Protective effect of apricot (Prunus armeniaca L.) on hepatic steatosis and damage induced by carbon tetrachloride in Wistar rats.

The present study was planned to investigate the protective effect of 10 % and 20 % apricot-containing feed on carbon tetrachloride (CCl4)-induced hepatic steatosis and damage. Adult male Wistar rats (n 42) were divided into six groups of seven each, as follows: control group; CCl4 group; CCl4+10 % apricot group; CCl4+20 % apricot group; 10 % apricot group; 20 % apricot group. All apricot groups were fed with 10 % or 20 % apricot-containing feed for 5 months. CCl4 injections were applied to the CCl4 groups at the dose of 1 mg/kg for 3 d at the end of 5 months. In the CCl4 group, vacuolated hepatocytes and hepatic necrosis were seen, especially in the centrilobular area. Hepatocytes showed an oedematous cytoplasmic matrix, large lipid globules and degenerated organelles. The area of liver injury was found significantly decreased with apricot feeding. Malondialdehyde and total glutathione levels and catalase, superoxide dismutase and glutathione peroxidase activities were significantly changed in the CCl4 group and indicated increased oxidative stress. Apricot feeding decreased this oxidative stress and ameliorated histological damage. We concluded that apricot feeding had beneficial effects on CCl4-induced liver steatosis and damage probably due to its antioxidant nutrient (beta-carotene and vitamin) contents and high radical-scavenging capacity. Dietary intake of apricot can reduce the risk of liver steatosis and damage caused by free radicals.

Comparison of plasma malondialdehyde, glutathione, glutathione peroxidase, hydroxyproline and selenium levels in patients with vitiligo and healthy controls.

BACKGROUND: The etiology and pathophysiologic mechanism of vitiligo are still unclear. The relationship between increased oxidative stress due to the accumulation of radicals and reactive oxygen species and the associated changes in blood and epidermal component of vitiliginous skin have been reported many times. We investigated the possible changes of plasma malondialdehyde, glutathione, selenium, hydroxyproline and glutathione peroxidase activity levels in patients with vitiligo in order to evaluate the relationship between oxidative stress and etiopathogenesis of vitiligo. MATERIALS AND METHODS: Plasma malondialdehyde, glutathione, hydroxyproline and glutathione peroxidase activity levels were measured by spectrophotometric methods, and HPLC was used for measurement of selenium concentrations. RESULTS: Our results showed increased malondialdehyde, hydroxyproline and glutathione peroxidase activity levels in plasma of vitiligo group (P < 0.05). CONCLUSION: Support of antioxidant system via nonenzymatic antioxidant compounds and antioxidant enzymes may be useful to prevent of melanocyte degeneration which occur due to oxidative damage in vitiligo.

The effect of melatonin on 7,12-dimethyl-benz[a]anthracene injury in comparison with vitamin E + selenium in mouse kidneys.

The aims of this study were to observe the changes in antioxidative defense enzymes and renal morphology after 7,12-dimethyl-benz[a]anthracene (7,12-DMBA) administration in mice and to investigate the possible protective effects of melatonin against 7,12-DMBA-induced renal damage in comparison with vitamin E + selenium (vit E + Se). Forty female mice were divided into four groups: control, DMBA, DMBA + vit E + Se and DMBA + melatonin. In the DMBA group, mice were given injections of 7,12-DMBA (20 mg/kg). DMBA + vit E + Se group mice received injections of 7,12-DMBA + vit E + Se (20 mg/kg + 90 mg/kg + 1.8 microg/kg). In the melatonin group, mice were given injections of 7,12-DMBA + melatonin (20 mg/kg + 4.2 mg/kg). The experiment lasted for 21 days. Mice were killed and the kidneys were taken for enzyme analyses and histologic examination. Catalase (CAT) and glutathione peroxidase (GSH-Px) activities were found significantly decreased in the DMBA group and in the DMBA + vit E + Se group when compared with the control group (P < 0.05), whereas CAT and GSH-Px activities were found significantly elevated in the DMBA + melatonin group when compared with the control (P < 0.05) and the DMBA group (P < 0.01). Exposure to DMBA resulted in tubular alterations in renal cortex. Morphometric analysis revealed proximal and distal tubular damage (P < 0.05). These alterations were found to be prevented by melatonin but not with vit E + Se administration. These results reveal that melatonin stimulates CAT and GSH-Px activities and prevents renal injury better than vit E + Se combination in mice kidneys.

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.

Alterations in antioxidant enzyme activities in cerebrospinal fluid related with severity of hypoxic ischemic encephalopathy in newborns.

BACKGROUND: The antioxidant status of the tissue affected by ischemia-reperfusion is of great importance for the primary endogenous defense against the free-radical-induced injury. OBJECTIVE: In this study, we aimed to evaluate the relationship between the activities of antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT)] in cerebrospinal fluid (CSF) and severity of hypoxic-ischemic encephalopathy (HIE) in newborns. METHODS: Thirty full-term asphyxiated infants (gestational age >37 weeks) and 11 full-term infants (none of whom showed any signs of asphyxia) were included in this study. Activities of SOD, GPX, and CAT in CSF were measured within the first 72 h of life in infants with HIE and controls. RESULTS: Activity of SOD in CSF was significantly higher in infants with HIE compared with controls (p<0.05). GPX and CAT activities were higher in infants with HIE than they were in controls; however, the differences were not statistically significant (p > 0.05). The activities of GPX and CAT were significantly increased in severe HIE as compared with mild HIE and controls (p < 0.05). CONCLUSION: Both the duration of the hypoxic-ischemic insult and the severity of HIE modulate elevations of enzymatic activity as an adaptive response to excessive free radical production in CSF in newborn infants with HIE. The activities of antioxidant enzyme alterations in CSF correspond highly to the severity of HIE, and these patterns may be useful for diagnostic and prognostic purposes.

Carbon tetrachloride-induced nephrotoxicity and protective effect of betaine in Sprague-Dawley rats.

OBJECTIVES: To observe the changes in the antioxidative defense enzymes and to detect the alterations of renal microscopy after carbon tetrachloride (CCl4) administration in rats and to investigate the possible protective effects of betaine against CCl4-induced renal damage. METHODS: Thirty-two adult Sprague-Dawley rats were divided into four groups as follows: control group, betaine group, CCl4 group, and CCl4 + betaine group. CCl4 was given subcutaneously at 1 mL/kg. In the CCl4 + betaine group, rats were pretreated with betaine, then exposed to CCl4 at the same dose. Betaine group rats received concentrated betaine solution. The rats were killed and the kidneys taken for enzyme analyses and histologic examination. Glutathione peroxidase, superoxide dismutase, and catalase activities were measured in right kidney homogenates. Left kidneys were processed for light microscopic evaluation. RESULTS: In the CCl4-treated group, significant increases in kidney superoxide dismutase and catalase activities and significant decrease in glutathione peroxidase activity were observed (P <0.01). These changes were found to be normalized in the CCl4 + betaine group. Betaine did not change the enzyme activities. Exposure to CCl4 resulted in glomerular and tubular alterations in the renal cortex. These alterations were found to be prevented by betaine pretreatment. CONCLUSIONS: These results indicate that exposure to CCl4 leads to renal damage in rats and betaine exerts an improvement on nephrotoxic effects of CCl4.

Investigation of the relationship between nitric oxide metabolites' levels and adenosine deaminase activity in 7,12-dimethylbenz[a]anthracene induced mouse liver.

7,12-Dimethylbenz[a]anthracene (7,12-DMBA) is a member of the polycyclic aromatic hydrocarbons with a severe carcinogenic effect. In this study, nitrate levels and ADA (Adenosine deaminase) activity in the liver homogenates of mice were measured and the effect of free radicals induced by 7,12-DMBA on inducible nitric oxide synthase (iNOS) and ADA activity were investigated. Antioxidant effects of melatonin were also compared. Three groups of mice were included in the study. The first served as control, the second was treated only with 7,12-DMBA and the third was treated with 7,12-DMBA + melatonin. Spectrophotometric methods were used at all measurements. Data were analyzed using Kruskal-Wallis Variance Analysis Test and Mann-Whitney U Test that were applied to the groups. The nitrate concentrations of mouse liver were as follows: 4.98 +/- 0.63 micro mol/L in the control group (n = 10), 8.23 +/- 1.58 micro mol/L (higher than control group, p < 0.05) in the 7,12-DMBA-treated group (n = 10), and 6.43 +/- 0.57 micro mol/L (lower than 7,12-DMBA-treated group, p < 0.05) in the 7,12-DMBA + melatonin-treated group (n = 10). Liver ADA activities were measured to be 4.14 +/- 0.674 U/L in the control group, 6.25 +/- 1.261 U/L (higher than control group, p < 0.05) in the 7,12-DMBA-treated group, and 4.93 +/- 0.916 U/L (lower than 7,12-DMBA-treated group, p < 0.05) in the 7,12-DMBA+melatonin-treated group. Differences between free nitrite levels were no significantly. Results demonstrated that nitrate levels and ADA activities were increased by means of free radicals induced by 7,12-DMBA. Melatonin inhibited the 7,12-DMBA induced increase that was observed in the activities of ADA enzyme and nitrate levels. It is concluded that determination of ADA activity and nitrate levels can be useful in the assessment of liver damage caused by toxic chemicals.