1) in a splicing-dependent manner. Here, we report crystal structures of PTPδ in complex with IL1RAPL1 and IL-1RAcP. The first immunoglobulin-like (Ig) domain of IL1RAPL1 directly recognizes the first splice insert, which is critical for binding to IL1RAPL1. The second splice insert functions as an adjustable linker that positions the Ig2 and Ig3 domains of PTPδ for simultaneously interacting with the Ig1 domain of IL1RAPL1 or IL-1RAcP. We further identified the IL1RAPL1-specific interaction, which appears coupled to the first-splice-insert-mediated interaction. Our results thus reveal the decoding mechanism of splice-insert signaling codes for synaptic differentiation induced by trans-synaptic adhesion between PTPδ and IL1RAPL1/IL-1RAcP. PMID:25908590
Yamagata, Atsushi; Yoshida, Tomoyuki; Sato, Yusuke; Goto-Ito, Sakurako; Uemura, Takeshi; Maeda, Asami; Shiroshima, Tomoko; Iwasawa-Okamoto, Shiho; Mori, Hisashi; Mishina, Masayoshi; Fukai, Shuya
Synapse formation is triggered through trans-synaptic interaction between pairs of pre- and postsynaptic adhesion molecules, the specificity of which depends on splice inserts known as 'splice-insert signaling codes'. Receptor protein tyrosine phosphatase δ (PTPδ) can bidirectionally induce pre- and postsynaptic differentiation of neurons by trans-synaptically binding to interleukin-1 receptor accessory protein (IL-1RAcP) and IL-1RAcP-like-1 (IL1RAPL1) in a splicing-dependent manner. Here, we report crystal structures of PTPδ in complex with IL1RAPL1 and IL-1RAcP. The first immunoglobulin-like (Ig) domain of IL1RAPL1 directly recognizes the first splice insert, which is critical for binding to IL1RAPL1. The second splice insert functions as an adjustable linker that positions the Ig2 and Ig3 domains of PTPδ for simultaneously interacting with the Ig1 domain of IL1RAPL1 or IL-1RAcP. We further identified the IL1RAPL1-specific interaction, which appears coupled to the first-splice-insert-mediated interaction. Our results thus reveal the decoding mechanism of splice-insert signaling codes for synaptic differentiation induced by trans-synaptic adhesion between PTPδ and IL1RAPL1/IL-1RAcP.
Yamagata, Atsushi; Yoshida, Tomoyuki; Sato, Yusuke; Goto-Ito, Sakurako; Uemura, Takeshi; Maeda, Asami; Shiroshima, Tomoko; Iwasawa-Okamoto, Shiho; Mori, Hisashi; Mishina, Masayoshi; Fukai, Shuya
Synapse formation is triggered through trans-synaptic interaction between pairs of pre- and postsynaptic adhesion molecules, the specificity of which depends on splice inserts known as `splice-insert signaling codes'. Receptor protein tyrosine phosphatase δ (PTPδ) can bidirectionally induce pre- and postsynaptic differentiation of neurons by trans-synaptically binding to interleukin-1 receptor accessory protein (IL-1RAcP) and IL-1RAcP-like-1 (IL1RAPL1) in a splicing-dependent manner. Here, we report crystal structures of PTPδ in complex with IL1RAPL1 and IL-1RAcP. The first immunoglobulin-like (Ig) domain of IL1RAPL1 directly recognizes the first splice insert, which is critical for binding to IL1RAPL1. The second splice insert functions as an adjustable linker that positions the Ig2 and Ig3 domains of PTPδ for simultaneously interacting with the Ig1 domain of IL1RAPL1 or IL-1RAcP. We further identified the IL1RAPL1-specific interaction, which appears coupled to the first-splice-insert-mediated interaction. Our results thus reveal the decoding mechanism of splice-insert signaling codes for synaptic differentiation induced by trans-synaptic adhesion between PTPδ and IL1RAPL1/IL-1RAcP.
Murray, Carol L.; Obiang, Pauline; Bannerman, David; Cunningham, Colm
Interleukin-1 (IL-1) is a key pro-inflammatory cytokine, produced predominantly by peripheral immune cells but also by glia and some neuronal populations within the brain. Its signalling is mediated via the binding of IL-1α or IL-1β to the interleukin-1 type one receptor (IL-1RI). IL-1 plays a key role in inflammation-induced sickness behaviour, resulting in depressed locomotor activity, decreased exploration, reduced food and water intake and acute cognitive deficits. Conversely, IL-1 has also been suggested to facilitate hippocampal-dependent learning and memory: IL-1RI−/− mice have been reported to show deficits on tasks of visuospatial learning and memory. We sought to investigate whether there is a generalised hippocampal deficit in IL-1RI−/− animals. Therefore, in the current study we compared wildtype (WT) mice to IL-1RI−/− mice using a variety of hippocampal-dependent learning and memory tasks, as well as tests of anxiety and locomotor activity. We found no difference in performance of the IL-1RI−/− mice compared to WT mice in a T-maze working memory task. In addition, the IL-1RI−/− mice showed normal learning in various spatial reference memory tasks including the Y-maze and Morris mater maze, although there was a subtle deficit in choice behaviour in a spatial discrimination, beacon watermaze task. IL-1RI−/− mice also showed normal memory for visuospatial context in the contextual fear conditioning paradigm. In the open field, IL-1RI−/− mice showed a significant increase in distance travelled and rearing behaviour compared to the WT mice and in the elevated plus-maze spent more time in the open arms than did the WT animals. The data suggest that, contrary to prior studies, IL-1RI−/− mice are not robustly impaired on hippocampal-dependent memory and learning but do display open field hyperactivity and decreased anxiety compared to WT mice. The results argue for a careful evaluation of the roles of endogenous IL-1 in
Background Accumulating evidence supports the role of the mineralocorticoid receptor (MR) in the pathogenesis of diabetic nephropathy. These findings have generated renewed interest in novel MR antagonists with improved selectivity against other nuclear hormone receptors and a potentially reduced risk of hyperkalemia. Characterization of novel MR antagonists warrants establishing translatable biomarkers of activity at the MR receptor. We assessed the translatability of urinary sodium to potassium ratio (Na+/K+) and plasma aldosterone as biomarkers of MR antagonism using eplerenone (Inspra®), a commercially available MR antagonist. Further we utilized these biomarkers to demonstrate antagonism of MR by PF-03882845, a novel compound. Methods The effect of eplerenone and PF-03882845 on urinary Na+/K+ and plasma aldosterone were characterized in Sprague-Dawley rats and spontaneously hypertensive rats (SHR). Additionally, the effect of eplerenone on these biomarkers was determined in healthy volunteers. Drug exposure-response data were modeled to evaluate the translatability of these biomarkers from rats to humans. Results In Sprague-Dawley rats, eplerenone elicited a rapid effect on urinary Na+/K+ yielding an EC50 that was within 5-fold of the functional in vitro IC50. More importantly, the effect of eplerenone on urinary Na+/K+ in healthy volunteers yielded an EC50 that was within 2-fold of the EC50 generated in Sprague-Dawley rats. Similarly, the potency of PF-03882845 in elevating urinary Na+/K+ in Sprague-Dawley rats was within 3-fold of its in vitro functional potency. The effect of MR antagonism on urinary Na+/K+ was not sustained chronically; thus we studied the effect of the compounds on plasma aldosterone following chronic dosing in SHR. Modeling of drug exposure-response data for both eplerenone and PF-03882845 yielded EC50 values that were within 2-fold of that estimated from modeling of drug exposure with changes in urinary sodium and potassium excretion
Nicholson, A. N.; Pascoe, P. A.; Turner, C.; Ganellin, C. R.; Greengrass, P. M.; Casy, A. F.; Mercer, A. D.
1. The effects of 10 mg (+)- and (-)-chlorpheniramine and 5 mg (+)- and (-)-dimethindene on daytime sleep latencies, digit symbol substitution and subjective assessments of mood and well-being were studied in 6 healthy young adult humans. Each subject also took 5 mg triprolidine hydrochloride as an active control and two placebos. 2. Daytime sleep latencies were reduced with triprolidine, (+)-chlorpheniramine and (-)-dimethindene, and subjects also reported that they felt more sleepy after (+)-chlorpheniramine and (-)-dimethindene. Performance on digit symbol substitution was impaired with (+)-chlorpheniramine. 3. Changes in measures with (-)-chlorpheniramine and (+)-dimethindene were not different from changes with placebo. 4. In the present study, changes in measures of drowsiness and performance were limited to the enantiomers with high affinity for the histamine H1-receptor. These findings strongly suggest that sedation can arise from H1-receptor antagonism alone, and provide further support for the belief that the histaminergic system is concerned with the regulation of alertness in man. PMID:1686208
Brust, Tarsis F.; Hayes, Michael P.; Roman, David L.; Watts, Val J.
The dopamine D2 receptor (DRD2) is a G protein-coupled receptor (GPCR) that is generally considered to be a primary target in the treatment of schizophrenia. First generation antipsychotic drugs (e.g. haloperidol) are antagonists of the DRD2, while second generation antipsychotic drugs (e.g. olanzapine) antagonize DRD2 and 5HT2A receptors. Notably, both these classes of drugs may cause side effects associated with D2 receptor antagonism (e.g. hyperprolactemia and extrapyramidal symptoms). The novel, “third generation” antipsychotic drug, aripiprazole is also used to treat schizophrenia, with the remarkable advantage that its tendency to cause extrapyramidal symptoms is minimal. Aripiprazole is considered a partial agonist of the DRD2, but it also has partial agonist/antagonist activity for other GPCRs. Further, aripiprazole has been reported to have a unique activity profile in functional assays with the DRD2. In the present study the molecular pharmacology of aripiprazole was further examined in HEK cell models stably expressing the DRD2 and specific isoforms of adenylyl cyclase to assess functional responses of Gα and Gβγ subunits. Additional studies examined the activity of aripiprazole in DRD2-mediated heterologous sensitization of adenylyl cyclase and cell-based dynamic mass redistribution (DMR). Aripiprazole displayed a unique functional profile for modulation of G proteins, being a partial agonist for Gαi/o and a robust antagonist for Gβγ signaling. Additionally, aripiprazole was a weak partial agonist for both heterologous sensitization and dynamic mass redistribution. PMID:25449598
Li, Ai-Jun; Wang, Qing; Dinh, Thu T; Simasko, Steve M; Ritter, Sue
Mercaptoacetate (MA) is an orexigenic agent reported to block fatty acid (FA) oxidation. Recently, however, we reported evidence from isolated nodose ganglion neurons that MA antagonizes the G protein-coupled long- and medium-chain FA receptor GPR40. GPR40 mediates FA-induced secretion of the satietogenic incretin peptide glucagon-like peptide 1 (GLP-1), by enteroendocrine L cells, as well as FA-induced enhancement of glucose-stimulated insulin secretion. Our results in cultured nodose neurons suggest that MA would also block GPR40 in enteroendocrine cells controlling GLP-1 secretion. If so, this would suggest an alternative mechanism by which MA increases food intake. We tested the hypothesis that MA blocks FA-induced GLP-1 secretion in vitro using cultured STC-1 cells (a murine enteroendocrine cell line) and in vivo in adult male rats. In vitro, MA blocked the increase in both cytosolic Ca(2+)and GLP-1 release stimulated by FAs and also reduced (but less effectively) the response of STC-1 cells to grifolic acid, a partial agonist of the GPR120 FA receptor. In vivo, MA reduced GLP-1 secretion following olive oil gavage while also increasing glucose and decreasing insulin levels. The carnitine palmatoyltransferase 1 antagonist etomoxir did not alter these responses. Results indicate that MA's actions, including its orexigenic effect, are mediated by GPR40 (and possibly GPR120) receptor antagonism and not by blockade of fat oxidation, as previously believed. Analysis of MA's interaction with GPR40 may facilitate understanding of the multiple functions of this receptor and the manner in which FAs participate in the control of hunger and satiety.
Boraschi, Diana; Lucchesi, Davide; Hainzl, Stefan; Leitner, Maria; Maier, Elisabeth; Mangelberger, Doris; Oostingh, Gertie J; Pfaller, Tobias; Pixner, Claudia; Posselt, Gernot; Italiani, Paola; Nold, Marcel F; Nold-Petry, Claudia A; Bufler, Philip; Dinarello, Charles A
The IL-1 family of cytokines encompasses eleven proteins that each share a similar β-barrel structure and bind to Ig-like receptors. Some of the IL-1-like cytokines have been well characterised, and play key roles in the development and regulation of inflammation. Indeed, IL-1α (IL-1F1), IL-1β (IL-1F2), and IL-18 (IL-1F4) are well-known inflammatory cytokines active in the initiation of the inflammatory reaction and in driving Th1 and Th17 inflammatory responses. In contrast, IL-1 receptor antagonist (IL-1Ra, IL-1F3) and the receptor antagonist binding to IL-1Rrp2 (IL-36Ra, IL-1F5) reduce inflammation by blocking the binding of the agonist receptor ligands. In the case of IL-37 (IL-1F7), of which five different splice variants have been described, less is known of its function, and identification of the components of a heterodimeric receptor complex remains unclear. Some studies suggest that IL-37 binds to the α chain of the IL-18 receptor in a non-competitive fashion, and this may explain some of the disparate biological effects that have been reported for mice deficient in the IL-18R. The biological properties of IL-37 are mainly those of down-regulating inflammation, as assessed in models where human IL-37 is expressed in mice. In this review, an overview of the role of IL-37 in the regulation of inflammation is presented. The finding that IL-37 also locates to the nucleus, as do IL-1α and IL-33, for receptor-independent organ/tissue-specific regulation of inflammation is also reviewed.
Poznanski, Piotr; Lesniak, Anna; Korostynski, Michal; Szklarczyk, Klaudia; Lazarczyk, Marzena; Religa, Piotr; Bujalska-Zadrozny, Magdalena; Sadowski, Bogdan; Sacharczuk, Mariusz
The opioid system modulates the central reinforcing effects of ethanol and participates in the etiology of addiction. However, the pharmacotherapy of ethanol dependence targeted on the opioid system is little effective and varies due to individual patients' sensitivity. In the present study, we used two mouse lines with high (HA) and low (LA) activity of the endogenous opioid system to analyze the effect of opioid receptor blockade on ethanol drinking behavior. We found that LA and HA lines characterized by divergent magnitudes of swim stress-induced analgesia also differ in ethanol intake and preference. Downregulation of the opioid system in LA mice was associated with increased ethanol consumption. Treatment with a non-selective opioid receptor antagonist (naloxone) had no effect on ethanol intake in this line. Surprisingly, in HA mice, the blockage of opioid receptors led to excessive ethanol consumption. Moreover, naloxone selectively induced high levels of anxiety- and depressive-like behaviors in HA mice which was attenuated by ethanol. With the use of specific opioid receptor antagonists we showed that the naloxone-induced increase in ethanol drinking in HA mice is mediated mainly by δ and to a lower extent by μ opioid receptors. The effect of δ-opioid receptor antagonism was abolished in HA mice carrying a C320T transition in the δ-opioid receptor gene (EU446125.1), which impairs this receptor's function. Our results indicate that high activity of the opioid system plays a protective role against ethanol dependence. Therefore, its blockage with opioid receptor antagonists may lead to a profound increase in ethanol consumption. Copyright © 2017 Elsevier Ltd. All rights reserved.
Ibrahim, José-Noel; Chouery, Eliane; Lecron, Jean-Claude; Mégarbané, André; Medlej-Hashim, Myrna
Familial Mediterranean fever (FMF) is a recessive autoinflammatory disorder. The balance between the pro-inflammatory cytokine IL-1β and its receptor antagonist IL-1RA plays an important role in the development of FMF. In order to determine a possible association of polymorphisms in IL-1β and IL-1RA genes with occurrence and/or severity of the disease, 42 genetically confirmed FMF patients and 42 controls were genotyped for IL-1β(-511C/T), IL-1β(-31T/C), IL1-1β(+3954T/C) and IL-1RA VNTR polymorphisms. IL-1β and IL-1RA levels were evaluated by multiplex ELISA in supernatants of PBMC cultures of 30 FMF patients with and without 24h stimulation of monocytes by LPS. The CC genotype and C allele at positions -31 and + 3954 of IL-1β gene were more frequent in FMF patients than in controls. FMF patients carriers of IL-1β(-31) CC genotype were associated with a 2-fold increase in LPS-induced IL-1β secretion as well as a higher disease severity score (11.2 ± 2.9) when compared to patients carrying the TC and TT genotypes (6.1 ± 2.1 and 4.5 ± 2.4, respectively). These results indicate that IL-1β gene polymorphisms at positions -31 and + 3954 may be associated with an increased risk for FMF. IL-1β(-31) contributes also to the severity of the disease, probably by modulating IL-1β synthesis. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
van Asseldonk, Edwin J P; van Poppel, Pleun C M; Ballak, Dov B; Stienstra, Rinke; Netea, Mihai G; Tack, Cees J
Inflammation associated with obesity is involved in the development of insulin resistance. We hypothesized that anti-inflammatory treatment with the Interleukin-1 receptor antagonist anakinra would improve insulin sensitivity. In an open label proof-of-concept study, we included overweight patients diagnosed with type 1 diabetes with an HbA1c level over 7.5%. Selecting insulin resistant patients with longstanding type 1 diabetes allowed us to study the effects of anakinra on insulin sensitivity. Patients were treated with 100mg anakinra daily for one week. Insulin sensitivity, insulin need and blood glucose profiles were measured before, after one week and after four weeks of follow-up. Fourteen patients completed the study. One week of anakinra treatment led to an improvement of insulin sensitivity, an effect that was sustained for four weeks. Similarly, glucose profiles, HbA1c levels and insulin needs improved. In conclusion, one week of treatment with anakinra improves insulin sensitivity in patients with type 1 diabetes.
Gao, Peng; Gibson, Peter G; Baines, Katherine J; Yang, Ian A; Upham, John W; Reynolds, Paul N; Hodge, Sandra; James, Alan L; Jenkins, Christine; Peters, Matthew J; Zhang, Jie; Simpson, Jodie L
Galectin-3 (gal-3), a member of the β-galactoside-binding animal lectins, is involved in the recruitment, activation and removal of neutrophils. Neutrophilic asthma is characterized by a persistent elevation of airway neutrophils and impaired efferocytosis. We hypothesized that sputum gal-3 would be reduced in neutrophilic asthma and the expression of gal-3 would be associated with other markers of neutrophilic inflammation. Adults with asthma (n = 80) underwent a sputum induction following clinical assessment and blood collection. Sputum was dispersed for a differential cell count and ELISA assessment of gal-3, gal-3 binding protein (BP), interleukin (IL)-1β, IL-1 receptor antagonist (RA), IL-8 and IL-6. Gal-3 and gal-3BP immunoreactivity were assessed in mixed sputum cells. Sputum gal-3 (median, (q1,q3)) was significantly reduced in neutrophilic asthma (183 ng/mL (91,287)) compared with eosinophilic (293 ng/mL (188,471), p = 0.021) and paucigranulocytic asthma (399 ng/mL (213,514), p = 0.004). The gal-3/gal-3BP ratio and IL-1RA/IL-1β ratio were significantly reduced, while gal-3BP and IL-1β were significantly elevated in neutrophilic asthma compared with eosinophilic and paucigranulocytic asthma. Patients with neutrophilic asthma have impairment in anti-inflammatory ratio of gal-3/gal-3BP and IL-1RA/IL-1β which provides a further framework for exploration into pathologic mechanisms of asthma phenotypes.
Loh, Ryan; Chau, Lily; Aijaz, Ali; Wu, Kevin; Galvez, Roberto
Previous work from our laboratory has shown that nonspecific kappa opioid receptor (KOR) antagonism in primary somatosensory cortex (S1) can inhibit acquisition for the forebrain-dependent associative task, Whisker-Trace Eyeblink conditioning (WTEB). Although studies have demonstrated that KOR activation can alter stimuli salience, our studies controlled for these factors, demonstrating that KOR also plays a role in facilitating learning. KOR has two distinct phases of activation followed by internalization/downregulation, that each independently activate kinases and transcription factors known to mediate task acquisition and memory consolidation respectively. The current study demonstrated that antagonism of the initial phase of KOR activation in S1 via local injections of the g-protein inhibitor, pertussis toxin (PTX), blocked initial WTEB acquisition without affecting retention of the association. In contrast, KOR late phase antagonism in S1 via local injections of the GRK3-specific antagonist, guanidinonaltrindole (GNTI), blocked retention of the WTEB association without affecting task acquisition. Consistent with the known mechanism for KOR activation, KOR protein expression in S1 was found to be decreased following WTEB training, further supporting the involvement of neocortical KOR activation with learning. Prior studies have shown that task acquisition and memory consolidation are mediated by distinct molecular processes; however, little is known regarding a potential mechanism driving these processes. The current study suggests that neocortical KOR activation mediates activation of these processes with learning. This study provides the first evidence for a time- and learning-dependent property of neocortical KOR in facilitating acquisition and consolidation of associative memories, while elucidating an unexplored neocortical learning mechanism.
Ding, Guixia; Xu, Ying; Bai, Mi; Zhang, Yue; Jia, Zhanjun; Huang, Songming; Zhang, Aihua
Accumulating evidence suggests that loss of the renal tubular epithelial phenotype plays an important role in the pathogenesis of renal tubulointerstitial fibrosis. Systemic activation of peroxisome proliferator-activated receptor γ (PPAR-γ) has been shown to be protective against renal fibrosis, although the mechanisms are poorly understood. The present study aimed to define the role of renal tubular epithelium-targeted PPAR-γ in protection of the epithelial phenotype and the antagonism of renal fibrosis and to define the underlying mechanisms. In response to TGF-β1 challenge, PPAR-γ expression and activity in the renal proximal tubule epithelial cells (RPTECs) were significantly reduced, and the reduction was accompanied by decreased E-cadherin and elevated α-SMA, indicating a loss of the epithelial phenotype. Oxidative stress induced by TGF-β1 was shown to be attributed to the alteration of the epithelial phenotype and PPAR-γ inhibition. Activation of PPAR-γ by its agonists of rosiglitazone and 15d-PGJ2 or genetic overexpression of PPAR-γ prevented the loss of the epithelial phenotype induced by TGF-β1 in line with the inhibition of oxidative stress. To explore the role of PPAR-γ in renal tubular epithelial in antagonizing fibrogenesis, PPAR-γ was specifically deleted from RPTECs in mice. Following unilateral ureteral obstruction, the fibrosis was markedly deteriorated in mice with PPAR-γ invalidation in RPTECs. Treatment with rosiglitazone attenuated tubulointerstitial fibrosis and epithelial phenotype transition in WT but not proximal tubule PPAR-γ KO mice. Taken together, these findings identified an important role of renal tubular epithelium-targeted PPAR-γ in maintaining the normal epithelial phenotype and opposing fibrogenesis, possibly via antagonizing oxidative stress. PMID:27602490
Arai, H; Nakagawa, M; Tanada, K; Yamaguchi, H; Hirai, S
Histamine H2-antagonistic properties of the novel H2-antagonist T-593, (+-)-N-[2-hydroxy-2-(4-hydroxyphenyl)ethyl]-N'-[2- [[[5-(methylamino)methyl-2-furyl]methyl]thio]ethyl]-N"- (methylsulfonyl) guanidine were investigated on the histamine-induced positive chronotropic responses in isolated guinea pig right atria. T-593 at 3 x 10(-7)-3 x 10(-6) M suppressed the maximal responses of the histamine concentration-response curves in a concentration-dependent fashion, indicating that T-593 is an unsurmountable antagonist. The pD'2 values were 5.50 for T-593 and 5.61 for famotidine; and the IC50 values at 1 x 10(-5) M histamine were 1.05 x 10(-6) M for T-593, 1.59 x 10(-6) M for ranitidine and 1.67 x 10(-7) M for famotidine. T-593 is a racemic compound composed of two enantiomers, (-)-T-593 and (+)-T-593. The histamine H2-antagonistic activity of (-)-T-593 was 1.5-fold more potent than that of racemic T-593, but (+)-T-593 scarcely inhibited the histamine-induced positive chronotropic response. Histamine H2-antagonism by racemic T-593 was mainly attributed to (-)-T-593. Isoproterenol-induced positive chronotropic responses were not affected by T-593 even at 3 x 10(-5) M. Pretreatment of ranitidine for 10 min prior to application of T-593 protected H2-receptors from unsurmountable antagonism by T-593. Reversibility of H2-antagonism was determined every 1 hr after a 30-min treatment of H2-antagonists. T-593 inhibited the positive chronotropic responses for over 6 hr in contrast to fast recovery from inhibition by ranitidine or famotidine. This result showed that T-593 is a slowly dissociable, long-acting histamine H2-antagonist.
Chen, Rui; Li, Mi; Zhang, Yu; Zhou, Qian; Shu, Hong-Bing
The proinflammatory cytokine interleukin-1 (IL-1) signals via type I IL-1 receptor (IL-1RI) and IL-1 receptor accessory protein (IL1RAP), which leads to activation of the transcription factor NF-κB and induction of a range of downstream proteins involved in inflammatory and immune responses. Here, we identified the E3 ubiquitin ligase membrane-associated RING-CH (MARCH8) as a suppressor of IL-1β-induced NF-κB- and MAPK-activation pathways. Overexpression of MARCH8 inhibits IL-1β-induced NF-κB and MAPK activation, whereas knockdown of MARCH8 has the opposite effect. Mechanistically, MARCH8 interacts with IL1RAP and targets its Lys512 for K48-linked polyubiquitination and degradation. Our findings suggest that MARCH8-mediated polyubiquitination and degradation of IL1RAP is an important mechanism for negative regulation of IL-1β-induced signaling pathways.
Moraes, Carolina A; Santos, Gabriel; de Sampaio e Spohr, Tania Cristina Leite; D'Avila, Joana C; Lima, Flávia Regina Souza; Benjamim, Claudia Farias; Bozza, Fernando A; Gomes, Flávia Carvalho Alcantara
Recent clinical studies have shown that sepsis survivors may develop long-term cognitive impairments. The cellular and molecular mechanisms involved in these events are not well understood. This study investigated synaptic deficits in sepsis and the involvement of glial cells in this process. Septic animals showed memory impairment and reduced numbers of hippocampal and cortical excitatory synapses, identified by synaptophysin/PSD-95 co-localization, 9 days after disease onset. The behavioral deficits and synaptophysin/PSD-95 co-localization were rescued to normal levels within 30 days post-sepsis. Septic mice presented activation of microglia and reactive astrogliosis, which are hallmarks of brain injury and could be involved in the associated synaptic deficits. We treated neuronal cultures with conditioned medium derived from cultured astrocytes (ACM) and microglia (MCM) that were either non-stimulated or stimulated with lipopolysaccharide (LPS) to investigate the molecular mechanisms underlying synaptic deficits in sepsis. ACM and MCM increased the number of synapses between cortical neurons in vitro, and these effects were antagonized by LPS stimulation. LPS-MCM reduced the number of synapses by 50%, but LPS-ACM increased the number of synapses by 500%. Analysis of the composition of these conditioned media revealed increased levels of IL-1β in LPS-MCM. Furthermore, inhibition of IL-1β signaling through the addition of a soluble IL-1β receptor antagonist (IL-1 Ra) fully prevented the synaptic deficit induced by LPS-MCM. These results suggest that sepsis induces a transient synaptic deficit associated with memory impairments mediated by IL-1β secreted by activated microglia.
Nishimura, Kenji J; Ortiz, J Bryce; Conrad, Cheryl D
Chronic stress leads to a dysregulated inhibitory tone that could impact hippocampal-dependent spatial learning and memory. The present study examined whether spatial memory deficits resulting from chronic stress could be overcome by antagonizing the GABAA receptor, a prominent inhibitory receptor of GABA in the hippocampus. Young adult male Sprague-Dawley rats were chronically stressed (STR, wire mesh restraint, 6h/d/21d) or placed in a no-stress control group (CON). When chronic restraint ended, rats were tested on a 2-trial object placement (OP) task at a delay (3h) that would result in chance performance without intervention and then on novel object recognition (NOR) and the elevated plus maze (EPM) to assess non-spatial memory and anxiety profile. In CON rats, Bicuculline (BIC, 0, 0.25, 0.5mg/kg), a GABAA antagonist, injected 30min prior to training led to facilitated OP performance with 0.25 and 0.5mg/kg doses. In contrast, STR rats required BIC at the highest dose (0.5mg/kg) to improve OP performance. While overall object exploration was decreased by chronic stress, motivation or anxiety profile were unlikely to explain these results. These findings reveal two different dose response functions for BIC in control and chronically stressed rats, with the dose response function of BIC being shifted to the right for chronically stressed rats compared to controls in order to improve spatial memory. While the literature demonstrates that chronic stress disrupts hippocampal inhibitory tone, the current study reveals that a single injection to antagonize the GABAA receptor can restore hippocampal-dependent spatial memory in chronically stressed subjects. Copyright © 2017 Elsevier Inc. All rights reserved.
van Vulpen, Lize F D; Schutgens, Roger E G; Coeleveld, Katja; Alsema, Els C; Roosendaal, Goris; Mastbergen, Simon C; Lafeber, Floris P J G
Joint bleeding after (sports) trauma, after major joint surgery, or as seen in hemophilia in general leads to arthropathy. Joint degeneration is considered to result from the direct effects of blood components on cartilage and indirectly from synovial inflammation. Blood-provided proinflammatory cytokines trigger chondrocytes and induce the production of cartilage-degrading proteases. In the presence of erythrocyte-derived iron, cytokines stimulate radical formation in the vicinity of chondrocytes inducing apoptosis. To unravel the role of interleukin (IL) 1β and tumor necrosis factor (TNF) α in the pathogenesis of this blood-induced cartilage damage, the effect of antagonizing these cytokines was examined in human in vitro cultures. Addition of recombinant human IL-1β monoclonal antibody or IL-1 receptor antagonist resulted in a dose- and time-dependent protection of cartilage from blood-induced damage. In higher concentrations, almost complete normalization of cartilage matrix proteoglycan turnover was achieved. This was accompanied by a reduction in IL-1β and IL-6 production in whole blood cultures, whereas TNFα production remained unaffected. Interestingly, addition of a TNFα monoclonal antibody, although demonstrated to inhibit the direct (transient) effects of TNFα on cartilage, exhibited no effect on blood-induced (prolonged) cartilage damage. It is demonstrated that IL-1β is crucial in the development of blood-induced joint damage, whereas TNFα is not. This hierarchical position of IL-1β in blood-induced joint damage warrants studies on targeting IL-1β to potentially prevent joint degeneration after a joint bleed.
Viall, A K; Goodall, C P; Stang, B; Marley, K; Chappell, P E; Bracha, S
Serotonin receptor 1B (5HTR1B) traditionally exhibits anti-proliferative activity in osteoblasts. We examined the expression and function of 5HTR1B in the COS canine osteosarcoma cell line and normal canine osteoblasts. Equal levels of 5HTR1B gene and protein expression were found between normal and malignant osteoblasts. Treatment with serotonin enhanced viability of osteosarcoma cells but not normal osteoblasts. Challenge with the 5HTR1B agonist anpirtoline caused no change in cell viability. Rather incubation with the specific receptor antagonist SB224289 caused reduction in osteoblast viability, with this effect more substantial in osteosarcoma cells. Investigation of this inhibitory activity showed 5HTR1B antagonism induces apoptosis in malignant cells. Evaluation of phosphorylated levels of CREB and ERK, transcriptional regulators associated with serotonin receptor signalling in osteoblasts, revealed aberrant 5HTR1B signalling in COS. Our results confirm the presence of 5HTR1B in a canine osteosarcoma cell line and highlight this receptor as a possible novel therapeutic target.
Mora-Buch, R; Dotti, I; Planell, N; Calderón-Gómez, E; Jung, P; Masamunt, M C; Llach, J; Ricart, E; Batlle, E; Panés, J; Salas, A
Ulcerative colitis (UC) is a chronic intestinal inflammatory disease that may undergo periods of activity followed by remission. We aimed to identify the endogenous regulatory mechanisms that may promote disease remission. Transcriptional and protein analysis of the intestinal mucosa revealed that the IL-1 decoy receptor, interleukin-1 receptor type 2 (IL1R2), was upregulated in remission compared with active UC and controls. We identified epithelial cells as being responsible for increased IL-1R2 production during remission. Expression of IL1R2 was negatively regulated by Wnt/beta-catenin signals in colonic crypts or epithelial stem cell cultures; accordingly, epithelial stem cells upregulated IL-1R2 upon differentiation. Blocking IL-1R2 in isolated colonic crypt cultures of UC patients in remission and T-cell cultures stimulated with biopsy supernatant from UC patients in remission boosted IL-1β-dependent production of inflammation-related cytokines. Finally, IL1R2 transcription was significantly lower in patients that relapsed during a 1-year follow-up period compared with those in endoscopic remission. Collectively, our results reveal that the IL-1/IL-1R2 axis is differentially regulated in the remitting intestinal mucosa of UC patients. We hypothesize that IL-1R2 in the presence of low concentrations of IL-1β may act locally as a regulator of intestinal homeostasis. PMID:26530134
Nazarenko, Irina; Marhaba, Rachid; Reich, Eli; Voronov, Elena; Vitacolonna, Mario; Hildebrand, Dagmar; Elter, Elena; Rajasagi, Mohini; Apte, Ron N; Zöller, Margot
Analyzing the growth of fibrosarcoma lines derived from IL-1α-, IL-1β- , or IL-1αβ-knockout (-/-) mice in the immunocompetent host revealed that tumor-derived IL-1α and IL-1β exert strong and opposing effects on immune response induction, which prohibited the evaluation of a potential impact on tumorigenicity. Therefore, in vivo growth of IL-1-deficient tumor lines was evaluated in nu/nu mice and was compared with in vitro growth characteristics. All IL-1-deficient fibrosarcoma lines grow in immunocompromised mice. However, IL-1α-/-β-competent (comp) lines grow more aggressively, efficiently induce angiogenesis, and recruit inflammatory cells. Despite stronger tumorigenicity of IL-1βcomp lines, IL-1α strengthens anchorage-independent growth, but both IL-1α and IL-1β support drug resistance. Corresponding to the aggressive growth, IL-1βcomp cells display increased matrix adhesion, motility, and cable formation on matrigel, likely supported by elevated αv/β3 and matrix metalloroteinase expression. Recruitment of myeloid cells requires IL-1β but is regulated by IL-1α, because inflammatory chemokine and cytokine expression is stronger in IL-1α-/-βcomp than in IL-1wt lines. This regulatory effect of tumor-derived IL-1α is restricted to the tumor environment and does not affect systemic inflammatory response induction by tumor-derived IL-1β. Both sarcoma cell-derived IL-1α and IL-1β promote tumor growth. However, IL-1α exerts regulatory activity on the tumor cell-matrix cross-talk, and only IL-1β initiates systemic inflammation. PMID:18516292
Li, Qiming; Powell, Nicole; Zhang, Hao; Belevych, Natalya; Ching, San; Chen, Qun; Sheridan, John; Whitacre, Caroline; Quan, Ning
Interleukin-1 (IL-1) has been implicated in the disease progression of multiple sclerosis (MS). In the animal model of MS, experimental autoimmune encephalomyelitis (EAE), the induction of disease is significantly attenuated in mice lacking the type I IL-1 receptor (IL-1R1). In this study, we created a transgenic mouse (eIL-1R1 kd) in which IL-1R1 expression is knocked down specifically in endothelial cells. Induction of EAE in eIL-1R1 kd mice results in a decrease in incidence, severity and delayed onset of EAE. In addition, eIL-1R1 kd mice show significant decrease in VCAM-1 expression and diminished CD45+ and CD3+ infiltrating leukocytes in the spinal cord in animals challenged with EAE. Further, IL-1 and IL-23 stimulate IL-17 production by splenocytes from both wild type and the eIL-1R1 kd animals. Similarly, IL-1 and IL-23 synergistically stimulate splenocytes proliferation in these two strains of animals. After immunization with MOG79–96, although eIL-1R1 kd mice displayed greatly reduced clinical scores, their splenocytes produced IL-17 and proliferated in response to a second MOG challenge, similar to wild type animals. These findings indicate a critical role for endothelial IL-1R1 in mediating the pathogenesis of EAE, and describe a new model that can be used to study endothelial IL-1R1. PMID:20854891
Lazzaro, Stephanie C.; Hou, Mian; Cunha, Catarina; LeDoux, Joseph E.; Cain, Christopher K.
Norepinephrine receptors have been studied in emotion, memory, and attention. However, the role of alpha1-adrenergic receptors in fear conditioning, a major model of emotional learning, is poorly understood. We examined the effect of terazosin, an alpha1-adrenergic receptor antagonist, on cued fear conditioning. Systemic or intra-lateral amygdala…
Lazzaro, Stephanie C.; Hou, Mian; Cunha, Catarina; LeDoux, Joseph E.; Cain, Christopher K.
Norepinephrine receptors have been studied in emotion, memory, and attention. However, the role of alpha1-adrenergic receptors in fear conditioning, a major model of emotional learning, is poorly understood. We examined the effect of terazosin, an alpha1-adrenergic receptor antagonist, on cued fear conditioning. Systemic or intra-lateral amygdala…
Pavlowsky, Alice; Zanchi, Alice; Pallotto, Marta; Giustetto, Maurizio; Chelly, Jamel; Sala, Carlo; Billuart, Pierre
Interleukin-1-Receptor Accessory Protein Like 1 (IL1RAPL1) gene mutations are associated to cognitive impairment ranging from non-syndromic X-linked mental retardation to autism. Functionally IL1RAPL1 belongs to a novel family of Toll/IL-1 Receptors, but its ligand is unknown. In a recent study, we have shown that IL1RAPL1 is present in dendritic spine where it interacts with PSD-95, a major scaffold protein of excitatory post-synaptic density. We demonstrated that IL1RAPL1 regulates the synaptic localization of PSD-95 by controlling JNK (c-Jun terminal Kinase) activity and PSD-95 phosphorylation. Loss of IL1RAPL1 in mouse not only led to a reduction of excitatory synapses but also to specific deficits in hippocampal long-term synaptic plasticity. Here we report that activation of JNK pathway in neurons by Interleukin-1 (IL-1) is mediated by IL1RAPL1. The interaction of IL1RAPL1 with PSD-95 discloses a novel pathophysiological mechanism underlying cognitive impairment associated with alterations of the JNK pathway in response to IL-1 and leading to the mislocalization of PSD-95, that subsequently result in abnormal synaptic organization and function.
Kanakaraj, Palanisamy; Schafer, Peter H.; Cavender, Druie E.; Wu, Ying; Ngo, Karen; Grealish, Patrick F.; Wadsworth, Scott A.; Peterson, Per A.; Siekierka, John J.; Harris, Crafford A.; Fung-Leung, Wai-Ping
Interleukin (IL)-1 is a proinflammatory cytokine with pleiotropic effects in inflammation. IL-1 binding to its receptor triggers a cascade of signaling events, including activation of the stress-activated mitogen-activated protein (MAP) kinases, c-Jun NH2-terminal kinase (JNK) and p38 MAP kinase, as well as transcription factor nuclear factor κB (NF-κB). IL-1 signaling results in cellular responses through induction of inflammatory gene products such as IL-6. One of the earliest events in IL-1 signaling is the rapid interaction of IL-1 receptor–associated kinases, IRAK and IRAK-2, with the receptor complex. The relative roles of IRAK and IRAK-2 in IL-1 signaling pathways and subsequent cellular responses have not been previously determined. To evaluate the importance of IRAK in IL-1 signaling, IRAK-deficient mouse fibroblast cells were prepared and studied. Here we report that IL-1–mediated activation of JNK, p38, and NF-κB were all reduced in embryonic fibroblasts deficient in IRAK expression. In addition, IL-6 production in response to IL-1 was also dramatically reduced in IRAK-deficient embryonic fibroblasts and in skin fibroblasts prepared from IRAK-deficient mice. Our results demonstrate that IRAK plays an essential proximal role in coordinating multiple IL-1 signaling pathways for optimal induction of cellular responses. PMID:9625767
Genius, Just; Geiger, Johanna; Dölzer, Anna-Lena; Benninghoff, Jens; Giegling, Ina; Hartmann, Annette M; Möller, Hans-Jürgen; Rujescu, Dan
The psychotomimetic effects of N-methyl-D-aspartate (NMDA) receptor antagonists in healthy humans and their tendency to aggravate psychotic symptoms in schizophrenic patients have promoted the notion of altered glutamatergic neurotransmission in the pathogenesis of schizophrenia. The NMDA-receptor antagonist MK-801 was chronically administered to rats (0.02 mg/kg intraperitoneally for 14 days). In one subgroup the antipsychotic haloperidol (1 mg/kg) was employed as a rescue therapy. Glutamate distribution and 3-NT (3-nitrotyrosine) as a marker of oxidative stress were assessed by immunohistochemistry in tissue sections. In parallel, the effects of MK-801 and haloperidol were investigated in primary embryonal hippocampal cell cultures from rats. Chronic NMDA-R antagonism led to a marked increase of intracellular glutamate in the hippocampus (126.1 +/- 10.4% S.E.M of control; p=0.037), while 3-NT staining intensity remained unaltered. No differences were observed in extrahippocampal brain regions. Essentially these findings could be reproduced in vitro. The combined in vivo and in vitro strategy allowed us to assess the implications of disturbed glutamate metabolism for the occurrence of oxidative stress and to investigate the effects of antipsychotics. Our data suggest that oxidative stress plays a minor role in this model than previously suggested. The same applies to apoptosis. Moreover, the effect of haloperidol seems to be mediated through yet unidentified mechanisms, unrelated to D2-antagonism. These convergent lines of evidence indicate that further research should be focused on the glutamatergic system and that our animal model may provide a tool to explore the biology of schizophrenia.
de Bartolomeis, Andrea; Tomasetti, Carmine; Iasevoli, Felice
Dopamine partial agonism and functional selectivity have been innovative strategies in the pharmacological treatment of schizophrenia and mood disorders and have shifted the concept of dopamine modulation beyond the established approach of dopamine D2 receptor (D2R) antagonism. Despite the fact that aripiprazole was introduced in therapy more than 12 years ago, many questions are still unresolved regarding the complexity of the effects of this agent on signal transduction and intracellular pathways, in part linked to its pleiotropic receptor profile. The complexity of the mechanism of action has progressively shifted the conceptualization of this agent from partial agonism to functional selectivity. From the induction of early genes to modulation of scaffolding proteins and activation of transcription factors, aripiprazole has been shown to affect multiple cellular pathways and several cortical and subcortical neurotransmitter circuitries. Growing evidence shows that, beyond the consequences of D2R occupancy, aripiprazole has a unique neurobiology among available antipsychotics. The effect of chronic administration of aripiprazole on D2R affinity state and number has been especially highlighted, with relevant translational implications for long-term treatment of psychosis. The hypothesized effects of aripiprazole on cell-protective mechanisms and neurite growth, as well as the differential effects on intracellular pathways [i.e. extracellular signal-regulated kinase (ERK)] compared with full D2R antagonists, suggest further exploration of these targets by novel and future biased ligand compounds. This review aims to recapitulate the main neurobiological effects of aripiprazole and discuss the potential implications for upcoming improvements in schizophrenia therapy based on dopamine modulation beyond D2R antagonism.
Genius, Just; Geiger, Johanna; Dölzer, Anna-Lena; Benninghoff, Jens; Giegling, Ina; Hartmann, Annette M.; Möller, Hans-Jürgen; Rujescu, Dan
Background The psychotomimetic effects of N-methyl-D-aspartate (NMDA) receptor antagonists in healthy humans and their tendency to aggravate psychotic symptoms in schizophrenic patients have promoted the notion of altered glutamatergic neurotransmission in the pathogenesis of schizophrenia. Methods The NMDA-receptor antagonist MK-801 was chronically administered to rats (0.02 mg/kg intraperitoneally for 14 days). In one subgroup the antipsychotic haloperidol (1 mg/kg) was employed as a rescue therapy. Glutamate distribution and 3-NT (3-nitrotyrosine) as a marker of oxidative stress were assessed by immunohistochemistry in tissue sections. In parallel, the effects of MK-801 and haloperidol were investigated in primary embryonal hippocampal cell cultures from rats. Results Chronic NMDA-R antagonism led to a marked increase of intracellular glutamate in the hippocampus (126.1 +/− 10.4% S.E.M of control; p = 0.037), while 3-NT staining intensity remained unaltered. No differences were observed in extrahippocampal brain regions. Essentially these findings could be reproduced in vitro. Conclusion The combined in vivo and in vitro strategy allowed us to assess the implications of disturbed glutamate metabolism for the occurrence of oxidative stress and to investigate the effects of antipsychotics. Our data suggest that oxidative stress plays a minor role in this model than previously suggested. The same applies to apoptosis. Moreover, the effect of haloperidol seems to be mediated through yet unidentified mechanisms, unrelated to D2-antagonism. These convergent lines of evidence indicate that further research should be focused on the glutamatergic system and that our animal model may provide a tool to explore the biology of schizophrenia. PMID:23869202
Yoshida, Tomoyuki; Mishina, Masayoshi
IL1-receptor accessory protein-like 1 (IL1RAPL1), a member of interleukin-1/toll receptor (TIR) family, is responsible for a nonsyndromic form of mental retardation (MR). The zebrafish orthologue of mammalian IL1RAPL1, designated as Il1rapl1b, was expressed widely in the brain and in the olfactory placode. We employed an olfactory sensory neuron-specific gene manipulation system in combination with in vivo imaging of transparent zebrafish embryos to examine the functional role of Il1rapl1b in synaptic vesicle accumulation and subsequent morphological remodeling of axon terminals, the characteristic features of presynaptic differentiation of zebrafish olfactory sensory neurons during synapse formation. Antisense morpholino oligonucleotide against il1rapl1b suppressed both the synaptic vesicle accumulation and axon terminal remodeling. Consistently, the overexpression of Il1rapl1b stimulated synaptic vesicle accumulation. Swapping the carboxyl-terminal domain of Il1rapl1b with that of mouse IL-1 receptor accessory protein abolished the stimulatory effect. On the other hand, a substitution mutation in the TIR domain suppressed the morphological remodeling of axon terminals. Thus, the regulation of synaptic vesicle accumulation and subsequent morphological remodeling by Il1rapl1b appeared to be mediated by distinct domains. These results suggest that Il1rapl1b plays an important role in presynaptic differentiation during synapse formation.
Morrison, Janna L; Sood, Sandeep; Liu, Hattie; Park, Eileen; Nolan, Philip; Horner, Richard L
The pharyngeal muscles, such as the genioglossus (GG) muscle of the tongue, are important for effective lung ventilation since they maintain an open airspace. Rapid-eye-movement (REM) sleep, however, recruits powerful neural mechanisms that can abolish GG activity, even during strong reflex respiratory stimulation by elevated CO2. In vitro studies have demonstrated the presence of GABAA receptors on hypoglossal motoneurons, and these and other data have led to the speculation that GABAA mechanisms may contribute to the suppression of hypoglossal motor outflow to the GG muscle in REM sleep. We have developed an animal model that allows us to chronically manipulate neurotransmission at the hypoglossal motor nucleus using microdialysis across natural sleep-wake states in rats. The present study tests the hypothesis that microdialysis perfusion of the GABAA receptor antagonist bicuculline into the hypoglossal motor nucleus will prevent the suppression of GG muscle activity in REM sleep during both room-air and CO2-stimulated breathing. Ten rats were implanted with electroencephalogram and neck muscle electrodes to record sleep-wake states, and GG and diaphragm electrodes for respiratory muscle recording. Microdialysis probes were implanted into the hypoglossal motor nucleus for perfusion of artificial cerebrospinal fluid (ACSF) or 100 μm bicuculline during room-air and CO2-stimulated breathing (7 % inspired CO2). GABAA receptor antagonism at the hypoglossal motor nucleus increased respiratory-related GG activity during both room-air (P = 0.01) and CO2-stimulated breathing (P = 0.007), indicating a background inhibitory GABA tone. However, the effects of bicuculline on GG activity depended on the prevailing sleep-wake state (P < 0.005), with bicuculline increasing GG activity in non-REM (NREM) sleep and wakefulness both in room air and hypercapnia (P < 0.01), but GG activity was effectively abolished in those REM periods without phasic twitches in the GG muscle. This
Hiranita, Takato; Hong, Weimin C; Kopajtic, Theresa; Katz, Jonathan L
Several N-substituted benztropine (BZT) analogs are atypical dopamine transport inhibitors as they have affinity for the dopamine transporter (DAT) but have minimal cocaine-like pharmacologic effects and can block numerous effects of cocaine, including its self-administration. Among these compounds, N-methyl (AHN1-055), N-allyl (AHN2-005), and N-butyl (JHW007) analogs of 3α-[bis(4'-fluorophenyl)methoxy]-tropane were more potent in antagonizing self-administration of cocaine and d-methamphetamine than in decreasing food-maintained responding. The antagonism of cocaine self-administration (0.03-1.0 mg/kg per injection) with the above BZT analogs was reproduced in the present study. Further, the stimulant-antagonist effects resembled previously reported effects of pretreatments with combinations of standard DAT inhibitors and σ1-receptor (σ1R) antagonists. Therefore, the present study examined binding of the BZT analogs to σRs, as well as their in vivo σR antagonist effects. Each of the BZT analogs displaced radiolabeled σR ligands with nanomolar affinity. Further, self-administration of the σR agonist DTG (0.1-3.2 mg/kg/injection) was dose dependently blocked by AHN2-005 and JHW007 but potentiated by AHN1-055. In contrast, none of the BZT analogs that were active against DTG self-administration was active against the self-administration of agonists at dopamine D1-like [R(+)-SKF 81297, (±)-SKF 82958 (0.00032-0.01 mg/kg per injection each)], D2-like [R(-)-NPA (0.0001-0.0032 mg/kg per injection), (-)-quinpirole (0.0032-0.1 mg/kg per injection)], or μ-opioid (remifentanil, 0.0001-0.0032 mg/kg per injection) receptors. The present results indicate that behavioral antagonist effects of the N-substituted BZT analogs are specific for abused drugs acting at the DAT and further suggest that σR antagonism contributes to those actions. U.S. Government work not protected by U.S. copyright.
Bétry, Cécile; Pehrson, Alan L; Etiévant, Adeline; Ebert, Bjarke; Sánchez, Connie; Haddjeri, Nasser
The therapeutic effect of current antidepressant drugs appears after several weeks of treatment and a significant number of patients do not respond to treatment. Here, we report the effects of the multi-modal antidepressant vortioxetine (Lu AA21004), a 5-HT(3) and 5-HT(7) receptor antagonist, 5-HT(1B) receptor partial agonist, 5-HT(1A) receptor agonist and 5-HT transporter (SERT) inhibitor, on rat 5-HT neurotransmission. Using in vivo electrophysiological recordings in the dorsal raphe nucleus of anaesthetized rats, we assessed the acute and subchronic effects of vortioxetine and/or the selective 5-HT(3) receptor agonist, SR57227 or the selective 5-HT(1A) receptor agonist flesinoxan, on 5-HT neuronal firing activity. Using ex-vivo autoradiography, we correlated SERT occupancy and presumed 5-HT firing activity. The selective serotonin reuptake inhibitor, fluoxetine, was used as comparator. Importantly, the recovery of 5-HT neuronal firing was achieved after 1 d with vortioxetine and 14 d with fluoxetine. SR57227 delayed this recovery. In contrast, vortioxetine failed to alter the reducing action of 3 d treatment of flesinoxan. Acute dosing of vortioxetine inhibited neuronal firing activity more potently than fluoxetine. SR57227 prevented the suppressant effect of vortioxetine, but not of fluoxetine. In contrast, flesinoxan failed to modify the suppressant effect of vortioxetine acutely administered. Differently to fluoxetine, vortioxetine suppressed neuronal firing without saturating occupancy at the SERT. Vortioxetine produced a markedly faster recovery of 5-HT neuronal firing than fluoxetine. This is at least partly due to 5-HT(3) receptor antagonism of vortioxetine in association with its reduced SERT occupancy.
Popoli, Patrizia; Minghetti, Luisa; Tebano, Maria Teresa; Pintor, Annita; Domenici, Maria Rosaria; Massotti, Marino
Adenosine A2A receptor antagonists are regarded as potential neuroprotective drugs, although the mechanisms underlying their effects remain to be elucidated. In this review, quinolinic acid (QA)-induced striatal toxicity was used as a tool to investigate the mechanisms of the neuroprotective effects of A2A receptor antagonists. After having examined the effects of selective A2A receptor antagonists toward different mechanisms of QA toxicity, we conclude that (1) the effect elicited by A2A receptor blockade on QA-induced glutamate outflow may be one of the mechanisms of the neuroprotective activity of A2A receptor antagonists; (2) A2A receptor antagonists have a potentially worsening influence on QA-dependent NMDA receptor activation; and (3) the ability of A2A receptor antagonists to prevent QA-induced lipid peroxidation does not correlate with the neuroprotective effects. These results suggest that A2A receptor antagonists may have either potentially beneficial or detrimental influence in models of neurodegeneration that are mainly due to increased glutamate levels or enhanced sensitivity of NMDA receptors, respectively.
Marcos, B; Chuang, T T; Gil-Bea, F J; Ramirez, M J
Background and purpose: The beneficial effect of 5-HT6 receptor antagonism in cognition remains controversial. This study has been undertaken to reassess the cognition enhancing properties of acute vs subchronic treatment with the selective 5-HT6 receptor antagonist SB-271046 in unimpaired rats, as well as against scopolamine (cholinergic-) or MK-801 (glutamatergic-mediated) deficits. Experimental approach: The Morris water maze was used, measuring behaviour acquisition and retention, and swim speed. Other behavioural measures included yawning and motor activity. SB-271046 was given acutely before each trial or subchronically for 7 days before the trials. The AChE inhibitor galanthamine was also used alone or in combination with SB-271046. Key results: Subchronic treatment with SB-271046 improved acquisition in the Morris water maze, while the acute treatment only improved retention. Neither acute nor subchronic SB-271046 treatment reversed scopolamine-induced learning deficits. MK-801 induced learning impairment associated with a behavioural syndrome, reversed by acute, but not subchronic, SB-271046 treatment. Interestingly, combined treatment with galanthamine and SB-271046 reversed the scopolamine- or MK-801-induced learning impairments. Subchronic treatment with SB-271046 did not modify motor activity or the increased number of yawns, a cholinergic-mediated behaviour, induced by single administration of SB-271046. Conclusions and implications: These data suggest a potential therapeutic role of 5-HT6 receptor antagonists such as SB-271046, alone or in combination with galanthamine, in the treatment of cognitive dysfunction, such as those seen in Alzheimer's disease and schizophrenia. PMID:18622410
Noh, Ji-Hyun; Gwag, Byoung-Joo; Chung, Jun-Mo
Sulfasalazine (SULFA), of anti-inflammatory drugs, shows a protective action against NMDA-induced neuronal toxicity. Here, we used an electrophysiological study of the pharmacological effects of SULFA on NMDA receptors to examine the molecular mechanisms underlying the neuroprotective role of SULFA. The drug acted as a typical noncompetitive inhibitor with neither agonist- nor use-dependency, and antagonized NMDA-evoked responses in a voltage-independent manner, suggesting that SULFA is not an open channel blocker. Noise and single channel analyses showed that SULFA-blocked NMDA responses by reducing the number of NMDA channels available for activation, and also reduced the channel open probability without changing single channel conductance. Moreover, SULFA accelerated NMDA desensitization without affecting the affinity of the receptor for NMDA or glutamate. Taken together, these data indicate that SULFA blocks the NMDA response by reducing the number of NMDA channels available for activation. This appears to occur via a SULFA-induced decrease in the channel open probability, and a concomitant acceleration of the desensitization response, which is likely associated with a reduced affinity for glycine. SULFA indeed decreased the glycine-potentiated NMDA response without binding directly to the glycine site. Our results suggest that SULFA acts as a noncompetitive NMDA receptor antagonist with an allosteric glycine modulation.
Ågerstam, Helena; Hansen, Nils; von Palffy, Sofia; Sandén, Carl; Reckzeh, Kristian; Karlsson, Christine; Lilljebjörn, Henrik; Landberg, Niklas; Askmyr, Maria; Högberg, Carl; Rissler, Marianne; Porkka, Kimmo; Wadenvik, Hans; Mustjoki, Satu; Richter, Johan; Järås, Marcus; Fioretos, Thoas
Chronic myeloid leukemia (CML) is currently treated with tyrosine kinase inhibitors, but these do not effectively eliminate the CML stem cells. As a consequence, CML stem cells persist and cause relapse in most patients upon drug discontinuation. Furthermore, no effective therapy exists for the advanced stages of the disease. Interleukin-1 receptor accessory protein (IL1RAP; IL1R3) is a coreceptor of interleukin-1 receptor type 1 and has been found upregulated on CML stem cells. Here, we show that primitive (CD34(+)CD38(-)) CML cells, in contrast to corresponding normal cells, express a functional interleukin-1 (IL-1) receptor complex and respond with NF-κB activation and marked proliferation in response to IL-1. IL1RAP antibodies that inhibit IL-1 signaling could block these effects. In vivo administration of IL1RAP antibodies in mice transplanted with chronic and blast phase CML cells resulted in therapeutic effects mediated by murine effector cells. These results provide novel insights into the role of IL1RAP in CML and a strong rationale for the development of an IL1RAP antibody therapy to target residual CML stem cells. © 2016 by The American Society of Hematology.
Andersson, John; Hardwick, Donna; Bebris, Lolita; Illei, Gabor G.
Although adoptive transfer of regulatory T cells (Foxp3+ Tregs) has proven to be efficacious in the prevention and treatment of autoimmune diseases and graft-versus-host disease in rodents, a major obstacle for the use of Treg immunotherapy in humans is the difficulty of obtaining a highly purified preparation after ex vivo expansion. We have identified latency-associated peptide (LAP) and IL-1 receptor type I and II (CD121a/CD121b) as unique cell-surface markers that distinguish activated Tregs from activated FOXP3− and FOXP3+ non-Tregs. We show that it is feasible to sort expanded FOXP3+ Tregs from non-Tregs with the use of techniques for magnetic bead cell separation based on expression of these 3 markers. After separation, the final product contains greater than 90% fully functional FOXP3+ Tregs. This novel protocol should facilitate the purification of Tregs for both cell-based therapies as well as detailed studies of human Treg function in health and disease. PMID:19299332
Lever, John R; Miller, Dennis K; Green, Caroline L; Fergason-Cantrell, Emily A; Watkinson, Lisa D; Carmack, Terry L; Fan, Kuo-Hsien; Lever, Susan Z
Cocaine functions, in part, through agonist actions at sigma-1 (σ1 ) receptors, while roles played by sigma-2 (σ2 ) receptors are less established. Attempts to discriminate σ2 receptor-mediated effects of cocaine in locomotor hyperactivity assays have been hampered by the lack of potent and selective antagonists. Certain tetrahydroisoquinolinyl benzamides display high σ2 receptor affinity, and excellent selectivity for binding to σ2 over σ1 receptors. The behavioral properties of this structural class of σ ligands have not yet been investigated. The present study evaluated 5-bromo-N-[4-(6,7-dimethoxy-3,4-dihydro-1H-isoquinolin-2-yl)-butyl)]-2,3-dimethoxy-benzamide, 1, a ligand shown by others to bind preferentially to σ2 over σ1 receptors, as well as dopamine D2 and D3 sites. First, we determined binding to monoamine transporters and opioid receptors, and noted 57-fold selectivity for σ2 receptors over the serotonin transporter, and >800-fold selectivity for σ2 receptors over the other sites tested. We then examined 1 in locomotor activity studies using male CD-1® mice, and saw no alteration of basal activity at doses up to 31.6 µmol/kg. Cocaine produced a fivefold increase in locomotor activity, which was attenuated by 66% upon pretreatment of mice with 1 at 31.6 µmol/kg. In vivo radioligand binding studies also were performed, and showed no occupancy of σ1 receptors or the dopamine transporter by 1, or its possible metabolites, at the 31.6 µmol/kg dose. Thus, ligand 1 profiles behaviorally as a σ2 receptor-selective antagonist that is able to counteract cocaine's motor stimulatory effects. Copyright © 2013 Wiley Periodicals, Inc.
Husbands, Stephen M; Neilan, Claire L; Broadbear, Jillian; Grundt, Peter; Breeden, Simon; Aceto, Mario D; Woods, James H; Lewis, John W; Traynor, John R
In the search for opioid agonists with delayed antagonist actions as potential treatments for substance abuse, the bridged morphinan BU74 (17-cyclopropylmethyl-3-hydroxy-[5beta,7beta,3',5']-pyrrolidino-2'[S]-phenyl-7alpha-methyl-6,14-endoetheno morphinan) (3f) was synthesized. In isolated tissue and [35S]GTPgammaS opioid receptor functional assays BU74 was shown to be a potent long-lasting kappa opioid receptor agonist, delta opioid receptor partial agonist and mu opioid receptor antagonist. In antinociceptive tests in the mouse, BU74 showed high efficacy and potent kappa opioid receptor agonism. When its agonist action had waned BU74 became an antagonist of kappa and mu opioid receptor agonists in the tail flick assay and of delta, kappa and mu opioid receptor agonists in the acetic acid writhing assay. The slow onset, long-duration kappa opioid receptor agonist effects of BU74 suggests that it could be a lead compound for the discovery of a treatment for cocaine abuse.
Lelas, Snjezana; Li, Yu-Wen; Wallace-Boone, Tanya L; Taber, Matthew T; Newton, Amy E; Pieschl, Rick L; Davis, Carl D; Molski, Thaddeus F; Newberry, Kimberly S; Parker, Michael F; Gillman, Kevin W; Bronson, Joanne J; Macor, John E; Lodge, Nicholas J
The known interactions between the serotonergic and neurokinin systems suggest that serotonin reuptake inhibitor (SSRIs) efficacy may be improved by neurokinin-1 receptor (NK1R) antagonism. In the current studies combination of a subeffective dose of an SSRI (0.3 mg/kg fluoxetine or 0.03 mg/kg citalopram) with a subeffective dose of an NK1R antagonist (0.3 mg/kg aprepitant or 1 mg/kg CP-122,721) produced efficacy in the gerbil forced swim test (FST). Serotonin transporter (SERT) occupancy produced by 1 mg/kg fluoxetine (lowest efficacious dose) was 52 ± 5% and was reduced to 29 ± 4% at 0.3 mg/kg, a dose that was efficacious in combination with 0.3 mg/kg aprepitant or 1 mg/kg CP-122,721; the corresponding NK1R occupancies were 79 ± 4% and 61 ± 4% for aprepitant and CP-122,721, respectively. For citalopram, SERT occupancy at the lowest efficacious dose (0.1 mg/kg) was 50 ± 4% and was reduced to 20 ± 5% at 0.03 mg/kg, a dose that was efficacious when combined with aprepitant (0.3 mg/kg). Aprepitant (10 mg/kg) augmented the serotonin elevation produced by fluoxetine (1 or 10 mg/kg) in the gerbil prefrontal cortex; i.e. NK1R antagonism can modulate serotonin responses. A novel orally-available dual-acting NK1R antagonist/SERT inhibitor BMS-795176 is described; gerbil Ki = 1.4 and 1 nM at NK1R and SERT, respectively. BMS-795176 was efficacious in the gerbil FST; efficacy was observed with 35 ± 3% SERT occupancy and 73 ± 3% NK1R occupancy. The interaction between NK1R antagonism and SERT inhibition to lower the SERT occupancy required for antidepressant-like efficacy suggests that BMS-795176 has the potential to improve efficacy with a reduction in SSRI-associated side effects.
Ortiz, Rudy M.; Mamalis, Andrew; Navar, L. Gabriel
Background Elevated C-reactive protein (CRP) may contribute to elevated arterial pressure in Ang II-dependent hypertension. However, the in vivo effects of Ang II and of mineralocorticoid receptor (MR) antagonism on CRP during Ang II-dependent hypertension have not been examined. In addition, urinary CRP excretion as a method to monitor the progression of Ang II-induced inflammation has not been evaluated. Methods Urine samples were collected from three groups (n = 10/group) of rats: 1) normotensive control, 2) angiotensin II infused (Ang II; 60 ng/min), and 3) Ang II + eplerenone (epl; 25 mg/d). A diet containing epl (0.1 %) was provided after 1 week of Ang II infusion. Results After 28 d, Ang II increased SBP from 136 ± 5 to 207 ± 8 mmHg; this response in SBP was not altered following MR antagonism (215 ± 6 mmHg). Ang II-infusion increased plasma CRP from 14 ± 2 to 26 ± 3 μg/mL and increased urinary CRP excretion nearly 8-fold (143 ± 26 vs 1102 ± 115 ng/d). Treatment with eplerenone reduced plasma CRP by 25 % and urinary immunoreactive CRP (irCRP) by 34 % in Ang II-infused rats suggesting that aldosterone contributes to the CRP-associated inflammatory response in Ang II-dependent hypertension. Conclusions The increase in SBP preceded the increase in irCRP excretion by at least 4 days suggesting that CRP does not significantly contribute to increased arterial blood pressure in Ang II-dependent hypertension. The blockade of MR reduced plasma CRP and urinary irCRP excretion demonstrating the contribution of aldosterone to the Ang II-induced generation of CRP. Furthermore, urinary CRP may serve as a non-invasive index for monitoring cardiovascular inflammation during hypertension. PMID:20161115
Yang, Yu-Lin; Liu, Yi-Shiuan; Chuang, Lea-Yea; Guh, Jinn-Yuh; Lee, Tao-Chen; Liao, Tung-Nan; Hung, Min-Yuan; Chiang, Tai-An
TGF-beta is a therapeutic target for renal fibrosis. Scientists have long sought ways to antagonize TGF-beta to ameliorate diabetic nephropathy. Bone morphogenetic protein (BMP-2) is a member of the TGF-beta superfamily and is highly regulated in the kidney. Thus, the role of BMP-2 was investigated in NRK-49F cells (rat fibroblasts). We showed that TGF-beta1 induces an increase in fibronectin. Treatment with exogenous BMP-2 or pCMV-BMP-2 significantly reversed the TGF-beta1-induced increase in fibronectin concomitant with a significant decrease in type I TGF-beta receptors (TGF-beta RI). Moreover, BMP-2 significantly shortened the half-life of TGF-beta RI. These results are related to proteosomal activation because MG132, a proteasome inhibitor, abolished BMP-2-mediated degradation of TGF-beta RI. This was confirmed because BMP-2 time course dependently enhanced the ubiquitination level of TGF-beta RI. In addition, Smads would seem to be involved in the interaction of BMP-2 and TGF-beta. We demonstrated that BMP-2 significantly reversed the TGF-beta1-induced increase in pSmad2/3 and reversed the TGF-beta1-induced decrease in inhibitory Smad7. Most importantly, Smad7 small interfering RNA abolished the BMP-2-induced decrease in TGF-beta RI. We evaluated the clinical efficacy of BMP-2 using unilateral ureteral obstruction rats. BMP-2 was administered ip for 7 d. In the unilateral ureteral obstruction kidneys, interstitial fibrosis was prominent. However, treatment with BMP-2 dramatically reduced Masson's trichrome staining (collagen) in the interstitial and tubular areas of the kidneys concomitantly with a reduction in TGF-beta RI. These results suggest that BMP-2 acts as a novel fibrosis antagonizing cytokine partly by down-regulating TGF-beta RI and Smads.
Chen, Wen-Ting; Huang, Wen-Yang; Chen, Ting; Salawu, Emmanuel Oluwatobi; Wang, Dongli; Lee, Yi-Zong; Chang, Yuan-Yu; Yang, Lee-Wei; Sue, Shih-Che; Wang, Xinquan; Yin, Hsien-Sheng
Receptor-binding and subsequent signal-activation of interleukin-1 beta (IL-1β) are essential to immune and proinflammatory responses. We mutated 12 residues to identify sites important for biological activity and/or receptor binding. Four of these mutants with mutations in loop 9 (T117A, E118K, E118A, E118R) displayed significantly reduced biological activity. Neither T117A nor E118K mutants substantially affected receptor binding, whereas both mutants lack the IL-1β signaling in vitro but can antagonize wild-type (WT) IL-1β. Crystal structures of T117A, E118A, and E118K revealed that the secondary structure or surface charge of loop 9 is dramatically altered compared with that of wild-type chicken IL-1β. Molecular dynamics simulations of IL-1β bound to its receptor (IL-1RI) and receptor accessory protein (IL-1RAcP) revealed that loop 9 lies in a pocket that is formed at the IL-1RI/IL-1RAcP interface. This pocket is also observed in the human ternary structure. The conformations of above mutants in loop 9 may disrupt structural packing and therefore the stability in a chicken IL-1β/IL-1RI/IL-1RAcP signaling complex. We identify the hot spots in IL-1β that are essential to immune responses and elucidate a mechanism by which IL-1β activity can be inhibited. These findings should aid in the development of new therapeutics that neutralize IL-1 activity. PMID:27278931
Lopes, Cristiane; Pereira, Edna F R; Wu, Hui-Qiu; Purushottamachar, Puranik; Njar, Vincent; Schwarcz, Robert; Albuquerque, Edson X
Galantamine, a drug used to treat Alzheimer's disease, is a nicotinic allosteric potentiating ligand, and kynurenic acid (KYNA), a neuroactive metabolite of the kynurenine pathway, is an endogenous noncompetitive inhibitor of alpha7* nicotinic receptors (nAChRs) [the asterisk next to the nAChR subunit is intended to indicate that the exact subunit composition of the receptor is not known (Pharmacol Rev 51:397-401, 1999)]. Here, possible interactions between KYNA and galantamine at alpha7* nAChRs were examined in vitro and in vivo. In the presence of tetrodotoxin (TTX), approximately 85% of cultured hippocampal neurons responded to choline (0.3-30 mM) with alpha7* nAChR-subserved whole-cell (type IA) currents. In the absence of TTX and in the presence of glutamate receptor antagonists, choline triggered inhibitory postsynaptic currents (IPSCs) by activating alpha7* nAChRs on GABAergic neurons synapsing onto the neurons under study. Galantamine (1-10 microM) potentiated, whereas KYNA (10 nM-1 mM) inhibited, choline-triggered responses. Galantamine (1 microM), applied before KYNA, shifted to the right the concentration-response relationship for KYNA to inhibit type IA currents, increasing the IC(50) of KYNA from 13.9 +/- 8.3 to 271 +/- 131 microM. Galantamine, applied before or after KYNA, antagonized inhibition of choline-triggered IPSCs by KYNA. Local infusion of KYNA (100 nM) in the rat striatum reduced extracellular dopamine levels in vivo. This effect resulted from alpha7* nAChR inhibition and was blocked by coapplied galantamine (1-5 microM). It is concluded that galantamine competitively antagonizes the actions of KYNA on alpha7* nAChRs. Reducing alpha7* nAChR inhibition by endogenous KYNA may be an important determinant of the effectiveness of galantamine in neurological and psychiatric disorders associated with decreased alpha7* nAChR activity in the brain.
Musto, Alberto E.; Samii, Mark
Purpose Temporal lobe epilepsy is associated with the inflammatory process related to the basic mechanisms that lead to seizure susceptibility and brain damage. Platelet-activating factor (PAF), a potent, short-lived phospholipid mediator of inflammation participates in physiological signaling in the brain. However, after seizures PAF accumulates in the brain and activates intracellular signaling related with inflammation-mediated excitotoxicity and hippocampal hyperexcitability. The objective of this study is to evaluate the effect of PAF antagonism on hippocampal hyperexcitability, seizure susceptibility and neuroprotection using the kindling paradigm and pilocarpine-induced seizure damage models. Methods The PAF antagonist, LAU-0901 (60 mg/kg, i.p.), or vehicle was administrated each day of kindling or daily during the four weeks after status epilepticus (SE). We analyzed seizure severity, electrical activity, cellular damage and inflammation in the hippocampi of both treated groups. Results LAU-0901 limits the progression of kindling and attenuates seizure susceptibility one week after the kindling procedure. Also, under the seizure-damage conditions studied here, we observed that LAU-0901 induces hippocampal neuroprotection and limits somatostatin interneuronal cell loss and inflammation. Discussion Our results indicate that modulation of PAF over-activity attenuates seizure susceptibility, hippocampal hyperexcitability and neuroinflammation. PMID:21204830
Cheng, Kang; Wu, Tsuei-Ju; Wu, Kenneth K; Sturino, Claudio; Metters, Kathleen; Gottesdiener, Keith; Wright, Samuel D; Wang, Zhaoyin; O'Neill, Gary; Lai, Eseng; Waters, M Gerard
Nicotinic acid (NA) is commonly used to treat dyslipidemia, but it elicits an adverse effect, termed flushing, which consists of cutaneous vasodilation with associated discomfort. An animal model of NA-induced flushing has been established in mice. As in humans, NA stimulated vasodilation in a dose-dependent manner, was associated with an increase of the vasodilatory prostaglandin (PG) D2 in plasma and could be blocked by pretreatment with aspirin. Two PGD2 receptors have been identified: PGD2 receptor 1 (DP1, also called DP) and PGD2 receptor 2 (DP2, sometimes termed CRTH2). DP2 does not mediate NA-induced vasodilation; the DP2-specific agonist DK-PGD2 (13,14-dihydro-15-keto-PGD2) did not induce cutaneous vasodilation, and DP2-/- mice had a normal vasodilatory response to NA. By contrast, BW245C, a DP1-selective agonist, induced vasodilation in mice, and MK-0524, a DP1-selective antagonist, blocked both PGD2- and NA-induced vasodilation. NA-induced vasodilation was also studied in DP1+/+, DP1+/-, and DP1-/- mice; although NA-induced vasodilation depended almost completely on DP1 in female mice, it depended only partially on DP1 in male mice. The residual NA-induced vasodilation in male DP-/- mice was aspirin-sensitive. Thus, in the mouse, DP1 appears to be an important component involved in NA-induced vasodilation, but other cyclooxygenase-dependent mechanisms also may be involved. A clinical study in healthy men and women demonstrated that treatment with MK-0524 reduced the symptoms of flushing and the increase in skin perfusion after the administration of NA. These studies suggest that DP1 receptor antagonism may be an effective means to suppress NA-induced flushing in humans.
Cheng, Kang; Wu, Tsuei-Ju; Wu, Kenneth K.; Sturino, Claudio; Metters, Kathleen; Gottesdiener, Keith; Wright, Samuel D.; Wang, Zhaoyin; O’Neill, Gary; Lai, Eseng; Waters, M. Gerard
Nicotinic acid (NA) is commonly used to treat dyslipidemia, but it elicits an adverse effect, termed flushing, which consists of cutaneous vasodilation with associated discomfort. An animal model of NA-induced flushing has been established in mice. As in humans, NA stimulated vasodilation in a dose-dependent manner, was associated with an increase of the vasodilatory prostaglandin (PG) D2 in plasma and could be blocked by pretreatment with aspirin. Two PGD2 receptors have been identified: PGD2 receptor 1 (DP1, also called DP) and PGD2 receptor 2 (DP2, sometimes termed CRTH2). DP2 does not mediate NA-induced vasodilation; the DP2-specific agonist DK-PGD2 (13,14-dihydro-15-keto-PGD2) did not induce cutaneous vasodilation, and DP2−/− mice had a normal vasodilatory response to NA. By contrast, BW245C, a DP1-selective agonist, induced vasodilation in mice, and MK-0524, a DP1-selective antagonist, blocked both PGD2- and NA-induced vasodilation. NA-induced vasodilation was also studied in DP1+/+, DP1+/−, and DP1−/− mice; although NA-induced vasodilation depended almost completely on DP1 in female mice, it depended only partially on DP1 in male mice. The residual NA-induced vasodilation in male DP−/− mice was aspirin-sensitive. Thus, in the mouse, DP1 appears to be an important component involved in NA-induced vasodilation, but other cyclooxygenase-dependent mechanisms also may be involved. A clinical study in healthy men and women demonstrated that treatment with MK-0524 reduced the symptoms of flushing and the increase in skin perfusion after the administration of NA. These studies suggest that DP1 receptor antagonism may be an effective means to suppress NA-induced flushing in humans. PMID:16617107
Rodríguez-Romo, Roxana; Benítez, Kenia; Barrera-Chimal, Jonatan; Pérez-Villalva, Rosalba; Gómez, Arturo; Aguilar-León, Diana; Rangel-Santiago, Jesús F; Huerta, Sara; Gamba, Gerardo; Uribe, Norma; Bobadilla, Norma A
Despite clinical recovery of patients from an episode of acute kidney injury (AKI), progression to chronic kidney disease (CKD) is possible on long-term follow-up. However, mechanisms of this are poorly understood. Here, we determine whether activation of angiotensin-II type 1 receptors during AKI triggers maladaptive mechanisms that lead to CKD. Nine months after AKI, male Wistar rats develop CKD characterized by renal dysfunction, proteinuria, renal hypertrophy, glomerulosclerosis, tubular atrophy, and tubulointerstitial fibrosis. Renal injury was associated with increased oxidative stress, inflammation, α-smooth muscle actin expression, and activation of transforming growth factor β; the latter mainly found in epithelial cells. Although administration of losartan prior to the initial ischemic insult did not prevent or reduce AKI severity, it effectively prevented eventual CKD. Three days after AKI, renal dysfunction, tubular structural injury, and elevation of urinary biomarkers were present. While the losartan group had similar early renal injury, renal perfusion was completely restored as early as day 3 postischemia. Further, there was increased vascular endothelial growth factor expression and an early activation of hypoxia-inducible factor 1 α, a transcription factor that regulates expression of many genes that help reduce renal injury. Thus, AT1 receptor antagonism prior to ischemia prevented AKI to CKD transition by improving early renal blood flow recovery, lesser inflammation, and increased hypoxia-inducible factor 1 α activity.
Cotton, Robert B.; Shah, Lisa P.; Poole, Stanley D.; Ehinger, Noah J.; Brown, Naoko; Shelton, Elaine L.; Slaughter, James C.; Baldwin, H. Scott; Paria, Bibhash C.; Reese, Jeff
Persistent patency of the ductus arteriosus (PDA) is a common problem in preterm infants. The antacid cimetidine is a potent antagonist of the H2 histamine receptor but also inhibits certain cytochrome P450 enzymes (CYPs), which may affect DA patency. We examined whether cimetidine contributes to PDA and is mediated by CYP inhibition rather than H2 blockade. Analysis of a clinical trial to prevent lung injury in premature infants revealed a significant association between cimetidine treatment and PDA. Cimetidine and ranitidine, both CYP inhibitors as well as H2 blockers, caused relaxation of the term and preterm mouse DA. CYP enzymes that are inhibited by cimetidine were expressed in DA subendothelial smooth muscle. The selective CYP3A inhibitor ketoconazole induced greater DA relaxation than cimetidine, whereas famotidine and other H2 antagonists with less CYP inhibitory effects caused less dilation. Histamine receptors were developmentally regulated and localized in DA smooth muscle. However, cimetidine caused DA relaxation in histamine-deficient mice, consistent with CYP inhibition, not H2 antagonism, as the mechanism for PDA. Oxygen-induced DA constriction was inhibited by both cimetidine and famotidine. These studies show that antacids and other compounds with CYP inhibitory properties pose a significant and previously unrecognized risk for PDA in critically ill newborn infants. PMID:23454087
Cotton, Robert B; Shah, Lisa P; Poole, Stanley D; Ehinger, Noah J; Brown, Naoko; Shelton, Elaine L; Slaughter, James C; Baldwin, H Scott; Paria, Bibhash C; Reese, Jeff
Persistent patency of the ductus arteriosus (PDA) is a common problem in preterm infants. The antacid cimetidine is a potent antagonist of the H2 histamine receptor but it also inhibits certain cytochrome P450 enzymes (CYPs), which may affect DA patency. We examined whether cimetidine contributes to PDA and is mediated by CYP inhibition rather than H2 blockade. Analysis of a clinical trial to prevent lung injury in premature infants revealed a significant association between cimetidine treatment and PDA. Cimetidine and ranitidine, both CYP inhibitors as well as H2 blockers, caused relaxation of the term and preterm mouse DA. CYP enzymes that are inhibited by cimetidine were expressed in DA subendothelial smooth muscle. The selective CYP3A inhibitor ketoconazole induced greater DA relaxation than cimetidine, whereas famotidine and other H2 antagonists with less CYP inhibitory effects caused less dilation. Histamine receptors were developmentally regulated and localized in DA smooth muscle. However, cimetidine caused DA relaxation in histamine-deficient mice, consistent with CYP inhibition, not H2 antagonism, as the mechanism for PDA. Oxygen-induced DA constriction was inhibited by both cimetidine and famotidine. These studies show that antacids and other compounds with CYP inhibitory properties pose a significant and previously unrecognized risk for PDA in critically ill newborn infants.
Tashiro, T; Ono, K; Watanabe, T; Inoie, M; Arai, H; Kimura, S; Kurokawa, K
Histamine H2 receptor antagonism by T-593 was investigated in Hepa cells expressing canine histamine H2 receptors. T-593 inhibited generation of cAMP in Hepa cells stimulated by 10(-5) mol/l histamine with an IC50 value of 2.3 x 10(-6) mol/l, (S)-(-)-T-593, one of the enantiomers comprising racemic T-593, inhibited cAMP generation with an IC50 value of 6.1 x 10(-7) mol/l. On the other hand, the other enantiomer (R)-(+)-T-593 exhibited only a negligible effect. Incubation of the cell with (S)-(-)-T-593 for 60 min depressed the maximal response of the concentration-response curve of histamine with a nonparallel rightward shift. The slope of a Schild plot was 1.27. In contrast, (S)-(-)-T-593 caused a parallel rightward shift of the curve, with a Schild plot slope that did not significantly differ from unity, by treating the cells for 15 min. The H2 receptor-blocking action of (S)-(-)-T-593 remained almost unaffected after washing out the drug, whereas the effect of ranitidine was reversible after washing. These results suggest that T-593 possesses a time-dependent insurmountable antagonistic action against histamine H2 receptor. T-593 may interact with the histamine H2 receptor molecule in a slowly associable and dissociable manner.
Gorska, Magdalena; Wyszkowska, Roksana Maja; Kuban-Jankowska, Alicja; Wozniak, Michal
Osteosarcoma is one of the most malignant bone tumors of childhood and adolescence. Interestingly, the presence of estrogen receptors α and β has been reported in human bone cells, including osteosarcoma. Thus, inhibitors of estrogens such as fulvestrant, are considered candidates for novel endocrine therapy in treatment of osteosarcoma. Another anticancer agent that seems to be very effective in treatment of osteosarcoma is a derivative of 17β-estradiol, 2-methoxyestradiol. The aim of this study was to determine the anticancer activities of pure anti-estrogen, fulvestrant and combined treatment of fulvestrant and 2-methoxyestradiol towards highly metastatic osteosarcoma 143B cells. 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay was used in order to determine the antiproliferative potential of the compounds, and western blotting for estrogen receptors α and β. Flow cytometry was used in order to determine induction of cell death, cell-cycle arrest, mitochondrial depolarization, and DNA damage. Herein, we showed that fulvestrant has anticancer activity only at high concentrations. We were able to find and expression of estrogen receptor β, while we did not detect estrogen receptor α in osteosarcoma 143B cells. Moreover, fulvestrant down-regulated the expression of estrogen receptor β, and this effect was reversed by 2-methoxyestradiol. Thus, the obtained data suggest that 2-methoxyestradiol may exert part of its anticancer activity through modulation of expression of estrogen receptor β.
Wang, Xiaoyong; Bi, Zhigang; Chu, Wenming; Wan, Yinsheng
Solar UV light comprises UVB wavelengths (290-320 nm) and UVA wavelengths (320-400 nm). UVB radiation reaches the epidermis and, to a lesser extent, the upper part of the dermis, while UVA radiation penetrates more deeply into human skin. Existing studies have demonstrated that UV-irradiated epidermal keratinocytes release cytokines that indirectly promote MMP-1 production in dermal fibroblasts. In this study, we first investigated the effect of IL-1 on MAPK activity, c-Jun and c-Fos mRNA expression, and MMP-1 and MMP-2 production in UVA-irradiated human dermal fibroblasts. The results showed that UVA irradiation dose-dependently increased MMP-1 but not MMP-2 production in human skin fibroblasts. IL-1alpha and IL-1beta promoted MMP-1 but not MMP-2 production in UVA-irradiated fibroblasts. Both IL-1alpha and IL-1beta activated MAP kinase, significantly elevating c-Jun and c-Fos mRNA expression. We then investigated the indirect effect of UVB-irradiated keratinocyte culture medium on MMP-1 production in UVA-irradiated primary cultured human dermal fibroblasts and the effect of IL-1Ra. The results showed that cell culture medium from UVB-irradiated keratinocytes increased MMP-1 production in UVA-irradiated fibroblasts, and IL-1Ra dose-dependently inhibited MMP-1 production. IL-1Ra dose-dependently inhibited c-Jun mRNA expression of fibroblasts with no significant effect on c-Fos mRNA expression. These results demonstrate that UVB-irradiated keratinocytes promoted MMP-1 production in UVA-irradiated fibroblasts in a paracrine manner while IL-1Ra reduced MMP-1 production through inhibiting c-Jun mRNA expression. Collectively, our data suggest that IL-1 plays an important role in the dermal collagen degradation associated with UV-induced premature aging of the skin and IL-1Ra may be applied for the prevention and treatment of photoaging.
Prantner, Daniel; Darville, Toni; Sikes, James D; Andrews, Charles W; Brade, Helmut; Rank, Roger G; Nagarajan, Uma M
Recent findings have implicated interleukin-1beta (IL-1beta) as an important mediator of the inflammatory response in the female genital tract during chlamydial infection. But how IL-1beta is produced and its specific role in infection and pathology are unclear. Therefore, our goal was to determine the functional consequences and cellular sources of IL-1beta expression during a chlamydial genital infection. In the present study, IL-1beta(-/-) mice exhibited delayed chlamydial clearance and decreased frequency of hydrosalpinx compared to wild-type (WT) mice, implying an important role for IL-1beta both in the clearance of infection and in the mediation of oviduct pathology. At the peak of IL-1beta secretion in WT mice, the major producers of IL-1beta in vivo are F4/80(+) macrophages and GR-1(+) neutrophils, but not CD45(-) epithelial cells. Although elicited mouse macrophages infected with Chlamydia muridarum in vitro secrete minimal IL-1beta, in vitro prestimulation of macrophages by Toll-like receptor (TLR) ligands such as lipopolysaccharide (LPS) purified from Escherichia coli or C. trachomatis L2 prior to infection greatly enhanced secretion of IL-1beta from these cells. By using LPS-primed macrophages as a model system, it was determined that IL-1beta secretion was dependent on caspase-1, potassium efflux, and the activity of serine proteases. Significantly, chlamydia-induced IL-1beta secretion in macrophages required bacterial viability but not growth. Our findings demonstrate that IL-1beta secreted by macrophages and neutrophils has important effects in vivo during chlamydial infection. Additionally, prestimulation of macrophages by chlamydial TLR ligands may account for the elevated levels of pro-IL-1beta mRNA observed in vivo in this cell type.
Leuenberger, Mathieu; Berner, Jeanne; Di Lucca, Julie; Fischer, Lara; Kaparos, Nikolaos; Conrad, Curdin; Hohl, Daniel; So, Alexander; Gilliet, Michel
PASS syndrome is a rare inflammatory disease characterized by a chronic-relapsing course of pyoderma gangrenosum, acne vulgaris, hidradenitis suppurativa and ankylosing spondylitis. Here, we describe a case of a patient with spontaneously recurrent purulent skin lesions along with seronegative spondylarthritis consistent with the PASS syndrome. During his disease exacerbation, the patient displayed episodes of fever along with elevated serum levels of interleukin (IL)-1β. Skin lesions were characterized by sterile neutrophilic infiltrates and showed a rapid response to the IL-1 receptor antagonist anakinra (Kineret®) consistent with the autoinflammatory nature of this disease. However, unlike other autoinflammatory diseases such as PAPA and PAPASH, we did not find mutations in the gene PSTPIP1, raising the possibility that other specific mutations in the IL-1 pathway may be involved.
Hassan, Ahmed M.; Jain, Piyush; Mayerhofer, Raphaela; Fröhlich, Esther E.; Farzi, Aitak; Reichmann, Florian; Herzog, Herbert; Holzer, Peter
Altered levels of colonic peptide YY (PYY) have been reported in patients suffering from functional and inflammatory bowel disorders. While the involvement of neuropeptide Y (NPY) and Y receptors in the regulation of nociception is well established, the physiological role of PYY in somatic and visceral pain is poorly understood. In this work,