Systemic oxidative-nitrosative-inflammatory stress during acute exercise in hypoxia; implications for microvascular oxygenation and aerobic capacity

	Systemic oxidative-nitrosative-inflammatory stress during acute exercise in hypoxia; implications for microvascular oxygenation and aerobic capacity
	Woodside, JDS; Gutowski, M; Fall, L; James, PE; McEneny, J; Young, IS; Ogoh, S; Bailey, DM
刊名	EXPERIMENTAL PHYSIOLOGY
	2014
卷号	99 期号:12 页码:1648-1662
通讯作者	Bailey, DM (reprint author), Univ South Wales, Fac Life Sci & Educ, Neurovasc Res Lab, Pontypridd CF37 4AT, M Glam, Wales.,damian.bailey@southwales.ac.uk
英文摘要	New Findings What is the central question of this study? Exercise performance is limited during hypoxia by a critical reduction in cerebral and skeletal tissue oxygenation. To what extent an elevation in systemic free radical accumulation contributes to microvascular deoxygenation and the corresponding reduction in maximal aerobic capacity remains unknown. What is the main finding and its importance? We show that altered free radical metabolism is not a limiting factor for exercise performance in hypoxia, providing important insight into the fundamental mechanisms involved in the control of vascular oxygen transport. Exercise performance in hypoxia may be limited by a critical reduction in cerebral and skeletal tissue oxygenation, although the underlying mechanisms remain unclear. We examined whether increased systemic free radical accumulation during hypoxia would be associated with elevated microvascular deoxygenation and reduced maximal aerobic capacity (V.O2 max ). Eleven healthy men were randomly assigned single-blind to an incremental semi-recumbent cycling test to determine V.O2 max in both normoxia (21% O-2) and hypoxia (12% O-2) separated by a week. Continuous-wave near-infrared spectroscopy was employed to monitor concentration changes in oxy- and deoxyhaemoglobin in the left vastus lateralis muscle and frontal cerebral cortex. Antecubital venous blood samples were obtained at rest and at V.O2 max to determine oxidative (ascorbate radical by electron paramagnetic resonance spectroscopy), nitrosative (nitric oxide metabolites by ozone-based chemiluminescence and 3-nitrotyrosine by enzyme-linked immunosorbent assay) and inflammatory stress biomarkers (soluble intercellular/vascular cell adhesion1 molecules by enzyme-linked immunosorbent assay). Hypoxia was associated with increased cerebral and muscle tissue deoxygenation and lower .O2 max (P<0.05 versus normoxia). Despite an exercise-induced increase in oxidative-nitrosative-inflammatory stress, hypoxia per se did not have an additive effect (P>0.05 versus normoxia). Consequently, we failed to observe correlations between any metabolic, haemodynamic and cardiorespiratory parameters (P>0.05). Collectively, these findings suggest that altered free radical metabolism cannot explain the elevated microvascular deoxygenation and corresponding lower .O2 max in hypoxia. Further research is required to determine whether free radicals when present in excess do indeed contribute to the premature termination of exercise in hypoxia.
学科主题	Physiology
类目[WOS]	Physiology
关键词[WOS]	ACUTE MOUNTAIN-SICKNESS ; DYNAMIC CEREBRAL AUTOREGULATION ; SKELETAL-MUSCLE ; FREE-RADICALS ; INCREMENTAL EXERCISE ; HIGH-ALTITUDE ; CELLULAR MECHANISMS ; LIPID-PEROXIDATION ; EXCHANGE KINETICS ; HYPOBARIC HYPOXIA
收录类别	SCI
语种	英语
WOS记录号	WOS:000345854200015
内容类型	期刊论文
版本	出版稿
源URL	[http://202.127.25.143/handle/331003/250]
专题	上海生化细胞研究所_上海生科院生化细胞研究所
推荐引用方式 GB/T 7714	Woodside, JDS,Gutowski, M,Fall, L,et al. Systemic oxidative-nitrosative-inflammatory stress during acute exercise in hypoxia; implications for microvascular oxygenation and aerobic capacity[J]. EXPERIMENTAL PHYSIOLOGY,2014,99(12):1648-1662.
APA	Woodside, JDS.,Gutowski, M.,Fall, L.,James, PE.,McEneny, J.,...&Bailey, DM.(2014).Systemic oxidative-nitrosative-inflammatory stress during acute exercise in hypoxia; implications for microvascular oxygenation and aerobic capacity.EXPERIMENTAL PHYSIOLOGY,99(12),1648-1662.
MLA	Woodside, JDS,et al."Systemic oxidative-nitrosative-inflammatory stress during acute exercise in hypoxia; implications for microvascular oxygenation and aerobic capacity".EXPERIMENTAL PHYSIOLOGY 99.12(2014):1648-1662.