The exercise redox paradigm in the Down's syndrome: improvements in motor function and increases in blood oxidative status in young adults

Effects of therapeutic exercise on the motor function of adults with Down syndrome: a systematic review and meta-analysis

Therapeutic exercise exerts positive effects by mitigating or reducing the motor or cognitive changes that people with Down syndrome undergo throughout their life. There are no updated systematic reviews that integrate the evidence available in a way that facilitates decision-making for physical rehabilitation teams. This study therefore aimed to consolidate the information available and compare the effects of different types of physical exercise on the motor function of adults with DS. We conducted a systematic review and meta-analysis of randomized clinical trials and quasi-experimental studies. The literature search was performed between January 2023 and February 2023 using the PubMed, SCIELO, Epistemonikos, and Lilacs databases. Studies were selected according to pre-determined inclusion and exclusion criteria. The risk-of-bias assessment was performed using the risk-of-bias rating tool for randomized clinical trial (RoB) and the risk of bias of non-randomized comparative studies was assessed using the risk of bias in non-randomized studies of interventions (ROBINS-I) tool. Risk-of-bias assessment and meta-analyses were performed using the RevMan software package. Sixteen studies met the eligibility criteria for the qualitative synthesis and 4 were included in the meta-analyses. Combined exercise significantly increased muscle strength both in the upper limbs (SMD = 0.74 [95% CI 0.25-1.22]) and lower limbs (SMD = 0.56[95% CI 0.08-1.04]). Aerobic exercise improved spatiotemporal gait parameters. Aerobic exercise showed significant improvements in dynamic balance while combined exercise significantly increased dynamic and static balance. The certainty of the evidence was low to moderate for all outcomes. There was low and moderate certainty of evidence for the outcomes proposed in this review. However, therapeutic exercise could be effective in improving muscle strength and gait functionality.

Effectiveness of exergames programme to modify body composition and health-related physical fitness in adolescents with down syndrome after COVID-19 quarantine

AIMS

to determine the effect of a 20-week exergame program on different indicators of body composition and components of health-related physical fitness in adolescents with Down syndrome. Methods and Procedures Outcomes: 49 adolescents (19 female and 30 males; average age, 14.19 ± 2.06 years) with Down syndrome were recruited and randomized to two groups (control group vs. intervention group). Adolescents allocated in the control group carried out a physical activity program three times a week for 20 weeks meanwhile adolescents allocated in the exercise group performed an exergame program three times a week for 20 weeks.

RESULTS

The exercise group had significant improvements in all health-related physical fitness variables and there is an improvement in some body composition variables (p < 0.05).

CONCLUSIONS AND IMPLICATIONS

20 week exergame program consisting of 3 sessions of 60 minutes is able to improve levels of body composition and health-related physical fitness in adolescents with Down syndrome.Highlights Research in body composition and health-related physical fitness of people with Down syndrome has revealed that an exergame programme increases levels of health-related physical fitness in adolescents with Down syndromeAn exergame programme can improve differences in markers of body composition between the control group and the intervention groupThe intervention group that performed the exergame programme showed increases in health-related physical fitness levels after 20 weeks of intervention.The control group that performed a based on developing motor behaviour programme did not show differences in body composition or health-related physical fitness after 20 weeks of intervention.

Health Outcomes of Physical Activity Interventions in Adults With Down Syndrome: A Systematic Review

This systematic review examined whether physical activity interventions improve health outcomes in adults with Down syndrome (DS). We searched PubMed, APA PsycInfo, SPORTDiscus, APA PsycARTICLES, and Psychology and Behavioral Sciences Collection using keywords related to DS and physical activity. We included 35 studies published in English since January 1, 1990. Modes of exercise training programs included aerobic exercise, strength training, combined aerobic and strength training, aquatic, sport and gaming, and aerobic and strength exercise interventions combined with health education. The evidence base indicates that aerobic and strength exercise training improve physical fitness variables including maximal oxygen uptake, maximal heart rate, upper and lower body strength, body weight, and body fat percentage. Sport and gaming interventions improve functional mobility, work task performance, and sport skill performance. We concluded that adults with DS can accrue health benefits from properly designed physical activity and exercise interventions.

Dose caffeinated energy drink is a consideration issue for endurance performance

Caffeinated energy drinks are commonly taken to improve exercise performance, but there are few studies on the influence of different doses on an athlete’s performance. We conducted a double-blind, randomized, counter-balanced, and crossover research study to examine the effects of low caffeinated energy drink (Low ED) or high caffeinated energy drink (High ED) supplement on the performance, haematological response, and oxidative stress in triathletes. Twelve male participants underwent three testing sessions separated by weekly intervals, consisting of sprint triathlon training (0.75 km swim, 20 km cycle, and 5 km run). Before and during the trials, participants were randomly provided with either placebo (PLA) group, Low ED group, or High ED group. Exercise performance in the High ED group decreased significantly compared with the PLA and Low ED groups (p < 0.05). However, participants in the Low ED group also experienced an improved performance (p = 0.054). Analysis of variance revealed no differences among the three groups in cortisol and testosterone levels, or the Borg Rating of Perceived Exertion score (p > 0.5). Furthermore, superoxide dismutase (SOD) was reduced with exercise and were lowest in the High ED group. However, compared with PLA, a significant decrease of thiobarbituric acid reactive substances (TBARS) was observed in Low ED and High ED groups (p < 0.05). This indicates that caffeinated energy drink consumption may improve performance and reduce oxidative stress in sprint triathlon athletes. However, individual differences should be considered when supplementing with caffeinated energy drinks to decrease side effects.

Resistance training and Down Syndrome: A narrative review on considerations for exercise prescription and safety

The current manuscript reviews the literature on the health effects of resistance training (RT) for individuals with Down syndrome (DS), focusing on this training modality’s methodology, application, and safety. The literature has mentioned that early aging in this population is associated with loss of muscle strength, lower lean and bone mass, and increased obesity. It is necessary to propose non-pharmacological measures for prevention and health promotion. Thus, this review suggests a current research-based RT guide for individuals with DS. This review is divided into three sections: Section 2 briefly reviews DS and the effects on structural and functional decline and how exercise and physical activity can influence health aspects in this population; Section 3 summarizes the evidence for RT prescription; Section 4 briefly reviews the health and potential benefits of RT in individuals with DS. The findings from this review suggest that most individuals with DS should engage in moderate-intensity RT at least 2 days a week and perform RT on the major muscle groups and include balance training. The RT program should be modified and adapted according to individuals’ characteristics and limitations. RT promotes positive, health-related benefits such as increasing strength, improving body composition, improving functional capacity and balance, reducing inflammatory status and oxidative stress, and improving the immune system. The RT protocols summarized in this current review provide guidance, critical conclusions, and novel research settings, which could be useful to coaches, clinicians, and researchers to effectively design RT program for individuals with DS.

Peripheral Oxidation Markers in Down Syndrome Patients: The Better and the Worse

Oxidative stress plays an important role in Down syndrome (DS) pathology since the gene dose effect leads to abnormal levels of certain enzymes and metabolites. In this review, we focused on relatively easy-to-obtain, peripheral markers of oxidative stress and inflammation, in order to compare the levels of these markers in DS patients and chromosomally healthy persons. Studies taking into account age- and sex-matched control groups were of particular interest in this context. We analyzed the factors that influence the levels of said markers in both groups (i.e., the usefulness of the markers), including the age of DS patients, occurrence of regular trisomy 21 or mosaicism, physical activity of patients, and the onset of Alzheimer's disease in DS. This paper was conceived as a handbook-to help for selecting suitable, easy-to-obtain markers for monitoring of the health status of DS patients (e.g., in nutritional studies and during dietary supplementation).

Meta-analysis of metabolites involved in bioenergetic pathways reveals a pseudohypoxic state in Down syndrome

Clinical observations and preclinical studies both suggest that Down syndrome (DS) may be associated with significant metabolic and bioenergetic alterations. However, the relevant scientific literature has not yet been systematically reviewed. The aim of the current study was to conduct a meta-analysis of metabolites involved in bioenergetics pathways in DS to conclusively determine the difference between DS and control subjects. We discuss these findings and their potential relevance in the context of pathogenesis and experimental therapy of DS. Articles published before July 1, 2020, were identified by using the search terms “Down syndrome” and “metabolite name” or “trisomy 21” and “metabolite name”. Moreover, DS-related metabolomics studies and bioenergetics literature were also reviewed. 41 published reports and associated databases were identified, from which the descriptive information and the relevant metabolomic parameters were extracted and analyzed. Mixed effect model revealed the following changes in DS: significantly decreased ATP, CoQ10, homocysteine, serine, arginine and tyrosine; slightly decreased ADP; significantly increased uric acid, succinate, lactate and cysteine; slightly increased phosphate, pyruvate and citrate. However, the concentrations of AMP, 2,3-diphosphoglycerate, glucose, and glutamine were comparable in the DS vs. control populations. We conclude that cells of subjects with DS are in a pseudo-hypoxic state: the cellular metabolic and bio-energetic mechanisms exhibit pathophysiological alterations that resemble the cellular responses associated with hypoxia, even though the supply of the cells with oxygen is not disrupted. This fundamental alteration may be, at least in part, responsible for a variety of functional deficits associated with DS, including reduced exercise difference, impaired neurocognitive status and neurodegeneration.

The health benefits of exercise therapy for patients with Down syndrome: A systematic review

Background

Many patients with Down syndrome (PWDS) have poor cardiometabolic risk profiles, aerobic capacities and weak hypotonic muscles, primarily because of physical inactivity and poor diet.

Objectives

This study discusses the benefits of exercise therapy on body composition, aerobic capacity, muscle strength, proprioception and cardiometabolic profiles of PWDS.

Methods

A literature review using the Crossref metadatabase, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), focusing on the period 2007-2018, was undertaken. Each record was judged adopting the modified Downs and Black Appraisal Scale. The literature investigation identified 15 701 records. Records were excluded if they were published before 2007, pertained to the impact of exercise on intellectual disabilities beyond Down syndrome or the impact of medical, pharmaceutical, nutrition and psychological interventions among PWDS and were published in languages besides English. Nineteen articles were synthesised into this commentary.

Results

PWDS have a heightened cardiometabolic risk profile and high oxidative stress associated with elevated insulin resistance, poor insulin sensitivity, atherosclerosis and hypertension. PWDS have low aerobic capacity (VO_2max), peak heart rates, muscle strength, agility and balance. Regular physical activity is beneficial to improve their VO_2max and muscle strength. Moreover, regular physical activity reduces lipid peroxidation and arterial cell wall damage, the pathogenesis of atheroma is limited.

Conclusion

Exercise therapy compliance seems to have a positive impact on the cardiometabolic risk profile, muscle strength and aerobic work capacity of PWDS. Nonetheless, additional vigorous experimental investigations are necessary to better understand the effect of exercise therapy on the aerobic, strength, proprioception and cardiometabolic risk profile of PWDS.

The Role of PGC-1α/UCP2 Signaling in the Beneficial Effects of Physical Exercise on the Brain

In understanding the pathology of neurological diseases, the role played by brain energy metabolism is gaining prominence. Animal models have demonstrated that regular physical exercise improves brain energy metabolism while also providing antidepressant, anxiolytic, antioxidant and neuroprotective functions. This review summarizes the latest evidence on the roles played by peroxisome proliferator-activated receptor gamma (PPAR-γ) coactivator 1-alpha (PGC-1α) and mitochondrial uncoupling protein (UCP) in this scenario. The beneficial effects of exercise seem to depend on crosstalk between muscles and nervous tissue through the increased release of muscle irisin during exercise.

What effect does regular exercise have on oxidative stress in people with Down syndrome? A systematic review with meta-analyses

OBJECTIVE

What effect does regular exercise have on oxidative stress in people with Down syndrome?

DESIGN

Systematic review with meta-analyses.

METHODS

A systematic review with meta-analyses was conducted. Six databases were searched from inception until August 2017. Studies where included if participants with Down syndrome (any age) had completed an exercise program of at least 6 weeks duration and at least one biomarker measured the generation or removal of reactive oxidative species. Data were extracted using a customised form. Risk of bias was assessed using the Cochrane Collaboration's Risk of Bias assessment tool. Effect sizes were calculated and meta-analyses completed for clinically homogeneous data using a random effects model.

RESULTS

Seven studies (11 articles) involving 144 inactive participants investigated the effect of moderate intensity aerobic exercise. No pattern emerged for how most biomarkers responded with non-significant pooled effect sizes and high levels of heterogeneity observed. The exception was catalase which increased significantly after exercise (standardised mean difference 0.39, 95%CI 0.04-0.75; I² 15%). Available studies were at high risk of bias. Two of five studies that measured more than one biomarker reported a decrease in oxidative stress with increased antioxidant activity after exercise but the other three (including one small randomised controlled trial) reported increased oxidative stress with variable change in antioxidant activity.

CONCLUSIONS

There remains uncertainty about the effect of exercise on oxidative stress in people with Down syndrome.

REVIEW REGISTRATION

PROSPERO CRD42016048492.

The effect of exercise intervention on daily life activities and social participation in individuals with Down syndrome: A systematic review

BACKGROUND

Few systematic reviews have looked at the effect of exercise intervention on activities of daily living and social participation in individuals with Down syndrome (DS) across the lifespan.

AIMS

To evaluate the research on the effectiveness of exercise intervention on daily life activities and participation in individuals with DS.

METHODS AND PROCEDURES

Studies are from six electronic databases (CINHAL, Cochrane, ERIC, PEDro, PubMed, and PsycINFO) from 1987 to 2016. Nineteen studies met inclusion criteria. American Academy for Cerebral Palsy and Developmental Medicine (AACPDM) levels of evidence and an Intervention Clinical Appraisal Form were used to independently assess study quality and outcome measures coded using the International Classification of Functioning, Disability, and Health (ICF).

OUTCOMES AND RESULTS

There were 525 participants, age range, 3-65.5 years. The quality of the studies ranges from AACPDM Level I-IV and Intervention Clinical Appraisal Form scores of 4 to 10. A meta analysis was not conducted due to heterogenity of studies.

CONCLUSIONS AND IMPLICATIONS

Exercise intervention was supported for both daily life activities and participation. Rigorous research studies are needed across the lifespan using objective outcome measures for ICF levels.

THE EFFECT OF CAFFEINE SUPPLEMENTATION ON TRAINED INDIVIDUALS SUBJECTED TO MAXIMAL TREADMILL TEST

Background:

Intense physical training increases oxidative stress and inflammation, resulting into muscle and cellular damage. The aim of this study was to analyze the effect of caffeine supplementation on trained young individuals subjected to two treadmill maximal tests.

Materials and Methods:

It was a double-blind and crossover study comprising 24 active individuals within the age group 18-30 years. The comparisons were conducted: the effect of exercise (week 1 x 2) and caffeine intake (GC x GP) on thiobarbituric acid (TBARS), interleukin 6 (IL-6), interleukin 10 (IL-10) and superoxide dismutase (SOD) variables during pre-exercise time (30 min. after caffeine or placebo intake) and post-exercise (5 min after treadmill test).

Results:

The comparison between weeks 1 and 2 showed increase in the first week, in the following items: TBARS, IL-6 and IL-10 in the GC and GP groups. The comparison within the same week showed that GC individuals presented lower post-exercise TBARS values in the first and second weeks; IL- 6 presented higher post-exercise values in the GC group in both weeks. The paired analysis comparing pre- and post-exercise, with and without caffeine showed that IL-6 presented higher post-exercise values in the GC group.

Conclusion:

Caffeine used by athletes can decrease oxidative stress. The increased IL-6 suggest that this ergogenic supplement may stimulate muscle hypertrophy, since IL-6 has myokine effect. However, the caffeine effect on IL-6 level and muscle hypertrophy increase should be better investigated in future studies.

Physical Training Regulates Mitochondrial Parameters and Neuroinflammatory Mechanisms in an Experimental Model of Parkinson's Disease

This study aimed to evaluate the effects of two different protocols for physical exercise (strength and aerobic training) on mitochondrial and inflammatory parameters in the 6-OHDA experimental model of Parkinson's disease. Six experimental groups were used (n = 12 per group): untrained + vehicle (Sham), strength training + vehicle (STR), treadmill training + vehicle (TTR), untrained + 6-OHDA (U + 6-OHDA), strength training + 6-OHDA (STR + 6-OHDA), and treadmill training + 6-OHDA (TTR + 6-OHDA). The mice were subjected to strength or treadmill training for 8 weeks. PD was induced via striatal injection of 6-OHDA 24 h after the last exercise session. Mice were euthanized by cervical dislocation and the striatum and hippocampus were homogenized to determine levels of tyrosine hydroxylase (TH), nuclear factor kappa B (NF-κB) p65, and sirtuin 1 (Sirt1) by western blot; tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-17, interferon-γ (IFN-γ), and transforming growth factor β1 (TGF-β1) levels by ELISA; NO content; and complex I (CI) activity. STR + 6-OHDA mice had higher TH levels and CI activity and lower NF-κB p65 and IFN-γ levels in the striatum compared to U + 6-OHDA mice, while TTR + 6-OHDA mice had higher Sirt1 levels and CI activity in both the striatum and the hippocampus, compared to U + 6-OHDA mice. Strength training increased CI activity and TH and Sirt1 levels and reduced NO, NF-κB p65, TNF-α, IFN-γ, IL-1β, and TGF-β1 levels in 6-OHDA mice, while treadmill exercise increased CI activity and NO, TH, and Sirt1 levels and reduced NF-κB p65, TNF-α, IFN-γ, and IL-1β levels. Our results demonstrated that both treadmill training and strength training promote neuroprotection, possibly by stimulating Sirt1 activity, which may in turn regulate both mitochondrial function and neuroinflammation via deacetylation of NF-κB p65. Changes in nitric oxide levels may also be a mechanism by which 6-OHDA-induced inflammation is controlled.

Down syndrome and dementia: a randomized, controlled trial of antioxidant supplementation

Individuals with Down syndrome over age 40 years are at risk for developing dementia of the Alzheimer type and have evidence for chronic oxidative stress. There is a paucity of treatment trials for dementia in Down syndrome in comparison to Alzheimer disease in the general (non-Down syndrome) population. This 2-year randomized, double-blind, placebo-controlled trial assessed whether daily oral antioxidant supplementation (900 IU of alpha-tocopherol, 200 mg of ascorbic acid and 600 mg of alpha-lipoic acid) was effective, safe and tolerable for 53 individuals with Down syndrome and dementia. The outcome measures comprised a battery of neuropsychological assessments administered at baseline and every 6 months. Compared to the placebo group, those individuals receiving the antioxidant supplement showed neither an improvement in cognitive functioning nor a stabilization of cognitive decline. Mean plasma levels of alpha-tocopherol increased ~2-fold in the treatment group and were consistently higher than the placebo group over the treatment period. Pill counts indicated good compliance with the regimen. No serious adverse events attributed to the treatment were noted. We conclude that antioxidant supplementation is safe, though ineffective as a treatment for dementia in individuals with Down syndrome and Alzheimer type dementia. Our findings are similar to studies of antioxidant supplementation in Alzheimer disease in the general population. The feasibility of carrying out a clinical trial for dementia in Down syndrome is demonstrated.

When the air hits your brain: cerebral autoregulation of brain oxygenation during aerobic exercise allows transient hyperoxygenation: case report

OBJECTIVE

Cerebral autoregulation maintains a relatively stable cerebral blood flow over a range of perfusion pressures. During exercise, regional cerebral blood flow may be elevated in particular areas of the brain. This case report presents the impact of aerobic exercise on intracranially measured pressure and brain tissue oxygenation in an adult human.

CLINCIAL PRESENTATION

A 30-year-old man with idiopathic intracranial hypertension treated with cerebrospinal fluid diversion was monitored with a Licox intracranial brain oxygen and pressure monitor (Integra NeuroSciences Corporation, Plainsboro, New Jersey) for refractory nonpostural headaches exacerbated after exercise. He performed trials of running and bicycling to provoke his headaches. The patient's mean intracranial pressure remained stable during exercise despite elevated cerebral perfusion pressures. Regional cerebral oxygen tension levels were strictly regulated to a level of approximately 39 mm Hg during steady state aerobic exercise, with transient increases up to 90 mm Hg at the onset and termination of activity.

CONCLUSION

Our results suggest that cerebral autoregulation appears to maintain constant cerebral oxygen tension during exercise. Further, we note transient cerebral hyperoxygenation at the onset of exercise as autoregulation "turns on" and at the termination of exercise. We present a quantitative interpretation of the post-exercise hyperoxygenation phase based on Fick's principle. We are the first to demonstrate cortical hyperoxygenation in a human breathing natural air without oxygen supplementation.

Aerobic exercise training programmes for improving physical and psychosocial health in adults with Down syndrome

BACKGROUND

Although physical fitness has been suggested to improve physical and psychosocial health for a variety of population profiles, there is a lack of information about the safety and effectiveness of aerobic exercise for adults with Down syndrome.

OBJECTIVES

To evaluate the effectiveness and safety of aerobic exercise training programmes for physiological and psychosocial outcomes in adults with Down syndrome.

SEARCH STRATEGY

The following electronic databases were searched: The Cochrane Central Register of Controlled Trials (CENTRAL) (2009, Issue 1); MEDLINE (1966 to August 2009); EMBASE (1980 to August 2009); CINAHL (1982 to August 2009); LILACS (1982 to August 2009); PsycINFO (1887 to August 2009); ERIC (1966 to August 2009); Current Controlled Trials (August 2009); and Campbell Collaboration's Social, Psychological, Educational and Criminological Register (C2- SPECTR) (to August 2009). Information about ongoing clinical trials was sought by searching ClinicalTrials.gov (http://clinicaltrials.gov) (accessed August 2009), and the National Research Register (NRR) (2009 Issue 1).

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials using supervised aerobic exercise training programmes with behavioral components accepted as co-interventions.

DATA COLLECTION AND ANALYSIS

Two reviewers selected relevant trials, assessed methodological quality and extracted data. Where appropriate, data were pooled using meta-analysis with a random-effects model. Positive values favour the intervention group, while negative values favour the control group.

MAIN RESULTS

Three studies included in this systematic review used different kinds of aerobic activity: walking/jogging and rowing training and included participants with a broad age range (17 to 65 years). They were conducted in the USA, Portugal and Israel. In the meta-analyses, only maximal treadmill grade was improved after aerobic exercise training programmes (4.26 grades (%) [95% CI 2.06, 6.45]). Other variables relative to work performance that could not be combined in a meta-analysis were also improved in the intervention group (maximal test time P=0.0003), total turns of fan wheel (P=0.02), resistance of ergometer (p=0.003), power knee extension and flexion (p<0.00001), and timed up and go test (p=0.008). Thirty other outcomes measured in this review including, oxidative stress and body composition variables, could not be combined in the meta-analysis. Apart from work performance, trials reported no statistically significant improvements.

AUTHORS' CONCLUSIONS

There is insufficient evidence to demonstrate that there is improvement in physical or psychosocial outcomes of aerobic exercise in adults with Down syndrome. Although evidence exists to support improvements in physiological and psychological aspects from strategies using mixed physical activity programmes, well-conducted research examining long-term physical outcomes, adverse effects, psychosocial outcomes and costs is required before informed practice decisions can be made.

Comparação do treinamento físico de quatro e oito semanas sobre atividade da cadeia transportadora de elétrons e marcadores de estresse oxidativo em fígado de camundongos

O presente estudo investigou o efeito de quatro e oito semanas de treinamento físico sobre a atividade dos complexos da cadeia transportadora de elétrons (CTE) e os marcadores de estresse oxidativo em fígado de camundongos. Vinte e um camundongos (CF1, 30-35g) foram distribuídos nos seguintes grupos: não treinado (NT); treinado quatro semanas (T4); treinado oito semanas (T8). Quarenta e oito horas após a última sessão de treinamento os animais foram mortos por decapitação e o fígado foi retirado e estocado em -70ºC para posterior análise. Atividade da succinato desidrogenase (SDH), dos complexos I,II,III e IV da CTE, carbonilação de proteína, conteúdo total de tióis e a atividade da superóxido dismutase foram mensurados. Os resultados demonstram que apenas oito semanas de treinamento aumentam a atividade da SDH, dos quatro complexos da CTE, da superóxido dismutase, e o conteúdo total de tióis em relação ao grupo não treinado. Houve ainda diminuição na carbonilação de proteína no respectivo grupo em relação ao NT. Em conclusão, são necessárias oito semanas de treinamento para que ocorram aumento no funcionamento mitocondrial e melhora nos marcadores de estresse oxidativo em fígado de camundongos.

Urinary uric acid and antioxidant capacity in children and adults with Down syndrome

OBJECTIVES

To evaluate the urinary levels of uric acid (UA) and total antioxidant capacity (TAC) with and without UA relative contribution (TAC(-UA)) in children and adults with Down syndrome (DS) and to prove the clinical use of TAC.

DESIGN AND METHODS

Urine samples were obtained from 32 individuals with DS and 29 controls. Two age groups were established (children and adults). Spectrophotometric methods were used for biochemical determinations.

RESULTS

Children with DS had significantly higher UA/Cr and TAC/Cr levels than controls, whereas levels of TAC(-UA)/Cr were lower in adults with DS than in controls (P<0.05 for all). In DS, levels of UA/Cr, TAC/Cr and TAC(-UA)/Cr were higher in children than in adults (P<0.05 for all). Positive correlations between UA/Cr and TAC/Cr were found for all groups studied. Negative correlations with age were found for UA/Cr and TAC/Cr in children of both groups.

CONCLUSIONS

Our results proved that TAC is decreased in adults with DS. Besides, TAC(-UA) seems to provide more reliable information about the antioxidant status, at least in DS.