小分子，大作为：酮体D-β羟基丁酸在医疗领域的应用与展望

Applications and perspectives of ketone body D-β-hydroxybutyrate in the medical fields

摘要:

人体两大供能模式主要是通过碳水化合物代谢或脂肪代谢。日常饮食下，身体会优先选择葡萄糖作为主要的能量来源。但近年来，科学家们发现在限制碳水化合物供给的条件下可以促进机体的脂肪代谢，该饮食模式可能会成为一种改善人类健康的全新的方式。其中，间歇性进食、生酮饮食等受到了广泛的关注，特别是在运动减肥、代谢疾病、脑部健康以及预防心血管疾病方面的效果十分明显。脂肪代谢中最为关键的产物是D-β-羟基丁酸(酮体，D3HB)，是组成微生物内聚物聚-D-β-羟基丁酸(PHB)的单体。D3HB是一个能够在不同细胞与组织器官中起到供能与保护作用的小分子物质。然而，仅靠饮食促发的营养性酮症会带来一定的副作用且需要经过非常长的适应期(3个月以上)，因此，外源性D3HB酮体的补充逐渐成为一种更加新颖、便捷的方式，用于帮助人体快速进入营养性酮症并激发相应的功能作用。文中详细阐述了人体产生D3HB的过程与其代谢路径、D3HB在人体内的作用效果以及外源性D3HB酮体在近年来的应用研究进展。

Abstract:

Human body can obtain energy from either carbohydrate or fat digestion.Although glucose metabolism derived from carbohydrate-based diets has long been utilized for energy supply,it has been recently discovered that shifting from glucose to fatty acid metabolism may become a novel way for improving human health especially when carbohydrate is deprived.In recent years,intermittent fasting and ketogenic diets have received a lot of attention in respect to favoring fatty acid metabolism.In all cases,fatty acid metabolism produces D-β-hydroxybutyrate (D3HB),which is a natural ketone body,as well as,a monomer of microbial poly-D-β-hydroxybutyrate (PHB).D3HB can be utilized by different cells of the body as an alternative energy fuel or an intracellular signaling molecule with multiple downstream signaling pathways.Usually,the serum level of D3HB is increased during ketogenic diets,however,requires a very long period of adaptation (over 3-months) and exhibits unwanted adverse effects.Hence,exogenous ketone supplements using D3HB have become a more effective approach to induce and maintain nutritional ketosis for subsequent functional effects.This review describes how D3HB is produced and metabolized within the body,the functional roles played by D3HB,and a detailed summary of the different applications of exogenous ketones that have been explored to date in both nutritional and therapeutical context.