Effect of zinc and melatonin supplementation on cellular immunity in rats with toxoplasmosis

The effects of zinc (Zn) and/or melatonin supplementation on cellular immunity were investigated in rats infested with Toxoplasma gondii. Fifty Sprague-Dawley male rats were used for this study. All animals were fed a normal diet, ad libitum, containing 97 mg Zn/kg. They were divided into five experimental groups, as follows. Group I (n=10) received intraperitoneal injections of zinc sulfate at a dose of 3 mg/kg/d for 3 wk. Group II (n=10) received intraperitoneal injections of melatonin at a dose of 3 mg/kg/d for 3 wk. Group III (n=10) received intraperitoneal injections of zinc sulfate (3 mg/kg/d) and melatonin (3 mg/kg/d) for 3 wk. Group IV (n=10) was infested controls. Group V (n=10) was healthy controls. There were no differences in the percentage of CD3+ lymphocytes among all groups. For groups I–III, the CD4+ and CD8+ ratios were higher than those of the groups IV and V controls (p<0.01). Similarly, the total lymphocyte ratios in groups I–III were higher than those of infested and healthy controls (p<0.01). The total lymphocyte ratios in group III were significantly higher than those of groups I and II (p<0.01). The plasma Zn levels in the supplemented groups were significantly higher than those of control groups IV and V (p<0.01). These results suggest that melatonin and/or Zn supplementation may activate cellular immunity by stimulating CD4+ and CD8+ production in infected rats with T. gondii.     

Effects of zinc and melatonin deficiency on testicular tissue of rats

The present study was designed to investigate the effects of zinc and/or melatonin deficiency on rat testes. A total of 24 adult male Sprague-Dawley rats were used in this study. The rats were divided into four groups of six rats each, as follows: (I) controls, (II) zinc deficient, (III) pinealectomized, zinc normal, and (IV) pinealectomized, zinc deficient. The plasma zinc levels in the control group were higher than in all the other groups (p<0.01), and those of the zinc-deficient groups II and IV were significantly lower than for group III (p<0.01). The melatonin levels in the controls were also significantly higher than for all other groups (p<0.01) There was no significant difference in sperm production between the controls and the group of animals that had no epiphysis. A significant suppression was observed in the spermatogenetic activity of the zinc-deficient groups (p<0.01). The suppression was higher in group II than in group IV. These results indicate that testicular damage caused by zinc deficiency may be reduced by melatonin deficiency.     

Effects of zinc deficiency and supplementation on malondialdehyde and glutathione levels in blood and tissues of rats performing swimming exercise

The aim of the study was to investigate the effects of zinc deficiency and supplementation on lipid peroxidation and glutathione levels in blood and in some tissues of rats performing swimming exercise. Forty adult male Sprague-Dawley rats were divided into four groups: group 1, zinc-deficient consisted of swimming rats; group 2 consisted of zinc-supplemented swimming rats; groups 3 and 4 were the swimming and nonswimming controls, respectively. The levels of malondialdehyde and glutathione were measured after 4 wk of zinc-deficient or zinc-supplemented diet and 30 min of swimming exercise daily. The erythrocyte glutathione levels of groups 2 and 4 were significantly higher than those of groups 1 and 3 (p<0.01). The plasma malondialdehyde level of group 1 was significantly higher than all other groups. The glutathione levels in liver, kidney, striated muscle, and testes of group 2 were higher than in the other groups (p<0.01) and higher in kidney and striated muscle of group 3 than in groups 1 and 4 (p<0.01). The tissue malondialdehyde levels of striated muscle, liver, kidney, and testes of group 1 were significantly higher than for all other groups (p<0.01). Our findings suggest that both swimming exercise and zinc deficiency result in an increase of lipid peroxidation in tissues and that zinc supplementation prevents these alterations by the activation of the antioxidant system.     

Effect of zinc deficiency and supplementation on lipid peroxidation of renal tissue in ovariectomized rats

The aim of this study was to investigate how zinc deficiency and supplementation affects lipid peroxidation in the renal tissue in ovariectomized rats. Four study groups were formed with 10 Spraque-Dawley rats each. Two of the groups served as normal and ovariectomized controls; the other two were ovariectomized rats that were zinc deficient and zinc supplemented, respectively. The zinc-deficient ovariectomized rats showed greater renal and plasma lipid peroxidation, as indicated by higher malondialdehyde levels than all other groups (p<0.05). These values were higher in the ovariectomized controls than those of the normal controls and of the ovariectomized, zinc-supplemented groups (p<0.05), which, in, turn, showed no significant differences of their respective renal and plasma malondialdehyde values. The renal and erythrocyte glutathione levels in the zinc-supplemented rats were higher than those in all other groups (p<0.05). The zinc-deficient group had the lowest renal and erythrocyte glutathione levels (p<0.05). The renal tissue zinc levels in the ovariectomized rats were higher than those in the zinc-deficient animals, but lower than in the normal controls and zincsupplemented rats (p<0.05). The zinc-supplemented animals had the highest renal tissue zinc levels (p<0.05). The results of this study suggest that zinc deficiency increases renal tissue damage in ovariectomized rats and that zinc supplementation can be used to prevent this condition.     

Zinc deficiency decreases plasma erythropoietin concentration in rats

In 1985, Paterson and Bettger found hypoplastic hematopoiesis in severely zinc-deficient rats. Therefore, we investigated plasma erythropoietin concentration in zinc-deficient rats. Forty 4-wk-old male Sprague-Dawley rats were assigned into 4 dietary treatment groups of 10 for the 4-wk study: zinc-deficient group (4.5 mg zinc and 35 mg iron/kg; −Zn), iron-deficient group (30 mg zinc/kg, no supplemental iron; −Fe), zinc/iron-deficient group (4.5 mg zinc/kg, no supplemental iron; −Zn−Fe), and control group (AIN-93G; Cont). Water intake determined at d 19 was similar among all treatment groups. At d 27–28, bioimpedance was measured. The intracellular water/extracellular water ratio was significantly increased in the −Zn group (p<0.05). Compared to the Cont, group, the plasma erythropoietin concentration was increased by iron deficiency and decreased by zinc deficiency (p<0.01). Hematocrit was significantly decreased in both the −Fe and −Zn−Fe groups and was significantly increased in the −Zn group (p<0.01). Transferrin saturation in the −Fe and −Zn−Fe groups was significantly lower than the Cont group (p<0.01), and that of the −Zn group was highest among all groups. The low plasma erythropoietin concentration might account for depressed hematopoiesis associated with zinc deficiency.     

The Effects of Exercise and Zinc Deficiency on Some Elements in Rats

The objective of the present study was to determine the effects of exercise and zinc deficiency on some elements in rats. Forty adult male Sprague–Dawley species male rats were allocated to four groups as follows: Group 1: control, Group 2: zinc-deficient, Group 3: exercise in which exercise group fed with a normal diet, Group 4: zinc-deficient exercise, exercise group fed by a zinc-deficient diet for 15 days. After the procedure ended, rats in groups 3 and 4 were exercised on the treadmill for 60 min at a speed of 6 m/min until the exhaustion. The rats were decapitated 48 h after exercise together with their controls, and blood samples were collected to determine copper (Cu), iron (Fe), magnesium (Mg), calcium (Ca), and phosphorus (P) levels. The highest Cu and Fe values in the serum were obtained in group 2 (p < 0.01). The levels of these elements in group 4 were lower than those in group 2 and higher than the levels in groups 1 and 3 (p < 0.01). Serum Mg levels did not differ significantly between groups. Group 4 had the lowest serum Ca and P levels (p < 0.01). These same parameters in Group 2 were higher than those in group 4 but significantly lower than those in groups 1 and 3 (p < 0.01). There was no significant difference between Ca and P levels of groups 1 and 3. The results of the study indicate that zinc deficiency adversely affects copper, iron, calcium, and phosphorus mechanisms and that these adverse effects much more marked after an effort exercise.     

Both zinc deficiency and supplementation affect plasma melatonin levels in rats

At physiological levels, zinc and various hormones affect each other reciprocally. Reduction in zinc levels in pinealectomized rats suggests the relation between zinc and melatonin. The effect of both zinc deficiency and supplementation on plasma melatonin levels in rats were investigated in this study. The study was done in Sel?uk University, Experimental Medicine Research and Application Center. Twenty-four adult male Sprague Dawley rats were divided into 3 groups. Eight rats were fed with zinc-deficient diet. Zinc supplementation was administered intaperitoneally to 8 rats. The remaining 8 rats were used as controls. All rats sacrificed 3 weeks later. Plasma melatonin and zinc levels were determined. The plasma zinc levels of the zinc-supplemented group were higher than those of the other groups as expected (P<0.01). Similarly, the melatonin levels in the zinc-supplemented group were higher than those in the other groups. A significant decrease was observed in melatonin levels of the zinc-deficient group compared to the control and zinc-supplemented group (P<0.01). The results of this study suggest that zinc deficiency decreases the melatonin levels and zinc supplementation may increase the plasma melatonin levels in rats.     

Protection of Selenium on Hepatic Mitochondrial Respiratory Control Ratio and Respiratory Chain Complex Activities in Ducklings Intoxicated with Aflatoxin B<Subscript>1</Subscript>

To investigate the protection of selenium on hepatic mitochondrial functions, 90 7-day-old ducklings were randomly divided into three groups (groups I–III). Group I was used as a blank control. Group II was administered with aflatoxin B₁ (0.1 mg/kg body weight). Group III was administered with aflatoxin B₁ (0.1 mg/kg body weight) plus selenium (sodium selenite, 1 mg/kg body weight). All treatments were given once daily for 21 days. The results showed that the activities of hepatic mitochondrial complexes I–IV in group II ducklings significantly decreased when compared with group I (P < 0.01). Furthermore, the activities of hepatic mitochondrial complexes I–IV in group III significantly increased when compared with group II (P < 0.05). The hepatic mitochondrial respiratory control ratio (RCR) in group II ducklings significantly decreased when compared with group I (P < 0.01). In addition, the hepatic mitochondrial RCR in group III significantly increased when compared with group II (P < 0.05). These results revealed that the aflatoxin B₁ significantly induced hepatic mitochondrial dysfunction in the activities of hepatic mitochondrial respiratory chain complexes I–IV and the RCR in ducklings. However, sodium selenite could significantly ameliorate the negative effect induced by aflatoxin B₁.     

Changes of total content of magnesium and zinc status in patients with chronic toxoplasmosis

The aim of this study was to investigate the effects of the Toxoplasma gondii infection on the total content of the essential elements Zn and Mg levels. Plasma zinc and magnesium concentrations were measured in 158 patients whose anti-T gondii IgG antibodies were positive. Scores were obtained for the patients and their age- and sex-matched 82 sero-negative healthy controls. The mean concentration of Mg in blood was significantly lower in sero-positive patients than in their controls both in females (p<0.01) and males (p<0.01). The average Zn concentration in seropositive female patients was 0.72±0.2 mg/L and 0.65±0.1 mg/L in controls (p>0.05). The mean values of the Zn in blood were 1.00±0.3 mg/L in seropositive male patients and 0.84±0.2 in controls (p>0.05). No correlation could be demonstrated between age and mean values of Zn and Mg in both sero-positive females/males and controls (p>0.05). No significant correlation could be found between blood Zn and Mg levels in seropositive female/male patients and controls (p>0.05). Mg levels were found to be clearly decreased in the patients with chronic toxoplasmosis, whereas no change was observed in Zn levels.     

Effects of repeated desflurane and sevoflurane anesthesia on enzymatic free radical scavanger system

Background: To investigate the possible effects of repeated sevoflurane and desflurane anesthesia on hepatocellular system by evaluating the free radical metabolism, hepatocellular enzymes and histopatholgical changes in rats. Methods: Four groups of animals were studied. Sevoflurane 2% (v/v) and desflurane 6% (v/v) in air/O₂ were administered to animals in group II (n = 9) and III (n = 9) respectively. 100% (v/v) O₂ was administered in group IV (n = 9). Administration was done for 60 minutes over 3 days. Nine animals were allocated to control group (group I), superoxide dismutase (SOD), catalase (CAT), glutathion peroxidase (GSH-Px), glutathione-s-transferase (GST) and thiobarbituric acid reactive substances (TBARS) were studied. Also electron microscopy was performed. Results: Catalase, SOD, GSH-Px, GST activities and TBARS levels were significantly higher in groups II and III than in group I (p < 0.05). All parameters were significantly higher in groups II versus group IV (p < 0.05). On the other hand, SOD, GSH-Px and GST activities were significantly elevated in group III than IV, but CAT activity and TBARS levels were not significantly. Catalase, SOD, GSH-Px, GST but not TBARS levels were significantly higher in groups II and III than in group IV (p < 0.05). TBARS levels were higher in group III than in group IV, but this elevation was not statistically significant. CAT, SOD and GSH-Px activities were significantly higher in groups II than in group III (p < 0.05). Conclusion: Although electron microscopy findings were similar for group II and III, we can conclude that sevoflurane might cause more cellular damage than desflurane by causing higher activation of free radical metabolising enzymes.     

Effect of long-term swimming exercise on zinc,magnesium, and copper distribution in aged rats

Trace element content of different tissues might be altered by both age and exercise training. We aimed to determine the effects of a 1-yr swimming protocol (60 min/d, 5 day/wk) on tissue levels and the distribution of zinc (Zn), magnesium (Mg), and copper (Cu) in aging rats. Three groups were formed: sedentary and trained old groups and a young control group. Tissue Zn, Mg, and Cu concentrations were measured in the kidney, heart, liver, lungs, and gastrocnemius and soleus muscles. Kidney zinc concentration significantly decreased in the sedentary old group compared to the young control group (p<0.01) and was significantly higher in the trained old group compared to the sedentary old group (p<0.01), whereas Zn levels in the soleus muscle significantly increased in the sedentary old group in comparison to young controls (p<0.05). Tissue Mg concentrations remained unchanged. The sedentary old group exhibited a significant decrease in kidney Cu concentration compared to the young control group (p<0.01). Although kidney Cu levels also decreased in trained old rats in comparison to young controls (p<0.05), they were significantly higher than in sedentary old rats (p<0.01). The decrease in kidney Zn and Cu content as a result of aging was partly prevented by long-term swimming exercise.     

Orally administered tryptophan and experimental type 2 diabetes

There is a link between diabetes and oxidative stress. Hyperglycaemia leads to free radical generation and alterations of endogenous antioxidants. Our aim is to study the effect of orally administered L-tryptophan (TRP), the melatonin precursor, an endogenous antioxidant, on circulating levels of glycaemia, insulin and melatonin, and on the superoxide dismutase and catalase antioxidant systems in non-diabetic (ND) and type 2 diabetic (n5-STZ) male Wistar rats.At 19:30 every day for 15 days, TRP (125 mg/kg body weight) was administered orally. At 09:00 every two days the glycaemia was measured and every day the intake of food and water was recorded. At the beginning and end of treatment (at 09:00; 21:00; 02:00) plasma insulin and melatonin levels were measured, and (at 09:00) the enzymatic activities of catalase and superoxide dismutase (SOD) in erythrocytes were also measured. Glycaemia values were greater (p < 0.01) in n5-STZ rats than in ND rats, while insulin levels were lower (p < 0.05) at all times studied and these parameters were not altered by the TRP administration. Melatonin levels at 02:00 were lower in n5-STZ than in ND rats (p < 0.05). The TRP administration did not modify the circulating melatonin levels in ND rats, but raised (p < 0.01) the levels at 02:00 in the treated n5-STZ group. In ND rats after TRP administration there was a decline in catalase activity (p < 0.05), while in n5-STZ rats there was a rise (p < 0.01) at the end of treatment. However, there were no significant changes in SOD activity. There was increased food intake (g/day) in the treated n5-STZ group (p < 0.01). In conclusion, the oral administration of TRP did not modify glycaemia or insulinaemia levels, but raised melatonin levels in diabetic rats at 02:00, lowered catalase activity in ND rats but raised it in n5-STZ rats, and increased food intake in n5-STZ rats. (Mol Cell Biochem 261: 57–61, 2004)     

Effect of Pineal Proteins at Different Dose Level on Fluoride-Induced Changes in Plasma Biochemicals and Blood Antioxidants Enzymes in Rats

Pineal glands secrets melatonin and various proteins and peptides which has many physiological functions. In keeping with this view, present experiment was conducted to know the effect of buffalo (Bubalus bubalis) pineal proteins (PP) at different dose level on fluoride-induced changes in plasma biochemicals and blood antioxidants enzymes in female rats. For this, we took 30 adult female Wistar rats (133–145 g body weights, BW) and divided into five groups (control, group I; 150 ppm fluoride (F), group II; F+ 50 µg pineal proteins, group III; F+ 100 µg PP, group IV; F+ 200 µg PP, group V). We administered fluoride (150 ppm, drinking water) and F+ pineal proteins at 50, 100, and 200 µg/kg BW, i.p. daily for 21 days. Blood samples were collected at the end of the experiments to estimate plasma glucose, proteins, F, lipid peroxidation (LPO), alkaline phosphatase (ALP), and acetyl cholinesterase (AChE) activity. Red blood cells (RBCs) were separated for analysis of LPO, AChE, catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx), and glutathione reductase (GR) in different groups of animals. Total plasma glucose and protein level did not significantly change in F-treated rats. Plasma ALP and F level were significantly (p?<?0.05) high in group II as compared with control and groups III, IV, and V. Administration of PP at different dose level significantly (p?<?0.05) reduced the F concentration and ALP activity. Plasma and RBCs AChE activity was significantly (p?<?0.05) reduced in F-treated animals as compared with control rats and significantly (p?<?0.05) elevated on exogenous administration of PP (groups III and IV). Plasma and RBCs LPO level was significantly (p?<?0.05) high in F-alone-treated rats, and PP caused significant (p?<?0.05) reduction of LPO in groups IV and V. However, PP treatment in group IV brought better amelioration of F-induced high LPO than in groups III and V. At no dose level, PP-ameliorated F-induced depression of RBCs GSH, CAT, GR, and GPx level. Interestingly, SOD activity was elevated in dose-dependent manner at different dose level of PP in groups III, IV, and V than control and F-administered rats. These findings clearly indicate the beneficial effects of buffalo pineal proteins on fluoride-induced adverse changes in certain plasma biochemical and blood antioxidant systems of rats. It further indicates that PP has dose-dependent ameliorative function against F-induced adverse effects in plasma and blood.     

Microelements in seminal plasma of infertile men infected with Ureaplasma urealyticum

The purpose of this study was to assess the association among male infertility, infection of Ureaplasma urealyticum (Uu), and microelements in seminal fluid. Semen analysis and cultivation of Uu were carried out on 160 samples of seminal fluid. The concentrations of microelements, such as arsenic (As), molybdenum (Mo), magnesium (Mg), lead (Pb), copper (Cu), cadmium (Cd), and zinc (Zn) in the samples were measured by an inductively coupled plasma quantometer (ICP). The ratios Cu/Zn and Cd/Zn in the poor spermatic quality group were obviously higher than those in seminal plasma of the group with normal spermatic quality (p<0.01 and p<0.05, respectively), whereas the concentrations of As, Mg, Mo, and Pb showed no difference in the two groups. The ratios Cu/Zn and Cd/Zn and the concentrations of As and Mg in seminal plasma infected with Uu were markedly higher than those not infected with Uu (p<0.05, p<0.01, p<0.05, and p<0.05, respectively), whereas the concentrations of Mo and Pb showed no statistical difference. The ratios Cu/Zn and Cd/Zn and the concentrations of As and Mg in seminal plasma of the semen with poor spermatic quality and Uu infection were obviously higher than those not infected with Uu (p<0.05), whereas the concentrations of Mo and Pb showed no statistical difference. Abnormally high ratios Cu/Zn and Cd/Zn as well as an overdose of As were found to be predisposed to Uu infection. Uu infection resulted in an increase of the ratios Cu/Zn and Cd/Zn and the concentrations of As and Mg in seminal fluid, which therefore caused spermatic quality decline.     

A fibre cocktail of fenugreek, guar gum and wheat bran reduces oxidative modification of LDL induced by an atherogenic diet in rats

Background LDL (low-density lipoprotein) oxidation is a key trigger factor for the development of atherosclerosis. Relatively few studies exist on the impact of dietary fibre on LDL oxidation. This study was undertaken to evaluate the influence of a novel fibre mix of fenugreek seed powder, guar gum and wheat bran (Fibernat) on LDL oxidation induced by an atherogenic diet. Method Male Wistar albino rats were administered one of the following diets: (1) a control diet that was fibre-free (Group I); (2) an atherogenic diet containing 1.5% cholesterol and 0.1% cholic acid (Group II) or (3) an atherogenic diet supplemented with Fibernat (Group III). Peroxidative changes in low-density lipoprotein (LDL) and the oxidative susceptibility of LDL and the LDL + VLDL (very low-density lipoprotein) fraction were determined. As a corollary to the oxidative modification theory, the titer of autoantibodies to oxidised LDL (oxLDL) was determined at various time points of the study. In addition, plasma homocysteine (tHcy) and lipoprotein (Lp (a)), apolipoprotein (apoB), cholesterol, triglyceride, phospholipid and α-tocopherol content of LDL were determined. Results A decrease in malonaldehyde (MDA) content (p < 0.05) and relative electrophoretic mobility (REM) of LDL was observed in the group III rats as compared to the group II rats. An increase in lag time to oxidation (p < 0.01) and decrease in maximum oxidation (p < 0.01) and oxidation rate (p < 0.01) were observed in the LDL + VLDL fraction of group III rats. In group II rats, formation of autoantibodies to oxLDL occurred at an earlier time point and at levels greater than in the group III rats. Fibernat, had a sparing effect on LDL α-tocopherol, which was about 51% higher in the group III rats than in the group II rats; apo B content of LDL was reduced by 37.6% in group III rats. LDL of group III rats displayed a decrease in free and ester cholesterol (p < 0.01) as compared to that of group II. A decrease in plasma homocysteine (p < 0.01) and an increase in GSH (p < 0.05) were also observed in group III rats when compared with that of group II. Conclusion Fibernat administration appears to combat oxidative stress resulting in a trend to lower oxidative modification of LDL. In addition, the cholesterol and apo B content of LDL were reduced significantly with a sparing effect on LDL α-tocopherol. This novel fibre preparation could be an effective diet therapy and therefore needs further investigation.     

Effects of carvacrol on defects of ischemia-reperfusion in the rat liver

Many plants found in nature have been used to treat various illnesses. One such plant is oregano (Kekik in Turkish). Health beneficial effects of carvacrol obtained from oregano oil have been shown scientifically. We have investigated the comparative effects of carvacrol in the liver of rats subjected to ischemia-reperfusion defect, with silymarin. To test the effects we formed four groups using male Wistar albino rats. Group I was control. The other three groups of animals were administered 60 min prior to surgical operation single doses of physiological serum, carvacrol and silymarin, respectively. Group II, III and IV animal were subjected to 45 min long liver ischemia and 60 min reperfusion. Blood and tissue samples were collected for biochemical and histological analysis following the test.AST and ALT values obtained after biochemical analysis of the serums showed statistically significant difference in group II than the other three groups. A statistical evaluation of the serum AST levels among the groups II, III and IV showed that both groups III and IV which had no difference in between were significantly different in a positive way from group II (p<0.001). As to the serum ALT levels, difference between group II and group III (p<0.001) and group II and group IV (p<0.01) was found significant. No statistical difference was observed in groups I, III and IV for GSH, MDA and CAT levels of the liver. A statistical evaluation of the GSH level in group III and group IV was found to be significantly different from group II (p<0.001) without any difference between them. A similar evaluation for MDA and CAT levels among the revealed no difference between group III and group IV, however, group II showed difference with group II and group IV (p<0.05).Histological findings were in harmony with the biochemical results. We conclude that carvacrol protects the liver against defects caused by ischemia and reperfusion, and carvacrol is not hepatotoxic at the applied dosage.     

Neuroprotective effect of melatonin on radiation-induced oxidative stress and apoptosis in the brainstem of rats

This study aimed to determine the effects of melatonin on irradiation-induced apoptosis and oxidative stress in the brainstem region of Wistar rats. Therefore, the animals underwent whole-brain X-radiation with a single dose of 25 Gy in the presence or absence of melatonin pretreatment at a concentration of 100 mg/kg BW. The rats were allocated into four groups (10 rats in each group): namely, vehicle control (VC), 100 mg/kg of melatonin alone (MLT), irradiation-only (RAD), and irradiation plus 100 mg/kg of melatonin (RAM). An hour before irradiation, the animals received intraperitoneal (IP) melatonin and then were killed after 6 hr, followed by measurement of nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and total antioxidant capacity (TAC) in the brainstem region. Furthermore, the western blot analysis technique was performed to assess the caspase-3 expression level. Results showed significantly higher MDA and NO levels in the brainstem tissues for the RAD group when compared with the VC group (p < .001). Moreover, the irradiated rats exhibited a significant decrease in the levels of CAT, SOD, GPx, and TAC (p < .01, p < .001, p < .001, and p < .001, respectively) in comparison to the VC group. The results of apoptosis assessment revealed that the expression level of caspase-3 significantly rose in the RAD group in comparison with the VC group (p < .001). Pretreatment with melatonin ameliorated the radiation-induced adverse effects by decreasing the MDA and NO levels (p < .001) and increasing the antioxidant enzyme activities (p < .001). Consequently, the caspase-3 protein expression level in the RAM group showed a significant reduction in comparison with the RAD group (p < .001). In conclusion, melatonin approximately showed a capacity for neuroprotective activity in managing irradiation-induced oxidative stress and apoptosis in the brainstem of rats; however, the use of melatonin as a neuroprotective agent in humans requires further study, particularly clinical trials.     

Studies of five microelement contents in human serum, hair, and fingernails correlated with aged hypertension and coronary heart disease

Using atomic absorption spectrometry (AAS), five microelements in human serum, hair, and fingernails of aged hypertension, coronary heart disease (diseased group) and aged health control (healthy group) were detected. Results of the t-test are as follows: The iron, zinc, and cadmium contents and Zn/Cu (mol/mol) ratio of the diseased group were significantly higher than that of the healthy group in serum (p<0.01, p<0.05, p<0.01, and p<0.05, respectively); the chromium contents in the serum, hair, and fingernails (p<0.05, p<0.01, and p<0.05, respectively); the iron and zinc contents in the hair and fingernails (p<0.01, p<0.001, p<0.05, and p<0.01 respectively) and Zn/Cu ratio in the hair (p<0.01) of the diseased group were significantly lower than that of the healthy group. Pathogenic factors of cardiovascular disease have three probabilities: (1) The iron contents of the diseased group were higher than that of the healthy group in serum and lower in hair and fingernails (i.e., abnormal iron metabolism); (2) the zinc contents and the Zn/Cu ratio of the diseased group were higher than that of the healthy group in the serum and the zinc contents in the hair and fingernails and the Zn/Cu ratio in the hair of the diseased group were significantly lower than that of the healthy group; (3) the chromium contents of the diseased group were significantly lower than that of the healthy group in the serum, hair, and fingernails.     

Zinc prevention of electromagnetically induced damage to rat testicle and kidney tissues

The aim of this study was to investigate the extent of lipid peroxidation when zinc is administered to rats periodically exposed to a 50-Hz electromagnetic field for 5 min at a time over a period of 6 mo. Twenty-four Sprague-Dawley adult male rats were subdivided in groups of eight animals each. Group 1 served as untreated controls, group 2 was exposed to an electromagnetic field but received no additional treatment, and group 3 was exposed to electromagnetic radiation and treated with 3-mg/kg daily intraperitoneal injections of zinc sulfate. The erythrocyte glutathione activity (GSH) and the plasma, testicle, and kidney tissue levels of zinc (Zn) and of malondialdehyde (MDA) were measured in all of the animals. The plasma and testicle MDA levels in group 2 were higher than those in groups 1 and 3, with group 3 values significantly higher than those in group 1 (p<0.001). The kidney MDA levels in group 2 were higher than in groups 1 and 3 (p<0.001). The erythrocyte GSH level was lower in group 2 than in groups 1 and 3, with group 1 significantly lower than group 3 (p<0.001). In testicle and kidney tissues, the GSH levels in group 1 were lower than for groups 2 and 3, with group 2 significantly lower than group 3 (p<0.001) The plasma zinc levels were highest in group 3, followed by group 1 and group 2, which showed the lowest value (p<0.001). These results indicate that testicle and kidney tissue damage caused by periodic exposure to an electromagnetic field are ameliorated or prevented by zinc supplementation.     

The Effects of Chromium Histidinate on Mineral Status of Serum and Tissue in Fat-Fed and Streptozotocin-Treated Type II Diabetic Rats

The present study was conducted to investigate the effects of chromium histidinate (CrHis) against experimentally induced type II diabetes and on chromium (Cr), zinc (Zn), selenium (Se), manganese (Mn), iron (Fe), and copper (Cu) in serum, liver, and kidney of diabetic rats. The male Wistar rats (n = 60, 8 weeks old) were divided into four groups. Group I received a standard diet (12% of calories as fat); group II were fed standard diet and received CrHis (110 mcg CrHis/kg body weight per day); group III received a high-fat diet (HFD; 40% of calories as fat) for 2 weeks and then were injected with streptozotocin (STZ) on day 14 (STZ, 40 mg/kg i.p.; HFD/STZ); group IV were treated as group III (HFD/STZ) but supplemented with 110 mcg CrHis/kg body weight per day. The mineral concentrations in the serum and tissue were determined by atomic absorption spectrometry. Compared to the HFD/STZ group, CrHis significantly increased body weight and reduced blood glucose in diabetic rats (p < 0.001). Concentrations of Cr, Zn, Se, and Mn in serum, liver, and kidney of the diabetic rats were significantly lower than in the control rats (p < 0.0001). In contrast, higher Fe and Cu levels were found in serum and tissues from diabetic versus the non-diabetic rats (p < 0.001). Chromium histidinate supplementation increased serum, liver, and kidney concentrations of Cr and Zn both in diabetic and non-diabetic rats (p < 0.001). Chromium supplementation increased Mn and Se levels in diabetic rats (p < 0.001); however, it decreased Cu levels in STZ-treated group (p < 0.001). Chromium histidinate supplementation did not affect Fe levels in both groups (p > 0.05). The results of the present study conclude that supplementing Cr to the diet of diabetic rats influences serum and tissue Cr, Zn, Se, Mn, and Cu concentrations.