Selective Pseudo-irreversible Butyrylcholinesterase Inhibitors Transferring Antioxidant Moieties to the Enzyme Show Pronounced Neuroprotective Efficacy In Vitro and In Vivo in an Alzheimer’s Disease Mouse Model

Abstract

A series of multitarget-directed ligands (MTDLs) was designed by functionalizing a pseudo-irreversible butyrylcholinesterase (BChE) inhibitor. The obtained hybrids were investigated in vitro regarding their hBChE and hAChE inhibition, their enzyme kinetics, and their antioxidant physicochemical properties (DPPH, ORAC, metal chelating). In addition, in vitro assays were applied to investigate antioxidant effects using murine hippocampal HT22 cells and immunomodulatory effects on the murine microglial N9 cell line. The MTDLs retained their antioxidative properties compared to the parent antioxidant-moieties in vitro and the inhibition of hBChE was maintained in the submicromolar range. Representative compounds were tested in a pharmacological Alzheimer’s disease (AD) mouse model and demonstrated very high efficacy at doses as low as 0.1 mg/kg. The most promising compound was also tested in BChE–/– mice and showed reduced efficacy. In vivo neuroprotection by BChE inhibition can be effectively enhanced by incorporation of structurally diverse antioxidant moieties.

Discovery and In Vivo Proof of Concept of a Highly Potent Dual Inhibitor of Soluble Epoxide Hydrolase and Acetylcholinesterase for the Treatment of Alzheimer’s Disease

“… 38 This makes inhibition of BChE another activity of interest for AD treatment. 39 , 40 Like 6-chlorotacrine and huprine Y, all the hybrids showed submicromolar potencies toward human BChE (hBChE), with hybrid 12c standing out by its potency (IC 50 179 nM) 3-fold higher than that of the parent 6-chlorotacrine ( Table 1 ).…”

Novel benzimidazole-based pseudo-irreversible butyrylcholinesterase inhibitors with neuroprotective activity in an Alzheimer's disease mouse model

“…20,23,36,37 Decarbamylation was quantified by dilution experiments, as described before. 20,23,25,37,38 hBChE was incubated with an high amount of inhibitor to assure complete inhibition (<10% enzyme activity). After dilution of the enzyme solution, reversible inhibitors show immediate restoration of the enzyme activity, while pseudoirreversible inhibitors show slow recovery of enzyme activity over time.…”

“…19,23,24,39,40 BChE knockout experiments had already confirmed excellent suitability of the used experimental setup to validate the effect of BChEIs on Aβ 25-35 induced learning performances in mice. 38,41 Cognitive dysfunction was hereby induced by singular intracerebroventricular injection of neurotoxic Aβ 25-35 prior to treatment with compound 11d for seven days. The compound was solubilised in saline using 18% of DMSO, utilising the better solubility of inhibitor 11d when compared to parent compound 2, which had to be solubilised in 60% of DMSO in saline, and injected once daily intraperitoneally.…”

Blood–Brain Barrier Permeable and NO-Releasing Multifunctional Nanoparticles for Alzheimer’s Disease Treatment: Targeting NO/cGMP/CREB Signaling Pathways

“…Yield 25%. 13 (15). A solution of compound 14 (20.0 g, 10 mmol) and Et 3 N (1.3 g, 13 mmol) in anhydrous DCM (50 mL) was cooled at 0 °C using an ice bath and stirred.…”

“…However, owing to the complicated pathological features of AD, these drugs can only alleviate symptoms. Thus far, several hallmarks, including neurotransmitter system deficits, neurotoxicity induced by aggregated Aβ (A-Aβ), neurofibrillary tangles (NFT), oxidative stress, mitochondrial dysfunction, and neuroinflammation, have been gradually disclosed in the past few decades. − Moreover, these promoters for AD pathogenesis are inter-related and interact with one another. − Accordingly, a strategy based on the concept of multitarget-directed ligands (MTDLs) has become relevant; this strategy involves the insertion of more than one pharmacophore into a molecule or a system to form multifunctional molecules. − Therefore, novel anti-AD drugs developed on the basis of the comprehensive understanding of the pathogenesis of the disease are preferred over traditional single-target molecules.…”