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Dietary selenium plus folic acid as an antioxidant therapy for ethanol-exposed pups.

BACKGROUND Nutrients such as folic acid and selenium are decreased in dams exposed to ethanol during gestation and lactation, affecting their metabolism, antioxidant balance, and the future health of their progeny. We will study whether the supplementation of the maternal diet with folate and selenium can prevent ethanol-induced oxidative liver disorders in the offspring. METHODS Dams were randomised into four groups: control, alcohol, alcohol+folic acid+Se, and control+folic acid+Se. We determined selenium by graphite-furnace atomic absorption and antioxidant enzyme activities, lipid peroxidation, and protein carbonyl by spectrophotometry in the offspring. RESULTS Alcohol increased serum Se levels and glutathione peroxidase (GPx) activity. However, in the liver of pups from ethanol-exposed dams a decrease in selenium was provoked and GPx activity increased with the double supplementation. Glutathione reductase (GR) and catalase (CAT) activities increased with ethanol, while double supplementation significantly decreased the GR activity. The supplemented diet reduced the protein peroxidation found in ethanol pups. CONCLUSIONS These results suggest that folic acid+Se could be effective in neutralising the damage of ethanol consumption in pups since it prevents peroxidation protein products.

Alcohol, Gestation and Breastfeeding: Selenium as an Antioxidant Therapy

AIM The aim of this paper is to study the relationship between alcohol, selenium and oxidative stress in breastfeeding rat pups exposed to ethanol during gestation and lactation. We have also studied how a Se-supplemented diet among mothers could prevent different oxidative liver disorders in the pups. METHOD Pups of 21 days were randomized into four groups: control group (C), alcohol group (A), alcohol selenium group (AS) and control selenium group (CS). Alcohol was supplied to their mothers for 13 weeks (induction, reproduction, gestation and lactation periods). The selenium-supplemented diet contained 0.5 ppm as selenite. We determined serum and liver selenium by graphite-furnace atomic absorption spectrometry. We measured antioxidant enzyme activities: glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT) and superoxide dismutase (SOD); and lipid peroxidation (TBARS) and protein carbonyl (PC) by a spectrophotometric method in the liver. RESULTS In the liver of pups, exposure to ethanol provoked a decrease in selenium and GPx activity and an increase in GR and CAT activity, as well as in carbonyl groups in protein. A pups had higher Se levels and GPx activity in serum than C pups. Administering Se with alcohol balances the activities of scavenging enzymes and reduces peroxidation protein products. CONCLUSION These results suggest that selenium could be effective in neutralizing the damage of ethanol consumption during gestation and lactation in pups since it repairs selenium levels in liver as well as the activity of scavenging enzymes and peroxidation protein products. In serum, Se also recovers GPx activity and increases the levels of Se that are available to other organs.

Role of selenium and glutathione peroxidase on development, growth and oxidative balance in rat offspring.

Selenium (Se), an essential trace metal, is important in both growth and reproduction and is the constituent of different selenoproteins. The glutathione peroxidase (GPx) family is the most studied as it prevents oxidative stress. Liver oxidation is considered as another mechanism involved in low birth weight. Therefore, in order to ascertain whether GPx is related to the effects of Se on growth during gestation and lactation, three groups of rat pups were used: control, Se deficient (SD), and Se supplemented (SS). Morphological parameters and reproductive indices were evaluated. Hepatic Se levels were measured by graphite furnace atomic absorption while spectrophotometry was used for activity of antioxidant enzymes and oxidative stress markers in liver and western blotting for expression of hepatic GPx1 and GPx4. The SD diet increased mortality at birth; decreased viability and survival indices; and stunted growth, length, and liver development in offspring, thus decreasing hepatic Se levels, GPx, glutathione reductase, and catalase activities, while increasing superoxide dismutase activity and protein oxidation. The SS diet counteracted all the above results. GPx1 expression was heavily regulated by Se dietary intake; however, although Se dietary deficiency reduced GPx4 expression, this decrease was not as pronounced. Therefore, it can be concluded that Se dietary intake is intimately related to growth, length, and directly regulating GPx activity primarily via GPx1 and secondly to GPx4, thus affecting liver oxidation and development. These results suggest that if risk of uterine growth retardation is suspected, or if a neonate with low birth weight presents with signs of liver oxidation, it may be beneficial to know about Se status.

Ethanol Consumption by Wistar Rat Dams Affects Selenium Bioavailability and Antioxidant Balance in Their Progeny

Ethanol consumption affects maternal nutrition, the mothers’ antioxidant balance and the future health of their progeny. Selenium (Se) is a trace element cofactor of the enzyme glutathione peroxidase (GPx). We will study the effect of ethanol on Se bioavailability in dams and in their progeny. We have used three experimental groups of dams: control, chronic ethanol and pair-fed; and three groups of pups. Se levels were measured by graphite-furnace atomic absorption spectrometry. Serum and hepatic GPx activity was determined by spectrometry. We have concluded that ethanol decreased Se retention in dams, affecting their tissue Se deposits and those of their offspring, while also compromising their progeny’s weight and oxidation balance. These effects of ethanol are caused by a reduction in Se intake and a direct alcohol-generated oxidation action.

Oral or intraperitoneal binge drinking and oxidative balance in adolescent rats.

Oxidative imbalance is one of the most important mechanisms of alcohol-induced injury. Acute alcohol exposure induces a significant amount of reactive oxygen species during its hepatic metabolism via the microsomal ethanol oxidizing system. During adolescence, the physiological development is still taking place; therefore, ethanols effects differ in adolescents compared to that in adults. Because binge drinking is the most important model of ethanol intake used by adolescents and because little is known about its effects on the liver, we have used two routes of acute ethanol administration (oral and intraperitoneal) in adolescent rats in order to analyze the oxidative damage caused in the periphery and liver. Here, it has been demonstrated for the first time that binge drinking in adolescents causes peripheral oxidation of lipid and DNA as well as lipid and protein hepatic oxidation, which are related to lower glutathione peroxidise (GPx) activity, higher catalase (CAT) activity, and higher expression of NADPHoxidase, contributing to hepatic damage. In addition, it is shown that the intraperitoneal administration route results in increased oxidative damage, which is probably related to the resulting general stress response that causes higher DNA and protein oxidation due to higher NADPHoxidase expression and higher CAT and superoxide dismutase (SOD) activities. According to these results, it is concluded that binge drinking induces hepatic damage during adolescence, at least in part, as consequence of oxidative stress because the antioxidant response was insufficient to avoid liver oxidation. Alcohol administered intraperitoneally provoked more DNA oxidation than that from the oral alcohol exposure model.

Oxidative effects of chronic ethanol consumption on the functions of heart and kidney: folic acid supplementation.

AIMS The principal aim of this study was to investigate the oxidative effects of chronic ethanol consumption on the functions of the heart and the kidney and the possible modification of this effect by folic acid supplementation. Moreover, in order to find whether this oxidative profile affects cardiovascular function, parameters such as heart rate and glomerular filtration rate were also assessed. METHODS Four experimental groups of rats were used: control, ethanol-exposed, control supplemented with folic acid and ethanol-exposed plus folic acid. Ethanol-exposed rats were subjected to a chronic ethanol treatment (2 months), in which the level of alcohol reaches 30% v/v. Diet and ethanol solution were provided ad libitum, and folic acid supplementation was 8 vs. 2 ppm. Energy intake, creatinine clearance and heart rate were determined. Antioxidant enzyme activity and lipid and protein peroxidation of the kidney and the heart were measured by the spectrophotometric method. RESULTS Ethanol increases heart size and catalase (CAT) activity and decreases lipid peroxidation in heart without changing heart rate. However, in the kidney, ethanol decreases CAT activity, increases lipid peroxidation and decreases glomerular filtration rate. Folic acid supplementation avoids these situations; it does not, however, improve glomerular function. CONCLUSION Chronic ethanol consumption has many effects on the antioxidant enzymatic activity of the heart and the kidney, leading to increased renal lipid peroxidation prevented by folic acid supplementation.

Selenium Dietary Supplementation and Oxidative Balance in Alcoholism

Alcohol consumption causes major health and addiction problems that are the consequence of toxic compounds produced primarily by its oxidative metabolism at a hepatic level. The liver, therefore, is the main tissue exposed to this drug, but other tissues are also affected. Selenium (Se) is an essential trace mineral, fundamental to health because it presents antioxidant properties, and forms part of selenoproteins, such as glutathione peroxidase. Alcohol intake decreases Se deposits in the organism, as well as selenoproteins’ expressions and activity, exacerbating the problems induced by alcoholism. The aim of this chapter is to collect relevant information and data to support evidence on ethanol consumption and Se absorption and bioavailability in the organism, as well as its relationship with selenoproteins and oxidative stress. The role of dietary Se supplementation, as a means of acting against the adverse effects provoked by alcohol, emphasizing its action on oxidative balance, is also analyzed.

The Benefits of Administering Folic Acid in Order to Combat the Oxidative Damage Caused by Binge Drinking in Adolescent Rats

AIMS An important mechanism in alcohol-induced injury is biomolecular oxidative damage. Folic acid is supplied to chronic alcoholic patients in order to prevent this situation, as this is the main vitamin deficiency that they suffer from. Acute alcohol exposure, such as binge drinking, is one of the most widespread ethanol consumption models practiced by adolescents. However, there is no evidence of folic acid body profiles after this pattern of consumption. METHODS Four groups of adolescent rats were used: control, alcohol (exposed to intraperitoneal binge drinking), control folic acid-supplemented group and alcohol folic acid-supplemented group. Folic acid levels, protein, lipid and DNA oxidative damage in serum, and liver glutathione (GSH) and reduced/oxidized glutathione ratio (GSH/GSSG) were measured. RESULTS Binge-drinking rats had higher lipids and DNA oxidation levels. They also had lower hepatic GSH levels and GSH/GSSG ratio. Folic acid supplementation to binge-drinking rats does not change the serum protein oxidation but decreases lipid and DNA oxidation. Finally, GSH increased to control levels with folic acid supplementation. CONCLUSION Folic acid supplementation is an economic and efficient therapy against the oxidative damage in lipids and mainly in DNA stability caused by binge drinking during adolescence. It has also been demonstrated that folic acid increases GSH levels, improving the antioxidant status and revealing a hepatoprotective effect during binge drinking.

The effects of ethanol upon hydric balance and arterial pressure in rats: folic acid as a possible hypotensor.

AIMS Chronic alcohol intake is related to hypertension. There are, however, few studies concerning the effect of ethanol upon hydric balance in relation to arterial pressure. Folic acid intake has beneficial effects upon the cardiovascular system decreasing hyperhomocysteinemia, however, more studies imply that it is related with other mechanisms. Therefore, we have studied the effects of chronic alcohol intake (30% v/v) upon hydric-saline balance and hypertension and have found that dietary supplementation with folic acid (8 mg/kg) improves the above parameters. MAIN METHODS Our study used four experimental groups of rats: control, alcohol, alcohol with folic acid and control with folic acid. In all cases we measured the clearance of Na(+), K(+) and aldosterone; osmolarity in urine, liquid and solid ingestion; homocysteine levels in serum; cardiac frequency and arterial blood pressure. KEY FINDINGS The alcohol intake increases serum aldosterone and homocysteine, which is reflected in an increase in arterial blood pressure. In addition, we have found that alcohol intake reduces both liquid and solid ingestion (causing a malnourishment status), the clearance of creatinine, aldosterone, Na(+) and K(+), and the ratio ClNa(+)/ClCr; it also increases urine osmolarity. Folic acid supplementation increases the clearance of Na(+) and the ratio ClNa(+)/ClCr. SIGNIFICANCE Folic acid intake improves the hypertension provoked by alcohol by increasing the aldosterone clearance, drastically reducing the serum levels of this hormone and thus its hypertensor effect.

Biological implications of selenium in adolescent rats exposed to binge drinking: Oxidative, immunologic and apoptotic balance

&NA; Alcohol intermittent binge drinking (BD) during adolescence decreases the levels of selenium (Se), a trace element that plays a key biological role against oxidative damage in hepatocytes through different selenoproteins such as the antioxidant enzymes glutathione peroxidases (GPx1 and Gpx4) and selenoprotein P (SelP). In this context, it has been found that GPx4 has an essential antioxidant role in mitochondria modulating the apoptosis and NF‐kB activation (a factor intimately related to apoptosis and immune function). To further investigate the effectiveness of selenium supplementation in oxidative balance, inflammation and apoptosis, the present study examined the protective effects of 0.4 ppm of dietary selenite administrated to adolescent rats exposed to BD. BD consumption depleted Se deposits in all the tissues studied. In liver, GPx1 activity and expression were decreased leading to protein and lipid hepatic oxidation. Moreover GPx4 and NF‐kB expression were also decreased in liver, coinciding with an increase in caspase‐3 expression. This hepatic profile caused general liver damage as shown the increased serum transaminases ratio AST/ALT. Proinflammatory serum citokines and chemocines were decreased. Se supplementation therapy used restored all these values, even AST levels. These findings suggest for first time that Se supplementation is a good strategy against BD liver damage during adolescence, since it increases GPx1 and GPx4 expression and avoids NF‐kB downregulation and caspase‐3 upregulation, leading to a better oxidative, inflammatory and apoptotic liver profile. The therapy proposed could be considered to have a great biological efficacy and to be suitable for BD exposed teenagers in order to avoid future hepatic complications. HighlightsBinge drinking exposition increases ratio AST/ALT and caspase‐3 expression.Binge drinking also decreases citokines, chemocines and GPx4 and NF‐kB expression.Se supplementation therapy improves oxidative, inflammatory and apoptotic liver profile.The therapy proposed could suitable in BD exposition to avoid hepatic complications.