title: Protective effect of carboxyethylgermanium sesquioxide (Ge-132) on superoxide generation by 60Co-irradiated leukocytes.
abstract: The carboxyethylgermanium sesquioxide, Ge-132, is an organogermanium compound which has been shown to modulate leukocyte functions. In this study, we examined the effect of Ge-132 on the generation of superoxide radicals (O2-) either from leukocytes or in cell-free system, employing the highly sensitive 2-methyl-6-[p-methoxy-phenyl]-3,7-dihydroimidazo[1,2-alpha]pyra zin-3-one (MCLA)-dependent chemiluminescence method and the specific electron spin resonance/spin trapping method, respectively. In addition, the in vitro protective effect of Ge-132 on the leukocytes irradiated with 60Co was studied. The incubation with Ge-132 resulted in an increase in basal O2- release of intact leukocytes, but had no effect on O2- generation from leukocytes stimulated with phorbol myristate acetate (PMA). Irradiation with 60Co decreased the O2- generation from leukocytes in a dose-dependent manner. Ge-132 had no effect on basal O2- release from 60Co-irradiated leukocytes, but it prevented the decrease in PMA-stimulated O2- generation by irradiated leukocytes. Ge-132 itself had no superoxide scavenging activity in cell-free system. On the other hand, higher concentrations of Ge-132 had decreasing effects on both basal O2- release and PMA-stimulated O2- generation from leukocytes, but they did not affect leukocyte viability. Above results indicate that 1) Ge-132 can stimulate the basal O2- release from leukocytes, 2) Ge-132 can prevent the decrease of O2- generation by 60Co-irradiated leukocytes, 3) in higher concentrations, Ge-132 may have a membrane stabilizing effect.
authors.affiliation: Second Department of Internal Medicine, Semmelweis University Medical School, Budapest, Hungary.
authors.forename: L
authors.initials: L
authors.lastname: Prónai
authors.forename: S
authors.initials: S
authors.lastname: Arimori
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D003037:Cobalt Radioisotopes; D005720:Gamma Rays; D005857:Germanium; D006801:Humans; D066298:In Vitro Techniques; D007962:Leukocytes / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D008297:Male; D009942:Organometallic Compounds / Q000494:pharmacology*; D010101:Oxygen Consumption / Q000187:drug effects; D011422:Propionates; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D003037:Cobalt Radioisotopes; D009942:Organometallic Compounds; D011422:Propionates; D005857:Germanium; D013481:Superoxides; C066750:propagermanium; D013755:Tetradecanoylphorbol Acetate