The Assessment of the Socioemotional Disorder in Neurodegenerative Diseases with the Revised Self-Monitoring Scale (RSMS).

BACKGROUND: Social cognition helps people to understand their own and others' behavior and to modulate the way of thinking and acting in different social situations. Rapid and accurate diagnoses of neurodegenerative diseases are essential, as social cognition is affected by these diseases. The Revised Self-Monitoring Scale (RSMS) is a scale that detects social-emotional cognition deficits. AIM: The aim of the current study is to examine how socioemotional parameters are affected by neurodegenerative diseases and whether the RSMS can discern these disorders based on the socioemotional parameters in the Greek population. METHODS/DESIGN: A total of 331 dementia subjects were included. Mini Mental State Examination (MMSE) and Addenbrooke's Cognitive Examination (Revised, ACE-R) measurements were used in order to assess the cognitive deficits. The Neuropsychiatric Inventory (NPI) was used for the evaluation of the neuropsychiatric symptoms. The RSMS and its two subscales was used in order to detect the socioemotional deficits. RESULTS: The RSMS and its two subscales (RSMS_EX and RSMS_SP) can effectively detect neurodegenerative diseases. The RSMS can detect bvFTD in Alzheimer's Disease (AD), AD in a healthy cohort, behavioral variant Frontotemporal Dementia (bvFTD) in a healthy cohort, bvFTD in Parkinson's Disease (PD) and Frontotemporal Semantic Dementia (FTD/SD) in a healthy cohort. It is a useful tool in order to detect frontotemporal dementias. RSMS correlated negatively with the NPI questionnaire total and the subcategories of apathy, disinhibition and eating disorders. The RSMS results are associated with the ACE-R score (specifically verbal fluency). CONCLUSIONS: The RSMS is a helpful tool in order to identify socioemotional deficits in neurodegenerative dementias. It is also a useful scale that can discern bvFTD and svPPA in AD patients. A worse RSMS score correlates with a worse ACE-R and NPI. It seems to be a useful scale that can reliably measure social behavior in non-reversible neurodegenerative disorders, such as AD, FTD (bvFTD, svPPA), PDD and PD. The results also apply to the Greek population.

The relationship between neurotransmission-related amino acid blood concentrations and neuropsychological performance following acute exercise.

Amino acid neurotransmitters, including glutamate, phenylalanine, tyrosine, alanine, and glycine, underlie the majority of the excitatory and inhibitory neurotransmission in the nervous system, and acute exercise has been shown to modulate their concentrations. We aimed to determine whether any correlation exists between the above-mentioned amino acid blood concentrations and the neuropsychological performance after an acute exercise intervention. Sixty basketball players were randomly assigned to one of two experimental conditions: exercise or inactive resting. All participants underwent a comprehensive neuropsychological assessment and blood samples were taken on a Guthrie card before and after the end of the experimental conditions. Amino acid blood concentrations were significantly elevated and cognitive performance significantly improved post-exercise on specific neuropsychological assessments. Significant intervention × group interaction effects were apparent for Trail Making Test part-B [F(1,58) = 20.46, p < .0001, η2 = .26] and Digit Span Backwards [F(1,58) = 15.47, p < .0001, η2 = .21] neuropsychological assessments. Additionally, regression analysis indicated that tyrosine accounted for 38.0% of the variance in the Trail Making Test part-A test. These results suggest that elevated blood concentrations of neurotransmission-related amino acids are associated with improved neuropsychological performance after a single bout of high-intensity exercise.

The Progressive Supranuclear Palsy: Past and Present Aspects.

Objectives: Recently, new criteria for sensitive and specific clinical diagnosis of progressive supranuclear palsy (PSP) have been addressed while distinct clinical phenotypes of the disorder have been increasingly described in the literature. This study aimed to describe past and present aspects of the disease as well as to highlight the cognitive and behavioral profile of PSP patients in relation to the underlying pathology, genetics and treatment procedures.Methods: A Medline and Scopus search was performed to identify articles published on this topic. Articles published solely in English were considered.Results: The most common clinical characteristics of PSP included early postural instability and falls, vertical supranuclear gaze palsy, parkinsonism with poor response to levodopa and pseudobulbar palsy. Frontal dysfunction and verbal fluency deficits were the most distinct cognitive impairments in PSP while memory, visuospatial and social cognition could also be affected. Apathy and impulsivity were also present in PSP patients and had significant impact on relatives and caregivers.Conclusions: PSP is a neurodegenerative disorder with prominent tau neuropathology. Movement, motivation and communication impairments in patients with PSP may limit participation in everyday living activities. Comprehensive neuropsychological assessments are of significant importance for PSP cognitive evaluation. Pharmacologic and non-pharmacologic approaches could be applied in order to relieve patients and improve quality of life.Clinical Implications: Executive dysfunction is the most notable cognitive impairment and dominates the neuropsychological profile of patients with PSP.

The power of sample size through a multi-scanner approach in MR neuroimaging regression analysis: evidence from Alzheimer's disease with and without depression.

The inconsistency of volumetric results often seen in MR neuroimaging studies can be partially attributed to small sample sizes and variable data analysis approaches. Increased sample size through multi-scanner studies can tackle the former, but combining data across different scanner platforms and field-strengths may introduce a variability factor capable of masking subtle statistical differences. To investigate the sample size effect on regression analysis between depressive symptoms and grey matter volume (GMV) loss in Alzheimer's disease (AD), a retrospective multi-scanner investigation was conducted. A cohort of 172 AD patients, with or without comorbid depressive symptoms, was studied. Patients were scanned with different imaging protocols in four different MRI scanners operating at either 1.5 T or 3.0 T. Acquired data were uniformly analyzed using the computational anatomy toolbox (CAT12) of the statistical parametric mapping (SPM12) software. Single- and multi-scanner regression analyses were applied to identify the anatomical pattern of correlation between GM loss and depression severity. A common anatomical pattern of correlation between GMV loss and increased depression severity, mostly involving sensorimotor areas, was identified in all patient subgroups imaged in different scanners. Analysis of the pooled multi-scanner data confirmed the above finding employing a more conservative statistical criterion. In the retrospective multi-scanner setting, a significant correlation was also exhibited for temporal and frontal areas. Increasing the sample size by retrospectively pooling multi-scanner data, irrespective of the acquisition platform and parameters employed, can facilitate the identification of anatomical areas with a strong correlation between GMV changes and depression symptoms in AD patients.

The Neural Correlates of Impaired Self-Monitoring Among Individuals With Neurodegenerative Dementias.

OBJECTIVE: Self-monitoring is a crucial component of human empathy and necessary for the formation and repair of social relations. Several studies have brought to light possible neuronal substrates associated with self-monitoring, but the information that they have provided is inconclusive. The authors, therefore, studied a large group of patients with dementia to assess what brain structures are necessary for the self-monitoring function.Methods: Seventy-seven patients with dementia of various types were screened using voxel-based morphometry to assess possible volume reduction in the brain structures of patients with self-monitoring problems, and the decrease of socioemotional expressiveness and modification of self-presentation was estimated using the Revised Self-Monitoring Scale. Regression analysis was employed to investigate the correlation between gray matter loss and deficient self-monitoring.Results: The socioemotional expressiveness scores were associated with decreased gray matter volume in the right olfactory cortex, inferior frontal gyrus, superior temporal pole, parahippocampal gyrus, insula, and medial temporal gyrus bilaterally. Self-presentation scores were associated with bilateral gray matter volume reduction in the olfactory cortex, insula, rectus gyrus and inferior frontal gyrus, right superior temporal pole, and parahippocampal gyrus, as well as the left medial temporal gyrus and anterior superior frontal gyrus.Conclusions: These results suggest that patients with dementia present decreased ability of self-monitoring, probably due to impaired insula and orbitofrontal cortex and their disconnection from structures of the salience network.

A specific pattern of gray matter atrophy in Alzheimer's disease with depression.

Considering the high incidence of depressive symptoms in Alzheimer's disease (AD), we conducted a large-sample study to investigate the pattern of gray matter (GM) abnormalities that differentiates depressive from non-depressive AD patients. We included 201 AD patients who underwent MRI assessment and categorized them into depressive and non-depressive subgroups based on the Geriatric Depression Scale (GDS; cut-off score: ≤9). We performed whole-brain voxel-based morphometry analysis in 173 patients after MRI quality control and used between-group comparisons and regression analysis models to analyze the volumetric data controlling for nuisance variables. Depressive AD patients had extensive GM volume loss mainly in the paracentral region, specifically in post- and pre-central gyrus, supplementary motor areas and thalamus compared to non-depressive patients. Similar findings were obtained for the group of 173 patients using regression analysis and GDS score as predictor variable. We provided the first clear demonstration of a unique pattern of GM atrophy that characterizes AD patients with depression which is consistent with regions implicated in the phenomenon of psychomotor retardation that characterizes depression.

Evidence for the participation of the stimulated sympathetic nervous system in the regulation of carnitine blood levels of soccer players during a game.

Catecholamines and carnitine blood levels are closely implicated with training. The aim of the study was to investigate the effect of sympathetic nervous system stimulation on carnitine and its fraction levels during training. Blood was obtained from 14 soccer players pregame, at intermission, and postgame. Catecholamines were measured with high-performance liquid chromatography methods; muscle enzymes creatine kinase and lactate dehydrogenase as well as lactate, pyruvate, and total antioxidant status with commercial kits; and carnitine and fraction levels with tandem mass spectrometry. Total antioxidant status (2.97 +/- 0.13 vs 0.96 +/- 0.10 mmol/L, P < .01) as well as free carnitine levels (20.47 +/- 4.0 vs 12.30 +/- 2.8 micromol/L, P < .001) were remarkably decreased especially postgame. Total acylcarnitines (5.20 +/- 1.8 vs 9.42 +/- 3.0 micromol/L, P < .001) and especially total very long-chain acylcarnitines (0.80 +/- 0.01 vs 1.85 +/- 0.03 micromol/L, P < .001) as well as catecholamine levels (adrenaline: 230 +/- 31 vs 890 +/- 110 pmol/L, P < .01; noradrenaline: 1.53 +/- 0.41 vs 3.7 +/- 0.6 nmol/L, P < .01) were significantly increased in players postgame. A statistically significant inverse correlation was found between adrenaline and free carnitine (r = -0.51, P < .01); and a positive correlation was found between adrenaline, total acylcarnitines (r = 0.58, P < .01), and total long-chain acylcarnitine (r = 0.49, P < .01). The significant positive correlation of adrenaline levels with total acylcarnitine and total long-chain acylcarnitine blood levels in athletes as well as the inverse correlation with free carnitine levels may indicate participation of the stimulated sympathetic nervous system in the regulation of some carnitine fraction levels during exercise.

The effect of the mode of delivery on the maternal-neonatal erythrocyte membrane acetylcholinesterase activity.

UNLABELLED: Free radical production and high catecholamine levels are implicated with the modulation of acetylcholinesterase (AChE) activity. OBJECTIVE: To investigate the effect of the mode of delivery on maternal-neonatal erythrocyte membrane AChE activity. SUBJECTS AND METHODS: Some women with normal pregnancy (N = 30) were divided into two groups: group A (N = 16) with normal labour and vaginal delivery and group B (N = 14) with scheduled Cesarean section, twenty non-pregnant women were the controls. Blood was obtained from controls and from mothers pre- vs post-delivery as well as from the umbilical cord (CB). Total antioxidant status (TAS), membrane AChE activities and catecholamine blood levels were measured with a commercial kit, spectrophotometrically and HPLC methods, respectively. RESULTS: TAS and catecholamine levels as well as membrane AChE activities were similar in the two groups of mothers pre-delivery and in controls. TAS levels were reduced whereas AChE activities and catecholamine levels were increased post-delivery in mothers of group A and unaltered in group B at the same times of study. AChE activity was similarly lower in the CB of neonates than those of their mothers pre-delivery. CONCLUSIONS: During a normal delivery process, the low TAS, the increased levels of catecholamines and the increased AChE activity, post-delivery, may be due to the increased stress due to the participation of uterus and skeletal muscles as during endurance exercise. The low AChE activity in newborns may be related to perinatal immaturity.

Maternal-neonatal erythrocyte membrane Na(+), K (+)-ATPase and Mg (2+)-ATPase activities in relation to the mode of delivery.

Free radical production and high catecholamine levels are implicated in the modulation of Na(+), K(+)-ATPase, and Mg(2+)-ATPase activities. The aim of this study was to investigate the effect of the mode of delivery on the above-mentioned enzyme activities in maternal-neonatal erythrocyte membrane. Women with normal pregnancy (N = 30) were divided into two groups: Group A (N = 16) with normal labor and vaginal delivery, and Group B (N = 14) with scheduled cesarean section; 20 non-pregnant women were the controls. Blood was obtained from controls and mothers, pre- versus post-delivery, and from the umbilical cord (CB). Total antioxidant status (TAS), membrane enzyme activities, and catecholamine blood levels were measured with a commercial kit, spectrophotometrically, and by HPLC methods, respectively. The results showed that: TAS levels, catecholamine, and the membrane enzyme activities were similar in the two groups of mothers pre-delivery, whereas both enzyme activities were lower than those of controls. TAS levels were reduced whereas Na(+), K(+)-ATPase activities (0.35 +/- 0.03 vs. 0.65 +/- 0.06 micromol Pi/h x mg protein, P < 0.001), and catecholamine levels were increased post-delivery in mothers of Group A and unaltered in Group B (0.38 +/- 0.02 vs. 0.40 +/- 0.03 micromol Pi/h x mg protein, P > 0.05), at the same times of study. Mg(2+)-ATPase activities remained unaltered in both groups of mothers and newborns. Na(+), K(+)-ATPase activity was similarly lower in the CB of neonates than those of their mothers, pre-delivery. Our results suggest that: (a) during a normal vaginal delivery process, the low TAS and the increased levels of catecholamines may increase Na(+), K(+)-ATPase activity, post-delivery; (b) the low enzyme activities evaluated in mothers pre-delivery may be due to the high estrogen levels and those in newborns due to perinatal immaturity.

The in vivo and in vitro effects of L-carnitine supplementation on the erythrocyte membrane acetylcholinesterase, Na+, K+-ATPase and Mg2+-ATPase activities in basketball players.

BACKGROUND: We investigated whether the activities of erythrocyte membrane acetylcholinesterase (AChE), Na+, K+-ATPase and Mg2+-ATPase are modulated in basketball players pre- vs. post-forced training with or without L-carnitine (L-C) supplementation. METHODS: Blood was obtained from 10 male players pre-game (group A) and post-game (group B) and after 1 month L-C supplementation (2 g/24 h orally) pre-training (group C) and post-training (group D). Lactate, pyruvate and total antioxidant status (TAS) were measured with commercial kits, catecholamines with HPLC and the enzyme activities spectrophotometrically. RESULTS: Lactate, pyruvate, AChE, Na+, K+-ATPase and catecholamines were increased (p<0.001) and TAS was decreased (p<0.001) in group B. In contrast, TAS remained unaltered and the all enzyme activities were reduced (p<0.001) in group D at the same time of study. Mg2+-ATPase activity remained unchanged. In vitro incubation of the modulated AChE and Na+, K+-ATPase with L-C (25 microM) from group B and group D resulted in a non-significant reduction of the enzymes in group B and complete restoration of their activities in group D. CONCLUSIONS: The increase of AChE and Na+, K+-ATPase activities may be due to the elevation of catecholamines in group B. Carnitine utilization by the muscles during training may result in a reduction of the enzyme activities (group D). The latter is supported by the recovery of the enzyme activities after incubation of the membranes from group D with L-C.

The effect of alpha-Tocopherol supplementation on training-induced elevation of S100B protein in sera of basketball players.

OBJECTIVE: To investigate the effect of alpha-Tocopherol (alpha-T) supplementation on S100B elevated serum levels in basketball players' training. DESIGN: Blood was obtained from 10 basketball players pre-exercise (group A), post-exercise (group B) and after 30 days on alpha-T (200 mg/24 h orally) supplementation pre- (group C) and post-training (group D). Blood samples were taken for the evaluation of total antioxidant status (TAS), alpha-T and catecholamines in plasma and S100B and muscle enzyme levels in serum. METHODS: TAS, muscle enzymes: creatine kinase (CK), lactate dehydrogenase (LDH), and S100B protein levels were measured with commercial kits, whereas alpha-T and catecholamine levels with HPLC methods. RESULTS: TAS was found higher in the groups with alpha-T addition (groups C and D) than in the other ones. On the contrary, CK, LDH and S100B were remarkably lower (116.8+9.5 U/L, 427+22 U/L, 0.18+0.04 microg/L, respectively) in group D than those in group B (286+12 U/L, 688+26 U/L, 0.28+0.06 microg/L, p<0.001, respectively). S100B levels were negatively correlated with TAS (r=-0.64, p<0.001) and positively with CK levels (r=0.58, p<0.001). CONCLUSIONS: alpha-T supplementation may reduce S100B increased release from muscle and nerves induced by training. S100B serum evaluation may be a useful biomarker for the effect of training on the participation of the neuromuscular system.

L-cysteine supplementation prevents exercise-induced alterations in human erythrocyte membrane acetylcholinesterase and Na+,K+-ATPase activities.

BACKGROUND: L-Cysteine (L-Cys) is implicated in the reduction of free radical production. The aim of this study was to investigate whether L-Cys supplementation prevents modulation of the activities of erythrocyte membrane acetylcholinesterase (AChE), Na(+),K(+)-ATPase and Mg(2+)-ATPase induced by free radicals in basketball players during training. METHODS: Blood was obtained from 10 basketball male players before (group A) and after a game (group B) and after 1 week of L-Cys (0.5 g/24 h orally) supplementation before (group C) and after training (group D). Lactate, pyruvate and total antioxidant status (TAS) were measured using commercial kits and the enzyme activities were determined spectrophotometrically. RESULTS: Both lactate and pyruvate levels remarkably increased after exercise. In contrast, TAS levels significantly decreased in group B, increased in group C and then declined (group D), reaching those of group A. AChE activity was statistically increased post-exercise (3.98+/-0.04 Delta OD/min x mg protein) compared with pre-training (2.90+/-0.05 Delta OD/min x mg protein, p<0.01). Na(+),K(+)-ATPase activity was also higher post-exercise (1.27+/-0.05 micromol Pi/h x mg protein) than that pre-exercise (0.58+/-0.04 micromol Pi/h x mg protein, p<0.001). When the players were supplemented with L-Cys, both AChE and Na(+),K(+)-ATPase activities remained unaltered post-exercise. Mg(2+)-ATPase activities were unchanged in all groups studied. CONCLUSIONS: L-Cys supplementation may protect the enzyme activities studied against stimulation induced by free radical production during training in athletes by ameliorating their total antioxidant capacity.

An in vivo and in vitro study of erythrocyte membrane acetylcholinesterase, (Na+, K+)-ATPase and Mg2+-ATPase activities in basketball players on alpha-tocopherol supplementation. The role of L-carnitine.

BACKGROUND & AIMS: Vitamin E (alpha-tocopherol, alpha-Te) and carnitine reduce lipid peroxidation. THE AIM WAS TO: To investigate the erythrocyte membrane acetylcholinesterase (AChE), Na+, K+-ATPase and Mg2+-ATPase activities in basketball players with or without alpha-Te supplementation, before and after training. In vitro, we aimed to find out any additional effect of L-carnitine (L-C) on the modulated enzyme activities. SUBJECTS AND METHODS: Blood was obtained from 10 players before (group A), after exercise (group B) and after 1 month on alpha-Te (200 mg/24 h orally) supplementation before (group C) and after the game (group D). Lactate, pyruvate, muscle enzyme activities and total antioxidant status (TAS) were measured with commercial kits. Catecholamines and alpha-Te were determined with HPLC methods and membrane enzyme activities spectrophotometrically. RESULTS: Lactate, pyruvate, muscle enzymes and catecholamine levels were increased (P<0.001) in all groups after training. Alpha-Te levels and Mg2+-ATPase activity remained unaltered before and after exercise. TAS was decreased in the groups after the game. AChE activity was increased in group B (P<0.01) and decreased in group D (P<0.01). After the exercise, Na+, K+-ATPase activity was increased in group B and remained unaltered in group D. In vitro incubation of membranes from group D with L-C resulted in a partially restoration of the membrane AChE activity, whereas Na+, K+-ATPase and Mg2+-ATPase activities were found unchanged. CONCLUSIONS: Alpha-Te supplementation in basketball players results in an increase of TAS and AChE activity, whereas the other enzyme activities were found unchanged. L-C addition may restore AChE activity, which was modulated by training in players on alpha-Te.

L-cysteine supplementation protects the erythrocyte glucose-6-phosphate dehydrogenase activity from reduction induced by forced training.

BACKGROUND: L-cysteine (L-cys) is implicated in the reduction of free radical production. AIM: To investigate the effect of training and L-cys supplementation on the erythrocyte glucose-6-phosphate dehydrogenase (G6PD) activity. METHODS: Blood was obtained from 10 basketball players pre-game (group A), post-game (group B) and after 1 week on L-cys (0.5 g/24 h orally) supplementation pre- (group C) and post-training (group D). Total antioxidant status (TAS) and G6PD activity were evaluated with commercial kits. RESULTS: TAS increased in the groups with l-cys addition (group C and group D). Post-exercise, TAS and G6PD activity were remarkably higher (1.48+/-0.12 mmol/L, 8.9+/-1.7 U/g Hb, respectively) in group D than those in group B (0.92+/-0.10 mmol/L, 4.8+/-1.6 U/g Hb, p<0.01). G6PD activity positively correlated with TAS (r=0.70, p<0.001 pre- and r=0.61, p<0.001 post-training) in all the studied groups. CONCLUSIONS: G6PD activity is lowered by training probably due to free radical action. L-cys supplementation may protect G6PD activity from reduction by increasing total antioxidant capacity and glutathione production. G6PD activity should be evaluated in the blood of athletes of Mediterranean origin and female G6PD-deficient heterozygotes.

alpha-Tocopherol supplementation restores the reduction of erythrocyte glucose-6-phosphate dehydrogenase activity induced by forced training.

BACKGROUND: Erythrocyte glucose-6-phosphate dehydrogenase (G6PD) activity is closely related to free radical production. alpha-Tocopherol (alpha-T) is implicated with the reduction of lipid peroxidation. AIM: To investigate the effect of training and alpha-T supplementation on the erythrocyte G6PD activity. METHODS: Blood was obtained from 10 basketball players pre-game (group A), post-game (group B) and after 30 days on alpha-T (dl-alpha-tocopheryl-acetate, 200mg 24h(-1) orally) supplementation pre- (group C) and post-training (group D). alpha-T and catecholamines were evaluated with HPLC methods and creatine kinase, lactate dehydrogenase, total antioxidant status (TAS) and G6PD activity with commercial kits. RESULTS: TAS was increased in the groups with alpha-T addition (groups C and D). Post-exercise, TAS and G6PD activity were remarkably higher (2.10+/-0.13mmoll(-1), 7.92+/-1.5Ug(-1)Hb, respectively) in group D than those in group B (0.92+/-0.10mmoll(-1), 4.8+/-1.4Ug(-1)Hb, p<0.01, respectively). G6PD activity positively correlated with TAS (r=0.64, p<0.001) in all the studied groups. CONCLUSIONS: Supplementation with alpha-T may protect G6PD activity from reduction induced by forced training.

alpha-tocopherol supplementation reduces the elevated 8-hydroxy-2-deoxyguanosine blood levels induced by training in basketball players.

BACKGROUND: The aim of the present study was to investigate the effect of alpha-tocopherol (alpha-Te) supplementation on DNA oxidative damage induced by heavy training in basketball players. METHODS: Blood was obtained from 10 players before (group A) and after training (group B) and after 1 month on alpha-Te (200 mg/day, orally) supplementation, before (group C) and after training (group D). Total antioxidant status (TAS), muscle enzyme activities and the biomarker of DNA oxidation, 8-hydroxy-2-deoxyguanosine (8-OHdG), were measured using commercial kits. alpha-Te and catecholamine blood levels were determined using HPLC methods. RESULTS: TAS was higher in the groups with alpha-Te (groups C and D). Levels of 8-OHdG and muscle creatine kinase (CK) and lactate dehydrogenase (LDH) were remarkably lower (0.20+/-0.03 ng/mL, 120+/-15 U/L and 430+/-90 U/L, respectively) in the group with alpha-Te (group D) than in group B (0.42+/-0.05 ng/mL, 286+/-12 U/L and 688+/-88 U/L, respectively; p<0.001). 8-OHdG levels were negatively correlated to TAS and positively to CK levels. CONCLUSIONS: alpha-Te supplementation may reduce DNA oxidation induced by training by protecting muscle cell "death" from glutamate entry and/or by elevation of TAS via amelioration of lipid peroxidation.

Erythrocyte membrane Na+,K+-ATPase and Mg2+-ATPase activities in subjects with methylenetetrahydrofolate reductase (MTHFR) 677 C-->T genotype and moderate hyperhomocysteinaemia. The role of L-phenylalanine and L-alanine.

BACKGROUND: Increased homocysteine (Hcy) blood levels are correlated with vascular and neurological problems. The aim of our study was to investigate erythrocyte membrane Na(+),K(+)-ATPase and Mg(2+)-ATPase activities in patients with methylenetetrahydrofolate reductase (MTHFR) 677 C-->T genotype. METHODS: Blood was obtained from 25 patients before and after folic acid supplementation and from controls (n=30) once. Plasma folate, vitamin B(12) and total antioxidant status (TAS) were measured using commercial kits, Hcy was determined by HPLC and membrane enzyme activities were measured spectrophotometrically. RESULTS: Mg(2+)-ATPase remained unaltered. Membrane Na(+),K(+)-ATPase activity was remarkably increased in patients (0.77+/-0.06 micromol Pi/h x mg protein) and decreased to normal levels (0.52+/-0.05 micromol Pi/h x mg protein; p<0.001) after therapy. TAS did not differ significantly before and after treatment. Hcy levels were significantly higher before therapy (25.4+/-2.8 micromol/L) than levels after therapy (12.1+/-2.0 micromol/L; p<0.001) and in controls (10.5+/-2.5 micromol/L, p<0.001). In vitro, L-phenylalanine (Phe) reversed to normal the stimulated enzyme from patients before therapy. In addition, Phe incubation of the Hcy activated membrane Na(+),K(+)-ATPase from controls resulted in restoration of its activity, whereas L-alanine (Ala) incubation protected the enzyme from Hcy activation. CONCLUSIONS: The increased membrane Na(+),K(+)-ATPase activity may be due to high -SH group Hcy levels. In vitro, Phe reversed the increase in enzyme activity induced by Hcy in controls, as well as the stimulated membrane enzyme in untreated patients. Ala protected the enzyme from Hcy action.

The beneficial effect of L-cysteine supplementation on DNA oxidation induced by forced training.

BACKGROUND: Forced training is closely implicated with free radicals production and indication of tissue damage as well as DNA oxidation. AIM: To investigate the effect of L-cysteine (L-cys) supplementation on DNA oxidative damage found in basketball players after forced training. SUBJECTS AND METHODS: Blood was obtained from 10 players pre-game (group A), post-game (group B) and after 1 month L-cys (0.5 g 24 h(-1), orally) supplementation, pre- (group C) and post-training (group D). Total antioxidant status (TAS) and the biomarker of DNA oxidative damage 8-hydroxy-2-deoxyguanosine (8-OHdG) as well as creatine kinase (CK) and lactate dehydrogenase (LDH) were measured with commercial kits. RESULTS: TAS was increased in the groups with L-cys (group C and group D). Post-exercise 8-OHdG levels, CK and LDH were remarkably lower (0.16+/-0.03 ng ml(-1), 115+/-15 U l(-1), 417+/-90 U l(-1), respectively) in group D than those in group B (0.36+/-0.05 ng ml(-1), 286+/-12 U l(-1), 688+/-88U l(-1), p<0.001, respectively). 8-OH dG levels were negatively correlated with TAS(r=-0.718, p<0.01) and positively with CK levels(r=0.590, p<0.01). CONCLUSIONS: L-cys supplementation in basketball players may reduce DNA damage induced by training. The sulfur-containing amino acid may protect muscle cells "death" by increasing TAS and the cellular defense against oxidative stress.