ABSTRACT
Isorhamnetin (C16H12O7), a 3'-O-methylated derivative of quercetin from the class of flavonoids, is predominantly present in the leaves and fruits of several plants, many of which have traditionally been employed as remedies due to its diverse therapeutic activities. The objective of this in-depth analysis is to concentrate on Isorhamnetin by addressing its molecular insights as an effective anticancer compound and its synergistic activity with other anticancer drugs. The main contributors to Isorhamnetin's anti-malignant activities at the molecular level have been identified as alterations of a variety of signal transduction processes and transcriptional agents. These include ROS-mediated cell cycle arrest and apoptosis, inhibition of mTOR and P13K pathway, suppression of MEK1, PI3K, NF-κB, and Akt/ERK pathways, and inhibition of Hypoxia Inducible Factor (HIF)-1α expression. A significant number of in vitro and in vivo research studies have confirmed that it destroys cancerous cells by arresting cell cycle at the G2/M phase and S-phase, down-regulating COX-2 protein expression, PI3K, Akt, mTOR, MEK1, ERKs, and PI3K signaling pathways, and up-regulating apoptosis-induced genes (Casp3, Casp9, and Apaf1), Bax, Caspase-3, P53 gene expression and mitochondrial-dependent apoptosis pathway. Its ability to suppress malignant cells, evidence of synergistic effects, and design of drugs based on nanomedicine are also well supported to treat cancer patients effectively. Together, our findings establish a crucial foundation for understanding Isorhamnetin's underlying anti-cancer mechanism in cancer cells and reinforce the case for the requirement to assess more exact molecular signaling pathways relating to specific cancer and in vivo anti-cancer activities.
Subject(s)
Neoplasms , Quercetin , Humans , Quercetin/pharmacology , Quercetin/analogs & derivatives , Neoplasms/drug therapy , Neoplasms/pathology , Animals , Signal Transduction/drug effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Apoptosis/drug effectsABSTRACT
Objective: Despite the development of several vaccines against severe acute respiratory syndrome coronavirus-2, the need for an additional prophylactic agent is evident. In recent in silico studies, isovitexin exhibited a higher binding affinity against the human angiotensin converting-enzyme 2 (hACE2) receptor than existing antiviral drugs. The research aimed to find out the point specificity of isovitexin for the hACE2 receptor and to assess its therapeutic potential, depending on the stability of the isovitexin-hACE2 complex. Materials and Methods: The pharmacokinetic profile of isovitexin was analyzed. The crystal structure of the hACE2 receptor and the ligand isovitexin were docked to form a ligand-protein complex following molecular optimization. To determine the isovitexin-hACE2 complex stability, their binding affinity, hydrogen bonding, and hydrophobic interactions were studied. Lastly, the root mean square deviation (RMSD), root mean square fluctuation, solvent accessible surface area, molecular surface area, radius of gyration (Rg), polar surface area, and principal component analysis values were found by simulating the complex with molecular dynamic (MD). Results: The predicted Lethal dose50 for isovitexin was 2.56 mol/kg, with an acceptable maximum tolerated dose and no hepatotoxicity or AMES toxicity. Interactions with the amino acid residues Thr371, Asp367, Glu406, Pro346, His345, Phe274, Tyr515, Glu375, Thr347, Glu402, and His374 of the hACE2 protein were required for the high binding affinity and specificity of isovitexin. Based on what was learned from the MD simulation, the hACE2 receptor-blocking properties of isovitexin were looked at. Conclusions: Isovitexin is a phytochemical with a reasonable bioactivity and safety profile for use in humans, and it can potentially be used as a hACE2-specific therapeutic to inhibit COVID-19 infection.
ABSTRACT
OBJECTIVE: This research aims to study the target specificity of selective bioactive compounds in complexing with the human angiotensin-converting enzyme (hACE2) receptor to impede the severe acute respiratory syndrome coronavirus 2 influx mechanism resulting in cardiac injury and depending on the receptor's active site properties and quantum tunneling. MATERIALS AND METHODS: A library of 120 phytochemical ligands was prepared, from which 5 were selected considering their absorption, distribution, metabolism, and excretion (ADMET) and quantitative structure-activity relationship (QSAR) profiles. The protein active sites and belonging quantum tunnels were defined to conduct supramolecular docking of the aforementioned ligands. The hydrogen bond formation and hydrophobic interactions between the ligand-receptor complexes were studied following the molecular docking steps. A comprehensive molecular dynamic simulation (MDS) was conducted for each of the ligand-receptor complexes to figure out the values - root mean square deviation (RMSD) (Å), root mean square fluctuation (RMSF) (Å), H-bonds, Cα, solvent accessible surface area (SASA) (Å2), molecular surface area (MolSA) (Å2), Rg (nm), and polar surface area (PSA) (Å). Finally, computational programming and algorithms were used to interpret the dynamic simulation outputs into their graphical quantitative forms. RESULTS: ADMET and QSAR profiles revealed that the most active candidates from the library to be used were apigenin, isovitexin, piperolactam A, and quercetin as test ligands, whereas serpentine as the control. Based on the binding affinities of supramolecular docking and the parameters of molecular dynamic simulation, the strength of the test ligands can be classified as isovitexin > quercetin > piperolactam A > apigenin when complexed with the hACE2 receptor. Surprisingly, serpentine showed lower affinity (-8.6 kcal/mol) than that of isovitexin (-9.9 kcal/mol) and quercetin (-8.9 kcal/mol). The MDS analysis revealed all ligands except isovitexin having a value lower than 2.5 Ǻ. All the test ligands exhibited acceptable fluctuation ranges of RMSD (Å), RMSF (Å), H-bonds, Cα, SASA (Å2), MolSA (Å2), Rg (nm), and PSA (Å) values. CONCLUSION: Considering each of the parameters of molecular optimization, docking, and dynamic simulation interventions, all of the test ligands can be suggested as potential targeted drugs in blocking the hACE2 receptor.
ABSTRACT
OBJECTIVE: This study aims for molecular identification of naturally growing Bacillus cereus strain from a unique source, able to survive, and alleviate heavy metals from the nature. MATERIALS AND METHODS: Pure isolate from Murrah buffalo milk was prepared in B. cereus selective Polymyxin pyruvate egg-yolk mannitol-bromothymol blue agar (PEMBA) medium through a cascade of contamination free subcultures. The morphological and biochemical tests were done prior to 16S rRNA gene sequencing for strain identification and further physiological tests. The test strain was inoculated in both solid and suspension culture medium supplemented individually with Cd, Cu, Ag, and Zn to reveal the qualitative and quantitative heavy metal tolerance properties, respectively. Finally, the data collected from the in vitro assessment was statistically analyzed. RESULTS: Molecular analysis revealed that the test strain was B. cereus BF2, which was motile, catalase positive and Gram positive rod. B. cereus BF2 was found significant at 0.3% bile salt tolerance [two-way analysis of variance (ANOVA)-p value is < 0.0001] where, t-test p value is < 0.0002 between Control Group (CG) and TGR-1; p < 0.037 between TGR-1 and 2; p < 0.0014 between CG and TGR-2. Similarly, B. cereus BF2 was significant in pH tolerant up to 8.0 with p < 0.0115 (in scale p < 0.05). The heavy metal tolerance test revealed that the test metals could not stop the growth of B. cereus BF2 even after 24 h of incubation but partially suppressed the growth kinetics for letting into stationary phase. Among the four heavy metals, Cd and Zn showed partial antagonism to the growth of B. cereus BF2. The survivability was highly significant in the medium supplemented with Zn (p < 0.0001) and Ag (p < 0.018). CONCLUSION: Bacillus cereus BF2 can survive in selective heavy metals with metal resistance and biodegradation capacity.