2023-11-25·Journal of biomolecular structure & dynamics
Synthesis and computational insights of flavone derivatives as potential estrogen receptor alpha (ER-α) antagonist.
作者: Bharti S Fegade ; Shailaja B Jadhav ; Somdatta Y Chaudhari ; Deepak T Tandale ; Pravin Shantaram Uttekar ; Shams Tabrez ; Mohd Shahnawaz Khan ; Syed Kashif Zaidi ; Nobendu Mukerjee ; Arabinda Ghosh
Hormone-related breast cancer is mostly caused by interactions with estrogen receptor alpha (ER-α), which functions as a transcription factor to control the transcription of numerous genes. Flavones are considered a good substrate for the estrogen receptor. Substitution of the N-heterocyclic ring on the flavon structure may potentiate its anticancer effect. A series of flavon derivatives with an N-heteroaryl ring at the 4' position of the B ring of flavon were designed, prepared and evaluated for in vitro breast cancer activity. Binding interactions of the PzFL, PzF, PiFL, PiF and IFL compounds with ER-α were studied by molecular docking. Molecular dynamics simulation studies were carried out in order to determine the stability and convergence of protein-ligand complexes. The compounds were produced by cyclizing chalcones and chalcones were produced by Claisen-Schmidt condensation of substituted aldehydes and 2-hydroxy acetophenone. Breast cancer activity was evaluated by the MTT assay on MCF-7 cell lines. Also, compounds were studied for their estrogen receptor binding potential on the same cell lines. Molecular docking of compounds showed a good docking score. The molecular dynamics of these compounds expressed stable root mean square deviation, stable radius of gyration and low binding energy, suggesting that ligand bound to protein is quite stable in the complex. MTT assay on MCF-7 cell lines reported PzF and IFL were the most active compounds with lower IC50 values. ER-α binding assay of these compounds revealed the presence of binding interactions with receptors. This study offers a viable reference point for the design of flavon-incorporated N-heterocyclic ring derivatives as breast cancer compounds.Communicated by Ramaswamy H. Sarma.
2023-10-08·Journal of controlled release : official journal of the Controlled Release Society
The alpha-adrenergic antagonist prazosin promotes cytosolic siRNA delivery from lysosomal compartments.
作者: Thijs Van de Vyver ; Cristina Muntean ; Iuliia Efimova ; Dmitri V Krysko ; Lynn De Backer ; Stefaan C De Smedt ; Koen Raemdonck
The widespread use of small interfering RNA (siRNA) is limited by the multiple extra- and intracellular barriers upon in vivo administration. Hence, suitable delivery systems, based on siRNA encapsulation in nanoparticles or its conjugation to targeting ligands, have been developed. Nevertheless, at the intracellular level, these state-of-the-art delivery systems still suffer from a low endosomal escape efficiency. Consequently, the bulk of the endocytosed siRNA drug rapidly accumulates in the lysosomal compartment. We recently reported that a wide variety of cationic amphiphilic drugs (CADs) can promote small nucleic acid delivery from the endolysosomal compartment into the cytosol via transient induction of lysosomal membrane permeabilization. Here, we describe the identification of alternate siRNA delivery enhancers from the NIH Clinical Compound Collection that do not have the typical physicochemical properties of CADs. Additionally, we demonstrate improved endolysosomal escape of siRNA via a cholesterol conjugate and polymeric carriers with the α1-adrenergic antagonist prazosin, which was identified as the best performing delivery enhancer from the compound screen. A more detailed assessment of the mode-of-action of prazosin suggests that a different cellular phenotype compared to typical CAD adjuvants drives cytosolic siRNA delivery. As it has been described in the literature that prazosin also induces cancer cell apoptosis and promotes antigen cross-presentation in dendritic cells, the proof-of-concept data in this work provides opportunities for the repurposing of prazosin in an anti-cancer combination strategy with siRNA.
2023-09-15·bioRxiv : the preprint server for biology
Comparative cardiotoxicity assessment of bisphenol chemicals and estradiol using human induced pluripotent stem cell-derived cardiomyocytes.
作者: Blake L Cooper ; Shatha Salameh ; Nikki Gillum Posnack
Bisphenol A (BPA) is commonly used to manufacture consumer and medical-grade plastics. Due to health concerns, BPA substitutes are being incorporated - including bisphenol S (BPS) and bisphenol F (BPF) - without a comprehensive understanding of their toxicological profile.
Previous studies suggest that bisphenol chemicals perturb cardiac electrophysiology in a manner that is similar to 17β-estradiol (E2). We aimed to compare the effects of E2 with BPA, BPF, and BPS using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM).
Cardiac parameters were evaluated using microelectrode array (MEA) technology and live-cell fluorescent imaging at baseline and in response to chemical exposure (0.001-100 μM).
Cardiac metrics remained relatively stable after exposure to nanomolar concentrations (1-1,000 nM) of E2, BPA, BPF, or BPS. At higher micromolar concentrations, chemical exposures resulted in a decrease in the depolarizing spike amplitude, shorter field potential and action potential duration, shorter calcium transient duration, and decrease in hiPSC-CM contractility (E2 > BPA > BPF >> BPS). Cardiomyocyte physiology was largely undisturbed by BPS exposure. BPA-induced effects were exaggerated when co-administered with an L-type calcium channel antagonist (verapamil) or E2 - and reduced when co-administered with an L-type calcium channel agonist (Bay K8644) or an estrogen receptor alpha antagonist (MPP). E2-induced effects generally mirrored those of BPA, but were not exaggerated by co-administration with an L-type calcium channel antagonist.
Collectively across multiple cardiac endpoints, E2 was the most potent and BPS was the least potent disruptor of hiPSC-CM function. Although the observed cardiac effects of E2 and BPA were similar, a few distinct differences suggest that these chemicals may act (in part) through different mechanisms. hiPSC-CM are a useful model for screening cardiotoxic chemicals, nevertheless, the described in vitro findings should be validated using a more complex ex vivo and/or in vivo model.