From Chemical Discrepancy to Mechanistic Insight: UPLC‐MS, Bioinformatics, and In Vivo Studies on the Anti‐Brain Aging Effects of Polygalae Radix and Its Processed Products

The challenge of combating brain aging is significant due to its intricate pathogenesis. Polygalae radix (PT), a well-known herbal remedy derived from the dried root of Polygala tenuifolia Willd., serves as a traditional Chinese medicine and is also utilized in health foods. The primary processed products of PT are PT processed with licorice (PT + L) and PT processed with honey (PT + ER). Both PT and its processed products exhibit anti-brain aging properties, but their mechanisms remain unclear. This study investigated the brain-penetrating components and mechanisms of PT, PT + L, and PT + ER using UPLC-Q-TOF-MS, network pharmacology, molecular docking, and in vivo assays. Thirteen brain-penetrating components were identified, including tenuifolin, 3,4,5-trimethoxycinnamic acid, chlorogenic acid, liquiritigenin, and caffeic acid. Core targets (BDNF, Mfn1, Mfn2, Drp1, and Fis1) interacted with these components. In vivo, PT and its processed products improved memory, reduced hippocampal damage, regulated the HPA axis, and enhanced antioxidant capacity by modulating proteins involved in mitochondrial dynamics and BDNF. Processed products showed superior efficacy: PT + ER prominently regulated the HPA axis, while PT + L significantly upregulated BDNF. This study clarifies the material basis and multitarget mechanisms of PT and its processed variants, confirming traditional processing benefits and providing experimental evidence for clinical use in age-related neurodegenerative disorders.