RESUMEN
Cross-linking mass spectrometry (XL-MS) is emerging as a method at the crossroads of structural and cellular biology, uniquely capable of identifying protein-protein interactions with residue-level resolution and on the proteome-wide scale. With the development of cross-linkers that can form linkages inside cells and easily cleave during fragmentation on the mass spectrometer (MS-cleavable cross-links), it has become increasingly facile to identify contacts between any two proteins in complex samples, including in live cells or tissues. Photo-cross-linkers possess the advantages of high temporal resolution and high reactivity, thereby engaging all residue-types (rather than just lysine); nevertheless, photo-cross-linkers have not enjoyed widespread use and are yet to be employed for proteome-wide studies because their products are challenging to identify. Here, we demonstrate the synthesis and application of two heterobifunctional photo-cross-linkers that feature diazirines and N-hydroxy-succinimidyl carbamate groups, the latter of which unveil doubly fissile MS-cleavable linkages upon acyl transfer to protein targets. Moreover, these cross-linkers demonstrate high water-solubility and cell-permeability. Using these compounds, we demonstrate the feasibility of proteome-wide photo-cross-linking in cellulo. These studies elucidate a small portion of Escherichia coli's interaction network, albeit with residue-level resolution. With further optimization, these methods will enable the detection of protein quinary interaction networks in their native environment at residue-level resolution, and we expect that they will prove useful toward the effort to explore the molecular sociology of the cell.
Asunto(s)
Lisina , Proteoma , Proteoma/química , Espectrometría de Masas/métodos , Mapas de Interacción de Proteínas , Reactivos de Enlaces Cruzados/químicaRESUMEN
The cholinesterases are essential targets implicated in the pathogenesis of Alzheimer's disease (AD). In the present study, virtual screening and molecular docking are performed to identify the potential hits. Docking-post processing (DPP) and pose filtration protocols against AChE and BChE resulted in three hits (AW00308, HTS04089, and JFD03947). Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) and molecular dynamics simulation analysis affirmed the stability and binding pattern of the docked complex JFD03947, which was further synthesized and evaluated for in vitro cholinesterase inhibition (AChE, IC50 = 0.062 µM; BChE, IC50 = 1.482 µM) activity. The enzyme kinetics study of the JFD03947 against hAChE and hBChE suggested a mixed type of inhibition. The results of thioflavin T-assay also elicited anti-Aß aggregation activity by JFD03947. Further, biological evaluation of identified compound JFD03947 also showed neuroprotective ability against the SH-SY5Y neuroblastoma cell lines.
Asunto(s)
Acetilcolinesterasa/química , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/antagonistas & inhibidores , Butirilcolinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Biología Computacional/métodos , Diseño de Fármacos , Dominio Catalítico , Inhibidores de la Colinesterasa/química , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Agregado de ProteínasRESUMEN
Multitarget molecular hybrids of N-benzyl pyrrolidine derivatives were designed, synthesized, and biologically evaluated for the treatment of Alzheimer's disease (AD). Among the synthesized compounds, 4k and 4o showed balanced enzyme inhibitions against cholinesterases (AChE and BChE) and BACE-1. Both leads showed considerable PAS-AChE binding capability, excellent brain permeation, potential disassembly of Aß aggregates, and neuroprotective activity against Aß-induced stress. Compounds 4k and 4o also ameliorated cognitive dysfunction against the scopolamine-induced amnesia model in the Y-maze test. The ex vivo study signified attenuated brain AChE activity and antioxidant potential of compounds 4k and 4o. Furthermore, compound 4o also showed improvement in Aß-induced cognitive dysfunction by the Morris water maze test with excellent oral absorption characteristics ascertained by the pharmacokinetic study. In silico molecular docking and dynamics simulation studies of leads suggested their consensual binding affinity toward PAS-AChE in addition to aspartate dyad of BACE-1.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/farmacología , Diseño de Fármacos , Fármacos Neuroprotectores/farmacología , Pirrolidinas/farmacología , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/metabolismo , Amnesia/inducido químicamente , Amnesia/tratamiento farmacológico , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Animales , Butirilcolinesterasa/metabolismo , Línea Celular Tumoral , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Modelos Moleculares , Estructura Molecular , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/química , Pirrolidinas/síntesis química , Pirrolidinas/química , Ratas , Ratas Wistar , Escopolamina , Relación Estructura-ActividadRESUMEN
Thirty ferulic acid-based 1,3,4-oxadiazole molecular hybrids were designed, synthesized, and screened them for multifunctional inhibitory potential against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and beta-secretase-1 (BACE-1). Compound 6j was the most potent inhibitor of AChE (IC50 = 0.068 µM). It also showed equipotent inhibition of BChE and BACE-1 with IC50 values of 0.218 µM and 0.255 µM, respectively. Compound 6k possessed the most significant inhibition of BChE and BACE-1 with IC50 values, 0.163 µM and 0.211 µM, respectively. Compounds 6j and 6k elicited significant displacement of propidium iodide from PAS-AChE, excellent BBB permeability in PAMPA assay, and anti-Aß aggregatory activity in self- and AChE-induced experiments with neuroprotective activity towards neuroblastoma SH-SY5Y cells. The in vivo behavioral studies suggested amelioration of cognitive dysfunction by 6j and 6k in the Y maze test. The ex vivo study signified brain AChE inhibition and antioxidant activity from these compounds. Moreover, 6j showed improvement in learning and memory behavior in the Aß-induced ICV rat model by Morris water maze test with excellent oral absorption characteristics ascertained by pharmacokinetic studies.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/farmacología , Ácidos Cumáricos/farmacología , Diseño de Fármacos , Fármacos Neuroprotectores/farmacología , Oxadiazoles/farmacología , Acetilcolinesterasa/metabolismo , Administración Oral , Enfermedad de Alzheimer/metabolismo , Amnesia/inducido químicamente , Amnesia/tratamiento farmacológico , Amnesia/metabolismo , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Animales , Butirilcolinesterasa/metabolismo , Línea Celular Tumoral , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Ácidos Cumáricos/síntesis química , Ácidos Cumáricos/química , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Simulación del Acoplamiento Molecular , Estructura Molecular , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/química , Oxadiazoles/química , Agregado de Proteínas/efectos de los fármacos , Ratas , Ratas Wistar , Escopolamina , Relación Estructura-ActividadRESUMEN
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.
Asunto(s)
Acetilcolinesterasa/síntesis química , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/antagonistas & inhibidores , Diseño de Fármacos , Humanos , Estrés OxidativoRESUMEN
Novel hybrids bearing a 2-aminopyrimidine (2-AP) moiety linked to substituted 1,3,4-oxadiazoles were designed, synthesized and biologically evaluated. Among the developed compounds, 28 noncompetitively inhibited human acetylcholinesterase (hAChE; pIC50â¯=â¯6.52; Kiâ¯=â¯0.17⯵M) and showed potential in vitro antioxidant activity (60.0%) when evaluated using the Ellman's and DPPH assays, respectively. Compound 28 competitively displaced propidium iodide (PI) from the peripheral anionic site (PAS) of hAChE (17.6%) and showed high blood-brain barrier (BBB) permeability, as observed in the PAMPA-BBB assay. Additionally, compound 28 inhibited hAChE-induced Aß aggregation in a concentration-dependent manner according to the thioflavin T assay and was devoid of neurotoxic liability towards SH-SY5Y cell lines, as demonstrated by the MTT assay. The behavioral studies of compound 28 in mice showed a significant reversal of scopolamine-induced amnesia, as observed in Y-maze and passive avoidance tests. Furthermore, compound 28 exhibited significant AChE inhibition in the brain in ex vivo studies. An evaluation of oxidative stress biomarkers revealed the antioxidant potential of 28. Moreover, in silico molecular docking and dynamics simulation studies were used as a computational tool to evaluate the interactions of compound 28 with the active site residues of hAChE.
Asunto(s)
Inhibidores de la Colinesterasa/farmacología , Disfunción Cognitiva/tratamiento farmacológico , Diseño de Fármacos , Oxadiazoles/farmacología , Pirimidinas/farmacología , Acetilcolinesterasa/metabolismo , Animales , Butirilcolinesterasa/metabolismo , Línea Celular , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Disfunción Cognitiva/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Ratones , Modelos Moleculares , Estructura Molecular , Oxadiazoles/síntesis química , Oxadiazoles/química , Pirimidinas/síntesis química , Pirimidinas/química , Relación Estructura-ActividadRESUMEN
The novel hybrids bearing 4-aminopyridine (4-AP) tethered with substituted 1,3,4-oxadiazole nucleus were designed, synthesized, and evaluated for their potential AChE inhibitory property along with significant antioxidant potential. The inhibitory potential (IC50) of synthesized analogs was evaluated against human cholinesterases (hAChE and hBChE) using Ellman's method. Among all the compounds, 9 with 4-hydroxyl substituent showed maximum hAChE inhibition with the non-competitive type of enzyme inhibition (IC50â¯=â¯1.098⯵M; Kiâ¯=â¯0.960⯵M). Further, parallel artificial membrane permeation assay (PAMPA-BBB) showed significant BBB permeability in most of the synthesized compounds. Meanwhile, compound 9 also inhibited AChE-induced Aß aggregation (38.2-65.9%) by thioflavin T assay. The in vivo behavioral studies showed dose-dependent improvement in learning and memory by compound 9. The ex vivo studies also affirmed the significant AChE inhibition and antioxidant potential of compound 9 in brain homogenates.
Asunto(s)
Acetilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/farmacología , Disfunción Cognitiva/tratamiento farmacológico , Desarrollo de Medicamentos , Oxadiazoles/farmacología , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Animales , Reacción de Prevención/efectos de los fármacos , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/administración & dosificación , Inhibidores de la Colinesterasa/síntesis química , Disfunción Cognitiva/inducido químicamente , Relación Dosis-Respuesta a Droga , Electrophorus , Caballos , Humanos , Masculino , Memoria/efectos de los fármacos , Ratones , Estructura Molecular , Oxadiazoles/administración & dosificación , Oxadiazoles/síntesis química , Fragmentos de Péptidos/antagonistas & inhibidores , Fragmentos de Péptidos/metabolismo , Agregado de Proteínas/efectos de los fármacos , Escopolamina/administración & dosificación , Relación Estructura-ActividadRESUMEN
A series of novel piperazine tethered biphenyl-3-oxo-1,2,4-triazine derivatives were designed, and synthesized. Amongst the synthesized analogs, compound 6g showed significant non-competitive inhibitory potential against acetylcholinesterase (AChE, IC50; 0.2⯱â¯0.01⯵M) compared to standard donepezil (AChE, IC50: 0.1⯱â¯0.002⯵M). Compound 6g also exhibited significant displacement of propidium iodide from the peripheral anionic site (PAS) of AChE (22.22⯱â¯1.11%) and showed good CNS permeability in PAMPA-BBB assay (Pe(exp), 6.93⯱â¯0.46). The in vivo behavioral studies of compound 6g indicated significant improvement in cognitive dysfunctions against scopolamine-induced amnesia mouse models. Further, ex vivo studies showed a significant AChE inhibition and reversal of the scopolamine-induced oxidative stress by compound 6g. Moreover, molecular docking and dynamics simulations of compound 6g showed a consensual binding affinity and active site interactions with the PAS and active catalytic site (CAS) residues of AChE.
Asunto(s)
Inhibidores de la Colinesterasa/farmacología , Aprendizaje/efectos de los fármacos , Memoria/efectos de los fármacos , Nootrópicos/farmacología , Piperazinas/farmacología , Triazinas/farmacología , Acetilcolinesterasa/química , Acetilcolinesterasa/metabolismo , Animales , Antioxidantes/síntesis química , Antioxidantes/metabolismo , Antioxidantes/farmacología , Compuestos de Bifenilo/síntesis química , Compuestos de Bifenilo/metabolismo , Compuestos de Bifenilo/farmacología , Dominio Catalítico , Línea Celular Tumoral , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/metabolismo , Diseño de Fármacos , Humanos , Masculino , Ratones , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Nootrópicos/síntesis química , Nootrópicos/metabolismo , Piperazinas/síntesis química , Piperazinas/metabolismo , Unión Proteica , Torpedo , Triazinas/síntesis química , Triazinas/metabolismoRESUMEN
Based on the quantitative structure-activity relationship (QSAR), some novel p-aminobenzoic acid derivatives as promising cholinesterase enzyme inhibitors were designed, synthesized, characterized and evaluated to enhance learning and memory. The in vitro enzyme kinetic study of the synthesized compounds revealed the type of inhibition on the respective acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. The in vivo studies of the synthesized compounds exhibited significant reversal of cognitive deficits in the animal models of amnesia as compared to standard drug donepezil. Further, the ex vivo studies in the specific brain regions like the hippocampus, hypothalamus, and prefrontal cortex regions also exhibited AChE inhibition comparable to standard donepezil. The in silico molecular docking and dynamics simulations studies of the most potent compound 22 revealed the consensual interactions at the active site pocket of the AChE.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/uso terapéutico , Nootrópicos/uso terapéutico , para-Aminobenzoatos/uso terapéutico , Acetilcolinesterasa/química , Acetilcolinesterasa/metabolismo , Animales , Encéfalo/metabolismo , Butirilcolinesterasa/química , Butirilcolinesterasa/metabolismo , Dominio Catalítico , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/toxicidad , Diseño de Fármacos , Femenino , Cinética , Masculino , Memoria/efectos de los fármacos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Nootrópicos/síntesis química , Nootrópicos/química , Nootrópicos/toxicidad , Relación Estructura-Actividad Cuantitativa , Ratas , Semicarbazonas/síntesis química , Semicarbazonas/química , Semicarbazonas/uso terapéutico , Semicarbazonas/toxicidad , para-Aminobenzoatos/síntesis química , para-Aminobenzoatos/química , para-Aminobenzoatos/toxicidadRESUMEN
A series of novel hybrids comprising of 1,3,4-oxadiazole/thiadiazole and 1,2,4-triazole tethered to 5,6-diphenyl-1,2,4-triazin-3(2H)-one were designed, synthesised and evaluated as COX-2 inhibitors for the treatment of inflammation. The synthesised hybrids were characterised using FT-IR, 1H NMR, 13C NMR, elemental (C,H,N) analyses and assessed for their anti-inflammatory potential by in vitro albumin denaturation assay. Compounds exhibiting activity comparable to indomethacin and celecoxib were further evaluated for in vivo anti-inflammatory activity. Oral administration of promising compounds 3c-3e and 4c-4e did not evoke significant gastric, hepatic and renal toxicity in rats. These potential compounds exhibited reduced malondialdehyde (MDA) content on the gastric mucosa suggesting their protective effects by inhibition of lipid peroxidation. Based on the outcome of in vitro COX assay, compounds 3c-3e and 4c-4e (IC50 0.60-1.11µM) elicited an interesting profile as competitive selective COX-2 inhibitors. Further, selected compounds 3e and 4c were found devoid of cardiotoxicity post evaluation on myocardial infarcted rats. The in silico binding mode of the potential compounds into the COX-2 active site through docking and molecular dynamics exemplified their consensual interaction and subsequent COX-2 inhibition with significant implications for structure-based drug design.
Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Inhibidores de la Ciclooxigenasa 2/farmacología , Ciclooxigenasa 2/metabolismo , Diseño de Fármacos , Edema/tratamiento farmacológico , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Triazinas/farmacología , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Carragenina , Inhibidores de la Ciclooxigenasa 2/síntesis química , Inhibidores de la Ciclooxigenasa 2/química , Relación Dosis-Respuesta a Droga , Edema/inducido químicamente , Femenino , Compuestos Heterocíclicos de 4 o más Anillos/química , Humanos , Masculino , Ratones , Modelos Moleculares , Estructura Molecular , Ratas , Ratas Wistar , Relación Estructura-Actividad , Triazinas/síntesis química , Triazinas/química , Úlcera/inducido químicamente , Úlcera/tratamiento farmacológicoRESUMEN
Histone deacetylases (HDACs) are critical epigenetic drug targets that have gained significant attention in the scientific community for the treatment of cancer. The currently marketed HDAC inhibitors lack selectivity for the various HDAC isoenzymes. Here, we describe our protocol for the discovery of novel potential hydroxamic acid based HDAC3 inhibitors through pharmacophore modeling, virtual screening, docking, molecular dynamics (MD) simulation and toxicity studies. The ten pharmacophore hypotheses were established, and their reliability was validated by different ROC (receiving operator curve) analysis. Among them, the best model (Hypothesis 9 or RRRA) was employed for searching SCHEMBL, ZINC and MolPort database to screen out hit molecules as selective HDAC3 inhibitors, followed by different docking stages. MD simulation (50 ns) and MMGBSA study were performed to study the stability of ligand binding modes and with the help of trajectory analysis, to calculate the ligand-receptor complex RMSD (root-mean-square deviation), RMSF (root-mean-square fluctuation) and H-bond distance, etc. Finally, in-silico toxicity studies were performed on top screened molecules and compared with reference drug SAHA and established structure-activity relationship (SAR). The results indicated that compound 31, with high inhibitory potency and less toxicity (probability value 0.418), is suitable for further experimental analysis.Communicated by Ramaswamy H. Sarma.
Pharmacophore modeling and virtual screening were performed with hydroxamic acid derivatives as HDAC3 inhibitors.MD simulation was performed for 50 ns time duration for selected protein-ligand complexes.SAR and toxicity studies (using TOPKAT tool) were performed.The results of these studies might be valuable in the further design and development of more potent HDAC3 inhibitors.
Asunto(s)
Diseño de Fármacos , Ácidos Hidroxámicos , Simulación del Acoplamiento Molecular , Ligandos , Ácidos Hidroxámicos/farmacología , Reproducibilidad de los Resultados , Simulación de Dinámica Molecular , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/química , Relación Estructura-Actividad CuantitativaRESUMEN
THE OBJECTIVE OF WORK WAS TO FORMULATE, EVALUATE AND COMPARE THE TRANSDERMAL POTENTIAL OF NOVEL VESICULAR NANOCARRIERS: ethosomes and ultradeformable liposomes, containing clotrimazole (CLT), an anti-fungal bioactive. The ethosomal formulation (ET4) and ultradeformable liposomal (UL) formulation (TT3) showed highest entrapment 68.73 ± 1.4% and 55.51 ± 1.7%, optimal nanometric size range 132 ± 9.5 nm and 121 ± 9.7 nm, and smallest polydispersity index 0.027 ± 0.011 and 0.067 ± 0.009, respectively. The formulation ET4 provided enhanced transdermal flux 56.25 ± 5.49 µg/cm(2)/h and decreased the lag time of 0.9 h in comparison to TT3 formulation (50.16 ± 3.84 µg/cm(2)/h; 1.0 h). Skin interaction and FT-IR studies revealed greater penetration enhancing effect of ET4 than TT3 formulation. ET4 formulation also had the highest zone of inhibition (34.6 ± 0.57 mm), in contrast to TT3 formulation (29.6 ± 0.57 mm) and marketed cream formulation (19.0 ± 1.00 mm) against candidal species. Results suggested ethosomes to be the most proficient carrier system for dermal and transdermal delivery of clotrimazole.
RESUMEN
Alzheimer's disease (AD) is an enormous healthcare challenge, and 50 million people are currently suffering from it. There are several pathophysiological mechanisms involved, but cholinesterase inhibitors remained the major target from the last 2-3 decades. Among four available therapeutics (donepezil, rivastigmine, galantamine, and memantine), three of them are cholinesterase inhibitors. Herein, we describe the role of acetylcholine sterase (AChE) and related hypothesis in AD along with the pharmacological and chemical aspects of the available cholinesterase inhibitors. This chapter discusses the development of several congeners and hybrids of available cholinesterase inhibitors along with their binding patterns in enzyme active sites.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Inhibidores de la Colinesterasa/farmacología , Colinesterasas/metabolismo , Acetilcolina/metabolismo , Donepezilo/farmacología , Desarrollo de Medicamentos/métodos , Galantamina/farmacología , Humanos , Memantina/farmacología , Rivastigmina/farmacologíaRESUMEN
AD is a progressive neurodegenerative disorder and a leading cause of dementia in an aging population worldwide. The enormous challenge which AD possesses to global healthcare makes it as urgent as ever for the researchers to develop innovative treatment strategies to fight this disease. An in-depth analysis of the extensive available data associated with the AD is needed for a more comprehensive understanding of underlying molecular mechanisms and pathophysiological pathways associated with the onset and progression of the AD. The currently understood pathological and biochemical manifestations include cholinergic, Aß, tau, excitotoxicity, oxidative stress, ApoE, CREB signaling pathways, insulin resistance, etc. However, these hypotheses have been criticized with several conflicting reports for their involvement in the disease progression. Several issues need to be addressed such as benefits to cost ratio with cholinesterase therapy, the dilemma of AChE selectivity over BChE, BBB permeability of peptidic BACE-1 inhibitors, hurdles related to the implementation of vaccination and immunization therapy, and clinical failure of candidates related to newly available targets. The present review provides an insight to the different molecular mechanisms involved in the development and progression of the AD and potential therapeutic strategies, enlightening perceptions into structural information of conventional and novel targets along with the successful applications of computational approaches for the design of target-specific inhibitors.
Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Enfermedad de Alzheimer/metabolismo , Animales , HumanosRESUMEN
Multitargeted hybrids of N-benzylpiperidine and substituted 5-phenyl-1,3,4-oxadiazoles were designed, synthesized, and evaluated against Alzheimer's disease (AD). Tested compounds exhibited moderate to excellent inhibition against human acetylcholinesterase (hAChE), butyrylcholinesterase (hBChE), and beta-secretase-1 (hBACE-1). The potential leads 6g and 10f exhibited balanced inhibitory profiles against all the targets, with a substantial displacement of propidium iodide from the peripheral anionic site of hAChE. Hybrids 6g and 10f also elicited favorable permeation across the blood-brain barrier and were devoid of neurotoxic liability toward SH-SY5Y neuroblastoma cells. Both leads remarkably disassembled Aß aggregation in thioflavin T-based self- and AChE-induced experiments. Compounds 6g and 10f ameliorated scopolamine-induced cognitive dysfunctions in the Y-maze test. The ex vivo studies of rat brain homogenates established the reduced AChE levels and antioxidant activity of both compounds. Compound 6g also elicited noteworthy improvement in Aß-induced cognitive dysfunctions in the Morris water maze test with downregulation in the expression of Aß and BACE-1 proteins corroborated by Western blot and immunohistochemical analysis. The pharmacokinetic study showed excellent oral absorption characteristics of compound 6g. The in silico molecular docking and dynamics simulation studies of lead compounds affirmed their consensual binding interactions with PAS-AChE and aspartate dyad of BACE-1.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Oxadiazoles/uso terapéutico , Piperidinas/uso terapéutico , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/metabolismo , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Ácido Aspártico Endopeptidasas/metabolismo , Encéfalo/metabolismo , Diseño de Fármacos , Simulación del Acoplamiento Molecular , Oxadiazoles/farmacología , Piperidinas/farmacología , Ratas , Relación Estructura-ActividadRESUMEN
The multitarget-directed strategy offers an effective and promising paradigm to treat the complex neurodegenerative disorder, such as Alzheimer's disease (AD). Herein, a series of N-benzylpiperidine analogs (17-31 and 32-46) were designed and synthesized as multi-functional inhibitors of acetylcholinesterase (AChE) and ß-secretase-1 (BACE-1) with moderate to excellent inhibitory activities. Among the tested inhibitors, 25, 26, 40, and 41 presented the most significant and balanced inhibition against both the targets. Compounds 40 and 41 exhibited high brain permeability in the PAMPA-BBB assay, significant displacement of propidium iodide from the peripheral anionic site (PAS) of AChE, and were devoid of neurotoxicity towards SH-SY5Y neuroblastoma cell lines up to the maximum tested concentration of 80⯵M. Meanwhile, both these compounds inhibited self- and AChE-induced Aß aggregation in thioflavin T assay, which was also re-affirmed by morphological characterization of Aß aggregates using atomic force microscopy (AFM). Moreover, 40 and 41 ameliorated the scopolamine-induced cognitive impairment in elevated plus and Y-maze experiments. Ex vivo and biochemical analysis established the brain AChE inhibitory potential and antioxidant properties of these compounds. Further, improvement in Aß1-42-induced cognitive impairment was also observed by compound 41 in the Morris water maze experiment with significant oral absorption characteristics ascertained by the pharmacokinetic studies.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Inhibidores de la Colinesterasa/síntesis química , Diseño de Fármacos , Piperidinas/farmacología , Enfermedad de Alzheimer/enzimología , Enfermedad de Alzheimer/psicología , Animales , Barrera Hematoencefálica/metabolismo , Línea Celular Tumoral , Inhibidores de la Colinesterasa/farmacología , Disfunción Cognitiva , Humanos , Ratones , Piperidinas/síntesis química , Agregación Patológica de Proteínas/tratamiento farmacológico , Relación Estructura-ActividadRESUMEN
Based on the Gaussian-based quantitative structure-activity relationship (QSAR) and virtual screening (VS) processes, some promising acetylcholinesterase inhibitors (AChEIs) having antioxidant potential were designed synthesized, characterized, and evaluated for their ability to enhance learning and memory. The synthesized phenyl benzoxazole derivatives exhibited significant antioxidant potential and AChE inhibitory activity, whereas the antioxidant potential of compound 34 (49.6%) was observed significantly better than standard donepezil (<10%) and parallel to ascorbic acid (56.6%). Enzyme kinetics study of most potent compound 34 (AChE IC50â¯=â¯0.363⯱â¯0.017⯵M; Kiâ¯=â¯0.19⯱â¯0.03⯵M) revealed the true nature and competitive type of inhibition on AChE. The compound 34 was further assessed for in vivo and ex vivo studies and the results showed the significant reversal of cognitive deficits and antioxidant potential at the dose of 5â¯mg/kg comparable to standard drug donepezil.
Asunto(s)
Benzoxazoles/síntesis química , Inhibidores de la Colinesterasa/farmacología , Diseño de Fármacos , Antioxidantes/síntesis química , Antioxidantes/farmacología , Benzoxazoles/farmacología , Inhibidores de la Colinesterasa/uso terapéutico , Humanos , Aprendizaje/efectos de los fármacos , Memoria/efectos de los fármacos , Farmacocinética , Relación Estructura-Actividad CuantitativaRESUMEN
The diverse nature of Alzheimer's disease (AD) has prompted researchers to develop multi-functional agents. Herein, we have designed and synthesized molecular hybrids of 2-pyridylpiperazine and 5-phenyl-1,3,4-oxadiazoles. Biological activities of synthesized compounds suggested significant and balanced inhibitory potential against target enzymes. In particular, compound 49 containing 2,4-difluoro substitution at terminal phenyl ring considered as most potential lead with inhibition of acetylcholinesterase (hAChE, IC50â¯=â¯0.054⯵M), butyrylcholinesterase (hBChE, IC50â¯=â¯0.787⯵M) and beta-secretase-1 (hBACE-1, IC50â¯=â¯0.098⯵M). The enzyme kinetics study of 49 against hAChE suggested a mixed type of inhibition (Kiâ¯=â¯0.030⯵M). Also, 48 and 49 showed significant displacement of propidium iodide from the peripheral anionic site (PAS) of hAChE, excellent blood-brain barrier (BBB) permeability in parallel artificial membrane permeation assay (PAMPA), and neuroprotective ability against SH-SY5Y neuroblastoma cell lines. Further, 49 also exhibited anti-Aß aggregation activity in self- and AChE-induced thioflavin T assay, which was ascertained by morphological characterization by atomic force microscopy (AFM). Moreover, in vivo behavioral studies signified learning and memory improvement by compound 49 in scopolamine- and Aß-induced cognitive dysfunctions performed on Y-maze and Morris water maze. The ex vivo studies suggested decreased AChE activity and antioxidant potential of compound 49, with good oral absorption characteristics ascertained by pharmacokinetic studies.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Fármacos Neuroprotectores/química , Oxadiazoles/química , Piperazinas/química , Piridinas/química , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/psicología , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Animales , Antioxidantes/química , Antioxidantes/farmacología , Barrera Hematoencefálica/metabolismo , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacocinética , Disfunción Cognitiva/tratamiento farmacológico , Femenino , Humanos , Cinética , Simulación del Acoplamiento Molecular , Fármacos Neuroprotectores/farmacocinética , Oxadiazoles/farmacocinética , Piperazinas/farmacocinética , Agregado de Proteínas , Piridinas/farmacocinética , Ratas Wistar , Relación Estructura-ActividadRESUMEN
BACKGROUND: Nipecotic acid is considered to be one of the most potent inhibitors of neuronal and glial γ-aminobutyric acid (GABA) uptake in vitro. However, nipecotic acid does not readily cross the blood-brain barrier (BBB) following peripheral administration, owing to its hydrophilic nature. OBJECTIVE: A series of substituted acetonaphthones tethered nipecotic acid derivatives were designed and synthesized with an aim to improve the lipophilicity and the blood-brain barrier (BBB) permeation. METHODS: Synthesized compounds were tested in mice models of PTZ, pilocarpine, and DMCM induced epilepsy, in vivo. The rota-rod test was performed to determine the acute neurotoxicity of the potential leads (4a, 4b, and 4i). These potential hybrids were also evaluated for their ability to cross the BBB by an in vitro parallel artificial membrane permeability BBB assay (PAMPA-BBB). The leads were subjected to in silico molecular docking and dynamics studies on homology modelled protein of human GABA (γ-amino butyric acid) transporter 1 (GAT1) and prediction of their pharmacokinetic properties. RESULT: Amongst the synthesized derivatives, compounds 3a, 3b, 3i, 4a, 4b, and 4i exhibited increased latency of seizures against subcutaneous pentylenetetrazole (scPTZ) induced seizures in mice. Derivatives 4a, 4b, 4i were more effective compared to nipecotic acid ester counterparts 3a, 3b and 3i placing the importance of the presence of free carboxyl group in the centre. The findings revealed that 4i was comparatively more permeable (Pe= 8.89) across BBB than the standard tiagabine (Pe= 7.86). In silico studies proved the consensual interactions of compound 4i with the active binding pocket. CONCLUSION: Some nipecotic acid-acetonaphthone hybrids with considerable anti-epileptic activity, drug like properties and the ability to permeate the BBB have been successfully synthesized.
Asunto(s)
Anticonvulsivantes/uso terapéutico , Epilepsia/tratamiento farmacológico , Naftalenos/uso terapéutico , Ácidos Nipecóticos/uso terapéutico , Animales , Anticonvulsivantes/síntesis química , Anticonvulsivantes/química , Barrera Hematoencefálica/metabolismo , Modelos Animales de Enfermedad , Drosophila , Diseño de Fármacos , Femenino , Proteínas Transportadoras de GABA en la Membrana Plasmática/química , Inhibidores de Recaptación de GABA/síntesis química , Inhibidores de Recaptación de GABA/química , Inhibidores de Recaptación de GABA/uso terapéutico , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Masculino , Ratones , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Naftalenos/síntesis química , Naftalenos/química , Ácidos Nipecóticos/síntesis química , Ácidos Nipecóticos/química , TiagabinaRESUMEN
BACKGROUND: Nifedipine is a potential therapeutic agent for the treatment of cardiovascular disturbances, although it suffers from short half-life (t1/2, 2 hr). OBJECTIVE: To address the problem, we first prepared nifedipine loaded sustained release microsponges and then formulated tablets for effective clinical application and patient compliance. METHOD: Preparations of microsponges were carried out using different compositions of nifedipine and polymer (1:1, 1:2 and 1:3 % molar ratio) using emulsion solvent diffusion technique. RESULTS: The microsponges with molar ratio 1:3 (formulation code: MF-3) found optimized as revealed by analyzing surface morphology, better powder flow properties (angle of repose; 28.80 ± 0.9, Hausner ratio 1.15 ± 0.2, % compressibility 15.28 ± 0.5% and higher % drug content (80 ± 1.9 %). Different batches of tablets were then formulated incorporating MF-3 microsponges and different proportions (10-50 %) of microcrystalline cellulose and starch as additives. Among tablet formulations, batch composed of 48% of MF-3, 30% of MCC, 20 % of starch and 2 % of talc (TF-33), showed 92.73 ± 2.19 % drug release during 24 hr in vitro release study in comparison to other batches including commercial formulation which was found to be released completely in 20 hr. Further, stability analysis revealed good drug retention of loaded nifedipine as well as consistent in vitro release pattern over a period of 90 days at 40°C and 75% RH. CONCLUSION: The microsponge tablet delivery system was found to be superior concerning the therapeutic advantage as well as manufacturing feasibility of nifedipine.