Ross Mark, Ingram Lesley, Taylor Guy, Malone Eva, Simpson Richard J, West Dan, Florida-James Geraint
School of Applied Sciences, Edinburgh Napier University, Edinburgh, United Kingdom.
Institute of Cellular Medicine, Newcastle University, Newcastle, United Kingdom.
Physiol Rep. 2018 Jun;6(12):e13697. doi: 10.14814/phy2.13697.
Aging is associated with elevated cardiovascular disease risk. As a result of aging, endothelial dysfunction develops, partly due to a reduction in vascular regenerative ability. CD31 T cells (angiogenic T cells; T ) possess highly angiogenic capabilities; however, these cells are significantly reduced in older populations. In addition, older populations possess significantly higher senescent and highly differentiated T-cell levels in circulation, and these are reported to be highly exercise responsive. We investigated whether older adults display greater levels of circulating senescent (CD28 ) T cells and whether these cells were more exercise responsive than CD28 T cells. Young (18-25 years; n = 9) and older (60-75 years; n = 10) healthy men undertook a 30-min cycling bout at 70% V˙O peak, with circulating T cells (CD3 CD31 CD28 ; including CD4 and CD8 subsets) measured preexercise, postexercise, and 1 h post exercise by flow cytometry. Older adults displayed reduced basal levels of T cells (mean ± SEM: 410 ± 81 vs. 784 ± 118 cells·μL, P = 0.017), despite a greater proportion of these cells being CD28 (26.26 ± 5.08 vs. 13.36 ± 2.62%, P = 0.044). Exercise significantly increased the circulating number of T cells in both young and older men. However, in older men alone, exercise preferentially mobilized CD28 CD8 T cells compared with CD28 T cells (time × phenotype interaction: P = 0.022; Δ74 ± 29 vs. Δ27 ± 15 cells·μL, P = 0.059), with no such difference observed between these phenotypes in the young population. In conclusion, this is the first study to demonstrate that despite observing lower circulating numbers of T cells, older adults display greater levels of senescent T cells in comparison with younger individuals, and these cells are more exercise responsive than CD28 T cells. Lower number of circulating T and greater levels of senescent-associated CD28 T may contribute to greater CVD risk with advancing age.
衰老与心血管疾病风险升高相关。随着年龄增长，内皮功能障碍逐渐发展，部分原因是血管再生能力下降。CD31+ T细胞（血管生成性T细胞；T）具有高度血管生成能力；然而，这些细胞在老年人群中显著减少。此外，老年人群循环中衰老和高度分化的T细胞水平显著更高，据报道这些细胞对运动反应强烈。我们研究了老年人循环中衰老的（CD28-）T细胞水平是否更高，以及这些细胞是否比CD28+ T细胞对运动更敏感。年轻（18 - 25岁；n = 9）和年长（60 - 75岁；n = 10）的健康男性以70%的最大摄氧量进行了30分钟的骑行运动，在运动前、运动后和运动后1小时通过流式细胞术检测循环T细胞（CD3+ CD31+ CD28-；包括CD4和CD8亚群）。尽管老年人中这些细胞中CD28-的比例更高（26.26±5.08%对13.36±2.62%，P = 0.044），但老年人的T细胞基础水平较低（平均值±标准误：410±81对784±118个细胞·μL，P = 0.017）。运动显著增加了年轻和年长男性循环中T细胞的数量。然而，仅在老年男性中，与CD28+ T细胞相比，运动优先动员了CD28- CD8+ T细胞（时间×表型相互作用：P = 0.022；Δ74±29对Δ27±15个细胞·μL，P = 0.059），在年轻人群中这些表型之间未观察到此类差异。总之，这是第一项研究表明，尽管老年人循环中T细胞数量较少，但与年轻人相比，其衰老T细胞水平更高，且这些细胞比CD28+ T细胞对运动更敏感。循环T细胞数量减少和衰老相关的CD28- T细胞水平升高可能导致随着年龄增长心血管疾病风险增加。
