[Biological functions and therapeutic properties of angiogenins].

The review is devoted to an analysis of recently published data on the biological functions of angiogenins with a view to their potential use as an active basis for new pharmaceuticals and cosmetics.

Distribution and elimination of milk angiogenin in mouse immunocompetent organs and brain.

Dynamics of angiogenin content in the serum, thymus, bone marrow, and brain of mice was studied after intravenous injection. The maximum angiogenin retention was detected in the thymus, while high rate of its elimination in the brain.

Cow milk angiogenin induces cytokine production in human blood leukocytes.

Angiogenin isolated from cow milk induces the production of cytokines IL-1beta, IL-6, and TNF-alpha in human leukocytes; the level of production of each cytokine depends on the concentration of the preparation, and the dynamics of production depends on the time from the beginning of induction. Simultaneous treatment with angiogenin and phytohemagglutinin had an additive effect on the production of cytokines, the time of this effect manifestation being individual for each cytokine.

Stabilizing effect of milk angiogenin on the crystal structure of biological fluids.

We revealed a new property of angiogenin to restore the crystal structure of biological fluids (human blood plasma and exudates) impaired in various pathologies.

[Milk angiogenin (Review)]. / Angiogenin moloka (Obzor).

Recent data on angiogenin, a multifunctional member of pancreatic RNase protein superfamily, are summarized. Advances in the investigation of angiogenin structure, function, and properties are analyzed. Potentialities in natural angiogenin production from inexpensive dairy by-products are demonstrated.

[Milk ultrafiltrate as a promising source of angiogenin]. / Molochnyi ul'trafil'trat--perspektivnyi istochnik angiogenina.

The use of membrane technologies in the production of soft cheese (children's food) is associated with the appearance of up to 80% of angiogenin in the ultrafiltrate. An electrophoretically homogeneous preparation of angiogenin (MW approximately 17 kDa) was obtained from milk ultrafiltrate by two-stage ion-exchange chromatography. The yield of the angiogenin was approximately 60%, which corresponds to a 586-fold purification of the raw material. The obtained preparation retained stability in the course of lyophilization and could be stored at 4 degrees C for a long time without decomposition.

[Penetration of cow milk angiogenin into the blood after peroral administration in mice]. / Proniknovenie v krov' myshei vvodimogo peroral'no angiogenina iz korov'ego moloka.

The cow milk angiogenin consumed by mice perorally penetrated from the gastrointestinal tract in the blood flow. In the experimental animals, the blood level of exogenous angiogenin first increased to reach a maximum, and then gradually decreased to zero. The dynamics of this process depends on the age of animals. The data obtained suggest that the cycle of perorally introduced cow milk angiogenin in blood is realized in the infantile-juvenile mice at a higher rate than in the adult-presenile mice.

[Angiogenin content in human milk in the early period of lactation]. / Soderzhanie angiogenina v zhenskom moloke v rannii period laktatsii.

The content of angiogenin in human milk and dairy produce for feeding of children of the first year of life is investigated. It is revealed, that the highest concentration of angiogenin in human milk takes place in colostric period (18.00 +/- 0.72 mg/l). During the subsequent time of lactation the concentration of angiogenin keeps at a level 2.00 +/- 0.06 mg/l. In products of infant's feeding the angiogenin either was absent, or its concentration was much lower, than in breast milk.

[Immunoenzyme analysis of angiogenin in cow's milk]. / Immunofermentnyi analiz angiogenina v moloke korov.

Competitive enzyme immunoassay based on polyclonal antibodies can be used for determining the content of angiogenin in milk. These polyclonal antibodies had no cross-reactions with ribonuclease or other milk whey proteins. Milk angiogenin levels in samples taken fvom animals of a separate population varied from 2.09 to 4.85 mg/l. Unlike cow milk productivity, the number of calvings affects the milk angiogenin content.

[Purification of angiogenin from cow's milk]. / Ochistka angiogenina iz korov'evo moloka.

A new method for the purification of bovine angiogenin is proposed which is based on the use of CM-cellulose, CM-Toyopearl, and Butyl-Toyopearl. Electrophoretically homogeneous protein was obtained with a 49% yield and 12,000-fold purification.

[Determination of angiogenin in cow's milk based on a competitive test "pancreatic RNAase/placental inhibitor of RNAase--angiogenin"]. / Opredelenie angiogenina v korov'em moloke na osnove konkurentnoi proby "pankreaticheskaia RNKaza/platsentarnyi ingibitor RNKazy-- angiogenin".

Contents of active factor of blood vessel growth angiogenin was analyzed in cow's milk by the method of competitive test in system "pancreatic RNAase/placental inhibitor of RNAase-angiogenin". High level of RNAase in milk limits using this test. To avoid this limitation the method of RNAase elimination from milk was elaborated.

[Quantitative determination of cattle angiogenin]. / Kolichestvennoe opredelenie angiogenina byka.

Polyclonal antibodies to a milk antigen were obtained by a standard immunization procedure. The possibility was demonstrated to use the peroxidase-antibody conjugate in a competitive immunoenzymatic test. The minimal amount of the antigen determined by this method is 10 ng/ml.

[The effect of angiogenin on blood vessel proliferation in rats]. / Vliianie angiogenina na proliferatsiiu krovenosnykh sosudov u krys.

Human gene-engineering angiogenin, administered in methylcellulose tablets into the rat cornea induces growth of the limbus blood vessels in nanogram doses. Speed of the growth of the newly forming capillaries increases with the angiogenin dose. Pancreatic ribonuclease, highly homologous in structure with angiogenin does not induce neovascularization under the same conditions. Activation of the blood vessels proliferation under the effect of angiogenin was also observed in rat skin, but at higher doses. Angiogenin injected in 3% agarose with low melting point into abdominal skin or into the ear skin induced neovascularization in doses no less than 3 mg. Conditions, envisaging depression of the tissue immune reactions to the heterogeneous protein did not eliminate the angiogenin effect. This allows to conclude that they are caused by the direct manifestation of the angiogenic qualities of the studies growth factor.

[The quantitative assessment of the biological activity of angiogenin]. / Kolichestvennaia otsenka biologicheskoi aktivnosti angiogenina.

Methods have been developed for the in vivo quantitative estimation of biological activity of angiogenin, a protein growth factor of blood vessels. The quantitative analysis of angiogenin with the methods of angiogenetic disks in isotopic modification requires nanogram amounts of the angiogenetic. The cutireaction test is less sensitive though technically simple. The methods are developed on animal (mouse and rat) tissues.

Expression of the hAng gene in Escherichia coli; isolation and characterization of human recombinant Ser-(-1) angiogenin.

Recombinant human angiogenin has been synthesized in Escherichia coli with the aid of a human angiogenin gene (hAng) cloned by Neznanov et al (1990) from a human complementary DNA (cDNA) library. The gene has been expressed by use of a new type of expression vector called a 'TGATG vector' (plasmid pPR-TGATG-1; Mashko et al 1990a). The highest level of accumulation of the recombinant angiogenin (6%-8% of the total cell protein) was observed in E. coli strain BL21 carrying a temperature-amplifiable version of the plasmid. The synthesized polypeptide carries an additional serine residue at its N terminus in comparison with natural angiogenin. Furthermore, the initiator methionine residue of the recombinant protein is removed with high efficiency by E. coli terminal aminopeptidase. Simple procedures for purification of the recombinant angiogenin from the insoluble fraction of cell protein, and for refolding the protein allowed the isolation of almost 5 mg recombinant angiogenin g-1 wet bacterial biomass. The recombinant Ser-(-1) angiogenin displayed the same biological properties (specific RNAase activity and the ability to induce blood vessel growth on the sclera of experimental animals) as its natural counterpart isolated from human blood.

[The effect of alkylresorcinol on the respiration and synthesis of nucleic acids and proteins in isolated thymocytes]. / Vliianie alkilrezortsina na dykhanie, sintez nukleinovykh kislot i belka v izolirovannykh timotsitakh.

The effect of the membranotropic agent alkylresorcinol 5C10 on the respiration, nucleic acid and protein synthesis in isolated thymocytes was studied. Within the 5C10 concentration range of 10(-7)-10(-5) M, the inhibition of respiration and incorporation of labelled precursors into thymocyte proteins and DNA was observed. In case of respiration and protein synthesis, a 50% inhibition was observed at alkylresorcinol concentrations of 10(-8) and 0.5.10(-5) M, respectively. The rate of 3H-thymidine incorporation into DNA progressively decreased already at 5C10 concentration of 10(-7) M. At 10(-6) M alkylresorcinol its inhibiting effect on DNA synthesis was about 30% and it did not change with a further rise in the inhibitor concentration up to 10(-5) M. In contrast, the rate of RNA synthesis significantly increased (ca. by 20%) within the alkylresorcinol concentration range of 10(-6)-10(-5) M. At 5C10 concentrations above 10(-5) M, the state of thymocytes in the preagglutination period appeared to be critical and was characterized by a dramatic inhibition of all the parameters under study. The experimental results suggest that alkylresorcinol 5C10 causes the inhibition of processes that are functionally coupled with biological membranes.

[Inhibition of synthesis of nucleic acids, proteins and respiration in isolated thymocytes by anthracyclines]. / Ingibirovanie antratsiklinami sinteza nukleinovykh kislot, belka i dykhaniia v izolirovannykh timotsitakh.

The effect of anthracycline antibiotics such as carminomycin, daunomycin (rubomycin) and adriamycin on respiration and synthesis of nucleic acids and protein was studied comparatively. The anthracyclines inhibited the processes. By their efficacy in that respect they could be arranged in the following order: carminomycin greater than rubomycin greater than adriamycin. Thus, 50 per cent inhibition of nucleic acid synthesis in the thymocytes required 0.027, 0.044 and 0,173 mM of carminomycin, rubomycin and adriamycin respectively. Protein synthesis and respiration in the thymocytes were less sensitive to the effect of the anthracyclines than synthesis of nucleic acids. The study results were compared with the literature data on the effect of the compounds on respiration and synthesis of nucleic acids and protein in tumour and bacterial cells.

[Effect of weightlessness on the DNA replicative function of rat hepatocytes]. / Vliianie nevesomosti na replikativnuiu funktsiiu DNK gepatotsitov krys.

The replicative function of DNA of liver cells of rats exposed to strong stress-effects, e.g. suspension for 2.5 hours a day for 6 days, decreased. The rat studies onboard biosatellites of the Cosmos series have demonstrated that a prolonged exposure to microgravity (up to 22 days) is not a stressogenic factor for the DNA synthetic system of liver cells. The transition from 1 g to microgravity cannot be viewed as a strong stressor either, because the rate of DNA synthesis in liver cells at an early period of adaptation to microgravity remains within the normal limits. However, this parameter decreases significantly during the recovery period following 18-22-day flights. Therefore changes in cellular processes related to the DNA replicating function in hepatocytes should be expected to occur in the postflight period rather than at an early period of adaptation to microgravity.