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Biomedical subjects

N I Larionova

Publications and source records attributed to N I Larionova.

At least 19 recordsLinked to original sources
PubMed2006

Interaction of native Bowman-Birk soybean protease inhibitor and its hydrophobized derivative with multilamellar vesicles of soybean phospholipids.

The interaction of native Bowman-Birk soybean protease inhibitor (BBI) and its hydrophobized derivative with multilamellar vesicles of various soybean phospholipids was investigated. Decrease in pH and introduction of negatively charged components to the lipid mixture increased BBI content in the protein-lipid complex. This suggests a contribution of electrostatic forces in the protein-lipid interaction. Protein hydrophobization insignificantly influenced BBI binding to lipids. In the complex with lipids, both proteins (BBI and its hydrophobized derivative) retained high anti-chymotrypsin activity (75-100%), which was not influenced by the presence of the ionic detergent sodium deoxycholate.

Deoxycholic Acid↗
PubMed2006

Interaction between human alpha2-macroglobulin and duodenase, a serine proteinase with dual specificity.

Interaction between a serine proteinase from bovine duodenum and human serum alpha(2)-macroglobulin (alpha(2)-MG) was studied. alpha(2)-MG is established to be one of the most effective duodenase inhibitors. The enzyme is completely inhibited in less than 30 sec at equimolar ratio of the inhibitor and enzyme (concentration 2 x 10(-8) M). Under identical conditions, the rate of duodenase association with alpha(2)-MG is at least 2.5-fold higher than the rate of chymotrypsin association with this inhibitor. The interaction with duodenase results in proteolysis of the inhibitor subunit in the "bait region". Similarly to other proteases, duodenase in the complex with alpha(2)-MG retains the intact catalytic apparatus and ability to hydrolyze some small substrates. But the duodenase-inhibitor complex is fully inactive to proteins (bovine serum albumin). The stoichiometry of the enzyme interaction with the inhibitor is 2 : 1 (mol/mol). Based on the association rate constant and the termination time of the duodenase and alpha(2)-MG in vivo association, alpha(2)-MG is suggested to be a physiological regulator of the enzyme.

Animals↗
PubMed2004

Cationic inhibitors of serine proteinases from buckwheat seeds: study of their interaction with exogenous proteinases.

The inhibition of exogenous serine proteinases of different origin by cationic protease inhibitors BWI-1c, -2c, -3c, and -4c from buckwheat (Fagopyrum esculentum Moench) seeds has been studied. High efficiency of the inhibitors in binding bovine trypsin and chymotrypsin as well as their broad antiprotease effect, including inhibition of proteinases secreted by fungi and bacteria, has been demonstrated. According to the data obtained, it is proposed that cationic inhibitors from buckwheat seeds may participate in the defense of plants against fungal and bacterial infection.

Animals↗
PubMed2004

Interaction of polymer aggregates based on stearoyl-poly-N-vinylpyrrolidone with blood components.

Stearoyl-poly-N-vinylpyrrolidone (PVP-stear) of various molecular weights (M(n) = 1500-5500) self-assemble in aqueous medium. Particles prepared from PVP-stear were characterized in terms of shape and size distribution, and the mechanical stability of the particles was studied. The interaction of PVP-stear and its aggregates with blood components was investigated. Aggregates formed by the polymers with M(n) = 1500-3500 in the presence of human serum are stable. The direct lytic action of PVP-stear preparations was studied using sheep and human erythrocytes. The influence of PVP-stear aggregates on the activation of complement system both on classical and alternative pathways was examined. The aggregates prepared from PVP-stear of various molecular weights had no effect on the activation of the complement system.

Animals↗
PubMed2004

Fabrication and characterization of polyelectrolyte microparticles with protein.

The incorporation of proteins into microparticles fabricated by layer-by-layer adsorption of oppositely charged polyelectrolytes (dextran sulfate and protamine) on protein microaggregates was studied. Microaggregates with insulin were prepared by two different techniques: 1) formation of insoluble polyelectrolyte complex consisting of insulin and dextran sulfate (aggregate size of 7-20 micro m), or 2) salting out of insulin from solution by sodium chloride (aggregate size of 5-13 micro m). Microparticles varying in the number of cycles (from 1 to 8) of polyelectrolyte adsorption on protein aggregates were examined and compared. Morphology of the microparticles was studied by scanning electron and optical microscopy. It was shown that polyelectrolyte microparticles retained the shape and dimensions of the initial protein aggregates used as a template. Ultrasonication of microparticles obtained using salted out protein aggregates resulted in the formation of stable nanoparticles (100-200 nm). Regulation of protein release from the microparticles of both types by varying the number of polyelectrolyte adsorption cycles and pH of the medium was demonstrated. Insulin not bound to polyelectrolytes was released from the microparticles at pH values between 6 and 8, which corresponds to the pH of the human small intestine and ileum.

Adsorption↗
PubMed2004

Encapsulation of catalase in polyelectrolyte microspheres composed of melamine formaldehyde, dextran sulfate, and protamine.

Immobilization of catalase (molecular weight 240,000 daltons) in polyelectrolyte microspheres was studied. The microspheres were obtained by alternating adsorption of dextran sulfate and protamine on commercially available melamine formaldehyde cores followed by the core hydrolysis at pH 1.7. As the interior of the microspheres was filled with homogeneous matrix, the catalase distribution inside the microspheres was uniform. The quantity of entrapped catalase was dependent on the initial concentration of the enzyme and pH of solution, and the peak value was 10(8)-10(9) molecules per microsphere. It was demonstrated that catalase was entrapped in the microspheres via electrostatic and hydrophobic interactions. The catalase activity inside the microspheres increased as the quantity of enzyme decreased, which was due to the switch between diffusion and kinetic regimes of the enzymatic reaction. The microspheres could be applied for separation and concentration of high molecular weight proteins.

Catalase↗
PubMed2003

Effect of membranotropic and mucoadhesive formulations of protein proteinase inhibitors on bovine herpes virus-1 reproduction.

The lipidized derivatives of Bowman-Birk soybean protease inhibitor (BBI) containing one to three oleoyl groups were synthesized and characterized. The (ole)(1)- and (ole)(2)BBI were demonstrated to have 200- and 100-fold higher uptake into Caco-2 cell monolayers compared to native BBI. The acylated BBI had increased affinity to elastase-like proteases. Aprotinin-loaded starch/bovine serum albumin microcapsules were prepared using interfacial cross-linking with terephthaloyl chloride and characterized for their morphology, size and release of the inhibitor. Various formulations of protein proteinase inhibitors were tested for their influence on BHV-1 reproduction in cell cultures. Native aprotinin possessed palpable dose-dependent effect inhibiting the virus reproduction up to 4.0 lg (10,000-fold). The bioadhesive, biodegradable aprotinin-loaded microcapsules were the most effective decreasing virus infectious titer up to 4.0 lg and delaying the cytopathic effect up to 144 h in lesser doses of aprotinin. The lipophilic derivative (ole)(1)BBI was shown to exhibit effective inhibition (>100-fold) of BHV-1 reproduction unlike native BBI.

Adhesiveness↗
PubMed2003

Inclusion of proteins into polyelectrolyte microparticles by alternative adsorption of polyelectrolytes on protein aggregates.

A new method of protein immobilization into polyelectrolyte microparticles by alternative adsorption of the oppositely charged polyelectrolytes on the aggregates obtained by salting out of protein is proposed. The model protein alpha-chymotrypsin (ChT) was included in the polyelectrolyte microparticles obtained by various number of polyelectrolyte adsorption steps (from 1 to 11). The main parameters of ChT inclusion into microparticles were calculated. Scanning electron and optical microscopy were used for characterization of morphology and determination of particle size which was from 1 to 10 micro m in most cases. It was shown that the size and shape of protein-containing particles and protein aggregates used as a matrix were similar. Change in ChT enzymatic activity during entrapment into polyelectrolyte particles and activity of released protein were studied. The effect of pH on release of incorporated proteins was investigated; it was shown that change in pH and the number of polyelectrolyte adsorption steps allows protein release to be manipulated.

Adsorption↗
PubMed2003

Self-assembling systems based on amphiphilic poly-N-vinylpyrrolidone and their interaction with model proteins.

Polymeric particles formed by stearoyl-poly-N-vinylpyrrolidone (PVP-stear) of M(n) = 2600 were obtained in aqueous solution, and their shape and size distribution were characterized. The size of the particles was shown to decrease with an increase in the ionic strength of the solution. Interaction of PVP-stear and its aggregates with model proteins (Bowman-Birk soybean proteinase inhibitor (BBI) and its hydrophobized derivatives) was studied. The possibility of inclusion of both native BBI and oleoylic derivative of BBI in the PVP-stear polymeric aggregates was investigated. It was established that polymeric particles with a diameter of 30 nm formed under certain concentration ratios between PVP-stear and poorly soluble dioleoyl BBI are capable of solubilization of dioleoyl BBI as well as prevention of its inactivation at low pH values.

Chromatography, Gel↗
PubMed2002

Study of antiproteinase activity of acylated derivatives of Bowman-Birk soybean proteinase inhibitor.

The effect of acylation of Bowman-Birk soybean proteinase inhibitor (BBI) by derivatives of various unsaturated fatty acids on inhibition of trypsin, alpha-chymotrypsin, and human leukocyte elastase was investigated. Inhibition (K(i)) and kinetic (k(ass), k(diss)) constants of interaction between proteases and acylated BBI derivatives were determined. For mono-, di-, and triacylated BBI derivatives, insertion of two oleic residues into the BBI molecule was demonstrated to be more potent for exhibiting antiproteinase activity.

Acylation↗
PubMed2001

Encapsulation of proteins by layer-by-layer adsorption of polyelectrolytes onto protein aggregates: factors regulating the protein release.

A novel method of protein encapsulation is proposed. Preformed protein aggregates are covered with polyelectrolyte layers by means of layer-by-layer adsorption. The polyelectrolyte membrane prevents protein leakage out of the capsule. Using chymotrypsin as a model enzyme the capsule wall selective permeability was demonstrated for substrates and inhibitors of different molecular weight and solubility.

Adsorption↗
PubMed2001

Acylation of Bowman-Birk soybean proteinase inhibitor by unsaturated fatty acid derivatives.

A procedure was developed for acylation of Bowman-Birk soybean proteinase inhibitor (BBI) by N-hydroxysuccinimide esters of oleic, linoleic, and alpha-linolenic acids in a dimethyl sulfoxide-dioxane-pyridine mixture. BBI derivatives containing two acylated amino groups were prepared with high yield. The use of the reversible modifier citraconic anhydride in the first stage of synthesis permitted the synthesis of hydrophobized BBI derivatives retaining high antitrypsin and antichymotrypsin activities. It was found that the insertion of two long-chain moieties in the BBI molecule decreases its thermostability.

Acylation↗
PubMed2001

Soybean bowman--birk inhibitor conjugates with clinical dextran. synthesis and antiproteolytic activity.

Conjugates of the classical soybean Bowman-Birk inhibitor (BBI) with clinical dextran were synthesized. Clinical dextran was preliminarily oxidized with periodate to dialdehydedextran (DAD). The effect of the degree of oxidation of DAD on coupling of the inhibitor was evaluated. The binding of the protein was shown to increase with increasing degree of DAD oxidation (5, 10, 20%). Total coupling of the inhibitor occurred when the degree of oxidation of the dextran was 20%. The BBI-DAD (20%) conjugate contained 13% protein with BBI/DAD molar ratio 1 : 1. The conjugates retained the ability to inhibit trypsin (Ki = 0.2-0.3 nM) and alpha-chymotrypsin (Ki = 15-30 nM). Thus, the coupling of BBI with the polymeric carrier caused practically no decrease in the antiproteolytic activity of the inhibitor.

Alkylation↗
PubMed2001

Interaction between duodenase and alpha1-proteinase inhibitor.

The interaction between duodenase, a newly recognized serine proteinase belonging to the small group of Janus-faced proteinases, and alpha1-proteinase inhibitor (alpha1-PI) from human serum was investigated. The stoichiometry of the inhibition was 1.2 mol/mol. The presence of a stable enzyme-inhibitor complex was shown by SDS-PAGE. The mechanism of interaction between duodenase and alpha1-PI was shown to be of the suicide type. The equilibrium and inhibition constants are 13 +/- 3 nM and (1.9 +/- 0.3).105 M-1.sec-1, respectively. Based on the association rate constant of the enzyme-inhibitor complex and localization of duodenase and alpha1-PI in identical compartments, alpha1-PI is suggested to be a duodenase inhibitor in vivo.

Electrophoresis, Polyacrylamide Gel↗
PubMed2001

Complexing of basic pancreatic proteinase inhibitor with soybean phospholipid multilamellar vesicles.

The formation of complexes of basic pancreatic proteinase inhibitor (BPTI) with multilamellar vesicles (MLV) from six preparations of soybean phospholipids of various composition was studied. When BPTI, a non-membrane protein, interacts with MLV, the vesicles aggregate, forming a precipitate of protein-lipid complexes. The BPTI content in the protein-lipid complexes increases with decreasing pH of the medium and on addition of negatively charged components into the lipid mixture. The protein-induced aggregation of the phospholipid vesicles is suggested to be mainly determined by electrostatic forces. The antiproteinase activity of BPTI in the complexes was rather low but increased up to 70% of the initial activity on addition of an ionic detergent (sodium deoxycholate).

Aprotinin↗
PubMed2001

Immunoconjugates of soybean Bowman-Birk protease inhibitor as targeted antitumor polymeric agents.

To enhance the antitumor potential of soybean Bowman-Birk inhibitor (BBI), the conjugate of BBI with an antibody via a macromolecular carrier was prepared. Clinical dextran (D) was used as a biocompatible biodegradable carrier for co-immobilization of BBI and antibody. A model immunoglobulin isolated from sheep serum (sIgG), raised against human IgM was utilized to develop the procedure of immunoconjugate synthesis. The molar ratio of the ingredients in the conjugate was the following BBI:D:sIgG=9:1:1. Comparison of the dose response curves for the native sIgG and the BBI-D-sIgG conjugate indicated that sIgG completely retained its specific activity (>90%) after modification with dextran. The determination of the Ki values for chymotrypsin interaction with the native BBI and the BBI-D-sIgG conjugate indicated high anti-chymotrypsin activity. In the next step, the monoclonal antibody (ICO 25 MAb) against the mucin-like human epithelial membrane antigen was used for conjugation as it is the most universal vector for targeting different agents to human tumors of epithelial origin. The influence of conjugation on the specificity of the Mab reaction with its antigen was studied. The conjugated MAb reacted with tumor cells of different epithelial genesis (breast, lung, gastric, ovarian and uterus tumors), but did not react with tumor cells of non-epithelial origin. It was shown that BBI-D-ICO 25 MAb conjugate has almost the same immunohistochemical activity as non-conjugated MAb. These results demonstrated the feasibility of exploiting the activities of covalently bound BBI and ICO 25 MAb for anticarcinogenic agent targeting.

Animals↗
PubMed2000

Isolation and characterization of soybean Bowman-Birk inhibitor from different sources.

A chromatographic procedure for isolation of different isoforms of Bowman--Birk soybean trypsin inhibitors was developed. The number of isoforms was shown to depend on soybean cultivar. The amount of the classical Bowman--Birk inhibitor (BBI) in different soybean cultivars, commercial flour, and processing products was analyzed. BBI reaches its highest concentration in freshly milled seeds. Storage conditions optimum for preservation of maximum inhibitory activity in soybean raw material were developed. The use of indirect enzyme immunoassay for BBI detection during its isolation from different sources was demonstrated.

Animals↗