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1.
Arthritis Res Ther ; 24(1): 236, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36280849

RESUMO

BACKGROUND: Endothelial dysfunction contributes to increased cardiovascular (CV) disease in rheumatoid arthritis (RA). Angiogenic T cells (Tang) are a key regulator of vascular function via their interaction with endothelial progenitor cells (EPCs). Methotrexate (MTX) has been associated to reduced CV disease risk, but its effects on endothelial homeostasis have been poorly explored. We investigated MTX effects on endothelial homeostasis in early, treatment-naïve RA patients. METHODS: Fifteen untreated, early RA patients and matched healthy controls (HC) were enrolled. RA patients with long-standing disease in remission or low disease activity treated with MTX for at least 6 months were selected as controls. Circulating CD28+ and CD28null Tang cell, endothelial microparticle (EMP), EPC and soluble vascular cell adhesion molecule (sVCAM)-1 levels were measured. RESULTS: Tang percentage was higher in early RA than in HCs and significantly increased after 3-month MTX treatment. Tang cells in RA were characterized by higher percentage of CD28null and lower CD28-positive cells than HCs. MTX restored a Tang cell phenotype similar to HCs. Altered sVCAM-1, EMP and EPC were restored to levels similar to HCs after a 3-month MTX. Biomarker levels after 3 months of MTX were not different to those of patients with long-standing treatment. CONCLUSIONS: MTX has a positive effect on Tang, sVCAM-1, EPCs and EMPs in RA. Restoration of imbalance between CD28 + and CD28null Tang by MTX may be one of the mechanisms underlying its favourable effects on endothelial dysfunction. These effects seem to be long-lasting and independent from systemic inflammation reduction, suggesting a direct effect of MTX on the endothelium.


Assuntos
Antirreumáticos , Artrite Reumatoide , Humanos , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Biomarcadores , Antígenos CD28 , Endotélio , Metotrexato/uso terapêutico , Molécula 1 de Adesão de Célula Vascular
4.
Diabetes ; 69(5): 965-980, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32169893

RESUMO

As an alternative to lifelong insulin supplementation, potentiation of immune tolerance in patients with type 1 diabetes could prevent the autoimmune destruction of pancreatic islet ß-cells. This study was aimed to assess whether the G3c monoclonal antibody (mAb), which triggers the glucocorticoid-induced TNFR-related (Gitr) costimulatory receptor, promotes the expansion of regulatory T cells (Tregs) in SV129 (wild-type) and diabetic-prone NOD mice. The delivery of the G3c mAb via G3C hybridoma cells enveloped in alginate-based microcapsules (G3C/cps) for 3 weeks induced Foxp3+ Treg-cell expansion in the spleen of wild-type mice but not in Gitr-/- mice. G3C/cps also induced the expansion of nonconventional Cd4+Cd25-/lowFoxp3lowGitrint/high (GITR single-positive [sp]) Tregs. Both Cd4+Cd25+GitrhighFoxp3+ and GITRsp Tregs (including also antigen-specific cells) were expanded in the spleen and pancreas of G3C/cps-treated NOD mice, and the number of intact islets was higher in G3C/cps-treated than in empty cps-treated and untreated animals. Consequently, all but two G3C/cps-treated mice did not develop diabetes and all but one survived until the end of the 24-week study. In conclusion, long-term Gitr triggering induces Treg expansion, thereby delaying/preventing diabetes development in NOD mice. This therapeutic approach may have promising clinical potential for the treatment of inflammatory and autoimmune diseases.


Assuntos
Anticorpos Monoclonais , Encapsulamento de Células , Diabetes Mellitus Tipo 1/prevenção & controle , Proteína Relacionada a TNFR Induzida por Glucocorticoide/metabolismo , Hibridomas , Linfócitos T Reguladores/fisiologia , Animais , Proliferação de Células , Ensaio de Imunoadsorção Enzimática , Feminino , Regulação da Expressão Gênica , Proteína Relacionada a TNFR Induzida por Glucocorticoide/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout
5.
Isr Med Assoc J ; 21(7): 454-459, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31507120

RESUMO

BACKGROUND: Platelets have the ability to influence the immune system and the inflammatory process and may be strongly involved in the whole pathogenic process of chronic inflammatory joint diseases, such as rheumatoid arthritis. They may play a significant role even before the clinical onset of the disease, contributing to the loss of tolerance of the immune system and the induction of autoimmunity. Subsequently, they can interact with the most important cellular players involved in autoimmunity and inflammation, namely innate immunity cells and T cells and eventually contribute to the building of inflammation in the synovium, thus inducing the activation, migration, and proliferation of fibroblasts that eventually lead to joint damage. Due to their peculiar features, studying the behavior of platelets is a challenging task; however, platelets may prove to be valuable therapeutic targets in the future.


Assuntos
Artrite Reumatoide/imunologia , Plaquetas/imunologia , Sinovite/imunologia , Artrite Reumatoide/patologia , Autoimunidade/imunologia , Fibroblastos/imunologia , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Inflamação/patologia , Membrana Sinovial/imunologia , Membrana Sinovial/patologia , Sinovite/patologia , Linfócitos T/imunologia
6.
Open Forum Infect Dis ; 6(4): ofz112, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30968058

RESUMO

BACKGROUND: Experimental CCR5 antagonism with maraviroc in atherosclerosis-prone mice and preliminary data in humans suggest an anti-atherosclerotic effect of the drug. We assessed the impact of maraviroc treatment in persons living with HIV on subclinical indicators of atherosclerosis. METHODS: Persons living with HIV on effective antiretroviral therapy (ART) including only protease inhibitors were recruited if they had a Framingham risk score >20% and brachial flow-mediated dilation (bFMD) <4%, as indices of high cardiovascular risk. Maraviroc (300 mg per os for 24 weeks) was administered, in addition to ongoing ART, to all patients using a crossover design. Brachial FMD, carotid-femoral pulse wave velocity (cfPWV), and carotid intima-media thickness (cIMT) were measured as markers of atherosclerosis. Vascular competence-as expressed by the ratio of circulating endothelial microparticles (EMPs) to endothelial progenitor cells (EPCs)-and markers of systemic inflammation and monocyte and platelet activation were assessed. RESULTS: Maraviroc treatment significantly improved bFMD, cfPWV, and cIMT by 66%, 11%, and 13%, respectively (P = .002, P = .022, P = .038, respectively). We also found a beneficial effect of maraviroc on the EMP/EPC ratio (P < .001) and platelet/leucocyte aggregates (P = .013). No significant changes in markers of systemic inflammation, monocyte activation, and microbial translocation were observed. CONCLUSIONS: Maraviroc led to significant improvements in several markers for cardiovascular risk, endothelial dysfunction, arterial stiffness, and early carotid atherosclerosis, which was accompanied by an increase of vascular competence, without seeming to affect systemic inflammation. Our data support the need for larger studies to test for any effects of maraviroc on preventing atherosclerosis-driven pathologies.

7.
Clin Exp Rheumatol ; 37 Suppl 118(3): 36-41, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30336792

RESUMO

OBJECTIVES: The mechanisms underlying increased cardiovascular risk in primary Sjögren's syndrome (pSS) remain unclear. Since the recently discovered angiogenic T cells (Tang) may participate in endothelial repair by cooperating with endothelial progenitor cells (EPC), we aimed to quantify and characterise Tang in the peripheral blood and minor salivary glands (MSG) of pSS patients. METHODS: Tang (CD3+CD31+CXCR4+) and EPC (CD34+CD133+VEGFR-2+) were quantified by flow cytometry in peripheral blood samples from 36 pSS patients and 20 healthy donors. Tang subsets were assessed on the basis of CD4, CD8 and CD28 expression. Labial MSG sections from 10 pSS patients and 12 non-pSS sicca syndrome controls were subjected to immunofluorescence staining to investigate the presence of Tang and the expression of the CXCR4-ligand stromal cell-derived factor-1 (SDF-1)/CXCL12. RESULTS: Circulating Tang cells were expanded and directly correlated to EPC in pSS. Both Tang and EPC directly correlated with disease activity as calculated with the EULAR Sjögren's syndrome disease activity index (ESSDAI). In pSS, the majority of Tang cells were CD4-CD8- double negative (DN) and lacked CD28 revealing a senescent phenotype. A subset of CD4+, CD8+ and DN Tang cells produced interleukin-17. Immunohistology revealed the exclusive presence of periductal and perivascular infiltrating Tang cells along with increased SDF-1/CXCL12 expression in pSS MSG compared to non-pSS sicca syndrome controls. CONCLUSIONS: In pSS, Tang cells are expanded in peripheral blood and infiltrate MSG. Tang may be novel actors in pSS-related endothelial dysfunction and glandular neo-angiogenesis and inflammation.


Assuntos
Síndrome de Sjogren , Linfócitos T Reguladores/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Inflamação , Glândulas Salivares/imunologia , Glândulas Salivares Menores , Transdução de Sinais , Síndrome de Sjogren/sangue , Síndrome de Sjogren/etiologia , Síndrome de Sjogren/imunologia , Linfócitos T Reguladores/citologia
8.
Inflamm Bowel Dis ; 24(1): 123-135, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29272492

RESUMO

Background: The DNAX adaptor protein 12 (DAP12) is a transmembrane adaptor molecule that signals through the activation of Syk (Spleen Tyrosine Kinase) in myeloid cells. The purpose of this study is to investigate the role of DAP12 and Syk pathways in inflammatory bowel diseases (IBDs). Methods: DAP12 deficient and DAP12 transgenic, overexpressing an increased amount of DAP12, mice and Syk deficient mice in the C57/BL6 background were used for these studies. Colitis was induced by administering mice with dextran sulfate sodium (DSS), in drinking water, or 2,4,6-trinitrobenzene sulfonic acid (TNBS), by intrarectal enema. Results: Abundant expression of DAP12 and Syk was detected in colon samples obtained from Crohn's disease patients with expression restricted to immune cells infiltrating the colonic wall. In rodents development of DSS colitis as measured by assessing severity of wasting diseases, global colitis score,and macroscopic and histology scores was robustly attenuated in DAP12-/- and Syk-/- mice. In contrast, DAP12 overexpression resulted in a striking exacerbation of colon damage caused by DSS. Induction of colon expression of proinflammatory cytokines and chemokines in response to DSS administration was attenuated in DAP12-/- and Syk-/- mice, whereas opposite results were observed in DAP12 transgenic mice. Treating wild-type mice with a DAP-12 inhibitor or a Syk inhibitor caused a robust attenuation of colitis induced by DSS and TNBS. Conclusions: DAP12 and Syk are essential mediators in inflammation-driven immune dysfunction in murine colitides. Because DAP12 and Syk expression is upregulated in patients with active disease, present findings suggest a beneficial role for DAP12 and Syk inhibitors in IBD.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Inflamação/prevenção & controle , Doenças Inflamatórias Intestinais/fisiopatologia , Enteropatias/prevenção & controle , Cetotifeno/farmacologia , Estilbenos/farmacologia , Quinase Syk/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Adulto , Animais , Antipruriginosos/farmacologia , Colite/induzido quimicamente , Colite/genética , Colite/prevenção & controle , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/etiologia , Inflamação/genética , Enteropatias/etiologia , Enteropatias/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Quinase Syk/antagonistas & inibidores
9.
Sci Rep ; 7(1): 13689, 2017 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-29057935

RESUMO

Gpbar1 is a bile acid activated receptor for secondary bile acids. Here we have investigated the mechanistic role of Gpbar1 in the regulation of adipose tissues functionality in a murine model of steatohepatitis (NASH). Feeding wild type and Gpbar1-/- mice with a high fat diet-fructose (HFD-F) lead to development of NASH-like features. Treating HFD-F mice with 6ß-ethyl-3a,7b-dihydroxy-5b-cholan-24-ol (BAR501), a selective Gpbar1-ligand, reversed insulin resistance and histologic features of NASH, increased the weight of epWAT and BAT functionality and promoted energy expenditure and the browning of epWAT as assessed by measuring expression of Ucp1 and Pgc-1α. The beneficial effects of BAR501 were lost in Gpbar1-/- mice. In vitro, BAR501 promoted the browning of 3T3-L1 cells a pre-adipocyte cell line and recruitment of CREB to the promoter of Pgc-1α. In conclusion, Gpbar1 agonism ameliorates liver histology in a rodent model of NASH and promotes the browning of white adipose tissue.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Células 3T3 , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/patologia , Animais , Colestanóis/farmacologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Fígado Gorduroso/patologia , Frutose , Resistência à Insulina/fisiologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regiões Promotoras Genéticas , Substâncias Protetoras/farmacologia , Distribuição Aleatória , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo
10.
Front Pharmacol ; 8: 505, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28804459

RESUMO

Background: In addition to strain taxonomy, the ability of probiotics to confer beneficial effects on the host rely on a number of additional factors including epigenetic modulation of bacterial genes leading to metabolic variability and might impact on probiotic functionality. Aims: To investigate metabolism and functionality of two different batches of a probiotic blend commercialized under the same name in Europe in models of intestinal inflammation. Methods: Boxes of VSL#3, a probiotic mixture used in the treatment of pouchitis, were obtained from pharmacies in UK subjected to metabolomic analysis and their functionality tested in mice rendered colitis by treatment with DSS or TNBS. Results: VSL#3-A (lot DM538), but not VSL#3-B (lot 507132), attenuated "clinical" signs of colitis in the DSS and TNBS models. In both models, VSL#3-A, but not VSL#3-B, reduced macroscopic scores, intestinal permeability, and expression of TNFα, IL-1ß, and IL-6 mRNAs, while increased the expression of TGFß and IL-10, occludin, and zonula occludens-1 (ZO-1) mRNAs and shifted colonic macrophages from a M1 to M2 phenotype (P < 0.05 vs. TNBS). In contrast, VSL#3-B failed to reduce inflammation, and worsened intestinal permeability in the DSS model (P < 0.001 vs. VSL#3-A). A metabolomic analysis of the two formulations allowed the identification of two specific patterns, with at least three-folds enrichment in the concentrations of four metabolites, including 1-3 dihydroxyacetone (DHA), an intermediate in the fructose metabolism, in VSL#3-B supernatants. Feeding mice with DHA, increased intestinal permeability. Conclusions: Two batches of a commercially available probiotic show divergent metabolic activities. DHA, a product of probiotic metabolism, increases intestinal permeability, highlighting the complex interactions between food, microbiota, probiotics, and intestinal inflammation.

11.
Nanomedicine ; 13(8): 2575-2585, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28756094

RESUMO

A creation of nanotraps that could selectively recognize the chemotactic mediators of leukocyte adhesion and eliminate them from the bloodstream and tissue intercellular matrix is a promising approach for the treatment of various inflammatory and autoimmune diseases. We designed nanotraps as artificial decoy receptors based on poly(lactic acid) (PLA) nanoparticles covered by heparin and bearing on the surface two fragments of CCR5 receptor (N-terminal domain, Nt, and second extracellular loop, ECL2), responsible for chemokine binding. In order to attach Nt and ECL2 to the heparin shell, the corresponding peptides were modified with N- and/or C-terminal oligolysines. The presence of the nanotraps in the cell medium completely eliminated the activating effect of a CCR5 ligand, chemokine Rantes, while strongly decreasing the adhesion of monocytes to the human endothelial cells. We found that the modified ECL2 alone was also able to prevent monocyte adhesion, thus acting as a decoy receptor itself.


Assuntos
Materiais Biomiméticos/química , Quimiocinas/isolamento & purificação , Proteínas Imobilizadas/química , Receptores CCR5/química , Biomimética , Adesão Celular , Células Hep G2 , Heparina/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/terapia , Modelos Moleculares , Nanomedicina , Poliésteres/química , Propriedades de Superfície
12.
J Immunol ; 199(2): 718-733, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28607110

RESUMO

GPBAR1 (TGR5 or M-BAR) is a G protein-coupled receptor for secondary bile acids that is highly expressed in monocytes/macrophages. In this study, we aimed to determine the role of GPBAR1 in mediating leukocyte trafficking in chemically induced models of colitis and investigate the therapeutic potential of BAR501, a small molecule agonist for GPBAR1. These studies demonstrated that GPBAR1 gene ablation enhanced the recruitment of classically activated macrophages in the colonic lamina propria and worsened the severity of inflammation. In contrast, GPBAR1 activation by BAR501 reversed intestinal inflammation in the trinitrobenzenesulfonic acid and oxazolone models by reducing the trafficking of Ly6C+ monocytes from blood to intestinal mucosa. Exposure to BAR501 shifted intestinal macrophages from a classically activated (CD11b+, CCR7+, F4/80-) to an alternatively activated (CD11b+, CCR7-, F4/80+) phenotype, reduced the expression of inflammatory genes (TNF-α, IFN-γ, IL-1ß, IL-6, and CCL2 mRNAs), and attenuated the wasting syndrome and severity of colitis (≈70% reduction in the Colitis Disease Activity Index). The protective effect was lost in Gpbar1-/- mice. Exposure to BAR501 increased the colonic expression of IL-10 and TGF-ß mRNAs and the percentage of CD4+/Foxp3+ cells. The beneficial effects of BAR501 were lost in Il-10-/- mice. In a macrophage cell line, regulation of IL-10 by BAR501 was GPBAR1 dependent and was mediated by the recruitment of CREB to its responsive element in the IL-10 promoter. In conclusion, GPBAR1 is expressed in circulating monocytes and colonic macrophages, and its activation promotes a IL-10-dependent shift toward an alternatively activated phenotype. The targeting of GPBAR1 may offer therapeutic options in inflammatory bowel diseases.


Assuntos
Colite/imunologia , Regulação da Expressão Gênica/imunologia , Mucosa Intestinal/imunologia , Macrófagos/imunologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Antígenos Ly/genética , Antígenos Ly/imunologia , Linhagem Celular , Movimento Celular , Quimiocina CCL2/genética , Quimiocina CCL2/imunologia , Colestanóis/administração & dosagem , Colestanóis/farmacologia , Colite/induzido quimicamente , Colite/metabolismo , Inflamação/imunologia , Interleucina-10/deficiência , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Ativação de Macrófagos , Macrófagos/efeitos dos fármacos , Camundongos , Mucosa/imunologia , Oxazolona/administração & dosagem , Fenótipo , Regiões Promotoras Genéticas , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/genética , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Ácido Trinitrobenzenossulfônico/administração & dosagem , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
13.
Front Pharmacol ; 8: 162, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28424617

RESUMO

Bile acid (BA) receptors represent well-defined targets for the development of novel therapeutic approaches to metabolic and inflammatory diseases. In the present study, we report the generation of novel C-3 modified 6-ethylcholane derivatives. The pharmacological characterization and molecular docking studies for the structure-activity rationalization, allowed the identification of 3ß-azido-6α-ethyl-7α-hydroxy-5ß-cholan-24-oic acid (compound 2), a potent and selective FXR agonist with a nanomolar potency in transactivation assay and high efficacy in the recruitment of SRC-1 co-activator peptide in Alfa Screen assay. In vitro, compound 2 was completely inactive towards common off-targets such as the nuclear receptors PPARα, PPARγ, LXRα, and LXRß and the membrane G-coupled BA receptor, GPBAR1. This compound when administered in vivo exerts a robust FXR agonistic activity increasing the liver expression of FXR-target genes including SHP, BSEP, OSTα, and FGF21, while represses the expression of CYP7A1 gene that is negatively regulated by FXR. Collectively these effects result in a significant reshaping of BA pool in mouse. In summary, compound 2 represents a promising candidate for drug development in liver and metabolic disorders.

14.
Sci Rep ; 7: 42801, 2017 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-28202906

RESUMO

Non-alcoholic steatohepatitis (NASH) is a highly prevalent chronic liver disease. Here, we have investigated whether BAR502, a non-bile acid, steroidal dual ligand for FXR and GPBAR1, reverses steato-hepatitis in mice fed a high fat diet (HFD) and fructose. After 9 week, mice on HFD gained ≈30% of b.w (P < 0.01 versus naïve) and were insulin resistant. These overweighting and insulin resistant mice were randomized to receive HFD or HFD in combination with BAR502. After 18 weeks, HFD mice developed NASH like features with severe steato-hepatitis and fibrosis, increased hepatic content of triacylglycerol and cholesterol and expression of SREPB1c, FAS, ApoC2, PPARα and γ, α-SMA, α1 collagen and MCP1 mRNAs. Treatment with BAR502 caused a ≈10% reduction of b.w., increased insulin sensitivity and circulating levels of HDL, while reduced steatosis, inflammatory and fibrosis scores and liver expression of SREPB1c, FAS, PPARγ, CD36 and CYP7A1 mRNA. BAR502 increased the expression of SHP and ABCG5 in the liver and SHP, FGF15 and GLP1 in intestine. BAR502 promoted the browning of epWAT and reduced liver fibrosis induced by CCl4. In summary, BAR502, a dual FXR and GPBAR1 agonist, protects against liver damage caused by HFD by promoting the browning of adipose tissue.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Colanos/administração & dosagem , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Células 3T3-L1 , Tecido Adiposo Branco/metabolismo , Animais , Biomarcadores/metabolismo , Tetracloreto de Carbono/toxicidade , Colanos/farmacologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Frutose/efeitos adversos , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Acoplados a Proteínas G/agonistas
15.
Sci Rep ; 7: 43290, 2017 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-28233865

RESUMO

Bile acids are extensively investigated for their potential in the treatment of human disorders. The liver X receptors (LXRs), activated by oxysterols and by a secondary bile acid named hyodeoxycholic acid (HDCA), have been found essential in the regulation of lipid homeostasis in mammals. Unfortunately, LXRα activates lipogenic enzymes causing accumulation of lipid in the liver. In addition to LXRs, HDCA has been also shown to function as ligand for GPBAR1, a G protein coupled receptor for secondary bile acids whose activation represents a promising approach to liver steatosis. In the present study, we report a library of HDCA derivatives endowed with modulatory activity on the two receptors. The lead optimization of HDCA moiety was rationally driven by the structural information on the binding site of the two targets and results from pharmacological characterization allowed the identification of hyodeoxycholane derivatives with selective agonistic activity toward LXRα and GPBAR1 and notably to the identification of the first example of potent dual LXRα/GPBAR1 agonists. The new chemical entities might hold utility in the treatment of dyslipidemic disorders.


Assuntos
Ácido Desoxicólico/química , Ácido Desoxicólico/farmacologia , Receptores X do Fígado/agonistas , Receptores Acoplados a Proteínas G/agonistas , Animais , Ácido Desoxicólico/síntese química , Humanos , Receptores X do Fígado/química , Camundongos Endogâmicos C57BL , Modelos Moleculares , Ligação Proteica , Estrutura Secundária de Proteína , Receptores Acoplados a Proteínas G/química
16.
Sci Rep ; 7: 41055, 2017 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-28117422

RESUMO

The small heterodimer partner (SHP) is an orphan nuclear receptor that lacks the DNA binding domain while conserves a putative ligand-binding site, thought that endogenous ligands for this receptor are unknown. Previous studies have determined that SHP activation protects against development of liver fibrosis a process driven by trans-differentiation and activation of hepatic stellate cells (HSCs), a miofibroblast like cell type, involved in extracellular matrix (ECM) deposition. To dissect signals involved in this activity we generated SHP-overexpressing human and rat HSCs. Forced expression of SHP in HSC-T6 altered the expression of 574 genes. By pathway and functional enrichment analyses we detected a cluster of 46 differentially expressed genes involved in HSCs trans-differentiation. Using a isoxazole scaffold we designed and synthesized a series of SHP agonists. The most potent member of this group, ISO-COOH (EC50: 9 µM), attenuated HSCs trans-differentiation and ECM deposition in vitro, while in mice rendered cirrhotic by carbon tetrachloride (CCl4) or α-naphthyl-isothiocyanate (ANIT), protected against development of liver fibrosis as measured by morphometric analysis and expression of α-SMA and α1-collagen mRNAs. In aggregate, present results identify SHP as a counter-regulatory signal for HSCs transactivation and describe a novel class of SHP agonists endowed with anti-fibrotic activity.


Assuntos
Regulação da Expressão Gênica , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , 1-Naftilisotiocianato/toxicidade , Animais , Tetracloreto de Carbono/toxicidade , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Perfilação da Expressão Gênica , Humanos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Masculino , Camundongos , Ratos
17.
Sci Rep ; 6: 30802, 2016 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-27492684

RESUMO

Targeted disruption of leukocyte trafficking to the gut represents a promising approach for the treatment of inflammatory bowel diseases (IBDs). CCR5, the shared receptor for MIP1α and ß and RANTES, is expressed by multiple leukocytes. Here, we aimed to determine the role of CCR5 in mediating leukocyte trafficking in models of colitis, and evaluate the therapeutic potential of maraviroc, an orally active CCR5 antagonist used in the treatment of CCR5-tropic HIV. Acute and chronic colitis were induced by administration of DSS or TNBS to wild-type and CCR5(-/-) mice or adoptive transfer of splenic naïve CD4(+) T-cells from wild type or CCR5(-/-) mice into RAG-1(-/-). CCR5 gene ablation reduced the mucosal recruitment and activation of CCR5-bearing CD4(+) and CD11b(+) leukocytes, resulting in profound attenuation of signs and symptoms of inflammation in the TNBS and transfer models of colitis. In the DSS/TNBS colitis and in the transfer model, maraviroc attenuated development of intestinal inflammation by selectively reducing the recruitment of CCR5 bearing leukocytes. In summary, CCR5 regulates recruitment of blood leukocytes into the colon indicating that targeting CCR5 may offer therapeutic options in IBDs.


Assuntos
Quimiocina CCL5/metabolismo , Colite/patologia , Inflamação/prevenção & controle , Mucosa Intestinal/metabolismo , Animais , Antígeno CD11b/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/transplante , Quimiocina CCL5/antagonistas & inibidores , Quimiocina CCL5/genética , Quimiocinas/antagonistas & inibidores , Colite/induzido quimicamente , Colo/fisiologia , Cicloexanos/farmacologia , Cicloexanos/uso terapêutico , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Proteínas de Homeodomínio/genética , Inflamação/imunologia , Inflamação/metabolismo , Leucócitos/citologia , Leucócitos/metabolismo , Maraviroc , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Th17/citologia , Células Th17/imunologia , Triazóis/farmacologia , Triazóis/uso terapêutico , Ácido Trinitrobenzenossulfônico/toxicidade , Regulação para Cima/efeitos dos fármacos
18.
Oncotarget ; 7(38): 61021-61035, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27409173

RESUMO

GPBAR1 (also known as TGR5) is a bile acid activated receptor expressed in several adenocarcinomas and its activation by secondary bile acids increases intestinal cell proliferation. Here, we have examined the expression of GPBAR1 in human gastric adenocarcinomas and investigated whether its activation promotes the acquisition of a pro-metastatic phenotype. By immunohistochemistry and RT-PCR analysis we found that expression of GPBAR1 associates with advanced gastric cancers (Stage III-IV). GPBAR1 expression in tumors correlates with the expression of N-cadherin, a markers of epithelial-mesenchymal transition (EMT) (r=0.52; P<0.01). Expression of GPBAR1, mRNA and protein, was detected in cancer cell lines, with MKN 45 having the higher expression. Exposure of MKN45 cells to GPBAR1 ligands, TLCA, oleanolic acid or 6-ECDCA (a dual FXR and GPBAR1 ligand) increased the expression of genes associated with EMT including KDKN2A, HRAS, IGB3, MMP10 and MMP13 and downregulated the expression of CD44 and FAT1 (P<0.01 versus control cells). GPBAR1 activation in MKN45 cells associated with EGF-R and ERK1 phosphorylation. These effects were inhibited by DFN406, a GPBAR1 antagonist, and cetuximab. GPBAR1 ligands increase MKN45 migration, adhesion to peritoneum and wound healing. Pretreating MKN45 cells with TLCA increased propensity toward peritoneal dissemination in vivo. These effects were abrogated by cetuximab. In summary, we report that GPBAR1 is expressed in advanced gastric cancers and its expression correlates with markers of EMT. GPBAR1 activation in MKN45 cells promotes EMT. These data suggest that GPBAR1 antagonist might have utility in the treatment of gastric cancers.


Assuntos
Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Receptores Acoplados a Proteínas G/metabolismo , Neoplasias Gástricas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos CD/metabolismo , Caderinas/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ácido Quenodesoxicólico/análogos & derivados , Ácido Quenodesoxicólico/química , Feminino , Células Hep G2 , Humanos , Receptores de Hialuronatos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Transplante de Neoplasias , Ácido Oleanólico/química , Peritônio/metabolismo , Neoplasias Gástricas/genética , Cicatrização
19.
Sci Rep ; 6: 19008, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26740187

RESUMO

Bile acids are the endogenous modulators of the nuclear receptor FXR and the membrane receptor GPBAR1. FXR represents a promising pharmacological target for the treatment of cholestatic liver disorders. Currently available semisynthetic bile acid derivatives cover the same chemical space of bile acids and therefore they are poorly selective toward BA receptors, increasing patient risk for adverse side effects. In this report, we have investigated around the structure of CDCA describing the synthesis and the in vitro and in vivo pharmacological characterization of a novel family of compounds modified on the steroidal tetracyclic core and on the side chain. Pharmacological characterization resulted in the identification of several potent and selective FXR agonists. These novel agents might add utility in the treatment of cholestatic disorders by potentially mitigating side effects linked to unwanted activation of GPBAR1.


Assuntos
Ácidos Cólicos/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Ácidos Cólicos/síntese química , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Células Hep G2 , Humanos , Concentração Inibidora 50 , Camundongos Endogâmicos C57BL , Receptores Acoplados a Proteínas G/agonistas , Ativação Transcricional/efeitos dos fármacos
20.
Steroids ; 105: 59-67, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26607331

RESUMO

Bile acids, the end products of cholesterol metabolism, activate multiple mechanisms through the interaction with membrane G-protein coupled receptors including the bile acid receptor GPBAR1 and nuclear receptors such as the bile acid sensor, farnesoid X receptor (FXR). Even if dual FXR/GPBAR1 agonists are largely considered a novel opportunity in the treatment of several liver and metabolic diseases, selective targeting of one of these receptors represents an attractive therapeutic approach for a wide range of disorders in which dual modulation is associated to severe side effects. In the present study we have investigated around the structure of LCA generating a small library of cholane derivatives, endowed with dual FXR agonism/GPBAR1 antagonism. To the best of our knowledge, this is the first report of bile acid derivatives able to antagonize GPBAR1.


Assuntos
Ácidos e Sais Biliares/farmacologia , Ácidos Cólicos/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Ácidos e Sais Biliares/química , Ácidos Cólicos/química , Células HEK293 , Células Hep G2 , Humanos , Receptores Citoplasmáticos e Nucleares/genética , Receptores Acoplados a Proteínas G/genética , Ativação Transcricional/efeitos dos fármacos
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