Jana Trebatická

Oxidative Stress in University Students during Examinations

Mental stress in psychiatric disease and in daily life contributes to oxidative stress in the body. In this study we investigated a connection between possible psychological stress caused by university undergraduate examinations and oxidative stress experienced by our test subjects. Some parameters of oxidative stress (single strand breaks of DNA in lymphocytes, sensitivity to lipid oxidation and antioxidant status) were studied in medical students on the day of the examination (stress condition) and compared with the same parameters obtained from the same students during the term between two examination periods (non-stress condition). The results show that in the stress condition oxidative damage to DNA and sensitivity to lipid oxidation were significantly increased (p<0.05) when compared with the same parameters in “non-stress” conditions. A significant decrease in plasma antioxidant activity (p<0.05) in students that were under stress was observed. These results suggest that during university examinations students are under increased oxidative stress.

Effect of polyphenolic extract, Pycnogenol®, on the level of 8-oxoguanine in children suffering from attention deficit/hyperactivity disorder

The purpose of this randomized, double-blind and placebo controlled study was to test the effect of polyphenolic extract of pine bark Pycnogenol® (Pyc) on the level of oxidized purines represented by 8-oxo-7,8-dihydroguanine (8-oxoG) and on the total antioxidant status (TAS) in children with attention deficit/hyperactivity disorder (ADHD). We have found significantly increased damage to DNA in ADHD children when compared to controls. 8-oxoG was significantly lower after 1 month of Pyc administration in comparison to the beginning state and to placebo group. TAS in ADHD children was lower in comparison to controls. After Pyc administration, TAS was elevated but statistically significant increase was recorded after 1 month of termination of Pyc application. Improvement of DNA damage and TAS after Pyc administration is associated with the improvement of attention in ADHD children. In conclusion, Pycnogenol® administration reduces oxidative damage to DNA, normalizes TAS and improves attention of ADHD children. Explanation of mutual relation between oxidative damage to DNA, TAS and symptoms of ADHD and mechanism of Pycs action needs further investigations.

Urinary catecholamines in children with attention deficit hyperactivity disorder (ADHD): Modulation by a polyphenolic extract from pine bark (Pycnogenol®)

Abstract Our study tested the hypothesis that treatment with a potent polyphenol complex not only reduces hyperactivity of children, but also catecholamine excretion and oxidative stress. Urine catecholamine concentrations were measured in attention deficit hyperactivity disorder (ADHD) children and healthy controls. ADHD children received either placebo (PL) or Pycnogenol® (Pyc), a bioflavonoid extract from the pine bark, for one month. The study was performed in a randomized, double-blind, PL controlled design. Concentrations of catecholamines were higher in urine of ADHD patients compared to those of healthy children. Moreover, noradrenaline (NA) concentrations positively correlated with degree of hyperactivity of ADHD children. In ADHD patients, adrenaline (A) and NA concentrations positively correlated with plasma levels of oxidized glutathione. The treatment of ADHD children with Pyc caused decrease of dopamine (D) and trend of A and NA decrase and increased GSH/GSSG ratio. In conclusion, the data provide further evidence for the overactivity of the noradrenergic system in ADHD and demonstrate that A release may be increased, as well. Treatment of ADHD children with Pyc normalized catecholamine concentrations, leading to less hyperactivity, and, consequently, to reduced oxidative stress.

Markers of Oxidative Stress and Neuroprogression in Depression Disorder

Major depression is multifactorial disorder with high prevalence and alarming prognostic in the nearest 15 years. Several mechanisms of depression are known. Neurotransmitters imbalance and imbalance between neuroprogressive and neuroprotective factors are observed in major depression. Depression is accompanied by inflammatory responses of the organism and consequent elevation of proinflammatory cytokines and increased lipid peroxidation are described in literature. Neuropsychiatric disorders including major depression are also associated with telomerase shortening, oxidative changes in nucleotides, and polymorphisms in several genes connected to metabolism of reactive oxygen species. Mitochondrion dysfunction is directly associated with increasing levels of oxidative stress. Oxidative stress plays significant role in pathophysiology of major depression via actions of free radicals, nonradical molecules, and reactive oxygen and nitrogen species. Products of oxidative stress represent important parameters for measuring and predicting of depression status as well as for determining effectiveness of administrated antidepressants. Positive effect of micronutrients, vitamins, and antioxidants in depression treatment is also reviewed.

The effect of polyphenolic extract from pine bark, Pycnogenol® on the level of glutathione in children suffering from attention deficit hyperactivity disorder (ADHD)

Abstract Attention deficit hyperactivity disorder (ADHD) belongs to the neurodevelopmental disorders characterized by impulsivity, distractibility and hyperactivity. In the pathogenesis of ADHD genetic and non-genetic factors play an important role. It is assumed that one of non-genetic factors should be oxidative stress. Pycnogenol®, an extract from the pine bark, consists of bioflavonoids, catechins, procyanidins and phenolic acids. Pycnogenol® acts as powerful antioxidant, chelating agent; it stimulates the activities of some enzymes, like SOD, eNOS, and exhibits other biological activities. Aim: The aim of this randomized, double-blind, placebo-controlled trial was to investigate the influence of administered Pycnogenol® or placebo on the level of reduced (GSH) and oxidized (GSSG) glutathione in children suffering from ADHD and on total antioxidant status (TAS). This is the first investigation of the redox glutathione state in relation to ADHD. Results: One month of Pycnogenol® administration (1 mg/kg body weight/day) caused a significant decrease in GSSG and a highly significant increase in GSH levels as well as improvement of GSH/GSSG ratio in comparison to a group of patients taking a placebo. TAS in children with ADHD was decreased in comparison with reference values. Pycnogenol® administration normalizes TAS of ADHD children.

Psychiatric Disorders and Polyphenols: Can They Be Helpful in Therapy?

The prevalence of psychiatric disorders permanently increases. Polyphenolic compounds can be involved in modulation of mental health including brain plasticity, behaviour, mood, depression, and cognition. In addition to their antioxidant ability other biomodulating properties have been observed. In the pathogenesis of depression disturbance in neurotransmitters, increased inflammatory processes, defects in neurogenesis and synaptic plasticity, mitochondrial dysfunction, and redox imbalance are observed. Ginkgo biloba, green tea, and Quercus robur extracts and curcumin can affect neuronal system in depressive patients. ADHD patients treated with antipsychotic drugs, especially stimulants, report significant adverse effects; therefore, an alternative treatment is searched for. An extract from Ginkgo biloba and from Pinus pinaster bark, Pycnogenol, could become promising complementary supplements in ADHD treatment. Schizophrenia is a devastating mental disorder, with oxidative stress involved in its pathophysiology. The direct interference of polyphenols with schizophrenia pathophysiology has not been reported yet. However, increased oxidative stress caused by haloperidol was inhibited ex vivo by different polyphenols. Curcumin, extract from green tea and from Ginkgo biloba, may have benefits on serious side effects associated with administration of neuroleptics to patients suffering from schizophrenia. Polyphenols in the diet have the potential to become medicaments in the field of mental health after a thorough study of their mechanism of action.

WITHDRAWN: Natural polyphenols modify trace element status and improve clinical symptoms of attention-deficit hyperactivity disorder.

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Psychiatric disorders and omega-3 fatty acids.

Psychiatric disorders, especially mood disorders in children and adolescent are serious problem of all over the world in the field of child and adolescent psychiatry. In the recent years mood disorders occur in the earlier age. The prevalence of major depression (MD) is about 1-2% in preadolescent children and 3-8% in adolescents. When the major depression is not treated there is a big risk of worsening of symptoms, risk of suicide and development of comorbid disorders. The quality of life of the patient and its family is decreasing in the whole view. The molecular basis of major depression is not well known. The main pathomechanism of MD is in noradrenergic, serotonergic and dopaminergic pathway dysregulation, nutition factors, which can influence structure and metabolism of lipids. It was found decreased level of omega 3 fatty aids (FA), increased ratio of omega 6/omega 3 FA in the serum and in erythrocyte membrane. It is supposed that the oxidative neuronal injury can be prevented by dietary supplementation of antioxidants and that membrane phospholipids can be repaired by dietary supplementation of fatty acids. Omega-3 fatty acids may also participate in modulation of membrane fluidity, which influences the transmission of neurotransmitters. The membrane fluidity is affected by the ratio of phospholipids to free cholesterol. In addition, activation of the inflammatory response was found in depressive patients through increased production of pro-inflammatory cytokines (IL-1b, IL-6, interferon gamma, TNF-alpha) and eicosanoids (prostaglandin E2) in blood and cerebrospinal fluid. This results in increased lipid peroxidation and degradation of polyunsaturated fatty acids, which may result in increased oxidative stress. Omega-3 fatty acids also stimulate anti-inflammatory cytokines (IL-10) or inhibit the cyclooxygenase, platelet aggregation and formation of eicosanoids. The potential molecular mechanisms will be discussed.