Biomaterial Database

Effects of amyloid-beta peptides on hydrogen peroxide-metabolizing enzymes in rat brain in vivo. 2008

Yury G Kaminsky, and Elena A Kosenko

Institute of Theoretical and Experimental Biophysics, RAS, Pushchino, Russia. kaminsky@iteb.ru

Amyloid-beta (Abeta) peptides are components of senile plaques initiating degeneration of brain neurons in Alzheimer's disease. They increase reactive oxygen species generation that may exceed the defensive capacity of cells. To test the hypothesis, this study investigated the in vivo effects of Abeta peptides on mitochondrial and non-mitochondrial enzymic sources of reactive oxygen species and antioxidant enzymes in rat brain. Continuous intracerebroventricular infusion of both Abeta(25-35) and Abeta(1-40) for up to 14 days stimulated the hydrogen peroxide (H2O2) generation in isolated neocortex mitochondria. Infusion of Abeta(1-40) led to an increase in Mn-superoxide dismutase activity and a decrease in activities of catalase and glutathione peroxidase in mitochondria, to elevation of activities of Cu,Zn-superoxide dismutase and aldehyde oxidase, forwarded the conversion of xanthine dehydrogenase to xanthine oxidase and corresponding increase in the rate of H2O2 formation in the cytosol. Thus, Abeta peptides increase H2O2-formation and H2O2-forming enzyme activities and inhibit H2O2-consuming enzyme activities in mitochondria and cytosol in vivo. These studies suggest that disbalance between H2O2-generating and H2O2-metabolizing enzyme activities can contribute to oxidative stress underlying neurodegeneration and neuronal death in Alzheimer's disease.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008928	Mitochondria	Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)	Mitochondrial Contraction,Mitochondrion,Contraction, Mitochondrial,Contractions, Mitochondrial,Mitochondrial Contractions
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D003600	Cytosol	Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.	Cytosols
D006861	Hydrogen Peroxide	A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials.	Hydrogen Peroxide (H2O2),Hydroperoxide,Oxydol,Perhydrol,Superoxol,Peroxide, Hydrogen
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000975	Antioxidants	Naturally occurring or synthetic substances that inhibit or retard oxidation reactions. They counteract the damaging effects of oxidation in animal tissues.	Anti-Oxidant,Antioxidant,Antioxidant Activity,Endogenous Antioxidant,Endogenous Antioxidants,Anti-Oxidant Effect,Anti-Oxidant Effects,Anti-Oxidants,Antioxidant Effect,Antioxidant Effects,Activity, Antioxidant,Anti Oxidant,Anti Oxidant Effect,Anti Oxidant Effects,Anti Oxidants,Antioxidant, Endogenous,Antioxidants, Endogenous
D013844	Thiazoles	Heterocyclic compounds where the ring system is composed of three CARBON atoms, a SULFUR and NITROGEN atoms.	Thiazole
D016229	Amyloid beta-Peptides	Peptides generated from AMYLOID BETA-PEPTIDES PRECURSOR. An amyloid fibrillar form of these peptides is the major component of amyloid plaques found in individuals with Alzheimer's disease and in aged individuals with trisomy 21 (DOWN SYNDROME). The peptide is found predominantly in the nervous system, but there have been reports of its presence in non-neural tissue.	Alzheimer beta-Protein,Amyloid Protein A4,Amyloid beta-Peptide,Amyloid beta-Protein,beta Amyloid,beta-Amyloid Protein,Alzheimer's ABP,Alzheimer's Amyloid Fibril Protein,Amyloid AD-AP,Amyloid Fibril Protein, Alzheimer's,Amyloid beta-Proteins,ABP, Alzheimer's,AD-AP, Amyloid,Alzheimer ABP,Alzheimer beta Protein,Alzheimers ABP,Amyloid AD AP,Amyloid beta Peptide,Amyloid beta Peptides,Amyloid beta Protein,Amyloid beta Proteins,Amyloid, beta,Protein A4, Amyloid,Protein, beta-Amyloid,beta Amyloid Protein,beta-Peptide, Amyloid,beta-Peptides, Amyloid,beta-Protein, Alzheimer,beta-Protein, Amyloid,beta-Proteins, Amyloid