Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.086
Filtrar
1.
MAbs ; 14(1): 2029675, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35133941

RESUMO

The functional interleukin 6 (IL-6) signaling complex is a hexameric structure composed of IL-6, IL-6Rα, and the signaling receptor gp130. There are three different modes of IL-6 signaling, classic signaling, trans-signaling, and trans-presentation, which are not functionally redundant and mediate pleiotropic effects on both physiological and pathophysiological states. Monoclonal antibodies against IL-6 or IL-6Rα have been successfully developed for clinical application. However, designing therapeutic interventions that block specific modes of IL-6 signaling in a pathologically relevant manner remains a great challenge. Here, we constructed a fusion protein Hyper-IL-6 (HyIL-6) composed of human IL-6 and IL-6Rα to develop specific blocking antibodies against the IL-6/IL-6Rα complex. We successfully screened the monoclonal antibody C14mab, which can bind to HyIL-6 with the binding constant 2.86 × 10-10 and significantly inhibit IL-6/IL-6Rα/gp130 complex formation. In vitro, C14mab effectively inhibited HyIL-6-stimulated signal transducer and activator of transcription 3 (STAT3) activation and related vascular endothelial growth factor (VEGF) induction. Moreover, C14mab efficaciously suppressed HyIL-6-induced acute phase response in vivo. Our data from hydrogen-deuterium exchange mass spectrometry demonstrate that C14mab mainly binds to site IIIa of IL-6 and blocks the final step in the interaction between gp130 and IL-6/IL-6Rα complex. Additionally, data from enzyme-linked immunosorbent assays and kinetics assays indicate that C14mab interacts simultaneously with IL-6 and IL-6Rα, while it does not interact with IL-6Rα alone. The unique features of C14mab may offer a novel alternative for IL-6 blockade and illuminate a better therapeutic intervention targeting IL-6.


Assuntos
Interleucina-6 , Receptores de Interleucina-6 , Anticorpos Monoclonais , Receptor gp130 de Citocina/química , Receptor gp130 de Citocina/metabolismo , Epitopos , Humanos , Interleucina-6/metabolismo , Receptores de Interleucina-6/química , Receptores de Interleucina-6/metabolismo , Fator A de Crescimento do Endotélio Vascular
2.
Physiol Rep ; 10(18): e15468, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36117389

RESUMO

Meprin metalloproteinases have been implicated in the pathophysiology of ischemia/reperfusion (IR)-induced kidney injury. Previous in vitro data showed that meprin ß proteolytically processes interleukin-6 (IL-6) resulting in its inactivation. Recently, meprin-ß was also shown to cleave the IL-6 receptor. The goal of this study was to determine how meprin ß expression impacts IL-6 and downstream modulators of the JAK2-STAT3-mediated signaling pathway in IR-induced kidney injury. IR was induced in 12-week-old male wild-type (WT) and meprin ß knockout (ßKO) mice and kidneys obtained at 24 h post-IR. Real-time PCR, western blot, and immunostaining/microscopy approaches were used to quantify mRNA and protein levels respectively, and immunofluorescence counterstaining with proximal tubule (PT) markers to determine protein localization. The mRNA levels for IL-6, CASP3 and BCL-2 increased significantly in both genotypes. Interestingly, western blot data showed increases in protein levels for IL-6, CASP3, and BCL-2 in the ßKO but not in WT kidneys. However, immunohistochemical data showed increases in IL-6, CASP3, and BCL-2 proteins in select kidney tubules in both genotypes, shown to be PTs by immunofluorescence counterstaining. IR-induced increases in p-STAT-3 and p-JAK-2 in ßKO at a global level but immunoflourescence counterstaining demonstrated p-JAK2 and p-STAT3 increases in select PT for both genotypes. BCL-2 increased only in the renal corpuscle of WT kidneys, suggesting a role for meprins expressed in leukocytes. Immunohistochemical analysis confirmed higher levels of leukocyte infiltration in WT kidneys when compared to ßKO kidneys. The present data demonstrate that meprin ß modulates IR-induced kidney injury in part via IL-6/JAK2/STAT3-mediated signaling.


Assuntos
Interleucina-6 , Traumatismo por Reperfusão , Animais , Caspase 3/metabolismo , Interleucina-6/metabolismo , Isquemia/metabolismo , Rim/metabolismo , Masculino , Metaloendopeptidases , Metaloproteases/metabolismo , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , Receptores de Interleucina-6/metabolismo , Reperfusão , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais
3.
Cytokine ; 159: 156020, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36057230

RESUMO

BACKGROUND: COVID-19 disease severity and need for intensive care has been associated with profound immune disturbances in which interleukin 6 (IL-6) is central. IL-6 signals through two pathways: classical IL-6 signalling with C-reactive protein (CRP) as a product is pivotal in the acute immune response against pathogens while IL-6 trans-signalling is involved in prolonged inflammation. We measured biomarkers of the IL-6 classical and trans-signalling pathways in patients with moderate or severe COVID-19 in the first wave of the COVID-19 pandemic. METHOD: In a longitudinal cohort study including patients admitted to Danderyd hospital, Stockholm, Sweden, with COVID-19 (n = 112), plasma IL-6 mirroring activity in both pathways, CRP as marker of classical signalling and the soluble IL-6 receptor (sIL-6R) and soluble glycoprotein 130 (sgp130) as markers of trans-signalling were analysed at baseline. Potential differences in biomarker levels between groups of moderate and severe COVID-19 defined by care level, level of respiratory support and one-month mortality was analysed, as was correlations between biomarkers. In addition, levels 4 months after hospital admission were compared to those at baseline. RESULTS: Levels of IL-6 and CRP were increased in severe COVID-19 whereas IL-6 trans-signalling markers (sIL-6R, sgp130) did not differ between the groups. CRP correlated positively with IL-6 in all patients while correlation with IL-6 could not be demonstrated for sIL-6R and sgp130 in either group. Levels of IL-6, CRP and sIL-6R were significantly decreased after 4 months whereas sgp130 levels increased. CONCLUSION: Classical signalling is the dominating IL-6 pathway in moderate-severe COVID-19.


Assuntos
COVID-19 , Interleucina-6 , Biomarcadores , Proteína C-Reativa , Receptor gp130 de Citocina/metabolismo , Humanos , Hiperplasia , Estudos Longitudinais , Pandemias , Receptores de Interleucina-6/metabolismo , SARS-CoV-2 , Suécia/epidemiologia
4.
Sci Rep ; 12(1): 12326, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853948

RESUMO

Activation of the kynurenine pathway (KP) has been reported in patients with pulmonary arterial hypertension (PAH) undergoing PAH therapy. We aimed to determine KP-metabolism in treatment-naïve PAH patients, investigate its prognostic values, evaluate the effect of PAH therapy on KP-metabolites and identify cytokines responsible for altered KP-metabolism. KP-metabolite levels were determined in plasma from PAH patients (median follow-up 42 months) and in rats with monocrotaline- and Sugen/hypoxia-induced PH. Blood sampling of PAH patients was performed at the time of diagnosis, six months and one year after PAH therapy. KP activation with lower tryptophan, higher kynurenine (Kyn), 3-hydroxykynurenine (3-HK), quinolinic acid (QA), kynurenic acid (KA), and anthranilic acid was observed in treatment-naïve PAH patients compared with controls. A similar KP-metabolite profile was observed in monocrotaline, but not Sugen/hypoxia-induced PAH. Human lung primary cells (microvascular endothelial cells, pulmonary artery smooth muscle cells, and fibroblasts) were exposed to different cytokines in vitro. Following exposure to interleukin-6 (IL-6)/IL-6 receptor α (IL-6Rα) complex, all cell types exhibit a similar KP-metabolite profile as observed in PAH patients. PAH therapy partially normalized this profile in survivors after one year. Increased KP-metabolites correlated with higher pulmonary vascular resistance, shorter six-minute walking distance, and worse functional class. High levels of Kyn, 3-HK, QA, and KA measured at the latest time-point were associated with worse long-term survival. KP-metabolism was activated in treatment-naïve PAH patients, likely mediated through IL-6/IL-6Rα signaling. KP-metabolites predict response to PAH therapy and survival of PAH patients.


Assuntos
Interleucina-6 , Cinurenina , Hipertensão Arterial Pulmonar , Receptores de Interleucina-6 , Animais , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Humanos , Hipóxia/metabolismo , Interleucina-6/metabolismo , Ácido Cinurênico/metabolismo , Cinurenina/metabolismo , Monocrotalina , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/patologia , Ácido Quinolínico/metabolismo , Ratos , Receptores de Interleucina-6/metabolismo
5.
Nature ; 607(7918): 366-373, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35705809

RESUMO

Chromosomal instability (CIN) drives cancer cell evolution, metastasis and therapy resistance, and is associated with poor prognosis1. CIN leads to micronuclei that release DNA into the cytoplasm after rupture, which triggers activation of inflammatory signalling mediated by cGAS and STING2,3. These two proteins are considered to be tumour suppressors as they promote apoptosis and immunosurveillance. However, cGAS and STING are rarely inactivated in cancer4, and, although they have been implicated in metastasis5, it is not known why loss-of-function mutations do not arise in primary tumours4. Here we show that inactivation of cGAS-STING signalling selectively impairs the survival of triple-negative breast cancer cells that display CIN. CIN triggers IL-6-STAT3-mediated signalling, which depends on the cGAS-STING pathway and the non-canonical NF-κB pathway. Blockade of IL-6 signalling by tocilizumab, a clinically used drug that targets the IL-6 receptor (IL-6R), selectively impairs the growth of cultured triple-negative breast cancer cells that exhibit CIN. Moreover, outgrowth of chromosomally instable tumours is significantly delayed compared with tumours that do not display CIN. Notably, this targetable vulnerability is conserved across cancer types that express high levels of IL-6 and/or IL-6R in vitro and in vivo. Together, our work demonstrates pro-tumorigenic traits of cGAS-STING signalling and explains why the cGAS-STING pathway is rarely inactivated in primary tumours. Repurposing tocilizumab could be a strategy to treat cancers with CIN that overexpress IL-6R.


Assuntos
Instabilidade Cromossômica , Interleucina-6 , Proteínas de Membrana , Nucleotidiltransferases , Neoplasias de Mama Triplo Negativas , Anticorpos Monoclonais Humanizados/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Instabilidade Cromossômica/genética , Reposicionamento de Medicamentos , Humanos , Interleucina-6/antagonistas & inibidores , Interleucina-6/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , NF-kappa B/metabolismo , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Receptores de Interleucina-6/antagonistas & inibidores , Receptores de Interleucina-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
6.
Front Immunol ; 13: 860703, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35493452

RESUMO

Background: Genetic studies have linked polymorphisms in the interleukin 6 receptor (IL6R) gene to the risk of multiple human diseases and phenotypes, yet have reported inconsistent results. We aimed to synthesize current knowledge of variants in the IL6R gene on the risk of diseases and phenotypes. Methods: We searched the Medline and Embase databases to identify relevant publications. Meta-analysis was performed utilizing DerSimonian and Laird random-effects model. We also graded cumulative evidence for significant associations. Furthermore, phenome-wide analyses and functional annotations were performed for variants with strong evidence. Results: We included 155 studies for evaluating the associations between 80 polymorphisms in the IL6R gene and the risk of 102 human diseases and 98 phenotypes. We conducted 58 main meta-analyses, and 41 significant associations were identified. Strong evidence was assigned to 29 associations that investigated ten variants (rs2228145, rs4129267, rs7529229, rs4537545, rs7518199, rs4845625, rs4553185, rs4845618, rs4845371, and rs6667434) related to the risk of four cardiovascular diseases (coronary heart disease, coronary artery disease, atherosclerosis, and abdominal aortic aneurysms), four inflammatory diseases (rheumatoid arthritis, Crohn's disease, dermatitis, and asthma), and concentration of four phenotypes (C-reactive protein, fibrinogen, IL-6, and sIL-6R). Furthermore, phenome-wide analysis verified that rs2228145 associated with asthma and dermatitis risk. Functional analyses indicated that these polymorphisms fall within exon, enhancer regions. Conclusions: Our study comprehensively summarizes current data on the genetic architecture of the IL6R gene and highlights the pharmacological targeting potential of IL-6R on cardiovascular and inflammatory diseases.


Assuntos
Asma , Doença da Artéria Coronariana , Dermatite , Asma/genética , Genótipo , Humanos , Fenótipo , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina-6/genética , Receptores de Interleucina-6/metabolismo
7.
Front Immunol ; 13: 891456, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634332

RESUMO

IL-6 is one of the major mediators of the hyper-inflammatory responses with complex biological functions as it can signal via different modes of action. IL-6 by classical signalling has anti-inflammatory and antibacterial activities, while trans-signalling mediates pro-inflammatory effects. The net biological effect of IL-6 is established by multiple factors beyond its absolute concentration. Here, we assess the relationship between IL-6 signalling variables [IL-6, soluble IL-6R (sIL-6R) and soluble gp130 (sgp130)] and outcomes in a cohort of 366 COVID-19 patients. The potential trans-signalling was evaluated by a ratio between the pro-inflammatory binary IL-6:sIL-6R complex and the inactive ternary IL-6:sIL-6R:sgp130 complex (binary/ternary complex) and the fold molar excess of sgp130 over sIL-6R (FME). Our data provide new evidence that high levels of IL-6, sIL-6R, sgp130, binary/ternary complex ratio, and low FME are independent predictors of COVID-19 severity in survivor patients (without death), and the combination of IL-6 + sIL-6R + sgp130 exhibited the most robust classification capacity. Conversely, in a subgroup of patients with a very poor prognosis, we found that high levels of IL-6 and low levels of sIL-6R, sgp130, and binary/ternary complex ratio were predictors of death. In this context, the highest predictive capacity corresponded to the combined analysis of IL-6 + FME + lymphopenia + creatinine. Herein, we present IL-6 signalling variables as a helpful tool for the early identification and stratification of patients with clear implications for treatment and clinical decision-making.


Assuntos
COVID-19 , Interleucina-6 , Receptores de Interleucina-6 , Transdução de Sinais , COVID-19/diagnóstico , COVID-19/imunologia , Receptor gp130 de Citocina/metabolismo , Humanos , Interleucina-6/metabolismo , Receptores de Interleucina-6/metabolismo , Índice de Gravidade de Doença
8.
Cells ; 11(10)2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35626741

RESUMO

Annexin A1 (AnxA1) is a pleiotropic protein that exerts essential roles in breast cancer (BC) growth and aggressiveness. In our previous work, we described the autocrine signaling of AnxA1 through formyl peptide receptor 1 (FPR1) in the triple-negative (TN) BC cell line, MDA-MB-231. Here, we aimed to describe the interaction between the AnxA1/FPR1 and the Interleukin-6 (IL-6) signaling pathways and their role in the tumor microenvironment (TME). First, we demonstrated that AnxA1 and IL-6 expression levels are correlated in BC tissue samples. In three TNBC cell lines, overexpression of both AnxA1 and IL-6 was also identified. Next, we inhibited FPR1, the IL-6 receptor and STAT3 in both MDA-MB-231 and MDA-MB-157 cells. The FPR1 inhibition led to increased levels of IL-6 and secreted AnxA1 in both cell lines. On the other side, inhibition of the IL-6 receptor or STAT3 led to the impairment of AnxA1 secretion, suggesting the essential role of the IL-6 signaling cascade in the activation of the AnxA1/FPR1 autocrine axis. Finally, we described the interaction between IL-6 and the AnxA1/FPR1 pathways and their role on the TME by analyzing the effect of supernatants derived from MDA-MB-231 and MDA-MB-157 cells under the inhibition of FPR1 or IL-6 signaling on fibroblast cell motility.


Assuntos
Anexina A1 , Neoplasias de Mama Triplo Negativas , Anexina A1/metabolismo , Humanos , Interleucina-6/metabolismo , Receptores de Formil Peptídeo/metabolismo , Receptores de Interleucina-6/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Microambiente Tumoral
9.
Hum Reprod ; 37(7): 1489-1504, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35551394

RESUMO

STUDY QUESTION: Is activation of signal transducer and activator of transcription 3 (STAT3) via interleukin-6 (IL-6) trans-signaling involved in fibrosis of endometriosis? SUMMARY ANSWER: Persistent activation of STAT3 via IL-6 trans-signaling is involved in fibrosis of endometriosis. WHAT IS KNOWN ALREADY: Our previous study showed that sustained low-grade inflammation promotes a fibrotic phenotype in endometriotic stromal cells. However, the underlying mechanisms of the establishment of non-resolving, low-grade inflammation in endometriosis remain to be clarified. STUDY DESIGN, SIZE, DURATION: Endometrial and/or endometriotic samples of 60 patients who had histological evidence of deep endometriosis and endometrial samples from 32 healthy fertile women were analyzed. PARTICIPANTS/MATERIALS, SETTING, METHODS: The effects of priming with ligands of Toll-like receptors (TLRs) 2, 3 and 4 on secretion of inflammatory mediators (tumor necrosis factor-α, C-X-C motif chemokine ligand-10 [CXCL-10], IL6 and IL-10) after a second challenge with TLR ligands in endometrial and endometriotic stromal cells were investigated. Then, the effects of IL-6/soluble (s) IL-6 receptor (R)/STAT3 signaling, as well as inhibition of STAT3 activation by knockdown of STAT3 or pharmacological inhibition (S3I-201), on the pro-fibrotic phenotype in endometrial and endometriotic stromal cells in vitro were investigated. MAIN RESULTS AND THE ROLE OF CHANCE: Priming with TLR ligands for 4 h had no significant effects, whereas 24 h of priming significantly decreased secretion of IL-6, after a second challenge in endometrial stromal cells of healthy women. In endometriotic stromal cells, whereas 24 h of priming had no significant effects, priming with TLR ligands for 4 h significantly increased secretion of IL-6 after a second challenge. IL-6/soluble IL-6 receptor (sIL-6R) induced a pro-fibrotic phenotype (cell proliferation, collagen type I synthesis, α-smooth muscle actin positive stress fibers, cell migration and collagen gel contraction) as well as nuclear factor-kappa B (NF-κB) activation of endometriotic stromal cells. In contrast, IL-6/sIL-6R had no significant effects on either a pro-fibrotic phenotype or NF-κB activation of endometrial stromal cells of healthy women. Stimulation with transforming growth factor (TGF)-ß1 and/or IL-6/sIL-6R for 1 h and 48 h activated STAT3, but induced very low or no suppressor of cytokine signaling (SOCS) 1 and 3 protein expression in endometriotic stromal cells. In endometrial stromal cells of healthy women, IL-6/sIL-6R-induced STAT3 and SOCS1/3 expression at 1 h, whereas no STAT3 activation was detected at 48 h. Knockdown of STAT3 gene or S3I-201 (a STAT3 inhibitor) decreased the IL-6/sIL-6R-induced pro-fibrotic phenotype as well as NF-κB activation and TGF-ß1-induced cell proliferation of endometriotic stromal cells. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: In vivo studies are required to confirm the present in vitro results. However, it remains challenging to mimic non-resolving chronic inflammation in animal models, as active inflammation can resolve spontaneously. WIDER IMPLICATIONS OF THE FINDINGS: Dysfunction of negative regulators of IL-6/sIL-6R/STAT3 signaling may cause persistent activation of STAT3 in endometriosis. Since STAT3 activation in the endometrium is essential for successful embryo implantation, treatment with STAT3 inhibitors would not be appropriate for women wishing to conceive. However, targeting impaired negative regulation of IL-6/sIL-6R/STAT3 signaling may still represent a promising avenue for the treatment of endometriosis. STUDY FUNDING/COMPETING INTEREST(S): This study was supported in part by the KARL STORZ SE & Co. KG (Tuttlingen, Germany). There are no conflicts of interest.


Assuntos
Endometriose , Animais , Endometriose/patologia , Endométrio/metabolismo , Feminino , Fibrose , Humanos , Inflamação/metabolismo , Interleucina-6/metabolismo , NF-kappa B , Receptores de Interleucina-6/metabolismo , Receptores de Interleucina-6/uso terapêutico , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/uso terapêutico , Células Estromais/metabolismo
10.
PLoS One ; 17(4): e0266632, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35385549

RESUMO

Interleukin 6 (IL-6) is a cytokine with various biological functions in immune regulation, hematopoiesis, and inflammation. Elevated IL-6 levels have been identified in several severe disorders such as sepsis, acute respiratory distress syndrome (ARDS), and most recently, COVID-19. The biological activity of IL-6 relies on interactions with its specific receptor, IL-6Rα, including the membrane-bound IL-6 receptor (mIL-6R) and the soluble IL-6 receptor (sIL-6R). Thus, inhibition of the interaction between these two proteins would be a potential treatment for IL-6 related diseases. To date, no orally available small-molecule drug has been approved. This study focuses on finding potential small molecules that can inhibit protein-protein interactions between IL-6 and its receptor IL-6Rα using its crystal structure (PDB ID: 5FUC). First, two pharmacophore models were constructed based on the interactions between key residues of IL-6 (Phe74, Phe78, Leu178, Arg179, Arg182) and IL-6Rα (Phe229, Tyr230, Glu277, Glu278, Phe279). A database of approximately 22 million compounds was screened using 3D-pharmacophore models, molecular docking models, and ADMET properties. By analyzing the interactive capability of successfully docked compounds with important amino acids, 12 potential ligands were selected for further analysis via molecular dynamics simulations. Based on the stability of the complexes, the high interactions rate of each ligand with the key residues of IL-6/IL-6Rα, and the low binding free energy calculation, two compounds ZINC83804241 and ZINC02997430, were identified as the most potential IL-6 inhibitor candidates. These results will pave the way for the design and optimization of more specific compounds to combat cytokine storm in severe coronavirus patients.


Assuntos
Interleucina-6 , Simulação de Dinâmica Molecular , Humanos , Interleucina-6/antagonistas & inibidores , Ligantes , Simulação de Acoplamento Molecular , Receptores de Interleucina-6/metabolismo
11.
J Clin Endocrinol Metab ; 107(7): 1854-1864, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35442403

RESUMO

CONTEXT: Interleukin-6 (IL-6) is implicated in skeletal muscle wasting and in regulating skeletal muscle hypertrophy in the healthy state. OBJECTIVE: This work aimed to determine the role of IL-6 in regulating systemic protein and amino acid metabolism during rest, exercise, and recovery in lean and obese humans. METHODS: In a nonrandomized, single-blind design, 12 lean and 9 obese individuals were infused first with 0.9% saline (Saline), secondly with the IL-6 receptor antibody tocilizumab (Acute IL-6R ab), and 21 days later with saline while still under tocilizumab influence (Chronic IL-6R ab). Outcome measures were determined before, during, and after 90 minutes of exercise at 40% Wattmax by isotope dilution technique, using primed continuous infusion of L-[ring-D5]phenylalanine and L-[D2]tyrosine. Main outcomes measures included systemic protein turnover and plasma amino acid concentrations. RESULTS: We saw no effect of acute or chronic IL-6 receptor blockade on protein turnover. In lean individuals, chronic IL-6 receptor blockade increased plasma concentrations of total amino acids (rest Δ + 186 µmol/L; 95% CI, 40-332; recovery Δ + 201 µmol/L; 95% CI, 55-347) and essential amino acids (rest Δ + 43 µmol/L; 95% CI, 12-76; recovery Δ + 45 µmol/L; 95% CI, 13-77) independently of exercise but had no such effect in obese individuals (total amino acids rest Δ + 63 µmol/L; 95% CI, -170 to 295, recovery Δ - 23 µmol/L, 95% CI, -256 to 210; essential amino acids rest Δ + 26 µmol/L; 95% CI, -21 to 73, recovery Δ + 11 µmol/L; 95% CI, -36 to 58). CONCLUSION: IL-6 receptor blockade has no effect on protein turnover in fasting lean and obese humans during rest, exercise, and recovery. Chronic IL-6 receptor blockade increases total and essential amino acid concentrations only in lean individuals.


Assuntos
Interleucina-6 , Obesidade , Aminoácidos/metabolismo , Humanos , Interleucina-6/metabolismo , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Fenilalanina , Receptores de Interleucina-6/metabolismo , Método Simples-Cego
12.
Mol Metab ; 61: 101488, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35470093

RESUMO

OBJECTIVE: IL-6 is an important contributor to glucose and energy homeostasis through changes in whole-body glucose disposal, insulin sensitivity, food intake and energy expenditure. However, the relative contributions of peripheral versus central IL-6 signaling to these metabolic actions are presently unclear. A conditional mouse model with reduced brain IL-6Ra expression was used to explore how blunted central IL-6 signaling alters metabolic status in lean and obese mice. METHODS: Transgenic mice with reduced levels of central IL-6 receptor alpha (IL-6Ra) (IL-6Ra KD mice) and Nestin Cre controls (Cre+/- mice) were fed standard chow or high-fat diet for 20 weeks. Obese and lean mouse cohorts underwent metabolic phenotyping with various measures of energy and glucose homeostasis determined. Glucose-stimulated insulin secretion was assessed in vivo and ex vivo in both mouse groups. RESULTS: IL-6Ra KD mice exhibited altered body fat mass, liver steatosis, plasma insulin, IL-6 and NEFA levels versus Cre+/- mice in a diet-dependent manner. IL-6Ra KD mice had increased food intake, higher RER, decreased energy expenditure with diminished cold tolerance compared to Cre+/- controls. Standard chow-fed IL-6Ra KD mice displayed reduced plasma insulin and glucose-stimulated insulin secretion with impaired glucose disposal and unchanged insulin sensitivity. Isolated pancreatic islets from standard chow-fed IL-6Ra KD mice showed comparable morphology and glucose-stimulated insulin secretion to Cre+/- controls. The diminished in vivo insulin secretion exhibited by IL-6Ra KD mice was recovered by blockade of autonomic ganglia. CONCLUSIONS: This study shows that central IL-6Ra signaling contributes to glucose and energy control mechanisms by regulating food intake, energy expenditure, fuel flexibility and insulin secretion. A plausible mechanism linking central IL-6Ra signaling and pancreatic insulin secretion is through the modulation of autonomic output activity. Thus, brain IL-6 signaling may contribute to the central adaptive mechanisms engaged in response to metabolic stress.


Assuntos
Glucose , Resistência à Insulina , Receptores de Interleucina-6 , Animais , Glucose/metabolismo , Insulina/metabolismo , Secreção de Insulina/fisiologia , Interleucina-6/metabolismo , Camundongos , Receptores de Interleucina-6/deficiência , Receptores de Interleucina-6/metabolismo
13.
Int J Mol Sci ; 23(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35163371

RESUMO

Vascular endothelial cells express glycoprotein 130 (gp130), which is utilized as a signaling receptor by cytokines in the interleukin-6 (IL-6) family. Several IL-6 family cytokines can be found in the circulatory system during physiological or pathological conditions, and may influence endothelial function and response. This study evaluated and compared the cellular and molecular responses induced by IL-6 family cytokines in human endothelial cells. A proteomic analysis showed that IL-6 family cytokines induce the release of a range of proteins from endothelial cells, such as C-C motif chemokine ligand 23, hepatocyte growth factor, and IL-6. Pathway analysis indicated that gp130-signaling in endothelial cells regulates several functions related to angiogenesis and immune cell recruitment. The present investigation also disclosed differences and similarities between different IL-6 family cytokines in their ability to induce protein release and regulate gene expression and intracellular signaling, in regards to which oncostatin M showed the most pronounced effect. Further, this study showed that soluble gp130 preferentially blocks trans-signaling-induced responses, but does not affect responses induced by classic signaling. In conclusion, IL-6 family cytokines induce both specific and overlapping molecular responses in endothelial cells, and regulate genes and proteins involved in angiogenesis and immune cell recruitment.


Assuntos
Citocinas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Interleucina-6/metabolismo , Receptor gp130 de Citocina/metabolismo , Regulação da Expressão Gênica , Humanos , Interleucina-6/genética , Sistema de Sinalização das MAP Quinases , Fosforilação , Receptores de Interleucina-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Transcrição Genética
14.
Pharmacol Res Perspect ; 10(2): e00940, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35212163

RESUMO

Anti-proinflammatory cytokine therapies against interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-1 are major advancements in treating inflammatory diseases, especially rheumatoid arthritis. Such therapies are mainly performed by injection of antibodies against cytokines or cytokine receptors. We initially found that the glycolytic inhibitor 2-deoxy-d-glucose (2-DG), a simple monosaccharide, attenuated cellular responses to IL-6 by inhibiting N-linked glycosylation of the IL-6 receptor gp130. Aglycoforms of gp130 did not bind to IL-6 or activate downstream intracellular signals that included Janus kinases. 2-DG completely inhibited dextran sodium sulfate-induced colitis, a mouse model for inflammatory bowel disease, and alleviated laminarin-induced arthritis in the SKG mouse, an experimental model for human rheumatoid arthritis. These diseases have been shown to be partially dependent on IL-6. We also found that 2-DG inhibited signals for other proinflammatory cytokines such as TNF-α, IL-1ß, and interferon -γ, and accordingly, prevented death by another inflammatory disease, lipopolysaccharide (LPS) shock. Furthermore, 2-DG prevented LPS shock, a model for a cytokine storm, and LPS-induced pulmonary inflammation, a model for acute respiratory distress syndrome of coronavirus disease 2019 (COVID-19). These results suggest that targeted therapies that inhibit cytokine receptor glycosylation are effective for treatment of various inflammatory diseases.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Desoxiglucose/farmacologia , Glicosilação/efeitos dos fármacos , Inflamação/prevenção & controle , Receptores de Citocinas/efeitos dos fármacos , Animais , Células Cultivadas , Receptor gp130 de Citocina/antagonistas & inibidores , Receptor gp130 de Citocina/metabolismo , Síndrome da Liberação de Citocina/prevenção & controle , Citocinas/metabolismo , Inflamação/induzido quimicamente , Janus Quinases/efeitos dos fármacos , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Citocinas/imunologia , Receptores de Citocinas/metabolismo , Receptores de Interleucina-6/antagonistas & inibidores , Receptores de Interleucina-6/genética , Receptores de Interleucina-6/metabolismo
15.
Int J Mol Sci ; 23(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35216135

RESUMO

Interleukin-6 (IL-6) is a multipotent cytokine. IL-6 plays a dual role in inflammation through both classical signaling (IL-6 binds membrane IL-6 receptor/IL-6R) and trans-signaling (IL-6 binds soluble IL-6R). However, the regulation of IL-6 activity, especially the regulation of signaling pathways and downstream genes mediated by IL-6 trans-signaling, remains largely unclear in teleost. Grass carp (Ctenopharyngodon idellus) hepatic (L8824) cells, kidney (CIK) cells, and primary hepatocytes were used as test models in this study. First, the biological activity of recombinant blunt snout bream (Megalobrama amblycephala) IL-6 (rmaIL-6) and sIL-6R (rmasIL-6R) was verified by quantitative PCR (qPCR) and western blot. The western blot results showed that rmaIL-6 significantly upregulated signal transducer and activator of transcription 3 (STAT3) phosphorylation in L8824 cells and primary hepatocytes, while rmaIL-6 in combination with rmasIL-6R (rmaIL-6+rmasIL-6R) significantly upregulated STAT3 phosphorylation in all types of cells. Furthermore, maIL-6 and maIL-6+rmasIL-6R could only induce extracellular-signal-regulated kinase 1/2 (ERK1/2) phosphorylation in L8824 cells and CIK cells, respectively. Therefore, IL-6 mainly acts by activating the janus kinase (JAK)/STAT3 pathway rather than the mitogen-activated protein kinase (MEK)/ERK pathway. Finally, the activation of the JAK2/STAT3 pathway was shown to be essential for the generation of socs3a and socs3b induced by IL-6 trans-signaling after treatment by JAK2/STAT3 pathway inhibitors (c188-9 and TG101348). These findings provide functional insights into IL-6 classical signaling and trans-signaling regulatory mechanisms in teleost, enriching our knowledge of fish immunology.


Assuntos
Carpas/metabolismo , Interleucina-6/metabolismo , Receptores de Interleucina-6/metabolismo , Transdução de Sinais/fisiologia , Animais , Linhagem Celular , Fibroblastos/metabolismo , Hepatócitos/metabolismo , Rim/metabolismo , Fígado/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Fosforilação/fisiologia
16.
Reprod Biol ; 22(1): 100607, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35085910

RESUMO

This study embarked on the assessment regarding the function and mechanism of miR-520h/IL6R axis in polycystic ovary syndrome (PCOS). Specifically, we analyzed the differential expression of IL6R in PCOS samples and normal samples based on the GEO database, and then verified IL6R expression in KGN cells (Human granulosa-like tumor cell line) using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) and western blot. MiRNA targeting IL6R was predicted by bioinformatics analysis and verified by luciferase reporter assay, qRT-PCR and western blot. KGN cells were transfected with miR-520h inhibitor and si-IL6R, and then the cell viability and apoptosis were detected by cell counting kit-8 (CCK-8) and flow cytometry assays. Additionally, western blot was applied to examine the expressions of cell cycle-, apoptosis-, and JAK / STAT pathway-related proteins. IL6R was highly expressed in PCOS and KGN cells, and IL6R silencing inhibited the viability, while promoting the apoptosis of KGN cells. Importantly, miR-520h directly targeted IL6R and inhibited IL6R expression. Moreover, downregulation of miR-520h enhanced the cell viability, impeded the cell apoptosis, upregulated the expressions of CDK2, CCNB1, Bcl-2, activated JAK/STAT pathway and downregulated Bax expression in KGN cells. Of note, knockdown of IL6R can reverse the biological functions of miR-520h in KGN cells. Collectively, miR-520h hindered the proliferation and promoted the apoptosis of KGN cells via targeting IL6R to inhibit the development of PCOS, and these effects were possibly realized by JAK/STAT pathway. However, the effect of miR-520h in the progression of PCOS need to further study in the GCs.


Assuntos
Apoptose , MicroRNAs , Síndrome do Ovário Policístico , Apoptose/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Feminino , Células da Granulosa/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Síndrome do Ovário Policístico/metabolismo , Receptores de Interleucina-6/genética , Receptores de Interleucina-6/metabolismo , Transdução de Sinais
17.
Nano Lett ; 22(2): 751-760, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35030010

RESUMO

In recent years, targeted therapies and immunotherapeutics, along with conventional chemo- and radiotherapy, have greatly improved cancer treatments. Unfortunately, in cancer patients, anemia, either as a complication of cancer progression or as the result of cancer treatment, undermines the expected therapeutic efficacy. Here, we developed a smart nanosystem based on the palladium nanoplates (PdPLs) to deliver tocilizumab (TCZ, a widely used IL-6R antibody) to the liver for specific blockade of IL-6/IL-6R signaling to correct anemia. With chemical modifications, this nanosystem delivered a large mass of TCZ and enhanced liver delivery, inducing a marked suppression of hepcidin expression as a result of diminished IL-6 signaling. Through this mechanism, significant suppression of tumor progression was realized (at least in part) because of the corrected anemia after treatment.


Assuntos
Anemia , Neoplasias , Anemia/tratamento farmacológico , Anemia/etiologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Paládio/farmacologia , Paládio/uso terapêutico , Receptores de Interleucina-6/antagonistas & inibidores , Receptores de Interleucina-6/genética , Receptores de Interleucina-6/metabolismo
18.
Shock ; 57(1): 24-30, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34172608

RESUMO

BACKGROUND: Severe trauma is associated with severe systemic inflammation and neuroendocrine activation that is associated with erythroid progenitor growth suppression and refractory anemia. Although distinct transcriptional profiles have been detected in numerous tissue types after trauma, no study has yet characterized this within the bone marrow. This study sought to identify a unique bone marrow transcriptomic response following trauma. METHODS: In a prospective observational cohort study, bone marrow was obtained from severely injured trauma patients with a hip or femur fracture (n = 52), elective hip replacement patients (n = 33), and healthy controls (n = 11). RNA was isolated from bone marrow using a Purelink RNA mini kit. Direct quantification of mRNA copies was performed by NanoString Technologies on a custom gene panel. RESULTS: Trauma patients displayed an upregulation of genes encoding receptors known to have inhibitory downstream effects on erythropoiesis, including ferroportin, interleukin-6 (IL-6) receptor, transforming growth factor-beta (TGF-ß) receptor, and IL-10, as well as genes involved in innate immunity including toll-like receptor 4 (TLR4)-mediated signaling factors. In contrast, hip replacement patients had downregulated transcription of IL-1ß, IL-6, TGF-ß, tumor necrosis factor alpha, and the HAMP gene with no change in TLR4-mediated signaling factors. CONCLUSIONS: A unique transcriptomic response within the bone marrow was identified following severe trauma compared to elective hip replacement. These transcriptomic differences were related to the innate immune response as well as known inhibitors of erythropoiesis. Although confined to just one time point, this differential transcriptional response may be linked to refractory anemia and inflammation after injury.


Assuntos
Medula Óssea/metabolismo , Fraturas do Fêmur , Fraturas do Quadril , RNA Mensageiro/metabolismo , Adulto , Artroplastia de Quadril , Estudos de Casos e Controles , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Regulação para Baixo , Hepcidinas/genética , Hepcidinas/metabolismo , Humanos , Interleucinas/genética , Interleucinas/metabolismo , Linfotoxina-alfa/genética , Linfotoxina-alfa/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Receptores de Interleucina-6/genética , Receptores de Interleucina-6/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
19.
FEBS Lett ; 596(5): 557-566, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34738234

RESUMO

Interleukin-6 (IL-6) is an inflammatory cytokine, the level of which is highly elevated in most, if not all, inflammatory states. IL-6 triggers cell type-specific responses and acts on target cells via a specific interleukin-6 receptor (IL-6R), which, together with IL-6, binds to and induces the dimerization of a second receptor subunit, gp130. IL-6 also binds to soluble IL-6R, and this complex interacts with gp130, regardless of IL-6R expression. This allows cells that do not express IL-6R and would be otherwise insensitive to IL-6 to respond to it. We have generated a constitutively active version of gp130 by forced leucine-zipper-mediated dimerization, named L-gp130. Once inserted into the Rosa26 locus of mice, L-gp130 can be activated in a cell-autonomous manner by crossing these mice with any Cre-recombinase transgenic mouse strain. Activation of gp130 in hepatocytes produced liver-specific effects such as the induction of acute-phase proteins, but it also had profound systemic effects on the immune system. Such local and systemic effects of interleukin-6 will be reviewed.


Assuntos
Interleucina-6 , Neoplasias , Animais , Receptor gp130 de Citocina/genética , Receptor gp130 de Citocina/metabolismo , Citocinas/metabolismo , Inflamação/metabolismo , Interleucina-6/metabolismo , Camundongos , Neoplasias/genética , Receptores de Interleucina-6/metabolismo
20.
Biochim Biophys Acta Mol Cell Res ; 1869(1): 119143, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34626681

RESUMO

The pleiotropic cytokine interleukin-6 (IL-6) is involved in numerous physiological and pathophysiological functions that include development, immune cell differentiation, inflammation and cancer. IL-6 can signal via the membrane-bound IL-6 receptor (IL-6R, classic signaling) or via soluble forms of the IL-6R (sIL-6R, trans-signaling). Both modes of signaling induce the formation of a homodimer of the signal transducing ß-receptor glycoprotein 130 (gp130) and the activation of several intracellular signaling cascades, e.g. the Jak/STAT pathway. Intriguingly, only IL-6 trans-signaling is required for the pro-inflammatory properties of IL-6, while regenerative and anti-inflammatory functions are mediated via classic signaling. The sIL-6R is generated by different molecular mechanisms, including alternative mRNA splicing, proteolysis of the membrane-bound IL-6R and the release of extracellular vesicles. In this review, we give an in-depth overview on these molecular mechanisms with a special emphasize on IL-6R cleavage by the metalloprotease ADAM17 and other proteases. We discuss the biological functions of the sIL-6R and highlight attempts to selectively block IL-6 trans-signaling in pre-clinical animal models as well as in clinical studies in patients with inflammatory bowel disease.


Assuntos
Doenças Inflamatórias Intestinais/tratamento farmacológico , Proteólise , Receptores de Interleucina-6/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Humanos , Interleucina-6/metabolismo , Receptores de Interleucina-6/genética , Proteínas Recombinantes de Fusão/farmacologia , Transdução de Sinais/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...