Résumé
Transient receptor potential vanilloid member 3 (TRPV3) is a temperature-sensitive cation channel protein, which contributes to nociception, itch, hair growth, emotional control and the pathophysiology of migraine. However, research progress on TRPV3 fundamental molecular biology is rather slow, compared to other TRP channels due to the lack of its selective antagonists. It's necessary to identify TRPV3 selective antagonists for the study on TRPV3 physiological functions. In this study, several selective TRPV3 antagonists were identified by ligand-based virtual screening of shape-based similarity and electrostatic matching. The most potent one (V-39) blocked 2-APB-activated currents in a stable human TRPV3 expressed HEK293T cell line with IC50=18.0 ±1.1 μmol·L-1 (n=4). Besides, the interaction pattern between TRPV3 and its antagonists were studied through docking the antagonists into a homology model (TRPV3_HM4) generated from the crystal structure of TPRV1. The docking results show that the binding site of TRPV3 locates between linker domain (of N-terminus and TM1) and TRP Box. There are a π-π stacking interaction and hydrogen bonding interactions between compound V-39 and residues His-310, His-314 and Arg-577 of the pocket. Identification of these antagonists provides new probes for understanding the pharmacological function of TRPV3 channel.
Résumé
MEK inhibition activates PI3K/AKT/mTOR pathway in triple negative breast cancer (TNBC) cell lines. Combination of PI3K inhibitor and MEK1/2 inhibitor is not appropriate for PI3K inhibitor insensitive TNBC cell lines. This study was designed to investigate the effects of dual treatments with mTOR1/2 inhibitor AZD8055 and MEK1/2 inhibitor PD0325901 in MDA-MB-435 cell line. MEK1/2 inhibition led to activation of AKT, which is the downstream signaling protein of PI3K pathway. The combination inhibited the phosphorylation of AKT and therefore abolished the feedback interaction of two pathways. Cell proliferation assay and DNA replication assay demonstrated that the dual treatments led to a significant synergistic inhibition of cell cycle progression and cell proliferation.
Résumé
CD38 is a multifunctional enzyme expressed in a variety of mammalian tissues, its catalytic activity was involved in a wide range of physiological processes. Based on the reported inhibitor of human CD38 NADase, 33 purine derivatives were designed and synthesized. The biological activity assay showed that compounds 20 and 38 exhibited almost the same extent of inhibitory activities on human CD38 NADase as the lead compound H2. The results also revealed that small substituents at C-6 of purine ring gave no obvious effect on inhibitory activity, but phenylpropionyl moiety at N-2 could affect the binding mode of the compound with CD38. This study provides a reliable basis for future rational design of inhibitors for CD38.
Sujets)
Humains , Antigènes CD38 , Antienzymes , Chimie , Purines , ChimieRésumé
Photoaffinity labeling is widely applied to demonstrate targets of small molecule ligands. In this paper, biotin photoaffinity labeled molecule with propargyl group 1 has been designed and synthesized, followed it's labeling of N2-acetyl-2'-O-propargyl guanosine 9 by "click chemistry". This technology presents delight development potential in labeling of second messenger cyclic nucleotide, antisense oligonucleotide or siRNA.
Sujets)
Biotine , Chimie , Chimie click , Guanosine , Chimie , Ligands , Marqueurs de photoaffinitéRésumé
Ubiquitin-proteasome pathway (UPP) is one of the ways utilized for selective degradation of many proteins in cells, and the 20S proteasome takes the functional machinery where hydrolysis of targeted proteins takes place. Based on existing peptide inhibitors, a series of novel tripeptidic tetrazoles have been designed, synthesized, and the structures have been confirmed with 1H NMR, MS and elemental analysis. Among them, three compounds (6b, 6d and 6h) showed inhibitory activities of ChT-L of 20S proteasome.