China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China.
Toxicology Centre, University of Saskatchewan, Saskatoon, SK, Canada.
Glob Chang Biol. 2021 Jul;27(14):3282-3298. doi: 10.1111/gcb.15638. Epub 2021 May 2.
Arctic warming associated with global climate change poses a significant threat to populations of wildlife in the Arctic. Since lipids play a vital role in adaptation of organisms to variations in temperature, high-resolution mass-spectrometry-based lipidomics can provide insights into adaptive responses of organisms to a warmer environment in the Arctic and help to illustrate potential novel roles of lipids in the process of thermal adaption. In this study, we studied an ecologically and economically important species-Arctic char (Salvelinus alpinus)-with a detailed multi-tissue analysis of the lipidome in response to chronic shifts in temperature using a validated lipidomics workflow. In addition, dynamic alterations in the hepatic lipidome during the time course of shifts in temperature were also characterized. Our results showed that early life stages of Arctic char were more susceptible to variations in temperature. One-year-old Arctic char responded to chronic increases in temperature with coordinated regulation of lipids, including headgroup-specific remodeling of acyl chains in glycerophospholipids (GP) and extensive alterations in composition of lipids in membranes, such as less lyso-GPs, and more ether-GPs and sphingomyelin. Glycerolipids (e.g., triacylglycerol, TG) also participated in adaptive responses of the lipidome of Arctic char. Eight-week-old Arctic char exhibited rapid adaptive alterations of the hepatic lipidome to stepwise decreases in temperature while showing blunted responses to gradual increases in temperature, implying an inability to adapt rapidly to warmer environments. Three common phosphatidylethanolamines (PEs) (PE 36:6|PE 16:1_20:5, PE 38:7|PE 16:1_22:6, and PE 40:7|PE 18:1_22:6) were finally identified as candidate lipid biomarkers for temperature shifts via machine learning approach. Overall, this work provides additional information to a better understanding of underlying regulatory mechanisms of the lipidome of Arctic organisms in the face of near-future warming.
北极变暖与全球气候变化相关，对北极地区的野生动物种群构成重大威胁。由于脂质在生物体适应温度变化方面起着至关重要的作用，基于高分辨率质谱的脂质组学可以深入了解生物体对北极变暖环境的适应反应，并有助于说明脂质在热适应过程中的潜在新作用。在这项研究中，我们研究了一种具有生态和经济重要性的物种——北极鳕鱼（Salvelinus alpinus），使用经过验证的脂质组学工作流程，对其进行了详细的多组织脂质组分析，以应对慢性温度变化。此外，还对温度变化过程中肝脏脂质组的动态变化进行了表征。我们的研究结果表明，北极鳕鱼的早期生命阶段更容易受到温度变化的影响。一年龄的北极鳕鱼对慢性温度升高的反应是通过脂质的协调调节来实现的，包括甘油磷酯（GP）中酰基链的特定头部基团重塑以及膜中脂质组成的广泛改变，例如更少的溶血甘油磷酯（lyso-GP）和更多的醚甘油磷酯（ether-GP）和神经鞘磷脂（sphingomyelin）。甘油酯（例如三酰基甘油，TG）也参与了北极鳕鱼脂质组的适应反应。八周龄的北极鳕鱼对温度的逐步降低表现出快速的适应改变，而对温度的逐渐升高则表现出迟钝的反应，这意味着它们无法快速适应温暖的环境。三种常见的磷脂酰乙醇胺（PE）（PE 36:6|PE 16:1_20:5、PE 38:7|PE 16:1_22:6 和 PE 40:7|PE 18:1_22:6）最终通过机器学习方法被确定为温度变化的候选脂质生物标志物。总的来说，这项工作为更好地理解未来北极生物脂质组在面对近未来变暖时的潜在调节机制提供了更多信息。
