Search results for "Glutathion"
showing 10 items of 744 documents
Mandarin Juice Improves the Antioxidant Status of Hypercholesterolemic Children
2008
Background: Oxidative stress has been linked to such degenerative diseases as atherosclerosis, and it has been suggested that increased dietary intake of antioxidants may reduce its progression. Objective: To determine the effect of mandarin juice consumption on biomarkers related to oxidative stress in hypercholesterolemic children. Materials and Methods: The diet of 48 children with plasma cholesterol >200 mg/dL and low-density lipoprotein cholesterol >130 mg/dL was supplemented for 28 days with 500 mL/day of pure (100%) mandarin juice (Citrus clementina Hort. ex Tan.). The composition of the mandarin juice was analyzed, and its antioxidant antiradical activity was evaluated in vitro. Mal…
Bacteria-Derived Compatible Solutes Ectoine and 5α-Hydroxyectoine Act as Intestinal Barrier Stabilizers to Ameliorate Experimental Inflammatory Bowel…
2015
Earlier studies showed that the compatible solute ectoine (1) given prophylactically before induction of colitis by 2,4,6-trinitrobenzenesulfonic acid (TNBS) in rats prevented histological changes induced in the colon and the associated rise in inflammatory mediators. This study was therefore conducted to investigate whether ectoine (1) and its 5α-hydroxy derivative (2) would also be effective in treating an already established condition. Two days after inducing colitis in rats by instilling TNBS/alcohol in the colon, animals were treated orally once daily for 1 week with either 1 or 2 (50, 100, 300 mg/kg). Twenty-four hours after the last drug administration rats were sacrificed. Ulcerativ…
Oxidation of tienilic acid by human yeast-expressed cytochromes P-450 2C8, 2C9, 2C18 and 2C19. Evidence that this drug is a mechanism-based inhibitor…
1996
Oxidation of tienilic acid by human cytochromes P-450 (CYP) 2C9, 2C18, 2C8 and 2C19 was studied using recombinant enzymes expressed in yeast. CYP 2C9 was the best catalyst for 5-hydroxylation of tienilic acid (K(m) = 5 +/- 1 microM, kcat = 1.7 +/- 0.2 min-1), 30-fold more potent in terms of kcat/K(m) than CYP 2C18 (K(m) = 150 +/- 15 microM, kcat = 1.8 +/- 0.2 min-1) and 300-fold more potent than CYP 2C8 (K(m) = 145 +/- 15 microM, kcat = 0.2 +/- 0.1 min-1). CYP 2C19 was unable to catalyze this hydroxylation under our experimental conditions. During this study, a marked effect of the ionic strength on the activities (hydroxylations of tienilic acid and tolbutamide) of these cytochromes P-450 …
Beneficial effects of dithiothreitol on relative levels of glutathione S-transferase activity and thiols in oocytes, and cell number, DNA fragmentati…
2006
We analyzed the effect of in vitro aging of mouse oocytes in the presence of dithiothreitol (DTT) on relative levels of glutathione S-transferase (GST) activity and thiols in oocytes, and cell number, DNA fragmentation and cellular allocation to the inner cell mass (ICM) and trophectoderm (TE) lineage at the blastocyst stage. Ovulated oocytes from gonadotropin primed hybrid female mice of 6-8 weeks of age were aged in vitro in the presence of 0, 5, 50, or 500 microM DTT for 6 hr prior to insemination. Relative levels of GST activity and thiols in oocytes were determined by confocal laser scanning microscopy, DNA fragmentation using a single-step TUNEL method, and cell allocation to the ICM …
Coffee and its chemopreventive components Kahweol and Cafestol increase the activity of O6-methylguanine-DNA methyltransferase in rat liver—compariso…
2003
Abstract A lower rate of colon cancer was observed in consumers of coffee with a high content of the diterpenes Kahweol and Cafestol (K/C). In animal models, K/C have been found to protect against the mutagenic/carcinogenic effects of compounds such as 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), aflatoxin B1, and 7,12-dimethylbenz[a]anthracene. Thus far, such chemoprotection by K/C has been attributed to modifications of xenobiotic metabolism, e.g. enhanced detoxification by UDP-glucuronosyltransferase (UDPGT) and/or glutathione transferase (GST). In the present study, we investigated the potential of several coffee-related treatments (K/C [1:1], Cafestol-alone, Turkish coffee) …
Properties of the microsomal and cytosolic glutathione transferases involved in hexachloro-1:3-butadiene conjugation
1989
Hexachloro-1,3-butadiene (HCBD) is a substrate for the hepatic microsomal glutathione transferases and is metabolised at higher rates by these enzymes than their cytosolic counterparts. Conjugation reactions catalysed by the microsomal and cytosolic transferases have been studied and characterized using this substrate and 1-chloro-2,4-dinitrobenzene (CDNB). In rat liver microsomes the Km values for HCBD and CDNB were 0.91 and 0.012 mM and in cytosol 0.51 and 0.10 mM respectively. Vmax values for HCBD were 1.39 and 0.35 nmol conjugate formed/min/mg protein for microsomes and cytosol respectively. In microsomal systems HCBD was a potent competitive inhibitor of the metabolism of CDNB with a K…
Selenium, Copper, and Zinc Indices of Nutritional Status : Influence of Sex and Season on Reference Values
2000
The objective was to estimate the possible influence of season or season and sex on the selenium, glutathione peroxidase (GSH-Px), copper, zinc, and superoxide dismutase (SOD) values in plasma with a view to establishing reference values. For this purpose, 55 healthy volunteers (36 women and 19 men) were selected and their whole-blood samples were collected four times a year at the beginning of each season. In the population as a whole, no statistically significant seasonal differences were detected in copper, selenium, and GSH-Px values in plasma, whereas zinc and SOD values in plasma depended on the season. In general, the variability was higher among the women. In view of the differences…
Induction of rat liver microsomal epoxide hydrolase by its endogenous substrate 16α, 17α-epoxyestra-1,3,5-trien-3-ol
1995
1. The influence of the endogenous steroid epoxides 16 alpha, 17 alpha-epoxyestra-1,3,5(10)-trien-3-ol (estroxide) and 16 alpha, 17 alpha-expoxiandrost-4-en-3-one (androstene oxide) and their metabolic precursors estra-1,3,5(10), 16-tetraen-3-ol (estratetraenol) and androsta-4, 16-dien-3-one (androstadienone) on the specific activities of hepatic microsomal and soluble epoxide hydrolase, glutathione S-transferase, dihydrodiol dehydrogenase, and 7-ethoxycoumarin deethylase was investigated in the male Sprague-Dawley rat. 2. Both estroxide and estratetraenol induced microsomal epoxide hydrolase activity towards styrene oxide and estroxide itself 2-2.5-fold and glutathione conjugation of 1-chl…
Stock-specific variation of trophic position, diet and environmental stress markers in Atlantic salmon Salmo salar during feeding migrations in the B…
2012
This study investigated stock-specific variation in selected ecophysiological variables during the feeding migrations of Atlantic salmon Salmo salar in the Baltic Sea. Oxidative stress biomarkers and EROD (ethoxyresorufin-O-deethylase, Cyp1A enzyme) activity were used as indicators of possible environmental stress and stable isotopes as determinants of diet and trophic position. Latvian S. salar stocks Daugava and Gauja had distinct stable-isotope signatures compared to the other stocks, indicating differences in migration patterns, residency or arrival times, or dietary specialization among stocks. Salmo salar originating from Daugava and Gauja also had lower catalase enzyme activity than …
Calcium overload increases oxidative stress in old rat gastrocnemius muscle
2005
International audience; In order to challenge in vivo muscle Ca2+ homeostasis and analyze consequences on mitochondrial H2O2 release (MHR) and sarcopenia, we injected Ca2+ ionophore A23187 (200 µg/kg, ip) in adult and old rats and measured gastrocnemius mass and mitochondrial Ca2+ content (MCC) using radioactive Ca2+ 48 h after injection. In a second experiment performed in old rats, we measured isocitrate dehydrogenase (ICDH) activity as an index of MCC, MHR, mitochondrial respiration, citrate synthase, COX and antioxydant enzyme activities 24 h after a 150 µg/kg injection. In adult rats, muscle mass and MCC were unchanged by A23187. In old rats, MCC increased 24 h after injection as refle…