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1.
Mol Ther Methods Clin Dev ; 31: 101148, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38046198

RESUMO

Recombinant adeno-associated viruses (rAAVs) are promising gene delivery vectors in the emerging field of in vivo gene therapies. To ensure their consistent quality during manufacturing and process development, multiple analytical techniques have been proposed for the characterization and quantification of rAAV capsids. Despite their indisputable capabilities for performing this task, current analytical methods are rather time-consuming, material intensive, complicated, and costly, restricting their suitability for process development in which time and sample throughput are severe constraints. To eliminate this bottleneck, we introduce here an affinity-based high-performance liquid chromatography method that allows the determination of the capsid titer and the full/empty ratio of rAAVs within less than 5 min. By packing the commercially available AAVX affinity resin into small analytical columns, the rAAV fraction of diverse serotypes can be isolated from process-related impurities and analyzed by UV and fluorescence detection. As demonstrated by both method qualification data and side-by-side comparison with AAV enzyme-linked immunosorbent assay results for rAAV8 samples as well as by experiments using additional rAAV2, rAAV8, and rAAV9 constructs, our approach showed good performance, indicating its potential as a fast, simple and efficient tool for supporting the development of rAAV gene therapies.

2.
Pflugers Arch ; 474(10): 1069-1076, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35867189

RESUMO

Proinflammatory cytokines target vascular endothelial cells during COVID-19 infections. In particular, the endothelial glycocalyx (eGC), a proteoglycan-rich layer on top of endothelial cells, was identified as a vulnerable, vasoprotective structure during infections. Thus, eGC damage can be seen as a hallmark in the development of endothelial dysfunction and inflammatory processes. Using sera derived from patients suffering from COVID-19, we could demonstrate that the eGC became progressively worse in relation to disease severity (mild vs severe course) and in correlation to IL-6 levels. This could be prevented by administering low doses of spironolactone, a well-known and highly specific aldosterone receptor antagonist. Our results confirm that SARS-CoV-2 infections cause eGC damage and endothelial dysfunction and we outline the underlying mechanisms and suggest potential therapeutic options.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Glicocálix , Antagonistas de Receptores de Mineralocorticoides , SARS-CoV-2 , Espironolactona , COVID-19/sangue , COVID-19/patologia , Citocinas/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Glicocálix/efeitos dos fármacos , Glicocálix/patologia , Humanos , Interleucina-6/sangue , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Proteoglicanas/análise , Proteoglicanas/sangue , Espironolactona/farmacologia , Espironolactona/uso terapêutico
3.
Front Immunol ; 13: 1020844, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36713457

RESUMO

Background: The new types of mRNA-containing lipid nanoparticle vaccines BNT162b2 and mRNA-1273 and the adenovirus-based vaccine AZD1222 were developed against SARS-CoV-2 and code for its spike (S) protein. Several studies have investigated short-term antibody (Ab) responses after vaccination. Objective: However, the impact of these new vaccine formats with unclear effects on the long-term Ab response - including isotype, subclass, and their type of Fc glycosylation - is less explored. Methods: Here, we analyzed anti-S Ab responses in blood serum and the saliva of SARS-CoV-2 naïve and non-hospitalized pre-infected subjects upon two vaccinations with different mRNA- and adenovirus-based vaccine combinations up to day 270. Results: We show that the initially high mRNA vaccine-induced blood and salivary anti-S IgG levels, particularly IgG1, markedly decrease over time and approach the lower levels induced with the adenovirus-based vaccine. All three vaccines induced, contrary to the short-term anti-S IgG1 response with high sialylation and galactosylation levels, a long-term anti-S IgG1 response that was characterized by low sialylation and galactosylation with the latter being even below the corresponding total IgG1 galactosylation level. Instead, the mRNA, but not the adenovirus-based vaccines induced long-term IgG4 responses - the IgG subclass with inhibitory effector functions. Furthermore, salivary anti-S IgA levels were lower and decreased faster in naïve as compared to pre-infected vaccinees. Predictively, age correlated with lower long-term anti-S IgG titers for the mRNA vaccines. Furthermore, higher total IgG1 galactosylation, sialylation, and bisection levels correlated with higher long-term anti-S IgG1 sialylation, galactosylation, and bisection levels, respectively, for all vaccine combinations. Conclusion: In summary, the study suggests a comparable "adjuvant" potential of the newly developed vaccines on the anti-S IgG Fc glycosylation, as reflected in relatively low long-term anti-S IgG1 galactosylation levels generated by the long-lived plasma cell pool, whose induction might be driven by a recently described TH1-driven B cell response for all three vaccines. Instead, repeated immunization of naïve individuals with the mRNA vaccines increased the proportion of the IgG4 subclass over time which might influence the long-term Ab effector functions. Taken together, these data shed light on these novel vaccine formats and might have potential implications for their long-term efficacy.


Assuntos
COVID-19 , Imunoglobulina G , Humanos , SARS-CoV-2 , Vacinas contra COVID-19 , Vacina BNT162 , ChAdOx1 nCoV-19 , COVID-19/prevenção & controle , Vacinas de mRNA , Adenoviridae/genética
4.
Clin Oral Implants Res ; 32 Suppl 21: 303-317, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34642994

RESUMO

AIM: To study the time and costs involved with computer-assisted versus non-computer-assisted implant planning and placement. MATERIAL AND METHODS: Based on the PICO question, "In patients receiving dental implants, is computer-assisted implant planning and surgery (CAIPS) compared to non-computer-assisted implant planning and surgery (non-CAIPS) beneficial in terms of treatment related costs and time involved?", a search path was created to perform an electronic search in the databases PubMed, PubMed Central, EMBASE, and Cochrane. The publication period of eligible publications extended from 01.01.2005 to 04.05.2020. Four independent reviewers reviewed the literature to identify studies that met the eligibility inclusion criteria. A further manual search of articles was performed, and gray literature was excluded. Corresponding authors of potentially eligible manuscripts were contacted for further information. RESULTS: Of the 1354 retrieved titles after the search were screened. Thirty-one articles have been identified to read the full text, resulting in four articles to be analyzed for the present review all of which were RCTs. In total, 182 partially and completely edentulous patients were treated with 416 implants following either non-computer-assisted or computer-assisted implant planning and surgery to determine the duration of the single working steps and the financial aspects of the different procedures. CONCLUSIONS: When evaluating the time and costs involved with the diagnostic and planning procedures in computer-assisted implant planning and surgery workflow protocols, one can summarize that these are higher than in the non-computer-assisted workflow protocols. The time involved with the procedures appears to be the driving factor when it comes to economic considerations. On the basis of the conclusions, also the time for the prosthetic restoration should be taken into account.


Assuntos
Implantes Dentários , Cirurgia Assistida por Computador , Computadores , Implantação Dentária Endóssea , Prótese Dentária Fixada por Implante , Humanos
5.
Front Med (Lausanne) ; 8: 691618, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34291066

RESUMO

Immune checkpoint inhibitor (ICI) therapy has revolutionized the treatment of several human malignancies, particularly metastatic skin cancer. However, immune-related myocarditis (irM), an immune-mediated adverse event (irAE), is often fatal. In the absence of a reliable biomarker, measurement of pre-ICI therapy serum troponin concentration has been proposed to identify patients at risk of developing irM, although real-world studies examining this strategy are lacking. Thus, we retrospectively analyzed the case records of all patients who commenced ICI therapy between January 2018 and December 2019 in a single university skin cancer center (n = 121) to (i) determine the incidence of irM, (ii) establish the frequency of pretreatment serum hsTnT elevations, and (iii) to establish whether this identified patients who subsequently developed irM. Only one patient developed irM, resulting in an overall incidence of 0.8%. Pretreatment hsTnT was measured in 47 patients and was elevated in 13 (28%). Elevated serum hsTnT concentrations were associated with chronic renal failure (p = 0.02) and diabetes (p < 0.0002). Pretreatment hsTnT was not elevated in the patient who developed fulminant irM. Pre-immunotherapy serum hsTnT concentrations were often asymptomatically elevated in patients with advanced skin cancer, none of whom subsequently developed irM during ICI therapy. However, large studies are required to assess the positive and negative predictive values of hsTnT for the development of irM. In the meantime, elevated hsTnT concentrations should be investigated before initiation of immunotherapy and closely monitored during early treatment cycles, where the risk of irM is greatest.

6.
Am Heart J ; 234: 1-11, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33428901

RESUMO

BACKGROUND: In acute myocardial infarction complicated by cardiogenic shock the use of mechanical circulatory support devices remains controversial and data from randomized clinical trials are very limited. Extracorporeal life support (ECLS) - venoarterial extracorporeal membrane oxygenation - provides the strongest hemodynamic support in addition to oxygenation. However, despite increasing use it has not yet been properly investigated in randomized trials. Therefore, a prospective randomized adequately powered clinical trial is warranted. STUDY DESIGN: The ECLS-SHOCK trial is a 420-patient controlled, international, multicenter, randomized, open-label trial. It is designed to compare whether treatment with ECLS in addition to early revascularization with percutaneous coronary intervention or alternatively coronary artery bypass grafting and optimal medical treatment is beneficial in comparison to no-ECLS in patients with severe infarct-related cardiogenic shock. Patients will be randomized in a 1:1 fashion to one of the two treatment arms. The primary efficacy endpoint of ECLS-SHOCK is 30-day mortality. Secondary outcome measures such as hemodynamic, laboratory, and clinical parameters will serve as surrogate endpoints for prognosis. Furthermore, a longer follow-up at 6 and 12 months will be performed including quality of life assessment. Safety endpoints include peripheral ischemic vascular complications, bleeding and stroke. CONCLUSIONS: The ECLS-SHOCK trial will address essential questions of efficacy and safety of ECLS in addition to early revascularization in acute myocardial infarction complicated by cardiogenic shock.


Assuntos
Oxigenação por Membrana Extracorpórea , Infarto do Miocárdio/terapia , Revascularização Miocárdica/métodos , Ponte de Artéria Coronária/métodos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/métodos , Fibrinolíticos/uso terapêutico , Humanos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/mortalidade , Prognóstico , Estudos Prospectivos , Qualidade de Vida , Tamanho da Amostra , Choque Cardiogênico/etiologia , Choque Cardiogênico/mortalidade
7.
Artif Organs ; 44(12): 1259-1266, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32592601

RESUMO

The frequency of mechanical circulatory support (MCS) device application has increased in recent years. Besides implantation in the emergency setting, such as circulatory arrest, MCS is also increasingly used electively to ensure hemodynamic stability in high-risk patients, for example, during percutaneous coronary interventions (PCI), valve interventions or off-pump coronary bypass surgery. Lifebridge (Zoll Medical GmbH, Germany) is a compact percutaneous MCS device widely used in daily clinical routine. The present study aimed to investigate the indications, feasibility, and outcomes after use of Lifebridge in cardiac interventions, evaluating a large-scale multicenter database. A total of 60 tertiary cardiovascular centers were questioned regarding application and short-term outcomes after the use of the Lifebridge system (n = 160 patients). Out of these 60 centers, eight consented to participate in the study (n = 39 patients), where detailed data were collected using standardized questionnaires. Demographic and clinical characteristics of the patient population, procedural as well as follow-up data were recorded and analyzed. In 60 interrogated centers, Lifebridge was used in 74% of emergency cases and 26% in the setting of planned interventions. The subcohort interrogated in detail displayed the same distribution of application scenarios, while the main cardiovascular procedure was high-risk PCI (82%). All patients were successfully weaned from the device and 92% (n = 36) of the patients studied in detail survived after 30 days. As assessed 30 days after insertion of the device, bleeding requiring red blood cell (RBC) transfusion constituted the main complication, occurring in 49% of cases. In our analysis of clinical data, the use of Lifebridge in cardiac intervention was shown to be feasible. Further prospective studies are warranted to identify patients who benefit from hemodynamic MCS support despite the increased rate of RBC transfusion due to challenges in access sites during cardiovascular procedures.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Oxigenação por Membrana Extracorpórea/estatística & dados numéricos , Cuidados Intraoperatórios/métodos , Hemorragia Pós-Operatória/epidemiologia , Idoso , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Ponte de Artéria Coronária sem Circulação Extracorpórea/estatística & dados numéricos , Transfusão de Eritrócitos/estatística & dados numéricos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/instrumentação , Estudos de Viabilidade , Feminino , Seguimentos , Alemanha/epidemiologia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/estatística & dados numéricos , Mortalidade Hospitalar , Humanos , Cuidados Intraoperatórios/efeitos adversos , Cuidados Intraoperatórios/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Hemorragia Pós-Operatória/etiologia , Hemorragia Pós-Operatória/terapia , Estudos Prospectivos , Sistema de Registros/estatística & dados numéricos , Centros de Atenção Terciária/estatística & dados numéricos , Resultado do Tratamento
8.
Front Immunol ; 10: 1731, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31402914

RESUMO

Besides mediating hemostatic functions, platelets are increasingly recognized as important players of inflammation. Data from experiments in mice and men revealed various intersection points between thrombosis, hemostasis, and inflammation, which are addressed and discussed in this review in detail. One such example is the intrinsic coagulation cascade that is initiated after platelet activation thereby further propagating and re-enforcing wound healing or thrombus formation but also contributing to the pathophysiology of severe diseases. FXII of the intrinsic pathway connects platelet activation with the coagulation cascade during immune reactions. It can activate the contact system thereby either creating an inflammatory state or accelerating inflammation. Recent insights into platelet biology could show that platelets are equipped with complement receptors. Platelets are important for tissue remodeling after injury has been inflicted to the endothelial barrier and to the subendothelial tissue. Thus, platelets are increasingly recognized as more than just cells relevant for bleeding arrest. Future insights into platelet biology are to be expected. This research will potentially offer novel opportunities for therapeutic intervention in diseases featuring platelet abundance.


Assuntos
Plaquetas/imunologia , Plaquetas/metabolismo , Suscetibilidade a Doenças , Imunidade , Animais , Medula Óssea , Proteínas do Sistema Complemento/imunologia , Proteínas do Sistema Complemento/metabolismo , Humanos , Imunidade Inata , Inflamação/etiologia , Inflamação/metabolismo , Ativação Plaquetária , Glicoproteínas da Membrana de Plaquetas/metabolismo , Ligação Proteica , Transdução de Sinais , Trombopoese , Trombose/etiologia , Trombose/metabolismo
9.
Circ J ; 83(8): 1653-1659, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31257357

RESUMO

BACKGROUND: Second-generation cryoballoon (CB2)-based pulmonary vein isolation (PVI) has demonstrated encouraging results in the treatment of atrial fibrillation (AF). This study sought to assess data on the safety, efficacy and clinical success of CB2-based PVI in patients with heart failure (HF) and reduced ejection fraction (HFrEF).Methods and Results:CB2-based PVI was performed in 551 consecutive patients in 3 highly experienced EP centers. Patients with HF and LVEF ≤40% were included (HFrEF group, n=50/551, 9.1%). Data were compared with propensity score-matched patients without HF and preserved left ventricular EF (LVEF) (n=50, control group). The median LVEF was HFrEF: 37% (35, 40) and control: 55% (55, 55), P<0.0001. Major periprocedural complications were registered in 4/50 (8%, HFrEF group) and 3/50 (6%, control group), P=0.695. The 12-month freedom from AF recurrence was 73.1% (95% confidence interval (CI): 61-88, HFrEF group) and 72.6% (95% CI: 61-87, control group), P=0.25. NYHA class decreased from 2.4±0.8 (baseline) to 1.7±0.8 at 12-month follow-up (P<0.0001). LVEF improved from a median of 37% (35, 40) prior to ablation to a median of 55% (40, 55), P<0.0001. CONCLUSIONS: CB2-based PVI in patients with HFrEF appeared to be safe, was associated with comparable periprocedural complications and showed promising clinical success rates equal to those for patients with preserved LVEF. NYHA class and LVEF significantly improved at 12-month follow-up.


Assuntos
Fibrilação Atrial/cirurgia , Cateteres Cardíacos , Criocirurgia/instrumentação , Insuficiência Cardíaca/fisiopatologia , Veias Pulmonares/cirurgia , Função Ventricular Esquerda , Potenciais de Ação , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Criocirurgia/efeitos adversos , Desenho de Equipamento , Feminino , Alemanha , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Veias Pulmonares/fisiopatologia , Recuperação de Função Fisiológica , Recidiva , Estudos Retrospectivos , Fatores de Risco , Volume Sistólico , Fatores de Tempo
11.
Int J Mol Sci ; 20(9)2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31083399

RESUMO

Elevated pro-inflammatory biomarkers and cytokines are associated with morbidity and mortality in heart failure (HF). Preclinical and clinical studies have shown multiple inflammatory mechanisms causing cardiac remodeling, dysfunction and chronic failure. Therapeutics in trials targeting the immune response in heart failure and its effects did not result in evident benefits regarding clinical endpoints and mortality. This review elaborates pathways of immune cytokines in pathogenesis and worsening of heart failure in clinical and cellular settings. Besides the well-known mechanisms of immune activation and inflammation in atherosclerosis causing ischemic cardiomyopathy or myocarditis, attention is focused on other mechanisms leading to heart failure such as transthyretin (TTR) amyloidosis or heart failure with preserved ejection fraction. The knowledge of the pathogenesis in heart failure and amyloidosis on a molecular and cellular level might help to highlight new disease defining biomarkers and to lead the way to new therapeutic targets.


Assuntos
Amiloidose/complicações , Insuficiência Cardíaca/complicações , Inflamação/patologia , Isquemia Miocárdica/complicações , Pré-Albumina/metabolismo , Transdução de Sinais , Humanos
13.
Int J Cardiol ; 250: 11-15, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29169749

RESUMO

BACKGROUND: The detailed pathomechanism of Takotsubo syndrome (TS) is still elusive. Due to the predominance of postmenopausal females, a potential role of sex hormones has been suggested. However, the limited available data are contradictory. The aim of this study was to comprehensively assess the role of sex hormone levels in a large cohort of TS patients. METHODS: Serum samples of 57 female TS patients and 57 female patients with myocardial infarction (MI), matched for age (±2years) and repolarization disturbances were analyzed for estradiol (E2), estrone (E1), testosterone and androstenedione using liquid chromatography-tandem mass spectrometry. RESULTS: There was no difference concerning the concentrations of E1 [pmol/l (IQR): 89.1 (62.5, 132.0) vs. 98.8 (63.3, 156.0), p=0,441], testosterone [nmol/l (IQR): 0.67 (0.46, 1.00) vs. 0.80 (0.49, 1.08), p=0.382] and androstenedione [nmol/l (IQR): 2.03 (1.57, 3.11) vs. 2.98 (1.48, 5.27), p=0.244] between female TS and MI patients. Regarding E2, the majority of patients demonstrated concentrations below the detection limit of 30pmol/l (TS: n=41/54, 75.9%; MI: n=32/53, 60.4%; p=0.078). The remaining individuals with detectable E2 concentrations did not show a significant difference between TS and MI patients [pmol/l (IQR): 40.5 (33.0, 53.3) vs. 54.1 (37.9, 60.9); p=0.20]. CONCLUSIONS: Altered sex hormone levels, especially an estradiol deficiency, could not be identified as a risk factor for TS.


Assuntos
Androstenodiona/sangue , Estradiol/sangue , Estrona/sangue , Cardiomiopatia de Takotsubo/sangue , Cardiomiopatia de Takotsubo/diagnóstico por imagem , Testosterona/sangue , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Hormônios Esteroides Gonadais/sangue , Humanos , Masculino , Pessoa de Meia-Idade
14.
Coron Artery Dis ; 26(6): 535-44, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25968304

RESUMO

Cardiogenic shock (CS) is still the predominant cause of in-hospital death in patients with acute myocardial infarction, although mortality has been reduced in recent years. Early percutaneous coronary intervention and coronary artery bypass grafting are causal therapies implemented in CS, supported by catecholamines, fluids, intra-aortic balloon pumping, and also active percutaneous assist devices. There is only limited evidence from randomized studies of any of these treatments in CS, except for early revascularization and the relative ineffectiveness of intra-aortic balloon pumping. This review will present treatment pathways of CS complicating acute myocardial infarction, with a major focus on revascularization, intensive care unit treatment, and mechanical support devices.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Ponte de Artéria Coronária , Coração Auxiliar , Hemodinâmica , Balão Intra-Aórtico/instrumentação , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea , Choque Cardiogênico/terapia , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/mortalidade , Humanos , Balão Intra-Aórtico/efeitos adversos , Balão Intra-Aórtico/mortalidade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Desenho de Prótese , Recuperação de Função Fisiológica , Fatores de Risco , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/mortalidade , Choque Cardiogênico/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda
15.
Cardiovasc Diabetol ; 11: 57, 2012 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-22621761

RESUMO

BACKGROUND: Calcium (Ca2+) handling proteins are known to play a pivotal role in the pathophysiology of cardiomyopathy. However little is known about early changes in the diabetic heart and the impact of insulin treatment (Ins). METHODS: Zucker Diabetic Fatty rats treated with or without insulin (ZDF ± Ins, n = 13) and lean littermates (controls, n = 7) were sacrificed at the age of 19 weeks. ZDF + Ins (n = 6) were treated with insulin for the last 6 weeks of life. Gene expression of Ca2+ ATPase in the cardiac sarcoplasmatic reticulum (SERCA2a, further abbreviated as SERCA) and phospholamban (PLB) were determined by northern blotting. Ca2+ transport of the sarcoplasmatic reticulum (SR) was assessed by oxalate-facilitated 45Ca-uptake in left ventricular homogenates. In addition, isolated neonatal cardiomyocytes were stimulated in cell culture with insulin, glucose or triiodthyronine (T3, positive control). mRNA expression of SERCA and PLB were measured by Taqman PCR. Furthermore, effects of insulin treatment on force of contraction and relaxation were evaluated by cardiomyocytes grown in a three-dimensional collagen matrix (engineered heart tissue, EHT) stimulated for 5 days by insulin. By western blot phosphorylations status of Akt was determed and the influence of wortmannin. RESULTS: SERCA levels increased in both ZDF and ZDF + Ins compared to control (control 100 ± 6.2 vs. ZDF 152 ± 26.6* vs. ZDF + Ins 212 ± 18.5*# % of control, *p < 0.05 vs. control, #p < 0.05 vs. ZDF) whereas PLB was significantly decreased in ZDF and ZDF + Ins (control 100 ± 2.8 vs. ZDF 76.3 ± 13.5* vs. ZDF + Ins 79.4 ± 12.9* % of control, *p < 0.05 vs control). The increase in the SERCA/PLB ratio in ZDF and ZDF ± Ins was accompanied by enhanced Ca2+ uptake to the SR (control 1.58 ± 0.1 vs. ZDF 1.85 ± 0.06* vs. ZDF + Ins 2.03 ± 0.1* µg/mg/min, *p < 0.05 vs. control). Interestingly, there was a significant correlation between Ca2+ uptake and SERCA2a expression. As shown by in-vitro experiments, the effect of insulin on SERCA2a mRNA expression seemed to have a direct effect on cardiomyocytes. Furthermore, long-term treatment of engineered heart tissue with insulin increased the SERCA/PLB ratio and accelerated relaxation time. Akt was significantly phosphorylated by insulin. This effect could be abolished by wortmannin. CONCLUSION: The current data demonstrate that early type 2 diabetes is associated with an increase in the SERCA/PLB ratio and that insulin directly stimulates SERCA expression and relaxation velocity. These results underline the important role of insulin and calcium handling proteins in the cardiac adaptation process of type 2 diabetes mellitus contributing to cardiac remodeling and show the important role of PI3-kinase-Akt-SERCA2a signaling cascade.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Miocárdio/enzimologia , Miócitos Cardíacos/efeitos dos fármacos , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Animais , Animais Recém-Nascidos , Northern Blotting , Western Blotting , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Células Cultivadas , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatologia , Modelos Animais de Doenças , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Masculino , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/enzimologia , Fosforilação , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas c-akt , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Ratos Zucker , Retículo Sarcoplasmático/enzimologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Fatores de Tempo , Regulação para Cima
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