Antibacterial potential of Thymus linearis essential oil collected from Wasturwan mountain: A combination of experimental and theoretical studies involving in silico molecular docking simulation of the major compounds against Novobiocin-resistant mutant of DNA Gyrase-B.

Antibiotic resistant bacteria are immune to most antibiotics and are therefore very difficult to treat and in most cases lead to death. As such there is a pressing need for alternative and more efficient antibacterial drugs which can target these drug-resistant strains as well. The objective of this research work was to investigate the antibacterial properties of Thymus linearis essential oil (EO) against multiple disease-causing bacterial pathogens. Additionally, the study aimed to examine the molecular docking and molecular dynamic (MD) simulations of the primary components of the EO with the essential bacterial proteins and enzymes. Gas chromatography-mass spectrometry was employed to analyse the chemical composition of Thymus linearis EO. The initial screening for antibacterial properties involved the use of disc diffusion and microdilution techniques. Molecular docking studies were conducted utilising Autodock Vina. The outcomes were subsequently visualised through BIOVIA Discovery Studio. MD simulations were conducted using iMODS, an internet-based platform designed for MD simulations. The essential oil (EO) was found to contain 26 components, with thymol, carvacrol, p-cymene, and γ-terpinene being the primary constituents. The study findings revealed that Thymus linearis EO demonstrated antibacterial effects that were dependent on both the dose and time. The results of molecular docking studies revealed that the primary constituents of the EO, namely thymol, carvacrol, and p-cymene, exhibited robust interactions with the active site of the bacterial DNA gyrase enzyme. This finding provides an explanation for the antibacterial mechanism of the EO. The results indicate that Thymus linearis EO possesses potent antibacterial properties against the MDR microorganisms. Molecular docking analyses revealed that the essential oil's primary components interact with the amino acid residues of the DNA-Gyrase B enzyme, resulting in a favourable docking score.

Differential regulation of NM23-H1 under hypoxic and serum starvation conditions in metastatic cancer cells and its implication in EMT.

Multiple stresses are prevalent inside the tumor microenvironment rendering tumor growth, neighboring invasion and metastasis of the cancer cells to distant organs. NM23-H1 is the first metastasis suppressor gene identified and known to be implicated as an important regulator of stress-induced metastasis. Herein, we demonstrated that prototypical NM23-H1 expression diminished during hypoxia and serum starvation in Panc-1/MDA-MB-231 cells, but converse invasion patterns were obtained in these two diverse stresses. Supportingly, a compelling discrete difference in mRNA and protein levels of NM23-H1 was achieved in hypoxia as well as serum starvation. Knockdown of NM23-H1 activates EMT whereas the similar effects are subdued in serum starvation where NM23-H1 down-modulation prompted E-cadherin upregulation. Stable NM23-H1 expression augmented E-cadherin levels along with retardation in invadopodea formation and invasion. In hypoxia/serum starvation excess NM23-H1 effectively modulated the Twist1 promoter activity. Thus, differential regulation of NM23-H1 may corroborate/abrogate EMT depending on the nature of stress, tumor microenvironment and cellular context.

Alkyne-azide cycloaddition analogues of dehydrozingerone as potential anti-prostate cancer inhibitors via the PI3K/Akt/NF-kB pathway.

Herein, we report the isolation and synthetic modification of dehydrozingerone (DHZ, 1), a secondary metabolite present in the rhizome of Zingiber officinale. We synthesized O-propargylated dehydrozingerone, which was subsequently coupled by alkyne-azide cycloaddition (3-20) using click chemistry. The compounds (1-20) were evaluated for their in vitro cytotoxic activity in a panel of three cancer cell lines. Among all the DHZ derivatives, 3, 6, 7, 8, 9 and 15 displayed potent cytotoxic potential with an IC50 value ranging from 1.8-3.0 µM in MCF-7, PC-3 and HCT-116 cell lines. Furthermore, compound 7 has proven to be the most potent cytotoxic compound in all the three distinct cancer cell lines and also demonstrated significant anti-invasive potential in prostate cancer. The mechanistic study of compound 7 showed that it not only suppressed the AKT/mTOR signalling which regulates nuclear transcription factor-NF-kB but also augmented the expression of anti-invasive markers E-cadherin and TIMP. Compound 7 significantly decreased the expression of pro-invasive markers vimentin, MMP-2 and MMP-9, respectively. This study underscores an efficient synthetic approach employed to evaluate the structure-activity relationship of dehydrozingerone (1) in search of potential new anticancer agents.