Comparative analysis of binding affinities between styrene and mammalian CYP2E1 by bioinformatics approaches

Sodium alginate emulsion loaded with linalool: Preparation, characterization and antibacterial mechanism against Shigella sonnei

This study aimed to prepare sodium alginate-linalool emulsion (SA-LE) to overcome the low solubility of linalool and explore its inhibitory activity against Shigella sonnei. The results indicated that linalool significantly reduced the interfacial tension between SA and oil phase (p < 0.05). Droplet sizes of fresh emulsions were uniform with sizes from 2.54 to 2.58 μm. The ζ-potential was between -23.94 and -25.03 mV, and the viscosity distribution was 973.62 to 981.03 mPa·s at pH 5-8 (near neutral pH) without significant difference. In addition, linalool could be effectively released from SA-LE in accordance with the Peppas-Sahlin model, mainly described by Fickian diffusion. In particular, SA-LE can inhibit S. sonnei with a minimum inhibitory concentration of 3 mL/L, which was lower than free linalool. The mechanism can be described as damaging the membrane structure and inhibiting respiratory metabolism accompanied by oxidative stress based on FESEM, SDH activity, ATP and ROS content. These results suggest that SA is an effective encapsulation strategy to enhance the stability of linalool and its inhibitory effect on S. sonnei at near neutral pH. Moreover, the prepared SA-LE has the potential to be developed as a natural antibacterial agent to address the growing food safety challenges.

QSAR Studies of Sulfonamide Hydroxamates Derivatives as MMP-2 Inhibitors Topomer CoMFA and Molecular Docking

Background:

In recent years, cancer has become the main cause of death and it is a serious threat to human health, so the development of new, selective and safe anticancer drugs is still the focus of medical research. Matrix metalloproteinases-2 (MMP-2) has been determined to play an important role in the regulation of tumor angiogenesis, which is closely related to the development of the tumor. Therefore, MMP-2 is considered as a promising target for tumor therapy. In this study, Tomper comparative molecular field analysis (Topomer CoMFA) and molecular docking were used to investigate the important role of sulfonamide hydroxamate derivatives, an inhibitor of MMP-2, in the inhibition of angiogenesis.

Methods:

Quantitative structure active relationship (QSAR) models of 35 sulfonamide hydroxamate derivatives with inhibitory MMPs were developed. The quantitative structure-activity relationship (QSAR) model was built by using Topomer comparative molecular field analysis (Topomer CoMFA) technique.

Results and Conclusion:

The results show that the cross-validated q2 value of the Topomer CoMFA model is 0.881 and the non-cross-validated r2 value is 0.967. The results show that the model is reasonable and reliable, and has good prediction ability. Molecular docking studies were used to find the actual conformations of chemicals in active sites of cancer protease, as well as the binding mode pattern to the binding site in MMP-2. The information provided by the 3D-QSAR model and molecular docking may lead to a better understanding of the structural requirements of 35 sulfonamide hydroxamate derivatives and help to design potential anti-cancer protease inhibitor molecules.

Conclusion:

Thirty-five analogs were used in the 3D-QSAR study. Topomer CoMFA 3D-QSAR method was used to build the model, and the model was well predicted and statistically validated. The results of 3D-QSAR and molecular docking analysis provide theoretical guidance for the synthesis of new MMP-2 inhibitors.

Interactions of inhibitor molecules with the human CYP2E1 enzyme active site

CYP2E1 is an important enzyme oxidizing ethanol as well as several drugs and other xenobiotics in the human liver. We determined the inhibition potency of structurally diverse compounds against human CYP2E1, and analyzed their interactions with the enzyme active site by molecular docking and 3D-QSAR approaches. The IC(50) values for the tested compounds varied from 1.4 μM for γ-undecanolactone to over 46 mM for glycerol. This data set was used to create a comparative molecular field analysis (CoMFA) model. The most important interactions for binding of inhibitors were identified by docking and key features for inhibitors were characterized via the COMFA model. Since the active site of CYP2E1 is flexible, long chain lactones and alkyl alcohols fitted best into the larger open form while the other compounds fitted better in the smaller closed form of the active site. Electrostatic interactions near the Thr(303) residue proved to be important for inhibition of the enzyme activity. Thus, docking analysis and the predictive CoMFA model proved to be efficient tools for revealing interactions between inhibiting compounds and CYP2E1. These approaches can be used to analyze CYP2E1-mediated metabolism and drug interactions in the development of new chemical entities.