Antifibrotic activity of conjugates based on amphiphilic pluronic F68 and hydrophobic pluronic L31 with hyaluronate-endo-ß-N-acetylhexosaminidase in pulmonary fibrosis.

Antifibrotic activity of intranasally administered conjugates of pluronics L31 and F68 with hyaluronate-endo-ß-N-acetylhexosaminidase was studied in C57Bl/6 mice under conditions of single and repeated bleomycin-induced injury to the alveolar epithelium. Conjugates were prepared using the technique of protein immobilization with ionizing radiation. We demonstrate that in cases of single and repeated injuries to the alveolar epithelium, the conjugates administered during phases of inflammation or deposition of fibrotic masses prevent the development of pulmonary fibrosis. The conjugates demonstrated more pronounced antifibrotic activity than hyaluronate-endo-ß-N-acetylhexosaminidase. The conjugate based on hydrophobic pluronic L31 showed higher effectiveness in comparison with the conjugate based on amphiphilic pluronic F68.

Specific effects of chondroitin sulfate-modified hyaluronidase on the function of progenitor cells.

We have demonstrated the possibility of stimulation of the function of various types of precursor cells with hyaluronidase modified with chondroitin sulfate. Parenteral administration of modified hyaluronidase increased the number of fibroblast, granulomonocyte, and erythroid CFU in the hemopoietic tissue. The changes in the pool of mesenchymal progenitor cells were more pronounced in comparison with those induced by native enzyme.

Effect of immobilized hyaluronidase on stem and progenitor cells in pulmonary fibrosis.

The effect of immobilized hyaluronidase on stem and progenitor cells of the lungs was studied on the model of partially reversible toxic bleomycin-induced pulmonary fibrosis in C57Bl/6 mice. During the inflammation phase, immobilized hyaluronidase reduced infiltration of alveolar interstitium with hemopoietic stem cells Sca-1(+), c-Kit(+), CD34(-), (CD3, CD45R (B220), Ly6C, Ly6G (Gr1), CD11b (Mac1), TER-119)(-). Improvement of histological parameters of bleomycin lungs during the phase of collagen fiber deposition after the treatment was accompanied by accumulation of mesenchymal multipotent stromal cells (CD31(-), CD34(-), CD45(-), CD44(+), CD73(+), CD90(+), CD106(+)decrease in the population of pan-hemopoietic cells (CD45(+)), accelerated restoration of the content of endothelial cells, and inhibition of clonal activity of fibroblast precursors (CD45(-)).

Effect of pegylated hyaluronate-endo-ß-N-acetylhexosaminidase on humoral mechanisms regulating the functions of progenitor cells during chronic hepatitis.

We studied the effect of hyaluronate-endo-ß-N-acetylhexosaminidase on the secretory function of the liver and bone marrow microenvironment cells in chronic hepatitis. Enhanced production of substances stimulating parenchymal tissue-specific precursors and stem cell homing factors by liver cells was revealed. At the same time, production of SDF-1 and other chemoattractants and adhesion factors of progenitor cells by bone marrow elements was reduced.

Antifibrotic effects of immobilized hyaluronidase in repeated bleomycin-induced lesions of the alveolar epithelium.

Antifibrotic activity of testicular hyaluronidase, immobilized on polyethylenoxide and obtained by electron beam synthesis, was studied on the model of bleomycin injuries to the alveolar epithelium (irreversible pneumofibrosis) in C57Bl/6 mice and compared to the effect of testicular hyaluronidase. Intranasal therapy with immobilized and testicular hyaluronidases prevented the deposition of fibrotic mass in the parenchyma of "bleomycin" lungs. The effect of immobilized hyaluronidase was more pronounced than that of testicular hyaluronidase. The studied compounds were virtually inessential for infiltration of the alveolar interstitium and alveolar tracts by lymphocytes, macrophages, neutrophils, and plasma cells. Unchanged histoarchitectonics of bleomycin-damaged lungs in immobilized hyaluronidase therapy was due to suppression of the progenitor fibroblast cells (CD45(-)).

Mechanisms underlying modulation of the pharmacological properties of pegylated erythropoietin by pegylated hyaluronate-endo-ß-N-acetylhexosaminidase.

Pegylated hyaluronate-endo-ß-N-acetylhexosaminidase was shown to potentiate significantly the hemostimulatory effect of pegylated erythropoietin. It was found that enhanced production of hemopoietin by adherent and non-adherent cells of the hemopoiesis-inducing microenvironment and elevated serum content of endogenous erythropoietin along with increased susceptibility of erythroid precursors to pegylated erythropoietin underlay this phenomenon.

Antifibrotic activity of hyaluronidase immobilized on polyethylenoxide under conditions of bleomycin-induced pneumofibrosis.

Hyaluronidase immobilized on polyethylenoxide obtained by electron bean synthesis was administered intranasally and intravenously to C57Bl/6 mice after intratracheal bleomycin and the enzyme effects on the development of pneumofibrosis in animals were studied. Intranasal immobilized hyaluronidase prevented connective tissue growth in the lungs exposed to bleomycin and virtually did not modulate the infiltration of the alveolar and alveolar duct interstitium by inflammatory cells (lymphocytes, macrophages, neutrophils, plasma cells). The antifibrotic effect developed sooner after intranasal inoculation of immobilized hyaluronidase and was more pronounced than after intranasal native hyaluronidase. Intravenous injection of immobilized hyaluronidase did not modify the inflammatory process and deposition of collagen fibrils in the lung parenchyma in pneumofibrosis.

Effects and mechanisms of hemopoiesis-stimulating activity of immobilized oligonucleotides under conditions of cytostatic myelosuppression.

Hemopoiesis-stimulating activity of immobilized oligonucleotide preparation was studied on the model of cytostatic myelosuppression induced by injection of cyclophosphamide and 5-fluorouracil. Immobilized oligonucleotides stimulated regeneration of erythro- and granulocytopoiesis in the bone marrow under conditions of cytostatic treatment. The counts of neutrophilic granulocytes and platelets in the peripheral blood increased. The stimulatory effect of the drug was more manifest in animals with active behavior. The mechanism of immobilized oligonucleotide effect was based on stimulation of functional activity of erythroid and granulocytic macrophage precursors.

Pharmacological properties of granulocytic colony-stimulating factor pegylated using electron beam synthesis nanotechnologies.

Granulocytic CSF pegylated using electron-beam synthesis nanotechnology exhibits pronounced granulomonocytopoiesis-stimulating and SC-mobilizing activity. More potent stimulation of committed precursors against the background of less pronounced activation of polypotent hemopoietic cells is a peculiarity of hemostimulating action of pegylated using electron-beam synthesis nanotechnology granulocytic CSF in comparison with its non-modified analog. The mobilizing effect of pegylated using electron-beam synthesis nanotechnology granulocytic CSF on early progenitor elements surpasses that of non-conjugated cytokine.

Mechanisms for hepatoprotective effects of hyaluronidase immobilized by the nanotechnology method of electron-beam synthesis.

Immobilized hyaluronidase (nanotechnology method of electron-beam synthesis) exhibited high hepatoprotective activity on the model of Cl4-induced hepatitis. This agent produced anticholestatic, anti-inflammatory, and antisclerotic effects. These effects were shown to accompany stimulation of multipotent bone marrow precursors, mobilization of these cells into the peripheral blood, and cell migration to the target organ increasing the number of parenchymal progenitor cells in the liver. The mechanisms for targeted migration of progenitor cells suggest a decrease in SDF-1 production by bone marrow stromal cells and increase in the synthesis of this factor by microenvironmental cells of the liver tissue.

Effect of hyaluronidase immobilized using electron-beam synthesis nanotechnology on sensitivity of progenitor cells to regulatory factors.

In vitro experiments demonstrated increased colony-forming capacity of erythroid, granulomonocytic, and mesenchymal progenitors of the bone marrow and parenchymal progenitor elements of the liver after treatment with immobilized hyaluronidase. Increased sensitivity of these progenitor cells to erythropoietin, granulocyte colony-stimulating factor, fibroblast growth factor, and stem cell factor, respectively, was demonstrated. Immobilized hyaluronidase enhanced the formation of tissue-specific hepatic CFU against the background of reduced yield of stromal precursors in liver tissue culture containing insulin.

Modulation of the blood-stimulating effect of immobilized granulocyte colony-stimulating factor by immobilized hyaluronidase.

We evaluated whether immobilized hyaluronidase can modify the hematotropic effect of immobilized granulocyte CSF (G-CSF). The preparation of immobilized hyaluronidase (50 arb. units per mouse) potentiated the specific effect of immobilized G-CSF on granulomonocytopoiesis. The preparation was shown to facilitate the indirect effect of immobilized G-CSF on hemopoiesis (stimulation of the erythroid and lymphoid hemopoietic stems). These changes were accompanied by an increase in functional activity of hemopoietic precursor cells, secretion of humoral factors by bone marrow myelokaryocytes, and concentration of hemopoietins in the serum.

Hemostimulating effects of erythropoietin immobilized by the nanotechnology method of electron-beam synthesis.

The hemostimulating effect of erythropoietin immobilized by the nanotechnology method of electron-beam synthesis was studied on the model of carboplatin-induced myelosuppression. Subcutaneous injection or oral administration of immobilized erythropoietin was followed by stimulation of erythropoiesis. The effect was most pronounced after parenteral treatment with this agent. The increase in proliferative activity and maturation of erythroid precursor cells serve as a factor determining acceleration of reparative processes in the hemopoietic tissue.

Role of stromal and Thy 1,2+ cells in the mechanisms of action of immobilized granulocyte colony-stimulating factor during cytostatic-induced myelosuppression.

The effects of immobilized granulocyte colony-stimulating factor (mediated by cells of the hemopoiesis-inducing microenvironment) on hemopoietic precursors of various classes were studied on the model of cytostatic-induced myelosuppression (administration of cyclophosphamide). The action of this preparation was compared with that of the standard preparation of granulocyte colony-stimulating factor. Thy 1,2(+)cells potentiated the effects of immobilized and standard granulocyte colony-stimulating factors on granulocyte-erythroid-macrophage-megakaryocyte precursors. Stromal cells were shown to potentiate the influence of these agents on granulocyte precursors. Induction of proliferation of precursor cells by the immobilized factor mediated by cells of the hemopoiesis-inducing microenvironment persisted for a longer period compared to that induced by the standard product.

Hemostimulating effects of immobilized hyaluronidase and their mechanisms during cytostatic-induced myelosuppression.

We studied the effect of immobilized hyaluronidase on hemopoiesis under conditions of cyclophosphamide-induced suppression. The preparation was shown to possess high hemostimulating activity. The stimulatory effect of hyaluronidase on the erithron was more pronounced than its effect on the granulocytic hemopoietic stem due to increase in functional activity of hemopoietic precursors and hemopoiesis-inducing microenvironment.