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Evaluation of Cytochrome P450 Gene Expression as Physiological Pollution Biomarkers in Broiler Chickens Fed Silver Nanoparticles
2020
Arabiyan, Elnaz | Hashemi, Seyed Reza | Yamchi, Ahad | Davoodi, Homa | Rostami, Sharif
BACKGROUND: Nowadays, researchers are converted silver to nanometer dimensions and using nanotechnology to achieve suitable performance and preserve the poultry health and they are used silver nanoparticles are used for poultry nutrition as a nutritional supplement. On the other hand, at the molecular level no complete reports in poultry breeding have been provided. OBJECTIVES: This study was conducted to evaluate cytochrome P450 gene expression in broiler chickens fed with silver nanoparticles. METHODS: This experiment a completely randomized design with 450 single-day Cobb 500 broiler chicks was divided into five treatments and six replications (15 birds in each replicate). Chickens were fed with (1) control (basal diet), (2) basal diet containing 1% zeolite, (3) basal diet containing 1% of zeolite-coated with 0.5% silver nanoparticles, (4) Basal diet containing with 0.15% organic acids and (5) Basal diet containing 1% of zeolite-coated with 0.5% of silver nanoparticles and 0.15% organic acids in with or without heat stress condition. RESULTS: Results demonstrated the level of expression of cytochrome P450 in broilers fed zeolite (Z) in the 21st day of experiment, silver nanoparticles coated with zeolite in combination with organic acid (NSOA) in 42nd day without heat stress condition and silver nanoparticles coated with zeolite (NS) in day 42 with heat stress condition in intestine and liver had significant increase in expression in comparison with control (C) treatment (P<0.05). CONCLUSIONS: In conclusion, result showed that zeolite and silver nanoparticles were identified as inorganic, chemical and exogenous substances in liver and intestine and up-regulated expression of pollution biomarkers genes. Whereas this effect is not identified in organic acid.
Afficher plus [+] Moins [-]Effect of cytochrome P450 inhibition on toxicity of diclofenac in chickens: Unravelling toxicity in Gyps vultures
2022
Locke,Sara | Naidoo,Vinny | Hassan,Ibrahim | Duncan,Neil
Diclofenac was responsible for the decimation of Gyps vulture species on the Indian subcontinent during the 1980s and 1990s. Gyps vultures are extremely sensitive (the lethal dose 50 [LD50] ~ 0.1 mg/kg - 0.2 mg/kg), with toxicity appearing to be linked to metabolic deficiency, demonstrated by the long T1/2 (~12 h - 17 h). This is in striking comparison to the domestic chicken (Gallus gallus domesticus), in which the LD50 is ~10 mg/kg and the T1/2 is ~1 h. The phase 1 cytochrome P450 (CYP) 2C subfamily has been cited as a possible reason for metabolic deficiency. The aim of this study was to determine if CYP2C9 homolog pharmacogenomic differences amongst avian species is driving diclofenac toxicity in Gyps vultures. We exposed each of 10 CYP-inhibited test group chickens to a unique dose of diclofenac (as per the Organisation for Economic Co-operation and Development [OECD] toxicity testing guidelines) and compared the toxicity and pharmacokinetic results to control group birds that received no CYP inhibitor. Although no differences were noted in the LD50 values for each group (11.92 mg/kg in the CYP-inhibited test group and 11.58 mg/kg in the control group), the pharmacokinetic profile of the test group was suggestive of partial inhibition of CYP metabolism. Evaluation of the metabolite peaks produced also suggested partial metabolic inhibition in test group birds, as they produced lower amounts of metabolites for one of the three peaks demonstrated and had higher diclofenac exposure. This pilot study supports the hypothesis that CYP metabolism is varied amongst bird species and may explain the higher resilience to diclofenac in the chicken versus vultures.
Afficher plus [+] Moins [-]Effect of cytochrome P450 inhibition on toxicity of diclofenac in chickens: Unravelling toxicity in Gyps vultures
2022
Sara Locke | Vinny Naidoo | Ibrahim Hassan | Neil Duncan
Diclofenac was responsible for the decimation of Gyps vulture species on the Indian subcontinent during the 1980s and 1990s. Gyps vultures are extremely sensitive (the lethal dose 50 [LD50] ~ 0.1 mg/kg – 0.2 mg/kg), with toxicity appearing to be linked to metabolic deficiency, demonstrated by the long T1/2 (~12 h – 17 h). This is in striking comparison to the domestic chicken (Gallus gallus domesticus), in which the LD50 is ~10 mg/kg and the T1/2 is ~1 h. The phase 1 cytochrome P450 (CYP) 2C subfamily has been cited as a possible reason for metabolic deficiency. The aim of this study was to determine if CYP2C9 homolog pharmacogenomic differences amongst avian species is driving diclofenac toxicity in Gyps vultures. We exposed each of 10 CYP-inhibited test group chickens to a unique dose of diclofenac (as per the Organisation for Economic Co-operation and Development [OECD] toxicity testing guidelines) and compared the toxicity and pharmacokinetic results to control group birds that received no CYP inhibitor. Although no differences were noted in the LD50 values for each group (11.92 mg/kg in the CYP-inhibited test group and 11.58 mg/kg in the control group), the pharmacokinetic profile of the test group was suggestive of partial inhibition of CYP metabolism. Evaluation of the metabolite peaks produced also suggested partial metabolic inhibition in test group birds, as they produced lower amounts of metabolites for one of the three peaks demonstrated and had higher diclofenac exposure. This pilot study supports the hypothesis that CYP metabolism is varied amongst bird species and may explain the higher resilience to diclofenac in the chicken versus vultures.
Afficher plus [+] Moins [-]Effect of membrane lipid peroxidation on rat liver microsomal enzyme activity
Park, S.Y.;Cho, J.H.(Chonbuk National University, Jeonju, Republic of Korea)E-mail:sypark@chonbuk.ac.kr
The effects of membrane lipid peroxidation and retinyl palmitate on rat liver microsomal functions were investigated in vitro. Rat liver homogenates exposed to oxygen tension for 0, 3, 6, 9 or12 hours and lipid peroxidation levels were evaluated by the measurements of fluorescence intensity, malondialdehyde (MDA) and retinyl palmitate. The fluorescence intensity of homogenates and microsomes were elevated and retinyl palmitate concentrations were decreased. But the concentration of MDA was not affected to exposure time. Therefore, fluorescence intensity and retinyl palmitate concentration were used to analyze the correlation between lipid peroxidation and microsomal functions.
Afficher plus [+] Moins [-]Protective effect of Pleurotus cornucopiae mushroom extract on carbon tetrachloride-induced hepatotoxicity
2009
Bohi, K.M.E.(Zagazig Univ., Kaluobyia (Egypt)) | Hashimoto, Y. | Muzandu, K. | Ikenaka, Y. | Ibrahim , Z.S. | Kazusaka, A. | Fujita, S. | Ishizuka, M.
Pleurotus cornucopiae (PC) mushrooms are found in the field and commonly known in Japan as Tamogidake mushrooms. The present study investigated the protective effects of an aqueous extract of PC on carbon tetrachloride (CCl4)-induced hepatotoxicity and the possible mechanism involved in this protection including cytochrome P450 (CYP) 2E1. Wistar rats were pretreated with aqueous extracts of PC (0, 100, 200, and 400 mg/kg) orally for 8 days prior to the intraperitoneal administration of a single dose of CCl4 (0.5 ml/kg) or corn oil. Pretreatment with PC mushroom extract significantly prevented the increased serum enzyme activities of alanine and aspartate aminotransferases in a dose-dependent manner, and suppressed the expression of CYP2E1. PC mushroom extract also protected hepatocytes from the damage effects of CCl4 as remarked by histological and electromicroscopical findings. It was concluded that repeated daily doses of aqueous extracts of PC mushroom reduced the toxic effects exerted by CCl4 on the liver.
Afficher plus [+] Moins [-]Downregulation of male-specific cytochrome P450 by profenofos
2008
Moustafa, G.G.(Hokkaido Univ., Sapporo (Japan)) | Ibrahim, Z.S. | Ahmed, M.M. | Ghoneim, M.H. | Sakamoto, K.Q. | Ishizuka, M. | Fujita, S.
The health hazards of individual organophosphorus insecticides have been characterized by their acute toxicity, mainly by investigating their cholinesterase inhibition. However, the chronic effects of most of these toxicants on the drug-metabolizing enzymes have not been investigated. Profenofos (O-4-bromo-2-chlorophenyl O-ethyl S-propyl phosphorothioate) is an organophosphorus pesticide widely used in cotton cultivation. In the present study, we investigated the effect of profenofos on male-specific cytochrome P450 (CYP) enzymes in adult Wistar rats. We orally administered 17.8 mg/kg body weight, twice weekly for 65 days. Profenofos downregulated levels of hepatic and testicular CYP2C11 and CYP3A2 mRNA and protein expression. Testicular aromatase (CYP19A) mRNA was decreased in the profenofos-treated rats compared to controls. Overall, the present study suggests that profenofos acts as an endocrine disruptor of male-specific CYP enzymes and affects testosterone concentration, which implicates its deleterious effects on animal or human males chronically exposed to organophosphorus pesticide.
Afficher plus [+] Moins [-]Protection by Nigella sativa against carbon tetrachloride-induced downregulation of hepatic cytochrome p450 isozymes in rats
2008
Ibrahim, Z.S.(Hokkaido Univ., Sapporo (Japan)) | Ishizuka, M. | Soliman, M. | ElBohi, K. | Sobhy, W. | Muzandu, K. | Elkattawy, A.M. | Sakamoto, K.Q. | Fujita, S.
Nigella sativa (family Ranunculaceae ) is an annual plant that has been traditionally used on the Indian subcontinent and in Middle Eastern countries. In this study, we investigated the effect of N. sativa oil on the drug-metabolizing cytochrome P450 (CYP) enzymes and whether it has a protective effect against the acute hepatotoxicity of CCl4. Intraperitoneal injection of rats with CCl4 drastically decreased CYP2E1, CYP2B, CYP3A2, CYP2C11, and CYP1A2 mRNA and protein expressions. Oral administration of 1 ml/kg N. sativa oil every day for one week prior to CCl4 injection alleviated CCl4-induced suppression of CYP2B, CYP3A2, CYP2C11, and CYP1A2. Moreover, CCl4 increased iNOS and TNFalpha mRNA, while N. sativa oil administration for one week prior to CCl4 injection downregulated the CCl4-induced iNOS mRNA and up-regulated IL-10 mRNA. These results indicate that N. sativa oil administration has a protective effect against the CCl4-mediated suppression of hepatic CYPs and that this protective effect is partly due to the downregulation of NO production and up-regulation of the anti-inflamnatory IL-10.
Afficher plus [+] Moins [-]Effect of components of green tea extracts, caffeine and catechins on hepatic drug metabolizing enzyme activities and mutagenic transformation of carcinogens
2005
Nikaidou, S. (Hokkaido Univ., Sapporo (Japan)) | Ishizuka, M. | Maeda, Y. | Hara, Y. | Kazusaka, A. | Fujita, S.
Green tea contains catechins and caffeine as major constituents. Treatment of rats with green tea (2.5% w/v) significantly increased 7-ethoxycou-marin 0-deethylase (7-ECOD), caffeine N-1 demethylase (CN1D) and UDP-glucuronyltransferase (UGT) activities. Treatment with caffeine similarly activated CYP1A2 and related monooxygenases as well as UGT, while treatment with catechins induced UGT activity but not 7- ECOD or CN1D activity. Numbers of benzo[a]pyrene (BP) -induced revertant colonies in an Ames test (mutation assay) with S. typhimurium TA98 as the test strain were markedly larger when BP was preincubated with the liver S-9 (9000 x g supernatant of liver homogenate) from green tea-treated rats than when preincubated with that from control rats. In a modified Ames assay system in which UGT was activated by the addition of UDP-glucuronic acid to the preincubation mixture, numbers of revertant colonies in the assay using liver S-9 from green tea-treated rats decreased to a similar level to that in the assay using S-9 from controls. The acceleration of two enzymatic reactions may contribute to the rapid elimination of BP; the first step, the formation of a metabolic intermediate (which is mutagenic) by CYP1A2 and the second, the conjugation of active metabolic intermediates by UGT. We speculated that green tea can reduce the amount of time carcinogens reside in the body and the chance that body tis-sues will be exposed to active metabolites of carcinogens thorough rapid elimination due to the simultaneous induction of CYP1A2 and UGT activities.
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