在衰老过程中，许多组织和生物系统的功能逐渐下降，导致与年龄相关的疾病，如神经退行性、炎症性、代谢性、心血管疾病和癌症。在本综述中，我们重点关注与年龄相关的脑疾病，尤其是阿尔茨海默病和帕金森病的细胞老化和神经退化的分子基础，并介绍调节年龄相关分子功能失调的营养物质或植物化学物质，潜在地提供预防或治疗效益。根据目前的知识，神经胶质细胞基因失调和神经炎症、端粒衰减、神经干细胞退化、血管系统功能障碍、活性氧自由基、女性染色体X不活化丧失和肠道菌群失调在神经退行性疾病中发挥关键作用，相互影响。有几种植物化学物质（例如姜黄素、EGCG、富马酸、月桂黄素、花青素、白藜芦醇、植酸、乙酰染料、菜酸甾醇、水飞蓟素、白藜芦醇二硫化物和山楂酸）可以调节年龄增长的大脑中受影响的一个或多个关键基因（例如TREM2、C3、C3aR1、TNFA、NF-kb、TGFB1&2、SIRT1&6、HMGB1和STING）的功能失调。尽管植物化学物质在减缓年龄相关脑疾病进展方面显示出希望，但更多的研究以了解它们在临床前系统中的有效性，无论是单独应用还是以组合形式应用，都有助于设计人类神经退行性疾病管理的新营养策略。

During aging, several tissues and biological systems undergo a progressive decline in function, leading to age-associated diseases such as neurodegenerative, inflammatory, metabolic, and cardiovascular diseases and cancer. In this review, we focus on the molecular underpinning of senescence and neurodegeneration related to age-associated brain diseases, in particular, Alzheimer's and Parkinson's diseases, along with introducing nutrients or phytochemicals that modulate age-associated molecular dysfunctions, potentially offering preventive or therapeutic benefits. Based on current knowledge, the dysregulation of microglia genes and neuroinflammation, telomere attrition, neuronal stem cell degradation, vascular system dysfunction, reactive oxygen species, loss of chromosome X inactivation in females, and gut microbiome dysbiosis have been seen to play pivotal roles in neurodegeneration in an interactive manner. There are several phytochemicals (e.g., curcumin, EGCG, fucoidan, galangin, astin C, apigenin, resveratrol, phytic acid, acacetin, daucosterol, silibinin, sulforaphane, withaferin A, and betulinic acid) that modulate the dysfunction of one or several key genes (e.g., TREM2, C3, C3aR1, TNFA, NF-kb, TGFB1&2, SIRT1&6, HMGB1, and STING) affected in the aged brain. Although phytochemicals have shown promise in slowing down the progression of age-related brain diseases, more studies to identify their efficacy, alone or in combinations, in preclinical systems can help to design novel nutritional strategies for the management of neurodegenerative diseases in humans.