Investigation of the Effect of Milrinone on Renal Damage in an Experimental Non-Heart Beating Donor Model.

PURPOSE: In our study, it was aimed to investigate the preventive effect of milrinone on renal damage in experimental controlled non-heart-beating donors (NHBDs) model. MATERIALS AND METHODS: Sixteen rats randomly divided into 2 groups, 8 rats in each were used. Group 1 was control, group 2 was milrinone group. Group 1 rats received 1.25 ml 0.09% NaCl intraperitoneally equivalent to the milrinone diluted volume. Group 2 rats were administered intraperitoneally with 0.5 mg/kg of milrinone 2 hours before cardiac arrest. After the cardiac arrest, left nephrectomy was applied to the rats. Malondialdehyde, superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx) activities, Caspase-3 (apoptotic index) and histopathological evaluation were performed in the tissues. RESULTS: In the milrinone group, the total injury score was significantly lower relative to the control group (p = 0.001). Caspase-3 staining was moderately strong in the control group but weaker in the milrinone group. Apoptotic index was significantly lower in the milrinone group compared to the control group (p = 0.001). In comparison between groups, SOD and GPx in the milrinone group was significantly higher than the control group (p = 0.008, p = 0.006). CONCLUSIONS: Milrinone has been shown to be effective in the prevention of tissue damage due to oxidative stress and inflammatory process in the renal of warm ischemia in the experimental NHBDs model and in protecting the renal. Milrinone increases antioxidant activity while reducing apoptosis. Systemic administration of milrinone prior to cardiac arrest may be beneficial. Administration of milrinone to the recipient in the perioperative period may contribute to donor function.

Gastric tissue oxidative changes in portal hypertension and cirrhosis.

Gastric mucosal lesions are very common in portal hypertension and cirrhosis. The aim of this study was to assess for oxidative gastric tissue damage in cirrhosis and evaluate relations with portal hypertension and cirrhosis parameters. The study included 30 patients with cirrhosis and 30 controls. Each patient's history, physical examination, and laboratory findings were recorded, and multiple biopsies of the gastric antrum were obtained at endoscopy. A set of antral biopsies was also collected from each control subject. Each tissue specimen was analyzed for levels of glutathione peroxidase (GPX), superoxide dismutase (SOD), and catalase (CAT) activity and level of malondialdehyde (MDA). Patients' gastric GPX, SOD, and CAT levels were significantly lower, and MDA levels were higher, than in the control group. The GPX activity level in the specimens was moderately negatively correlated with portal vein diameter (P<0.05, r=-0.45) and spleen length (P<0.05, r=-0.45). In this study gastric tissue oxidative markers showed that antral oxidative factors worsen in cirrhosis. Oxidative stress may not be a clinical condition but it obviously shows gastric tissue damage and may explain many patients' gastric lesions and hemorrhage.

The evaluation of the oxidant injury as a function of time following brain irradiation in a rat model.

This study presents the evaluation of the oxidant injury as a function of time following brain irradiation in a rat model. Thirty-five Wistar rats were divided into seven groups. The rats in Group 1 through Group 6 underwent irradiation, whereas the rats in Group 7 underwent sham irradiation. The rats in Group 1 through Group 6 underwent euthanasia at 1 through 48 h following irradiation, whereas the rats in Group 7 underwent euthanasia immediately following sham irradiation. At the time of euthanasia, the brain tissue was dissected for evaluation of the malondialdehyde (MDA) level and the superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSHPX) activities. The mean MDA levels were increased and the mean SOD, CAT and GSHPX activities were decreased at all of the time points for evaluation for the rats that underwent irradiation as compared to the rats that underwent sham irradiation, substantial for Group 1 and gradually leveling out through Group 6. This study confirms that the oxidant injury is evaluated at its best through the first several hours following brain irradiation.

Lipid peroxidation and antioxidant status in stomach cancer.

BACKGROUND: Considerable evidences have linked oxidative damage and cancer. In this article, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) activities, and malondialdehyde (MDA) and nitric oxide metabolites' levels (NO(x)) were investigated in patients with stomach cancer. METHODS: All measurments were done by spectrophotometric techniques. RESULTS: We observed a significant decrease in the activities of SOD and CAT in tumour tissues when compared with control tissues. The different of GSHPx activities and NO metabolite' levels were not statistically significant. MDA levels were significantly increased. CONCLUSIONS: We conclude that increased MDA levels and decreased antioxidant enzyme activities can be valuable parameters in assessing the possible risk of cancer.

Potent therapeutic effect of melatonin on aging skin in pinealectomized rats.

It is generally agreed that one of the major contributors to skin aging is reactive oxygen species. As organisms reach advanced age, free radical generation increases and the activity of tissue antioxidant enzyme system decreases. Melatonin is an antioxidant and free radical scavenger. The present study was first aimed to determine the morphometric and biochemical changes caused by long-term pinealectomy in order to investigate the role of melatonin as skin architecture. Secondly, the effect of exogenous melatonin administration on these changes was determined. Rats were pinealectomized or sham operated (control) for 6 months. Half of the pinealectomized rats were treated with 4 mg/kg melatonin during the last month of the experiment. Pinealectomy resulted in important morphometric and biochemical changes in the back, abdominal and thoracic skin. The thickness of epidermis and dermis and the number of dermal papillae and hair follicles were reduced. Melatonin administration to pinealectomized rats significantly improved these alterations in all body areas (P < 0.005). On the contrary, in pinealectomized rats the levels of antioxidant enzymes, catalase and glutathione peroxidase were decreased. Melatonin restored the levels of these enzymes. The pinealectomy-induced increases in lipid peroxidation in the abdominal and thoracic skin were significantly reduced by melatonin treatment (P < 0.005 and 0.01 respectively). These results suggest that melatonin is highly efficient anti-aging factor and, as melatonin levels decrease with age, melatonin treatment may reduce age-related skin changes.