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1.
Immunity ; 55(2): 290-307.e5, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35090581

RESUMO

Tbet+CD11c+ B cells arise during type 1 pathogen challenge, aging, and autoimmunity in mice and humans. Here, we examined the developmental requirements of this B cell subset. In acute infection, T follicular helper (Tfh) cells, but not Th1 cells, drove Tbet+CD11c+ B cell generation through proximal delivery of help. Tbet+CD11c+ B cells developed prior to germinal center (GC) formation, exhibiting phenotypic and transcriptional profiles distinct from GC B cells. Fate tracking revealed that most Tbet+CD11c+ B cells developed independently of GC entry and cell-intrinsic Bcl6 expression. Tbet+CD11c+ and GC B cells exhibited minimal repertoire overlap, indicating distinct developmental pathways. As the infection resolved, Tbet+CD11c+ B cells localized to the marginal zone where splenic retention depended on integrins LFA-1 and VLA-4, forming a competitive memory subset that contributed to antibody production and secondary GC seeding upon rechallenge. Therefore, Tbet+CD11c+ B cells comprise a GC-independent memory subset capable of rapid and robust recall responses.


Assuntos
Linfócitos B/imunologia , Antígenos CD11/metabolismo , Subpopulações de Linfócitos/imunologia , Células T Auxiliares Foliculares/imunologia , Proteínas com Domínio T/metabolismo , Viroses/imunologia , Animais , Anticorpos Antivirais/metabolismo , Linfócitos B/metabolismo , Diferenciação Celular/imunologia , Centro Germinativo/imunologia , Alphainfluenzavirus/imunologia , Integrinas/metabolismo , Subpopulações de Linfócitos/metabolismo , Vírus da Coriomeningite Linfocítica/imunologia , Células B de Memória/imunologia , Células B de Memória/metabolismo , Camundongos , Baço/imunologia
2.
J Immunol ; 210(12): 1861-1865, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37133336

RESUMO

Tbet+CD11c+ B cells, also known as age-associated B cells (ABCs), are pivotal contributors to humoral immunity following infection and in autoimmunity, yet their in vivo generation is incompletely understood. We used a mouse model of systemic acute lymphocytic choriomeningitis virus infection to examine the developmental requirements of ABCs that emerged in the spleen and liver. IL-21 signaling through STAT3 was indispensable for ABC development. In contrast, IFN-γ signaling through STAT1 was required for B cell activation and proliferation. Mice that underwent splenectomy or were deficient in lymphotoxin α generated hepatic ABCs despite the lack of secondary lymphoid organ contributions, suggesting that the liver supported de novo generation of these cells separately from their development in lymphoid organs. Thus, IFN-γ and IL-21 signaling have distinct, stage-specific roles in ABC differentiation, while the tissue microenvironment provides additional cues necessary for their development.


Assuntos
Interleucinas , Coriomeningite Linfocítica , Camundongos , Animais , Camundongos Knockout , Diferenciação Celular , Camundongos Endogâmicos C57BL
3.
Ann Rheum Dis ; 83(9): 1181-1188, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-38653530

RESUMO

OBJECTIVES: Patients with chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature/proteasome-associated autoinflammatory syndrome (CANDLE/PRAAS) respond to the janus kinase inhibitor 1/2 inhibition with baricitinib at exposures higher than in rheumatoid arthritis. Baricitinib dose reductions to minimise exposure triggered disease flares which we used to develop 'flare criteria'. METHODS: Of 10 patients with CANDLE/PRAAS treated with baricitinib in an open-label expanded-access programme, baricitinib doses were reduced 14 times in 9 patients between April 2014 and December 2019. Retrospective data analysis of daily diary scores and laboratory markers collected before and after the dose reductions were used to develop 'clinical' and 'subclinical' flare criteria. Disease flare rates were compared among patients with <25% and >25% dose reductions and during study visits when patients received recommended 'optimized' baricitinib doses (high-dose visits) versus lower than recommended baricitinib doses (low-dose visits) using two-sided χ2 tests. RESULTS: In the 9/10 patients with CANDLE with dose reduction, 7/14 (50%) times the dose was reduced resulted in a disease flare. All four dose reductions of >25% triggered a disease flare (p <0.05). Assessment of clinical and laboratory changes during disease flares allowed the development of disease flare criteria that were assessed during visits when patients received high or low doses of baricitinib. Disease flare criteria were reached during 43.14% of low-dose visits compared with 12.75% of high-dose visits (p <0.0001). Addition of an interferon score as an additional flare criterion increased the sensitivity to detect disease flares. CONCLUSION: We observed disease flares and rebound inflammation with baricitinib dose reductions and proposed flare criteria that can assist in monitoring disease activity and in designing clinical studies in CANDLE/PRAAS.


Assuntos
Azetidinas , Redução da Medicação , Purinas , Pirazóis , Sulfonamidas , Humanos , Purinas/administração & dosagem , Pirazóis/administração & dosagem , Pirazóis/uso terapêutico , Sulfonamidas/administração & dosagem , Sulfonamidas/uso terapêutico , Azetidinas/administração & dosagem , Azetidinas/uso terapêutico , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Exacerbação dos Sintomas , Lipodistrofia , Inibidores de Janus Quinases/administração & dosagem , Inibidores de Janus Quinases/uso terapêutico , Doenças Hereditárias Autoinflamatórias/tratamento farmacológico , Doenças Hereditárias Autoinflamatórias/diagnóstico , Relação Dose-Resposta a Droga
4.
J Genet Couns ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38410885

RESUMO

Genetic counselors (GCs) are trained to help individuals navigate the medical and psychological implications of genetic test results, familial conditions, and ultrasound anomalies. Therefore, familiarity with reproductive options, including abortion, is vital. However, previous studies have found gaps in GCs' knowledge regarding abortion care and there are currently no recommendations regarding abortion curriculum. This study aimed to assess the state of abortion curriculum in genetic counseling graduate programs in the United States and to examine and compare the satisfaction levels of program representatives and recent graduates. Program representatives and recent graduates were invited to complete an anonymous survey evaluating the abortion curriculum, satisfaction with said curriculum, and perceived preparedness to counsel on abortion. Quantitative data from 46 program representatives and 123 recent graduates were analyzed using descriptive statistics and appropriate statistical analyses, including the Mann-Whitney U-test and the Kruskal-Wallis test. Large variability existed in the amount and types of abortion training. Results showed greater satisfaction and feelings of preparation to counsel on abortion in graduates whose program provided a dedicated abortion curriculum (p < 0.001, p = 0.005). In addition, graduates with abortion counseling experience felt less prepared to counsel on abortion than their programs believed them to be (p = 0.04). Graduates perceived procedural timing, facilitation of genetic testing, and resources/support desired by patients before, during, or after an abortion, to be the most important topics, although these were not included in all programs' curriculum. Program representatives and recent graduates alike noted that variability in clinical training is a barrier to abortion education. Our results demonstrate a need for curricular reform to reduce variability in training and ensure that all graduates receive the same foundational abortion education. Further research is needed to determine the scope of GCs in abortion care, as well as which topics and education formats are most helpful in graduate education.

5.
Ann Rheum Dis ; 81(5): 601-613, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35086813

RESUMO

OBJECTIVE: Autoinflammatory type I interferonopathies, chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature/proteasome-associated autoinflammatory syndrome (CANDLE/PRAAS), stimulator of interferon genes (STING)-associated vasculopathy with onset in infancy (SAVI) and Aicardi-Goutières syndrome (AGS) are rare and clinically complex immunodysregulatory diseases. With emerging knowledge of genetic causes and targeted treatments, a Task Force was charged with the development of 'points to consider' to improve diagnosis, treatment and long-term monitoring of patients with these rare diseases. METHODS: Members of a Task Force consisting of rheumatologists, neurologists, an immunologist, geneticists, patient advocates and an allied healthcare professional formulated research questions for a systematic literature review. Then, based on literature, Delphi questionnaires and consensus methodology, 'points to consider' to guide patient management were developed. RESULTS: The Task Force devised consensus and evidence-based guidance of 4 overarching principles and 17 points to consider regarding the diagnosis, treatment and long-term monitoring of patients with the autoinflammatory interferonopathies, CANDLE/PRAAS, SAVI and AGS. CONCLUSION: These points to consider represent state-of-the-art knowledge to guide diagnostic evaluation, treatment and management of patients with CANDLE/PRAAS, SAVI and AGS and aim to standardise and improve care, quality of life and disease outcomes.


Assuntos
Doenças Autoimunes do Sistema Nervoso , Malformações do Sistema Nervoso , Reumatologia , Dermatopatias , Eritema Nodoso , Dedos/anormalidades , Humanos , Qualidade de Vida
6.
Int J Mol Sci ; 24(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36614108

RESUMO

Cardiomyopathy is commonly observed in patients with autosomal dominant polycystic kidney disease (ADPKD), even when they have normal renal function and arterial pressure. The role of cardiomyocyte polycystin-1 (PC1) in cardiovascular pathophysiology remains unknown. PC1 is a potential regulator of BIN1 that maintains T-tubule structure, and alterations in BIN1 expression induce cardiac pathologies. We used a cardiomyocyte-specific PC1-silenced (PC1-KO) mouse model to explore the relevance of cardiomyocyte PC1 in the development of heart failure (HF), considering reduced BIN1 expression induced T-tubule remodeling as a potential mechanism. PC1-KO mice exhibited an impairment of cardiac function, as measured by echocardiography, but no signs of HF until 7-9 months of age. Of the PC1-KO mice, 43% died suddenly at 7 months of age, and 100% died after 9 months with dilated cardiomyopathy. Total BIN1 mRNA, protein levels, and its localization in plasma membrane-enriched fractions decreased in PC1-KO mice. Moreover, the BIN1 + 13 isoform decreased while the BIN1 + 13 + 17 isoform was overexpressed in mice without signs of HF. However, BIN1 + 13 + 17 overexpression was not observed in mice with HF. T-tubule remodeling and BIN1 score measured in plasma samples were associated with decreased PC1-BIN1 expression and HF development. Our results show that decreased PC1 expression in cardiomyocytes induces dilated cardiomyopathy associated with diminished BIN1 expression and T-tubule remodeling. In conclusion, positive modulation of BIN1 expression by PC1 suggests a novel pathway that may be relevant to understanding the pathophysiological mechanisms leading to cardiomyopathy in ADPKD patients.


Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , Rim Policístico Autossômico Dominante , Canais de Cátion TRPP , Animais , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Cardiomiopatia Dilatada/patologia , Insuficiência Cardíaca/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Rim Policístico Autossômico Dominante/genética , Isoformas de Proteínas/metabolismo , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
7.
Ann Rheum Dis ; 80(6): 788-795, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33619160

RESUMO

BACKGROUND: Monogenic autoinflammatory diseases (AID) are caused by mutations in innate immune genes. The effects of these mutations on allergic inflammation are unknown. OBJECTIVES: We investigated allergic, immunological and clinical phenotypes in FMF (familial Mediterranean fever), CAPS (cryopyrin-associated periodic syndrome), TRAPS (tumour necrosis factor receptor-associated periodic syndrome), HIDS (hyper-IgD syndrome), PAPA (pyogenic arthritis, pyoderma gangrenosum and acne), DADA2 (deficiency of adenosine deaminase 2), HA20 (haploinsufficiency of A20), CANDLE (chronic atypical neutrophilic dermatosis, lipodystrophy, elevated temperature) and SAVI (STING-associated vasculopathy of infancy). METHODS: In this cross-sectional study, clinical data were assessed in 425 patients with AID using questionnaires and chart reviews. Comparator data were obtained from public databases. Peripheral blood mononuclear cells obtained from 55 patients were stimulated and CD4+ cytokine production assessed. RESULTS: Clinical laboratory features of Type 2 immunity were elevated in CAPS but reduced in most AID, particularly DADA2. Physician-diagnosed allergic diseases were prevalent in multiple AID, including CAPS and DADA2. T helper 2 (Th2) cells were expanded in CAPS, TRAPS and HIDS; Th9 cells were expanded in HA20. CONCLUSIONS: CAPS is characterised by an enhanced Type 2 signature, whereas FMF and CANDLE are associated with reduced Type 2 responses. DADA2 is associated with reduced Type 2 responses but a high rate of physician-diagnosed allergy. Therefore, NLRP3-driven autoinflammation may promote Type 2 immunity, whereas AID like DADA2 may manifest clinical phenotypes that masquerade as allergic disorders. Further investigations are needed to determine the contribution of autoinflammation to allergic clinical and immunological phenotypes, to improve the treatment of patients with AID.


Assuntos
Síndromes Periódicas Associadas à Criopirina , Febre Familiar do Mediterrâneo , Doenças Hereditárias Autoinflamatórias , Hipersensibilidade , Dermatopatias , Adenosina Desaminase , Estudos Transversais , Síndromes Periódicas Associadas à Criopirina/genética , Doenças Hereditárias Autoinflamatórias/diagnóstico , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Leucócitos Mononucleares , Dermatopatias/genética
8.
Int J Mol Sci ; 22(19)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34638553

RESUMO

Low-grade chronic inflammation plays a pivotal role in the pathogenesis of insulin resistance (IR), and skeletal muscle has a central role in this condition. NLRP3 inflammasome activation pathways promote low-grade chronic inflammation in several tissues. However, a direct link between IR and NLRP3 inflammasome activation in skeletal muscle has not been reported. Here, we evaluated the NLRP3 inflammasome components and their role in GLUT4 translocation impairment in skeletal muscle during IR. Male C57BL/6J mice were fed with a normal control diet (NCD) or high-fat diet (HFD) for 8 weeks. The protein levels of NLRP3, ASC, caspase-1, gasdermin-D (GSDMD), and interleukin (IL)-1ß were measured in both homogenized and isolated fibers from the flexor digitorum brevis (FDB) or soleus muscle. GLUT4 translocation was determined through GLUT4myc-eGFP electroporation of the FBD muscle. Our results, obtained using immunofluorescence, showed that adult skeletal muscle expresses the inflammasome components. In the FDB and soleus muscles, homogenates from HFD-fed mice, we found increased protein levels of NLRP3 and ASC, higher activation of caspase-1, and elevated IL-1ß in its mature form, compared to NCD-fed mice. Moreover, GSDMD, a protein that mediates IL-1ß secretion, was found to be increased in HFD-fed-mice muscles. Interestingly, MCC950, a specific pharmacological NLRP3 inflammasome inhibitor, promoted GLUT4 translocation in fibers isolated from the FDB muscle of NCD- and HFD-fed mice. In conclusion, we found increased NLRP3 inflammasome components in adult skeletal muscle of obese insulin-resistant animals, which might contribute to the low-grade chronic metabolic inflammation of skeletal muscle and IR development.


Assuntos
Transportador de Glucose Tipo 4/metabolismo , Inflamassomos/metabolismo , Resistência à Insulina/fisiologia , Interleucina-1beta/metabolismo , Músculo Esquelético/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Caspase 1/metabolismo , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Furanos/farmacologia , Indenos/farmacologia , Inflamassomos/química , Interleucina-1beta/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Obesidade/induzido quimicamente , Obesidade/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Sulfonamidas/farmacologia
9.
J Mol Cell Cardiol ; 141: 65-69, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32234389

RESUMO

Cardiac hypertrophy is an adaptive response to manage an excessive cardiac workload and maintain normal cardiac function. However, sustained hypertrophy leads to cardiomyopathy, cardiac failure, and death. Adrenergic receptors play a key role in regulating cardiac function under normal and pathological conditions. Mitochondria are responsible for 90% of ATP production in cardiomyocytes. Mitochondrial function is dynamically regulated by fusion and fission processes. Changes in mitochondrial dynamics and metabolism are central issues in cardiac hypertrophy. Stimulating cardiomyocytes with adrenergic agonists generates hypertrophy and increases mitochondrial fission, which in turn is associated with decreased ATP synthesis. Miro1 is a mitochondrial outer membrane protein involved in mitochondrial dynamics and transport in neurons. The objective of this work was to evaluate whether Miro1 regulates cardiomyocyte hypertrophy through changes in mitochondrial dynamics. In neonatal rat ventricular myocytes, we showed that phenylephrine induced cardiomyocyte hypertrophy and increased Miro1 mRNA and protein levels. Moreover, alpha-adrenergic stimulation provoked a mitochondrial fission pattern in the cardiomyocytes. Miro1 knockdown prevented both the cardiomyocyte hypertrophy and mitochondrial fission pattern. Our results suggest that Miro1 participates in phenylephrine-induced cardiomyocyte hypertrophy through mitochondrial fission.


Assuntos
Cardiomegalia/metabolismo , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteínas rho de Ligação ao GTP/metabolismo , Animais , Animais Recém-Nascidos , Cardiomegalia/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Ventrículos do Coração/citologia , Dinâmica Mitocondrial , Proteínas Mitocondriais/genética , Fenilefrina/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Proteínas rho de Ligação ao GTP/genética
13.
Pharmacol Res ; 135: 112-121, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30048754

RESUMO

Angiotensin-(19), a peptide of the non-classical renin angiotensin system, has been shown to prevent and revert hypertension and cardiac hypertrophy. We hypothetized that systemic delivery of angiotensin-(1-9) following myocardial infarction will also be protective and extend to provide protection during reperfusion of the ischemic heart. Adult Sprague Dawley rats were subjected to left anterior descending artery ligation and treated with angiotensin-(1-9) via osmotic mini-pump for 2 weeks in the presence or absence of Mas receptor or AT2R antagonists (A779 and PD123319, respectively). Myocardial death and left ventricular function were evaluated after infarction. Infarct size and functional parameters were determined in isolated rat hearts after global ischemia/reperfusion in the presence of angiotensin-(1-9) plus receptor antagonists or Akt inhibitor at reperfusion. in vitro, neonatal rat ventricular cardiomyocytes underwent simulated ischemia/reperfusion and angiotensin-(1-9) was co-incubated with A779, PD123319 or Akt inhibitor. Systemic delivery of angiotensin-(1-9) significantly decreased cell death and improved left ventricular recovery after in vivo myocardial infarction. Perfusion with the peptide reduced the infarct size and improved functional recovery after ex vivo ischemia/reperfusion. In vitro, angiotensin-(1-9) decreased cell death in isolated neonatal rat ventricular cardiomyocytes subjected to simulated ischemia/reperfusion. The cardioprotective effects of angiotensin-(1-9) were blocked by PD123319 and Akti VIII but not by A779. Angiotensin-(1-9) limits reperfusion-induced cell death by an AT2R- and Aktdependent mechanism. Angiotensin-(1-9) is a novel strategy to protect against cardiac ischemia/reperfusion injury.


Assuntos
Angiotensina I/uso terapêutico , Cardiotônicos/uso terapêutico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fragmentos de Peptídeos/uso terapêutico , Angiotensina I/farmacologia , Animais , Animais Recém-Nascidos , Cardiotônicos/farmacologia , Células Cultivadas , Coração/efeitos dos fármacos , Coração/fisiologia , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/metabolismo , Fragmentos de Peptídeos/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Receptor Tipo 2 de Angiotensina/metabolismo
14.
Neural Plast ; 2018: 5056181, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30123252

RESUMO

Hippocampus-dependent spatial and aversive memory processes entail Ca2+ signals generated by ryanodine receptor (RyR) Ca2+ channels residing in the endoplasmic reticulum membrane. Rodents exposed to different spatial memory tasks exhibit significant hippocampal RyR upregulation. Contextual fear conditioning generates robust hippocampal memories through an associative learning process, but the effects of contextual fear memory acquisition, consolidation, or extinction on hippocampal RyR protein levels remain unreported. Accordingly, here we investigated if exposure of male rats to contextual fear protocols, or subsequent exposure to memory destabilization protocols, modified the hippocampal content of type-2 RyR (RyR2) channels, the predominant hippocampal RyR isoforms that hold key roles in synaptic plasticity and spatial memory processes. We found that contextual memory retention caused a transient increase in hippocampal RyR2 protein levels, determined 5 h after exposure to the conditioning protocol; this increase vanished 29 h after training. Context reexposure 24 h after training, for 3, 15, or 30 min without the aversive stimulus, decreased fear memory and increased RyR2 protein levels, determined 5 h after reexposure. We propose that both fear consolidation and extinction memories induce RyR2 protein upregulation in order to generate the intracellular Ca2+ signals required for these distinct memory processes.


Assuntos
Medo , Hipocampo/metabolismo , Memória/fisiologia , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Animais , Condicionamento Clássico , Eletrochoque , Extinção Psicológica/fisiologia , Masculino , Consolidação da Memória/fisiologia , Ratos Sprague-Dawley , Regulação para Cima
15.
Int J Mol Sci ; 19(2)2018 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-29439404

RESUMO

Ventricular arrhythmias are a common cause of sudden cardiac death, and their occurrence is higher in obese subjects. Abnormal gating of ryanodine receptors (RyR2), the calcium release channels of the sarcoplasmic reticulum, can produce ventricular arrhythmias. Since obesity promotes oxidative stress and RyR2 are redox-sensitive channels, we investigated whether the RyR2 activity was altered in obese mice. Mice fed a high fat diet (HFD) became obese after eight weeks and exhibited a significant increase in the occurrence of ventricular arrhythmias. Single RyR2 channels isolated from the hearts of obese mice were more active in planar bilayers than those isolated from the hearts of the control mice. At the molecular level, RyR2 channels from HFD-fed mice had substantially fewer free thiol residues, suggesting that redox modifications were responsible for the higher activity. Apocynin, provided in the drinking water, completely prevented the appearance of ventricular arrhythmias in HFD-fed mice, and normalized the activity and content of the free thiol residues of the protein. HFD increased the expression of NOX4, an isoform of NADPH oxidase, in the heart. Our results suggest that HFD increases the activity of RyR2 channels via a redox-dependent mechanism, favoring the appearance of ventricular arrhythmias.


Assuntos
Arritmias Cardíacas/etiologia , Dieta Hiperlipídica/efeitos adversos , Obesidade/complicações , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Disfunção Ventricular/etiologia , Acetofenonas/uso terapêutico , Animais , Antiarrítmicos/uso terapêutico , Arritmias Cardíacas/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , NADPH Oxidase 4/metabolismo , Obesidade/etiologia , Espécies Reativas de Oxigênio/metabolismo , Disfunção Ventricular/tratamento farmacológico
16.
J Clin Immunol ; 37(5): 445-451, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28503715

RESUMO

PURPOSE: Deficiency of interleukin-1 receptor antagonist (DIRA) is a rare life-threatening autoinflammatory disease caused by autosomal recessive mutations in IL1RN. DIRA presents clinically with early onset generalized pustulosis, multifocal osteomyelitis, and elevation of acute phase reactants. We evaluated and treated an antibiotic-unresponsive patient with presumed DIRA with recombinant IL-1Ra (anakinra). The patient developed anaphylaxis to anakinra and was subsequently desensitized. METHODS: Genetic analysis of IL1RN was undertaken and treatment with anakinra was initiated. RESULTS: A 5-month-old Indian girl born to healthy non-consanguineous parents presented at the third week of life with irritability, sterile multifocal osteomyelitis including ribs and clavicles, a mild pustular rash, and elevated acute phase reactants. SNP array of the patient's genomic DNA revealed a previously unrecognized homozygous deletion of approximately 22.5 Kb. PCR and Sanger sequencing of the borders of the deleted area allowed identification of the breakpoints of the deletion, thus confirming a homozygous 22,216 bp deletion that spans the first four exons of IL1RN. Due to a clinical suspicion of DIRA, anakinra was initiated which resulted in an anaphylactic reaction that triggered desensitization with subsequent marked and sustained clinical and laboratory improvement. CONCLUSION: We report a novel DIRA-causing homozygous deletion affecting IL1RN in an Indian patient. The mutation likely is a founder mutation; the design of breakpoint-specific primers will enable genetic screening in Indian patients suspected of DIRA. The patient developed anaphylaxis to anakinra, was desensitized, and is in clinical remission on continued treatment.


Assuntos
Doenças Hereditárias Autoinflamatórias/diagnóstico , Doenças Hereditárias Autoinflamatórias/genética , Proteína Antagonista do Receptor de Interleucina 1/genética , Deleção de Sequência , Alelos , Biomarcadores , Hibridização Genômica Comparativa , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Doenças Hereditárias Autoinflamatórias/terapia , Homozigoto , Humanos , Índia , Lactente , Polimorfismo de Nucleotídeo Único , Radiografia
17.
Am J Physiol Heart Circ Physiol ; 311(3): H713-24, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27422983

RESUMO

Previous results from our laboratory showed that phosphorylation of ryanodine receptor 2 (RyR2) by Ca(2+) calmodulin-dependent kinase II (CaMKII) was a critical but not the unique event responsible for the production of reperfusion-induced arrhythmogenesis, suggesting the existence of other mechanisms cooperating in an additive way to produce these rhythm alterations. Oxidative stress is a prominent feature of ischemia/reperfusion injury. Both CaMKII and RyR2 are proteins susceptible to alteration by redox modifications. This study was designed to elucidate whether CaMKII and RyR2 redox changes occur during reperfusion and whether these changes are involved in the genesis of arrhythmias. Langendorff-perfused hearts from rats or transgenic mice with genetic ablation of CaMKII phosphorylation site on RyR2 (S2814A) were subjected to ischemia-reperfusion in the presence or absence of a free radical scavenger (mercaptopropionylglycine, MPG) or inhibitors of NADPH oxidase and nitric oxide synthase. Left ventricular contractile parameters and monophasic action potentials were recorded. Oxidation and phosphorylation of CaMKII and RyR2 were assessed. Increased oxidation of CaMKII during reperfusion had no consequences on the level of RyR2 phosphorylation. Avoiding the reperfusion-induced thiol oxidation of RyR2 with MPG produced a reduction in the number of arrhythmias and did not modify the contractile recovery. Conversely, selective prevention of S-nitrosylation and S-glutathionylation of RyR2 was associated with higher numbers of arrhythmias and impaired contractility. In S2814A mice, treatment with MPG further reduced the incidence of arrhythmias. Taken together, the results suggest that redox modification of RyR2 synergistically with CaMKII phosphorylation modulates reperfusion arrhythmias.


Assuntos
Arritmias Cardíacas/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Contração Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Potenciais de Ação , Animais , Arritmias Cardíacas/metabolismo , Western Blotting , Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/efeitos dos fármacos , Eletroforese , Sequestradores de Radicais Livres/farmacologia , Glutationa/metabolismo , Preparação de Coração Isolado , Masculino , Camundongos , Camundongos Transgênicos , Contração Miocárdica/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/metabolismo , NADPH Oxidases/antagonistas & inibidores , Óxido Nítrico Sintase/antagonistas & inibidores , Oxirredução , Estresse Oxidativo , Fosforilação , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/efeitos dos fármacos , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo , Tiopronina/farmacologia
18.
Pharmacol Res ; 103: 318-27, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26607864

RESUMO

The alpha2-adrenergic receptor agonist Dexmedetomidine (Dex) is a sedative medication used by anesthesiologists. Dex protects the heart against ischemia-reperfusion (IR) and can also act as a preconditioning mimetic. The mechanisms involved in Dex-dependent cardiac preconditioning, and whether this action occurs directly or indirectly on cardiomyocytes, still remain unclear. The endothelial nitric oxide synthase (eNOS)/nitric oxide (NO) signaling pathway and endothelial cells are known to play key roles in cardioprotection against IR injury. Therefore, the aims of this work were to evaluate whether the eNOS/NO pathway mediates the pharmacological cardiac effect of Dex, and whether endothelial cells are required in this cardioprotective action. Isolated adult rat hearts were treated with Dex (10nM) for 25min and the dimerization of eNOS and production of NO were measured. Hearts were then subjected to global IR (30/120min) and the role of the eNOS/NO pathway was evaluated. Dex promoted the activation of eNOS and production of NO. Dex reduced the infarct size and improved the left ventricle function recovery, but this effect was reversed when Dex was co-administered with inhibitors of the eNOS/NO/PKG pathway. In addition, Dex was unable to reduce cell death in isolated adult rat cardiomyocytes subjected to simulated IR. Cardiomyocyte death was attenuated by co-culturing them with endothelial cells pre-treated with Dex. In summary, our results show that Dex triggers cardiac protection by activating the eNOS/NO signaling pathway. This pharmacological effect of Dex requires its interaction with the endothelium.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Cardiotônicos/farmacologia , Dexmedetomidina/farmacologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Agonistas de Receptores Adrenérgicos alfa 2/uso terapêutico , Animais , Cardiotônicos/uso terapêutico , Células Cultivadas , Técnicas de Cocultura , Dexmedetomidina/uso terapêutico , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Masculino , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Ratos Sprague-Dawley
19.
J Am Acad Dermatol ; 74(1): 186-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26584874

RESUMO

Key teaching points • SAVI is a recently described interferonopathy resulting from constitutive action of STING and up-regulation of IFN-ß signaling. • SAVI is characterized by facial erythema with telangiectasia, acral/cold-sensitive tissue ulceration and amputations, and interstitial lung disease. It has overlapping features with Aicardi-Goutières syndrome and familial chilblain lupus. • Traditional immunosuppressive medications and biologic therapies appear to be of limited benefit, but JAK inhibitors may impact disease progression.


Assuntos
Doenças Autoimunes/diagnóstico , Interferon Tipo I/genética , Doenças Pulmonares Intersticiais/diagnóstico , Dermatopatias Vasculares/diagnóstico , Anormalidades Múltiplas/diagnóstico , Adolescente , Doenças Autoimunes/genética , Progressão da Doença , Insuficiência de Crescimento , Dedos/patologia , Humanos , Doenças Pulmonares Intersticiais/genética , Masculino , Necrose/diagnóstico , Doenças Raras , Dermatopatias Vasculares/genética , Síndrome , Dedos do Pé/patologia
20.
Biochem Biophys Res Commun ; 467(2): 451-7, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26449460

RESUMO

In the heart, insulin controls key functions such as metabolism, muscle contraction and cell death. However, all studies have been focused on insulin action during reperfusion. Here we explore the cardioprotective action of this hormone during ischemia. Rat hearts were perfused ex vivo with an ischemia/reperfusion Langendorff model in absence or presence of insulin. Additionally, cultured rat cardiomyocytes were exposed to simulated ischemia in the absence or presence of insulin. Cytoprotective effects were measured by myocardial infarct size, trypan blue exclusion, released LDH and DNA fragmentation by flow cytometry. We found that insulin protected against cardiac ischemia ex vivo and in vitro. Moreover, insulin protected cardiomyocytes from simulated ischemia by reducing necrotic cell death. Protective effects of insulin were dependent of Akt and NFκB. These novel results show that insulin reduces ischemia-induced cardiomyocyte necrosis through an Akt/NF-κB dependent mechanism. These novel findings clarify the role of insulin during ischemia and further support its use in early GIK perfusion to treat myocardial infarction.


Assuntos
Cardiotônicos/farmacologia , Insulina/farmacologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , NF-kappa B/metabolismo , Necrose/prevenção & controle , Animais , Fragmentação do DNA/efeitos dos fármacos , Expressão Gênica , Coração/efeitos dos fármacos , Coração/fisiopatologia , L-Lactato Desidrogenase/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , NF-kappa B/genética , Necrose/genética , Necrose/metabolismo , Necrose/patologia , Técnicas de Cultura de Órgãos , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
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