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Pegylated hyaluronate-endo-β-N-acetylhexosaminidase considerably potentiates the hemostimulating effects of erythropoietin due to intensification of proliferation and differentiation of erythroid precursors against the background of enhanced secretion of hemopoietins by nonadherent hemopoiesis-inducing environment cells and elevation of serum erythropoietin concentration. The use of the enzyme allows 10-fold reduction of the maximum effective erythropoietin dose.

Hypoglycemic effect of hyaluronate-endo-β-N-acetylhexosaminidase immobilized by electron-beam synthesis nanotechnology (imHEA-HA) was studied in experimental insulin-dependent and insulin-independent diabetes mellitus. The drug exhibited a hypoglycemic effect of its own and potentiated the pharmacological effect of exogenous insulin injected in vivo. Studies on liver cell culture demonstrated an increase of cell sensitivity to insulin after treatment with imHEA-HA.

We studied the secretory function of the liver and bone marrow microenvironment cells under conditions of chronic CCl4-induced hepatitis. Enhanced production of substances stimulating parenchymal tissue-specific precursors and stem cell homing factors by liver cells was observed. In situ binding of stem cells by bone marrow elements increased due to production of various cooperation and adhesion factors against the background of reduced SDF-1 secretion.

We studied the effect of mobilization of bone marrow multipotent stem cells induced by intragastric administration of pegylated hyaluronate-endo-β-N-acetylhexosaminidase (Peg-HEAHA) on hemopoiesis under conditions of experimental chronic hepatitis. Peg-HEAHA increased the counts of hemopoietic precursors in the hemopoietic tissue against the background of their decelerated maturation. This was paralleled by a short-term decrease in the count of neutrophilic granulocyte in the bone marrow and a slight increase of neutrophil count in the peripheral blood.

Pharmacological characteristics of somatotropin pegylated using electron-beam synthesis nanotechnology (PEG-STH) were studied. Oral PEG-STH stimulated the intensity of protein and lipid metabolism and endochondral bone growth without modifying the processes of periosteal and endosteal bone formation. Specific activity of this substance administered orally significantly surpassed that of parenteral non-modified growth hormone.

The influence of oral inulin administration on glucose and fructose content in blood, glucose and ketone bodies in urine, and fructose-2,6-diphosphate content in liver was investigated in rats with streptozotocin diabetes. Short-term administration (during 5-6 days) of 0.5% inulin solution caused three-fold increase of blood fructose compared with control, normalisation of blood glucose and disappearance of glucose- and ketoneuria. The level of fructose-2,6-di-phosphate in liver increased to the control level. Inulin administration during 12 days caused five-fold increase of blood fructose compares with control, glucose level increased up to the level of uncurred diabetes (22 mmol/1), glucose- and ketoneuria appeared. The content of fructose-2,6-diphosphate in the liver decreased to diabetic level.

The activity of phosphofructokinase-2, fructose, 1,6-bisphosphatase, glucokinase, and also the level of fructose 2,6-bisphosphate and glycogen were examined in the liver of normal, and streptozotocin-diabetic rats. It was shown that the activity of phosphofructokinase-2 was decreased in the liver of diabetic rats. Besides that the activity determined at pH 6.6 (the "active" or unphosphorylated enzyme form) was 3-fold reduced whereas the "total" enzyme activity as measured at pH 8.5 was lowered 1,7-fold. The phosphofructokinase-2 activity assay at two pH values allows to estimate a degree of phosphorylation of bifunctional enzyme which is markedly enhanced in diabetes. The fall of the bifunctional enzyme k in case activity is accompanied by the lowered fructose 2.6-bisphosphate level, increased fructose 1,6-bisphosphatase activity that in turn favours the liver tissue glycolysis inhibition and gluconeogenesis enhanced in diabetes.

The molecular mechanisms of the inhibitory action of fructose- 2,6-bisphosphate (F-2,6-P2) on fructose-1,6-biphosphatase (FB-Pase-1), the key enzyme of gluconeogenesis, and the those of the activating action of F-2,6-P2 on phosphofructo-1-kinase (PFK-1), the key enzyme of glycolysis, NMR spectroscopy first provided direct evidence for the fact that F-2,6-P2 was involved in the regulation of the sedoheptulose cycle of a nonoxidative stage of the pentosephosphate pathway. Procedures were developed in measuring the levels of F-2,6-P2 in the cell of experimental animal tissues and human blood lymphocytes. Naturally different emergencies substantially affected the F-2,6-P2 system by triggering these or those mechanisms controlling the activity of enzymes of this system. Vanadium-containing compounds were demonstrated to have a positive action on carbohydrate metabolism in diabetic (streptozotocin-induced) rat hepatocytes.

Content of fructose-2,6-bisphosphate was drastically decreased (about 5-fold) in hepatocyte suspension obtained from rats with streptozotocin-induced diabetes, as compared with that of control animals. At the same time, activity of fructose-1,6-bisphosphatase was increased 2-fold in these hepatocytes. Incubation mixture of the hepatocytes from the diabetes impaired animals contained only low amounts of lactate.

The authors discuss methods for purification of pyrophosphate fructose-6-phosphate phosphotransferase from potato tuber and enzymatic method for measuring fructose-2,6-biphosphate concentration in isolated hepatocytes of normal and diabetic rats and come to a conclusion on a higher sensitivity of the method they propose in comparison with the method making use of commercial phosphofructokinase from rabbit muscles. Their method may be used for fructose-2,6-biphosphate measurements in various biologic materials.

Captopril is the first oral inhibitor of angiotensin-converting enzyme, which has a strong effect on patients with hypertonic states. The influence of the preparation was studied on liver drug-metabolizing enzymic systems of rats in two ways of oral administration-single and a 10-day treatment with a dose of 75 mg/kg. The effect on the levels of microsomal cytochrome B5 and P450 as well as on that of hem was investigated. The activities of some enzymes from the first and second phases of biotransformation were determined. There no changes in the examined parameters 1 h after single oral treatment with 75 mg/kg of captopril. Induction of some of the examined enzymes was observed after a 10-day treatment with 75 mg/kg r. o. of captopril once daily: there was statistically significant elevation of the level of cytochrome P450 as well as of the activity of ethylmorphindelethylase and HA-DPH-cytochrome-C-reductase. The results show that there is probably induction at the first phase of phenobarbital type of drug metabolism.

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.

We studied the effect of hyaluronate-endo-β-N-acetylhexosaminidase on the secretory function of the liver and bone marrow microenvironment cells in chronic hepatitis. Enhanced production of substances stimulating parenchymal tissue-specifi c 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.

Pegylated hyaluronate-endo-β-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.

The hemopoiesis-stimulating effect of combined treatment with immobilized oligonucleotides and hyaluronidase preparations was studied during cytostatic-induced myelosuppression caused by cyclophosphamide administration. Immobilized hyaluronidase was shown to increase the effi ciency of correction of changes in the erythroid and granulocytic hemopoietic stems with immobilized oligonucleotides. This potentiation of the effect of immobilized oligonucleotides by immobilized hyaluronidase was related to an increase in functional activity of committed hemopoietic precursors.

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.

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.

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.

High hepatoprotective activity of granulocytic CSF and hyaluronidase immobilized using electron-beam immobilization technology was demonstrated on the model of CCl(4)-induced hepatitis: the preparations produced anticholestatic, anti-inflammatory, and antisclerotic effects. These effects developed against the background of stimulation of bone marrow multipotent precursor cells and their mobilization into circulation accompanied by an increase in the content of parenchymatous progenitor cells in the liver. The most pronounced positive effect was observed in combined treatment with the test preparations.