No abstract

The aim of this study was to examine the effect of caffeic acid phenethyl ester (CAPE) on lipid peroxidation (LPO) and the activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in the liver of streptozotocin (STZ)-induced diabetic rats. Twenty-seven rats were randomly divided into three groups: group I, control non-diabetic rats (n = 9); group II, STZ-induced, untreated diabetic rats (n = 8); group III, STZ-induced, CAPE-treated diabetic rats (n = 10), which were intraperitoneally injected with CAPE (10 microM kg(-1) day(-1)) after 3 days followed by STZ treatment. The liver was excised after 8 weeks of CAPE treatment, the levels of malondialdehyde (MDA) and the activities of SOD, CAT, and GSH-Px in the hepatic tissues of all groups were analyzed. In the untreated diabetic rats, MDA markedly increased in the hepatic tissue compared with the control rats (p < 0.0001). However, MDA levels were reduced to the control level by CAPE. The activities of SOD, CAT, and GSH-Px in the untreated diabetic group were higher than that in the control group (p < 0.0001). The activities of SOD and GSH-Px in the CAPE-treated diabetic group were higher than that in the control group (respectively, p < 0.0001, p < 0.035). There were no significant differences in the activity of CAT between the rats of CAPE-treated diabetic and control groups. Rats in the CAPE-treated diabetic group had reduced activities of SOD and CAT in comparison with the rats of untreated diabetic group (p < 0.0001). There were no significant differences in the activity of GSH-Px between the rats of untreated diabetic and CAPE-treated groups. It is likely that STZ-induced diabetes caused liver damage. In addition, LPO may be one of the molecular mechanisms involved in STZ-induced diabetic damage. CAPE can reduce LPO caused by STZ-induced diabetes.

Diabetes mellitus increases oxidative stress and melatonin inhibits lipid peroxidation and might regulate the activities of antioxidant enzymes of diabetic rat testes.

In this study, the possible toxic effects of Alternariol Methyl Ether (AME) and Tenuazonic Acid (TeA) produced by Alternaria species on esophagu s of mice were investigated by using light and electron microscopy techniques. Mice were orally fed daily with AME or TeA for 10 months and at the end of this period, the effects of these chemicals on the esophagea l mucosa were determined. By light microscopi c examination, moderate and severe dysplasia characterized by loss of polarity, nuclear pleomorphism , and hyperchromasi a were observed in TeA-treated animals. Electron-microscopi c examination of TeA-treated mucosal epithelial cells revealed pyknosis in some nuclei, granulation and increase in chromatin mass, irregularities in the nuclear contours, vacuolization in nucleoplasms , and marked pleomorphism in the nuclei. In conclusion, our results suggested that TeA has higher toxicity as evidenced by dysplastic transformation.

Purpose To find the frequency and types of major chromosomal abnormalities with nonobstructive azoospermia and severe oligozoospermia to give appropriate genetic counseling before assisted reproduction techniques in Isparta (South of Turkey), and to investigate the general characteristics in this infertile male population. Methods and patients A total of 115 infertile males (92 were azoospermic, 23 severe oligospermic) were studied for the cytogenetic evaluation prior to use of assisted reproduction techniques. Also, 60 fertile males as a control group were studied. Karyotyping was performed on peripheral blood lymphocytes according to the standard methods. Levels of luteinising hormone, follicle-stimulating hormone (FSH), testosterone and prolactin were obtained and a testicular sonography examination was conducted. Results The total prevalence of chromosomal abnormalities was found to be 4.3% (5/115), including 4 patients with Klinefelter's Syndrome and 1 patient with gonadal dysygenesis (46XX). All of them were azoospermic males, corresponding to a frequency of 5.4% (5/92 patients). Oligozoospermic males and control males had no chromosomal abnormalities. There was a significant difference in serum FSH, LH, mean testicular volume and smoking when comparing patients (both azoospermic and oligozoospermic) and control groups (p<0.05). Also, there was a significant difference in serum FSH, LH and mean testicular volume when compared with azoospermic and oligozoospermic patients (p<0.05) Conclusions The occurrence of chromosomal abnormalities among infertile males strongly suggests the need for routine genetic testing and counseling prior to the employment of assisted reproduction techniques.

Epidemiological studies indicate that ochratoxin A (OTA) may be involved in the pathogenesis of different forms of human nephropathies. Melatonin (MEL) displays antioxidant and free radical scavenger properties. In the present study, the effect of MEL on the oxidative stress induced by OTA administration in rats was investigated. Three groups of eight rats each were used: control, OTA (289 micro g kg(-1) day(-1)) and OTA + MEL (OTA, 289 micro g kg(-1) day(-1); MEL, 10 mg kg(-1) day(-1)), with treatment at two different time periods during the same day. After 4 weeks of treatment, the levels of lipid peroxidation (LPO) and the activities of catalase, superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) were measured in homogenates of kidney. In OTA-treated rats, the levels of LPO and the activities of GSHPx and SOD were significantly decreased compared with controls. In OTA + MEL-treated rats, SOD, GSHPx and catalase activities and LPO levels were not changed significantly in comparison with controls.

In this study, we aimed to investigate the possible protective effects of caffeic acid phenethyl ester (CAPE) on lipid peroxidation (LPO) and the activities of antioxidant enzymes in the liver of rats exposed to the 900 MHz electromagnetic field (EMF). EMF of cellular phones may affect biological systems by increasing free radical, which appear mainly to enhance LPO, and by changing the antioxidative activities of liver, thus leading to oxidative damage. CAPE, an active component of propolis extract, exhibits antioxidant properties and several studies suggest that supplementation with antioxidant can influence EMF exposure induced hepatotoxicity. Thirty male Sprague-Dawley rats were divided into three groups: control (n = 10), 900 MHz EMF (n = 10) and 900 MHz EMF + CAPE (n = 10). CAPE was injected intraperitoneally for 30 days before exposure to EMF. Liver tissue was removed to study the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), xanthine oxidase (XO) and the levels of LPO. The activities of XO, CAT and level of LPO increased in the 900 MHz electromagnetic field (EMF) group compared with the control group, although XO, CAT activities and LPO levels were decreased by 900 MHz EMF + CAPE administration. The activities of SOD and GSH-Px decreased in the 900 MHz EMF group compared with the control group, although their levels were increased by EMF + CAPE administration. It can be concluded that CAPE may prevent the 900 MHz EMF-induced oxidative changes in liver by strengthening the antioxidant defense system by reducing reactive oxygen species and increasing antioxidant enzyme activities.

Various studies indicate that the mycotoxin ochratoxin A (OTA) is a carcinogenic, genotoxic, teratogenic, immunotoxic, and nephrotoxic agent. In the present study, the activities of some enzymes in the serum and liver of rats with ochratoxicosis and the effects of melatonin on these enzymes were investigated. Rats were divided into three equal groups, each consisting of eight rats; control, OTA (289 microg/kg per day) and OTA + melatonin groups for this study. In the OTA treated group, the level of lipid peroxidation (LPO) and the activities of glutathione peroxidase (GSH-Px) were increased in the liver and serum in comparison with the control group. The activities of catalase (CAT) and superoxide dismutase (SOD) were significantly changed in the serum when compared with controls. Our results showed structural tissue damage in the liver in OTA-treated rats. Melatonin decreased the OTA-induced damage to support the antioxidant defense system and/or with free radical scavenger action.