silicon and silatrane

Topics: Adjuvants, Immunologic; Adolescent; Adult; Alopecia; Animals; Antineoplastic Agents; Blood Coagulation; Bridged Bicyclo Compounds, Heterocyclic; Child; Endocrine Glands; Female; Hair; Humans; Insecta; Lethal Dose 50; Liver; Liver Regeneration; Organosilicon Compounds; Plants; Reproduction; Silicon; Wound Healing

On repeated thawing at room temperature of frozen preparations of heavy microsomes from rat livers, HMGCoA reductase activity was solubilized due to limited proteolysis. This soluble enzyme was partially purified by fractionation with ammonium sulfate and filtration on Sephacryl S-200 column. The active enzyme was coeluted with a major 92 kDa-protein and was identified as a 58 kDa-protein after separation by SDS-PAGE and immunoblotting. Ethoxysilatrane, a hypocholesterolemic compound, which decreased the liver-microsomal activity of HMGCoA reductase on intra-peritonial treatment of animals, showed little effect on the enzyme activity with isolated microsomes or the 50 kDa-soluble enzyme when added in the assay. But it was able to inhibit the activity of the soluble 58 kDa-enzyme in a concentration-dependent, reversible manner. Cholesterol and an oxycholesterol were without effect whereas chlorophenoxyisobutyrate and ubiquinone showed small inhibition under these conditions. The extra region that links the active site domain (50 kDa protein) to the membrane, present in the 58 kDa-protein appears to be involved in mediating the inhibition by silatrane.

Topics: Animals; Anticholesteremic Agents; Blotting, Western; Bridged Bicyclo Compounds; Bridged Bicyclo Compounds, Heterocyclic; Chromatography, Gel; Hydroxymethylglutaryl CoA Reductases; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Male; Microsomes, Liver; Organosilicon Compounds; Rats; Rats, Inbred Strains; Silicon; Solubility

A stimulating effect of methylethyl(silatrane-I-ilmethyl)-sulphonium iodides, 1-(ethoxy)silatranes and 1-(chloromethyl)silatrane on the processes of rat test acetate ulcer healing is studied. Silatranes efficiency is not inferior to oxyferriscorbone and exceeds that of methacil. It is shown that all preparations inhibit the processes of lipids peroxidation in the blood, in liposomes and stomach tissue.

Topics: 2,3-Diketogulonic Acid; Alloxan; Animals; Anti-Ulcer Agents; Bridged Bicyclo Compounds; Bridged Bicyclo Compounds, Heterocyclic; Drug Combinations; Ferric Compounds; Lipid Peroxidation; Organosilicon Compounds; Rats; Silicon; Stomach Ulcer; Uracil

On changing the phosphorus coordination from four to five via a trigonal bipyramidal geometry in phospholipid model systems, a conformational change is initiated around the C2-C3 linkage caused by enhanced electrostatic repulsion between the atoms O3 and O2, situated in the axis of the trigonal bipyramid. This is supported by the absence of conformational change upon substitution of O2 by methylene. With solid-state cross-polarization and magic-angle spinning 13C-NMR it is shown that such a conformational transmission leads to an increased packing density of the lipid chains. It seems to us that changes in lipid packing caused by conformational transmission may also occur when pentacoordination is present transiently, as under biological conditions, thereby inducing an activation of the transport proteins that are embedded in the membrane.

Topics: Bridged Bicyclo Compounds; Bridged Bicyclo Compounds, Heterocyclic; Chemical Phenomena; Chemistry; Energy Transfer; Lipids; Magnetic Resonance Spectroscopy; Membrane Fluidity; Molecular Conformation; Organosilicon Compounds; Oxygen; Phosphates; Phospholipids; Silicon

It was the aim of our investigations to increase the antitumor activity of cyclophosphamide. Therefore we applied a combined treatment with silatranes and isoniazid in relation 1:20:1. The effects were directed against a transplantable sarcoma 180. The parablastomatous invasive zone and the regional lymph nodes draining an implanted tumor were taken for the histochemical and morphological studies. The doses ranged from 50 to 175 mg of body mass. The combined derivatives inhibited tumor growth by 70% in relation to the control. The authors connect the limitation of tumor progression in the applied experimental model in mice with the active response of T dependent zone of the regional lymph nodes, the rebuilding of stroma within the borderline invasive zone and the changes within the composition of cellular immune response of the peritumor tissue.

Topics: Animals; Bridged Bicyclo Compounds; Bridged Bicyclo Compounds, Heterocyclic; Bridged-Ring Compounds; Cyclophosphamide; Drug Combinations; Female; Isoniazid; Lymph Nodes; Male; Mice; Mice, Inbred BALB C; Neoplasm Invasiveness; Organosilicon Compounds; Sarcoma 180; Silicon

Topics: Animals; Aorta, Thoracic; Aortic Diseases; Arteriosclerosis; Bridged Bicyclo Compounds; Bridged Bicyclo Compounds, Heterocyclic; Bridged-Ring Compounds; Cholesterol, Dietary; Drug Evaluation, Preclinical; Lipid Metabolism; Organosilicon Compounds; Rabbits; Silicon; Time Factors

Experiments on rats were made to study the effect of I-(chloromethyl) silatrane and I- (ethoxy) silatrane and that of triethanolamine and chloromethyl triethoxysilane on biochemical parameters of granular-fibrous tissue. The preparations were applied to a wound defect in the form of liniments. Silatranes were found to stimulate proliferation of the cells and to increase their biosynthetic activity, to favour accumulation of collagen and non-collagenic proteins, and reduction of the inflammatory phenomena. The silicon-containing fragment of the silatrane molecule chloromethyl triethoxysilane produced an analogous but less marked action. Triethanolamine containing no silicon was found to be as less active. These data indicate that silicon entering the silatrane grouping is of great importance for the occurrence of its biological activity.

Topics: Animals; Bridged Bicyclo Compounds; Bridged Bicyclo Compounds, Heterocyclic; Bridged-Ring Compounds; Ethanolamines; Granulation Tissue; Liniments; Organosilicon Compounds; Rats; Silicon; Stimulation, Chemical

Experiments on rats were performed to study the effect of I-/chlormethyl/silatrane and I-/ethoxy/silatrane as well as that of triethanolamine and /chlormethyl/triethoxysilane on the biochemical characteristics of granular-fibrous tissue. The drugs were applied to the wound in the form of liniments. Silatranes stimulated cell proliferation and raised biosynthetic activity of the cells. They also favoured collagen and non-collagenous protein accumulation and reduced the inflammatory manifestations. The silicon-containing fragment of the silatrane molecule, /chlormethyl/triethoxysilane, produced an analogous but less pronounced action. Triethanolamine containing no silicon appeared to be far less active. These data indicate that the presence of silicon in the silatrane grouping is of great importance for its effective biological function.

Topics: Animals; Bridged Bicyclo Compounds; Bridged Bicyclo Compounds, Heterocyclic; Bridged-Ring Compounds; Granulation Tissue; Liniments; Organosilicon Compounds; Rats; Silicon; Wound Healing; Wounds and Injuries

Topics: Animals; Bridged Bicyclo Compounds; Bridged Bicyclo Compounds, Heterocyclic; Bridged-Ring Compounds; Guinea Pigs; Hair; Hair Removal; Ointments; Organosilicon Compounds; Silicon; Skin

Effect of some organosilicon compounds from the class of silatranes on the biosynthesis of collagen in cartilagenous tissue of chick embryos in vitro was studied. The criteria for assessing the intensity of collagen biosynthesis was the formation of peptide bond 14C-hydroxyproline from 14C-proline of incubation medium. All the compounds studied (methylsilatrane, ethoxysilatrane and chloromethylsilatrane) stimulated total protein biosynthesis and collagen biosynthesis in cartilagenous tissue of chick embryos. The most pronounced stimulation of the biosynthesis of collagen was observed at 3-10(-3) M concentration of silatranes within 180 min. of incubation (14C-proline was added to the incubation medium 60 min after the beginning of the incubation). The activity of partly purified collagen prolyl-hydroxylase in the presence of silatranes was also studied.

Topics: Animals; Bridged Bicyclo Compounds, Heterocyclic; Cartilage; Chick Embryo; Collagen; Dose-Response Relationship, Drug; Hydroxyproline; Organosilicon Compounds; Procollagen-Proline Dioxygenase; Proline; Silicon; Structure-Activity Relationship