Sport and Health Sciences, University of Exeter , United Kingdom.
University of Exeter Medical School , United Kingdom.
J Appl Physiol (1985). 2019 Jan 1;126(1):246-254. doi: 10.1152/japplphysiol.00804.2018. Epub 2018 Nov 29.
Flavonoid supplementation improves brachial artery flow-mediated dilation (FMD), but it is not known whether flavonoids protect against vascular dysfunction induced by ischemia-reperfusion (IR) injury and associated respiratory burst. In a randomized, double-blind, placebo-controlled, crossover study, we investigated whether 4 wk supplementation with freeze-dried Montmorency cherry (MC) attenuated suppression of FMD after IR induced by prolonged forearm occlusion. Twelve physically inactive overweight, middle-aged men (52.8 ± 5.8 yr, BMI: 28.1 ± 5.3 kg/m) consumed MC (235 mg/day anthocyanins) or placebo capsules for 4 wk, with supplementation blocks separated by 4 wk washout. Before and after each supplementation block, FMD responses and plasma nitrate and nitrite ([ ]) concentrations were measured at baseline and 15, 30, and 45 min after prolonged (20 min) forearm occlusion. FMD response was significantly depressed by the prolonged occlusion ( P < 0.001). After a 45-min reperfusion, FMD was restored to baseline levels after MC (ΔFMD presupplementation: -30.5 ± 8.4%, postsupplementation: -0.6 ± 9.5%) but not placebo supplementation (ΔFMD presupplementation: -11.6 ± 10.6, postsupplementation: -25.4 ± 4.0%; condition × supplement interaction: P = 0.038). Plasma [ ] decreased after prolonged occlusion but recovered faster after MC compared with placebo (Δ45 min to baseline; MC: presupplementation: -15.3 ± 9.6, postsupplementation: -6.2 ± 8.1; Placebo: presupplementation: -16.3 ± 5.9, postsupplementation: -27.7 ± 11.1 nmol/l; condition × supplement × time interaction: P = 0.033). Plasma peroxiredoxin concentration ([Prx2]) was significantly higher after MC (presupplementation: 22.8 ± 1.4, postsupplementation: 28.0 ± 2.4 ng/ml, P = 0.029) but not after placebo supplementation (presupplementation: 22.1 ± 2.2, postsupplementation: 23.7 ± 1.5 ng/ml). In conclusion, 4 wk MC supplementation enhanced recovery of endothelium-dependent vasodilatation after IR, in parallel with faster recovery of plasma [ ], suggesting NO dependency. These protective effects seem to be related to increased plasma [Prx2], presumably conferring protection against the respiratory burst during reperfusion. NEW & NOTEWORTHY This is the first study to demonstrate that 4 wk of Montmorency cherry powder supplementation exerted protective effects on endothelium-dependent vasodilation after transient ischemia-reperfusion injury in overweight, physically inactive, nonmedicated, hypertensive middle-aged men. These effects seem to be due to increased nitric oxide availability, as evidenced by higher plasma nitrite concentration and peak arterial diameter during the flow-mediated dilation measurement. This may be a consequence of increased concentration of peroxiredoxin and other antioxidant systems and, hence, reduced reactive oxygen species exposure.
类黄酮补充剂可以改善肱动脉血流介导的扩张（FMD），但目前尚不清楚类黄酮是否可以预防缺血再灌注（IR）损伤引起的血管功能障碍和相关的呼吸爆发。在一项随机、双盲、安慰剂对照、交叉研究中，我们研究了在长时间前臂闭塞引起的 IR 后，4 周补充冻干蒙莫朗西樱桃（MC）是否可以减轻 FMD 的抑制。12 名身体不活跃的超重中年男性（52.8±5.8 岁，BMI：28.1±5.3 kg/m）分别服用 MC（每天 235 毫克花青素）或安慰剂胶囊 4 周，洗脱期为 4 周。在每个补充周期前后，在长时间（20 分钟）前臂闭塞前、闭塞后 15、30 和 45 分钟测量 FMD 反应和血浆硝酸盐和亚硝酸盐（[ ]）浓度。长时间闭塞显著抑制 FMD 反应（P<0.001）。再灌注 45 分钟后，MC 补充后 FMD 恢复到基线水平（ΔFMD 预补充：-30.5±8.4%，后补充：-0.6±9.5%），但安慰剂补充后未恢复（ΔFMD 预补充：-11.6±10.6，后补充：-25.4±4.0%；条件×补充交互作用：P=0.038）。长时间闭塞后[ ]下降，但 MC 恢复速度快于安慰剂（45 分钟到基线的差值；MC：预补充：-15.3±9.6，后补充：-6.2±8.1；安慰剂：预补充：-16.3±5.9，后补充：-27.7±11.1 nmol/l；条件×补充×时间交互作用：P=0.033）。MC 补充后过氧化物酶 2（[Prx2]）浓度显著升高（预补充：22.8±1.4，后补充：28.0±2.4 ng/ml，P=0.029），但安慰剂补充后无明显变化（预补充：22.1±2.2，后补充：23.7±1.5 ng/ml）。总之，4 周的 MC 补充可增强 IR 后内皮依赖性血管扩张的恢复，同时恢复更快的血浆[ ]，表明与 NO 依赖性有关。这些保护作用似乎与增加的血浆[Prx2]有关，可能为再灌注期间的呼吸爆发提供保护。本研究首次表明，4 周的蒙莫朗西樱桃粉补充对超重、身体不活跃、未服药、高血压中年男性短暂性缺血再灌注损伤后的内皮依赖性血管舒张具有保护作用。这些作用似乎是由于一氧化氮可用性增加，如血流介导的扩张测量期间更高的血浆亚硝酸盐浓度和峰值动脉直径所证明的。这可能是由于过氧化物酶和其他抗氧化系统浓度增加以及由此导致的活性氧暴露减少所致。
