Biological evaluation and interaction mechanism of beta-site APP cleaving enzyme 1 inhibitory pentapeptide from egg albumin

Inhibition of beta-site APP cleaving enzyme1(BACE1)is one of the most promising therapeutic approaches for Alzheimer’s disease.To find natural products for the treatment of Alzheimer’s disease,absorption,distribution,metabolism,excretion and toxicity(ADMET)properties and in vitro BACE1 inhibitory activity of the peptides isolated from egg albumin were evaluated.Then,molecular docking and molecular dynamics simulation were used to explain the molecular mechanism of the interactions between BACE1 and peptides.The IC50 value of peptide KLPGF,with satisfactory ADMET properties,against BACE1 was(8.30±0.56)mmol/L.Molecular docking revealed that KLPGF contacted with the residues of BACE1’s active sites through twelve hydrogen bonds interactions,two hydrophobic interactions,one electrostatic interaction,and two Pi-cation interactions.The 5 ns molecular dynamics simulations confirmed that the structure of KLPGF with BACE1 was stable.Peptide KLPGF contacted the residues Lys321,Asp228,and Asn233 with stable hydrogen bonds.KLPGF may be a potential anti-BACE1 candidate.

Study of Aldo-keto Reductase 1C3 Inhibitor with Novel Framework for Treating Leukaemia Based on Virtual Screening and In vitro Biological Activity Testing

Aldo-keto reductase 1C3(AKR1C3)is a potential target for the treatment of acute myeloid leukaemia and T-cell acute lymphoblastic leukaemia.In this study,pharmacophore models,molecular docking and virtual screening of target prediction were used to find a potential AKR1C3 inhibitor.Firstly,eight bacteriocin derivatives(Z1-Z8)were selected as training sets to construct 20 pharmacophore models.The best pharmacophore model MODEL_016 was obtained by Decoy test(the enrichment degree was 21.5117,and the fitting optimisation degree was 0.9668).Secondly,MODEL_016 was used for the virtual screening of ZINC database.Thirdly,the hit 83256 molecules were docked into the AKR1C3 protein.Compared to the total scores and interactions between compounds and protein,16532 candidate compounds with higher docking scores and interactions with important residues PHE306 and TRP227 were screened.Lastly,eight compounds(A1-A8)that had good absorption,distribution,metabolism,excretion and toxicity(ADMET)properties were obtained by target prediction.Compounds A3 and A7 with high total score and good target prediction results were selected for in vitro biological activity test,whose IC_(50) values were 268.3 and 88.94µmol/L,respectively.The results provide an important foundation for the discovery of novel AKR1C3 inhibitors.The research methods used in this study can also provide important references for the research and development of new drugs.