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The 68K protease has beta-secretase-like activity for lymphocyte precursor protein but not for brain substrate.

https://arctichealth.org/en/permalink/ahliterature199515
Source
Neuroreport. 2000 Feb 7;11(2):373-7
Publication Type
Article
Date
Feb-7-2000
Author
A. Matsumoto
Author Affiliation
Department of Radiation Biophysics and Genetics, Kobe University School of Medicine, Japan.
Source
Neuroreport. 2000 Feb 7;11(2):373-7
Date
Feb-7-2000
Language
English
Publication Type
Article
Keywords
Aged
Aged, 80 and over
Alzheimer Disease - enzymology
Amino Acid Sequence
Amyloid Precursor Protein Secretases
Amyloid beta-Protein Precursor - metabolism
Aspartic Acid Endopeptidases - metabolism
Blotting, Western
Cells, Cultured
Cerebral Cortex - enzymology
Chondroitin ABC Lyase - metabolism
Endopeptidases
Female
Humans
Isoenzymes - metabolism
Lymphocytes - cytology - enzymology
Male
Middle Aged
Molecular Sequence Data
Organ Specificity
Peptide Fragments - chemistry
Polysaccharide-Lyases - metabolism
Protein Processing, Post-Translational
Sequence Analysis, Protein
Serine Endopeptidases - metabolism
Substrate Specificity
Abstract
Processing and metabolism of beta-amyloid precursor protein (APP) and generation of a variety of beta-amyloid (Abeta) peptides in the human brain is essentially associated with pathophysiology of Alzheimer's disease (AD). APP degradation activity of the 68 kDa serine protease, which was originally prepared from familial AD lymphoblastoid cells and harbors beta-secretase-like activity, was analyzed by Western blot using anti Abeta 1/40 antibody and anti APP cytoplasmic domain (CT) antibody. Native lymphocyte APP (LAPP) prepared from normal or AD-derived lymphoblastoid cells was degraded by the protease, generating a 16 kDa Abeta-bearing C-terminal fragment of APP. N-terminal amino acid sequencing of the fragment indicated that the protease cleaves LAPP at the Abeta-N-terminus. When the LAPP was treated with chondroitinase ABC prior to proteolysis, the activity to generate the fragment was inhibited, but pretreatment with heparitinase resulted in no effect. Native hippocampal APP prepared from normal brain, however, did not generate the 16 kDa peptide by the protease treatment. These results suggest that the process of APP degradation and Abeta-peptides generation, including beta-secretase activity, is associated with tissue specificity of both APP substrate and proteases. They also indicate that sulfated glycoconjugates attached to a portion of APP isoforms may play a role as a molecular determinant in the proteolysis.
PubMed ID
10674489 View in PubMed
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[Activity of enzymes of tricarboxylic and pentose-phosphate cycles in dog brain with myocardial infarction]

https://arctichealth.org/en/permalink/ahliterature56070
Source
Ukr Biokhim Zh. 1977 May-Jun;49(3):51-4
Publication Type
Article
Author
M M Zanozdra
Iu V Khmelevs'kii
Source
Ukr Biokhim Zh. 1977 May-Jun;49(3):51-4
Language
Ukrainian
Publication Type
Article
Keywords
Animals
Brain - enzymology
Cerebellum - enzymology
Cerebral Cortex - enzymology
Citric Acid Cycle
Coronary Vessels
Dogs
English Abstract
Glucosephosphate Dehydrogenase - metabolism
Hypoxia, Brain - enzymology
Ketoglutarate Dehydrogenase Complex - metabolism
Medulla Oblongata - enzymology
Mitochondria - enzymology
Myocardial Infarction - enzymology
Pentosephosphates - metabolism
Succinate Dehydrogenase - metabolism
Transaldolase - metabolism
Abstract
Under conditions of experimental myocardium infarction caused in dogs by ligation of the anterior descending branch of the left coronary artery, the activity of alpha-ketoglutarate dehydrogenase and succinate dehydrogenase in mitochondria of the cortex, cerebellum and medulla ablongata lowers most intensively on the first and fifth day after the appearance of acute myocardium infarction. Activation of the most important enzymes of the pentose-phosphate cycle (glucose-6-phosphate dehydrogenase and transketolase) which is clearly pronounced on the fifth day is observed in the mentioned sections. In the authors' opinions the above changes in the activity of the enzymes are due to the brain hypoxia which may be the main reason of disturbance in the function of the central nervous system under this disease.
PubMed ID
888227 View in PubMed
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The effect of age on phosphatidylinositol kinase, phosphatidylinositol phosphate kinase and diacylglycerol kinase activities in rat brain cortex.

https://arctichealth.org/en/permalink/ahliterature11631
Source
Growth Dev Aging. 1994;58(2):67-73
Publication Type
Article
Date
1994
Author
J. Bothmer
M. Mommers
M. Markerink
J. Jolles
Author Affiliation
Department of Neuropsychology and Psychobiology, University of Limburg, Maastricht, The Netherlands.
Source
Growth Dev Aging. 1994;58(2):67-73
Date
1994
Language
English
Publication Type
Article
Keywords
1-Phosphatidylinositol 4-Kinase
Aging - metabolism
Animals
Cerebral Cortex - enzymology - ultrastructure
Diacylglycerol Kinase
Male
Phosphotransferases (Alcohol Group Acceptor) - metabolism
Rats
Rats, Inbred BN
Subcellular Fractions - enzymology
Abstract
A previous study, in which a lysed fraction was used with endogenous phospholipids as substrate, revealed age-related changes in PA and PIP2 formation but not in PIP formation (Bothmer et al., Neurochem. Int. 21, 223-228, 1992). To rule out the influence of substrate availability in the present study, the effect of age on PI kinase, PIP kinase and DAG kinase activities was studied with exogenous phospholipids as substrate in the cerebral cortex from 8-month-old, 14-month-old and 26-month-old Brown Norway rats. PI kinase activity was predominantly located in a tight membrane-bound protein fraction, DAG kinase activity in cytosolic and loosely membrane-bound protein fractions, and PIP kinase activity was present in all three protein preparations. The effects of age were limited to a small increase in kinase activity in the tight membrane-bound protein fraction in 14-month-old and 26-month-old rats compared to 8-month-old rats, and a 10% decrease in PIP kinase activity in the cytosolic protein fraction in 14-month-old and 26-month-old rats compared to 8-month-old rats. DAG kinase activity showed no age-related changes. In conclusion, one should take care in comparing rat aging with human aging as PI kinase activity shows an age-related decline in human brain cortex (Jolles et al., J. Neurochem. 58, 2326-2329, 1992). Furthermore, previously reported decreases in PA formation rates in rat brain are probably not due to changes in DAG kinase itself but to changes in DAG availability, although further experimental evidence is needed to confirm this conclusion.
PubMed ID
7928021 View in PubMed
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[Some peculiarities of the electric reactions, submicroscopic organization and enzymatic activity of the cerebral cortex (visual region) during stimulation of the reticular formation of the stem]

https://arctichealth.org/en/permalink/ahliterature51567
Source
Fiziol Zh. 1966 Mar-Apr;12(2):168-76
Publication Type
Article

[Structural and functional state of microsomal membranes in the rat brain cortex during long-term ethanol consumption]

https://arctichealth.org/en/permalink/ahliterature9561
Source
Ukr Biokhim Zh. 2003 Jul-Aug;75(4):97-100
Publication Type
Article
Author
D O Mishchuk
A A Kaplia
Author Affiliation
Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv, Ukraine.
Source
Ukr Biokhim Zh. 2003 Jul-Aug;75(4):97-100
Language
Russian
Publication Type
Article
Keywords
Administration, Oral
Alcoholism - enzymology - physiopathology
Anilino Naphthalenesulfonates - pharmacology
Animals
Cell Membrane - enzymology - physiology
Cerebral Cortex - enzymology - physiology
Disease Models, Animal
English Abstract
Ethanol - administration & dosage
Female
Microsomes - enzymology - physiology
Na(+)-K(+)-Exchanging ATPase - metabolism
Rats
Spectrometry, Fluorescence
Abstract
The range of the Na+, K(+)-ATPase functional stability in microsomal fraction of rat brain cortex under long-term chronic ethanol (15%, v/v) consumption was ascertained. The enzyme activity decreased only after 15 months of alcoholisation on the background of the stable structural membrane characteristics (on the basis of the intrinsic and 1-anilinonaphthalene-8-sulfonate fluorescence parameters) and SH-content in postmitochondrial supernatant. The cellular homeostatic mechanisms under ethanol effect are discussed.
PubMed ID
14681981 View in PubMed
Less detail