Molecular docking and molecular dynamic simulations of apoptosis proteins with potential anticancer compounds present in Clinacanthus nutans extract using gas chromatography-mass spectrometry.

Clinacanthus nutans is a medicinal plant recognised for its anticancer properties. We previously discovered that the C. nutans extract had the most potent inhibitory effect on MCF7 breast cancer cell and significantly induced apoptosis. However, there is a scarcity of studies demonstrating the molecular interactions of C. nutans-derived chemical compounds associated with apoptosis-related proteins. Therefore, the objective of this study was to determine the potential chemical compounds found in the C. nutans extract and examine their interactions with the targeted apoptotic proteins using molecular docking and molecular dynamic simulations. To address this objective, the compounds found in the SF2 extract of C. nutans were analysed using Gas Chromatography-Mass Spectrometry (GC-MS). The molecular interaction of the compounds with the targeted apoptotic proteins were determined using molecular docking and molecular dynamic simulations. GC-MS analysis revealed a total of 32 compounds in the SF2 extract. Molecular docking analysis showed that compound ß-amyrenol had the highest binding affinity for MDM2-P53 (-7.26 kcal/mol), BCL2 (-11.14 kcal/mol), MCL1-BAX (-6.42 kcal/mol), MCL1-BID (-6.91 kcal/mol), and caspase-9 (-12.54 kcal/mol), whereas campesterol had the highest binding affinity for caspase-8 (-10.11 kcal/mol) and caspase-3 (-10.14 kcal/mol). These selected compounds were subjected to molecular dynamic simulation at 310 K for 100 ns. The results showed that the selected protein-ligand conformation complexes were stable, compact, and did not alter much when compared to the protein references. The findings indicate that ß-amyrenol and campesterol are potentially significant compounds that might provide insight into the molecular interactions of the compounds with the apoptosis-related proteins.Communicated by Ramaswamy H. Sarma.

Cytotoxicity and Genotoxicity of Biogenic Silver Nanoparticles in A549 and BEAS-2B Cell Lines.

Introduction: Biogenic silver nanoparticles (AgNPs-GA) were successfully synthesised using Garcinia atroviridis leaf extract as a reducing agent, which has ethnopharmacological claims against various diseases including cancer. Aim of the Study. Aim of the study is to discover whether AgNPs-GA has cytotoxic and genotoxic effects on cancerous (A549) and noncancerous (BEAS-2B) human lung cells. Materials and Methods: The cytotoxicity profiles of AgNPs-GA were characterized by MTT assay, intracellular reactive oxygen species (ROS) assay, and DAPI and AOPI double staining, whilst genotoxicity was assessed using Comet Assay analysis. The level of silver ions (Ag+) and cellular uptake of AgNPs-GA were evaluated by ICP-OES and TEM analyses, respectively. Results: A significant cytotoxic effect was observed by AgNPs-GA on both A549 and BEAS-2B cell lines, with IC50 values of 20-28 µg/ml and 12-35 µg/ml, respectively. The cytotoxicity profile of AgNPs-GA was also accompanied by a pronounced increase in ROS production, DNA damage, and apoptosis. Moreover, Ag+ was also detected in cells exposed to AgNPs-GA threefold higher compared to controls. In this study, AgNPs-GA were endocytosed within lysosomes, which may direct to secondary toxicity effects including oxidative stress, impairment of the cell membrane, DNA fragmentation, and cell death. Conclusions: Taken together, novel toxicological-related mechanisms by AgNPs-GA were proposed involving the generation of ROS that causes DNA damage which led to programmed cell death in both A549 and BEAS-2B cells. Therefore, a combination of scientific assessments is constantly needed to ensure that the quality of biosynthesized nanoparticles is controlled and their safe development is promoted.