RESUMO
Growth differentiation factor 11 (GDF11) is a member of the transforming growth factor beta 1 (TGF-ß1) superfamily that reverses age-related cardiac hypertrophy, improves muscle regeneration and angiogenesis, and maintains progenitor cells in injured tissue. Recently, targeted myocardial delivery of the GDF11 gene in aged mice was found to reduce heart failure and enhance the proliferation of cardiac progenitor cells after myocardial ischemia-reperfusion (I-R). No investigations have as yet explored the cardioprotective effect of exogenous recombinant GDF11 in acute I-R injury, despite the convenience of its clinical application. We sought to determine whether exogenous recombinant GDF11 protects against acute myocardial I-R injury and investigate the underlying mechanism in Sprague-Dawley rats. We found that GDF11 reduced arrhythmia severity and successfully attenuated myocardial infarction; GDF11 also increased cardiac function after I-R, enhanced HO-1 expression and decreased oxidative damage. GDF11 activated the canonical TGF-ß signaling pathway and inactivated the non-canonical pathways, ERK and JNK signaling pathways. Moreover, administration of GDF11 prior to reperfusion protected the heart from reperfusion damage. Notably, pretreatment with the activin-binding protein, follistatin (FST), inhibited the cardioprotective effects of GDF11 by blocking its activation of Smad2/3 signaling and its inactivation of detrimental TGF-ß signaling. Our data suggest that exogenous GDF11 has cardioprotective effects and may have morphologic and functional recovery in the early stage of myocardial I-R injury. GDF11 may be an innovative therapeutic approach for reducing myocardial I-R injury.
Assuntos
Fatores de Diferenciação de Crescimento/uso terapêutico , Coração/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fator de Crescimento Transformador beta/metabolismo , Animais , Apoptose/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Proteína Forkhead Box O3/metabolismo , Fatores de Diferenciação de Crescimento/farmacologia , Heme Oxigenase (Desciclizante)/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Proteínas Smad Reguladas por Receptor/metabolismoRESUMO
Purpose: The purpose of this study was to evaluate the effect of uveitis on the development of various keratopathies via the use of the National Health Insurance Research Database (NHIRD) in Taiwan. Methods: Approximately 1 million patients were randomly sampled from the registry of the NHIRD. Patients diagnosed with uveitis by ophthalmologists were enrolled in the study group after exclusion. Each individual in the study group was age and sex matched to four non-uveitis individuals who serve as the control group. In addition to keratopathy, other possible risk factors and medications were included in the multivariate model, and the effects of different subtypes of uveitis for developing keratopathies were also analyzed. Results: A total of 4773 uveitis patients (2662 male and 2111 female) and 19,092 non-uveitis patients (10,648 male and 8444 female) were enrolled. There were 406 events of keratopathy in the study group, and another 764 events occurred in the control group. A higher incidence rate was found in the study group after adjustment (adjusted hazard ratio [aHR]: 1.772), with a greater cumulative probability (P < 0.0001). For the subgroup analysis, anterior uveitis (aHR = 1.765) and panuveitis (aHR = 3.386) increased the risk of developing keratopathies. Moreover, male sex was associated with a higher aHR than female sex for developing keratopathies in the study group. Conclusions: The presence of uveitis significantly elevates the risk for developing keratopathy.