RESUMO
Over the past few years it has become clear that mitochondria are not merely the powerhouses of cells. Proteome-analyses of mitochondria from different organisms and organs revealed that more than 1000 proteins are localized in and/or on mitochondria. This by far exceeds the number of proteins required for classical mitochondrial functions, e.g. the respiratory chain, the tricarboxylic acid cycle, fatty acid oxidation and apoptosis. This suggests that many of these proteins have other, as yet unknown functions. Several proteins with well-described nuclear functions, like the transcription factor FoxO3A or the Telomerase Reverse Transcriptase, have recently been shown to be localized also within the mitochondria. This mini-review will focus on the description of the functions of these two proteins in the nucleus and in the mitochondria - as two examples of many more proteins, which are yet to be uncovered. It will give insights into the role of these proteins within different organelles of the cell and will reveal that the functions of the proteins are probably not the same in the nucleus and the mitochondria. Therefore, these differences have to be considered when targeting proteins for therapeutic approaches.
Assuntos
Envelhecimento/genética , Fatores de Transcrição Forkhead/genética , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Telomerase/genética , Envelhecimento/metabolismo , Animais , Núcleo Celular/genética , Núcleo Celular/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica , Humanos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Ligação Proteica , Transporte Proteico , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Telomerase/metabolismoRESUMO
The endothelium is located in a strategic anatomical position within the blood vessel wall and thus constitutes a barrier between the blood and all tissues. The integrity of the endothelial cells, which line the entire circulatory system like wallpaper, is essential to prevent the onset of cardiovascular disorders. Aging is one of the major risk factors for the development of heart and vascular diseases. However, over the past years it has become clear that the functional capacity of endothelial cells declines with age and that physiological aging occurs independently of pathological changes. One important mechanism contributing to the onset of the aging. process is the disturbance of the cellular redox homeostasis. Two key molecules involved in maintaining the delicate balance between oxidative and antioxidative systems are NADPH oxidase 4, an enzyme whose sole function is to produce reactive oxygen species and the oxidoreductase thioredoxin-1, which reduces oxidized proteins. Therefore, this review will focus on the role of these two proteins in cardiovascular aging.
