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1.
PLoS One ; 8(9): e73347, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24098634

RESUMO

Although antiretroviral treatment decreases HIV-AIDS morbidity/mortality, long-term side effects may include the onset of insulin resistance and cardiovascular diseases. However, the underlying molecular mechanisms responsible for highly active antiretroviral therapy (HAART)-induced cardio-metabolic effects are poorly understood. In light of this, we hypothesized that HIV protease inhibitor (PI) treatment (Lopinavir/Ritonavir) elevates myocardial oxidative stress and concomitantly inhibits the ubiquitin proteasome system (UPS), thereby attenuating cardiac function. Lopinavir/Ritonavir was dissolved in 1% ethanol (vehicle) and injected into mini-osmotic pumps that were surgically implanted into Wistar rats for 8 weeks vs. vehicle and sham controls. We subsequently evaluated metabolic parameters, gene/protein markers and heart function (ex vivo Langendorff perfusions). PI-treated rats exhibited increased serum LDL-cholesterol, higher tissue triglycerides (heart, liver), but no evidence of insulin resistance. In parallel, there was upregulation of hepatic gene expression, i.e. acetyl-CoA carboxylase b and 3-hydroxy-3-methylglutaryl-CoA-reductase, key regulators of fatty acid oxidation and cholesterol synthesis, respectively. PI-treated hearts displayed impaired cardiac contractile function together with attenuated UPS activity. However, there was no significant remodeling of hearts exposed to PIs, i.e. lack of ultrastructural changes, fibrosis, cardiac hypertrophic response, and oxidative stress. Western blot analysis of PI-treated hearts revealed that perturbed calcium handling may contribute to the PI-mediated contractile dysfunction. Here chronic PI administration led to elevated myocardial calcineurin, nuclear factor of activated T-cells 3 (NFAT3), connexin 43, and phosphorylated phospholamban, together with decreased calmodulin expression levels. This study demonstrates that early changes triggered by PI treatment include increased serum LDL-cholesterol levels together with attenuated cardiac function. Furthermore, PI exposure inhibits the myocardial UPS and leads to elevated calcineurin and connexin 43 expression that may be associated with the future onset of cardiac contractile dysfunction.


Assuntos
Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/farmacologia , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Análise de Variância , Animais , Western Blotting , Calcineurina/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , LDL-Colesterol/sangue , Conexina 43/metabolismo , Primers do DNA/genética , Combinação de Medicamentos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Fígado/metabolismo , Lopinavir/farmacologia , Masculino , Fatores de Transcrição NFATC/metabolismo , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Ritonavir/farmacologia , Triglicerídeos/metabolismo
2.
Immunohematology ; 27(3): 94-100, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22356548

RESUMO

April 2011 marked the 70th anniversary of the establishment of the American Red Cross Blood Services (ARCBS). In this report, we present a biography of Dr. Charles Drew, the first medical director of the ARCBS. Although many may recognize Dr. Charles Drew for this position, the research and training that led him to be uniquely qualified to take this position may not be as well known. We present his professional training, his research on blood preservation and distribution, and his service to the larger medical community and country. Lastly, we address the many myths that have arisen over the years since his untimely death at the age of 45 on April 1, 1950, and present the legacy of Dr. Charles Drew that has largely been unknown to the greater medical and scientific community.


Assuntos
Hematologia/história , Cruz Vermelha/história , Negro ou Afro-Americano , Acessibilidade aos Serviços de Saúde , História do Século XX , Humanos , Diretores Médicos , Preconceito , Estados Unidos
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