Tissue specific effects of feeds supplemented with grape pomace or olive oil mill wastewater on detoxification enzymes in sheep

The aim of the present study was to investigate the effects of livestock feed supplemented with grape pomace (GP) or olive oil mill wastewater (OMW) byproducts on the enzymatic activity and protein expression of antioxidants enzymes, in liver and spleen tissue of sheep. Thus, 36 male sheep of Chios breed were divided into 3 homogeneous groups, control group (n = 12), GP group (n = 12) and OMW group (n = 12), receiving standard or experimental feed. Liver and spleen tissues were collected at 42 and 70 days post-birth. The enzymatic activity of superoxide dismutase (SOD) and glutathione-s-transferase (GST) and also the protein expression of γ-synthase glutamyl custeine (γ-GCS) were determined in these tissues. The results showed GP group exhibited increased enzymatic activity of GST and protein expression of γ-GCS in liver compared to control group. In GP group's spleen, GST activity was increased compared to control but γ-GCS expression was not affected. In OMW group's liver, GST activity was increased and γ-GCS expression was reduced compared to control. In OMW group's spleen, GST activity was increased but GCS expression was not affected. SOD activity was not affected in both tissues either in GP or OMW group.