Cellular and molecular impact of exercise training on liver lipid infiltration

我们下一个研究项目的主要目标是了解在营养条件下（西方人的高脂肪饮食）和绝经后肝脏是如何被脂肪浸润的。我们还试图了解规律的体育锻炼是如何与这些影响相抵触的。我们有三种特权。我们首先感兴趣的是在分子基础上理解在高脂肪饮食和停止雌激素后，大鼠肝脏中新脂质的合成和氧化是如何分别被刺激和减少的。我们还对第二种方法感兴趣，即测试与肝脏脂质输出有关的特定假设。这是一个重要的考虑因素，因为它决定了循环血脂。在第三步，我们感兴趣的是评估雌激素减少（即绝经）对从心脏释放的催产素激素和房利钠肽的特定途径的影响。我们假设这两种激素对肝脏有保护作用。雌激素的退出会减少这一途径的作用，并导致有害的影响，如炎症。总的来说，我们的下一个研究项目应该会带来新的信息，关于富含脂肪的饮食如何导致肝脏中脂肪的积累，以及绝经后妇女中雌激素的减少如何以及为什么会导致肝脏中脂质的浸润。

Our main objective for our next research program is to understand how the liver gets infiltrated with fat under nutritional circumstances (westerner high-fat diet) and after menopause. We also try to understand how regular physical exercise contravenes these effects. There are three approaches that we privilege. We are first interested in understanding on a molecular basis how the synthesis of new lipids and its oxidation are respectively stimulated and reduced in liver under high-fat diets and following withdrawal of estrogens in rats. We are also interested, in a second approach, in testing specific hypotheses related to exportation of lipids from the liver. This is an important consideration since it determines circulating blood lipids. In a third step, we are interested in evaluating the impact of a reduction in estrogens (i.e. menopause) on a specific pathway involving oxytocin hormone and atrial natriuretic peptide liberated from the heart. We postulate that these two hormones have a protective effect on the liver. Withdrawal of estrogens will reduce the action of this pathway and causes deleterious effects such as inflammation. On the whole, our next research program should lead to new information regarding how diets enriched in fat leads to accumulation of fat in liver and how and why withdrawal of estrogens, as seen in post-menopausal women, also leads to infiltration of lipids in liver.