Atractylenolide III Mitigates Alzheimer's Disease by Enhancing Autophagy via the YY1-TFEB Pathway

Autophagy dysregulation serves as a significant pathogenic factor in Alzheimer's disease (AD), with transcription factor EB (TFEB) acting as a pivotal transcription factor that governs the process of autophagy. Atractylenolide III (AT-III), a terpenoid compound found in medicinal Atractylodes macrocephala Koidz, is well-known for its role in antioxidant and anti-inflammatory activities. The purpose of this study is to explore the beneficial impact of AT-III on AD pathology and identify the mechanisms involved. C. elegans CL4176, SH-SY5Y APP_SWE, and APP/PS1 mice were used to investigate the efficacy and possible mechanism of AT-III on the treatment of AD. AT-III reduced amyloid protein (Aβ) deposition in C. elegans CL4176 heads, prolonged the paralysis time, and reduced Aβ levels in SH-SY5Y APP_SWE cells. AT-III improved the learning and memory ability of APP/PS1 mice and decreased the deposition of Aβ plaques. Transcriptomics and experimental validation showed that AT-III stimulated transcription and translation of autolysosome-associated genes. AT-III enhanced co-localization of LC3 and LAMP2 with Aβ in APP/PS1 mice. Meanwhile, AT-III increased TFEB transcriptional activity, mRNA, and protein levels in the nucleus. Furthermore, AT-III enhanced the expression of Yin Yang 1 (YY1) protein, an upstream regulator of TFEB, and led to the stimulation of autophagy and lysosome biogenesis both in vivo and in vitro. The observed effects were reversed upon silencing YY1. AT-III may regulate the YY1-TFEB pathway, thereby restoring autophagy flux disturbances and ameliorating AD-related pathological changes and cognitive decline. This study provides a promising lead compound for intervention in AD.