ABSTRACT
Novel hybrids N-(4-phenoxybenzyl)aniline were designed, synthesized, and evaluated for their potential AChE inhibitory activity along with antioxidant potential. The inhibitory potential (IC50) of synthesized analogs was evaluated against human cholinesterases (hAChE and hBChE) using Ellman's method. Among all the tested compounds, 42 with trimethoxybenzene substituent showed maximum hAChE inhibition with the competitive type of enzyme inhibition (IC50â¯=â¯1.32⯵M; Kiâ¯=â¯0.879⯵M). Further, parallel artificial membrane permeation assay (PAMPA-BBB) showed favorable BBB permeability by most of the synthesized compounds. Meanwhile, compound 42 also inhibited AChE-induced Aß aggregation (39.5-66.9%) in thioflavin T assay. The in vivo behavioral studies showed dose-dependent improvement in learning and memory by compound 42. The ex vivo studies also affirmed the significant AChE inhibition and antioxidant potential of compound 42 in brain homogenates.
Subject(s)
Acetylcholinesterase/chemical synthesis , Alzheimer Disease/drug therapy , Amyloid beta-Peptides/antagonists & inhibitors , Drug Design , Humans , Oxidative StressABSTRACT
In recent years, the use of acetylcholinesterases (AChEs) in biosensor technology has gained enormous attention, in particular with respect to insecticide detection. The principle of biosensors using AChE as a biological recognition element is based on the inhibition of the enzyme's natural catalytic activity by the agent that is to be detected. The advanced understanding of the structure-function-relationship of AChEs serves as the basis for developing enzyme variants, which, compared to the wild type, show an increased inhibition efficiency at low insecticide concentrations and thus a higher sensitivity. This review describes different expression systems that have been used for the production of recombinant AChE. In addition, approaches to purify recombinant AChEs to a degree that is suitable for analytical applications will be elucidated as well as the various attempts that have been undertaken to increase the sensitivity of AChE to specified organophosphates and carbamates using side-directed mutagenesis and employing the enzyme in different assay formats.
Subject(s)
Acetylcholinesterase/chemical synthesis , Acetylcholinesterase/metabolism , Biosensing Techniques/instrumentation , Cholinesterase Inhibitors/analysis , Protein Engineering/methods , Acetylcholinesterase/chemistry , Acetylcholinesterase/genetics , Biosensing Techniques/methods , Cholinesterase Inhibitors/chemistry , Enzymes, Immobilized/chemical synthesis , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/genetics , Enzymes, Immobilized/metabolism , Equipment Design , Gene Expression Regulation , Insecticides/analysis , Organophosphorus Compounds , Recombinant Proteins/chemical synthesis , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolismABSTRACT
The methanolysis of choline p-nitrophenylcarbonate in chloroform containing 1% methanol is catalyzed with turnover by ditopic receptors 1 and 2, consisting of a calix[6]arene connected to a bicyclic guanidinium by means of a short spacer. The calix[6]arene subunit strongly binds to the trimethylammonium head group through cation-pi interactions, whereas the guanidinium moiety is deputed to stabilize through hydrogen bonding reinforced by electrostatic attraction the anionic tetrahedral intermediate resulting from methoxide addition to the ester carbonyl. The observed cholinesterase activity had been anticipated on the basis of the ability of the ditopic receptors 1 and 2 to bind strongly to the choline phosphate DOPC, which is a transition state analogue for the BAc2-type cleavage of choline esters.
