Search results for "wistar"
showing 10 items of 1094 documents
Modulation of aflatoxin B1 carcinogenicity, genotoxicity and metabolism in rat liver by dietary carotenoids: evidence for a protective effect of CYP1…
1997
The effects of several carotenoids of vitamin A and of 3-methylcholanthrene have been tested on the initiation of hepatocarcinogenesis by aflatoxin B1, using the sequential protocol of Solt and Farber. AFB1-induced DNA single-strand breaks and AFB1-metabolism were also assessed. The P4501A inducer carotenoids (canthaxanthin, astaxanthin, beta-apo-8'-carotenal) and 3-methylcholanthrene reduce the carcinogenicity of AFB1, divert AFB1-metabolism into the less genotoxic aflatoxin M1 and reduce AFB1-induced DNA single-strand breaks: we conclude that these carotenoids exert their protective effect through the deviation of AFB1 metabolism towards detoxification pathways. beta-Carotene decreased AF…
Dietary carotenoids inhibit aflatoxin B1-induced liver preneoplastic foci and DNA damage in the rat: Role of the modulation of aflatoxin B1 metabolism
1998
To study the effects of carotenoids on the initiation of liver carcinogenesis by aflatoxin B1 (AFB1), male weanling rats were fed beta-carotene, beta-apo-8'-carotenal, canthaxanthin, astaxanthin or lycopene (300 mg/kg diet), or an excess of vitamin A (21000 RE/kg diet), or were injected i.p. with 3-methylcholanthrene (3-MC) (6 x 20 mg/kg body wt) before and during i.p. treatment with AFB1 (2 x 1 mg/kg body wt). The rats were later submitted to 2-acetylaminofluorene treatment and partial hepatectomy, and placental glutathione S-transferase-positive liver foci were detected and quantified. The in vivo effects of carotenoids or of 3-MC on AFB1-induced liver DNA damage were evaluated using diff…
Dietary lycopene decreases the initiation of liver preneoplastic foci by diethylnitrosamine in the rat
1997
To test whether carotenoids can modulate the initiation of liver preneoplasia by diethylnitrosamine (DEN) or by 2-nitropropane (2-NP) in a sequential protocol of hepatocarcinogenesis, male weanling rats were fed for three or four weeks (respectively) diets containing beta-carotene, canthaxanthin, astaxanthin, or lycopene (300 mg/kg diet) or an excess of vitamin A (15,000 retinol equivalents/kg diet) or were treated intraperitoneally with 3-methylcholanthrene. During this period, all rats were injected intraperitoneally with the initiator carcinogen, either 2-NP (6 times at 100 mg/kg body wt) or DEN (once at 100 mg/kg body wt). Three weeks after the termination of carotenoid or vitamin A fee…
Vitamin E deficiency induces liver nuclear factor-κB DNA-binding activity and changes in related genes
2005
The biological functions of vitamin E have been classically attributed to its property as a potent inhibitor of lipid peroxidation in cellular membranes. However, in 1991, Azzi's group first described that alpha-tocopherol inhibits smooth muscle cell proliferation in a protein kinase C (PKC)-dependent way, demonstrating a non-antioxidant cell signalling function for vitamin E. More recently, the capacity of alpha-tocopherol to modulate gene expression with the implication of different transcription factors, beyond its antioxidant properties, has also been established. This study was to determine the effect of vitamin E-deficiency on liver nuclear factor-kappa B (NF-kappaB) DNA-binding activ…
Formulation, process conditions, and biological evaluation of dairy mixed gels containing fava bean and milk proteins: Effect on protein retention in…
2019
International audience; Food formulation and process conditions can indirectly influence AA digestibility and bioavailability. Here we investigated the effects of formulation and process conditions used in the manufacture of novel blended dairy gels (called "mixed gels" here) containing fava bean (Vicia faba) globular proteins on both protein composition and metabolism when given to young rats. Three mixed dairy gels containing casein micelles and fava bean proteins were produced either by chemical acidification (A) with glucono-δ-lactone (GDL) or by lactic acid fermentation. Fermented gels containing casein and fava bean proteins were produced without (F) or with (FW) whey proteins. The AA…
Inhibition of Xanthine Oxidase by Phenolic Conjugates of Methylated Quinic Acid
2003
The caffeoyl conjugates of prenylhydroquinone glucoside and of quinic acid, either in the carboxyl-free or carboxymethyl forms, isolated from Phagnalon rupestre (Asteraceae), showed inhibitory activity on lipid peroxidation induced by Fe 2+/ascorbate and by CCl4/NADPH in rat liver microsomes, with IC50 values ranging from 3 to 11 microM. After having demonstrated their effect on the xanthine oxidase-regulated superoxide production, the active compounds were tested for the direct inhibition of this enzyme. Methylated dicaffeoylquinic conjugates competitively inhibited the enzyme and the highest potency was obtained for the 4,5-diester, with an IC50 value of 3.6 microM, nearly ten times lower…
Expression and differential localization of xenobiotic transporters in the rat olfactory neuro-epithelium.
2011
International audience; Transporters, such as multidrug resistance P-glycoproteins (MDR), multidrug resistance-related proteins (MRP) and organic anion transporters (OATs), are involved in xenobiotic metabolism, particularly the cellular uptake or efflux of xenobiotics (and endobiotics) or their metabolites. The olfactory epithelium is exposed to both inhaled xenobiotics and those coming from systemic circulation. This tissue has been described as a pathway for xenobiotics to the brain via olfactory perineural space. Thereby, olfactory transporters and xenobiotic metabolizing enzymes, dedicated to the inactivation and the elimination of xenobiotics, have been involved in the toxicological p…
A multi-generational study on low-dose BPA exposure in Wistar rats: Effects on maternal behavior, flavor intake and development
2012
Bisphenol A (BPA) is a common endocrine disruptor found as an environmental and food contaminant. It exerts both developmental and behavioral effects, mainly when exposure occurs in early life. The aim of this study was to determine the multi-generational effects of chronic, human-relevant low-dose exposure to BPA on development, maternal behavior and flavor preference in Wistar rats. BPA was orally administered at a daily dose of 5 mu g/kg body weight to FO pregnant dams from the first day of gestation (GD 1) until the last day of lactation (LD 21), and then to Fl offspring from weaning (PND 21) to adulthood (PND 100). F2 offspring were not exposed. Development and clinical signs of toxici…
Induction of cytochrome P450 and/or detoxication enzymes by various extracts or rosemary: description of specific patterns
2001
The ability of rosemary to modulate cytochrome P450 (CYP) and detoxication enzymes in rat liver was evaluated by comparing the effects of dried leaves and leaf extracts with different chemical compositions: essential oil (EO) containing monoterpenes, a dichloromethane extract (DCME) containing phenolic diterpenes and a water-soluble extract (WSE) containing phenolic compounds such as rosmarinic acid and flavonoids. Chemical analyses were done in order to characterize the composition of extracts. Male Wistar rats received the leaves or extracts of rosemary in their diet at 0.5% (w/w) for 2 weeks. The effects of such treatments were evaluated for CYP (1A, 2B, 2E1), glutathione S-transferase (…
Fibroblast growth factor-2 and its receptor expression in proliferating precursor cells of the subventricular zone in the adult rat brain
2008
Several findings have suggested the existence in the subventricular zone (SVZ) from sagittal sections of adult rat brain of a trophic mechanism, mediated by fibroblast growth factor-2 (FGF-2) and its multiple high-affinity FGF receptors (FGFRs), regulating neurogenesis mainly by controlling precursor cell proliferation. However, no clear data are available on the expression of FGF-2 and FGFRs in proliferating precursor cells of the SVZ. To address these questions we examined FGF-2 mRNA and its FGFR mRNA expression in proliferating precursor cells of the SVZ by using a double labeling procedure, combining in situ hybridization for FGF-2 and its FGFR mRNA with immunohistochemistry for bromode…