Dose and time dependent effects of ethanol on antioxidant system in rat testes

Effect of simultaneous coffee/caffeine and ethanol administration on sperm quality and reproductive hormones: an experimental study in Sprague Dawley rats

Chronic alcohol or coffee/caffeine consumption has been associated with negative effects on male reproductive system. The present study evaluated the possible interaction (combination treatment) of coffee/caffeine and alcohol and its resultant consequence on sperm parameters in rats. Ten groups of adult Sprague Dawley rats (n = 5 per group) were orally gavaged with different quantities of coffee (≈5, 10, and 20 mg/kg caffeine); 30% v/v ethanol (0.5, 1, and 2 g/kg); coffee + ethanol or vehicle (distilled water) daily for 60 days. Sperm parameters, serum sex hormone levels, together with antioxidants and lipid peroxidation status of testis homogenate were evaluated. Single and combined administration of coffee/caffeine and ethanol caused a reduction in sperm count dose-dependently (p = 0.0002), but this effect was highest in the combined treatment. Sperm viability, motility, and morphology were unaffected by coffee or ethanol administration, but the combination produced detrimental effects on them. While changes in follicle stimulating hormone were not significant, testosterone and luteinizing hormone levels were decreased significantly and dose-dependently in all experimental groups (p < 0.05-0.0001). This effect was most pronounced in the groups that received the combination. Testicular superoxide dismutase and catalase activities, and reduced glutathione and malondiadehye (MDA) levels were not affected by coffee/caffeine, but ethanol decreased (p < 0.05) the antioxidants and elevated MDA levels mostly at 2 g/kg. The combination reduced (p < 0.0001) the antioxidants and increased MDA levels in testis homogenates at all doses. Combination of coffee/caffeine and ethanol potentiates their detrimental effects on sperm quality and reproductive hormones via reduction in testicular antioxidants activities and elevation of lipid peroxidation in rats.

Clinal variation in investment into reproduction versus maintenance suggests a 'pace-of-life' syndrome in a widespread butterfly

Extreme weather events such as heat waves are predicted to increase in the course of anthropogenic climate change. Widespread species are exposed to a variety of environmental conditions throughout their distribution range, often resulting in local adaptation. Consequently, populations from different regions may vary in their capacity to deal with challenging conditions such as thermal stress. In this study, we investigated clinal variation in body size, fecundity, and oxidative markers along a pan-European latitudinal gradient in the green-veined white butterfly Pieris napi, and additionally gene expression in German individuals. We exposed butterflies from replicated Italian, German, and Swedish populations to cold, control, or hot temperatures for 24 h. Under hot conditions, molecular chaperones were up-regulated, while oxidative damage remained unaffected and levels of the antioxidant glutathione (GSH) were reduced under cold and hot conditions. Thus, the short-term exposure to heat stress did not substantially affect oxidative balance. Moreover, we found decreased body size and fecundity in cooler compared with warmer regions. Interestingly, oxidative damage was lowest in Swedish animals exhibiting (1) high levels of GSH, (2) low early fecundity, and (3) low larval growth rates. These results suggest that Swedish butterflies have a slower life style and invest more strongly into maintenance, while those from warmer regions show the opposite pattern, which may reflect a 'pace-of-life' syndrome.

NADPH oxidase contributes to oxidative damage and mitochondrial impairment induced by acute ethanol treatment in rat hippocampal neurons

Acute ethanol treatment induces neurodegeneration in cultured neurons and can lead to brain damage in animal models. Neuronal cells exposed to ethanol showed an increase in reactive oxygen species (ROS), oxidative damage and mitochondrial impairment contributing to synaptic failure. However, the underlying mechanisms of these events are not well understood. Here, we studied the contribution of NADPH oxidase, as a relevant source of ROS production in the brain, to mitochondrial impairment and oxidative stress induced by ethanol. We used primary hippocampal neurons subjected to an acute treatment of ethanol at increasing concentrations (25, 50, and 75 mM, 24 h), and we evaluated ROS production, mitochondrial function, and synaptic vesicle activity. Our studies showed that after ethanol administration, hippocampal neurons presented an increase in ROS levels, mitochondrial dysfunction, calcium handling defects, and synaptic impairment. Interestingly, treatment with the NADPH inhibitor, apocynin, significantly prevented oxidative stress, mitochondrial dysfunction, and the impairment of synaptic vesicle activity induced by ethanol treatment. These results indicate that NADPH oxidase could be a key participant in the molecular mechanism by which alcohol affects the brain.

The Improvement Effects of Gordonia bronchialis on Male Fertility of Rats with Diabetes Mellitus Induced by Streptozotocin

Background: This study evaluated the possible protective effects of Gordonia bronchialis (Gb) on oxidative stress and some subsequent alterations on testis from rats undergoing an experimentally induced type 1 diabetes. Methods: A total of 40 male rats were randomly divided into four groups of ten. Diabetes was induced by injection of 55 mg/kg streptozotocin in 30 rats. Oral administration of Gb at dose of 105 (low dose) and 107 (high dose) CFU/rat was performed in two groups continuously for 14 days. The third and fourth groups received normal saline as the diabetic and healthy control groups, respectively. The blood and testicular tissue samples were taken on the 14th and 21st days post treatment for biochemical and histopathological evaluations. Results: Significant differences were found in blood glucose level, insulin, IL-6 and TNF-α values together with catalase and superoxide dismutase activities and malondialdehyde level in the diabetic group in comparison with healthy and Gb recipient groups. Moreover, the histopathological lesions observed in the diabetic rats mainly included basement membrane thickening, decreased number of Sertoli cells, and severe reduction of spermatogenesis markedly attenuated in Gb-treated rats. Conclusion: Taken together, it seems that oral administration of Gb could ameliorate testicular damage associated with some related parameters in the diabetic animal model.

Hepatoprotective potential of chestnut bee pollen on carbon tetrachloride-induced hepatic damages in rats

Bee pollen has been used as an apitherapy agent for several centuries to treat burns, wounds, gastrointestinal disorders, and various other diseases. The aim of our study was to investigate the hepatoprotective effects of chestnut bee pollen against carbon tetrachloride (CCI₄)-induced liver damage. Total phenolic content, flavonoid, ferric reducing/antioxidant power, and DPPH radical activity measurements were used as antioxidant capacity determinants of the pollen. The study was conducted in rats as seven groups. Two different concentrations of chestnut bee pollens (200 and 400 mg/kg/day) were given orally and one group was administered with silibinin (50 mg/kg/day, i.p.) for seven days to the rats following the CCI₄ treatment. The protective effect of the bee pollen was monitored by aspartate transaminase (AST) and alanine transaminase (AST) activities, histopathological imaging, and antioxidant parameters from the blood and liver samples of the rats. The results were compared with the silibinin-treated and untreated groups. We detected that CCI₄ treatment induced liver damage and both the bee pollen and silibinin-treated groups reversed the damage; however, silibinin caused significant weight loss and mortality due, severe diarrhea in the rats. The chestnut pollen had showed 28.87 mg GAE/g DW of total phenolic substance, 8.07 mg QUE/g DW of total flavonoid, 92.71 mg Cyn-3-glu/kg DW of total anthocyanins, and 9 mg β-carotene/100 g DW of total carotenoid and substantial amount of antioxidant power according to FRAP and DPPH activity. The results demonstrated that the chestnut bee pollen protects the hepatocytes from the oxidative stress and promotes the healing of the liver damage induced by CCI₄ toxicity. Our findings suggest that chestnut bee pollen can be used as a safe alternative to the silibinin in the treatment of liver injuries.

Protective effect of ascorbic acid against ethanol-induced reproductive toxicity in male guinea pigs

The present study was undertaken to elucidate the effect of ascorbic acid on alcohol-induced reproductive toxicity and also to compare it with that of abstention. A total of thirty-six male guinea pigs were divided into two groups and were maintained for 90 d as control and ethanol-treated groups (4 g/kg body weight (b.wt.)). After 90 d, ethanol administration was stopped and animals in the control group were divided into two groups and then maintained for 30 d as the control and control+ascorbic acid groups and those in the ethanol-treated group as ethanol abstention and ethanol+ascorbic acid (25 mg/100 g b. wt.) groups. Animals treated with ethanol showed a significant decline in sperm quality (P< 0·001), decreased activity of steroidogenic enzymes (P< 0·05) and reduced serum testosterone (P< 0·05), luteinising hormone and follicle-stimulating hormone levels, decrease in the activity of testicular succinate dehydrogenase, adenosine triphosphatase, sorbitol dehydrogenase and reduction in fructose content (P< 0·05). It also caused an increase in testicular malondialdehyde levels (P< 0·05) and decrease in the levels of glutathione content (P< 0·001) of testes. Ascorbic acid levels in testes and plasma were also reduced (P< 0·001) in ethanol-fed animals. Ascorbic acid supplementation altered all these parameters and produced a better and faster recovery from alcohol-induced reproductive toxicity than abstention. The mechanism of action of ascorbic acid may be by reducing the oxidative stress and improving antioxidant status, which eventually changed the microenvironment of testes and enhanced the energy needed for motility of sperms, improved the sperm morphology and elevated the testosterone and gonadotropin levels.

Effects of acute alcohol consumption and vitamin E co-treatment on oxidative stress parameters in rats tongue

The aim of this study was to evaluate the effects of acute alcohol consumption and vitamin E co-treatment upon oxidative stress parameters in rats tongue. Thirty-eight, Wistar rats were separated into five groups (alcohol, alcohol/vitamin E, control, Tween, vitamin E). Alcohol and alcohol vitamin E groups had the standard diet, and 40% alcohol on drinking water. Other groups were fed with the same standard diet and water ad libitum. Vitamin E was given by gavage to vitamin E and alcohol/vitamin E rats twice a week. Alcohol and control groups were subjected to saline gavage and Tween group to 5% Tween 80 solution, the vitamin E vehicle. At day 14, the animals were anesthetized and specimens were obtained from tongue. Lipid peroxidation (TBARS), protein oxidative damage, catalase (CAT) and superoxide dismutase (SOD) activities were quantified. Alcohol group decreased TBARS in relation to control group and alcohol vitamin-treated animals decreased TBARS when compared to Tween and vitamin E groups. SOD activity was lower and CAT activity was higher in animals treated with both alcohol and vitamin E. These results suggest that short-term alcohol consumption decreases lipid peroxidation levels. Alternatively, alcohol/vitamin E group increased CAT, showing the toxicity of this association.

Evaluation of effect of some corticosteroids on glucose-6-phosphate dehydrogenase and comparative study of antioxidant enzyme activities

Corticosteroids are anti-inflammatory drugs that are similar to the natural corticosteroid hormones produced by the cortex of the adrenal glands. The objective of this study was to scrutinize effects of some corticosteroids on glucose-6-phosphate dehydrogenase (G6PD) and some antioxidant enzymes. Initially, G6PD was purified from human erythrocytes by using ammonium sulphate precipitation and affinity chromatography. The two drugs, dexamethasone phosphate and prednisolone, investigated on the purified enzyme inhibited the enzyme activity. Comparative in vivo studies were performed to determine the effects of dexamethasone phosphate on the antioxidant enzyme activities using Spraque-Dawley rats. G6PD and catalase (CAT) activities were found significantly lower than in the control, whereas glutathione peroxidase (GP) activity was significantly increased in the erythrocytes of rats the receiving drug; glutathione reductase (GR) activity was unaffected. The results imply that dexamethasone phosphate may affect oxidative stress by changing antioxidant enzyme activities.

Suppression of steroidogenesis and activator protein-1 transcription factor activity in rat adrenals by vitamin E deficiency-induced chronic oxidative stress

Excessive oxidative stress and associated macromolecular damage are considered to be key features of aging, and appear to contribute to the age-related decline in steroid hormone production in adrenal and testicular Leydig cells. The current studies were initiated to examine the potential mechanism by which excessive oxidative stress during aging attenuates the functional expression of the oxidant-responsive transcription factor Activator protein-1. Chronic oxidative stress was induced in vivo by maintaining groups of rats on a diet deficient in vitamin E for 6 months. Plasma, liver, and adrenal tissues from vitamin E-deficient animals had negligible levels of this vitamin and showed high susceptibility to in vitro lipid peroxidation. Synthesis and secretion of corticosterone in response to corticotropin (ACTH), dibutyryl-cAMP, or 20alpha-hydroxycholesterol in vitro was significantly reduced in adrenocortical cells prepared cells from rats deficient in vitamin E. AP-1 DNA-binding activity was diminished approximately 55 % in adrenal extracts from vitamin E-deficient rats with no corresponding change in the binding activity of SP-1. The vitamin E deficiency-mediated loss of AP-1 activity was not due to an alteration in the dimeric composition of constituent proteins, but rather to a general down-regulation of steady-state levels of members of the Fos and Jun families of proteins. Interestingly, vitamin E deficiency also reduced the expression of the redox-regulated Ref-1 protein. Collectively these data demonstrate that chronic oxidative stress specifically down-regulates essential components of the AP-1 transcription factor complex, and suggest that aberrancies in AP-1 expression may adversely affect processes crucial for intracellular cholesterol transport and steroid hormone production.

Effects of Theanine on Alcohol Metabolism and Hepatic Toxicity

We previously showed that theanine, is a major amino acid in green tea, enhanced doxorubicin (DOX) induced antitumor activity. Besides, theanine induced the elevation of glutathione (GSH) level attributable to the increase of glutamate in the liver of mice, namely theanine would reduce the adverse reaction of DOX. Consequently, theanine was thought to be effective against the tissue changes with GSH level reduction. On the other hand, it is suggested excessive uptake of alcohol causes a production of free radicals, a decrease of GSH level, and an increase in the amount of lipid peroxide (LPO) in liver, and shifting to an alcoholic liver injury. Then, aiming at the prevention and medical treatment of a hepatic toxicity by the food components with little toxicity, we have studied the effect of theanine (i.p.) on ethanol metabolism and hepatic toxicity using ethanol (p.o.) single-administered mice. On the 1st hour after ethanol administration, the ethanol concentrations in blood of the theanine combined groups decreased compared with the ethanol-alone group. The alcohol dehydrogenase and aldehyde dehydrogenase activities in the liver increased by combined theanine. Since the elevation of cytochrome P450 (CYP) 2E1 activity was controlled in the theanine-combined groups, it was considered that these disorders attributable to CYP2E1 in ethanol long-term uptake might be avoidable by theanine. Although LPO increased in 3 h after by single-administration of ethanol, the increase was controlled by theanine-administration and was improved until the normal level. In conclusion, it was indicated that theanine was effective against alcoholic liver injury.

Effects of antiemetic drugs on glucose 6-phosphate dehydrogenase and some antioxidant enzymes

The aim of this study was to investigate effect of antiemetics on G6PD and antioxidant enzymes. Antiemetics are currently being used to reduce or prevent nausea and vomiting in patients. This is the first study to show effect of antiemetics on glucose-6-phosphate dehydrogenase (G6PD) and antioxidant enzyme activities. For in vitro studies, G6PD was purified from human erythrocyte, 10, 26-fold in a yield of 51.3% by using ammonium sulphate precipitation and 2',5'-ADP-Sepharose 4B affinity gel. The purified enzyme showed a single band on sodium dodecyl sulfate-polyacrilamide gel electrophoresis (SDS-PAGE). The effects of four different antiemetics (granisetron hydrochloride, ondansetron hydrochloride, metoclopramide hydrochloride, trimethobenzamide hydrochloride) were investigated on the purified enzyme. Granisetron hydrochloride and ondansetron hydrochloride inhibited the enzyme activity (Ki values; 5.05 mM and 0.034 mM, I50 values; 3.9 mM and 0.036 mM, respectively). Metoclopramide hydrochloride, trimethobenzamide hydrochloride showed no inhibition effects. In addition, in vivo studies, effects of ondansetron hydrochloride on the G6PD, glutathione reductase (GR), glutathione peroxidase (GPx) and catalase (CAT) were examined in the rat erythrocytes. G6PD (49% of control), GR (55% of control), CAT (60% of control) activities in erythrocytes were significantly decreased whereas GPx (183% of control) was significantly increased. A marked alteration in these enzymes may be result of oxidative stress in the rats receiving ondansetron hydrochloride.

Effects of anabolic steroids and antioxidant vitamins on ethanol-induced tissue injury

Various mechanisms are involved in the process of ethanol-induced tissue impairment. Oxidative stress and its effects are among the most important. We compared the effects of antioxidant vitamins (vitamin C and E in combination) and steroids (testosterone and nandrolone separately) on the toxicity of ethanol in rats. Animals (male Wistar rats, n = 48) were randomised into following groups-Control, Ethanol, Testosterone, Ethanol + Testosterone, Ethanol + Nandrolone, Ethanol + Vitamins. Alcohol was given daily by gavage in a dose of 5 g/kg of body weight. On the 27th day of the study the animals were sacrificed by decapitation and tissue samples were taken. Metabolic status, parameters of the hepatic metabolism, hormone levels (testosterone, ACTH, corticosterone), lipoperoxidation markers (malondialdehyde and conjugated diens in forebrain cortex and in cerebellum) and advanced glycation end-products were analysed. Tissue samples underwent histological examination. Histological outcomes showed a protective effect of antioxidants on hepatic and cerebellar injury caused by chronic ethanol intake. Anabolic steroids protected especially the central nervous tissue against the toxicity of alcohol. Both, antioxidant vitamins and anabolic steroids protect against the ethanol-induced toxicity, however, this effect is tissue specific.

Experimentally induced hypo- and hyper-thyroidism influence on the antioxidant defence system in adult rat testis

The objective of the present experiment was to study the effect of thyroid hormone on the antioxidant defence system of rat testis. Hypothyroidism induced in rats by 6-n propyl 2-thiouracil (PTU) treatment resulted in a reduction in body weight, seminal vesicle and ventral prostate gland. A further decrease in the weight of seminal vesicle was recorded following administration of T3 to hypothyroid rats. The oxidative stress parameters such as hydrogen peroxide and protein carbonyl content increased in the crude homogenate of testis of hypothyroid rats. T3 administration to hypothyroid rats resulted in no further change in the hydrogen peroxide level but the protein carbonyl content further elevated in the crude homogenate of testis. No significant change was observed in the endogenous lipid peroxidation level of the crude homogenate of testis whereas the FeSO4/ascorbic acid induced lipid peroxidation level decreased in hypothyroid rats and did not change further by T3 administration. Although the reduced glutathione level in the crude homogenate of testis did not change following hypothyroidism, oxidized glutathione level increased. The reduced and oxidized glutathione level decreased and increased, respectively following T3 administration to hypothyroid rats in comparison with PTU-treated rats. Activities of superoxide dismutase and catalase decreased in the post-mitochondrial fraction (PMF) of testis of hypothyroid rats. T3 injection to PTU-treated rats resulted in an elevation in the level of catalase activity only. The activity of glutathione peroxidase in the PMF of testis elevated in the hypothyroid rats and reduced following T3 treatment to hypothyroid rats. The results of the present study suggest that any alteration in the thyroid hormone level in the body affects the antioxidant defence system of testis of adult rats and, thereby, may affect the physiology of testis through oxidative stress.

Drinking beer reduces radiation-induced chromosome aberrations in human lymphocytes

We here investigated and reported the effects of beer drinking on radiation-induced chromosome aberrations in blood lymphocytes. Human blood that was collected either before or after drinking a 700 ml beer was in vitro irradiated with 200 kVp X rays or 50 keV/microm carbon ions. The relation between the radiation dose and the aberration frequencies (fragments and dicentrics) was significantly (p < 0.05) lower for lymphocytes collected 3 h after beer drinking than those before drinking. Fitting the dose response to a linear quadratic model showed that the alpha term of carbon ions was significantly (p < 0.05) decreased by beer drinking. A decrease of dicentric formation was detected as early as 0.5 h after beer drinking, and lasted not shorter than 4.5 h. The mitotic index of lymphocytes was higher after beer drinking than before, indicating that a division delay would not be responsible for the low aberrations induced by beer drinking. An in vitro treatment of normal lymphocytes with 0.1 M ethanol, which corresponded to a concentration of 6-times higher than the maximum ethanol concentration in the blood after beer drinking, reduced the dicentric formation caused by X-ray irradiation, but not by carbonion irradiation. The beer-induced reduction of dicentric formation was not affected by serum. It is concluded that beer could contain non-ethanol elements that reduce the chromosome damage of lymphocytes induced by high-LET radiation.

2-Bromopropane induces DNA damage, impairs functional antioxidant cellular defenses, and enhances the lipid peroxidation process in primary cultures of rat Leydig cells

Utilization of highly enriched preparations of steroidogenic Leydig cells has proven invaluable for studying the direct effects of various hormones and agents on Leydig cell function in vitro. It is widely reported that male reproductive organs are particularly susceptible to the deleterious effects of reactive oxygen species (ROS) and lipid peroxidation, which ultimately lead to impaired fertility. The purpose of the study was to examine the potential of 2-bromopropane (2-BP) to induce oxidative stress and antioxidant function in primary cultures of rat Leydig cells. Leydig cells were isolated from the testes of Sprague-Dawley rats. The purity of Leydig cells was determined to be 94.6% and the cells maintained their testosterone secreting capabilities for 48 h. Fresh medium containing 2-BP (1.00, 0.10, 0.01 mM, and vehicle control) and 1 U human chorionic gonadotropin (hCG) were added in the cell culture. Superoxide dismutase (SOD) activity, malondialdehyde (MDA), and glutathione peroxidase (GSH-PX) were analyzed in the medium of each well by biochemical methods. Additionally, DNA damage was examined using the Comet assay. The proportion of cells with undamaged DNA was decreased significantly and those with different grades of damaged DNA were increased significantly in the cells exposed to 2-BP. The level of MDA and GSH-PX activity increased significantly in the cell groups exposed to 0.10 and 1.00 mM 2-BP, whereas, SOD activity decreased considerably in these two groups of cells when compared to the control. The data indicate that 2-BP induces DNA damage, impairs functional antioxidant cellular defenses, and enhances the lipid peroxidation in cultured Leydig cells. These effects may be responsible for the testicular toxicity noted in laboratory animals and humans.