The magnetic isotope effect as a tool for apoptosis modulation in leukemic cells

Lymphocytes from healthy donors and leukemic cells of patients with acute B-lymphoblastic leukemia (BALL-1) and acute myeloid leukemia were exposed to nanoparticles bearing magnetic (Zn-67) and nonmagnetic (total isotope pool) nuclei of zinc. The values of the corresponding magnetic isotope effects determined as the ratio of LD₅₀ magnitudes of preparations with magnetic and nonmagnetic zinc isotopes were 0, 3.5, and 1.5. Morphological studies using confocal and fluorescence microscopy showed apoptotic death of cells with the preparations; as well, there was an increase in the cell aggregation and better aggregation of nanoparticles in the case of ⁶⁷Zn-NP, which resulted in a decrease of cytotoxicity. However the magnetic isotope effect was observed even in the case of aggregation.     

Structural optimization of adaptaquin,a HIF prolyl hydroxylase inhibitor

Russian Chemical Bulletin - The structural optimization of adaptaquin, viz., 7-(4-chlorophenyl)[(3-hydroxypyridin-2-yl)amino]methylquinolin-8-ol, a HIF (hypoxia inducible factor) prolyl hydroxylase...     

Fullerene–Interfaced Porphyrin Ligand in Affinity Chromatography of Membrane Proteins

To purify the mammalian cell membrane porphyrin binding proteins (PBP), an original affinity chromatographic technique is proposed. The method is based on the application of an agarose attached fullerene-porphyrin ligand connected to a polysaccharide gel matrix through the epoxy-cyclohexyl residue interface. A selective PBP-stationary phase coupling has been managed in a single column chromatographic run leading to a complete purification of the 17.6 kDa monomer protein from the rat myocardium mitochondria membranes. A synchronous pH and ionic strength linear gradients were used to separate this protein with a high specific affinity to the porphyrin K related structures from all non-specific sorption retained membrane proteins.     

Antioxidant and antihypoxic properties of neuroprotective drugs

Russian Chemical Bulletin - The screening of the library containing 320 drugs and biologically active compounds was carried out. The library was created for testing potent agents on Rett syndrome...     

Features of Construction of the Fluorescent Microscope for the Study of Epithelial-Mesenchymal Transition of Cells in Vitro

Optics and Spectroscopy - An optical luminescent microscope has been developed to monitor the behavior of tumor cells that were modified by GFP and RFP fluorescent proteins and to monitor the...     

HIF2 ODD-luciferase reporter: the most sensitive assay for HIF prolyl hydroxylase inhibitors

Russian Chemical Bulletin - Reporters expressing fusion proteins of HIF2 and HIF3 C-terminal oxygen degradable domain (ODD) with the firefly luciferase, HIF2 ODD-luc and HIF3 ODD-luc, were...     

Antihypoxic activity of adaptaquin enantiomers

Russian Chemical Bulletin - Adaptaquin, 7-{(4-chlorophenyl)[(3-hydroxypyridin-2-yl)amino]methyl}quinolin-8-ol (1), was identified in our earlier study as a hypoxia-inducible factor (HIF) prolyl...     

Catalytic properties and stability of recombinant tobacco peroxidase with Ile37Met substitution

Tobacco anionic peroxidase (TOP) mutant Ile37Met was produced by site-directed mutagenesis to mimic soybean peroxidase (SBP), in which Met37 is responsible for increased thermal stability. TOP Ile37Met was expressed in E. coli BL21(DE3) CodonPlus in the form of bodies. The expression level of the constructed enzyme was approximately 40% of the total E. coli protein. The enzyme was reactivated into an active and soluble form via a refolding procedure that was earlier developed for wild-type TOP. The substrate specificity, catalytic activity, and thermal stability of TOP Ile37Met were investigated. It was shown that the introduction of the Ile37Met mutation does not increases the stability of the enzyme; on the contrary, it leads to a reduction in the catalytic properties of the enzyme.     

Effect of ketoconazole on the transport and metabolism of drugs in the human liver cell model

The effect of ketoconazole on the biotransformation of amiodarone, rosiglitazone, and cyclophosphamide was studied using the human liver cell model based on differentiated HepaRG spheroids. The concentrations of major metabolites of amiodarone and cyclophosphamide were found to decrease in the presence of ketoconazole, a cytochrome P450 3A4 inhibitor. The concentration of the major metabolite of rosiglitazone, N-desmethyl rosiglitazone, decreased upon the addition of either sulfaphenazole, a cytochrome P450 2C9 inhibitor, or ketoconazole. The rosiglitazone metabolism involves CYP2C9 and CYP2C19. This result is attributable to the inhibitory effect of ketoconazole on p-glycoprotein, which decreases N-desmethyl rosiglitazone concentration in the culture medium. The utilization of the human liver cell model and selective inhibitors of transporters and cytochrome P450 isoforms can serve for standardization of the studies of drug-drug interactions involved in drug transport and metabolism.

     

Metal Ions as Activators of Hypoxia Inducible Factor

Activation of antihypoxic program under the action of a number of transition and heavy metals has been studied using cell-based HIF1 ODD-luc and HRE-luc reporters. It has been demonstrated that Au³⁺, Pb²⁺, Sn²⁺, Hg²⁺ are weak HIF1 ODD-luc activators, likely reflecting their weak competition for the ironbinding site in the active center of HIF prolyl hydroxylase. Metals capable of replacing iron–Mn²⁺, Zn²⁺, Cu²⁺ и Ni²⁺–activate at high submillimolar concentrations, which indicates low permeability of the cell membrane for transition metals. The highest activation is observed for Co²⁺ and Cd²⁺, however, Cd²⁺ is highly toxic even at 10 μM, in contrast to Co²⁺, which activates both reporters without toxicity signs up to 25 μM for 24 h. A significant activation by Co²⁺ is observed already in low micromolar range of concentrations, which can be recommended for use in hypoxia mimicking.