Role of dietary protein and exercise on biomarkers of immune activation in older patients during hospitalization
- PDF / 639,582 Bytes
- 5 Pages / 595.276 x 790.866 pts Page_size
- 99 Downloads / 227 Views
SHORT COMMUNICATION
Role of dietary protein and exercise on biomarkers of immune activation in older patients during hospitalization Barbara Strasser1,3 · Gabriele Kohlboeck1 · Maria Hermanky2 · Michael Leitzmann3 Received: 12 December 2019 / Accepted: 18 December 2019 © Springer Nature Switzerland AG 2020
Abstract The aim of this study was to examine the effect of short-term protein supplementation (aiming to consume 1.2 g protein/kg body weight per day) combined with moderate resistance training on 3 days of the week on tryptophan–kynurenine metabolism in 40 older patients with hip fracture. Secondary outcomes for physical recovery were hand-grip strength and chair-rise score. Older patients with hip fracture exhibited higher degrees of immune activation, detected by increased neopterin and kynurenine to tryptophan levels compared with reference values for healthy elderly with no significant differences between those who received the exercise–protein intervention compared to the control. Increasing dietary protein intake during hospitalization did not alleviate the Th1-type immune response in the elderly patient. On the other hand, muscularity per se may affect immune activation responses following injury, as improvements in maximum hand-grip strength with the intervention were related to decreases in neopterin levels. Keywords Aging · Exercise · Dietary protein · Muscle disuse · Tryptophan–kynurenine metabolism
Introduction The process of ageing is accompanied by chronic immune activation, and sarcopenia may represent a consequence of a counter-regulatory strategy of the immune system. Thereby, inflammatory cytokines, in particular, Th1-type cytokine interferon-gamma (IFN-γ), induces various biochemical pathways such as tryptophan (Trp) breakdown. Tryptophan deprivation can suppress immune activation processes via restriction of protein biosynthesis and the induction of regulatory T-cells by kynurenine (Kyn) metabolites [1]. The mode of Trp degradation and concentration Electronic supplementary material The online version of this article (https://doi.org/10.1007/s40520-019-01461-7) contains supplementary material, which is available to authorized users. * Barbara Strasser [email protected] 1
Center for Gastrointestinal Diseases and Metabolism, Medical Faculty, Sigmund Freud Private University, Freudplatz 3, 1020 Vienna, Austria
2
AUVA Lorenz Boehler Trauma Unit, 1200 Vienna, Austria
3
Department of Epidemiology and Preventive Medicine, University Regensburg, 93053 Regensburg, Germany
of Kyn is a function of free Trp concentration, which is in turn influenced by competing amino acids such as leucine, which is a major regulator of muscle protein synthesis [2]. In parallel, IFN-γ also induces the production of neopterin in human monocyte-derived macrophages and dendritic cells, the elevation of which is often linked with conditions of immune activation and inflammation such as frailty [3]. Thus, the activated immune system in older individuals can be detected by increased neopt
Data Loading...
