Abdulsamed Kükürt

Oleuropein ameliorates arsenic induced oxidative stress in mice.

The objective of this study is to investigate the potential preventive effect of oleuropein in an experimental arsenic toxicity in mice. For this purpose, mice were exposed to 5mg/kg/day sodium arsenite (NaAsO2) in drinking water and treated with 30mg/kg/day oleuropein for 15 days. At the end of the experiment, animals were sacrificed and selected organs were processed for biochemical and histopahtological investigations. Blood, liver, kidney and brain malondialdehyde (MDA) and nitric oxide (NO) levels were determined by colorimetric methods. Protein carbonyl content is measured by a commercial kit. Liver morphology and immunoreactivity for inducible NOS (iNOS) and endothelial NOS (eNOS) was evaluated microscopically. Level of NO was determined to decrease in blood and tissues whereas MDA increased in arsenic given mice. Tissue protein carbonyl content also increased in this group. Immunoreactivity for iNOS and eNOS was noted to increase with arsenic treatment. Oleuropein treatment had significant effects in normalizing the MDA and NO levels as well as protein carbonyl content. Immunohistochemical staining also showed reduction of the expression of iNOS and eNOS in liver. The results indicate that oleuropein ameliorates oxidative tissue damage by scavenging free radicals.

Investigation of Serum Oxidative Stress Index and Paraoxonase Activity Levels in Colostrum Period of Dairy Cows

In this study, the investigation of serum oxidative stress index (OSI), paraoxonase 1 (PON1) activity, total antioxidant (TAS) and oxidant status (TOS) levels in colostrum period of dairy cows was aimed. It was used sixteen Simmental cows for blood samples as follows: within 0, 1, 2, 3 and 4 days postpartum (group I, II, III, IV and V, respectively). Serum TAS, TOS and PON1 activity levels were determined by spectrophotometric methods. The results showed that oxidative stress in group IV was higher than group I and II. PON1 activity in group V was significantly higher than other groups. It was concluded that serum oxidative stress and PON1 activity levels in colostric period of dairy cows changed daily.