RESULTS: 50% minimum inhibitory concentration with silver-conjugated Hesperidin was achieved with 0.5 μg/ml of Hesperidin conjugated with silver nanoparticles at 1 h. Differential genetic analysis revealed the expression of 122 genes (≥ 2-log FC, P
METHODS: Anti-amoebic effects of phosphanegold(I) thiolates were tested against clinical isolate of A. castellanii belonging to the T4 genotype by employing viability assays, growth inhibition assays, encystation assays, excystation assays, and zymographic assays.
RESULTS: The treatment of A. castellanii with the phosphanegold(I) thiolates tested (i) had no effect on the viability of A. castellanii as determined by Trypan blue exclusion test, (ii) did not affect amoebae growth using PYG growth medium, (iii) did not inhibit cellular differentiation, and (iv) had no effect on the extracellular proteolytic activities of A. castellanii.
CONCLUSION: Being free-living amoeba, A. castellanii is a versatile respirator and possesses respiratory mechanisms that adapt to various aerobic and anaerobic environments to avoid toxic threats and adverse conditions. For the first time, our findings showed that A. castellanii exhibits resistance to the toxic effects of gold compounds and could prove to be an attractive model to study mechanisms of metal resistance in eukaryotic cells.
OBJECTIVE: To study the antiamoebic effects of four novel synthetic dihydropyridine (DHP) compounds against Acanthamoeba castellanii belonging to the T4 genotype. Furthermore, to evaluate their activity against amoeba-mediated host cells cytopathogenicity as well as their cytotoxicity against human cells.
METHODS: Dihydropyridines were synthesized by cyclic dimerization of alkylidene malononitrile derivatives. Four analogues of functionally diverse DHPs were tested against Acanthamoeba castellanii by using amoebicidal, encystation and excystation assays. Moreover, Lactate dehydrogenase assays were carried out to study cytopathogenicity and cytotoxicity against human cells.
RESULTS: These compounds showed significant amoebicidal and cysticidal effects at 50 μM concentration, whereas, two of the DHP derivatives also significantly reduced Acanthamoebamediated host cell cytotoxicity. Moreover, these DHPs were found to have low cytotoxicity against human cells suggesting a good safety profile.
CONCLUSION: The results suggest that DHPs have potential against Acanthamoeba especially against the more resistant cyst stage and can be assessed further for drug development.
RESULTS: A new dimethyl aminopyridine based stabilizing agent named as DMAP-PTA was synthesized and used for stabilization of gold nanoparticles. Gold nanoparticles coated with DMAP-PTA abbreviated as DMAP-PTA-AuNPs were thoroughly characterized by UV-visible, FT-IR spectroscopic methods and transmission electron microscope before biological assay. DMAP-PTA, DMAP-PTA-AuNPs and Pefloxacin were examined for their antibacterial potential against E. coli, and the minimum inhibitory concentration (MIC) was determined to be 300, 200 and 50 µg/mL respectively. Gold nanoparticles conjugation was found to significantly enhance the antibacterial activity of DMAP-PTA as compared to pure compound. Moreover, effects of DMAP-PTA-AuNPs on the antibacterial potential of Pefloxacin was also evaluated by combination therapy of 1:1 mixture of DMAP-PTA-AuNPs and Pefloxacin against E. coli in a wide range of concentrations from 5 to 300 µg/mL. The MIC of Pefloxacin + DMAP-PTA-AuNPs mixture was found to be 25 µg/mL as compared to Pefloxacin alone (50 µg/mL), which clearly indicates that DMAP-PTA-AuNPs increased the potency of Pefloxacin. AFM analysis was also carried out to show morphological changes occur in bacteria before and after treatment of test samples. Furthermore, DMAP-PTA-AuNPs showed high selectivity towards Pefloxacin in spectrophotometric drug recognition studies which offers tremendous potential for analytical applications.
CONCLUSIONS: Gold nanoparticles conjugation was shown to enhance the antibacterial efficacy of DMAP-PTA ligand, while DMAP-PTA-AuNPs also induced synergistic effects on the potency of Pefloxacin against E. coli. DMAP-PTA-AuNPs were also developed as Pefloxacin probes in recognizing the drug in blood and water samples in the presence of other drugs.
METHODS: In this study, various species of vertebrates and invertebrates were procured including Columba livia, Gallus gallus domesticus, Varanus salvator, Cuora kamamora amboinensis, Reticulatus malayanus, Oreochromis mossambicus, Rattus rattus, American bullfrog, Donax sp., Polymesoda coaxans, Tenebrio molitor, Lumbricus terrestris, Blatta lateralis, Grammostola rosea, and Penaeus monodon. Species were dissected and their organ lysates/sera/haemolymph were prepared. Cytotoxicity assays were performed using Prostate Cancer cells (PC3), Henrietta Lacks cervical adenocarcinoma cells (HeLa) and human breast adenocarcinoma cells (MCF7) as well as human keratinized skin cells (Hacat), by measuring lactate dehydrogenase release as an indicator for cell death. Growth inhibition assays were performed to determine the effects on cancer cell proliferation. Liquid Chromatography-Mass Spectrometry (LC-MS/MS) was performed for molecular identification.
RESULTS: The results revealed that body lysates of Polymesoda coaxans demonstrated more than 99% growth inhibition of all cancer cell lines tested but not on normal Hacat cells. More importantly, the serum of M. reticulatus abolished growth and produced cytotoxicity. Hence these samples were subjected to Liquid Chromatography- Mass Spectrometry (LC-MS/MS), which detected 81 small molecules and putatively identified 20 molecules when matched against the METLIN database. Out of 1094 peptides, 21 peptides were identified, while 1074 peptides were categorized as novel peptides. Based on properties such as peptide amino acid composition, binary profile, dipeptide composition and pseudo-amino acid composition, 306 potential peptides were identified.
CONCLUSION: To our knowledge, here for the first time, we report a comprehensive analysis of sera exhibiting cytotoxicity against cancer cell lines tested and identified several molecules using LC-MS/MS.
MATERIALS AND METHODS: Animals were procured and their organ lysates and sera were prepared and tested against Michigan Cancer Foundation-7 breast cancer (MCF-7), prostate cancer (PC3), Henrietta Lacks cervical cancer (HeLa), and normal human keratinocyte cells. Exoskeleton, appendages and hepatopancreas were dissected from the scorpion, whereas liver, lungs, heart, oviduct, gastrointestinal tract, gall bladder, kidneys, eggs and sera were collected from frog and organ lysates/sera were prepared. Growth inhibition assays and cytotoxicity assays were performed.
RESULTS: Appendages, exoskeleton lysates, and hepatopancreas from scorpion exhibited potent growth inhibition, and cytotoxic effects. Furthermore, lungs, liver, gastrointestinal tract, heart, oviduct, kidneys, eggs, and sera from frog displayed growth inhibition and cytotoxic effects.
CONCLUSION: Organ lysates, sera of scorpion, and amphibians possess anti-tumour activities. This is a worthy area of research as the molecular identity of the active molecule(s) together with their mechanism of action will lead to the rational development of novel anticancer agent(s).