Computational design of new tacrine analogs: an in silico prediction of their cholinesterase inhibitory, antioxidant, and hepatotoxic activities

Recent advances in potential enzymes and their therapeutic inhibitors for the treatment of Alzheimer's disease

Alzheimer's disease (AD), a chronic neurodegenerative disease, is clinically characterized by loss of memory and learning ability among other neurological deficits. Amyloid plaques, hyperphosphorylated tau protein, and neurofibrillary tangles involve in AD etiology. Meanwhile, enzymes and their inhibitors have become the focus of research in AD treatment. In this review, the molecular mechanisms involved in the pathogenesis of AD were overviewed and various enzymes such as acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), β-secretase, γ-secretase, monoamine oxidase (MAO), and receptor of advanced glycation end products (RAGE) were highlighted as potential targets for AD treatment. Several hybrid molecules with essential substructures derived from various chemotypes have demonstrated desired pharmacological activity. It is envisioned that the development of new drugs that inhibit enzymes involved in AD is a future trend in the management of the disease.

Revealing the antioxidant properties of alkyl gallates: a novel approach through quantum chemical calculations and molecular docking

CONTEXT

This study investigates the antioxidant potential of alkyl gallates (C1-C10), focusing on the impact of alkyl chain length and solvent polarity on their antioxidant properties. Known for their biomedical relevance in mitigating oxidative stress, alkyl gallates' structure-activity relationships, particularly regarding chain length and environmental factors, still need to be explored. Key thermochemical parameters, including bond dissociation enthalpy (BDE), ionization potential (IP), proton affinity (PA), and electron transfer enthalpy (ETE), reveal that shorter alkyl chains (C1-C4) exhibit superior antioxidant activity. In contrast, longer chains (C5-C10) show reduced effectiveness due to steric hindrance and lower solubility in polar solvents. Molecular docking studies also demonstrated favorable binding interactions with vital biological targets, further reinforcing their antioxidant potential.

METHODS

Quantum chemical calculations were performed using Gaussian 16 with the B3LYP/6-311G(dp) basis set for geometry optimizations. Solvent effects were modeled using the integral equation formalism-polarized continuum model (IEF-PCM). Molecular docking studies were conducted using AutoDockTools 4.2, targeting Tyrosine Kinase Hck, Heme Oxygenase, and Human Serum Albumin to evaluate fundamental binding interactions. These computational methods provided insights into alkyl gallates' chemical reactivity and antioxidant efficiency, allowing for the rational design of more potent antioxidant compounds.

Comprehensive safety evaluation of a novel multitargeting compound XYY-CP1106: A candidate for Alzheimer's disease

Multitargeting has become a promising strategy for the development of anti-Alzheimer's disease (AD) drugs, considering the complexity of molecular mechanisms in AD pathology. In most pre-clinical studies, the effectiveness of these multi-targeted anti-AD drugs has been demonstrated but comprehensive safety assessments are lacking. Here, the safety evaluation of a novel multi-targeted candidate in AD (XYY-CP1106), characterized by its dual-property of iron chelation and monoamine oxidase B inhibition, was conducted by multifaceted analysis. Acute toxicity in mice was conducted to investigate the safety of oral administration and the maximum tolerated dose of the agent. In vitro Ames analysis, CHL chromosomal aberration analysis, and bone marrow micronucleus analysis were executed to evaluate the genotoxicity. A teratogenesis investigation in pregnant mice were meticulously performed to evaluate the teratogenesis of XYY-CP1106. Furthermore, a 90-day long-term toxicity analysis in rats was investigated to evaluate the cumulative toxicity after long-term administration. Strikingly, no toxic phenomena were found in all investigations, demonstrating relatively high safety profile of the candidate compound. The securing of safety heightened the translational significance of XYY-CP1106 as a novel multi-targeted anti-AD candidate, supporting the rationality of multitargeting strategy in the designs of smart anti-AD drugs.

Structural and vibrational characterization of di-hydrated hydrochloride tacrine combining DFT with SQMFF approach

This research is a continuation of previously reported article on anhydrous freebase, cationic and hydrochloride tacrine. Here, structures and properties of di-hydrated species of cholinesterase inhibitor tacrine have been studied in gas phase and aqueous solution by using B3LYP/6-311G* and wB97XD/6-311G* levels of theory. Both methods show strong changes in the positions of two water molecules and similar solvation energies (-192.52 kJ/mol with the B3LYP method and -191.95 kJ/mol with the other one). The B3LYP method predicts low gap values for the anhydrous (2.4572 eV) and di-hydrated (3.2708 eV) species of tacrine in gas phase than the wB97XD/6-311G* method (7.2300 eV). Hence, higher reactivities are expected for the di-hydrated species in both media. Atoms in molecules (AIM) calculations support the lower stability of di-hydrated species in solution in agreement with its higher reactivity in this medium. Complete assignments of 104 vibration modes expected for di-hydrated hydrochloride by using the scaled mechanical force field (SQMFF) methodology have been reported. Both methods predict different assignments and scaled force constants presenting higher values those calculated with the wB97XD/6-311G* method. The predicted IR, Raman and 1H NMR spectra with both methods show good correlations with the corresponding experimental ones, however, better concordances between the 13C NMR and UV spectra are observed with the wB97XD/6-311G* method.