Abstract 2963: Dihydromyricetin is a senomorphic agent to promote therapeutic outcome of age-related conditions including cancer and Alzheimer's disease

Abstract Aging is characterized by a progressive decline of organ function and gradual rise of susceptibility to multiple chronic disorders, with cancer being a primary cause of human morbidity and mortality worldwide. Cellular senescence represents a state of permanent cell cycle arrest and contributes to chronological aging and age-related diseases including Alzheimer's disease (AD), mainly through development of a distinct secretome termed the senescence-associated secretory phenotype (SASP). By screening a natural medicinal agent library, we noticed Rattan tea extract (RTE) has a prominent antiaging potential, wherein dihydromyricetin (DMY), the most abundant natural flavonoid in RTE, played a central role in suppressing the SASP expression of senescent cells. DMY enhanced total antioxidant capacity (T-AOC), increased catalase (CAT) and glutathione peroxidase (GSH-Px) activity, upregulated the expression of HO-1, NQO1, nuclear Nrf2 and phospho-ERK (p-ERK), but decreased malondialdehyde (MDA) level in senescent cells. Furthermore, DMY regulates PI3K/Akt/mTOR signaling pathway, NLRP3 inflammasome formation, the NF-κB complex activity and ER stress-response, each responsible for a full spectrum SASP development. Transcriptomic profiling suggested that DMY can dampen the genome-wide upregulation of pro-inflammatory factors produced by senescent cells, resulting in abrogated progression of cancer malignancy including elevated proliferation, migration, invasion and chemoresistance. Importantly, combination of DMY with classic chemotherapy significantly enhanced therapeutic efficacy, causing remarkable tumor regression and extending posttreatment survival. Alzheimer's disease (AD) is marked by the presence of amyloid plaques, neurofibrillary tangles, damaged neuronal macromolecules and redox sensitive ions. We found that DMY restrains inflammatory injury in microglial cells, reduces their apoptosis and inflammation, and inhibits TLR4 and MD2 expression. Results of small molecule-protein docking and pull-down assays indicated that DMY binds MD2 to suppress the formation of TLR4 complex. In AD mice, DMY improved the cognitive disorder of animals, suppressed inflammatory injury in brain and reduced TLR4 expression. Together, DMY represents a valid natural candidate that has senomorphic activity and can be applied for treatment of malignancies or neurodegenerative disorders such as AD, pathologies that frequently arise in late life of humans. Citation Format: Qixia Xu, Zi Li, Zhirui Jiang, Judith Campisi, Yu Sun. Dihydromyricetin is a senomorphic agent to promote therapeutic outcome of age-related conditions including cancer and Alzheimer's disease [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2963.