The utility of biomarkers for non-alcoholic fatty liver disease in adolescents

肝脏是人体最大的腺器官，受累的部位也很多。S正常函数。它产生在循环中分解脂肪所需的化学物质，并产生胆固醇。它将葡萄糖（糖）从循环转化为一种可以储存的形式，并负责维持循环中葡萄糖的适当水平。它还制造大量的氨基酸（蛋白质的基本组成部分），储存关键的维生素和矿物质，并过滤身体中的有害物质，如酒精。直到最近，高水平的酒精摄入被认为是发达人群中肝脏疾病的主要原因。然而，由于最近肥胖的流行，现在发达国家肝脏疾病最常见的原因是由肝脏中的脂肪沉积引起的，即所谓的非酒精性脂肪性肝病（NALFD）。来自美国的研究表明，NAFLD开始发生在青春期，在美国高达15%的健康青少年患有NAFLD。成人NAFLD可发展为肝硬化，也与糖尿病和心血管疾病的风险增加有关。然而，由于安全和准确诊断这种情况的困难，其在青少年中的原因和后果尚未得到广泛研究。诊断NAFLD最准确的方法是从肝脏中取样本（活检）并在显微镜下检查。然而，这种方法有潜在的危险，而且成本很高，不适合大规模的研究。包括超声扫描在内的许多扫描方法也有助于准确诊断，但对于大规模研究来说，这些方法过于昂贵和耗时。在这项研究中，我们的目标是发展一种诊断青少年NAFLD的方法，这将适用于对一般健康年轻人的大型研究。我们将测试3500名17岁英国人的血液测试结果以及与超声扫描诊断的NAFLD相关的总脂肪和腹部脂肪测量值。一旦我们开发出一种安全的诊断工具，我们将在一个来自澳大利亚的17岁的独立小组中再次进行测试，以确保它确实有效。该项目汇集了研究方法、肝脏医学、临床病理学和肝脏扫描方面的国际专家团队。我们的研究结果将使这一领域急需的研究取得进展。

The liver is the largest glandular organ in the body and is involved in a large number of the body?s normal functions. It produces the chemicals needed to breakdown fat in the circulation and produces cholesterol. It converts glucose (sugar) from the circulation to a form that can be stored and is responsible for maintaining a proper level of glucose in the circulation. It also makes a number of amino acids (the basic building blocks of proteins), stores key vitamins and minerals and filters harmful substances, such as alcohol, from the body. Until recently high levels of alcohol intake were seen as the major cause of liver disease in developed population. However, because of the recent obesity epidemic the most common cause of liver disease in the developed world now is caused by deposits of fat in the liver, so called non-alcoholic fatty liver disease (NALFD). Studies from America suggest that NAFLD starts to occur in adolescence with up to 15% of healthy adolescents in the US having NAFLD. In adults NAFLD can progress to cirrhosis and is also associated with increased risk of diabetes and cardiovascular disease. However, its causes and consequences in adolescents have not been extensively studied because of the difficulties of safely and accurately diagnosing this condition. The most accurate way to diagnose NAFLD is to take a sample (biopsy) from the liver and examine it under a microscope. However, this method is potentially dangerous and very costly and is not practical for large-scale research studies. A number of scanning methods, including ultrasound scan, are also useful for accurate diagnosis but these are too expensive and time consuming for large-scale studies. In this study we aim to develop a way of diagnosing NAFLD in adolescents that would be suitable for large studies of generally healthy young people. We will test a number of blood test results and measurements of total fat and abdominal fat in relation to NAFLD diagnosed by ultrasound scan in 3500 UK individuals aged 17 years. Once we have developed a safe diagnostic tool we will then test it again in an independent group of 17 year olds from Australia, in order to make sure it really is valid. This project brings together an international team of experts in research methods, liver medicine, clinical pathology and liver scanning. Our results will enable the much needed research in this area to progress.