In vitro and in silico binding studies of phytochemical isochroman with calf thymus DNA using multi-spectroscopic and computational modelling techniques

Insight into the interaction of isochroman with bovine serum albumin: extensive experimental and computational investigations

The way therapeutic compounds interact with serum protein provides valuable information on their pharmacokinetics, toxicity, effectiveness, and even their structural-related information. Isochroman (IC) is a phytochemical compound obtained from the leaves of Olea europea plant. The derivatives of IC have various pharmacological properties including antidepressants, antihistamines, antiinflammation, anticonvulsants, appetite depressants, etc. The binding of small molecules to bovine serum albumin (BSA) is useful to ensure their efficacy. Thus, in this study, we have found out the binding mode of IC with BSA using several spectroscopic and in silico studies. UV and fluorescence spectroscopy suggested the complex formation between IC and BSA with a binding constant of 103 M-1. IC resulted in fluorescence quenching in BSA through static mechanism. The microenvironmental and conformational changes in BSA were confirmed using synchronous and three-dimensional studies. Site marker experiment revealed the IC binding in site-III of BSA. The influence of vitamins, metals and β-cyclodextrin (β-CD) on binding constant of IC-BSA complex was also examined. Circular dichroism spectra showed that α-helical of BSA decreased upon interaction with IC. Computational and experimental results were complimentary with one another and assisted in determining the binding sites, nature of bonds and amino acids included in the IC-BSA complex formation.Communicated by Ramaswamy H. Sarma.

Phytocompounds screening of Nigella sativa in terms of human cancer by targeting sphingosine kinase-1 and pyruvate kinase-M2: a study based on in silico analysis

Cancer is a multifactorial disease that can cause morbidity and mortality in humans. An altered gene expression in cancer leads to a change in the overall activity of the human cell. Overexpression of cancer protein may give a piece of wide information about the specific type of tumor. Sphingosine kinase-1 (SK-1) is a metabolic enzyme that is mainly overexpressed in several types of cancer and other inflammatory diseases. Similarly, pyruvate kinase-M2 (PK-M2) is an important oncogenic ATP-producing glycolytic enzyme that is upregulated in most cancer cells. The phytocompound of medicinal plants such as Nigella sativa contains a variety of micronutrients that inhibit the proliferation and activity of tumor cells. In this study, the role of phytocompounds in combating cancer was studied against the model kinase proteins, that is, PK-M2 and SK-1. In silico tool like the PASS-Way2Drug server was used to predict the anticancer properties of phytocompounds. Moreover, the CLC-Pred web server provided the cytotoxicity prediction of chemical compounds against several human cancer cell lines. The pharmacokinetics and toxicity profiles were predicted by the SwissADME and pkCSM software. The binding energies were obtained by molecular docking to confirm the intermolecular interaction of selected phytocompounds with proteins. Consequently, molecular dynamics (MD) simulation confirmed the stability, conformational changes, and dynamic behavior of the kinase proteins complexed with the lead phytocompounds, that is, epicatechin, apigenin, and kaempferol.Communicated by Ramaswamy H. Sarma.

Preparation of nanoformulation of 5-fluorouracil to improve anticancer efficacy: integrated spectroscopic, docking, and MD simulation approaches

Nanoformulations (NFs) can be used as a novel drug delivery system to treat all cancer types. One of the major drawbacks of conventional anticancer drugs is that they have poor specificity and higher toxicity towards normal cells. 5-fluorouracil (5-FU) is a well-studied anticancer drug that has a significant role in various cancers, specifically colorectal cancer therapy. This study was performed to determine the functional groups, particle size, surface charge, heterogeneity, and stability of the NF. The NFs of 5-FU were prepared through the ultrasonication technique by increasing the surfactant (Tween-80) concentrations. Among all three NFs, nanoformulated 5-FU (n5-FU) showed the most effective particle size (10.72 nm) with a zeta potential of (-4.57 mV). The cytotoxicity and apoptosis profiles confirmed that n5-FU enhanced the anticancer effect of the pure drug in HCT-116 cells, as evident from MTT assay, fluorescence microscopy, and FACS analysis. In HCT-116 cells, the IC50 values of pure and n5-FU were obtained as 41.3 μM and 18.8 μM, respectively, indicating that n5-FU was more effective against the cancer cell line. The cellular uptake study was performed to check the intake of NF in cancer cells. However, the microtubule-affinity regulating kinase-4 (MARK-4), a cancer-target protein, was purified to study the inhibition and interaction studies. The inhibition assay confirmed the inhibitory potential of 5-FU against MARK-4 protein. the multi-spectroscopic, molecular docking and MD simulation studies were performed to analyse the conformational changes, binding studies, intermolecular interactions, and stability of MARK-4 protein upon binding 5-FU. This demonstrates that NF can enhance the effectiveness of anticancer drugs.Communicated by Ramaswamy H. Sarma.

Flubendiamide induced genetic and cellular damages directly influence the life cycle of the oriental leaf worm, Spodoptera litura

Indiscriminate uses of insecticide greatly damage the environment as well as non-target organisms. Thus, multiple levels of bioassays can help better management of our environment. Flubendiamide is a phthalic acid diamide insecticide that ceases the function of insect muscle leading to paralysis and death. Here, we aimed to explore the effects of Flubendiamide on the life cycle of Spodoptera litura vis-a-vis the mode of action. Fourth instar larvae of the same age (120 ± 2 h) and size were fed with different concentrations (20-80 μg/mL) of Flubendiamide for 12-72 h. We performed a pharmacokinetics study, different biochemical assays, p450, Ecdysone receptor (EcR) and other genes expression analyses by Real-Time PCR and gross damages by Dye exclusion assay and histopathology. Our results demonstrate that the mean concentration of Flubendiamide after 48 h is 9.907 μg/mL and (i) altered the molting, metamorphosis, and reproduction at 80 μg/mL (24 h) (ii) increases all oxidative stress parameters (ROS/RNS, MDA, 8OHdG), decreases oxidative defense mechanisms (SOD, CAT, GST) at 80 μg/mL (48 h) and p450 in a time and concentration-dependent manner, (iii) activates CncC/Maf apoptotic pathways at 80 μg/mL concentration at 24 h while the expression declined from 48 h onwards, (iii) downregulates the EcR expression in a time and concentration-dependent manner, which might be responsible for disturbed molting, metamorphosis, and reproduction, and (iv) increase the expression of apoptotic genes (Caspase 1, -3, and - 5), in time and concentration-dependent manner causing gross morphological and histological damages. In conclusion, indiscriminate use of this insecticide can affect the ecosystem and have the capacity to cause multiple hazardous effects on experimental organisms. Thus, it warrants further investigations to improve and optimize the integrated pest management packages, including Flubendiamide for better management.