0000000000071446
AUTHOR
Michel Petit
Changes in terpene content in milk from pasture-fed cows
International audience
Response of genetically obese Zucker rats to ciprofibrate, a hypolipidemic agent, with peroxisome proliferation activity as compared to Zucker lean and Sprague-Dawley rats.
Genetically obese Zucker (fa/fa) rats were used as an experimental model to study the effects of hypolipidemic agents on peroxisome proliferation; comparison was made with Zucker lean phenotype (Fa/-) and Sprague-Dawley strain/phenotype. The pharmacokinetics of a single administration of ciprofibrate (1 or 3 mg/kg), appeared to be similar in all strains/phenotypes. After a 2-week oral administration at the same dosages, there were dosage-related increases in hepatocellular peroxisomal yield and in the hepatic enzymes' cyanide-insensitive acyl-CoA oxidase and catalase. The peroxisomal yield was less increased in Zucker than in Sprague-Dawley rats, while the enzyme activities were similarly i…
Difference between Guinea Pig and Rat in the Liver Peroxisomal Response to Equivalent Plasmatic Level of Ciprofibrate
Abstract Guinea pig was previously classified as a species nonresponsive to peroxisome proliferators. However, none of the previous reports was based on pharmacokinetic data. Here, after a comparative pharmacokinetic study between guinea pig and rat, we evaluate the guinea pig liver peroxisomal response to ciprofibrate, a hypolipemic agent and a potent peroxisome proliferator in rat. (1) Pharmacokinetic results show that plasmatic concentrations of ciprofibrate are equivalent in guinea pig and rat when guinea pigs are treated with ciprofibrate at 30 mg/kg twice a day and rats are treated at 3 mg/kg once a day. (2) The treatment of guinea pigs at 30 mg/kg twice a day for 2 weeks leads to a s…
Peroxisomes and Hepatotoxicity
Peroxisomes are ubiquitous organelles of eukaryotic cells and are present in significant amounts in hepatic liver cells. Peroxisomal enzymes contribute to several metabolic pathways including fatty acid, purine and amino acid catabolism or bile acid synthesis. The peroxisomal oxidative reactions produce hydrogen peroxide, mostly degraded by catalase which prevents oxidative stress. Moreover, peroxisomes are involved in arylderivative drug detoxification through its epoxide hydrolase activity.