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1.
Circ Res ; 127(7): e166-e183, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32588751

RESUMO

RATIONALE: Ca2+ signaling is a key and ubiquitous actor of cell organization and its modulation controls many cellular responses. SERCAs (sarco-endoplasmic reticulum Ca2+-ATPases) pump Ca2+ into internal stores that play a major role in the cytosolic Ca2+ concentration rise upon cell activation. Platelets exhibit 2 types of SERCAs, SERCA2b and SERCA3 (SERCA3 deficient mice), which may exert specific roles, yet ill-defined. We have recently shown that Ca2+ mobilization from SERCA3-dependent stores was required for full platelet activation in weak stimulation conditions. OBJECTIVE: To uncover the signaling mechanisms associated with Ca2+ mobilization from SERCA3-dependent stores leading to ADP secretion. METHODS AND RESULTS: Using platelets from wild-type or Serca3-deficient mice, we demonstrated that an early (within 5-10 s following stimulation) secretion of ADP specifically dependent on SERCA3 stored Ca2+ is exclusively mobilized by nicotinic acid adenosine dinucleotide-phosphate (NAADP): both Ca2+ mobilization from SERCA3-dependent stores and primary ADP secretion are blocked by the NAADP receptor antagonist Ned-19, and reciprocally both are stimulated by permeant NAADP. In contrast, Ca2+ mobilization from SERCA3-dependent stores and primary ADP secretion were unaffected by inhibition of the production of IP3 (inositol-1,4,5-trisphosphate) by phospholipase-C and accordingly were not stimulated by permeant IP3. CONCLUSIONS: Upon activation, an NAADP/SERCA3 Ca2+ mobilization pathway initiates an early ADP secretion, potentiating platelet activation, and a secondary wave of ADP secretion driven by both an IP3/SERCA2b-dependent Ca2+ stores pathway and the NAADP/SERCA3 pathway. This does not exclude that Ca2+ mobilized from SERCA3 stores may also enhance platelet global reactivity to agonists. Because of its modulating effect on platelet activation, this NAADP-SERCA3 pathway may be a relevant target for anti-thrombotic therapy. Graphic Abstract: A graphic abstract is available for this article.


Assuntos
Difosfato de Adenosina/sangue , Comunicação Autócrina , Plaquetas/enzimologia , Sinalização do Cálcio , NADP/análogos & derivados , Ativação Plaquetária , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Animais , Comunicação Autócrina/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Humanos , Inositol 1,4,5-Trifosfato/sangue , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADP/sangue , Ativação Plaquetária/efeitos dos fármacos , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Via Secretória , Trombina/farmacologia , Tromboxano A2/sangue , Fatores de Tempo
3.
Sci Rep ; 9(1): 18751, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822776

RESUMO

Septic shock is a systemic inflammation associated with cell metabolism disorders and cardiovascular dysfunction. Increases in O-GlcNAcylation have shown beneficial cardiovascular effects in acute pathologies. We used two different rat models to evaluate the beneficial effects of O-GlcNAc stimulation at the early phase of septic shock. Rats received lipopolysaccharide (LPS) to induce endotoxemic shock or saline (control) and fluid resuscitation (R) with or without O-GlcNAc stimulation (NButGT-10 mg/kg) 1 hour after shock induction. For the second model, rats received cecal ligature and puncture (CLP) surgery and fluid therapy with or without NButGT. Cardiovascular function was evaluated and heart and blood samples were collected and analysed. NButGT treatment efficiently increased total O-GlcNAc without modification of HBP enzyme expression.Treatment improved circulating parameters and cardiovascular function in both models, and restored SERCA2a expression levels. NButGT treatment also reduced animal mortality. In this study, we demonstrate that in septic shock O-GlcNAc stimulation improves global animal and cardiovascular function outcomes associated with a restoration of SERCA2a levels. This pre-clinical study opens avenues for a potential therapy of early-stage septic shock.


Assuntos
Acetilglucosamina/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Choque Séptico/terapia , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Modelos Animais de Doenças , Hidratação , Humanos , Lipopolissacarídeos/imunologia , Masculino , Ratos , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Choque Séptico/sangue , Choque Séptico/imunologia , Choque Séptico/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo
4.
Thromb Haemost ; 119(3): 384-396, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30650444

RESUMO

In obesity, platelets are described as hyperactive, mainly based on increased platelet size and presence of pro-thrombotic plasmatic molecules. We explored platelet functions, including calcium signalling in obesity, and the effect of weight loss. We included 40 obese patients (women with body mass index [BMI] of ≥ 35 kg/m2) who were to undergo gastric bypass surgery and 40 healthy lean subjects (women with BMI of < 25 kg/m2) as a control group. Approximately 1 year after surgery, the obese patients lost weight (75% had a BMI < 35 kg/m2). They were explored a second time with the same healthy control for the same platelet experiments. Compared with controls, obese patients' platelets displayed reduced sensitivity to thrombin (aggregation EC50 increased by 1.9 ± 0.3-fold, p = 0.005) and a lower Ca2+ response (70 ± 7% decrease, p < 10-4). In 17 pairs of patients, we performed additional experiments: in obese patients' platelets, thrombin-induced αIIbß3 activation was significantly lower (p = 0.003) and sarco-endoplasmic reticulum Ca2+ATPase (SERCA3) expression was decreased (48 ± 6% decrease, p < 10-4). These differences were abolished after weight loss. Interestingly, pharmacological inhibition of SERCA3 activity in control group's platelets mimicked similar alterations than in obese patients' platelets and was associated with defective adenosine diphosphate (ADP) secretion. Addition of ADP to agonist restored platelet functions in obese patients and in SERCA3-inhibited control platelets (five experiments) confirming the direct involvement of the SERCA3-dependent ADP secretion pathway. This is the first study demonstrating that platelets from obese patients are hypo-reactive, due to a deficiency of SERCA3-dependent ADP secretion. Weight loss restores SERCA3 activity and subsequent calcium signalling, αIIbß3 activation, platelet aggregation and ADP secretion.


Assuntos
Difosfato de Adenosina/sangue , Plaquetas/metabolismo , Derivação Gástrica , Obesidade/cirurgia , Ativação Plaquetária , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Redução de Peso , Adulto , Sinalização do Cálcio , Feminino , Humanos , Obesidade/sangue , Obesidade/diagnóstico , Obesidade/fisiopatologia , Paris , Agregação Plaquetária , Testes de Função Plaquetária , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Via Secretória , Fatores de Tempo , Resultado do Tratamento
5.
Mol Cell Biochem ; 442(1-2): 19-28, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28884444

RESUMO

The cardiac sarco/endoplasmic reticulum Ca2+-ATPase-2a (SERCA2a) is vital for the correct handling of calcium concentration in cardiomyocytes. Recent studies showed that the induction of endoplasmic reticulum (ER) stress (ERS) with the SERCA2 inhibitor Thapsigargin (Tg) increases the mRNA and protein levels of SERCA2a. The SERCA2 gene promoter contains an ERS response element (ERSE) at position -78 bp that is conserved among species and might transcriptionally regulate SERCA2 gene expression. However, its involvement in SERCA2 basal and calcium-mediated transcriptional activation has not been elucidated. In this work, we show that in cellular cultures of neonatal rat ventricular myocytes, the treatment with Tg or the calcium ionophore A23187 increases the SERCA2a mRNA and protein abundance, as well as the transcriptional activity of two chimeric human SERCA2 gene constructs, containing -254 and -2579 bp of 5'-regulatory region cloned in the pGL3-basic vector and transiently transfected in cultured cardiomyocytes. We found that the ERSE present in the SERCA2 proximal promoter contains a CCAAT box that is involved in basal and ERS-mediated hSERCA2 transcriptional activation. The EMSA results showed that the CCAAT box present in the ERSE recruits the NF-Y transcription factor. Additionally, by ChIP assays, we confirmed in vivo binding of NF-Y and C/EBPß transcription factors to the SERCA2 gene proximal promoter.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Regulação da Expressão Gênica/fisiologia , Miócitos Cardíacos/metabolismo , Elementos de Resposta , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Transcrição Gênica/fisiologia , Animais , Calcimicina/farmacologia , Ionóforos de Cálcio/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Ratos , Ratos Wistar , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Tapsigargina/farmacologia , Transcrição Gênica/efeitos dos fármacos
6.
Biochem Biophys Res Commun ; 493(4): 1471-1477, 2017 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-28986259

RESUMO

Platelets are anucleate cells, known for their pivotal roles in hemostasis, inflammation, immunity, and disease progression. Being anuclear, platelets are known to express several transcriptional factors which exert nongenomic functions, including the positive and negative regulation of platelet activation. NF-κB is one such transcriptional factor involved in the regulation of genes for survival, proliferation, inflammation and immunity. Although, the role NF-κB in platelet activation and aggregation is partially known, its function in management of platelet survival and apoptosis remain unexplored. Therefore, two unrelated inhibitors of NF-κB activation, BAY 11-7082 and MLN4924 were used to determine the role of NF-κB in platelets. Inhibition of NF-κB caused decreased SERCA activity and increased cytosolic Ca2+ level causing ER stress which was determined by the phosphorylation of eIF2-α. Further, there was increased BAX and decreased BCl-2 levels, incidence of mitochondrial membrane potential depolarization, release of cytochrome c into cytosol, caspase activation, PS externalization and cell death in BAY 11-7082 and MLN4924 treated platelets. The obtained results demonstrate the critical role played by NF-κB in Ca2+ homeostasis and survival of platelets. In addition, the study demonstrates the potential side effects associated with NF-κB inhibitors employed during inflammation and cancer therapy.


Assuntos
Apoptose/fisiologia , Plaquetas/citologia , Plaquetas/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , NF-kappa B/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Cálcio/sangue , Ciclopentanos/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , NF-kappa B/sangue , Nitrilas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/sangue , Pirimidinas/farmacologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Sulfonas/farmacologia , Proteína X Associada a bcl-2/sangue
7.
Dis Markers ; 2017: 8405196, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28928601

RESUMO

The chronic high-dose right ventricular apical (RVA) pacing may have deleterious effects on left ventricular (LV) systolic function. We hypothesized that the expression changes of genes regulating cardiomyocyte energy metabolism and contractility were associated with deterioration of LV function in patients who underwent chronic RVA pacing. Sixty patients with complete atrioventricular block and preserved ejection fraction (EF) who underwent pacemaker implantation were randomly assigned to either RVA pacing (n = 30) group or right ventricular outflow tract (RVOT) pacing (n = 30) group. The mRNA levels of OPA1 and SERCA2a were significantly lower in the RVA pacing group at 1 month's follow-up (both p < 0.001). Early changes in the expression of selected genes OPA1 and SERCA2a were associated with deterioration in global longitudinal strain (GLS) that became apparent months later (p = 0.002 and p = 0.026, resp.) The altered expressions of genes that regulate cardiomyocyte energy metabolism and contractility measured in the peripheral blood at one month following pacemaker implantation were associated with subsequent deterioration in LV dyssynchrony and function in patients with preserved LVEF, who underwent RVA pacing.


Assuntos
Ventrículos do Coração/metabolismo , Marca-Passo Artificial/efeitos adversos , Função Ventricular Esquerda , Idoso , Biomarcadores/sangue , Metabolismo Energético , Feminino , GTP Fosfo-Hidrolases/sangue , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Ventrículos do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Miócitos Cardíacos/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
8.
Arterioscler Thromb Vasc Biol ; 36(6): 1164-73, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27079884

RESUMO

OBJECTIVE: Thiol isomerases facilitate protein folding in the endoplasmic reticulum, and several of these enzymes, including protein disulfide isomerase and ERp57, are mobilized to the surface of activated platelets, where they influence platelet aggregation, blood coagulation, and thrombus formation. In this study, we examined the synthesis and trafficking of thiol isomerases in megakaryocytes, determined their subcellular localization in platelets, and identified the cellular events responsible for their movement to the platelet surface on activation. APPROACH AND RESULTS: Immunofluorescence microscopy imaging was used to localize protein disulfide isomerase and ERp57 in murine and human megakaryocytes at various developmental stages. Immunofluorescence microscopy and subcellular fractionation analysis were used to localize these proteins in platelets to a compartment distinct from known secretory vesicles that overlaps with an inner cell-surface membrane region defined by the endoplasmic/sarcoplasmic reticulum proteins calnexin and sarco/endoplasmic reticulum calcium ATPase 3. Immunofluorescence microscopy and flow cytometry were used to monitor thiol isomerase mobilization in activated platelets in the presence and absence of actin polymerization (inhibited by latrunculin) and in the presence or absence of membrane fusion mediated by Munc13-4 (absent in platelets from Unc13d(Jinx) mice). CONCLUSIONS: Platelet-borne thiol isomerases are trafficked independently of secretory granule contents in megakaryocytes and become concentrated in a subcellular compartment near the inner surface of the platelet outer membrane corresponding to the sarco/endoplasmic reticulum of these cells. Thiol isomerases are mobilized to the surface of activated platelets via a process that requires actin polymerization but not soluble N-ethylmaleimide-sensitive fusion protein attachment receptor/Munc13-4-dependent vesicular-plasma membrane fusion.


Assuntos
Plaquetas/enzimologia , Membrana Celular/enzimologia , Megacariócitos/enzimologia , Ativação Plaquetária , Isomerases de Dissulfetos de Proteínas/sangue , Actinas/sangue , Animais , Plaquetas/efeitos dos fármacos , Proteínas Sanguíneas/deficiência , Proteínas Sanguíneas/genética , Calnexina/sangue , Membrana Celular/efeitos dos fármacos , Genótipo , Humanos , Megacariócitos/efeitos dos fármacos , Fusão de Membrana , Proteínas de Membrana/sangue , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Ativação Plaquetária/efeitos dos fármacos , Isomerases de Dissulfetos de Proteínas/biossíntese , Transporte Proteico , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue
9.
Europace ; 17(10): 1563-70, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25851726

RESUMO

AIM: Long-term right ventricular apical (RVA) pacing may lead to left ventricular (LV) remodelling and heart failure. This study assessed changes in the expression of genes regulating LV contractile function and hypertrophy, after permanent RVA pacing and investigated whether such changes proceed or even predict LV remodelling. METHODS AND RESULTS: We enrolled 52 consecutive patients (age 79.1 ± 7.7 years, 34 males) who underwent pacemaker implantation for bradycardic indications: Group A, 24 individuals with atrioventricular conduction disturbances and group B, 28 patients with sinus node disease. In group A, peripheral blood mRNA levels of gene sarcoplasmic reticulum calcium ATPase decreased at 3, 6, and 12 months' follow-up, while α-myosin heavy chain (MHC) decreased and ß-MHC increased until 6 months follow-up. In this group, 25% of patients demonstrated significant LV remodelling. At 4 years, LV end-systolic diameter increased from 29.67 ± 3.39 mm at baseline to 35.38 ± 4.22 mm, LV end-diastolic diameter increased from 50 ± 4.95 to 56.71 ± 5.52 mm, and ejection fraction declined from 63.04 ± 10.22 to 52.83 ± 10.81%. Early alterations in gene expression were associated with a deterioration in LV function and geometry that became apparent months later. In group B, echocardiographic indexes and mRNA levels of the evaluated genes demonstrated no statistically significant changes. CONCLUSIONS: Permanent RVA pacing in patients with preserved ejection fraction is associated with alterations in the expression of genes regulating LV contractile function and hypertrophy, measured in the peripheral blood. These alterations are traceable at an early stage, before echocardiographic changes are apparent and are associated with LV remodelling that becomes evident in the long term.


Assuntos
Miosinas Cardíacas/sangue , Ventrículos do Coração/fisiopatologia , Cadeias Pesadas de Miosina/sangue , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Síndrome do Nó Sinusal/complicações , Função Ventricular Esquerda/genética , Remodelação Ventricular/genética , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Bradicardia/terapia , Estimulação Cardíaca Artificial/métodos , Ecocardiografia , Feminino , Insuficiência Cardíaca/terapia , Humanos , Masculino , Marca-Passo Artificial , Estudos Prospectivos , Volume Sistólico
10.
Klin Lab Diagn ; (5): 39-42, 2013 May.
Artigo em Russo | MEDLINE | ID: mdl-24006643

RESUMO

The immune-enzyme system of testing was developed to detect the level of Ca2+ ATPase of sarcoplasmic reticulum using monoclonal IgM and IgG antibodies to Ca2+ ATPase. The clinical approbation of the technique was carried out using the sample of 19 patients with acute cardiac infarction Q validated by the increase of content of such common markers of myocardium necrosis as troponin T and creatine phosphokinase MB. The increase of the level of Ca2+ ATPase of sarcoplasmic reticulum was detected in all patients. This occurrence is detected approximately in 4-6 hours after debut and it disappears in 144 hours (6 days). At the same time, Ca2+ ATPase was not detected in 10 Patients with acute traumatic damages of skeleton musculature, in 10 patients with chronic renal failure under hemodialysis and in 20 patients with acute coronary syndrome without rise of ST-segment of cardiogram. These facts testify rather high specificity and sensitivity of the developed technique of detection of the level of Ca2+ ATPase of sarcoplasmic reticulum in blood as biological marker of myocardium necrosis.


Assuntos
Infarto do Miocárdio/diagnóstico , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Adulto , Biomarcadores/sangue , Creatina Quinase Forma MB/sangue , Ensaio de Imunoadsorção Enzimática , Humanos , Infarto do Miocárdio/patologia , Necrose , Troponina/sangue
11.
Int J Cardiol ; 153(1): 36-41, 2011 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-20880599

RESUMO

BACKGROUND: There are few experimental models of heart failure (HF) in large animals, despite structural and functional similarities to human myocardium. We have developed a porcine model of chronic tachycardia-induced cardiomyopathy. METHODS: Homogenous siblings of White Large breed swine (n=6) underwent continuous right ventricular (RV) pacing at 170 bpm; 2 subjects served as controls. In the course of RV pacing, animals developed a clinical picture of HF and were presented for euthanasia at subsequent stages: mild, moderate and end-stage HF. Left ventricle (LV) sections were analyzed histologically and relative ANP, BNP, phospholamban and sarcoplasmic reticulum calcium ATPase 2a transcript levels in LV were quantified by real time RT-PCR. RESULTS: In the course of RV pacing, animals demonstrated reduced exercise capacity (time of running until being dyspnoeic: 6.6 ± 0.5 vs. 2.4 ± 1.4 min), LV dilatation (LVEDD: 4.9 ± 0.4 vs. 6.7 ± 0.4 cm), impaired LV systolic function (LVEF: 69 ± 8 vs. 32 ± 7 %), (all baseline vs. before euthanasia, all p<0.001). LV tissues from animals with moderate and end-stage HF demonstrated local foci of interstitial fibrosis, congestion, cardiomyocyte hypertrophy and atrophy, which was not detected in controls and mild HF animals. The up-regulation of ANP and BNP and a reduction in a ratio of sarcoplasmic reticulum calcium ATPase 2a and phospholamban in failing myocardium were observed as compared to controls. CONCLUSIONS: In pigs, chronic RV pacing at relatively low rate can be used as an experimental model of HF, as it results in a gradual deterioration of exercise tolerance accompanied by myocardial remodeling confirmed at subcellular level.


Assuntos
Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Modelos Animais de Doenças , Taquicardia/complicações , Taquicardia/metabolismo , Animais , Fator Natriurético Atrial/biossíntese , Fator Natriurético Atrial/sangue , Estimulação Cardíaca Artificial/métodos , Cardiomiopatias/enzimologia , Doença Crônica , Teste de Esforço/métodos , Feminino , Peptídeo Natriurético Encefálico/biossíntese , Peptídeo Natriurético Encefálico/sangue , Distribuição Aleatória , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/biossíntese , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Suínos , Taquicardia/enzimologia
12.
Eur J Dermatol ; 20(3): 271-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20423818

RESUMO

ATP2A2 encodes the sarco/endoplasmic reticulum Ca2+- ATPase (SERCA2) and has been identified as a defective gene in Darier disease (DD). It is an autosomal dominant genodermatosis, which is characterized by loss of adhesion between suprabasal epidermal keratinocytes (acantholysis) and abnormal keratinization (dyskeratosis). We examined 28 Slovenian patients with DD (the cohort of patients represents over 50% of all DD patients in Slovenia) and screened genomic DNA for ATP2A2 mutations and RNA for splice site mutations. We identified 7 different ATP2A2 mutations, 4 of which are novel: A516P, R559G, 544+1del6, and 1762-6del18. We also found two previously described polymorphisms 2741+54 G>A in intron XVIII and 2172 G>A (A724A) in exon 15, with allele frequencies of 64.2% and 11.3%, respectively. The mutations are scattered throughout the gene and affect the actuator, phosphorylation, stalk and transmembrane domains of SERCA2. A P160L mutation in a Slovene patient with severe DD and a history of deafness is another consistent genotype-phenotype correlation. It seems that mutations of the ATP2A2 gene may also play a role in the pathogenesis of deafness, which seems to be a new phenotypic characteristic of DD patients.


Assuntos
Doença de Darier/genética , Mutação , RNA/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Adolescente , Adulto , Idoso , Doença de Darier/enzimologia , Doença de Darier/epidemiologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Eslovênia/epidemiologia , Adulto Jovem
13.
Biochim Biophys Acta ; 1793(10): 1614-22, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19631699

RESUMO

Store-operated Ca(2+) entry (SOCE) is a major mechanism for Ca(2+) influx in platelets and other cells activated by a reduction in Ca(2+) concentration in the intracellular stores. SOCE has been reported to be regulated by extracellular Ca(2+), although the underlying mechanism remains unclear. Here we have examined the involvement of plasma membrane-located STIM1 (PM-STIM1) in the regulation of SOCE by extracellular Ca(2+). Treatment of platelets with the SERCA inhibitor thapsigargin (TG) induced Mn(2+) entry, which was inhibited by extracellular Ca(2+) in a concentration-dependent manner. Incubation of platelets with a specific antibody, which recognizes the extracellular amino acid sequence 25-139 of PM-STIM1 that contains the Ca(2+)-binding domain, prevented the inactivation of Ca(2+) entry induced by extracellular Ca(2+). TG induced translocation of STIM1 to the plasma membrane (PM), an event that was found to be Ca(2+)-dependent. In addition, TG stimulated association of PM-STIM1 with Orai1, an event that was not prevented by stabilization of the membrane cytoskeleton using jasplakinolide. These findings suggest that PM-STIM1 is important for the inactivation of SOCE by extracellular Ca(2+), an event that is likely to be mediated by interaction with Orai1.


Assuntos
Plaquetas/metabolismo , Sinalização do Cálcio/fisiologia , Proteínas de Membrana/sangue , Proteínas de Neoplasias/sangue , Plaquetas/efeitos dos fármacos , Cálcio/metabolismo , Cálcio/farmacologia , Canais de Cálcio/sangue , Sinalização do Cálcio/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Inibidores Enzimáticos/farmacologia , Líquido Extracelular/metabolismo , Humanos , Técnicas In Vitro , Manganês/metabolismo , Proteína ORAI1 , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/antagonistas & inibidores , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Molécula 1 de Interação Estromal , Tapsigargina/farmacologia
14.
Arch Oral Biol ; 54(4): 322-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19230861

RESUMO

This study was designed to investigate the effects of oestrogen on sarcoplasmic reticulum (SR) Ca(2+)-ATPase activity and gene expression in ovariectomised rats under the condition of chronic intermittent hypoxia (CIH). Thirty-two female Sprague-Dawley rats were randomly divided into four groups: the normal control group (NC), the CIH group (CIH), the CIH-ovariectomised group (CIH+OVX), and the group of CIH-ovariectomised rats receiving estradiol replacement (CIH+OVX+E(2)). Rats in the latter three groups were exposed to CIH for 5 weeks. The animals were killed before genioglossus (GG) was rapidly excised, and their body and uterus mass were determined. Estradiol level was detected by radioimmunoassay. SR Ca(2+)-ATPase (SERCA) activity was observed by detecting inorganic phosphorus ion, and the SERCA mRNA level was measured using real-time quantitative polymerase chain reaction (real-time PCR). It was found that, compared with the NC group, the SERCA activity and mRNA level were remarkably reduced (p<.01) in the CIH group. And compared with the CIH group, the SERCA activity and mRNA level were also significantly reduced (p<.01) in the CIH+OVX group. Meanwhile, the SERCA activity and mRNA level significantly increased (p<.01) in the CIH+OVX+E(2) group compared with the CIH+OVX group, but lower than those in the NC group (p<.01). The results showed that CIH could reduce the SERCA activity and mRNA expression, and oestrogen-deficiency could exacerbate this effect; whilst estradiol replacement can partially reverse the effect of CIH in ovariectomised rats.


Assuntos
Estradiol/farmacologia , Estrogênios/deficiência , Hipóxia/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Animais , Estradiol/sangue , Feminino , Expressão Gênica/efeitos dos fármacos , Ovariectomia , RNA Mensageiro/sangue , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética
15.
J Card Fail ; 14(10): 873-80, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19041052

RESUMO

BACKGROUND: In heart failure, alterations in the expression of proteins relevant to calcium homeostasis are involved in depressed contractility and diminished relaxation. However the regulation of genes expression is only partially known. The aim was to assess expression of calcium regulatory proteins in left ventricle (LV) myocardium characterised by a preserved global function in mitral valve stenosis (MVS) model but increased neurohumoral/cytokine (N/C) activation. METHODS AND RESULTS: Plasma N/C activation was evaluated in MVS-patients (n = 27), where expression of calcium regulatory proteins (L-type channel, sarcoplasmic reticulum Ca2+-ATPase type2 - SERCA2, Na+/Ca2+ exchanger -NCX, calsequestrin, phospholamban) in LV myocardium was assessed (Western Blot) in comparison with non-failing hearts (NFH). Out of all proteins assessed in MVS, only SERCA2 and NCX expression revealed highly variable changes between subjects, with significant reduction of SERCA2 (15%) level compared to NFH. Moreover, SERCA2 was negatively correlated with BNP (univariate/regression analysis r = -0.63, P = 0.005/r2 = 0.74, P <0.001, respectively), whereas NCX was positively correlated only with noradrenaline (univariate/stepwise analysis r = 0.59 P = 0.002/r2 = 0.59; P = 0.003). CONCLUSIONS: In MVS-patients LV becomes remodelled, although its global function is preserved. It seems that apart from alterations in LV load and wall stress, also such neurohumoral factors as BNP/noradrenaline may influence the Ca2+ handling proteins expression.


Assuntos
Proteínas de Ligação ao Cálcio/biossíntese , Proteínas de Ligação ao Cálcio/sangue , Regulação da Expressão Gênica/fisiologia , Estenose da Valva Mitral/sangue , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Canais de Cálcio Tipo L/biossíntese , Canais de Cálcio Tipo L/sangue , Canais de Cálcio Tipo L/genética , Calsequestrina/biossíntese , Calsequestrina/sangue , Calsequestrina/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/biossíntese , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Trocador de Sódio e Cálcio/biossíntese , Trocador de Sódio e Cálcio/sangue , Trocador de Sódio e Cálcio/genética , Adulto Jovem
16.
Gene Ther ; 15(23): 1550-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18650850

RESUMO

Abnormal excitation-contraction coupling is a key pathophysiologic component of heart failure (HF), and at a molecular level reduced expression of the sarcoplasmic reticulum (SR) Ca(2+) ATPase (SERCA2a) is a major contributor. Previous studies in small animals have suggested that restoration of SERCA function is beneficial in HF. Despite this promise, the means by which this information might be translated into potential clinical application remains uncertain. Using a recently established cardiac-directed recirculating method of gene delivery, we administered adeno-associated virus 2 (AAV2)/1SERCA2a to sheep with pacing-induced HF. We explored the effects of differing doses of AAV2/1SERCA2a (low 1 x 10(10) d.r.p.; medium 1 x 10(12) d.r.p. and high 1 x 10(13) d.r.p.) in conjunction with an intra-coronary delivery group (2.5 x 10(13) d.r.p.). At the end of the study, haemodynamic, echocardiographic, histopathologic and molecular biologic assessments were performed. Cardiac recirculation delivery of AAV2/1SERCA2a elicited a dose-dependent improvement in cardiac performance determined by left ventricular pressure analysis, (+d P/d t(max); low dose -220+/-70, P>0.05; medium dose 125+/-53, P<0.05; high dose 287+/-104, P<0.05) and echocardiographically (fractional shortening: low dose -3+/-2, P>0.05; medium dose 1+/-2, P>0.05; high dose 6.5+/-3.9, P<0.05). In addition to favourable haemodynamic effects, brain natriuretic peptide expression was reduced consistent with reversal of the HF molecular phenotype. In contrast, direct intra-coronary infusion did not elicit any effect on ventricular function. As such, AAV2/1SERCA2a elicits favourable functional and molecular actions when delivered in a mechanically targeted manner in an experimental model of HF. These observations lay a platform for potential clinical translation.


Assuntos
Terapia Genética/métodos , Insuficiência Cardíaca/terapia , Miocárdio/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Animais , Estimulação Cardíaca Artificial , Circulação Coronária , Dependovirus/genética , Relação Dose-Resposta a Droga , Ecocardiografia , Expressão Gênica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Fígado/virologia , Pulmão/virologia , Modelos Animais , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/análise , Distribuição Aleatória , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Ovinos , Tempo , Transdução Genética/métodos , Transgenes
17.
Cardiovasc Res ; 72(3): 438-46, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17026973

RESUMO

OBJECTIVES: Hypercholesterolemia contributes to coronary artery disease progression but little is known about its effect on left ventricular (LV) function after myocardial infarction (MI). The aim of this study was to investigate the effects of hypercholesterolemia and statin treatment in rabbits with experimental MI. METHODS AND RESULTS: New Zealand White rabbits on a normal or cholesterol-rich diet for 4 weeks, underwent permanent coronary artery ligation. Starting on the first day post-MI rabbits were treated with either placebo or simvastatin (5 mg/kg/day) for 9 weeks. Hypercholesterolemia itself did not affect LV function in sham-operated animals but further impaired LV systolic (dP/dtmax -42%) and diastolic (dP/dtmin -47%) function in MI rabbits on placebo. Simvastatin treatment not only prevented deterioration of LV function associated with hypercholesterolemia but improved LV function (dP/dtmax +130%; dP/dtmin +144%, P < 0.05). Simvastatin also attenuated the depression of LV function in normocholesterolemic MI rabbits (dP/dtmax +46%; dP/dtmin +53%, P < 0.05). Hypercholesterolemia in MI rabbits coincided with a significant increase in C-reactive protein levels (marker of inflammation) and Rac1-GTPase activity (marker of oxidative stress), and a reduction in cardiac sarcoplasmic-reticulum calcium ATPase-2 expression and endothelial nitric oxide synthase protein phosphorylation, all of which were normalised by simvastatin treatment. Elevated serum cholesterol levels were only partially reduced by simvastatin. CONCLUSIONS: Hypercholesterolemia further impaired the depressed LV function in rabbits post-MI. Statin treatment reversed this effect, and conferred additional protection, as in normocholesterolemic animals. Our study suggests that anti-inflammatory and anti-oxidative effects of simvastatin substantially contribute to its beneficial effects on cardiac function after MI.


Assuntos
Anti-Inflamatórios/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Infarto do Miocárdio/tratamento farmacológico , Sinvastatina/uso terapêutico , Disfunção Ventricular Esquerda/tratamento farmacológico , Animais , Biomarcadores/sangue , Proteína C-Reativa/análise , Dieta , Ecocardiografia , Hipercolesterolemia/imunologia , Hipercolesterolemia/fisiopatologia , Masculino , Modelos Animais , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/fisiopatologia , Óxido Nítrico Sintase Tipo III/sangue , Coelhos , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/sangue , Disfunção Ventricular Esquerda/imunologia , Disfunção Ventricular Esquerda/fisiopatologia , Proteínas rac1 de Ligação ao GTP/sangue
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