Urinary catecholamines in children with attention deficit hyperactivity disorder (ADHD): modulation by a polyphenolic extract from pine bark (pycnogenol).

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.

Association of metabolic syndrome risk factors with selected markers of oxidative status and microinflammation in healthy omnivores and vegetarians.

Conditions predisposing to metabolic syndrome (MetS) are associated with increased oxidative stress and inflammation. We studied, in vegetarians (n = 90) and omnivores (n = 46), the impact of the dietary regimen on the occurrence of MetS risk factors (RFs: BMI, blood pressure, glucose metabolism and lipid profile) in relation to oxidative status (advanced glycation end products (AGEs), advanced oxidation protein products (AOPPs), malondialdehyde, ferric reducing ability of plasma, vitamins A, E, C, beta-carotene and superoxide dismutase activity) and microinflammation (C-reactive protein, leukocytes and neopterin). The proportion of subjects without/positive for one or two MetS RFs was comparable between the groups. From the components of MetS only immunoreactive insulin levels differed significantly (95% CI: omnivores: 5.0-7.1 microU/mL, vegetarians: 4.5-5.4, p = 0.03). Omnivores had lower AOPP (omnivores: 0.29-0.36 micromol/g albumin, vegetarians: 0.36-0.52, p = 0.01) and beta-carotene levels than vegetarians, they consumed more calories, proteins, fat and saturated fatty acids, and less fibres, beta-carotene and vitamin C. Multiple regression analysis revealed vitamin E and AOPP levels as the most important independent determinants of MetS RFs. The vegetarian diet seems to exert beneficial effects on MetS RFs associated microinflammation. Whether the vegetarian diet may counteract the deleterious effects of elevated AOPPs and AGEs, remains to be elucidated.

Reduced plasma homocysteine levels in levodopa/entacapone treated Parkinson patients.

Hyperhomocysteinemia is not only a major risk factor for atherothrombotic disease, but is also strongly associated with an increased risk of dementia and cognitive impairment, both of which are common in the course of Parkinson's disease (PD). Previous work has found that levodopa increases plasma homocysteine concentrations. Animal studies have indicated that the catechol-O-methyltransferase (COMT) inhibitors can prevent levodopa-induced elevation of homocysteine concentrations by reducing the O-methylation of levodopa. The objective of our study was to assess the impact of entacapone, a COMT inhibitor, on plasma levels of homocysteine, serum folate, and vitamin B12 in levodopa-treated PD patients. Nineteen PD patients receiving only levodopa and 21 PD patients on a combination of levodopa and entacapone participated in the cross-sectional study. The control group consisted of 17 subjects on dopamine agonists. The mean plasma homocysteine concentration in the subjects on only levodopa was higher than that in the subjects on a combination of levodopa and entacapone (P=0.001) or in the control group (P=0.0001). Concentrations of serum vitamin B12 and serum folate were on average normal in all groups, but levodopa-treated subjects (with or without entacapone therapy) were more prone to have hypovitaminosis B12 (45%) than controls on dopamine agonists (6%). We suggest that the COMT inhibition may play a promising role in successfully controlling levodopa-induced hyperhomocysteinemia and in reducing the risk of pathologies probably linked to it. These preliminary findings and postulated hypotheses must now be confirmed in prospective studies.

Repeated stress-induced stimulation of catecholamine response is not followed by altered immune cell redistribution.

Stress response is considered an important factor in the modulation of immune function. Neuroendocrine hormones, including catecholamines, affect the process of immune cell redistribution, important for cell-mediated immunity. This longitudinal investigation was aimed at evaluating the effect of repeated stress-induced elevation of catecholamines on immune cell redistribution and expression of adhesive molecules. We assessed the responses of epinephrine (EPI), norepinephrine (NE), cortisol, changes in lymphocytes subpopulations, and percentages of CD11a+, CD11b+, and CD62L+ lymphocytes to a 20-min treadmill exercise of an intensity equal to 80% of the individual's Vo(2)max. The exercise was performed before and after 6 weeks of endurance training consisting of a 1-h run 4 times a week (ET) and after 5 days of bed rest (HDBR) in 10 healthy males. We did not observe any significant changes in the basal levels of EPI, NE, and cortisol in the plasma, nor in the immune parameters after ET and HDBR. The exercise test led to a significant (P <.001) elevation of EPI and NE levels after both ET and HDBR, a significant elevation (P <.01) of cortisol after HDBR, an increase in the absolute numbers of leukocytes, granulocytes, monocytes, CD3+, CD4+, CD8+, CD16+, CD19+ lymphocytes, percentage of CD11a+ and CD11b+ lymphocytes, and to a decrease of CD62L1 before, after ET, and after HDBR. We found comparable changes in all measured immune parameters after ET and HDBR. In conclusion, repeated stress-induced elevation of EPI and NE was not associated with an alteration in immune cell redistribution found in response to the single bout of exercise.

Seasonal changes in markers of oxidative damage to lipids and DNA; correlations with seasonal variation in diet.

We have addressed the question whether the relatively high incidence of cardiovascular disease and certain cancers in countries of central/eastern Europe might be associated with nutritional imbalance, in particular a lack of fresh fruit and vegetables in the diet in winter months. Nutritional parameters and markers of oxidative stress were studied in three Slovak population groups: 46 survivors of myocardial infarction (MI group) and 48 healthy, normolipidemic subjects (NL), living in or near Bratislava; and 70 rural controls (RC group) living a more traditional life style in a country town. Data were collected in February/March and September/October of two consecutive years, representing times of minimum and maximum local availability of fresh fruits and vegetables. Oxidative stress was monitored using two biomarkers; plasma malondialdehyde (MDA, a product of lipid peroxidation), and oxidation of lymphocyte DNA. Dietary antioxidants, folic acid, homocysteine, total antioxidant status (FRAP) and uric acid were measured in plasma. Food frequency questionnaires were administered. Vegetable consumption in summer/autumn was twice as high as in winter/spring. DNA damage did not vary consistently across the seasons. Mean plasma MDA levels for the MI and NL groups showed a clear pattern, with high levels in winter/spring and low levels in summer/autumn. Folic acid showed a reciprocal pattern, similar to the pattern of vegetable consumption. The RC group had the smallest seasonal variations in vegetable consumption, folic acid levels, and MDA. High winter MDA levels are seen in those individuals with relatively low folic acid; they never occur in subjects with high plasma folic acid, implying that folic acid might directly protect against lipid oxidation. This study illustrates the value of the molecular epidemiological approach, while emphasising the need for well characterised population groups and valid biomarkers.

Post-hatching dynamics of plasma biochemistry in free-living European starlings (Sturnus vulgaris).

This is the first study of plasma biochemical parameters in free-living altricial birds during an entire developmental period in a nest, represented by European starling (Sturnus vulgaris). Dynamics of postnatal changes from hatching until close to fledging (days 1 to 15) were registered. Parameters of protein metabolism represented by total proteins, albumin and globulin concentrations increased continuously during the observed developmental period. There were two peaks in uric acid concentration on days 5 and 11. To the contrary, the creatinine content did not change throughout the observed period and increased only on day 15. Creatine kinase activity gradually increased until day 11 and then fell before fledging. Parameters of lipid metabolism (concentration of total lipids, triacylglycerols and nonesterified fatty acids) in plasma increased gradually reaching a plateau between days 8 and 11 and then declined on day 15. The cholesterol concentration pattern was similar to maximum value on day 11, then consecutively decreased. Concentration of glucose increased until day 8 and remained unchanged until fledging. Whereas calcium reached the highest concentration during days 8 and 11, phosphorus peaked earlier on day 5. The activity of alkaline phosphatase was similar to the pattern found in calcium concentration. Presented data showed an increase in both protein and lipid metabolism during the phase of rapid growth. A remarkable decrease in parameters of lipid metabolism before fledging may reflect increased physical activity and changes in nutrition.