title: Proline rich polypeptide (PRP-1) increases the superoxide-producing and ferrihemoglobin reducing activities of cytochrome B(558) isoforms from human lymphosarcoma tissue cells.
abstract: The two cytochromes (cyt) b(558) of acidic nature, one-95-100 kDa and another one, 60-70 kDa were isolated for the first time from the human's lymphosarcoma tissue cells using gel filtration and ion exchange chromatography. These hemoproteins possess NADPH dependent O(2)(-)-producing and ferrihemoglobin-reducing activities. The incubation of neuropeptide PRP-1 (5 μg) with cytochrome b(558), caused elevation of these activities. The gel filtration results indicated possible binding of PRP-1 to these cytochromes b(558). PRP-1 activated both NADPH dependent O(2)(-)-producing and ferriHb-reducing activities of the cyt b(1)(558) and cyt b(2)(558), obtained from human lymphosarcoma tissue cells. One can assume that PRP-1 associated with cyt b(558) on the surface of the tumor cells by increasing both NADPH dependent O(2)(-)-producing and ferriHb-reducing activities of cyt b(558), increases the oxidation- reduction status. Changing the oxidation-reduction status and oxygen homeostasis of the tumor cells by PRP-1 can serve as one of the possible explanation of antitumorigenic effect of this cytokine.
authors.affiliation: H. Buniatyan Institute of Biochemistry, National Academy of Sciences, 5/1 Paruir Sevak Str., Yerevan 0014, Republic of Armenia. rafael-nelly@mail.ru
authors.forename: G M
authors.initials: GM
authors.lastname: Simonyan
authors.forename: K A
authors.initials: KA
authors.lastname: Galoian
authors.forename: R M
authors.initials: RM
authors.lastname: Simonyan
authors.forename: M A
authors.initials: MA
authors.lastname: Simonyan
authors.forename: A A
authors.initials: AA
authors.lastname: Galoyan
mesh_terms: D023181:Antimicrobial Cationic Peptides; D003573:Cytochrome b Group / Q000378:metabolism*; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism*; D008706:Methemoglobin / Q000378:metabolism*; D019255:NADPH Oxidases / Q000378:metabolism*; D010455:Peptides / Q000494:pharmacology*; D013057:Spectrum Analysis / Q000379:methods; D013481:Superoxides / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: D023181:Antimicrobial Cationic Peptides; D003573:Cytochrome b Group; D007527:Isoenzymes; C540268:PRP-1 peptide; D010455:Peptides; D013481:Superoxides; D008706:Methemoglobin; C036888:cytochrome b558; D019255:NADPH Oxidases