The protective effects of melatonin, vitamin E, and selenium alone or in combination were tested against cadmium-induced oxidative damage in rat testes. A total of 60 male rats were equally divided into five study groups, one of which acted as control receiving subcutaneous injections of physiological saline. The remaining four groups were treated with subcutaneous injections of cadmium chloride at a dose of 1 mg/kg weight. The first study group received no treatment. The second group was treated with a combination of 60 mg/kg vitamin E and 1 mg/kg sodium selenite. Group 3 was treated with 10 mg/kg melatonin, and the fourth group received a combination of vitamin E, sodium selenite, and melatonin at the doses mentioned above. After 1 month, the animals were killed, and the testes were excised for histological inspection and determination of tissue malondialdehyde and the activity of superoxide dismutase. The animals receiving no treatment showed significantly higher malondialdehyde levels and reduced activity of the enzyme (p < 0.05). Treatment with antioxidants resulted in a significant reduction in malondialdehyde when compared to the nontreated animals (p < 0.05) and an increase in the superoxide dismutase activity that was almost the same as the controls. The combination of melatonin, vitamin E, and selenium appears to have the more profound effect against cadmium-induced testicular injury.

The aim of the current study was to investigate the protective effect of naringin on bleomycin-induced pulmonary fibrosis in rats. Twenty-four Wistar rats randomly divided into four groups (control, bleomycin alone, bleomycin + naringin 40, and bleomycin + naringin 80) were used. Rats were administered a single dose of bleomycin (5 mg/kg; via the tracheal cannula) alone or followed by either naringin 40 mg/kg (orally) or naringin 80 mg/kg (orally) or water (1 mL, orally) for 14 days. Rats and lung tissue were weighed to determine the lung index. TNF-α and IL-1β levels, hydroxyproline content, and malondialdehyde (MDA) levels were assayed. Glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities were determined. Tissue sections were stained with hematoxylin-eosin, Masson's trichrome, and 0.1% toluidine blue. TNF-α, IL-1β, and MDA levels and hydroxyproline content significantly increased (p < 0.01) and GPx and SOD activities significantly decreased in bleomycin group (p < 0.01). Naringin at a dose of 80 mg/kg body weight significantly decreased TNF-α and IL-1β activity, hydroxyproline content, and MDA level (p < 0.01) and increased GPx and SOD activities (p < 0.05). Histological evidence supported the results. These results show that naringin has the potential of reducing the toxic effects of bleomycin and may provide supportive therapy for conventional treatment methods for idiopathic pulmonary fibrosis.

The present study was carried out to evaluate the effect of exogenously administered metallothionein (MT) to rats exposed to high cadmium levels. A total of 72 rats were used in the study. The animals were divided into three groups: controls, Cd administered, and Cd+MT. Cadmium was administered by subcutaneous injection of cadmium(II) chloride at a dose of 3.5 mg/kg for 7 d. In addition to CdCl2, 30 micromol/kg MT was administered to the second group of rats (group II). Control rats received 0.5 mL physiologic serum via subcutaneous injection. Eight rats from each group were sacrificed on the 1st, 3rd, 5th, and 7th day after administration of the compounds. Liver, kidney, and blood samples were harvested. Levels of malondialdehyde (MDA), glutathione peroxidase (GSH-Px), serum ALT, AST, BUN, ALP, creatinine, and urea were measured. MDA levels in group I were observed to increase starting from d 1 compared to group II (p<0.05). Although MDA levels in group II were higher than controls (p<0.05), they were lower, especially in liver and blood, compared to group II. Erythrocyte GSH-Px activity levels were determined to decrease starting from d 1 in both groups (p<0.05). Decreases in GSH-Px activity levels in group II were less than group I. Serum creatinine levels in both groups were increased significantly compared to controls (p<0.05); the increase in group I was higher than group II. Serum ALT, AST, and ALP levels in group I increased to very high levels compared to controls, whereas increases in group II were at moderate levels (p<0.05). Although serum BUN levels were determined to be reduced, there was no significant change among the groups. Serum urea levels in both groups were higher than controls. Based on our results, it is possible to postulate that exogenous MT can act as antioxidant against Cd toxicity and lipid peroxidation.

Context: Morus nigra L. (Moraceae) has various uses in traditional medicine. However, the effect of M. nigra on cognitive impairment has not been investigated yet. Objective: The objective of this study is to determine the phenolic acid content and DNA damage protection potential of M. nigra leaf extract and to investigate the extract effect on cognitive impairment and oxidative stress in aging mice. Materials and methods: Phenolic acid content was determined by quantitative chromatographic analysis. DNA damage protection potential was evaluated on pBR322 plasmid DNA. Thirty-two Balb-C mice were randomly divided into four groups (control, D-galactose, D-galactose + M. nigra 50, and D-galactose + M. nigra 100). Mice were administered D-galactose (100 mg/kg, subcutaneous) and M. nigra (50 or 100 mg/kg, orally) daily for 8 weeks. Behavioral responses were evaluated with Morris water maze. Activities of antioxidant enzymes and levels of malondialdehyde (MDA) were assayed in serum, brain, and liver. Results: In extract, vanillic (632.093 mg/g) and chlorogenic acids (555.0 mg/g) were determined. The extract between 0.02 and 0.05 mg/mL effectively protected all DNA bands against the hazardous effect of UV and H 2 O 2 . Morus nigra significantly improved learning dysfunctions (p 50.01), increased memory retention (p50.01), reduced MDA levels (p50.05), and elevated SOD, GPx, and CAT activities (p50.05) compared with the D-galactose group. Discussion and conclusion: These results show that M. nigra has the potential in improving cognitive deficits in mice and that M. nigra may be useful to suppress aging, partially due to its scavenging activity of free radicals and high antioxidant capacity. ARTICLE HISTORY

No abstract

OBJECTIVE: The aims of this study were to investigate the protective effect of quercetin on changes in recognition memory as assessed by the novel object recognition (NOR) test, as well as on changes in the oxidative stress levels in the hippocampus and prefrontal cortex, produced in a model of memory impairment in schizophrenia induced by administration of a subanesthetic dose of ketamine. METHODS: A total of 40 Balb-C mice were randomly divided into five groups (Corn oil + Saline, Quercetin 50 + Saline, Corn oil + Ketamine, Quercetin 25 + Ketamine, Quercetin 50 + Ketamine). Corn oil and Quercetin (25 or 50 mg/kg/day) was given by orogastric gavage once daily for 21 days. Corn oil was chosen as the vehicle and administered at the same volume as quercetin. Ketamine was injected at a dose of 25 mg/kg intraperitoneally (i.p.) for a period of 7 days starting from the 15th day. Behavioural responses were evaluated with the NOR test. The activity levels of antioxidant enzymes and levels of malondialdehyde (MDA) were assayed in the prefrontal cortex and hippocampus. RESULTS: The time of exploration of the novel object was longer than T F (time to explore the familiar object) in the Corn oil + Saline and Quercetin 50 + Saline groups in NOR Test-1 (p < .05). The discrimination ratios of the Quercetin 50 + Ketamine and Corn oil + Ketamine groups were significantly lower than that of the Quercetin 50 + Saline group (p < .05). The discrimination ratios of the Quercetin 50 + Ketamine and Corn oil + Saline groups were significantly lower than that of the Quercetin 50 + Saline group (p < .05). The time of exploration of the novel object was longer than T F in the Corn oil + Saline and Quercetin 50 + Ketamine groups in NOR Test-2 (p < .05). The discrimination ratios of the Corn oil + Ketamine and Quercetin 25 + Ketamine groups were significantly lower than those of the Quercetin 50 + Ketamine group (p < .05). Quercetin at 50 mg/kg reduced the MDA levels and elevated the SOD and GPx activity compared to the Corn oil + Ketamine group. CONCLUSION: These results show that quercetin has the potential to improve cognitive deficits in mice and that quercetin may be useful for treating the symptoms of schizophrenia, partially due to its ability to scavenge free radicals and its high antioxidant capacity.

The present study was performed to determine the protective effects of melatonin alone and vitamin E with selenium combination against cadmium-induced oxidative damage in rat liver. A total of 60 male rats were equally divided into five groups, one of which acted as control receiving subcutaneous injections of physiological saline. The remaining four groups were treated with subcutaneous injections of cadmium chloride at a dose of 1 mg/kg weight. The first study group received no treatment. The second group was treated with a combination of 60 mg/kg vitamin E and 1 mg/kg sodium selenite. Group 3 was treated with 10 mg/kg melatonin, and the four group received a combination of vitamin E, sodium selenite, and melatonin at the doses mentioned above. After 1 month, the animals were killed, and liver and kidneys were excised for histopathological inspection and determination of tissue malondialdehyde and the activity of superoxide dismutase. The animals receiving no treatment showed significantly higher malondialdehyde levels and reduced activity of superoxide dismutase (p < 0.05). Treatment with antioxidants resulted in a significant reduction in malondialdehyde when compared to nontreated animals (p < 0.05) and increase in the enzyme activity that was almost the same as the controls. The pathological findings were also in parallel with the results of the biochemical analysis. In conclusion, all the agents tested had protective effects against cadmium-induced oxidative damage.

Ultrastructural changes in the kidneys of rats after acute cadmium exposure and the effects of exogenous metallothionein (MT) were studied by transmission electron microscopy. Thirty-six adult Wistar rats were divided into three groups. Cadmium chloride (CdCl2) (3.5 mg/kg/day) was injected subcutaneously in the first group. In the second group, 30 micromol/kg MT was administered in addition to CdCl2. Control rats received 0.5 ml subcutaneous saline solution. Four rats from each group were killed on days 1, 3, 5, and 7 after administration of the compounds. Kidney tissues were taken and fixed in 2.5% glutaraldehyde solution for electron microscopic observations. Tissue damage in kidney increased as time passed since the administration of CdCl2 in the first group. Degeneration in the proximal and distal tubules was observed. Increased apoptosis was seen in the proximal tubules epithelium, especially on day 7. Peritubular capillaries became dilated, there was degeneration of the endothelial cells, and the amount of intertubular collagen fibers was increased. On day 1, irregular microvilli in the proximal tubules, deepening of the basal striations, and myelin figures; on day 3, multiple vesicular mitochondria and regions of edema around tubules; on days 5 and 7, increased apoptotic cell in the proximal tubules and widened rough endoplasmic reticulum of the endothelial cells of glomerular capillaries were observed. We observed that the structural alterations that increased depending on the day of Cd administration decreased after exogenous MT administration, the dilation of the peritubular capillaries persisted, and there were degenerated proximal tubules. It was established that cadmium chloride was toxic for kidney cortex and caused structural damage. Exogenous MT partly prevents CdCl2-induced damage.