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.