title: Phorbol ester at concentrations 10(-18)-10(-7) M inhibits lipid peroxidation in rat brain plasma membranes via activation of protein kinase C.
abstract: We studied the effects of 12-O-tetradecanoylphorbol-13-acetate (TPA) and protein kinase C (PKC) in a broad range of concentrations (10(-18)-10(-7) M) on lipid peroxidation (LP) in rat brain plasma membranes. TPA and PKC were shown to inhibit LP, the concentration curves had two maxima at 10(-15) M and 10(-12) M for TPA and at 10(-16) M and 10(-13) M for PKC. The combined action of TPA (10(-12) M) and PKC (10(-16) M) resulted in a synergic inhibition of LP. These data suggest PKC to have two (kinase and antioxidative) enzymatic activities. The properties of TPA as an LP inhibitor (via activation of PKC) and tumour promoter (inhibition of LP is a necessary step of tumour promotion) can be explained based on this suggestion.
authors.affiliation: Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, Russia.
authors.forename: N P
authors.initials: NP
authors.lastname: Palmina
authors.forename: E I
authors.initials: EI
authors.lastname: Pinzar
authors.forename: N V
authors.initials: NV
authors.lastname: Kurnakova
authors.forename: E B
authors.initials: EB
authors.lastname: Burlakova
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D004789:Enzyme Activation; D066298:In Vitro Techniques; D015227:Lipid Peroxidation / Q000187:drug effects*; D008054:Lipid Peroxides / Q000378:metabolism*; D010084:Oxidation-Reduction; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D008054:Lipid Peroxides; D011494:Protein Kinases; D013755:Tetradecanoylphorbol Acetate