We synthesized eleven new amiridine-piperazine hybrids 5a-j and 7 as potential multifunctional agents for Alzheimer's disease (AD) treatment by reacting N-chloroacetylamiridine with piperazines. The compounds displayed mixed-type reversible inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Conjugates were moderate inhibitors of equine and human BChE with negligible fluctuation in anti-BChE activity, whereas anti-AChE activity was substantially dependent on N4-substitution of the piperazine ring. Compounds with para-substituted aromatic moieties (5g, 5h, and bis-amiridine 7) had the highest anti-AChE activity in the low micromolar range. Top-ranked compound 5h, N-(2,3,5,6,7,8-hexahydro-1H-cyclopenta[b]quinolin-9-yl)-2-[4-(4-nitro-phenyl)-piperazin-1-yl]-acetamide, had an IC50 for AChE = 1.83 ± 0.03 μM (Ki = 1.50 ± 0.12 and αKi = 2.58 ± 0.23 μM). The conjugates possessed low activity against carboxylesterase, indicating a likely absence of unwanted drug-drug interactions in clinical use. In agreement with analysis of inhibition kinetics and molecular modeling studies, the lead compounds were found to bind effectively to the peripheral anionic site of AChE and displace propidium, indicating their potential to block AChE-induced β-amyloid aggregation. Similar propidium displacement activity was first shown for amiridine. Two compounds, 5c (R = cyclohexyl) and 5e (R = 2-MeO-Ph), exhibited appreciable antioxidant capability with Trolox equivalent antioxidant capacity values of 0.47 ± 0.03 and 0.39 ± 0.02, respectively. Molecular docking and molecular dynamics simulations provided insights into the structure-activity relationships for AChE and BChE inhibition, including the observation that inhibitory potencies and computed pKa values of hybrids were generally lower than those of the parent molecules. Predicted ADMET and physicochemical properties of conjugates indicated good CNS bioavailability and safety parameters comparable to those of amiridine and therefore acceptable for potential lead compounds at the early stages of anti-AD drug development.
- MeSH
- Acetylcholinesterase metabolism MeSH
- Alzheimer Disease drug therapy metabolism MeSH
- Aminoquinolines chemistry pharmacology MeSH
- Antioxidants chemical synthesis chemistry pharmacology MeSH
- Benzothiazoles antagonists & inhibitors MeSH
- Butyrylcholinesterase metabolism MeSH
- Cholinesterase Inhibitors chemical synthesis chemistry pharmacology MeSH
- Horses MeSH
- Sulfonic Acids antagonists & inhibitors MeSH
- Humans MeSH
- Models, Molecular MeSH
- Molecular Structure MeSH
- Neuroprotective Agents chemical synthesis chemistry pharmacology MeSH
- Oxidative Stress drug effects MeSH
- Piperazine chemistry pharmacology MeSH
- Dose-Response Relationship, Drug MeSH
- Structure-Activity Relationship MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
A series of tacrine - benzothiazole hybrids incorporate inhibitors of acetylcholinesterase (AChE), amyloid β (Aβ) aggregation and mitochondrial enzyme ABAD, whose interaction with Aβ leads to mitochondrial dysfunction, into a single molecule. In vitro, several of 25 final compounds exerted excellent anti-AChE properties and interesting capabilities to block Aβ aggregation. The best derivative of the series could be considered 10w that was found to be highly potent and selective towards AChE with the IC50 value in nanomolar range. Moreover, the same drug candidate exerted absolutely the best results of the series against ABAD, decreasing its activity by 23% at 100 μM concentration. Regarding the cytotoxicity profile of highlighted compound, it roughly matched that of its parent compound - 6-chlorotacrine. Finally, 10w was forwarded for in vivo scopolamine-induced amnesia experiment consisting of Morris Water Maze test, where it demonstrated mild procognitive effect. Taking into account all in vitro and in vivo data, highlighted derivative 10w could be considered as the lead structure worthy of further investigation.
- MeSH
- 3-Hydroxyacyl CoA Dehydrogenases antagonists & inhibitors metabolism MeSH
- Acetylcholinesterase metabolism MeSH
- Alzheimer Disease drug therapy metabolism MeSH
- Amyloid beta-Peptides antagonists & inhibitors metabolism MeSH
- Benzothiazoles chemistry pharmacology MeSH
- Cholinergic Agents chemical synthesis chemistry pharmacology MeSH
- Enzyme Inhibitors chemical synthesis chemistry pharmacology MeSH
- Humans MeSH
- Mitochondria drug effects metabolism MeSH
- Molecular Structure MeSH
- Neuroprotective Agents chemical synthesis chemistry pharmacology MeSH
- Protein Aggregates drug effects MeSH
- Tacrine chemistry pharmacology MeSH
- Dose-Response Relationship, Drug MeSH
- Structure-Activity Relationship MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
The authors report on the synthesis and biological evaluation of new compounds whose structure combines tacrine and indole moieties. Tacrine-indole heterodimers were designed to inhibit cholinesterases and β-amyloid formation, and to cross the blood-brain barrier. The most potent new acetylcholinesterase inhibitors were compounds 3c and 4d (IC50 = 25 and 39 nM, respectively). Compound 3c displayed considerably higher selectivity for acetylcholinesterase relative to human plasma butyrylcholinesterase in comparison to compound 4d (selectivity index: IC50 [butyrylcholinesterase]/IC50 [acetylcholinesterase] = 3 and 0.6, respectively). Furthermore, compound 3c inhibited β-amyloid-dependent amyloid nucleation in the yeast-based prion nucleation assay and displayed no dsDNA destabilizing interactions with DNA. Compounds 3c and 4d displayed a high probability of crossing the blood-brain barrier. The results support the potential of 3c for future development as a dual-acting therapeutic agent in the prevention and/or treatment of Alzheimer's disease.
- MeSH
- Acetylcholinesterase metabolism MeSH
- Alzheimer Disease drug therapy MeSH
- Amyloid beta-Peptides metabolism MeSH
- Cholinesterase Inhibitors chemistry pharmacology MeSH
- Molecular Targeted Therapy MeSH
- Dimerization MeSH
- DNA chemistry MeSH
- Blood-Brain Barrier MeSH
- Indoles chemistry pharmacology MeSH
- Inhibitory Concentration 50 MeSH
- Humans MeSH
- Ligands MeSH
- Neuroprotective Agents chemistry pharmacology MeSH
- Drug Evaluation, Preclinical MeSH
- Molecular Dynamics Simulation MeSH
- Molecular Docking Simulation MeSH
- Tacrine chemistry pharmacology MeSH
- Protein Binding MeSH
- Structure-Activity Relationship MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Research Support, N.I.H., Extramural MeSH
Glomerulonephritis (GN) encompasses a diverse group of immune-mediated diseases that damage the glomerular component of the nephron. While kidney biopsy remains the gold standard for diagnosis, it often fails to provide adequate insight into the underlying etiology of GN. Current classification systems have limited our understanding of the disease's pathophysiology and hinder the development of targeted therapies. Immunosuppressive treatments, such as glucocorticoids, calcineurin inhibitors, cyclophosphamide, and rituximab, remain the mainstay of therapy, though many patients fail to achieve remission or experience significant adverse effects. Moreover, the complex and multifactorial nature of GN pathogenesis calls for more refined therapeutic approaches. In recent years, multitarget therapies-combining different immunosuppressive agents targeting distinct immune pathways-have emerged as promising alternatives. Evidence suggests that multitarget therapy may offer superior outcomes compared to standard treatments. Despite early success, further studies are needed to optimize these regimens, reduce toxicity, and extend benefits to a broader range of GN patients. The development of personalized, biomarker-driven treatments, potentially leveraging innovative drug delivery systems and targeted biologics, holds promise for transforming GN care in the future.
- Publication type
- Journal Article MeSH
Since 2002, no clinical candidate against Alzheimer's disease has reached the market; hence, an effective therapy is urgently needed. We followed the so-called "multitarget directed ligand" approach and designed 36 novel tacrine-phenothiazine heterodimers which were in vitro evaluated for their anticholinesterase properties. The assessment of the structure-activity relationships of such derivatives highlighted compound 1dC as a potent and selective acetylcholinesterase inhibitor with IC50 = 8 nM and 1aA as a potent butyrylcholinesterase inhibitor with IC50 = 15 nM. Selected hybrids, namely, 1aC, 1bC, 1cC, 1dC, and 2dC, showed a significant inhibitory activity toward τ(306-336) peptide aggregation with percent inhibition ranging from 50.5 to 62.1%. Likewise, 1dC and 2dC exerted a remarkable ability to inhibit self-induced Aβ1-42 aggregation. Notwithstanding, in vitro studies displayed cytotoxicity toward HepG2 cells and cerebellar granule neurons; no pathophysiological abnormality was observed when 1dC was administered to mice at 14 mg/kg (i.p.). 1dC was also able to permeate to the CNS as shown by in vitro and in vivo models. The maximum brain concentration was close to the IC50 value for acetylcholinesterase inhibition with a relatively slow elimination half-time. 1dC showed an acceptable safety and good pharmacokinetic properties and a multifunctional biological profile.
- MeSH
- Acetylcholinesterase metabolism MeSH
- Alzheimer Disease * drug therapy MeSH
- Amyloid beta-Peptides MeSH
- Butyrylcholinesterase metabolism MeSH
- Cholinesterase Inhibitors pharmacology MeSH
- Phenothiazines pharmacology MeSH
- Mice MeSH
- Drug Design MeSH
- Tacrine * pharmacology MeSH
- Structure-Activity Relationship MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
We discovered a small series of hit compounds that show multitargeting activities against key targets in Alzheimer's disease (AD). The compounds were designed by combining the structural features of the anti-AD drug donepezil with clioquinol, which is able to chelate redox-active metals, thus decreasing metal-driven oxidative phenomena and β-amyloid (Aβ)-mediated neurotoxicity. The majority of the new hybrid compounds selectively target human butyrylcholinesterase at micromolar concentrations and effectively inhibit Aβ self-aggregation. In addition, compounds 5-chloro-7-((4-(2-methoxybenzyl)piperazin-1-yl)methyl)-8-hydroxyquinoline (1 b), 7-((4-(2-methoxybenzyl)piperazin-1-yl)methyl)-8-hydroxyquinoline (2 b), and 7-(((1-benzylpiperidin-4-yl)amino)methyl)-5-chloro-8-hydroxyquinoline (3 a) are able to chelate copper(II) and zinc(II) and exert antioxidant activity in vitro. Importantly, in the case of 2 b, the multitarget profile is accompanied by high predicted blood-brain barrier permeability, low cytotoxicity in T67 cells, and acceptable toxicity in HUVEC primary cells.
- MeSH
- Alzheimer Disease drug therapy MeSH
- Amyloid beta-Peptides antagonists & inhibitors metabolism MeSH
- Antioxidants chemistry therapeutic use toxicity MeSH
- Butyrylcholinesterase chemistry metabolism MeSH
- Chelating Agents chemistry MeSH
- Cholinesterase Inhibitors chemistry therapeutic use toxicity MeSH
- Human Umbilical Vein Endothelial Cells MeSH
- Blood-Brain Barrier metabolism MeSH
- Indans chemistry therapeutic use toxicity MeSH
- Clioquinol chemistry therapeutic use toxicity MeSH
- Humans MeSH
- Copper chemistry MeSH
- Cell Line, Tumor MeSH
- Oxyquinoline chemistry therapeutic use toxicity MeSH
- Piperidines chemistry therapeutic use toxicity MeSH
- Drug Design MeSH
- Cell Survival drug effects MeSH
- Structure-Activity Relationship MeSH
- Zinc chemistry MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Alzheimer's disease (AD) is a major public health problem, which is due to its increasing prevalence and lack of effective therapy or diagnostics. The complexity of the AD pathomechanism requires complex treatment, e.g. multifunctional ligands targeting both the causes and symptoms of the disease. Here, we present new multitarget-directed ligands combining pharmacophore fragments that provide a blockade of serotonin 5-HT6 receptors, acetyl/butyrylcholinesterase inhibition, and amyloid β antiaggregation activity. Compound 12 has displayed balanced activity as an antagonist of 5-HT6 receptors ( Ki = 18 nM) and noncompetitive inhibitor of cholinesterases (IC50 hAChE = 14 nM, IC50 eqBuChE = 22 nM). In further in vitro studies, compound 12 has shown amyloid β antiaggregation activity (IC50 = 1.27 μM) and ability to permeate through the blood-brain barrier. The presented findings may provide an excellent starting point for further studies and facilitate efforts to develop new effective anti-AD therapy.
- MeSH
- Alzheimer Disease drug therapy etiology MeSH
- Amyloid beta-Peptides metabolism MeSH
- Butyrylcholinesterase pharmacology MeSH
- Cholinesterase Inhibitors pharmacology MeSH
- Humans MeSH
- Ligands * MeSH
- Models, Molecular MeSH
- Peptide Fragments metabolism MeSH
- Drug Design MeSH
- Molecular Docking Simulation MeSH
- Structure-Activity Relationship MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
