Research Paper Volume 17, Issue 3 pp 822—850

Differential senolytic inhibition of normal versus Aβ-associated cholinesterases: implications in aging and Alzheimer’s disease

Sultan Darvesh1,2, , Meghan K. Cash1, , Katrina Forrestall1, , Hillary Maillet1, , Dane Sands1, ,

  • 1 Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
  • 2 Department of Medicine (Geriatric Medicine and Neurology), Dalhousie University, Halifax, Nova Scotia B3H 2E1 Canada

Received: December 4, 2024       Accepted: March 13, 2025       Published: March 29, 2025      

https://doi.org/10.18632/aging.206227
How to Cite

Copyright: © 2025 Darvesh et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

Cellular senescence is a hallmark of aging and the age-related condition, Alzheimer’s disease (AD). How senescence contributes to cholinergic and neuropathologic changes in AD remains uncertain. Furthermore, little is known about the relationship between senescence and cholinesterases (ChEs). Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are important in neurotransmission, cell cycle regulation, and AD amyloid-β (Aβ) pathology. Senolytic agents have shown therapeutic promise in AD models. Therefore, we evaluated in vitro and in silico activity of senolytics, dasatinib (1), nintedanib (2), fisetin (3), quercetin (4), GW2580 (5), and nootropic, meclofenoxate hydrochloride (6), toward AChE and BChE. As ChEs associated with AD pathology have altered biochemical properties, we also evaluated agents 1-6 in AD brain tissues. Enzyme kinetics showed agents 1, 3, 4, and 6 inhibited both ChEs, while 2 and 5 inhibited only AChE. Histochemistry showed inhibition of Aβ plaque-associated ChEs (1 and 2: both ChEs; 5: BChE; 6: AChE), but not normal neural-associated ChEs. Modeling studies showed 1-6 interacted with the same five binding locations of both ChEs, some of which may be allosteric sites. These agents may exert their beneficial effects, in part, by inhibiting ChEs associated with AD pathology and provide new avenues for development of next-generation inhibitors targeting pathology-associated ChEs.

Abbreviations

Aβ: amyloid-β; ABP: acyl binding pocket; AChE: acetylcholinesterase; AD: Alzheimer’s disease; ATChI: acetylthiocholine iodide; BChE: butyrylcholinesterase; Bibfl120: nintedanib; BTChI: butyrylthiocholine iodide; CAIP: cholinergic anti-inflammatory pathway; CAS: catalytic active site; ChAT: choline acetyltransferase; ChE: cholinesterase; ChEI: cholinesterase inhibitor; DAB: 3,3’-diaminobenzidine tetrahydrochloride; dH2O: distilled water; DTNB: 5,5-dithio-bis-(2-nitrobenzoic acid); Ki: inhibition constant; H2O2: hydrogen peroxide; IL-1β: interleukin 1β; IL-6: interleukin 6; KR: Karnovsky-Roots; mAChR: muscarinic acetylcholine receptor; MOE: Molecular Operating Environment; nAChR: nicotinic acetylcholine receptor; OAH: oxyanion hole; PAS: peripheral anionic site; PB: phosphate buffer; PCS: π-cationic site; PDB: Protein Databank; SAMP8: senescence-accelerated prone 8 mouse; SASP: senescence-associated secretory phenotype; TNB: 5-thio-2-nitrobenzoic acid; TNFα: tumor necrosis factor α.