Search results for "Reductases"
showing 10 items of 276 documents
Conversion of biliverdin to bilirubin by biliverdin reductase contributes to endothelial cell protection by heme oxygenase-1—evidence for direct and …
2009
Heme oxygenase-1 (HO-1) is highly protective in various pathophysiological states such as cardiovascular and neurodegenerative diseases. HO-1-derived bilirubin is an efficient scavenger of reactive oxygen and nitrogen species (RONS). It remains to determine whether conversion of biliverdin to bilirubin is an essential step for HO-1-conferred protection of endothelial cells. RONS scavenging activities of biliverdin versus bilirubin were assessed by different RONS generating systems and detection techniques. We also silenced the biliverdin reductase (BVR) or HO-1 gene in cultured primary human endothelial cells (HUVECs) and measured the effect on RONS formation upon stimulation with lipopolys…
Evaluation of acyl coenzyme A oxidase (Aox) isozyme function in the n- alkane-assimilating yeast Yarrowia lipolytica
1999
ABSTRACT We have identified five acyl coenzyme A (CoA) oxidase isozymes (Aox1 through Aox5) in the n -alkane-assimilating yeast Yarrowia lipolytica , encoded by the POX1 through POX5 genes. The physiological function of these oxidases has been investigated by gene disruption. Single, double, triple, and quadruple disruptants were constructed. Global Aox activity was determined as a function of time after induction and of substrate chain length. Single null mutations did not affect growth but affected the chain length preference of acyl-CoA oxidase activity, as evidenced by a chain length specificity for Aox2 and Aox3. Aox2 was shown to be a long-chain acyl-CoA oxidase and Aox3 was found to …
The influence of phase transitions in phosphatidylethanolamine models on the activity of violaxanthin de-epoxidase
2008
In the present study, the influence of the phospholipid phase state on the activity of the xanthophyll cycle enzyme violaxanthin de-epoxidase (VDE) was analyzed using different phosphatidylethanolamine species as model lipids. By using (31)P NMR spectroscopy, differential scanning calorimetry and temperature dependent enzyme assays, VDE activity could directly be related to the lipid structures the protein is associated with. Our results show that the gel (L beta) to liquid-crystalline (L alpha) phase transition in these single lipid component systems strongly enhances both the solubilization of the xanthophyll cycle pigment violaxanthin in the membrane and the activity of the VDE. This pha…
Circumdatin H, a new inhibitor of mitochondrial NADH oxidase, from Aspergillus ochraceus
2005
Circumdatin H (1), a new alkaloid from the culture broth of Aspergillus ochraceus, has been isolated, together with a known circumdatin, circumdatin E (2) and other known compounds: flavacol (3) and stephacidin A (4). The structure of 1 was established on the basis of chemical and spectral evidence. All of these alkaloids showed biological activity as inhibitors of the mammalian mitochondrial respiratory chain.
Synthesis of N-diisopropyl phosphoryl benzyl-tetrahydroisoquinoline, a new class of mitochondrial complexes I and III inhibitors
2000
The synthesis of N-(O,O-diisopropylphosphoryl)-benzyltetrahydroisoquinoline (3) has been achieved in a 'one pot' procedure from imine (2) and diisopropyl-phosphorochloridate (1) generated in situ (POCl3 + iPrOH). Compound 3 is the first benzyltetrahydroisoquinoline derivative found to be a potent inhibitor of mitochondrial complexes I and III, and therefore it opens a new perspective with this series of compounds as they can be considered as new class of antitumor agents.
Polyalthidin: New Prenylated Benzopyran Inhibitor of the Mammalian Mitochondrial Respiratory Chain
1996
Polyalthidin (3), a new benzopyran derivative, was isolated from the stem bark of Polyalthia cerasoides. Its structure was established on the basis of chemical and spectral evidence. Polyalthidin has showed potent biological activity as an inhibitor of the mammalian mitochondrial respiratory chain.
Dual disruption of aldehyde dehydrogenases 1 and 3 promotes functional changes in the glutathione redox system and enhances chemosensitivity in nonsm…
2020
AbstractAldehyde dehydrogenases (ALDHs) are multifunctional enzymes that oxidize diverse endogenous and exogenous aldehydes. We conducted a meta-analysis based on The Cancer Genome Atlas and Gene Expression Omnibus data and detected genetic alterations in ALDH1A1, ALDH1A3, or ALDH3A1, 86% of which were gene amplification or mRNA upregulation, in 31% of nonsmall cell lung cancers (NSCLCs). The expression of these isoenzymes impacted chemoresistance and shortened survival times in patients. We hypothesized that these enzymes provide an oxidative advantage for the persistence of NSCLC. To test this hypothesis, we used genetic and pharmacological approaches with DIMATE, an irreversible inhibito…
Mediterranean Diet Decreases the Initiation of Use of Vitamin K Epoxide Reductase Inhibitors and Their Associated Cardiovascular Risk: A Randomized C…
2020
Our aim is to assess whether following a Mediterranean Diet (MedDiet) decreases the risk of initiating antithrombotic therapies and the cardiovascular risk associated with its use in older individuals at high cardiovascular risk. We evaluate whether participants of the PREvenció
Effect of Eight Weeks' Physical Training on Muscle and Connective Tissue of the M. Vastus Lateralis in 69-year-old Men and Women
1977
Five one-hour exercise periods a week for 8 weeks included walking-jogging, swimming, gymnastics and ballgames for 26 healthy male and female 69-year-old pensioners. The mean maximal oxygen uptake of the men increased from 28.9 ml-kg-1-min-1 before training to 32.0 ml-kg-1-min-1 after training and for the women from 27.9 to 31.3 ml-kg-1-min-1. Muscle malate dehydrogenase activity was increased while that for lactate dehydrogenase decreased or remained the same. The activity of these enzymes was higher in the male both before and after training when compared with the female. However, the percentage number of slow twitch muscle fibers was nearly the same in both groups. Prolyl hydroxylase act…