Ca<Superscript>2+</Superscript>, Mg<Superscript>2+</Superscript>-dependent DNase Involvement in Apoptotic Effects in Spermatozoa of Sea Urchin <Emphasis Type="Italic">Strongylocentrotus intermedius</Emphasis> Induced by Two-Headed Sphingolipid Rhizochalin

Previously, we have purified three distinct DNases from spermatozoa of sea urchin Strongylocentrotus intermedius and we suppose the role of Ca²⁺, Mg²⁺-dependent DNase (Ca, Mg-DNase) in apoptosis of spermatozoa. Two-headed sphingolipid rhizochalin (Rhz) induced characteristic apoptotic nuclear chromatin changes, internucleosomal DNA cleavage, and activation of caspase-9, caspase-8, and caspase-3 in spermatozoa as was shown by fluorescence Hoechst 33342/PI/FDA analysis, DNA fragmentation assay, and fluorescence caspase inhibitors FAM-LEHD-fmk, FAM-IETD-fmk, and FAM-DEVD-fmk, respectively. Inhibitor of caspase-3 z-DEVD-fmk subdued Rhz-induced internucleosomal ladder formation, which confirmed the major role of caspase-3 in apoptotic DNA cleavage probably through Ca, Mg-DNase activation. Participation of sea urchin Ca, Mg-DNase in apoptosis of spermatozoa was demonstrated by ions Zn²⁺ blocking of Rhz-induced DNA fragmentation due to direct inhibition of the Ca, Mg-DNase and internucleosomal cleavage of HeLa S and Vero E6 cell nuclei chromatin by highly purified Ca, Mg-DNase.     

Synthesis and Analysis of Properties of an Immunogenic Fragment from NS4A Polypeptide of Hepatitis C Virus

Russian Journal of Bioorganic Chemistry - The work is aimed at the synthesis and analysis from NS4A of hepatitis C virus (HCV) antigen peptide fragment that contains a conserved B-cell and T-helper...     

The anticancer activity of 3- and 10-bromofascaplysins is mediated by caspase-8, -9, -3-dependent apoptosis

3- and 10-Bromofascaplysins was previously found to possess cytotoxic activity. In this study, we investigated their cancer preventive and proapoptotic properties. These effects were tested on mouse skin epidermal JB6 P⁺ Cl41 cell line, its stable transfectants, and human tumor HL-60, THP-1, SNU-C4, SK-MEL-28, DLD-1, MDA-MB-231, and HeLa cells using a variety of assessments, including a cell viability (MTS) assay, flow cytometry, anchorage-independent soft agar assay, luciferase assay, mitochondrial permeability assay, and Western blotting. 3- and 10-Bromofascaplysins were effective at submicromolar concentrations as the anticancer agents, which exerted their action, at least in part, through the induction of caspase-8, -9, -3-dependent apoptosis.     

Study of asymmetrically substituted myo-inositols. XXXIX. The synthesis of conjugate of 2',3'-didehydro-3'-dehydroxythymidine with phosphatidylinositol: a new nucleoside phospholipid with potential anti-HIV activity

A partially protected phosphatidylinositol with a free hydroxyl group in the cyclitol moiety was synthesized by phosphorylation of a tetrasubstituted myo-inositol using the H-phosphonate and phosphoamidite methods. The H-phosphonate method was advantageous for the synthesis of selectively protected monophosphoinositide due to a lesser number of stages. Two schemes for the conjugation of 2',3'-didehydro-3'-dehydroxythymidine with phosphatidylinositol using succinic acid as a linker were tested in the synthesis of the target nucleoside phospholipid.     

Effect of Lipid Components on Immunogenicity of Synthetic Fragment of Hepatitis C Virus NS4A Antigen

Russian Journal of Bioorganic Chemistry - The aim of this study was to investigate the effect of lipid components on the immunogenicity of a synthetic 24-mer peptide containing B- and Th-epitopes....     

Design of the New Molecular Transport Systems for the Nucleosides-Pharmacophores Carrying.

Abstract

The structure design of a specific and nonspecific transport systems for nucleosides was proposed. A number of model compounds were synthesized.

# AZT-2,3′-dideoxy-3′-azidothymidine. d4T-3′-deoxy-2′,3′-didehydrothymidine, ddC -2,3′-dideoxcytidine. ddI -2′.3′-dideoxyinosine. DMAP-4-N,N-dimetylaminopyridyne, DCC-dicyclohexylcarbodiimide.     

Differential effects of triterpene glycosides, frondoside A and cucumarioside A2-2 isolated from sea cucumbers on caspase activation and apoptosis of human leukemia cells

Frondoside A is a pentaoside having an acetyl moiety at the aglycon ring and xylose as a third monosaccharide residue. Cucumarioside A₂-2 is a pentaoside having glucose as a third monosaccahride unit. We compared the effects of frondoside A and A₂-2 for cell death-inducing capability with close attention paid to structure-activity relationships. Both frondoside A and A₂-2 strongly induced apoptosis of leukemic cells. Frondoside A-induced apoptosis was more potent and rapid than A₂-2-induced apoptosis. A₂-2-induced but not frondoside A-induced apoptosis was caspase-dependent. This suggests that holothurians may induce apoptosis of leukemic cells caspase-dependently or -independently, depending on the holothurian structure.