COMPUTER MODEL OF HUMAN SUBSTRATE METABOLISM

人体底物代谢的计算机模型

• 批准号: 6369874
• 负责人: JEAN-PIERRE FLATT
• 金额: $ 7.85万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-01 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6369874
• 关键词: bioenergetics; body composition; body physical activity; carbohydrate metabolism; computer program /software; computer simulation; diet; exercise; glucose metabolism; human data; information dissemination; mathematical model; metabolism; model design /development; nutrient intake activity; nutrition related tag

Variations in daily food intake are quite large in free- living individuals and not well synchronized with variations in energy expenditure (EE). Although this leads to substantial short term energy imbalances, long-term errors in the energy balance are generally remarkably small (e.g. less than the 2 percent of energy turnover over a year). Because changes in EE elicited by food intake attenuate only slightly the impact of over- or under-eating, weight maintenance depends primarily on appropriate adjustment of food intake of EE. The body's glycogen reserved are not much greater than the amount of carbohydrate (CHO) habitually consumed in one day. Evolution was therefore compelled to develop regulatory features giving especially high priority to the maintenance of CHO balance. An important issue in understanding body weight regulation, when access to food in unrestricted, is whether maintenance of stable glycogen reserves is achieved merely through adjustment of glucose oxidation to CHO intake, or whether this may be helped by influences induced by changing glycogen levels on food intake. However, given the loose control of daily energy intake and balance, it is difficult to establish whether this, and/or other mechanisms are involved in bringing about appropriate 'corrective changes' in food intake. To gain some insight about these difficulties, the development of a computer model of human energy metabolism was undertaken. It uses the Systems Dynamics approach in which changes in the content of various compartments are computed over consecutive time intervals. The course of events can be displayed in tables and graphs as a function of time, over hours, or hundreds of days. When conditions are kept constant, the simulations lead in time to steady-states; if aberrant configurations are reached, they suggest the changes which need to be implemented in the model to make it progressively more consistent with current knowledge of substrate metabolism in man. This grant application seeks funds to pursue the development of the a computer model constructed by integration of subsystems which themselves are models of substrate metabolism in the body's major organs. In time, a user-friendly interface will be developed enabling investigators, students, dieticians, nutritionists and others to have an interactive opportunity to obtain images of substrate metabolism in man and to observe its responses to conditions which can be specified and altered by the user.

在自由生活的个体中，每日食物摄入量的变化相当大，并且与能量消耗（EE）的变化不同步。 虽然这会导致大量的短期能量不平衡，但能量平衡的长期误差通常非常小（例如，一年中的能量周转率小于2%）。 由于食物摄入引起的EE变化仅轻微减弱过度或进食不足的影响，因此体重维持主要取决于适当调整EE的食物摄入量。身体的糖原储备量并不比一天中习惯消耗的碳水化合物（CHO）量大得多。 因此，进化被迫发展出特别优先考虑维持CHO平衡的调节功能。 了解体重调节的一个重要问题是，当不受限制地获得食物时，是否仅通过调节葡萄糖氧化至CHO摄入量来维持稳定的糖原储备，或者是否通过改变糖原水平对食物摄入量的影响来帮助。然而，由于对每日能量摄入和平衡的控制不严格，很难确定这一点和/或其他机制是否参与了食物摄入的适当“纠正变化”。为了深入了解这些困难，开发了人类能量代谢的计算机模型。 它使用系统动力学方法，在连续的时间间隔内计算各个隔室的内容变化。 事件的过程可以显示在表格和图形中，作为时间、小时或数百天的函数。 当条件保持不变时，模拟及时导致稳态;如果达到异常配置，他们提出了需要在模型中实施的改变，以使其逐渐与人类基质代谢的现有知识更加一致。本拨款申请寻求资金，以继续开发通过整合子系统构建的计算机模型，这些子系统本身就是基质模型。身体主要器官的新陈代谢。 届时，将开发一个用户友好的界面，使调查人员、学生、营养师、营养学家和其他人有一个互动的机会获得人体基质代谢的图像，并观察其对用户可以指定和改变的条件的反应。