Acute variations in homocysteine levels are related to creatine changes induced by physical activity

Exercise-Induced Hyperhomocysteinemia Is Not Related to Oxidative Damage or Impaired Vascular Function in Amateur Middle-Aged Runners under Controlled Nutritional Intake

To determine the influence of different doses of maximal acute exercise on the kinetics of plasma homocysteine (tHcy) and its relationship with oxidative status and vascular function, nine recreational runners completed a 10 km race (10K) and a marathon (M). Blood samples were collected before (Basal), immediately post-exercise (Post0), and after 24 h (Post24). Nutritional intake was controlled at each sample point. A significant increase in tHcy was observed after both races, higher after M. Basal levels were recovered at Post24 after 10K, but remained elevated at Post 24 for M. A significant decrease in GSH/GSSG ratio was observed in Post0, especially marked after M. Furthermore, this increase in pro-oxidant status remained at Post24 only after M. Other oxidative status markers failed to confirm this exercise-induced pro-oxidant status except glutathione peroxidase activity that was lower in Post24 compared to Basal in 10K and in Post0 and Post24 in M. No statistical correlation was found between oxidative markers and tHcy. No significant changes were observed in the concentration of endothelial cell adhesion molecules (VCAM-1 and E-Selectin) and VEGF. In conclusion, tHcy increases in an exercise–dose–response fashion but is not related to endothelial dysfunction mediated by oxidative stress mechanisms.

Physical activity, body mass index and arsenic metabolism among Mexican women

BACKGROUND

In some epidemiological studies, a positive association of body mass index (BMI) with inorganic arsenic (iAs) metabolism parameters (percentage dimethylarsinic acid [%DMA] and secondary methylation index [SMI]) has been found. In iAs metabolism, S-Adenosyl methionine is converted to S-Adenosyl homocysteine. Sedentarism has been associated with a higher risk of hyperhomocysteinemia. Physical activity has shown an inconsistent negative association with BMI. Therefore, our objective was to evaluate whether physical activity is associated to iAs metabolism independently of BMI.

METHODS

We performed a cross-sectional secondary analysis on 800 non-diabetic women, ≥18 years, who participated as population controls in a previous study on breast cancer in northern Mexico. Participants were interviewed about physical activity during their lifetime, and their weight and size were obtained. Urinary arsenic metabolites concentrations were determined by high performance liquid chromatography coupled with mass spectrometry.

RESULTS

In the study population, total arsenic ranged from 0.71 to 303.29 μg/L, and the lifetime average physical activity from 0 to 788.40 min/week. BMI was significantly and negatively associated with percentage monomethylarsonic acid (%MMA) and primary methylation index (PMI), and positively associated with %DMA, SMI and TMI, respectively. Likewise, physical activity was negatively associated with %iAs and %MMA, and positively associated with %DMA, SMI and TMI. These results remained after BMI was adjusted for physical activity and viceversa.

CONCLUSION

This study confirms the relationship between BMI and iAs metabolism parameters and provides new evidence on the association between physical activity and iAs metabolism.

Classical homocystinuria, is it safe to exercise?

Background Cystationine β-synthase (CBS) deficiency is a genetic disorder characterized by severe hyperhomocysteinemia and thrombotic complications. In healthy individuals, physical exercise may result in a transient increase in plasma total homocysteine (tHcy) raising the possibility that exercise might be detrimental in CBS deficiency. Our main objective was to determine plasma tHcy kinetics in response to physical exercise in homocystinuria patients. Methods Six adult patients (2 males, 4 females) with homocystinuria and 6 age- and gender-matched controls completed a 30-min aerobic exercise of moderate-intensity with fixed power output (50 W for women and 100 W for men). Blood samples were drawn before, immediately, 180 min and 24 h after exercise. tHcy levels were determined by standard procedures; substrate oxidation and energy expenditure were measured using indirect calorimetry. Results Acute exercise was well tolerated and safe in patients and controls. During the exercise bout, heart rate and energy expenditure increased equally in both groups. tHcy levels were higher in patients compared to controls at all time points (p < 0.05). There was no significant effect of exercise on tHcy levels at any time point (p = 0.36). Although two patients with partial pyridoxine responsiveness presented higher homocysteine responses, their highest value remained below 55 μmol/l. Conclusions Overall metabolic responses to acute exercise were similar between homocystinuria patients and controls; specifically, exercise did not significantly change tHcy concentrations. Moderate physical exercise was well tolerated without any adverse event in our cohort of patients. Further studies are needed to identify the effects of different intensities and modes of exercise in larger cohorts of CBS patients with different levels of pyridoxine responsiveness.

The effect of aerobic vs. resistance training on plasma homocysteine in individuals with type 2 diabetes

Elevated plasma homocysteine concentration is a risk factor for cardiovascular disease, which seems to be the main cause of increased mortality in patients with type 2 diabetes. Previous studies have demonstrated the effect of exercise on homocysteine levels and the magnitude of these benefits seems to depend on the type, mode and frequency of training. The present study aimed to compare the effects of aerobic and resistance training on plasma homocysteine in individuals with type 2 diabetes. The study included 15 individuals undergoing aerobic training, 14 subjects undergoing resistance training, and 18 individuals in the control group. Homocysteine, total cholesterol and fractions, glucose, and anthropometric measurements were conducted. The training program lasted 16 weeks. Aerobic training was performed twice a week and lasted 75 min, and resistance training was performed twice a week and lasted 75 min. Homocysteine levels were not significantly different between before and after training. High-density lipoprotein levels increased in both training groups and decreased in the control group. Glucose levels decreased after aerobic and resistance training. Body fat mass (percentage and total) decreased in both training group, but with more expression in the aerobic group. We conclude that 16-week aerobic and resistance training programs did not significantly affect plasma homocysteine levels in patients with type 2 diabetes. Nevertheless, these training programs yielded positive results in HDL control, plasma glucose, and body composition.

Guanidinoacetic acid deficiency: a new entity in clinical medicine?

Guanidinoacetic acid (GAA, also known as glycocyamine or betacyamine) is a naturally-occurring derivative of glycine and a direct metabolic precursor of creatine, a key player in high-phosphate cellular bioenergetics. GAA is found in human serum and urine, with circulating GAA likely reflects an equilibrium between its endogenous production and utilization/excretion. GAA deficiency (as indicated by low serum GAA) has been reported in various conditions yet this intriguing clinical entity appears to be poorly characterized as yet, either as a primary deficit or a sequel of secondary disease. This minireview article summarizes the inherited and acquired disorders with apparent GAA deficiency and discusses a possible relevance of GAA shortfall in clinical medicine.

Age-Related Changes in Serum Guanidinoacetic Acid in Women

Guanidinoacetic acid (GAA) is a fundamental intermediate in cellular bioenergetics, with circulating levels of GAA often reflects disturbances in its conversion due to many intrinsic and extrinsic factors, including gender or age. Here, we evaluated serum GAA in 172 healthy women aged 18 to 65 years, with age found to significantly predict serum GAA concentrations (r=0.29; P=0.03). This perhaps nominates serum GAA as a novel gender-specific proxy of impaired bioenergetics with aging.

Rehydration during exercise prevents the increase of homocysteine concentrations

This study aimed to assess the effect of rehydration during and after acute aerobic submaximal exercise on total homocysteine (tHcy) concentrations and related parameters in physically active adult males. Twenty trained males (29.4 ± 7.9 years old) completed four exercise tests: two without rehydration during exercise (NH1 and NH2), one with rehydration during exercise using water (H1) and one with rehydration during exercise using an isotonic sports drink (H2). After finishing the exercise tests, subjects followed a rehydration protocol for 2 h. Serum tHcy, vitamin B12, folate, creatine and creatinine were analysed before, after and at 2, 6 and 24 h after exercise. Data were analysed with and without correcting for haemoconcentration to assess the changes in tHcy related. The methylenetetrahydrofolate reductase (MTHFR) 677TT genotype was also analysed. THcy (uncorrected by haemoconcentration) increased significantly after exercise (P < 0.05) in the NH1 and NH2 tests [mean increase ± SD: 1.55 ± 0.33 (15.18%) and 1.76 ± 0.25 (17.69%) µmol/L, respectively], while no significant differences were found in the H1 and H2 tests [mean increase: 0.65 (6.29%) and 0.90 (8.69%) μmol/L, respectively]. The increase was partly due to haemoconcentration and partly due to the metabolism underlying acute exercise. THcy concentrations recovered to baseline after 24 h in all tests. In conclusion, adequate rehydration during acute aerobic exercise using either water or a sports drink maintains tHcy concentrations at baseline and for up to 2 h after exercise in physically active male adults and prevents further increases when compared to no rehydration.

Acute exercise alters homocysteine plasma concentration in an intensity-dependent manner due increased methyl flux in liver of rats

PURPOSE

We aimed to determine the effects of different intensities of acute exercise on Hcy plasma levels, and the exercise-induced changes in Hcy liver metabolism.

METHOD

First, thirty-two Wistar rats were randomly submitted to an acute bout of swimming exercise carrying a load of 2% (n=8), 4% (n=8) and 6% (n=8) of their total body weight attached in their tail. Control rats remained rested (n=8). Blood samples were taken from tail vein for plasma S-containing amino acids determination before (Rest) and post, 1, 2, 3, 4, 6, and 10h after acute swimming exercise. Second, 56 exercised rats (4% loads) were euthanized before (Rest) and1, 2, 3, 4, 6, and 10h after acute swimming exercise. Blood and liver samples were collected for amino acids and keys genes involved in the Hcy metabolism assay.

RESULTS

Acute exercise increases (P<0.05) plasma Hcy concentration in an intensity-dependent manner (rest 7.7±0.8; 6% load 13.8±3.6; 4% load 12.2±2.9±and 2% load 10.1±2.6, μmol/L); this increase is transient and does not promote hyperhomocysteinemia (<15μmol/L).Exercise-induced increased plasma Hcywas accompanied by the decreased liver S-adenosylmethionine/S-adenosylhomocysteine ratio and elevated MAT1a mRNA content. Acute exercise also caused elevated mRNA of key enzymes of transsulfuration (CBS) and remethylation (BHMT and the MTRR).

CONCLUSION

Our data provided evidence that acute exercise increases plasma Hcy concentration due to the augmented requirement for methylated compounds that increases liver SAM consumption. Also, Hcy remethylation and transsulfuration are coordinately regulated to maintain methyl balance.

What do we know about homocysteine and exercise? A review from the literature

High total homocysteine (tHcy) concentrations contribute to an increased risk of cardiovascular diseases and neurodegenerative disorders. Several investigations have focused on the effect of exercise on tHcy concentrations, but results remain controversial. The differences among the methodologies in the investigations make difficult the interpretation of results. This review differentiates the effects of exercise on tHcy and establishes the relation with the implicated biomarkers on tHcy metabolism related to exercise. The electronic database MEDLINE (http://www.ncbi.nlm.nih.gov) was used for searching studies published between years 2002 and 2015. 'Homocysteine', 'Training ', 'Exercise', 'Physical Activity' as well as combinations out of these terms were entered in the database. Articles were grouped in: 1) Acute effect of exercise on tHcy, 2) chronic exercise and tHcy, 3) relationship of physical activity (PA) level and cardiorespiratory fitness with tHcy, and 4) biomarkers related to tHcy and exercise. From a total of 30 articles, most of the studies analyzing the acute effect of exercise showed an increase on tHcy concentrations. Studies analyzing the chronic effect on tHcy concentrations showed contradictory results and no consensus exists probably due to the differences in the methodology, exercise interventions and participants characteristics. Low cardiorespiratory fitness seems to be associated with high tHcy; in contrast, the relation of PA levels and tHcy needs further research. Regarding biomarkers related to tHcy and exercise, some studies showed an increase of folate, vitamin B12, and creatine after acute exercise that could to be due to requirement of protein turnover and an increased metabolic demand of vitamin-B.

Six-Week Oral Guanidinoacetic Acid Administration Improves Muscular Performance in Healthy Volunteers

BACKGROUND

Guanidinoacetic acid (GAA), a natural precursor of creatine, is a new promising dietary supplement, yet its performance-enhancing effect, if any, has yet to be established. The purpose of this pilot study was to evaluate the effects of supplemental GAA on muscle strength, anaerobic performance, and aerobic performance in healthy men and women.

METHOD

The study enrolled 48 young participants (age, 22.3 ± 1.5 years; height, 176.4 ± 10.0 cm; weight, 71.9 ± 14.3 kg), who received oral doses of GAA (1.2, 2.4, or 4.8 g/d) for 6 weeks in a randomized, double-blind, placebo-controlled trials.

RESULTS

Significant differences were observed between treatment groups for handgrip strength among participants receiving 1.2 g of GAA per day and 2.4 g of GAA per day, as compared with placebo (P < 0.05). In addition, muscle endurance expressed as the change from baseline in repetitions performed in the bench press exercise was significantly greater in the 1.2 g/d dose of GAA (P = 0.01) and the 4.8 g/d dose (P = 0.01) compared with placebo. No dose-response differences were found between trials.

CONCLUSIONS

Results from this preliminary study indicate that supplemental GAA ingested in young individuals can improve exercise performance, even at low doses (1.2 g/d).

Relationship between lifestyle factors and hyperhomocysteinemia in general Chinese population: a cross-sectional study

OBJECTIVES

Hyperhomocysteinemia (Hhcy) is a known cardiovascular disease (CVD) risk factor. Observational studies had supported the role of lifestyle factors such as physical activity, diet and alcohol consumption in CVD prevention. Our study aimed to determine the relationship between Hhcy and lifestyle factors in general Chinese population.

METHODS

In this cross-sectional study, a total of 7135 adults (3320 men and 3815 women) aged 35 years or older were recruited from the rural Northeast China. Data on lifestyle factors, such as physical activities, sleep duration, current smoking and drinking status, dietary habits and familial factors were collected in interviews and laboratory examinations were performed by well-trained personnel.

RESULTS

Plasma total homocysteine (tHcy) level was higher in men than in women, and greater in the elderly than in other age groups. Subjects with Hhcy were more likely to be current smokers (men: OR 1.328, 95% CI 1.143-1.543, p<0.001; women: OR 1.465, 95% CI 1.214-1.767, p<0.001). Separately, men with Hhcy were more likely to have an education of primary school or below (OR 1.251, 95% CI 1.068-1.465, p=0.006) and less likely to eat more vegetables (OR 0.927, 95% CI 0.863-0.996, p=0.037) than the normal-tHcy participants. In women, participants with Hhcy were more likely to have longer sleeping time (>9h/d) (OR 1.677, 95% CI 1.292-2.177, p<0.001), low physical activity (OR 1.721, 95% CI 1.197-2.475, p=0.044) and increased diet score (OR 1.126, 95% CI 1.007-1.259, p=0.037) and less likely to be current drinkers (OR 0.488, 95% CI 0.297-0.802, p=0.005) than the normal-tHcy participants.

CONCLUSION

Our study revealed that physical activity and current drinking status were not significantly associated with Hhcy in males, but inversely associated in females. In both genders, current smoking status and dietary habits were significantly associated with Hhcy. Our study supports existing recommendations for Chinese to maintain a physically active behaviors and healthy lifestyle habits.

Effect of physical activity on levels of homocysteine, folate, and vitamin B12 in the elderly

OBJECTIVES

Homocysteine (Hcy) has emerged as a risk factor for cardiovascular diseases (CVD). However the relationship of physical activity (PA) with Hcy levels in the elderly is controversial. Accordingly, the current study examined the effect of low and high participation in PA on serum Hcy in young (n = 77; 18-50 years) and old (n = 207; > 65 years) males (n = 141) and females (n = 142).

METHODS

Level of PA was obtained in a 1-to-1 interview and participants divided into low and high groups. Serum Hcy, folate, and vitamin B12 were obtained after 12 hour fast drawn by venipuncture.

RESULTS

Levels of Hcy correlated with folate (r = -0. 5; p = 0.000) and vitamin B12 (r = -0.3; p = 0.000). The ANOVA revealed a main effect of PA for Hcy (p = 0.04) but not for folate (p = 0.2) and vitamin B12 (p = 0.2). Main effects were found also of age for Hcy (p = 0.000) and folate (p = 0.005) as well as of gender for Hcy (p = 0.000) and vitamin B12 (p = 0.000). Subsequent ANCOVA showed lower levels of Hcy in the participants with greater versus lower PA even after controlling for B12 vitamin.

CONCLUSION

These results confirm the importance of the vitamins for regulating Hcy levels. Additionally, the data suggests that PA affects Hcy levels without affecting and independent of B vitamins in the elderly.

A single session of exhaustive exercise markedly decreases circulating levels of guanidinoacetic acid in healthy men and women

We evaluated the effects of exercise on circulating concentrations of guanidinoacetic acid (GAA) and creatine in 23 healthy volunteers subjected to running to exhaustion and free-weight bench-press to volitional failure. Blood was taken before and following each exercise session. Running induced a significant decrease in serum GAA by 20.1% (P < 0.001), while free-weight exercise reduced GAA by 11.7% (P < 0.001), suggesting the possible use of serum GAA as a novel biomarker of exhaustion.

The Effects of Acute Exercise and Exercise Training on Plasma Homocysteine: A Meta-Analysis

Background

Although studies have demonstrated that physical exercise alters homocysteine levels in the blood, meta-analyses of the effects of acute exercise and exercise training on homocysteine blood concentration have not been performed, especially regarding the duration and intensity of exercise, which could affect homocysteine levels differently.

Objective

The aim of this meta-analysis was to ascertain the effects of acute exercise and exercise training on homocysteine levels in the blood.

Method

A review was conducted according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses using the online databases PubMed, SPORTDiscus, and SciELO to identify relevant studies published through June 2015. Review Manager was used to calculate the effect size of acute exercise and exercise training using the change in Hcy plasmaserum concentration from baseline to post-acute exercise and trained vs. sedentary control groups, respectively. Weighted mean differences were calculated using random effect models.

Results

Given the abundance of studies, acute exercise trials were divided into two subgroups according to exercise volume and intensity, whereas the effects of exercise training were analyzed together. Overall, 22 studies with a total of 520 participants indicated increased plasma homocysteine concentration after acute exercise (1.18 μmol/L, 95% CI: 0.71 to 1.65, p < .01). Results of a subgroup analysis indicated that either long-term exercise of low-to-moderate intensity (1.39 μmol/L, 95% CI: 0.9 to 1.89, p < .01) or short-term exercise of high intensity (0.83 μmol/L, 95% CI: 0.19 to 1.40, p < .01) elevated homocysteine levels in the blood. Increased homocysteine induced by exercise was significantly associated with volume of exercise, but not intensity. By contrast, resistance training reduced plasma homocysteine concentration (-1.53 μmol/L, 95% CI: -2.77 to -0.28, p = .02), though aerobic training did not. The cumulative results of the seven studies with a total of 230 participants in exercise training analysis did not demonstrate a significant impact on homocysteine levels in the blood (-0.56 μmol/L, 95% CI: -1.61 to 0.50, p = .23).

Conclusions

Current evidence demonstrates that acute exercise increases homocysteine levels in the blood independent of exercise duration and intensity. Resistance, but not aerobic training decreases plasma homocysteine levels.

The role of dietary creatine

The daily requirement of a 70-kg male for creatine is about 2 g; up to half of this may be obtained from a typical omnivorous diet, with the remainder being synthesized in the body Creatine is a carninutrient, which means that it is only available to adults via animal foodstuffs, principally skeletal muscle, or via supplements. Infants receive creatine in mother's milk or in milk-based formulas. Vegans and infants fed on soy-based formulas receive no dietary creatine. Plasma and muscle creatine levels are usually somewhat lower in vegetarians than in omnivores. Human intake of creatine was probably much higher in Paleolithic times than today; some groups with extreme diets, such as Greenland and Alaskan Inuit, ingest much more than is currently typical. Creatine is synthesized from three amino acids: arginine, glycine and methionine (as S-adenosylmethionine). Humans can synthesize sufficient creatine for normal function unless they have an inborn error in a creatine-synthetic enzyme or a problem with the supply of substrate amino acids. Carnivorous animals, such as lions and wolves, ingest much larger amounts of creatine than humans would. The gastrointestinal tract and the liver are exposed to dietary creatine in higher concentrations before it is assimilated by other tissues. In this regard, our observations that creatine supplementation can prevent hepatic steatosis (Deminice et al. J Nutr 141:1799-1804, 2011) in a rodent model may be a function of the route of dietary assimilation. Creatine supplementation has also been reported to improve the intestinal barrier function of the rodent suffering from inflammatory bowel disease.

Dose-response effects of oral guanidinoacetic acid on serum creatine, homocysteine and B vitamins levels

PURPOSE

Guanidinoacetic acid (GAA) is an intermediate in the biosynthesis of creatine (Cr), yet its use in human nutrition is limited due to a lack of a clear understanding of its' dose-response effect. Thus, the purpose of this study was to investigate the effect of three different dosages of GAA (1.2, 2.4 and 4.8 g/day) administered for 6 weeks on serum and urinary variables related to GAA metabolism.

METHODS

Forty-eight healthy volunteers participated in the randomized, placebo-controlled, double-blind, repeated-measure study. At baseline, after 1, 2, 4 and 6 weeks, participants provided both fasting blood samples and 24-h urine.

RESULTS

GAA intervention significantly increased serum and urinary GAA, Cr and creatinine as compared to placebo (P < 0.05). Differences were found for serum GAA and Cr responses between the three GAA dosages, with high-dose GAA resulting in a greater increase (P < 0.05) in the plasma concentration of both variables as compared to other GAA dosages. In GAA groups, fasting plasma total homocysteine (T-Hcy) increased by 3.5 μmol/L on average at post-administration, yet no dose-response differences were found between trials. Serum B vitamins were not affected by either placebo or GAA intervention (P > 0.05).

CONCLUSION

Results indicate that low-to-high dosages of exogenous GAA can increase serum concentrations of Cr and T-Hcy while not depleting the B vitamins pool available for remethylation of homocysteine.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, identification number NCT01133899.

Effect of folic acid supplementation on homocysteine concentration and association with training in handball players

Background

Strenuous physical activity can alter the status of folic acid, a vitamin directly associated with homocysteine (Hcy); alterations in this nutrient are a risk factor for cardiovascular disease. Handball players are a population at risk for nutrient deficiency because of poor dietary habits.

Objective

The aims of this study were to evaluate nutritional status for macronutrients and folic acid in members of a high-performance handball team, and determine the effect of a nutritional intervention with folic acid supplementation and education.

Design

A total of 14 high-performance handball players were monitored by recording training time, training intensity (according to three levels of residual heart rate (RHR): <60%, 60%–80% and >80%), and subjective perceived exertion (RPE) during a 4-month training period. Nutritional, laboratory and physical activity variables were recorded at baseline (Week 0), after 2 months of dietary supplementation with 200 μg folic acid (50% of the recommended daily allowance) (Week 8) and after 2 months without supplementation (Week 16). We compared training load and analyzed changes in plasma concentrations of Hcy before and after the intervention.

Results

Bivariate analysis showed a significant negative correlation (P < 0.01) between Hcy and folic acid concentrations (r = −0.84) at Week 8, reflecting a significant change in Hcy concentration (P < 0.05) as a result of hyperhomocysteinemia following the accumulation of high training loads. At Week 16 we observed a significant negative correlation (P < 0.01) between Hcy concentration and training time with an RHR <60%, indicating that aerobic exercise avoided abrupt changes in Hcy and may thus reduce the risk of cardiovascular accidents in high-performance athletes.

Conclusion

Integral monitoring and education are needed for practitioners of handball sports to record their folic acid status, a factor that directly affects Hcy metabolism. Folic acid supplementation may protect athletes against alterations that can lead to cardiovascular events related to exertion during competition.

Transient increase in homocysteine but not hyperhomocysteinemia during acute exercise at different intensities in sedentary individuals

Considering that hyperhomocysteinemia is an independent risk factor for cardiovascular disease, the purpose of this study was to determine the kinetics of serum homocysteine (tHcy) and the vitamins involved in its metabolism (folates, B₁₂, and B₆) in response to acute exercise at different intensities. Eight sedentary males (18–27 yr) took part in the study. Subjects were required to complete two isocaloric (400 kcal) acute exercise trials on separate occasions at 40% (low intensity, LI) and 80% VO_2peak (high intensity, HI). Blood samples were drawn at different points before (pre4 and pre0 h), during (exer10, exer20, exer30, exer45, and exer60 min), and after exercise (post0, post3, and post19 h). Dietary, genetic, and lifestyle factors were controlled. Maximum tHcy occurred during exercise, both at LI (8.6 (8.0–10.1) µmol/L, 9.3% increase from pre0) and HI (9.4 (8.2–10.6) µmol/L, 25.7% increase from pre0), coinciding with an accumulated energy expenditure independent of the exercise intensity. From this point onwards tHcy declined until the cessation of exercise and continued descending. At post19, tHcy was not different from pre-exercise values. No values of hyperhomocysteinemia were observed at any sampling point and intensity. In conclusion, acute exercise in sedentary individuals, even at HI, shows no negative effect on tHcy when at least 400 kcal are spent during exercise and the nutritional status for folate, B₁₂, and B₆ is adequate, since no hyperhomocysteinemia has been observed and basal concentrations were recovered in less than 24 h. This could be relevant for further informing healthy exercise recommendations.

Serum homocysteine and physical exercise in patients with Parkinson's disease

BACKGROUND

Hyperhomocysteinemia is a major risk factor for cerebral and peripheral vascular diseases, as well as cortical and hippocampal injury, including an increased risk of dementia and cognitive impairment. Elevated serum homocysteine (Hcy) concentrations are common in patients with Parkinson's disease (PD) who have been treated with levodopa; however, physical exercises can help reduce Hcy concentrations. The aim of the present study was to compare serum Hcy levels in patients with PD who partook in regular physical exercises, sedentary PD patients, and healthy controls.

METHODS

Sixty individuals were enrolled in the present study across three groups: (i) 17 patients who did not partake of any type of exercise; (ii) 24 PD patients who exercised regularly; and (iii) 19 healthy individuals who did not exercise regularly. All participants were evaluated by Hoehn and Yahr scale, the Unified Parkinson's Disease Rating Scale (UPDRS) and Schwab and England scale (measure daily functionality). The serum levels of Hcy were analyzed by blood samples collected of each participant. An analysis of variance and a Tukey's post hoc test were applied to compare and to verify differences between groups. Pearson's correlation and stepwise multiple regression analyses were used to consider the association between several variables.

RESULTS

Mean plasma Hcy concentrations in individuals who exercised regularly were similar to those in the healthy controls and significantly lower than those in the group that did not exercise at all (P= 0.000). In addition, patients who did not exercise were receiving significantly higher doses of levodopa than those patients who exercised regularly (P= 0.001). A positive relationship between levodopa dose and Hcy concentrations (R(2) = 0.27; P= 0.03) was observed in patients who did not exercise, but not in those patients who exercised regularly (R(2) = 0.023; P= 0.15).

CONCLUSIONS

The results of the present study suggest that, even with regular levodopa therapy, Hcy concentrations in PD patients who exercise regularly are significantly lower than in patients who do not exercise and are similar Hcy concentrations in healthy controls.

Creatine supplementation reduces increased homocysteine concentration induced by acute exercise in rats

The aim of this study was to evaluate the effect of creatine supplementation on homocysteine (Hcy) metabolism after acute aerobic and anaerobic exercise. A total of 112 Wistar rats were divided into four groups: aerobic exercise (A), aerobic exercise plus creatine supplementation (ACr), anaerobic exercise (An), and anaerobic exercise plus creatine-supplemented (AnCr). Creatine supplementation consisted of the addition of 2% creatine monohydrate to the diet. After 28 days, the rats performed an acute moderate aerobic exercise bout (1 h swimming with 4% of total body weight load) or an acute intense anaerobic exercise bout (6 × 30-s vertical jumps into the water with a 30-s rest between jumps, with 50% of total body weight load). The animals were killed before (pre) and at 0, 2, and 6 h (n = 8) after acute exercise. Plasma Hcy concentration increased significantly (P < 0.05) up to 2 h after anaerobic exercise (An group: pre 8.7 ± 1.2, 0 h 13.2 ± 2.3, 2 h 13.5 ± 4.2, and 6 h 12.1 ± 2.2, μmol/l). The same did not occur in acute aerobic exercised animals. Nevertheless, creatine supplementation significant decreased (P < 0.05) homocysteine concentration independent of exercise intensity (AnCr group: pre 17%, 0 h 80%, 2 h 107%, and 6 h 48%; ACr group: pre 17%, 0 h 19%, 2 h 28%, and 6 h 27%). Increased S-adenosylhomocysteine was also found in the An group. In conclusion, acute intense anaerobic exercise increased plasma Hcy concentration. On the other hand, creatine supplementation decreased plasma Hcy independent of exercise intensity.

Interactions between genetic variants of folate metabolism genes and lifestyle affect plasma homocysteine concentrations in the Boston Puerto Rican population

OBJECTIVE

To investigate genetic and lifestyle factors and their interactions on plasma homocysteine (Hcy) concentrations in the Boston Puerto Rican population.

DESIGN

Cross-sectional study. Plasma concentrations of Hcy, folate, vitamin B12 and pyridoxal phosphate were measured, and genetic polymorphisms were determined. Data on lifestyle factors were collected in interviews.

SETTING

A population survey of health and nutritional measures.

SUBJECTS

A total of 994 Puerto Rican men and women residing in the Boston metropolitan area.

RESULTS

Smoking status was positively associated with plasma Hcy. Genetic polymorphisms MTHFR 677C→T, FOLH1 1561C→T, FOLH1 rs647370 and PCFT 928A→G interacted significantly with smoking for Hcy. MTHFR 1298A→C (P = 0·040) and PCFT 928A→G (P = 0·002) displayed significant interactions with alcohol intake in determining plasma Hcy. Subjects with PCFT 928GG genotype had significantly higher plasma Hcy concentrations compared with carriers of the A allele (AA+AG; P = 0·030) among non-drinking subjects. When consuming alcohol, GG subjects had lower plasma Hcy levels compared with AA+AG subjects. Physical activity interacted significantly with MTR 2756A→G in determining plasma Hcy (P for interaction = 0·002). Smoking interacted with physical activity for plasma Hcy (P for interaction = 0·023).

CONCLUSIONS

Smoking and drinking were associated plasma Hcy concentrations. Genetic variants involved in folate metabolism further modify the effects of lifestyle on plasma Hcy.

Plasma vitamins, amino acids, and renal function in postexercise hyperhomocysteinemia

Several studies have assessed the effect of the physical activity on plasma homocysteine (Hcy) concentrations, although the findings have been contradictory, and the exact mechanism by which plasma Hcy concentrations varied after an acute intense exercise remains unknown.

PURPOSE

We studied the effect of different acute aerobic intense exercises on plasma, reduced, and total Hcy (rHcy, tHcy) and cysteine (rCys, tCys) and on its metabolically related vitamins and amino acids. Parallel effects on renal function were assessed by plasma creatinine.

METHODS

Fifteen cyclists and 14 kayakers were examined before and 30 +/- 5 min after a specific test to exhaustion during a low-intensity training period.

RESULTS

After a bout of specific exercise, the concentrations of aminothiols were increased regardless of the group considered. Plasma concentrations were higher than baseline values in tHcy (17.7 +/- 1.5%; P < 0.001), rHcy (10.6 +/- 1.6%; P < 0.001), tCys (9.9 +/- 1.6%; P < 0.001), and rCys (7.6 +/- 2.2%; P < 0.01). Both groups showed significant elevations of pyridoxal-5'-phosphate (PLP; P < 0.01), vitamin B12 (P < 0.001), and creatinine concentrations (P < 0.001) after acute exercises, but no changes were seen in folate. Changes in plasma aminothiols after exercise did not reach significant correlation with changes in free amino acids or baseline vitamins, but significant and positive correlations were observed with changes in plasma PLP, vitamin B12, and creatinine concentrations, when the pooled data were considered.

CONCLUSIONS

Our results show that higher plasma concentrations of tHcy after an acute intense exercise are associated to higher concentrations of rHcy, and this effect is independent of the type of exercise, vitamin status, or amino acid metabolic stress but could be related to potential changes in the renal function.