长期头低位卧床休息前、期间和之后的营养状况评估。

Nutritional status assessment before, during, and after long-duration head-down bed rest.

作者信息

Zwart Sara R, Oliver Susan A Mathews, Fesperman J Vernell, Kala Geeta, Krauhs Jane, Ericson Karen, Smith Scott M

机构信息

Nutritional Biochemistry Laboratory, Human Adaptation and Countermeasures Division, NASA Johnson Space Center, Houston, TX 77058, USA.

出版信息

Aviat Space Environ Med. 2009 May;80(5 Suppl):A15-22. doi: 10.3357/asem.br07.2009.

DOI:10.3357/asem.br07.2009

PMID:19476165

Abstract

INTRODUCTION

Bed rest is a valuable ground-based model for many of the physiological changes that are associated with spaceflight. Nutritional changes during and after 60 or 90 d of head-down bed rest were evaluated.

METHODS

A total of 13 subjects (8 men, 5 women; ages 26-54 yr) participated in either 60 or 90 d of bed rest. Blood and urine were collected twice before bed rest and about once per month during bed rest. Samples were stored frozen and batch analyzed. Data were analyzed using repeated-measures analysis of variance.

RESULTS

During bed rest, markers of bone resorption (such as N-telopeptide excretion, P < 0.001) increased and serum concentration of parathyroid hormone decreased (P < 0.001). Also, oxidative damage markers such as superoxide dismutase increased (P < 0.05), and after 90 d of bed rest, total antioxidant capacity decreased (P < 0.05). During bed rest, iron status indices showed patterns of increased iron stores with a decreased concentration of transferrin receptors (P < 0.01).

DISCUSSION

These changes are similar to some of those observed during spaceflight, and further document the utility of bed rest as a model of spaceflight.

摘要

引言

卧床休息是一种重要的地面模型，可用于研究许多与太空飞行相关的生理变化。我们评估了60天或90天头低位卧床休息期间及之后的营养变化。

方法

共有13名受试者（8名男性，5名女性；年龄26 - 54岁）参与了60天或90天的卧床休息。在卧床休息前采集两次血液和尿液样本，卧床休息期间大约每月采集一次。样本冷冻保存并进行批量分析。数据采用重复测量方差分析。

结果

在卧床休息期间，骨吸收标志物（如N - 端肽排泄，P < 0.001）增加，甲状旁腺激素血清浓度降低（P < 0.001）。此外，氧化损伤标志物如超氧化物歧化酶增加（P < 0.05），卧床休息90天后，总抗氧化能力降低（P < 0.05）。在卧床休息期间，铁状态指标显示铁储存增加，转铁蛋白受体浓度降低（P < 0.01）。