Excellence in Research of dietary blueberry delays aging and reverses aging-induced physical dysfunctions by regulating PPAR pathway

这项研究的目的是了解饮食中摄入蓝莓是如何起作用的，特别是对于65岁以上的人来说，蓝莓已被证明对健康有积极影响。通过小鼠实验，该项目将重点研究蓝莓在分子、细胞和组织层面的抗衰老机制。如果初步结果在计划中的小鼠长期实验中成立，那么这项研究可能会在人类身上开展工作，通过食用天然蓝莓产品来促进健康和延长寿命。通过研究影响肌肉和血管的分子途径的新实验，两个重要的观点将得到验证：(1)饮食中摄入蓝莓可以延长健康的寿命，甚至从老年开始；(2)饮食中摄入蓝莓可以延缓正常的衰老过程。除了了解某些类型的食物如何促进健康的明显社会效益外，该项目还将为一所历史悠久的黑人大学的少数民族学生（6名研究生和6名本科生）提供深入的研究培训。虽然衰老过程的确切机制尚不清楚，但延缓衰老引起的身体功能障碍和相关疾病的发展是促进健康衰老的必要和有效策略。PI最近报道，饮食中摄入表儿茶素（EC），一种包括蓝莓在内的各种食物中的生物活性成分，可以逆转衰老引起的骨骼肌（SkM）功能障碍，并提高老年小鼠的存活率。兔眼蓝莓在所有新鲜水果中含有最高的EC。该项目将验证膳食蓝莓EC通过调节老年小鼠PPAR/NF-kB通路逆转衰老诱导的SkM和血管内皮功能障碍的假设。两个主要目标构成了实验工作。目的1：在剂量依赖寿命方案中测试膳食蓝莓和EC的影响。将兔眼蓝莓（高EC）、高丛蓝莓（低EC）或纯EC冻干粉分别喂给20月龄C57BL/6小鼠（7组，公、母各30只/组），直至自然寿命结束。完整的Kaplan-Meier生存曲线和DNA甲基化时钟将用于监测衰老过程。目的2：验证PPAR/NF-kB通路介导蓝莓EC在骨骼肌和血管中的抗衰老作用。将含/不含PPAR特异性拮抗剂GW9662的兔眼蓝莓全粉饲喂20月龄小鼠15周，同时进行跑步机性能和离体试验。包括SkM、主动脉、血清和体外培养细胞在内的组织将通过转录组和代谢组分析来确定PPAR/NF-kB通路的作用和抗衰老作用的其他机制。作为一项关于饮食对生化途径影响的实验研究，本研究将有助于推进这类人类健康研究的方法，特别是建立蓝莓摄入延缓衰老引起的骨骼肌和血管功能障碍并延长人类寿命的机制。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This study aims to understand how the dietary intake of blueberries, which have been shown to have positive effects on health, might work to do so, particularly with regards to people over 65 years of age. Using mice, the project will focus on blueberry’s anti-aging mechanisms at the level of molecules, cells, and tissues. If the preliminary results hold true in the planned longer-term experiments on mice, then the research may lead to work in humans to promote health and extend lifespan by consuming natural blueberry products. With novel experiments examining molecular pathways that impact muscle and blood vessels, two important ideas will be tested: (1) dietary intake of blueberry can extend a healthy lifespan, even starting from advanced age, and (2) dietary intake of blueberry can delay the normal aging process. In addition to the clear societal benefits of understanding how some types of food work to promote health, this project will also provide in-depth research training to minority students (6 graduate students and 6 undergraduates) at a Historically Black University.While the exact mechanisms underlying the aging process are not well understood, delaying the aging-induced physical dysfunctions and related disease development is an essential and effective strategy to promote healthy aging. The PI recently reported that dietary intake of epicatechin (EC), a bioactive component of various foods, including blueberries, reversed aging-induced skeletal muscle (SkM) dysfunction and promoted the survival rate of aged mice. Rabbiteye blueberries contain the highest EC of all fresh fruits. The project will test the hypothesis that dietary blueberry EC reverses the aging-induced dysfunctions of SkM and vascular endothelium by regulating PPAR/NF-kB pathways in aged mice. Two primary objectives structure the experimental work. Objective 1: Test the effects of dietary blueberry and EC in a dose-dependent lifespan protocol. Freeze-dried powders of rabbiteye blueberry (high EC), highbush blueberry (low EC), or pure EC will be administrated to 20-month-old C57BL/6 mice (7 groups, 30 male, 30 female mice/group) until the natural end of lifespan. Complete Kaplan-Meier survival curves and DNA methylation clocks will be used to monitor the aging process. Objective 2: Test that PPAR/NF-kB pathways mediate blueberry EC anti-aging effect in skeletal muscle and vasculature. The whole powder of rabbiteye blueberry, pure EC with/out PPAR specific antagonist GW9662, will be fed to 20-month-old mice for 15 weeks while treadmill performance and ex vivo assays are conducted in parallel. Tissues including SkM, aorta, and serum and in vitro cultured cells will be used to determine the roles of PPAR/NF-kB pathways and other mechanisms of the anti-aging effect by conducting transcriptome and metabolome analyses. As an experimental study of the impact of diet on biochemical pathways, this study will help advance the methodologies for this type of human-health research, in general, and to establish, in particular, the mechanisms by which blueberry intake delays aging-induced dysfunction of skeletal muscle and vasculature and then extends the lifespan in humans.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.