Алексеева Анна Сергеевна

Образование

Период обученияСтрана, городУчебное заведениеДополнительная информация
2005–2011 Россия, Москва Московская государственная академия тонкой химической технологии им. М. В. Ломоносова (МИТХТ) Бакалавриат и магистратура

Избранные публикации

  1. Alekseeva A.S., Tretiakova D.S., Chernikov V.P., Utkin Y.N., Molotkovsky J.G., Vodovozova E.L., Boldyrev I.A. (2017). Heterodimeric V. nikolskii phospholipases A2 induce aggregation of the lipid bilayer. Toxicon 133, 169–179 [+]

    We report that the action of the heterodimeric phospholipases A2 (PLA2s) from Vipera nikolskii, which comprises enzymatically active basic subunit and inactive acidic PLA2 homologue, on the lipid bilayer results in the aggregation and stacking of bilayers. These processes are demonstrated using two independent methods (fluorescence spectroscopy and electron microscopy). Aggregation of bilayers is possible because both subunits of the V. nikolskii heterodimer contain a membrane-binding site (also known as IBS). Thus, when the two IBSs bind to the membrane, the heterodimer acts as a connecting agent. Heterodimers induce aggregation of negatively charged bilayers composed of phosphatidylglycerol and do not induce aggregation of neutral bilayers composed of phosphatidylcholine.

    ID:1797
  2. Alekseeva A.S., Moiseeva E.V., Onishchenko N.R., Boldyrev I.A., Singin A.S., Budko A.P., Shprakh Z.S., Molotkovsky J.G., Vodovozova E.L. (2017). Liposomal formulation of a methotrexate lipophilic prodrug: assessment in tumor cells and mouse T-cell leukemic lymphoma. Int J Nanomedicine 12, 3735–3749 [+]

    In a previous study, a formulation of methotrexate (MTX) incorporated in the lipid bilayer of 100-nm liposomes in the form of diglyceride ester (MTX-DG, lipophilic prodrug) was developed. In this study, first, the interactions of MTX-DG liposomes with various human and mouse tumor cell lines were studied using fluorescence techniques. The liposomes composed of egg phosphatidylcholine (PC)/yeast phosphatidylinositol/MTX-DG, 8:1:1 by mol, were labeled with fluorescent analogs of PC and MTX-DG. Carcinoma cells accumulated 5 times more MTX-DG liposomes than the empty liposomes. Studies on inhibitors of liposome uptake and processing by cells demonstrated that the formulation used multiple mechanisms to deliver the prodrug inside the cell. According to the data from the present study, undamaged liposomes fuse with the cell membrane only 1.5-2 hours after binding to the cell surface, and then, the components of liposomal bilayer enter the cell separately. The study on the time course of plasma concentration in mice showed that the area under the curve of MTX generated upon intravenous injection of MTX-DG liposomes exceeded that of intact MTX 2.5-fold. These data suggested the advantage of using liposomal formulation to treat systemic manifestation of hematological malignancies. Indeed, the administration of MTX-DG liposomes to recipient mice bearing T-cell leukemic lymphoma using a dose-sparing regimen resulted in lower toxicity and retarded lymphoma growth rate as compared with MTX.

    ID:1796
  3. Алексеева А.С., Третьякова Д.С., Мельникова Д.Н., Молотковский Юл.Г., Болдырев И.А. (2016). Новый флуоресцентный мембранный зонд (2,3;5,6 бисциклогексил)bodipy меченный фосфатидилхолн. Биоорг. хим. 42 (3), 339–344 [+]

    Новый мембранный зонд бисциклогексил BODIPY (BCHB) меченный фосфатидилхолин структурно очень близок в 1,3,5,7 тетраметил BODIPY (TMB) меченному фосфатидилхолину и синтезируется по аналогичной схеме. Системы сопряженных связей BCHB и TMB формально идентичны, однако спектральные характеристики BCHB заметно отличаются, что делают BCHB хорошим акцептором фёрстеровского резонансного переноса (FRET) для TMB. Показано, что FRET пара фосфатидилхолинов на основе BCHB и TMB является перспективным инструментом для исследования мембранных систем, например, межмембранного липидного переноса.
     

    ID:1498
  4. Alekseeva A., Kapkaeva M., Shcheglovitova O., Boldyrev I., Pazynina G., Bovin N., Vodovozova E. (2015). Interactions of antitumour Sialyl Lewis X liposomes with vascular endothelial cells. Biochim. Biophys. Acta 1848 (5), 1099–1110 [+]

    Recently, we showed that tetrasaccharide selectin ligand SiaLe(X) provided targeted delivery of liposomes loaded in the bilayer with melphalan lipophilic prodrug to tumour endothelium followed by severe injury of tumour vessels in a Lewis lung carcinoma model. Here, we study the impact of SiaLe(X) ligand on the interactions of liposomes with human umbilical vein endothelial cells (HUVEC) using flow cytometry, spectrofluorimetry and confocal microscopy. Liposomes composed of egg phosphatidylcholine/yeast phosphatidylinositol/1,2-dioleoyl glycerol ester of melphalan, 8:1:1, by mol, and varying percentages of lipophilic SiaLe(X) conjugate were labelled with BODIPY-phosphatidylcholine. The increase in SiaLe(X) content in liposomes led to a proportional increase in their uptake by cytokine-activated cells as opposed to non-activated HUVEC: for 10% SiaLe(X) liposomes, binding avidity and overall accumulation increased 14- and 6-fold, respectively. The early stages of intracellular traffic of targeted liposomes in the activated cells were monitored by co-localisation with the trackers of organelles. Endocytosis of SiaLe(X) liposomes occurred mostly via clathrin-independent pathways, which does not contradict the available literature data on E-selectin localisation in the plasma membrane. Using dual fluorescence labelling, with rhodamine-labelled phospholipid and calcein encapsulated at self-quenching concentrations, we found that SiaLe(X) liposomes undergo rapid (within minutes) internalisation by activated HUVEC accompanied by the disruption of liposomes; non-activated cells consumed a negligible dose of liposomes during at least 1.5h. Our data evidence the selective effect of SiaLe(X) formulations on activated endothelial cells and indicate their potential for intracellular delivery of melphalan lipophilic prodrug.

    ID:1242
  5. Alekseeva A.S., Korotaeva A.A., Samoilova E.V., Volynsky P.E., Vodovozova E.L., Boldyrev I.A. (2014). Secretory phospholipase A2 activity in blood serum: The challenge to sense. Biochem. Biophys. Res. Commun. 454 (1), 178–182 [+]

    Excess levels of secretory phospholipase A2 (sPLA2) is known to contribute to several inflammatory diseases including vascular inflammation correlating with coronary events in coronary artery disease. Thus a method to monitor sPLA2 activity in blood serum is urgently needed. Such method is still a challenge since existing fluorescent probes do not allow to monitor sPLA2 activity directly in blood serum. Here we analyze and overcome barriers in sPLA2 sensing methodology and report a fluorescent probe and a kinetic model of its hydrolysis by sPLA2. New probe is designed with a fluorophore and a quencher not interfering binding to the enzyme. At the same time phospholipid matrix bearing the probe promotes efficient initial quenching of the fluorophore. Kinetic model of probe hydrolysis takes into account signal change due to the side processes. The probe and the kinetic model applied together prove the concept that the activity of sPLA can be measured directly in blood serum.

    ID:1124
  6. Vlasenko Yu.V., Alekseeva A.S., Vodovozova E.L. (2014). Synthesis of a Fluorescent Analogue of Methotrexate Lipophilic Prodrug. Russ. J. Bioorgan. Chem. 40 (1), 114–117 [+]
    A fluorescent analogue of the lipophilic prodrug of antitumor agent methotrexate has been synthesized. The conjugate consists of a residue of rac 1 [13 (Me 4 BODIPY 8)tridecanoyl] 2 oleoylglycerol connected to methotrexate by an ester bond via β Ala N carbonylmethylene linker (Me 4 BODIPY 8 stands for 4,4 difluoro 1,3,5,7 tetramethyl 4 bora 3a,4a diaza s indacene 8 yl). The probe is designed for incor poration in the membrane of the liposomal vehicle to study a mechanism of interaction with tumor cells and intracellular traffic.
    ID:1001
  7. Ivanova E.A., Maslov M.A., Kabilova T.O., Puchkov P.A., Alekseeva A.S., Boldyrev I.A., Vlassov V.V., Serebrennikova G.A., Morozova N.G., Zenkova M.A. (2013). Structure-transfection activity relationships in a series of novel cationic lipids with heterocyclic head-groups. Org. Biomol. Chem. 11, 7164–7178 [+]

    Cationic liposomes are promising candidates for the delivery of various therapeutic nucleic acids. Here, we report a convenient synthesis of carbamate-type cationic lipids with various hydrophobic domains (tetradecanol, dialkylglycerol, cholesterol) and positively charged head-groups (pyridinium, N-methylimidazolium, N-methylmorpholinium) and data on the structure-transfection activity relationships. It was found that single-chain lipids possess high surface activity, which correlates with high cytotoxicity due to their ability to disrupt the cellular membrane by combined hydrophobic and electrostatic interactions. Liposomes containing these lipids also display high cytotoxicity with respect to all cell lines. Irrespective of chemical structures, all cationic lipids form liposomes with similar sizes and surface potentials. The characteristics of complexes composed of cationic liposomes and nucleic acids depend mostly on the type of nucleic acid and P/N ratios. In the case of oligodeoxyribonucleotide delivery, the transfection activity depends on the type of cationic head-group regardless of the type of hydrophobic domain: all types of cationic liposomes mediate efficient oligonucleotide transfer into 80-90% of the eukaryotic cells, and liposomes based on lipids with N-methylmorpholinium cationic head-group display the highest transfection activity. In the case of plasmid DNA and siRNA, the type of hydrophobic domain determines the transfection activity: liposomes composed of cholesterol-based lipids were the most efficient in DNA transfer, while liposomes containing glycerol-based lipids exhibited reasonable activity in siRNA delivery under serum-free conditions.

    ID:873
  8. Alekseeva A.S., Maslov M.A., Antipova N.V., Boldyrev I.A. (2011). Comparison of two lipid/DNA complexes of equal composition and different morphology. Colloids Surf B Biointerfaces 88 (1), 512–6 [+]

    Two types of complexes were prepared from a cationic cholesterol derivative, dioleoylphos-phatidylcholine and DNA. Depending on the preparation procedure complexes were either dense snarls of lipid covered DNA (type A) or multilayer liposomes with DNA between layers (type B). The transfection efficiency of the snarl-shaped complexes was low but positive. The transfection efficiency of the liposome-shaped complexes was zero, while DNA release upon their interaction with anionic liposomes was 1.7 times higher. The differences in transfection efficacy and DNA release could not be ascribed to the difference in resistance of complexes to decomposition upon interaction with anionic liposomes or intracellular environment since the lipid composition of complexes is the same. Instead the complexes in which lipoplex phase is more continuous (type A) should require more anionic lipids or more time within a cell for complete decomposition. Prolonged life time should lead to the higher probability of DNA expression.

    ID:524