Calton Emily K, Keane Kevin N, Raizel Raquel, Rowlands Jordan, Soares Mario J, Newsholme Philip
School of Public Health, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Perth, Western Australia, 6845, Australia.
School of Biomedical Sciences, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Perth, Western Australia, 6845, Australia.
Redox Biol. 2017 Aug;12:814-820. doi: 10.1016/j.redox.2017.04.009. Epub 2017 Apr 13.
Vitamin D status [25(OH)D] has recently been reported to be associated with altered cellular bioenergetic profiles of peripheral blood mononuclear cells (PBMCs). No study has tracked the seasonal variation of 25(OH)D and its putative influence on whole body energy metabolism, cellular bioenergetic profiles, inflammatory markers and clinical chemistry.
Whole body energy metabolism and substrate utilisation were measured by indirect calorimetry. PBMCs obtained from the same subjects were isolated from whole blood, counted and freshly seeded. Bioenergetic analysis (mitochondrial stress test and glycolysis stress test) was performed using the Seahorse XF96 flux analyser. 25(OH)D was assessed using the Architect immunoassay method.
25(OH)D increased by a median (IQR) of 14.40 (20.13)nmol/L (p<0.001) from winter to summer and was accompanied by significant improvements in indices of insulin sensitivity, McAuley's index (p=0.019) and quantitative insulin sensitivity check index (p=0.028). PBMC mitochondrial parameters basal respiration, non-mitochondrial respiration, ATP production, proton leak, and maximal respiration decreased in summer compared to winter. Similarly, PBMC glycolytic parameters glycolytic activity, glucose response, and glycolytic capacity were all reduced in summer compared to winter. There was also a trend for absolute resting metabolic rate (RMR) to decrease (p=0.066). Markers of systemic inflammation MCP-1, IL-6, IL-8, IL-10, and IL-12p70 decreased significantly in summer compared to winter. Participants who entered winter with a low 25(OH)D (<50nmol/L), had the greatest alteration in bioenergetic parameters in summer, relative to those with winter 25(OH)D concentrations of 50-75nmol/L or >75nmol/L. The absolute change in 25(OH)D was not associated with altered bioenergetics.
Seasonal improvements in 25(OH)D was associated with reduced systemic inflammation, PBMC bioenergetic profiles and whole body energy metabolism. These observational changes in PBMC bioenergetics were most pronounced in those who had insufficient 25(OH)D in winter. The data warrants confirmation through cause and effect study designs.
最近有报道称维生素D状态[25(OH)D]与外周血单个核细胞（PBMC）的细胞生物能量谱改变有关。尚无研究追踪25(OH)D的季节性变化及其对全身能量代谢、细胞生物能量谱、炎症标志物和临床化学的假定影响。
通过间接测热法测量全身能量代谢和底物利用情况。从同一受试者的全血中分离出PBMC，进行计数并新鲜接种。使用海马XF96通量分析仪进行生物能量分析（线粒体应激试验和糖酵解应激试验）。采用Architect免疫分析方法评估25(OH)D。
从冬季到夏季，25(OH)D中位数（四分位间距）增加了14.40（20.13）nmol/L（p<0.001），同时胰岛素敏感性指标、麦考利指数（p=0.019）和定量胰岛素敏感性检查指数（p=0.028）有显著改善。与冬季相比，夏季PBMC线粒体参数基础呼吸、非线粒体呼吸、ATP产生、质子泄漏和最大呼吸均降低。同样，与冬季相比，夏季PBMC糖酵解参数糖酵解活性、葡萄糖反应和糖酵解能力均降低。绝对静息代谢率（RMR）也有下降趋势（p=0.066）。与冬季相比，夏季全身炎症标志物MCP-1、IL-6、IL-8、IL-10和IL-12p70显著降低。与冬季25(OH)D浓度为50-75nmol/L或>75nmol/L的参与者相比，冬季25(OH)D水平低（<50nmol/L）的参与者在夏季生物能量参数变化最大。25(OH)D的绝对变化与生物能量学改变无关。
25(OH)D的季节性改善与全身炎症减轻、PBMC生物能量谱和全身能量代谢降低有关。PBMC生物能量学的这些观察到的变化在冬季25(OH)D不足的人群中最为明显。这些数据需要通过因果研究设计来证实。
