Oral or intraperitoneal binge drinking and oxidative balance in adolescent rats

Selenium supplementation via modulation of selenoproteins ameliorates binge drinking-induced oxidative, energetic, metabolic, and endocrine imbalance in adolescent rats' skeletal muscle

Adolescence is characterized by increased vulnerability to addiction and ethanol (EtOH) toxicity, particularly through binge drinking (BD), a favored acute EtOH-ingestion pattern among teenagers. BD, highly pro-oxidant, induces oxidative stress (OS), affecting skeletal muscle (SKM), where selenium (Se), an antioxidant element and catalytic center of selenoproteins, is stored, among other tissues. Investigating the effects of Se supplementation on SKM after BD exposure holds therapeutic promise. For this, we randomised 32 adolescent Wistar rats into 4 groups, exposed or not to intermittent i.p. BD [BD and control (C)] (3 g EtOH per kg per day), and supplemented with selenite [BDSe and CSe] (0.4 ppm). In SKM, we examined the oxidative balance, energy status (AMPK, SIRT-1), protein turnover (IRS-1, Akt1, mTOR, IGF-1, NF-κB p65, MAFbx, ULK1, pelF2α), serum myokines (myostatin, IL-6, FGF21, irisin, BDNF, IL-15, fractalkine, FSTL-1, FABP-3), and selenoproteins (GPx1, GPx4, SelM, SelP). In the pancreas, we studied the oxidative balance and SIRT-1 expression. Selenite supplementation mitigated BD-induced OS by enhancing the expression of selenoproteins, which restored oxidative balance, notably stimulating protein synthesis and normalizing the myokine profile, leading to improved SKM mass growth and metabolism, and reduced inflammation and apoptosis (caspase-3). Selenite restoration of SelP's receptor LRP1 expression, reduced by BD, outlines the crucial role of SKM in the SelP cycle, linking Se levels to SKM development. Furthermore, Se attenuated pancreatic OS, preserving insulin secretion. Se supplementation shows potential for alleviating SKM damage from BD, with additional beneficial endocrine effects on the pancreas, adipose tissue, liver, heart and brain that position it as a broad-spectrum treatment for adolescent alcohol consumption, preventing metabolic diseases in adulthood.

Treadmill Exercise Reshapes Cortical Astrocytic and Neuronal Activity to Improve Motor Learning Deficits Under Chronic Alcohol Exposure

Alcohol abuse induces various neurological disorders including motor learning deficits, possibly by affecting neuronal and astrocytic activity. Physical exercise is one effective approach to remediate synaptic loss and motor deficits as shown by our previous works. In this study, we unrevealed the role of exercise training in the recovery of cortical neuronal and astrocytic functions. Using a chronic alcohol injection mouse model, we found the hyperreactivity of astrocytes along with dendritic spine loss plus lower neuronal activity in the primary motor cortex. Persistent treadmill exercise training, on the other hand, improved neural spine formation and inhibited reactive astrocytes, alleviating motor learning deficits induced by alcohol exposure. These data collectively support the potency of endurance exercise in the rehabilitation of motor functions under alcohol abuse.

Folic acid antioxidant supplementation to binge drinking adolescent rats improves hydric-saline balance and blood pressure, but fails to increase renal NO availability and glomerular filtration rate

Binge drinking (BD) is an especially pro-oxidant pattern of alcohol consumption, particularly widespread in the adolescent population. In the kidneys, it affects the glomerular filtration rate (GFR), leading to high blood pressure. BD exposure also disrupts folic acid (FA) homeostasis and its antioxidant properties. The aim of this study is to test a FA supplementation as an effective therapy against the oxidative, nitrosative, and apoptotic damage as well as the renal function alteration occurred after BD in adolescence. Four groups of adolescent rats were used: control, BD (exposed to intraperitoneal alcohol), control FA-supplemented group and BD FA-supplemented group. Dietary FA content in control groups was 2 ppm, and 8 ppm in supplemented groups. BD provoked an oxidative imbalance in the kidneys by dysregulating antioxidant enzymes and increasing the enzyme NADPH oxidase 4 (NOX4), which led to an increase in caspase-9. BD also altered the renal nitrosative status affecting the expression of the three nitric oxide (NO) synthase (NOS) isoforms, leading to a decrease in NO levels. Functionally, BD produced a hydric-electrolytic imbalance, a low GFR and an increase in blood pressure. FA supplementation to BD adolescent rats improved the oxidative, nitrosative, and apoptotic balance, recovering the hydric-electrolytic equilibrium and blood pressure. However, neither NO levels nor GFR were recovered, showing in this study for the first time that NO availability in the kidneys plays a crucial role in GFR regulation that the antioxidant effects of FA cannot repair.

Adipose tissue homeostasis orchestrates the oxidative, energetic, metabolic and endocrine disruption induced by binge drinking in adolescent rats

Binge drinking (BD) is the most common alcohol consumption model for adolescents, and has recently been related to the generation of high oxidation and insulin resistance (IR). White adipose tissue (WAT) is a target organ for insulin action that regulates whole-body metabolism by secreting adipokines. The present study aimed to analyse the oxidative, inflammatory, energetic and endocrine profile in the WAT of BD-exposed adolescent rats, to obtain an integrative view of insulin secretion and WAT in IR progression. Two groups of male adolescent rats were used: control (n = 8) and BD (n = 8). An intermittent i.p. BD model (20% v/v) was used during 3 consecutive weeks. BD exposure led to a pancreatic oxidative imbalance, which was joint to high insulin secretion by augmenting deacetylase sirtuin-1 (SIRT-1) pancreatic expression and serum adipsin levels. However, BD rats had hyperglycaemia and high homeostasis model assessment of insulin resistance value (HOMA-IR). BD exposure in WAT increased lipid oxidation, as well as decreased insulin receptor substrate 1 (IRS-1) and AKT expression, sterol regulatory element-binding protein 1 (SREBP1), forkhead box O3A (FOXO3a) and peroxisome proliferator-activated receptor γ (PPARγ), and adipocyte size. BD also affected the expression of proteins related to energy balance, such as SIRT-1 and AMP activated protein kinase (AMPK), affecting the adipokine secretion profile (increasing resistin/adiponectin ratio). BD altered the entire serum lipid profile, increasing the concentration of free fatty acids. In conclusion, BD led to an oxidative imbalance and IR process in WAT, which modified the energy balance in this tissue, decreasing the WAT lipogenic/lipolytic ratio, affecting adipokine secretion and the systemic lipid profile, and contributing to the progression of IR. Therefore, WAT is key in the generation of metabolic and endocrine disruption after BD exposure during adolescence in rats. KEY POINTS: Adolescent rat binge drinking (BD) exposure leads to hepatic and systemic oxidative stress (OS) via reactive oxygen species generation, causing hepatic insulin resistance (IR) and altered energy metabolism. In the present study, BD exposure in adolescent rats induces OS in the pancreas, with increased insulin secretion despite hyperglycaemia, indicating a role for IR in white adipose tissue (WAT) homeostasis. In WAT, BD produces IR and an oxidative and energetic imbalance, triggering an intense lipolysis where the serum lipid profile is altered and free fatty acids are increased, consistent with liver lipid accumulation and steatosis. BD exposure heightens inflammation in WAT, elevating pro-inflammatory and reducing anti-inflammatory adipokines, favouring cardiovascular damage. This research provides a comprehensive view of how adolescent BD in rats impacts liver, WAT and pancreas homeostasis, posing a risk for future cardiometabolic complications in adulthood.

D-ribose-L-cysteine exhibits neuroprotective activity through inhibition of oxido-behavioral dysfunctions and modulated activities of neurotransmitters in the cerebellum of Juvenile mice exposed to ethanol

Alcohol exposure to the cerebellum has been known to trigger cerebellar dysfunctions through several mechanisms. This present study was designed to evaluate the repealing effect of D-ribose-L-cysteine (DRLC) on alcohol-induced cerebellar dysfunctions in juvenile BALB/c mice. The animals were randomly divided into 4 groups (n = 10 per group). Mice were given oral administration of normal saline (control), DRLC (100 mg/kg, p.o), ethanol (0.2 mL of 10% w/v), or DRLC (100 mg/kg, p.o) + ethanol (0.2 mL of 10% w/v). On day 29 of the study (i.e., 24 h after the administration of the last respective doses), neurochemical quantification of the respective levels of serotonin and dopamine, lipid peroxidation, total antioxidant, superoxide dismutase, and glutathione peroxidase in the cerebellar tissues of the mice were analyzed. Compared with the saline-treated group, the studied neurochemical indices were modulated across the various experimental groups. The administration of ethanol significantly modulates the levels of monoamine neurotransmitters (serotonin and dopamine) as well as contents of total antioxidants, activities of superoxide dismutase, and glutathione peroxidase, with a concurrently increased level of lipid peroxidase in the cerebellar tissue of the mice. DRLC significantly reverses these effects in the DRLC + ethanol co-treated group. Combined exposure to DRLC + ethanol counteracts the deleterious effect of ethanol in the cerebellum of juvenile BALB/c mice via monoamine neurotransmitter, lipid peroxidation, total antioxidant status, superoxide dismutase, and glutathione peroxidase action pathways. Therefore, DRLC could be a pharmacologic or therapeutic agent in attenuating the deleterious effects of alcohol on the cerebellum.

Binge drinking during the adolescence period causes oxidative damage-induced cardiometabolic disorders: A possible ameliorative approach with selenium supplementation

Binge drinking (BD) is the most common alcohol consumption model among adolescents. BD exposure during adolescence disrupts the nervous system function, being involved in the major mortality causes at this age: motor vehicle accidents, homicides and suicides. Recent studies have also shown that BD consumption during adolescence affects liver, renal and cardiovascular physiology, predisposing adolescents to future adult cardiometabolic damage. BD is a particularly pro-oxidant alcohol consumption pattern, because it leads to the production of a great source of reactive oxygen species (ROS) via the microsomal ethanol oxidizing system, also decreasing the antioxidant activity of glutathione peroxidase (GPx). Selenium (Se) is a mineral which plays a pivotal role against oxidation; it forms part of the catalytic center of different antioxidant selenoproteins such as GPxs (GPx1, GPx4, GPx3) and selenoprotein P (SelP). Specifically, GPx4 has an essential role in mitochondria, preventing their oxidation, apoptosis and NFkB-inflamative response, being this function even more relevant in heart's tissue. Se serum levels are decreased in acute and chronic alcoholic adult patients, being correlated to the severity of oxidation, liver damage and metabolic profile. Experimental studies have described that Se supplementation to alcohol exposed mice clearly decreases oxidative and liver damage. However, clinical BD effects on Se homeostasis and selenoproteins' tissue distribution related to oxidation during adolescence are not yet studied. In this narrative review we will describe the use of sodium selenite supplementation as an antioxidant therapy in adolescent BD rats in order to analyze Se homeostasis implication during BD exposure, oxidative balance, apoptosis and inflammation, mainly in liver, kidney, and heart. These biomolecular changes and the cardiovascular function will be analyzed. Se supplementation therapies could be a good strategy to prevent the oxidation, inflammation and apoptosis generated in tissues by BD during adolescence, such as liver, kidney and heart, improving cardiovascular functioning.

Folic Acid Homeostasis and Its Pathways Related to Hepatic Oxidation in Adolescent Rats Exposed to Binge Drinking

Chronic ethanol consumption and liver disease are intimately related to folic acid (FA) homeostasis. Despite the fact that FA decreases lipid oxidation, its mechanisms are not yet well elucidated. Lately, adolescents have been practising binge drinking (BD), consisting of the intake of a high amount of alcohol in a short time; this is a particularly pro-oxidant form of consumption. The aim of this study is to examine, for the first time, FA homeostasis in BD adolescent rats and its antioxidant properties in the liver. We used adolescent rats, including control rats and rats exposed to an intermittent intraperitoneal BD model, supplemented with or without FA. Renal FA reabsorption and renal FA deposits were increased in BD rats; hepatic deposits were decreased, and heart and serum levels remained unaffected. This depletion in the liver was accompanied by higher transaminase levels; an imbalance in the antioxidant endogenous enzymatic system; lipid and protein oxidation; a decrease in glutathione (GSH) levels; hyper-homocysteinemia (HHcy); an increase in NADPH oxidase (NOX) 1 and NOX4 enzymes; an increase in caspase 9 and 3; and a decrease in the anti-apoptotic metallopeptidase inhibitor 1. Furthermore, BD exposure increased the expression of uncoupled endothelial nitric oxide synthase (eNOS) by increasing reactive nitrogen species generation and the nitration of tyrosine proteins. When FA was administered, hepatic FA levels returned to normal levels; transaminase and lipid and protein oxidation also decreased. Its antioxidant activity was due, in part, to the modulation of superoxide dismutase activity, GSH synthesis and NOX1, NOX4 and caspase expression. FA reduced HHcy and increased the expression of coupled eNOS by increasing tetrahydrobiopterin expression, avoiding nitrosative stress. In conclusion, FA homeostasis and its antioxidant properties are affected in BD adolescent rats, making it clear that this vitamin plays an important role in the oxidative, nitrosative and apoptotic hepatic damage generated by acute ethanol exposure. For this, FA supplementation becomes a potential BD therapy for adolescents, preventing future acute alcohol-related harms.

Effects of binge drinking and the anti-inflammatory drug indomethacin on spatial memory and cognitive flexibility in mice

In previous research, we found that chronic-intermittent ethanol administration (CIEA), a model of binge drinking, impaired emotional memory in mice, and this impairment was counteracted by the anti-inflammatory drug indomethacin. In the present study, we evaluated the effects of CIEA on spatial memory and cognitive flexibility in adolescent mice of both sexes. Animals were randomly assigned to one of four groups for each sex: SS (saline + saline), SA (saline + alcohol), SI (saline + indomethacin), and AI (alcohol + indomethacin). They were injected with saline, ethanol (3 g/kg) or indomethacin (10 mg/kg) for the first three days of each week, throughout three weeks. 96 h after treatment, subjects learnt a standard water maze task on five consecutive days (4-day training and 1-day probe trial). One day later, mice underwent a reversal task for evaluating spatial cognitive flexibility. Animals receiving alcohol (SA and AI groups) did not differ from controls (SS groups) during the standard task, but animals treated with indomethacin performed better than controls, both in the acquisition trials and the probe trial. During the reversal task, no significant differences between alcohol groups and controls were observed, but the indomethacin group showed significant lower escape latencies than controls. No sex differences were found in either task. In conclusion, binge drinking does not impair spatial memory or spatial cognitive flexibility, while the anti-inflammatory indomethacin improves both, showing that the effects of alcohol and indomethacin on spatial memory (dependent on hippocampus) are different to those they exert on emotional memory (dependent on amygdala).

Selenium, a dietary-antioxidant with cardioprotective effects, prevents the impairments in heart rate and systolic blood pressure in adolescent rats exposed to binge drinking treatment

BACKGROUND

Binge drinking (BD) during adolescence is related to cardiovascular alterations. Selenium (Se) is an essential trace element with antioxidant, anti-inflammatory and antiapoptotic properties, essential for correct heart function.

OBJECTIVES

To study the protective cardiovascular effects of selenium in adolescent rats exposed to a BD-like procedure.

METHODS

32 adolescent male rats exposed to an intraperitoneally BD-like model or not, and supplemented with 0.4ppm of selenite or not, were divided into 4 groups: control, alcohol, control-selenium and alcohol-selenium. Blood pressure and heart rate (HR) were determined after experimentation. Se deposits, oxidative balance and the expression of glutathione peroxidases (GPxs), NF-kB and caspase-3 were measured in the heart. Also, DNA instability in rat lymphocytes and serum vascular markers were determined. Statistical analysis was performed with the ANOVA model.

RESULTS

The BD-like model depleted Se heart deposits (p < .01), decreased GPx activity (p < .01) and GPx1 (p < .001) and GPx4 (p < .05) expression, increased NF-kB (p < .01), caspase-3 (p < .001) expression, and generated oxidation in myocytes. Outside the heart, the BD-like model caused double-strand breaks in lymphocyte DNA and increased all the vascular markers measured. These cardiovascular alterations were related to higher systolic (p < .001) and diastolic (p < .05) blood pressure and HR (p < .05). In the heart, Se supplementation in BD-exposed rats significantly increased Se deposits (p < .001) and improved oxidative balance and vascular damage, including increased GPxs and decreased NF-kB and caspase-3 activation, consequently decreasing systolic (p < .05) blood pressure and HR (p < .01).

CONCLUSIONS

Se supplementation presents cardioprotective effects since it reversed HR and systolic blood pressure observed in BD-exposed adolescent rats.

Fetal Programming Is Deeply Related to Maternal Selenium Status and Oxidative Balance; Experimental Offspring Health Repercussions

Nutrients consumed by mothers during pregnancy and lactation can exert permanent effects upon infant developing tissues, which could represent an important risk factor for diseases during adulthood. One of the important nutrients that contributes to regulating the cell cycle and tissue development and functionality is the trace element selenium (Se). Maternal Se requirements increase during gestation and lactation. Se performs its biological action by forming part of 25 selenoproteins, most of which have antioxidant properties, such as glutathione peroxidases (GPxs) and selenoprotein P (SELENOP). These are also related to endocrine regulation, appetite, growth and energy homeostasis. In experimental studies, it has been found that low dietary maternal Se supply leads to an important oxidative disruption in dams and in their progeny. This oxidative stress deeply affects gestational parameters, and leads to intrauterine growth retardation and abnormal development of tissues, which is related to endocrine metabolic imbalance. Childhood pathologies related to oxidative stress during pregnancy and/or lactation, leading to metabolic programing disorders like fetal alcohol spectrum disorders (FASD), have been associated with a low maternal Se status and intrauterine growth retardation. In this context, Se supplementation therapy to alcoholic dams avoids growth retardation, hepatic oxidation and improves gestational and breastfeeding parameters in FASD pups. This review is focused on the important role that Se plays during intrauterine and breastfeeding development, in order to highlight it as a marker and/or a nutritional strategy to avoid diverse fetal programming disorders related to oxidative stress.

Selenite supplementation modulates the hepatic metabolic sensors AMPK and SIRT1 in binge drinking exposed adolescent rats by avoiding oxidative stress

Binge drinking (BD) is the main alcohol consumption pattern among teenagers. Recently, oxidative stress (OS) generated by BD exposure has been related to hepatic metabolic deregulation and cardiovascular dysfunction. This study analyzed if BD by generating oxidative stress modulates the alteration in hepatic energy homeostasis through two important regulators of energy metabolism: the NAD⁺-dependent sirtuin deacetylase (SIRT1) and AMP-activated protein kinase (AMPK) and if supplementation with the antioxidant selenium (Se) improves these metabolic disorders. Four groups of adolescent rats supplemented or not with Se (0.4 ppm) and exposed to intermittent i.p. BD were used. BD rats showed an increased AST/ALT ratio, total bilirubin in serum and lipid peroxidation in the liver. The BD rats also showed a higher abdominal/thoracic ratio and increased levels of TG, gluc, and chol compared to the control group, provoking an increase in mean blood pressure (MBP). This alcohol consumption pattern decreased hepatic Se deposits, cytoplasmic GPx activity, and GSH levels as well as the expressions of two metabolic sensors and the pAMPK/AMPK ratio. Se supplementation restored antioxidant parameters and decreased lipid oxidation, avoiding OS and improving the hepatic expression of pAMPK and SIRT1, contributing to the improvement of metabolic (better lipid profile and IRS-1 expression) and vascular function (lower MBP), and to the increase of hepatic functionality (lower AST/ALT ratio). All these actions decrease cardiometabolic risk factor development in the short and long term and could disrupt the relationship between BD and MS, two problems which are currently affecting adolescents.

An Animal Model of Alcohol Binge Drinking: Chronic-Intermittent Ethanol Administration in Rodents

Binge drinking (BD), characterized by intermittent consumption of large quantities of alcohol in short periods of time, is the main alcohol consumption pattern in adolescents and young adults. BD has serious biomedical consequences, and it is a prominent risk factor for later development of alcohol use disorders. Rodent models offer exceptional power to study these negative consequences of BD. This chapter focuses on one of these BD models: the chronic-intermittent ethanol administration (CIEA) paradigm. Essentially, CIEA consists of the administration in rats or mice of i.p. injections of ethanol (doses: 3-4 g/kg) for several consecutive days each week, in alternation with several days without injections, during several weeks. Due to our interest in the neurobehavioral effects of BD, a combination of the CIEA model with a battery of behavioral tests is described, with emphasis on the effects of alcohol BD on different kinds of memory. The CIEA model, in combination with behavioral tasks, seems to be a useful tool for studying the neurobehavioral effects of BD as well as for developing potential prevention and treatment strategies.

Emotional memory impairment produced by binge drinking in mice is counteracted by the anti-inflammatory indomethacin

The Binge Drinking (BD) pattern of alcohol consumption, prevalent in adolescents and young adults, has been associated with memory impairment. In addition, evidence shows that alcohol abuse causes neuroinflammation, which may contribute to the brain damage produced by alcohol and explain its cognitive consequences. In this study, we evaluated the effectiveness of the anti-inflammatory indomethacin in counteracting the memory impairment produced by alcohol (ethanol) in adolescent mice of both sexes. Animals were randomly assigned to one of four groups for each sex: SS (saline + saline), SA (saline + alcohol), SI (saline + indomethacin) and AI (alcohol + indomethacin). They were injected acutely (Experiment 1) or chronically intermittent (Experiment 2) with saline, ethanol (3 g/kg) and indomethacin (10 mg/kg). All subjects were evaluated in an inhibitory avoidance task 96 h after treatment. With acute administration, SA groups showed significantly lower Test latencies than SS groups, while AI groups had similar latencies to controls. The chronic-intermittent administration of alcohol, an animal model of BD, produced significant emotional memory impairment -blocking learning in males- which was counteracted by indomethacin, as the AI groups had similar latencies to the SS groups. No significant differences were observed in locomotor activity or analgesia. In conclusion, alcohol BD (one or several episodes) impairs emotional memory in mice. This impairment is not secondary to the effects of alcohol BD on locomotor activity or pain sensitivity, and it is counteracted by indomethacin. Therefore, the memory impairment produced by alcohol BD seems to be mediated, in part, by neuroinflammatory processes. These findings open a window for new treatments for alcohol use disorders.

Oxidative Stress Parameters in the Liver of Growing Male Rats Receiving Various Alcoholic Beverages

Typical alcohol consumption begins in the adolescence period, increasing the risk of alcoholic liver disease (ALD) in adolescents and young adults, and while the pathophysiology of ALD is still not completely understood, it is believed that oxidative stress may be the major contributor that initiates and promotes the progression of liver damage. The aim of the present study was to assess the influence of alcohol consumption on the markers of oxidative stress and liver inflammation in the animal model of prolonged alcohol consumption in adolescents using various alcoholic beverages. In a homogenic group of 24 male Wistar rats (4 groups—6 animals per group), since 30th day of life, in order to mimic the alcohol consumption since adolescence, animals received (1) no alcoholic beverage (control group), (2) ethanol solution, (3) red wine, or (4) beer (experimental groups) for 6 weeks. Afterwards, the activities of alcohol dehydrogenase (ADH), alanine aminotransferase (ALT), and aspartate aminotransferase (AST), as well as levels of cytochrome P450-2E1 (CYP2E1), thiobarbituric acid-reactive substances (TBARS), protein carbonyl groups, tumor necrosis factor-α (TNF-α), and interleukine-10 (IL-10) were measured in liver homogenates. The difference between studied groups was observed for CYP2E1 and protein carbonyl groups levels (increased levels for animals receiving beer compared with control group), as well as for ALT activity (decreased activity for animals receiving beer compared with other experimental groups) (p < 0.05). The results suggested that some components of beer, other than ethanol, are responsible for its influence on the markers of oxidative stress and liver inflammation observed in the animal model of prolonged alcohol consumption in adolescents. Taking this into account, beer consumption in adolescents, which is a serious public health issue, should be assessed in further studies to broaden the knowledge of the progression of liver damage caused by alcohol consumption in this group.

Understanding Addiction Using Animal Models

Drug addiction is a neuropsychiatric disorder with grave personal consequences that has an extraordinary global economic impact. Despite decades of research, the options available to treat addiction are often ineffective because our rudimentary understanding of drug-induced pathology in brain circuits and synaptic physiology inhibits the rational design of successful therapies. This understanding will arise first from animal models of addiction where experimentation at the level of circuits and molecular biology is possible. We will review the most common preclinical models of addictive behavior and discuss the advantages and disadvantages of each. This includes non-contingent models in which animals are passively exposed to rewarding substances, as well as widely used contingent models such as drug self-administration and relapse. For the latter, we elaborate on the different ways of mimicking craving and relapse, which include using acute stress, drug administration or exposure to cues and contexts previously paired with drug self-administration. We further describe paradigms where drug-taking is challenged by alternative rewards, such as appetitive foods or social interaction. In an attempt to better model the individual vulnerability to drug abuse that characterizes human addiction, the field has also established preclinical paradigms in which drug-induced behaviors are ranked by various criteria of drug use in the presence of negative consequences. Separation of more vulnerable animals according to these criteria, along with other innate predispositions including goal- or sign-tracking, sensation-seeking behavior or impulsivity, has established individual genetic susceptibilities to developing drug addiction and relapse vulnerability. We further examine current models of behavioral addictions such as gambling, a disorder included in the DSM-5, and exercise, mentioned in the DSM-5 but not included yet due to insufficient peer-reviewed evidence. Finally, after reviewing the face validity of the aforementioned models, we consider the most common standardized tests used by pharmaceutical companies to assess the addictive potential of a drug during clinical trials.

Cholinergic system and exploratory behavior are changed after weekly-binge ethanol exposure in zebrafish

Binge drinking is characterized by excessive alcohol consumption in a short period of time and is associated with a poor quality of life. Zebrafish are commonly used to investigate neurochemical, behavioral, and genetic parameters associated with ethanol (EtOH) exposure. However, few studies have used zebrafish as a model to investigate binge EtOH exposure. In order to elucidate the potential neurobehavioral impairments evoked by binge EtOH exposure in zebrafish, animals were immersed in 1.4% EtOH for 30 min three consecutive times with intervals of one week. Neurobehavioral parameters were analyzed immediately following the third exposure, as well as 2 and 9 days later. Brain choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) activities were reduced 9 days after the treatment. Thiobarbituric acid-reactive species and dichlorodihydrofluorescein levels were increased immediately after the treatment, but both returned to normal levels 2 days after the treatment. Catalase and glutathione reductase were impaired 2 and 9 days after the treatment. No alteration was observed in superoxide dismutase and glutathione peroxidase activities. EtOH treatment did not alter brain expression of inflammatory genes such as il-1β, il-10, and tnf-α. Zebrafish displayed anxiolytic-like behavior immediately after the last exposure, though there was no behavioral alteration observed 9 days after the treatment. Therefore, binge EtOH exposure in zebrafish leads to long lasting brain cholinergic alteration, probably related to oxidative stress immediately after the exposure, which is independent of classical inflammatory markers.

Influence of Alcohol Consumption on Body Mass Gain and Liver Antioxidant Defense in Adolescent Growing Male Rats

The World Health Organization (WHO) reported that alcohol consumption is a serious problem in adolescents. The aim of the study was to assess the influence of the time of exposure of various alcoholic beverages on body mass as well as on select parameters of liver antioxidant defense in adolescent Wistar rats. Thirty-day-old animals were divided into 12 groups (six animals in each): control and groups receiving various beverages containing 10% of alcohol (ethanol, red wine, beer), observed for two, four, and six weeks. The body weight gain and energy supply were analyzed for body mass assessment. The catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase, transferase (GST), reductase activities, total antioxidant status, and glutathione level (GSH) were analyzed, for a liver antioxidant defense assessment. Group receiving red wine was characterized by the highest alcohol intake, lowest dietary intake, and highest total energy supply (p < 0.05). However, this did not influence body weight gain (p > 0.05). Reduced diet intake in groups receiving alcohol was counterbalanced by its energy value. Therefore, the energy supply was not lower than for the control (p > 0.05). Alcohol consumption and the experiment duration influenced CAT, SOD, and GST activities and GSH level. Alcohol consumption may influence hepatic antioxidant defense in adolescent male rats, but without influence on body weight gain.

Ethanol-Induced Mitochondrial Damage in Sertoli Cells is Associated with Parkin Overexpression and Activation of Mitophagy

This study was conducted to elucidate the involvement of the PINK1-Parkin pathway in ethanol-induced mitophagy among Sertoli cells (SCs). In the research, adult rats were given intraperitoneal injections of ethanol (5 gm/kg) and sacrificed at various time periods within 24 h. Transmission electron microscopy was applied to reveal enhanced mitochondrial damage in SCs of the ethanol-treated rats (ETRs) in association with a significant increase in numbers of mitophagic vacuoles (mitophagosomes and autolysosomes) in contrast to very low levels in a control group treated with phosphate-buffered saline (PBS). This enhancement was ultra-structurally verified via observation of trapped mitochondria within LC3-labeled membranes, upregulation of LC3 protein levels, colocalization of LC3 and cytochrome c, and reduced expression of mitochondrial proteins. Importantly, Parkin expression was found to be upregulated in ETR SCs, specifically in mitochondria and mitophagosomes in addition to colocalization with PINK1 and pan-cathepsin, indicating augmented mitophagy. Transcription factor EB (TFEB, a transcription factor for autophagy and mitophagy proteins) was also found to be upregulated in nuclei of ETR SCs and associated with enhanced expression of iNOS. Enhanced Parkin-related mitophagy in ETR SCs may be a protective mechanism with therapeutic implications. To the authors’ knowledge, this is the first report demonstrating the ultrastructural characteristics and molecular mechanisms of Parkin-related mitophagy in ETR SCs.

On the Neurobiological Role of Oxidative Stress in Alcohol-Induced Impulsive, Aggressive and Suicidal Behavior

Objectives: Alcohol abuse is known to result in behavioral impairments (such as increased impulsivity, aggressive, and suicidal behavior), but the neurobiological basis for these behavioral impairments remains unknown. The objective of this review is to propose a neurobiological basis for alcohol-induced aggression, impulsivity, and suicidal behavior. Methods: Search was done by accessing PubMed/Medline, EBSCO, and PsycINFO databases. The search string used was "(Alcohol OR Alcoholism* OR Alcohol Abuse) AND (Behavior* OR Behavioral Impairment or Disorder) AND (Oxidative Stress OR Reactive Oxygen Species)." The electronic databases were searched for titles or abstracts containing these terms in all published articles between January 1, 1960, and May 31, 2019. The search was limited to studies published in English and other languages involving both animal and human subjects. Articles selected included randomized clinical trials (RCTs), observational studies, meta-analyses, and both systemic and narrative reviews, providing both quantitative and qualitative information with a measure of alcohol abuse or alcoholism as an outcome. Exclusion criteria were unpublished data of any form, including conference proceedings and dissertation. New key terms were identified (new term included: "Antioxidants, Neurotransmitters, Dopamine, Serotonin, GABA, Glutamate. Aggression, Impulsivity, Suicidal Behavior, hippocampus, prefrontal cortex, limbic system, psychiatric disorders, PTSD, Anxiety, Depression. These new terms were searched with Alcohol or Alcoholism or Alcohol Abuse and Oxidative Stress separately resulting in the identification of over 3000 articles. 196 were included in this article. Results: Multiple lines of evidence indicate that oxidative stress (OS) plays a critical underlying role in alcohol toxicity and behavioral impairments. Conclusions/Importance: People diagnosed with PTSD, anxiety disorder, depression, and those with a personality high in psychoticism as measured by the P Scale of the Eysenck Personality Questionnaire, with comorbid alcohol abuse or alcohol use disorder (AUD), may display increased impulsivity, aggression, and suicidal behavior because of the potentiating effect of alcohol-induced OS on their elevated brain oxidative status. Antioxidant therapy should be an integral part of acute alcohol intoxication and AUD treatment. Further research is necessary to fully understand the relationship between OS and alcohol-induced behavioral impairments.

Repeated Cycles of Binge-Like Ethanol Intake in Adolescent Female Rats Induce Motor Function Impairment and Oxidative Damage in Motor Cortex and Liver, but Not in Blood

Moderate ethanol consumption (MEC) is increasing among women. Alcohol exposure usually starts in adolescence and tends to continue until adulthood. We aimed to investigate MEC impacts during adolescence until young adulthood of female rats. Adolescent female Wistar rats received distilled water or ethanol (3 g/kg/day), in a 3 days on-4 days off paradigm (binge drinking) for 1 and 4 consecutive weeks. We evaluate liver and brain oxidative damage, peripheral oxidative parameters by SOD, catalase, thiol contents, and MDA, and behavioral motor function by open-field, pole, beam-walking, and rotarod tests. Our results revealed that repeated episodes of binge drinking during adolescence displayed lipid peroxidation in the liver and brain. Surprisingly, such oxidative damage was not detectable on blood. Besides, harmful histological effects were observed in the liver, associated to steatosis and loss of parenchymal architecture. In addition, ethanol intake elicited motor incoordination, bradykinesia, and reduced spontaneous exploratory behavior in female rats.

RNA interference against stromal interacting molecule-1 (STIM1) ameliorates ethanol-induced hepatotoxicity

Previously we have demonstrated that stromal interacting molecule-1 (STIM1) was involved in ethanol induced liver injury. However, the exact pathogenic mechanism of STIM1 in alcoholic liver disease (ALD) is still unknown. We constructed plasmid vectors encoding short-hairpin RNA against STIM1 to investigate its role in ALD in the rat liver cell line BRL and in Sprague-Dawley rats. The results showed that STIM1 targeted sh-RNA (Sh-STIM1) significantly ameliorated ethanol-induced BRL cells injury and liver injury in rats with 20 weeks-induced alcoholic liver disease. Inhibition of STIM1 also reduced intracellular calcium ion concentration, reactive oxygen species (ROS) production, lipid peroxidation, NF-kappa B activation and TNF-α production under ethanol exposure. STIM1 may play an important role in the pathogenesis of alcoholic liver disease. Silencing STIM1 may be effective in preventing alcoholic liver disease.

A Method for In Vivo Induction and Ultrastructural Detection of Mitophagy in Sertoli Cells

An emerging body of evidences based on in vitro studies indicate that mitophagy (selective autophagic clearance of damaged mitochondria) is a prosurvival mechanism, specifically under exposure to various stressors. Sertoli cells (SCs) play essential roles in maintenance of spermatogenesis via paracrine interactions with germ cells and other somatic cells in the testis; however, studies investigating mitophagy in SCs are still very few. In this chapter, we give a brief review of mechanisms and detection methods of mitophagy in SCs based on our recent publications on animal models of ethanol toxicity and current literature. In addition, we provide a method for induction and ultrastructural identification of mitophagy in SCs of adult Wistar rats using a single intraperitoneal injection (5 g/kg) of ethanol. Proper understanding of mitophagy features and mechanisms in SCs may have therapeutic implications for infertility associated with alcoholism and other diseases characterized by mitochondrial dysfunction.

Age-Dependent Effects of Acute Alcohol Administration in the Hippocampal Phosphoproteome

Alcohol consumption during adolescence is deleterious to the developing brain and leads to persistent deficits in adulthood. Several results provide strong evidence for ethanol-associated alterations in glutamatergic signaling and impaired synaptic plasticity in the hippocampus. Protein phosphorylation is a well-known and well-documented mechanism in memory processes, but information on phosphoprotein alterations in hippocampus after ethanol exposure is limited. This study focuses on age-related changes in the hippocampal phosphoproteome after acute alcohol administration. We have compared the phosphoprotein expression in the hippocampus of adult and adolescent Wistar rats treated with a single dose of ethanol (5 g/kg i.p.), using a proteomic approach including phosphoprotein enrichment by immobilized metal affinity chromatography (IMAC). Our proteomic analysis revealed that 13 proteins were differentially affected by age, ethanol administration, or both. Most of these proteins are involved in neuroprotection and are expressed less in young rats treated with ethanol. We conclude that acute alcohol induces important changes in the expression of phosphoproteins in the hippocampus that could increase the risk of neurodegenerative disorders, especially when the alcohol exposure begins in adolescence.

Voluntary alcohol intake after noise exposure in adolescent rats: Hippocampal-related behavioral alterations

Different physical or chemical agents, such as noise or alcohol, can induce diverse behavioral and biochemical alterations. Considering the high probability of young people to undergo consecutive or simultaneous exposures, the aim of the present work was to investigate in an animal model if noise exposure at early adolescence could induce hippocampal-related behavioral changes that might be modified after alcohol intake. Male Wistar rats (28-days-old) were exposed to noise (95-97 dB, 2 h). Afterwards, animals were allowed to voluntarily drink alcohol (10% ethanol in tap water) for three consecutive days, using the two-bottle free choice paradigm. After that, hippocampal-related memory and anxiety-like behavior tests were performed. Results show that whereas noise-exposed rats presented deficits in habituation memory, those who drank alcohol exhibited impairments in associative memory and anxiety-like behaviors. In contrast, exposure to noise followed by alcohol intake showed increases in exploratory and locomotor activities as well as in anxiety-like behaviors, unlike what was observed using each agent separately. Finally, lower levels of alcohol intake were measured in these animals when compared with those that drank alcohol and were not exposed to noise. Present findings demonstrate that exposure to physical and chemical challenges during early adolescence might induce behavioral alterations that could differ depending on the schedule used, suggesting a high vulnerability of rat developing brain to these socially relevant agents.

Folate deficiency in patients seeking treatment of alcohol use disorder

INTRODUCTION

Nutritional deficiency is frequent in patients with an alcohol use disorder (AUD). We aimed to analyze serum and erythrocyte folate deficiency in a case series of patients that initiated treatment of AUD.

PATIENTS AND METHODS

A cross-sectional study in patients admitted for detoxification between 2007 and 2015 was performed. Sociodemographic characteristics, history of alcohol consumption, type of alcohol, and medical co-morbidity were assessed at admission. Blood samples for biochemistry and hematological parameters were collected at admission. Logistic regression models were used to establish predictors of folate deficiency.

RESULTS

211 patients (79.1% men) were eligible; age at admission was 46 years [IQR:40-51], and the amount of alcohol consumption was of 160g/day [IQR:120-200]. Thirty four percent of patients had macrocytosis (MCV>100fL), 12.8% had anemia, 23% of cases presented with serum folate deficiency and 7% presented with erythrocyte folate deficiency. Most (69%) of the patients with serum folate deficiency had normal erythrocyte folate levels. In univariate analysis, macrocytosis (OR=3.4, 95%CI:1.7-6.6), alcohol-related liver disease (ARLD) (OR=2.5, 95%CI:1.0-6.1) and drinking alcoholic beverages other than beer (OR=3.3, 95%CI:1.5-7.3) were associated with folate deficiency. However, only macrocytosis was significantly associated with serum folate deficiency in multivariate analysis (OR=3.1, 95%CI:1.1-8.9). Macrocytosis (P<0.001), ARLD (P=0.01) and the type of alcohol consumption (P<0.001) were factors associated with erythrocyte folate deficiency in univariate analysis. In multivariate analysis only macrocytosis remained significantly associated to erythrocyte folate deficiency (P=0.037).

CONCLUSION

Folate deficiency is a relatively frequent finding in contemporary, middle-aged patients with AUD, and macrocytosis is significantly associated with the deficiency.

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

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 0.4ppm 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.

Upregulated Autophagy in Sertoli Cells of Ethanol-Treated Rats Is Associated with Induction of Inducible Nitric Oxide Synthase (iNOS), Androgen Receptor Suppression and Germ Cell Apoptosis

This study was conducted to investigate the autophagic response of Sertoli cells (SCs) to acute ethanol toxicity using in vivo and in vitro models. Adult Wistar rats were intraperitoneally injected with either 5 g/kg ethanol or phosphate-buffered saline (for the control group) and sacrificed 0, 3, 6 and 24 h after injection. Compared to the control group, enhanced germ cell apoptosis was observed in the ethanol-treated rats (ETRs) in association with upregulation of iNOS and reduced expression of androgen receptor protein levels in SCs, which were resistant to apoptosis. Meanwhile, autophagy was upregulated in ETR SCs (peaking at 24 h) compared to the control group, as evidenced by transcription factor EB (TFEB) nuclear translocation, enhanced expression of microtubule-associated protein 1 light chain3-II (LC3-II), lysosome-associated membrane protein-2 (LAMP-2), pan cathepsin protein levels and reduced expression of p62. This upregulation of SC autophagy was confirmed ultrastructurally by enhanced formation of autophagic vacuoles and by immunofluorescent double labelling of autophagosomal and lysosomal markers. Study of cultured SCs confirmed enhanced autophagic response to ethanol toxicity, which was cytoprotective based on decreased viability of SCs upon blocking autophagy with 3-methyladenine (3-MA). The results highlighted the molecular mechanisms of prosurvival autophagy in ETR SCs for the first time, and may have significant implications for male fertility.

The Differential Effects of Alcohol and Nicotine-Specific Nitrosamine Ketone on White Matter Ultrastructure

Aims

The chronic consumption of alcohol is known to result in neurodegeneration and impairment of cognitive function. Pathological and neuroimaging studies have confirmed that brain atrophy in alcoholics is mainly due to widespread white matter (WM) loss with neuronal loss restricted to specific regions, such as the prefrontal cortex. Neuroimaging studies of cigarette smokers also suggest that chronic inhalation of tobacco smoke leads to brain atrophy, although the neurotoxic component is unknown. As a high proportion of chronic alcoholics also smoke cigarettes it has been hypothesized that at least some alcohol-related brain damage is due to tobacco smoke exposure.

Methods

39 Long Evans rats were subjected to 8 weeks exposure to alcohol and/or 5 weeks co-exposure to nicotine-specific nitrosamine ketone (NNK), a proxy for tobacco smoke. Their frontal WM was then assayed with transmission electron microscopy.

Results

NNK and ethanol co-exposure had a synergistic effect in decreasing myelinated fibre density. Furthermore, NNK treatment led to a greater reduction in myelin sheath thickness than ethanol whereas only the ethanol-treated animals showed a decrease in unmyelinated fibre density.

Conclusion

These data suggest that NNK causes WM degeneration, an effect that is exacerbated by alcohol, but unlike alcohol, it has little impact on the neuronal components of the brain.

Triggering of Parkin Mitochondrial Translocation in Mitophagy: Implications for Liver Diseases

A growing body of evidence based on in vitro studies indicates that mitophagy (selective autophagic clearance of damaged mitochondria) is a prosurvival mechanism associated with cellular exposure to various mitochondrial stressors. Very recently, a limited number of publications on animal-based models of alcoholic fatty liver diseases have reported that Parkin-mediated mitophagy may mitigate hepatocyte apoptosis, improve mitochondrial quality and suppress steatosis (lipid accumulation). From this perspective, the authors focus on the mechanisms of Parkin mitochondrial translocation (a key consideration in mitophagy activation) and therapeutic implications of mitophagy in liver disease. DNA repair and other functions of Parkin beyond mitophagy are also briefly discussed. The paper additionally shows original data from the authors' current research indicating enhanced hepatic mitophagy in ethanol-treated rats, which is associated with Parkin mitochondrial translocation triggered by oxidative mitochondrial DNA damage. Natural or pharmaceutical products that may trigger Parkin mitochondrial translocation in hepatocytes and/or suppress repressors of such translocation could be a potential therapeutic target in alcoholic and non-alcoholic fatty liver disease.

Binge ethanol exposure increases the Krüppel-like factor 11-monoamine oxidase (MAO) pathway in rats: Examining the use of MAO inhibitors to prevent ethanol-induced brain injury

Binge drinking induces several neurotoxic consequences including oxidative stress and neurodegeneration. Because of these effects, drugs which prevent ethanol-induced damage to the brain may be clinically beneficial. In this study, we investigated the ethanol-mediated KLF11-MAO cell death cascade in the frontal cortex of Sprague-Dawley rats exposed to a modified Majchowicz 4-day binge ethanol model and control rats. Moreover, MAO inhibitors (MAOIs) were investigated for neuroprotective activity against binge ethanol. Binge ethanol-treated rats demonstrated a significant increase in KLF11, both MAO isoforms, protein oxidation and caspase-3, as well as a reduction in BDNF expression in the frontal cortex compared to control rats. MAOIs prevented these binge ethanol-induced changes, suggesting a neuroprotective benefit. Neither binge ethanol nor MAOI treatment significantly affected protein expression levels of the oxidative stress enzymes, SOD2 or catalase. Furthermore, ethanol-induced antinociception was enhanced following exposure to the 4-day ethanol binge. These results demonstrate that the KLF11-MAO pathway is activated by binge ethanol exposure and MAOIs are neuroprotective by preventing the binge ethanol-induced changes associated with this cell death cascade. This study supports KLF11-MAO as a mechanism of ethanol-induced neurotoxicity and cell death that could be targeted with MAOI drug therapy to alleviate alcohol-related brain injury. Further examination of MAOIs to reduce alcohol use disorder-related brain injury could provide pivotal insight to future pharmacotherapeutic opportunities.

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.

Binge drinking during adolescence disrupts Se homeostasis and its main hepatic selenoprotein expression

BACKGROUND

Binge drinking (BD) is the most common ethanol (EtOH) intake consumption model among teenagers, but little is known about its effects on the liver. During its hepatic metabolism, acute alcohol exposure produces a great amount of reactive oxygen species which contributes to alcohol-induced liver injury. Selenium (Se) plays a key role in antioxidant defense as it forms part of selenoproteins, such as the antioxidant glutathione peroxidases (GPxs) or the selenoprotein P (SelP), synthesized mainly in liver. Chronic EtOH consumption decreases both Se deposits and this tissue's antioxidant activity.

METHODS

Two BD administration routes (oral and intraperitoneal) were used in adolescent rats to analyze Se homeostasis; the main hepatic selenoproteins' expression: GPx1, GPx4, and SelP, and their biological roles related to oxidation. Their relationship with inflammatory processes was also determined by analyzing the expression of the transcriptional factor nuclear factor-kappa beta (NF-κB).

RESULTS

It has been demonstrated for the first time that BD in adolescents alters Se homeostasis regardless of the administration route employed, despite the fact that the BD oral group ingested less Se in diet. This decrease of Se in serum and liver is directly related to a decrease in serum GPx3 and hepatic GPx1 activity, contributing to the oxidative imbalance found. The depletion of Se detected in liver affects GPx1 expression and, surprisingly, GPx4 expression. This could be related to the lower expression of the transcriptional factor NF-κB in the liver, a key player in the regulation of inflammatory processes.

CONCLUSIONS

Due to the above, and to find whether a Se supplementation therapy improves these situations, it would be interesting to explore in more depth the relationship between Se, the high oxidation found, and the depressed immune response reported in BD adolescents.