In this research, we report the size-controlled synthesis and surface-functionalization of magnetite with the natural antioxidant gallic acid (GA) as a ligand, using in situ and post-synthesis methods. GA functionalization provided narrow size distribution, with an average particle size of 5 and 8 nm for in situ synthesis of gallic acid functionalized magnetite IONP@GA1 and IONP@GA2, respectively, which are ultra-small particles as compared to unfunctionalized magnetite (IONP) and post functionalized magnetite IONP@GA3 with average size of 10 and 11 nm respectively. All the IONPs@GA samples were found hydrophilic with stable aggregation state. Prior to commencement of experimental lab work, PASS software was used to predict the biological activities of GA and it is found that experimental antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and antimicrobial studies using well diffusion method are in good agreement with the simulated results. Furthermore, the half maximal inhibitory concentration (IC50) values of DPPH antioxidant assay revealed a 2–4 fold decrease as compared to unfunctionalized IONP. In addition to antioxidant activity, all the three IONP@GA proved outstanding antimicrobial activity while testing on different bacterial and fungal strains. The results collectively indicate the successful fabrication of novel antioxidant, antimicrobial IONP@GA composite, which are magnetically separable, efficient, and low cost, with potential applications in polymers, cosmetics, and biomedical and food industries.
4 December 2013 in BMC Complementary and Alternative Medicine
Background: Hepatocellular carcinoma is a common type of tumour worldwide with a high mortality rate and with low response to current cytotoxic and chemotherapeutic drugs. The prediction of activity spectra for the substances (PASS) software, which predicted that more than 300 pharmacological effects, biological and biochemical mechanisms based on the structural formula of the substance was efficiently used in this study to reveal new multitalented actions forVitex negundo(VN) constituents.Methods: Experimental studies based on antioxidant and antiproliferative assays verified the predictions obtained by the PASS-predicted design strategy. Antioxidant activity of VN extract was studied using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and Ferric reducing or antioxidant power (FRAP) assays. The antiproliferative activity of VN extract against WRL68 and HepG2 was investigated based on methylthiazol tetrazolium (MTT) spectrophotometric assay.Results: VN extract showed 79.43% inhibition of DPPH stable radical with IC5013.31 ± 0.18 μg/ml. This inhibition was too closed to butylated hydroxyl toluene (BHT) 82.53% (IC5013.8 ± 0.14) and gallic acid 89.51% (IC503.1 ± 0.08). VN extract exhibited the strongest free radical scavenging power compared with two commercial antioxidants, BHT and ascorbic acid. VN increased the activities of antioxidant enzymes in normal embryonic liver cells (WRL68) including, superoxide dismutase (SOD) and glutathione peroxidase (GPX) compared with to H2O2group. The ethanolic extract of VN showed cytotoxicity to HepG2 cells in a dose and time-dependent manner with IC5066.46 μg/ml, 57.36 μg/ml and 65.12 μg/ml at 24, 48, and 72-hours incubation respectively, with no sensitivity in WRL68 cells. This was associated with significant elevation in lactate dehydrogenase (LDH) release in HepG2 cells. In addition, the activation of caspase-3 enzyme suggesting that the observed cytotoxicity was mediated via an intrinsic apoptosis pathway.Conclusions: PASS-predicted plant activity could efficiently help in selecting a promising pharmaceutical leads with high accuracy and required antioxidant and antiproliferative properties. This is the first report on PASS-predicted VN activity.
A computer-aided predictions of antioxidant activities were performed with the Prediction Activity Spectra of Substances (PASS) program. Antioxidant activity of compounds 1, 3, 4 and 5 were studied using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and lipid peroxidation assays to verify the predictions obtained by the PASS program. Compounds 3 and 5 showed more inhibition of DPPH stable free radical at 10−4 M than the well-known standard antioxidant, butylated hydroxytoluene (BHT). Compound 5 exhibited promising invitro inhibition of Fe2+-induced lipid peroxidation of the essential egg yolk as a lipid-rich medium(83.99%, IC50 16.07 ± 3.51 µM/mL) compared to a-tocopherol (a-TOH, 84.6%, IC50 5.6 ± 1.09 µM/mL). The parameters for drug-likeness of these BHT analogues were also evaluated according to the Lipinski’s “rule-of-five” (RO5). All the BHT analogues were found to violate one of the Lipinski’s parameters (LogP > 5), even though they have been found to be soluble in protic solvents. The predictive polar surface area (PSA) and absorption percent (% ABS) data allow us to conclude that they could have a good capacity for penetrating cell membranes. Therefore, one can propose these new multipotent antioxidants (MPAOs) as potential antioxidants for tackling oxidative stress and lipid peroxidation processes.
1 November 2014 in European Journal of Medicinal Chemistry
Background: Oxidative stress due to abnormal induction of reactive oxygen species (ROS) molecules is believed to be involved in the etiology of many diseases. Evidences suggest that ROS is involved in nephrotoxicity through frequent exposure to industrial toxic agents such as thioacetamide (TAA). The current investigation was designed to explore the possible protective effects of the leaves of Vitex negundo(VN) extract against TAA-induced nephrotoxicity in rats. Methods: Twenty four Sprague Dawley rats were divided into four groups: (A) Normal control, (B) TAA (0.03% w/v in drinking water), (C) VN100 (VN 100 mg/kg + TAA) and (D) VN300 (VN 300 mg/kg + TAA). Blood urea and serum creatinine levels were measured,supraoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) levels of renal tissue were assayed. Histopathological analysis together with the oxidative stress nicotinamide adenine dinucleotide phosphate (NADPH) oxidase p22phox in kidney sections were examined in all experimental groups. Results: Blood urea and serum creatinine levels were increased in TAA group as a result of the nephrotoxicity compared to the VN100 and VN300 groups where, the levels were significantly decreased (p < 0.05). Renal MDA level was significantly decreased (p < 0.05) in the VN-treated groups with increased CAT and SOD activities compared to the TAA group. Light microscopic examination of renal tissues stained by H&E stain and Masson’s Trichrome for TAA-treated groups revealed severe histopathological changes, whereas specimens obtained from VN-treated groups showed only mild changes. These findings were supported by immunohistochemical results. Conclusions: VN extract acts as a natural potent antioxidant to prevent ongoing TAA-induced nephrotoxicity in rats, both biochemically and morphologically.