Metin Ogun

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.

Protective effect of omega-3 fatty acid against mercury chloride intoxication in mice.

The aim of this study was to investigate the protective effect of omega-3 fatty acid in HgCI2 toxicity in mice. Levels of malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide (NO) and total sialic acid (TSA), and histopathological changes in selected organs were evaluated. Twenty-eight mice were equally divided into 4 groups, namely Groups I-IV. Group I animals received intraperitoneal (ip) injection of physiological saline solution; Group II animals received ip injection of 0.4mg/kg/day HgCI2; Group III animals received ip injection of 0.4mg/kg/day HgCI2 in addition to subcutaneous (sc) injection of 0.5g/kg/day omega-3 fatty acid; and Group IV animals received sc injection of 0.5g/kg/day omega-3 fatty acid. All treatments lasted 7 days. The levels of MDA, NO and TSA were significantly higher in Group II and lower in Groups III and IV as compared to the Group I. GSH level was the highest in Group IV. In histopathology, severe degeneration in liver and kidney was observed in Group II animals. These degrading changes were seen to be reduced greatly in Group III animals. The results suggested that omega-3 fatty acid might attenuate HgCI2-induced toxicity by improving antioxidant status and acute phase response in mice.

Biochemistry of Reactive Oxygen and Nitrogen Species

Reactive species or free radicals include reactive oxygen and nitrogen species that are called reactive oxygen nitrogen species. Reactive oxygen species are formed as a natural by-product of the normal metabolism of oxygen and have significant roles in cell signaling and homeostasis. The reactive oxygen species are generated as a byproduct of biochemical reactions, in mitochondria, peroxisomes, cytochrome P450, and other cellular components. When oxygen homeostasis is not maintained, oxidative stress is increased in the cellular environment. Superoxide, hydrogen peroxide and hydroxyl radicals are normal metabolic by-products which are generated continuously by the mitochondria in growing cells. Microsomal cyto‐ chrome P450 enzymes, flavoprotein oxidases and peroxisomal enzymes are other significant intracellular sources of reactive oxygen species.

Effects of Intrathecal Administration of Ketamine HCl in Young Calves: A Clinical Trial

Abstract The purpose of the study was to investigate the clinical, biochemical, and cardiovascular effects of intrathecal (IT) administration of ketamine HCl in calves. The study was performed on seven Simmental and three Montofon calves, 1.70 ± 1.16 weeks old, weighing approximately 37 kg, undergoing surgical procedures including femur fracture repair (one case), atresia anus (five cases), prolapsed rectum (one case), suturing on rear limbs (two cases), and urethrostomy (one case). After administering IT ketamine HCl at a dose of 3 mg/kg to all calves, the level and depth of the anaesthesia was checked with a pin-prick test. Each animal was monitored by recording heart rate, arterial blood pressure, respiratory rates, and rectal temperature. Furthermore, certain biochemical parameters, blood gases, oxygen-total haemoglobin, and electrolyte levels were measured. All data were statistically evaluated using Minitab 16 software. Anaesthesia occurred in all calves at an average of 5.00 ± 1.41 min (range: 3-7) and continued for an average of 61.4 ± 40 min (range: 55-70). Sufficient anaesthesia was achieved in all animals for the required operations, and no complications occurred with regard to clinical and haemodynamic measurements. We concluded that in calves, which are not deemed suitable for administration of local anaesthetic via IT due to certain side effects, sufficient anaesthesia can be provided with ketamine by the same method for operations performed in the perineal area and hind extremities, and that this could be a good alternative for anaesthesia under field conditions.