Fundamental Development of In-vivo NMR Technology to Understand Environmental Stress

目前的环境政策主要基于死亡、迁移和生殖等极端终点，但很少提供关于亚致命影响、毒性机制或协同效应的信息。暴露在低水平污染物混合物中是常态，而不是例外，微妙的亚致命影响对动物、植物和人类群体来说可以说是更危险的，因为它们通常是在身体症状蔓延后才被发现的。医学领域最近发现，环境暴露是许多神经退行性疾病的主要原因，包括与重金属和农药有关，但确切的环境原因尚不清楚。 考虑到我们环境的复杂性，传统的自上而下的方法涉及识别所有污染物及其降解产物，然后在单个化合物的基础上评估毒性，这是极具挑战性的。相反，自下而上的方法关注生物体本身，并询问以下问题：人群是否有压力？导致压力的应激源/应激源是什么？哪些生化途径受到影响？核磁共振是现代研究中最有力的工具之一，可以在体内应用。因此，活着的有机体成为对环境做出实时反应的“终极生物传感器”，而核磁共振光谱仪则解释生化变化，在分子水平上提供解释亚致命毒性的信息。最终目标是了解和分类复杂介质(如工业废水、废水)和自然水环境中的多方面应激反应，以便有一天这些分子指纹可以用于识别土著生物环境应激的确切原因。反过来，了解影响环境和人类健康的最有问题的压力源对于改进监测、有针对性的补救、预防和政策至关重要。 水生新生儿和卵特别容易受到毒素的影响，如果受到影响，整个种群和生态系统都可能受到影响。然而，由于其敏感性较低，目前的核磁共振方法需要100‘S新生儿/卵子，这使得常规筛查变得不可行。在这项提议中，将发展微线圈核磁共振、微线圈阵列、新的靶向实验和应用，以将体内核磁共振扩展到单个水生新生儿和卵子。由于增加的信号和多个样本的多路复用能力，实验时间可以从几个月减少到小时/分钟。据我们所知，没有其他技术能在体内提供如此丰富的分子信息。这一点，再加上科学问题变得越来越复杂，生物相关性始终处于领先地位，显然，这里开发的高分辨率活体核磁共振方法将是下一代科学研究的关键。

Present environmental policies are based largely on apical endpoints such as death, movement and reproduction, but provide little information on sub-lethal impacts, toxic mechanisms or synergistic effects. Exposure to low-level contaminant mixtures is the norm rather than the exception, and subtle sub-lethal effects, are arguably more hazardous, to animal, plant and human populations, as they are often only detected, after physical symptoms become widespread. The medical field have recently identified environmental exposure as the predominant cause of many neurodegenerative diseases including links to heavy metals and pesticides, but the exact environmental causes are not yet known. A traditional top down approach, which involves identifying all contaminants, their degradation products, and then assessing toxicities on an individual compound basis is extremely challenging given the complexity of our environment. Conversely, a bottom-up approach focuses on the organisms themselves and asks questions such as; is a population stressed?; what are the stressor/stressors causing the stress?; and which biochemical pathways are impacted? Nuclear Magnetic Resonance (NMR) is one of the most powerful tools in modern research and can be applied in-vivo. As such the living organism becomes the “ultimate biosensor” responding in real-time to its environment, while the NMR spectrometer interprets the biochemical changes, providing information explaining sub-lethal toxicity at the molecular-level. The ultimate goal is to understand and categorize multifaceted stress responses in complex media (e.g. industrial effluent, waste water) and the natural aquatic environment, such that, one day, these molecular fingerprints can be used to identify the exact cause of environmental stress in native organisms. In turn, the knowledge as to the most problematic stressors impacting environmental and human health is essential to improving monitoring, targeted remediation, prevention and policies. Aquatic neonates and eggs are especially susceptible to toxins, and if compromised, entire populations and ecosystems can be impacted. However, due to its low sensitivity, current NMR approaches require 100's of neonates/eggs, making routine screening impractical. In this proposal, micro-coil NMR, micro-coil arrays, novel targeted experiments and applications will be developed to extend in-vivo NMR to single aquatic neonates and eggs. Due to the increased signal and ability to multiplex many samples, the experiment time can be reduced from months down to hrs/mins. To our knowledge no other techniques come close to providing such a wealth of molecular information in-vivo. This, along with the fact that scientific questions are becoming increasingly complex and biological relevance is always at the forefront, it is clear the high resolution in-vivo NMR methods developed here, will be key to the next generation of scientific research in general.