Scientific Clinical Institutes Maugeri, IRCCS Lumezzane, Cardiac Rehabilitation Division, 25065 Lumezzane (Brescia), Italy.
Division of Human Anatomy and Physiopathology, Department of Clinical and Experimental Sciences, University of Brescia, Viale Europa, 11-25124 Brescia, Italy.
Nutrients. 2018 Mar 22;10(4):391. doi: 10.3390/nu10040391.
Proteins are macro-molecules crucial for cell life, which are made up of amino acids (AAs). In healthy people, protein synthesis and degradation are well balanced. However, in the presence of hypercatabolic stimulation (i.e., inflammation), protein breakdown increases as the resulting AAs are consumed for metabolic proposes. Indeed, AAs are biochemical totipotent molecules which, when deaminated, can be transformed into energy, lipids, carbohydrates, and/or biochemical intermediates of fundamental cycles, such as the Krebs' cycle. The biochemical consequence of hyper-catabolism is protein disarrangement, clinically evident with signs such as sarcopenia, hypalbuminemia, anaemia, infection, and altered fluid compartmentation, etc. Hypercatabolic protein disarrangement (HPD) is often underestimated by clinicians, despite correlating with increased mortality, hospitalization, and morbidity quite independent of the primary disease. Simple, cheap, repeatable measurements can be used to identify HPD. Therefore, identification and treatment of proteins' metabolic impairment with appropriate measurements and therapy is a clinical strategy that could improve the prognosis of patients with acute/chronic hypercatabolic inflammatory disease. Here, we describe the metabolism of protein and AAs in hypercatabolic syndrome, illustrating the clinical impact of protein disarrangement. We also illustrate simple, cheap, repeatable, and worldwide available measurements to identify these conditions. Finally, we provide scientific evidence for HPD nutritional treatment.
蛋白质是细胞生命所必需的大分子物质,由氨基酸(AAs)组成。在健康人群中,蛋白质的合成和降解处于平衡状态。然而,在存在过度分解代谢刺激(如炎症)的情况下,蛋白质分解增加,因为产生的氨基酸被用于代谢目的。事实上,氨基酸是生化全能分子,当脱氨基时,可以转化为能量、脂质、碳水化合物和/或基本循环的生化中间产物,如三羧酸循环。过度分解代谢的生化后果是蛋白质排列紊乱,临床上表现为肌肉减少症、低白蛋白血症、贫血、感染和体液分布改变等迹象。尽管高分解代谢性蛋白紊乱(HPD)与死亡率增加、住院和发病率增加密切相关,但临床医生往往低估了这种情况,而这些因素与原发性疾病无关。简单、廉价、可重复的测量方法可用于识别 HPD。因此,通过适当的测量和治疗来识别和治疗蛋白质代谢障碍是一种临床策略,可以改善急性/慢性高分解代谢炎症性疾病患者的预后。在这里,我们描述了过度分解代谢综合征中蛋白质和氨基酸的代谢,说明了蛋白质紊乱的临床影响。我们还介绍了简单、廉价、可重复和全球可用的测量方法来识别这些情况。最后,我们为 HPD 营养治疗提供了科学证据。