Further Experiments on Lipid Peroxidation in Transplanted and Experimental Hepatomas

Autor: Fiorella Biasi, Maria E. Biocca, Rosa A. Canuto, Anna Maria Bassi, Margherita Ferro, Mario U. Dianzani, Renato Garcea, Maria A. Rossi, G Poli, Giovanni Cecchini
Rok vydání: 1984
Předmět:
Male
Antioxidant
hepatomas
040301 veterinary sciences
medicine.medical_treatment
Glutathione reductase
Toxicology
030226 pharmacology & pharmacy
Pathology and Forensic Medicine
0403 veterinary science
Lipid peroxidation
03 medical and health sciences
chemistry.chemical_compound
Cytosol
Liver Neoplasms
Experimental
0302 clinical medicine
Cytochrome P-450 Enzyme System
lipid peroxidation
Tumor Cells
Cultured
medicine
Animals
Diethylnitrosamine
Rats
Wistar
Gamma-glutamyltransferase
Molecular Biology
Carcinogen
Glutathione Transferase
chemistry.chemical_classification
Glutathione Peroxidase
biology
Glutathione peroxidase
gamma-Glutamyltransferase
04 agricultural and veterinary sciences
Cell Biology
Glutathione
Metabolism
Rats
Disease Models
Animal
Glutathione Reductase
chemistry
Biochemistry
Carcinogens
Microsomes
Liver
biology.protein
Precancerous Conditions
Neoplasm Transplantation
Aminopyrine N-Demethylase
Zdroj: Toxicologic Pathology. 12:189-199
ISSN: 1533-1601
0192-6233
DOI: 10.1177/019262338401200213
Popis: The results of experiments on the subject of lipid peroxidation in hepatomas are described. It is now clear that lipid peroxidation is strongly decreased in most highly dedifferentiated hepatomas. It seems evident that the extent of the decline is strictly related to the degree of dedifferentiation. The model of diethylnitrosamine carcinogenesis, according to the method by Soh, Medline and Farber, has been now adopted to study the stages of carcinogenesis. It was shown that a net decline in lipid peroxidation occurs as early as at the stage of reversible nodules and progresses until the development of clear hepatomas. This change is practically simultaneous with a decline in the efficiency of the enzymes of the drug metabolizing system and in the content of cytochrome P450. Glutathione content and metabolism show also important changes. In fact, a dramatic increase in gamma-glutamyl-transpeptidase takes place very early during carcinogenesis, and is responsible for large decline in total glutathione during incubation of the homogenates. Glutathione peroxidase activity, on the contrary, is decreased, whereas glutathione reductase does not show significant changes. The supernatant of highly anaplastic tumors inhibits lipid peroxidation in normal liver homogenates, suggesting the presence of substances provided with antioxidant properties. These cannot be, however, related to a higher glutathione content. Supernatants from early nodules seem to be unable to block lipid peroxidation in normal liver homogenates. Preliminary experiments done to study the aldehyde pattern produced during lipid peroxidation, both in hepatomas and in nodules, confirm the presence of very poor lipid peroxidation and possibly of different peroxidation kinetics.
Databáze: OpenAIRE
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