Hull Bradford, Irby Isabella M, Miller Kayla M, Anderson Ally, Gardea Emily A, Sutphin George L
University of Arizona.
bioRxiv. 2024 Jan 9:2024.01.09.574889. doi: 10.1101/2024.01.09.574889.
Cellular stress is a fundamental component of age-associated disease. Cells encounter various forms of stress - oxidative stress, protein misfolding, DNA damage, etc. - and respond by activating specific, well-defined stress response pathways. As we age, the burden of stress and resulting damage increases while our cells' ability to deal with the consequences becomes diminished due to dysregulation of cellular stress response pathways. Many interventions that extend lifespan activate one or more stress response pathways or allow cells to maintain normal stress response later in life. The nematode is a commonly used model for both aging and stress response research. As such, stress response experiments are regularly conducted as part of studies focused on mechanisms of aging in . However, experimental design across experiments in the field are highly variable, including stressor dose, age at exposure, culture type (liquid vs. solid), bacterial strain used as a food source, and environmental temperature. These differences can result in different experimental outcomes, making comparison of results between studies challenging. Here we evaluate several experimental variables that are variable in the published literature and find that each can meaningfully alter experimental outcomes for multiple stressors. Our goal is to raise awareness of the issue of experimental variability within the field and suggest a standardized experimental design to serve as a set of guidelines for future experiments. By adopting these guidelines as a starting point, and explicitly noting differences in specific experiments, we aim to promote rigor and reproducibility, ultimately fostering more interpretable and translatable outcomes in geroscience research.
细胞应激是与年龄相关疾病的一个基本组成部分。细胞会遇到各种形式的应激——氧化应激、蛋白质错误折叠、DNA损伤等——并通过激活特定的、明确的应激反应途径做出反应。随着年龄的增长，应激负担和由此产生的损伤会增加，而由于细胞应激反应途径的失调，我们细胞应对后果的能力会减弱。许多延长寿命的干预措施会激活一种或多种应激反应途径，或者使细胞在生命后期维持正常的应激反应。线虫是衰老和应激反应研究中常用的模型。因此，应激反应实验经常作为关注线虫衰老机制研究的一部分进行。然而，该领域不同实验的实验设计差异很大，包括应激源剂量、暴露时的年龄、培养类型（液体与固体）、用作食物来源的细菌菌株以及环境温度。这些差异可能导致不同的实验结果，使得不同研究之间的结果比较具有挑战性。在这里，我们评估了已发表文献中存在差异的几个实验变量，发现每个变量都能显著改变多种应激源的实验结果。我们的目标是提高该领域对实验变异性问题的认识，并提出一种标准化的实验设计，作为未来实验的一套指导方针。通过将这些指导方针作为起点，并明确指出具体实验中的差异，我们旨在提高严谨性和可重复性，最终在老年科学研究中促进更具可解释性和可转化性的结果。
