Liggins Institute, University of Auckland , Grafton , New Zealand.
Department of Molecular and Integrative Physiology, University of Michigan , Ann Arbor, Michigan.
J Appl Physiol (1985). 2018 Aug 1;125(2):271-286. doi: 10.1152/japplphysiol.00169.2018. Epub 2018 Apr 26.
Strenuous exercise can result in skeletal muscle damage, leading to the systemic mobilization, activation, and intramuscular accumulation of blood leukocytes. Eicosanoid metabolites of arachidonic acid (ARA) are potent inflammatory mediators, but whether changes in dietary ARA intake influence exercise-induced inflammation is not known. This study investigated the effect of 4 wk of dietary supplementation with 1.5 g/day ARA ( n = 9, 24 ± 1.5 yr) or corn-soy oil placebo ( n = 10, 26 ± 1.3 yr) on systemic and intramuscular inflammatory responses to an acute bout of resistance exercise (8 sets each of leg press and extension at 80% one-repetition maximum) in previously trained men. Whole EDTA blood, serum, peripheral blood mononuclear cells (PMBCs), and skeletal muscle biopsies were collected before exercise, immediately postexercise, and at 2, 4, and 48 h of recovery. ARA supplementation resulted in higher exercise-stimulated serum creatine kinase activity [incremental area under the curve (iAUC) P = 0.046] and blood leukocyte counts (iAUC for total white cells, P < 0.001; neutrophils: P = 0.007; monocytes: P = 0.015). The exercise-induced fold change in peripheral blood mononuclear cell mRNA expression of interleukin-1β ( IL1B), CD11b ( ITGAM), and neutrophil elastase ( ELANE), as well as muscle mRNA expression of the chemokines interleukin-8 ( CXCL8) and monocyte chemoattractant protein 1 ( CCL2) was also greater in the ARA group than placebo. Despite this, ARA supplementation did not influence the histological presence of leukocytes within muscle, perceived muscle soreness, or the extent and duration of muscle force loss. These data show that ARA supplementation transiently increased the inflammatory response to acute resistance exercise but did not impair recovery. NEW & NOTEWORTHY Daily arachidonic acid supplementation for 4 wk in trained men augmented the acute systemic and intramuscular inflammatory response to a subsequent bout of resistance exercise. Greater exercise-induced inflammatory responses in men receiving arachidonic acid supplementation were not accompanied by increased symptoms of exercise-induced muscle damage. Although increased dietary arachidonic acid intake does not appear to influence basal inflammation in humans, the acute inflammatory response to exercise stress is transiently increased following arachidonic acid supplementation.
剧烈运动可导致骨骼肌损伤，导致全身血液白细胞动员、激活和在肌肉内蓄积。花生四烯酸（ARA）的类二十烷酸代谢物是强有力的炎症介质，但饮食中 ARA 摄入的变化是否影响运动引起的炎症尚不清楚。本研究旨在探讨补充 4 周 1.5 g/天 ARA（n = 9，24 ± 1.5 岁）或玉米油安慰剂（n = 10，26 ± 1.3 岁）对先前受过训练的男性单次抗阻运动（8 组，腿推和伸展，80%一次重复最大值）后全身和肌肉内炎症反应的影响。运动前、运动后即刻以及恢复 2、4 和 48 小时采集全 EDTA 血、血清、外周血单核细胞（PMBC）和骨骼肌活检。ARA 补充使运动后血清肌酸激酶活性升高（增量 AUC，P = 0.046）和白细胞计数增加（总白细胞的增量 AUC，P < 0.001；中性粒细胞：P = 0.007；单核细胞：P = 0.015）。外周血单核细胞白细胞介素 1β（IL1B）、CD11b（ITGAM）和中性粒细胞弹性蛋白酶（ELANE）mRNA 表达以及肌肉趋化因子白细胞介素 8（CXCL8）和单核细胞趋化蛋白 1（CCL2）mRNA 表达的运动诱导倍数变化在 ARA 组也高于安慰剂组。尽管如此，ARA 补充并未影响肌肉内白细胞的组织学存在、肌肉酸痛程度以及肌肉力量丧失的程度和持续时间。这些数据表明，ARA 补充剂可短暂增加急性抗阻运动后的全身和肌肉内炎症反应，但不会损害恢复。新的和值得注意的是，在训练有素的男性中补充每日花生四烯酸 4 周可增强随后进行的抗阻运动后的急性全身和肌肉内炎症反应。接受 ARA 补充的男性运动诱导的炎症反应增强并未伴有运动引起的肌肉损伤症状增加。尽管增加饮食中 ARA 摄入似乎不会影响人类的基础炎症，但 ARA 补充后，运动应激的急性炎症反应会短暂增加。
