The effects of walnut supplementation on hippocampal NMDA receptor subunits NR2A and NR2B of rats.

OBJECTIVES: Walnuts contain numerous selected dietary factors that have an impact on brain functions, especially learning and memory formation in the hippocampus. Hippocampal N-methyl d-aspartate receptors (NMDARs) are involved in the formation of cognitive functions. In this study, we aimed to investigate the molecular effects of walnut supplementation on the hippocampal expressions of NMDARs involved in cognitive functions and lipid peroxidation levels in rats. METHODS: The male Sprague-Dawley rats (6 months old, n = 24) were fed with a walnut-supplemented diet (6% walnut diet, n = 12) and a control diet (rat food, n = 12) as ad libitum for 8 weeks. At the end of this period, NMDAR subunits NR2A and NR2B in the hippocampi were assayed by western blotting. Lipid peroxidation levels were measured using the thiobarbituric acid. RESULTS: The expression of NR2A and NR2B was elevated in the walnut-supplemented rats compared with the control group (P < 0.05). In addition, the levels of lipid peroxidation in the walnut-supplemented group were significantly decreased compared with the control group. DISCUSSION: We suggested that walnut supplementation may have protective effects against the decline of cognitive functions by regulating NMDAR and lipid peroxidation levels in the hippocampus. The study provides evidence that selected dietary factors (polyunsaturated fatty acids, melatonin, vitamin E, and flavonoids) within walnut may help to trigger hippocampal neuronal signal transduction for the formation of learning and memory.

The protective effect of Capparis ovata on 6-mercaptopurine-induced hepatotoxicity and oxidative stress in rats.

Capparis ovata is a member of Capparidacaeae family has been used in phytomedicine with a lot of positive effects such as an antioxidative, antihyperlipidemic, anti-inflammatory, and antihepatotoxic agent. The aim of this study was to research the protective effect of C. ovata on 6-mercaptopurine (6-MP) induced to hepatotoxicity and oxidative stress in rats. The rats were divided into 4 groups: control, 6-MP, C. ovataovate, and 6-MP + C. ovata. A complete blood count was performed, liver function test and antioxidant enzymes levels such as superoxide dismutase, glutathione peroxidase, catalase, and malondialdehyde were measured in blood before and after a 14-day test period. White blood cell and platelet counts were lower in the 6-MP group than other 3 groups (P < 0.005). Hepatic transaminase levels were higher in 6-MP group than the 3 groups (P < 0.05). Superoxide dismutase, glutathione peroxidase, and CAT levels were lower and malondialdehyde was higher in blood samples in 6-MP group than other 3 groups (P < 0.005). In conclusion, our tests were showed that C. ovata may be useful in patients receiving 6-MP therapy to prevent hepatotoxicity and in order to maintain uninterrupted therapy possibly reducing the risk of relapse. Although additional studies ensure that Capparis does not affect 6-MP antileukemic activity. We believe these results are important contribution to the literature.

The role of carnitine in preventing renal damage developed as a result of infrarenal aortic ischemia-reperfusion.

BACKGROUND: This study was designed to use carnitine for preventing deposition of end products of lipid peroxidation in rat models in the prevention of ischemia-reperfusion (IR) damage frequently seen following operations of infrarenal abdominal aorta (AA). METHODS: Forty male rats of Sprague-Dawley type were evenly (n = 8) randomized to five groups: sham laparotomy (SHAM), carnitine control (CC), aortic IR (AIR), AIR + low-dose carnitine (AIR+LDC), and AIR + high-dose carnitine (AIR+HDC). RESULTS: Compared to other groups, serum creatinine levels of AIR group were significantly higher. Also tissue malondialdehyde (MDA) levels of AIR group were significantly higher compared to SHAM, CC, and AIR+HDC groups. In histopathological examination, although tubular necrosis atrophy and tubular degeneration observed in AIR group showed regression with low-dose carnitine, tubular necrosis atrophy, tubular degeneration, glomerular damage, and vascular congestion thrombosis decreased with high-dose carnitine. Total score of histological damage was significantly higher in AIR, AIR+LDC, and AIR+HDC groups compared to SHAM and CC groups. Moreover, total score of histological damage was significantly lower in AIR+HDC group than AIR+LDC group. CONCLUSIONS: In this study, we showed carnitine can partially prevent renal damage in infrarenal AIR models of rats. This result may open new prospects to us in the prevention of renal IR damage during surgery of aorta.

Ghrelin and adiponectin levels in colostrum, cord blood and maternal serum.

BACKGROUND: Ghrelin and adiponectin, which are considered to take part in the regulation of energy metabolism, have been found in breast milk and cord blood. The aims of this study were to determine ghrelin and adiponectin levels in colostrum, cord blood and maternal serum and to investigate the correlations between colostrum and cord blood levels of these peptides and the anthropometry of newborn infants and their mothers. METHODS: Total ghrelin (TGHR), free ghrelin (FGHR) and adiponectin levels were studied in colostrum and the serum samples of 25 healthy lactating women and the cord blood of their healthy full-term infants. RESULTS: No significant differences could be found among TGHR and adiponectin levels in colostrum, cord blood and maternal serum. The median FGHR level in colostrum was significantly higher than that of maternal serum and cord blood. The colostrum TGHR was negatively correlated with body mass index (BMI) and weight of the infants at birth. TGHR and FGHR levels in colostrum were found to be positively correlated with those of maternal TGHR and FGHR concentrations, respectively. Adiponectin levels in colostrum were not correlated with BMI or birthweight of the infants or BMI of the mothers. CONCLUSION: These findings suggest that the source of ghrelin in breast milk is probably both breast tissue itself and the serum of the mother. Ghrelin in colostrum seems to be related to the anthropometry of infants even at birth, unlike adiponectin.

Pentoxifylline, a methyl xanthine derivative, reduces peritoneal adhesions and increases peritoneal fibrinolysis in rats.

Peritoneum has an intrinsic fibrinolytic activity that breaks the peritoneal adhesions. Peritoneal injuries with ischemia interfere this fibrinolytic activity and cause adhesions. Pentoxifylline, a methyl xanthine derivative, improves blood flow by decreasing its viscosity and also increases fibrinolytic activity in plasma. We hypothesized that pentoxifylline would increase peritoneal fibrinolysis and ameliorate adhesions. A rat model of peritoneal adhesion (cecal abrasion with gauze, n = 15 for each group) was used to test this hypothesis and cardinal parameters of peritoneal fibrinolysis were measured in peritoneal samples. No medication was given in control animals, while pentoxifylline was administered intraperitonealy (IP) (25 mg/kg, before abdominal closure to whole abdomen) or intravenously (IV) (25 mg/kg, for 9 days after operation) in the experimental groups. At postoperative day 10, peritoneal biopsies were obtained and adhesions were graded qualitatively. Activities and concentrations of tissue plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1), tPA/PAI-1 complex and hydroxyproline contents were determined. Total adhesion scores were decreased in both treated groups. Mean levels of tPA concentration and tPA activity were increased in the treated groups compared to controls (p < 0.001 and p = 0.001, respectively). The tPA/PAI-1 complex levels were similar among the three groups. PAI-1 levels were lower in animals receiving IP pentoxifylline compared to control animals and those treated with IV pentoxifylline (p = 0.048, p = 0.015, respectively). Peritoneal hydroxyproline levels were similar among the three groups. Our results suggest that pentoxifylline administration either through IV or IP may reduce peritoneal adhesion formation probably by altering peritoneal fibrinolytic activity.

Effects of dietary long chain PUFAs on hippocampal lipid peroxidation and NMDA receptor subunits A and B concentration in streptozotocin-diabetic rats.

This study examined the effects of streptozotocin (STZ)-diabetes and dietary long chain polyunsaturated fatty acids (LC-PUFAs) on hippocampal N-methyl-D-aspartate (NMDA) receptor subunit expression and lipid peroxidation. MDA level was significantly increased after 8 weeks of STZ-diabetes. LC-PUFAs administration significantly reduced MDA levels in diabetic rats. NR2A and NR2B protein concentrations were significantly decreased by about 30% in diabetic rats. Dietary LC-PUFAs partially restored NR2A and NR2B in diabetic rats whereas the most significant increase was seen in nondiabetic rats. Consequently, dietary LC-PUFAs can partially restore hippocampal NMDA receptors and decrease lipid peroxidation in diabetes. LC-PUFAs are thus a possible prophylactic means for preventing the cognitive deficiencies of diabetes.

Superoxide dismutase and glutathione peroxidase in erythrocytes of patients with iron deficiency anemia: effects of different treatment modalities.

AIM: To test whether the activities of erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) can be affected by oral iron (OI) treatment, parenteral iron (PI) treatment, and parenteral iron treatment with vitamin E supplementation (PIE) in iron deficiency anemia. METHODS: Twenty-eight patients with iron deficiency anemia and 18 healthy controls were included in the study. Anemic patients were systematically allocated into 3 treatment groups. The first group (n=8) received OI, the second group (n=10) PI, and the third group (n=10) PIE. SOD and GSH-Px activities were determined using commercial kits. RESULTS: Before the treatment, SOD activity was significantly lower in anemic patients than in the control group (Kruskal-Wallis test, p<0.05). After the treatment, SOD activity significantly increased in all three patient groups and reached the values found in the control group (Wicoxon signed-rank test, p=0.017 for OI, p=0.047 for PI, and p=0.037 for PIE group). Before the treatment, GSH-Px activities in anemic patients were similar to that of control group (Kruskal-Wallis test, p>0.05). Although there was no significant decrease in GSH-Px activity after OI treatment, both PI and PIE treatments significantly decreased GSH-Px activity (Wilcoxon signed-ranks test, p=0.007 for PI and p=0.005 for PIE). PIE was more effective than PI treatment in maintaining GSH-PX activity. CONCLUSION: Oral iron treatment improved the iron deficiency anemia and recovered antioxidant defense system by increasing SOD activity and maintaining GSH-Px activity at normal level. When parenteral iron treatment is inevitable, vitamin E supplementation together with PI treatment may be effective in partially restoring the antioxidant status in this type of anemia.