COMPUTER MODEL OF HUMAN SUBSTRATE METABOLISM

人体底物代谢的计算机模型

• 批准号: 6517687
• 负责人: JEAN-PIERRE FLATT
• 金额: $ 3.98万
• 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 2004-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6517687
• 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.

自由生活的个体每日食物摄入量的变化相当大，并且与能量消耗（EE）的变化不太同步。 尽管这会导致严重的短期能源失衡，但能源平衡的长期误差通常非常小（例如，小于一年能源周转率的 2%）。 由于食物摄入引起的 EE 变化仅略微减弱饮食过量或不足的影响，因此体重维持主要取决于对 EE 食物摄入量的适当调整。身体储备的糖原并不比一天习惯性消耗的碳水化合物（CHO）多多少。 因此，进化被迫发展调控特征，特别高度重视维持 CHO 平衡。 在不受限制地获取食物时，了解体重调节的一个重要问题是，维持稳定的糖原储备是否仅通过调整葡萄糖氧化与 CHO 摄入量来实现，或者这是否可以通过改变食物中糖原水平引起的影响来实现摄入量。然而，由于对每日能量摄入和平衡的控制松散，很难确定这种机制和/或其他机制是否涉及在食物摄入中带来适当的“纠正性变化”。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内容物的变化。 事件的进程可以以表格和图表的形式显示为时间、几小时或数百天的函数。 当条件保持恒定时，模拟会及时达到稳态；如果达到异常配置，他们建议需要在模型中进行更改，以使其逐渐与人类底物代谢的当前知识更加一致。该拨款申请寻求资金来开发通过集成子系统构建的计算机模型，这些子系统本身就是人体主要器官中底物代谢的模型。 随着时间的推移，将开发出一个用户友好的界面，使研究人员、学生、营养师、营养师和其他人能够有一个互动的机会来获取人体底物代谢的图像，并观察其对用户指定和改变的条件的反应。