Favipiravir is found to show excellent in-vitro inhibition activity against Nipah virus. To explore the structure–property relationship of Favipiravir, in silico designing of a series of piperazine substituted Favipiravir derivatives are attempted and computational screening has been done to evaluate its bimolecular interactions with Nipah virus. The geometrical features of all the molecules have been addressed from Density Functional Theory calculations. Chemical reactivity descriptor analysis was carried out to understand various reactivity parameters. The drug-likeness properties were estimated by a detailed ADMET study. The binding ability and the mode of binding of these derivatives into the Nipah virus are obtained from molecular docking studies. Our calculations show greater binding ability for the designed inhibitors compared to that of the experimentally reported molecule. Overall, the present work proves to offers new insights and guidelines for synthetic chemists to develop new drugs using piperazine substituted Favipiravir in the treatment of Nipah virus.
1 July 2018 in International Journal of Biological Macromolecules
The global impact of Alzheimer’s disease (AD) necessitates intensive research to find appropriate and effective drugs. Many studies in AD suggested beta-amyloid plaques and neurofibrillary tangles-associated tau protein as the key targets for drug development. On the other hand, it is proved that triggering of Glycogen Synthase Kinase-3β (GSK-3β) also cause AD, therefore, GSK-3β is a potential drug target to combat AD. We, in this study, investigated the ability of small molecules to inhibit GSK-3β through virtual screening, Absorption, Distribution, Metabolism, and Excretion (ADME), induced-fit docking (IFD), molecular dynamics simulation, and binding free energy calculation. Besides, molecular docking was performed to reveal the binding and interaction of the ligand at the active site of GSK-3β. We found two compounds such as 6961 and 6966, which exhibited steady-state interaction with GSK-3β for 30 ns in molecular dynamics simulation. The compounds (6961 and 6966) also achieved a docking score of −9.05 kcal/mol and −8.11 kcal/mol, respectively, which is relatively higher than the GSK-3β II inhibitor (−6.73 kcal/mol). The molecular dynamics simulation revealed that the compounds have a stable state during overall simulation time, and lesser root-mean-square deviation (RMSD) and root-mean-square fluctuation (RMSF) values compared with co-crystal. In conclusion, we suggest the two compounds (6966 and 6961) as potential leads that could be utilized as effective inhibitors of GSK-3β to combat AD. Communicated by Ramaswamy H. Sarma
Helicobacter pylori (H. pylori)—a human gastric pathogen—forms a major risk factor for the development of various gastric pathologies such as chronic inflammatory gastritis, peptic ulcer, lymphomas of mucosa-associated lymphoid tissues, and gastric carcinoma. The complete eradication of infection is the primary objective of treating any H. pylori-associated gastric condition. However, declining eradication efficiencies, off-target effects, and patient noncompliance to prolong and broad-spectrum antibiotic treatments has spurred the clinical interest to search for alternative effective and safer therapeutic options. As natural compounds are safe and privileged with high levels of antibacterial-activity, previous studies have tested and reported a plethora of such compounds with potential in vitro/in vivo anti-H. pylori activity. However, the mode of action of majority of these natural compounds is unclear. The present study has been envisaged to compile the information of various such natural compounds and to evaluate their binding with histone-like DNA-binding proteins of H. pylori (referred here as Hup) using in silico molecular docking-based virtual screening experiments. Hup—being a major nucleoid-associated protein expressed by H. pylori—plays a strategic role in its survival and persistent colonization under hostile stress conditions. The ligand with highest binding energy with Hup—that is, epigallocatechin-(−)gallate (EGCG)—was rationally selected for further computational and experimental testing. The best docking poses of EGCG with Hup were first evaluated for their solution stability using long run molecular dynamics simulations and then using fluorescence and nuclear magnetic resonance titration experiments which demonstrated that the binding of EGCG with Hup is fairly strong (the resultant apparent dissociation constant (kD) values were equal to 2.61 and 3.29 ± 0.42 μM, respectively).
1 September 2018 in Journal of Hazardous Materials
Protein kinases are ubiquitously expressed as Serine/Threonine kinases, and play a crucial role in cellular activities. Protein kinases have evolved through stringent regulation mechanisms. Protein kinases are also involved in tauopathy, thus are important targets for developing Anti-Alzheimer’s disease compounds. Structures with an indole scaffold turned out to be potent new leads. With the aim of developing new inhibitors for human protein kinase C, here we report the generation of four point 3D geometric featured pharmacophore model. In order to identify novel and potent PKCθ inhibitors, the pharmacophore model was screened against 80,000,00 compounds from various chemical databases such as., ZINC, SPEC, ASINEX, which resulted in 127 compound hits, and were taken for molecular docking filters (HTVS, XP docking). After in-depth analysis of binding patterns, induced fit docking (flexible) was employed for six compounds along with the cocrystallized inhibitor. Molecular docking study reveals that compound 6F found to be tight binder at the active site of PKCθ as compared to the cocrystal and has occupancy of 90 percentile. MM-GBSA also confirmed the potency of the compound 6F as better than cocrystal. Molecular dynamics results suggest that compound 6F showed good binding stability of active sites residues similar to cocrystal 7G compound. Present study corroborates the pharmacophore-based virtual screening, and finds the compound 6F as a potent Inhibitor of PKC, having therapeutic potential for Alzheimer’s disease. Worldwide, 46.8 million people are believed to be living with Alzheimer’s disease. When elderly population increases rapidly and neurodegenerative burden also increases in parallel, we project the findings from this study will be useful for drug developing efforts targeting Alzheimer’s disease.