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» Veterinary Session
Veterinary sessionKarsai Szófia Ludmilla - year 4 SZIU Faculty of Veterinary Science, Department of Physiolgy and Biochemistry Supervisor: Anna Kulcsár Butyrate is a widely used feed additive due to its widespreading beneficial effects. It is applied worldwide as an alternative growth promoter in intensive poultry and pig nutrition. Based on its epigenetic effects butyrate can increase the production of certain enzymes at the level of transcription. It is already proved that dietary butyrate supplementation influenced the gene expression of hepatic cytochrome P450 (CYP450), which is one of the most important detoxification enzyme systems of the liver; however, it did not cause any significant changes in the activity of CYP450. Recent studies point to the importance of the CYP450 enzymes in the small intestine as well. The oral administration of butyrate could cause more direct effects on the intestinal mucosal cells than on hepatocytes. Hence we can hypothesize that butyrate may have bigger influence on the enteral CYP450 enzymes. In our study Ross 308 broiler chickens were fed with corn and wheat based diet, that can influence the endogenous butyrate production; without and with sodium butyrate or protected butyrate supplementation. After slaughtering, intestinal content samples were taken from the duodenum, ileum and caecum, and butyrate concentration of them was determined by gas chromatography. Samples were taken from the mucosa layer of the duodenum as well, and microsomal fractions were isolated by multiple-step differential centrifugation. The mean activity of CYP3A and CYP2C subfamilies, which are the main enzymes of biotransformation in the duodenum, was determined by aminopyrine N-demethylation assay. The results proved that the protected butyrate supplementation could increase the butyrate concentration in the duodenum and ileum, while in the caecum it was enhanced by the wheat based diet. Regarding the CYP450 enzyme activity in the intestine, our studies showed that in the corn fed groups sodium butyrate had no effect, but protected butyrate supplementation increased the activity of enzymes approximately fivefold compared to the control group. However, sodium butyrate and protected butyrate did not cause any changes as mixed into the wheat based diet, because wheat as carbohydrate source caused higher enzyme activity level without any supplementations. In conclusion we can state that protected butyrate supplementation causes more increased CYP450 enzyme activity in the duodenum than the sodium butyrate. This is because sodium butyrate is absorbed from the earlier section of the gut, while the protected butyrate passes it. Therefore, butyrate can be presented in the lumen of the duodenum with a relatively high concentration, so it is capable to affect the activity of enteral CYP450 enzymes. As a consequence, it can be suggested that protected butyrate may modify the metabolism of simultaneously applied drugs and xenobiotics. List of lectures |