RESUMO
The mitochondria have an important role in modulating cell cycle progression, cell survival, and apoptosis. In the adult heart, the cardiac mitochondria have a unique spatial arrangement and occupy nearly one-third the volume of a cardiomyocyte, being highly efficient for converting the products of glucose or fatty acid metabolism into adenosine triphosphate (ATP). In cardiomyocytes, the decline of mitochondrial function reduces ATP generation and increases the production of reactive oxygen species, which generates impaired heart function. This is because mitochondria play a key role in maintaining cytosolic calcium concentration and modulation of muscle contraction, as ATP is required to dissociate actin from myosin. Beyond that, mitochondria have a significant role in cardiomyocyte apoptosis because it is evident that patients who have cardiovascular diseases (CVDs) have increased mitochondrial DNA damage to the heart and aorta. Many studies have shown that natural products have mitochondria-modulating effects in cardiac diseases, determining them as potential candidates for new medicines. This review outlines the leading plant secondary metabolites and natural compounds derived from microorganisms as modulators of mitochondrial dysfunctions associated with CVDs.
Assuntos
Produtos Biológicos , Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/metabolismo , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Trifosfato de Adenosina , Miócitos Cardíacos/metabolismoRESUMO
BACKGROUND: Concerns exist that women are underrepresented in trials of cardiovascular medications. OBJECTIVES: The authors sought to examine women's participation and the reported safety and efficacy by gender for pivotal cardiovascular disease (CVD) trials submitted to the U.S. Food and Drug Administration (FDA) supporting marketing applications. METHODS: On the basis of publicly available FDA reviews, the authors assessed enrollment of women in trials supporting 36 drug approvals from 2005 to 2015. Prevalence-corrected estimates for the participation of women were calculated as the percentage of women among trial participants divided by the percentage of women in the disease population (participation to prevalence ratio [PPR]), with a range between 0.8 and 1.2 reflecting similar representation of women in the trial and disease population. Sex differences in efficacy and safety were assessed. RESULTS: The proportion of women enrolled ranged from 22% to 81% (mean 46%). The calculated PPR by disease area was within or above the desirable range for atrial fibrillation (0.8 to 1.1), hypertension (0.9), and pulmonary arterial hypertension (1.4); PPR was <0.8 for heart failure (0.5 to 0.6), coronary artery disease (0.6), and acute coronary syndrome/myocardial infarction (0.6). The authors found little indication of clinically meaningful gender differences in efficacy or safety. Gender differences in efficacy or safety were described in labeling for 4 drugs. CONCLUSIONS: Women were well represented in trials of drugs for hypertension and atrial fibrillation, and overrepresented for pulmonary arterial hypertension. Representation of women fell below a PPR of 0.8 for trials in heart failure, coronary artery disease, and acute coronary syndrome. Minimal gender differences in drug efficacy and safety profiles were observed.
Assuntos
Fármacos Cardiovasculares , Ensaios Clínicos como Assunto/estatística & dados numéricos , Aprovação de Drogas , Feminino , Humanos , Masculino , Fatores Sexuais , MulheresRESUMO
Doxorubicin, an anthracycline antibiotic commonly used as a chemotherapeutic agent for breast cancer, is well known to cause cardiotoxicity. We report the case of an active, otherwise healthy 57-year-old breast cancer survivor who, 17 years after chemotherapy, presented with symptoms of overt heart failure. She had no cardiac risk factors, and neither laboratory nor imaging findings suggested myocarditis or dilated cardiomyopathy. Echocardiographic findings and differential diagnosis led us to attribute her condition to late doxorubicin-induced cardiomyopathy. By virtue of tapered medical therapy, her left ventricular ejection fraction improved from 0.20 to 0.55 in 8 months, and she was asymptomatic after 1 year. The reversibility of left ventricular dysfunction in our patient and the very late appearance of cardiotoxicity secondary to doxorubicin therapy raise questions about the pathogenesis and prevalence of late doxorubicin-induced cardiomyopathy and how to improve outcomes in patients who present with related symptoms of heart failure.