RESUMO
The dynamics and periodicity of LPO processes in the nuclei and chromatin were detected during regenerative processes in mouse liver. LPO processes were enhanced in transcriptionally active and replicating chromatin. Phosphatidylcholine, phosphatidylinositol, esterified cholesterol, and free fatty acids were maximally oxidized during active transcription, and cardiolipin was oxidized during active replication. These processes were accompanied by periodical changes in activity of antioxidant enzymes. High activity of SOD during transcriptional activity of liver cells was typical for nuclear matrix-attached chromatin, but this parameter decreased during replication. Catalase activity significantly increased in the fractions of high salt chromatin and nuclear matrix-bound chromatin during replication.
Assuntos
Núcleo Celular/metabolismo , Hepatócitos/fisiologia , Peroxidação de Lipídeos , Fosfolipídeos/metabolismo , Animais , Animais não Endogâmicos , Proliferação de Células , Cromatina/metabolismo , Replicação do DNA , Hepatectomia , Fígado/citologia , Fígado/fisiologia , Regeneração Hepática , Camundongos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Transcrição GênicaRESUMO
Hydrogen peroxide stimulates apoptosis of zymosan-activated rat peritoneal macrophages. Phosphoinositide cycle modifiers enhance the proapoptotic effect of H(2)O(2) in a concentration of 1 mM and necrosis-stimulating effect of H(2)O(2) in a concentration of 10 mM. Disorders in phosphoinositide metabolism and impaired reaction of the cell to proinflammatory agents are the cause of programmed cell death. Rejection of defective cells can be realized via variation of H(2)O(2) concentration.