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Absence of Effects of L-Arginine and L-Citrulline on Inflammatory Biomarkers and Oxidative Stress in Response to Physical Exercise: A Systematic Review with Meta-Analysis.
Porto, AA, Gonzaga, LA, Benjamim, CJR, Valenti, VE
Nutrients. 2023;15(8)
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L-citrulline is a non-essential amino acid that acts as a precursor to L-arginine. L-arginine is a semi-essential amino acid used for nitric oxide production which is crucial for maintaining physiological function and immune regulation. Previous research has shown that L-citrulline and L-arginine supplementation may offer antioxidant and anti-inflammatory benefits in reducing exercise-related oxidative stress and inflammation. This systematic review and meta-analysis included seven randomised controlled trials to investigate the effect of L-citrulline and L-arginine on antioxidants, oxidative stress, and inflammatory and anti-inflammatory markers. This systematic review and meta-analysis showed no significant improvements in oxidative stress and inflammation followed by the supplementation of L-citrulline and L-arginine before exercise. However, further robust studies that include different dosages and exercise intensities are required to assess the beneficial effects of L-citrulline and L-arginine supplements to support physical exercise-induced oxidative stress and inflammation due to the heterogeneity of the included studies. Healthcare professionals can use the results of this study to understand the potential benefits of L-citrulline and L-arginine supplementation in people prone to producing proinflammatory cytokines.
Abstract
The repercussions on oxidative and inflammatory stress markers under the effects of arginine and citrulline in response to exercise are not fully reached. We completed a systematic review to investigate the effects of L-Citrulline or L-Arginine on oxidative stress and inflammatory biomarkers following exercise. EMBASE, MEDLINE (PubMed), Cochrane Library, CINAHL, LILACS, and Web of Science databases were used to record the trials. This study includes randomized controlled trials (RCTs) and non-RCTs with subjects over 18 years old. Those under the intervention protocol consumed L-Citrulline or L-Arginine, and the controls ingested placebo. We recognized 1080 studies, but only 7 were included (7 studies in meta-analysis). We observed no difference between pre- vs. post-exercise for oxidative stress (subtotal = -0.21 [CI: -0.56, 0.14], p = 0.24, and heterogeneity = 0%. In the sub-group "L-Arginine" we found a subtotal = -0.29 [-0.71, 0.12], p = 0.16, and heterogeneity = 0%. For the "L-Citrulline" subgroup we observed a subtotal = 0.00 [-0.67, 0.67], p = 1.00, and heterogeneity was not applicable. No differences were observed between groups (p = 0.47), and I² = 0%) or in antioxidant activity (subtotal = -0.28 [-1.65, 1.08], p = 0.68, and heterogeneity = 0%). In the "L-Arginine" sub-group, we found a subtotal = -3.90 [-14.18, 6.38], p = 0.46, and heterogeneity was not applicable. For the "L-Citrulline" subgroup, we reported a subtotal = -0.22 [-1.60, 1.16], p = 0.75, and heterogeneity was not applicable. No differences were observed between groups (p = 0.49), and I² = 0%), inflammatory markers (subtotal = 8.38 [-0.02, 16.78], p = 0.05, and heterogeneity = 93%. Tests for subgroup differences were not applicable, and anti-inflammatory markers (subtotal = -0.38 [-1.15, 0.39], p = 0.34 and heterogeneity = 15%; testing for subgroup differences was not applicable). In conclusion, our systematic review and meta-analysis found that L-Citrulline and L-Arginine did not influence inflammatory biomarkers and oxidative stress after exercise.
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Polyphenol Intake in Pregnant Women on Gestational Diabetes Risk and Neurodevelopmental Disorders in Offspring: A Systematic Review.
Salinas-Roca, B, Rubió-Piqué, L, Montull-López, A
Nutrients. 2022;14(18)
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In Europe, gestational diabetes affects approximately 10.9% of pregnant women. According to previous research, the cardiometabolic health of the mother and the mother's dietary habits during pregnancy may affect the foetus' neurodevelopment. Taking polyphenol supplements and eating foods rich in polyphenols is beneficial for promoting health across generations. In this systematic review, fourteen studies were included in order to evaluate the effects of polyphenols on gestational diabetes and mental health in the offspring. A higher prevalence of neurodevelopmental diseases in offspring is associated with gestational diabetes. The results of this systematic review revealed that polyphenol intake during pregnancy might have a beneficial effect on improving cardiometabolic health, reducing inflammation, DNA methylation and oxidative stress, thus reducing the risk of developing fetal neurodevelopmental disorders, such as attention deficit hyperactivity disorder, autism spectrum disorder and learning disorders. There is a need for further robust research, as the existing evidence regarding the safety of long-term polyphenol supplementation and its effects on gestational diabetes and fetal neurodevelopment is very limited. In spite of this, healthcare professionals can use the findings of this systematic review to learn more about the positive health benefits of polyphenols in pregnant women.
Abstract
The intake of foods containing polyphenols can have a protective role to avoid comorbidities during pregnancy and, at the same time, promote transgenerational health. This review aims to describe the effect of polyphenol intake through supplements or polyphenol-rich foods during pregnancy on the incidence and evolution of gestational diabetes mellitus (GDM), as well as the link with the neurodevelopment of the fetus. Using PRISMA procedures, a systematic review was conducted by searching in biomedical databases (PubMed, Cinahl and Scopus) from January to June 2022. Full articles were screened (n = 419) and critically appraised. Fourteen studies were selected and were divided into two different thematic blocks considering (i) the effect of polyphenols in GDM and (ii) the effect of GDM to mental disorders in the offspring. A positive relationship was observed between the intake of polyphenols and the prevention and control of cardiometabolic complications during pregnancy, such as GDM, which could be related to thwarted inflammatory and oxidative processes, as well as neuronal factors. GDM is related to a greater risk of suffering from diseases related to neurodevelopment, such as attention deficit hyperactivity disorder, autism spectrum disorder and learning disorder. Further clinical research on the molecule protective mechanism of polyphenols on pregnant women is required to understand the transgenerational impact on fetal neurodevelopment.
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Effectiveness of Exercise Training on Male Factor Infertility: A Systematic Review and Network Meta-analysis.
Hajizadeh Maleki, B, Tartibian, B, Chehrazi, M
Sports health. 2022;14(4):508-517
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Male factor infertility is characterised by the existence of suboptimal sperm parameters in the male partner of childbearing age and is presently defined as the inability to conceive a child with frequent and unprotected sexual intercourse in the fertile phase of the menstrual cycles for a year or longer. The main aim of this study was to evaluate the effectiveness of 1 or more of the selected types of exercise interventions (moderate-intensity continuous training (MICT), resistance training (RT), combined aerobic and resistance training (CET), high-intensity continuous training (HICT), and high-intensity interval training (HIIT)) in the prevention and treatment of male factor infertility. This study is a systematic review and meta-analysis of seven randomised controlled trials representing 18 groups (11 exercise, 7 non-intervention control [NON-EX]) and 2641 participants and/or patients (1429 exercise, 1212 NON-EX). Results show that in the setting of couples with male factor infertility, when compared with the NON-EX group, selected types of exercise interventions improved the relative risk of pregnancy rate in the following order: CET > MICT > RT > HICT > HIIT. The top-ranking interventions for live birth rate were for MICT, RT, HIIT, CET, and HICT. In addition, the interventions with the highest probability of being the best approach out of all available options in improving semen quality parameters were for CET, MICT, HICT, RT, and HIIT. Authors conclude that when clinicians are formulating clinical recommendations for preventing and treating male factor infertility, the findings of this study should be considered.
Expert Review
Conflicts of interest:
None
Take Home Message:
- For couples with male factor infertility, this review recommends moderate intensity-aerobic exercise in combination with strength training to be the intervention with the highest probability of being the best approach for reproductive health benefits.
- A conservative interpretation of the findings is required because they were based on single studies.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
The World Health Organisation estimates that infertility affects 10% to 15% of couples in industrialised countries. Approximately 50% of all infertility cases are attributed to male-related factors, in particular, poor semen quality (called male factor infertility). The aim of this study was to evaluate the effectiveness of exercise training on male factor infertility and seminal markers of inflammation.
Methods
This is the first study to undertake a systematic review with network meta-analysis of 7 RCTs to evaluate the effectiveness of 1 or more types of exercise interventions on male factor infertility and seminal markers of inflammation, as well as to provide clinicians with a ranking of treatments to inform them of the treatment effects of exercise training and physical activity.
The forms of exercise include: moderate-intensity continuous training (MICT), resistance training (RT), combined aerobic and resistance training (CET), high-intensity continuous training (HICT), and high-intensity interval training (HIIT).
7 RCTs representing 18 groups (11 exercise (supervised, not home-based), 7 non-intervention control [NON-EX]) and 2641 participants and/or patients (1429 exercise, 1212 NON-EX). All the RCTs were conducted in Iran involving healthy adult participants and/or infertile patients (with doctor-diagnosed male factor infertility). The intervention period was ≥10 weeks with a follow-up period.
None of the studies reported changes in either patients’ dietary intakes or normal daily physical activities and lifestyles during the intervention period.
Results
Compared with a non-intervention control group, the top ranking interventions:
For pregnancy rate:
Combined aerobic and resistance training (CET) (p= 0.89 relative risk [RR] = 27.81), moderate-intensity continuous training (MICT) (p=0.87, RR = 26.67), resistance training (RT) (p=0.61,RR = 12.54), high intensity continuous training (HICT) (p=0.34, RR = 5.55), and high-intensity interval training (HIIT) (p=0.28, RR = 4.63).
For live birth rate:
MICT (p=0.82, RR = 10.05), RT (p=0.70, RR = 4.92), HIIT (p=0.66, RR = 4.38)), CET (p=0.45, RR = 2.20), and HICT (p=0.30, RR = 1.55)
The following parameters/markers rank the 5 exercise strategies in order of effectiveness:
- Semen quality parameters were significantly improved after the following types of exercise interventions as compared with the non-intervention group [NON-EX]: CET > MICT > HICT > RT > HIIT
- The following training strategies were significantly better at improving seminal markers of oxidative stress: CET > MICT > HIIT > HICT > RT
- The following training strategies were significantly better at improving seminal markers of inflammation: CET > MICT > HIIT > RT > HICT
- The following training strategies were significantly better at improving measures of body composition and VO2 max: CET > HICT > MICT > HIIT > RT
- There was insufficient evidence of a difference for the selected types of exercise interventions versus NON-EX group for pregnancy and live birth rates in healthy participants.
Conclusion
Combined aerobic and resistance training (CET) was found to be the intervention with the highest probability of being the best approach for improving the male factor infertility.
Clinical practice applications:
- In light of these findings, it is reasonable to propose that infertile men and at-risk populations take part in the top-ranking interventions identified in this analysis.
- For substantial reproductive health benefits, one should consider doing all of the selected types of exercise interventions (CET, MICT, RT, HICT, and HIIT); however, moderate intensity-aerobic exercise and strength training in combination would generally be more favourable to lend clinically significant improvements.
- To add to this, exercise can offer a myriad of other health benefits, is a possibly safe activity and a cost-effective treatment strategy for male factor infertility.
Considerations for future research:
- There was only a small number of relevant trials available for comparison suggesting the need for additional study in this field.
- Further trials are needed to analyse the dose-response impacts of exercise modalities on male reproductive function.
- The results propose several domains for development in the reporting of RCTs addressing the impacts of interventional exercise studies on male reproductive function.
- Heterogeneity of some findings and discrepancy across the included studies was significant. For example, variations in the characteristics of training programs. Future analyses should aim to continue to address this.
- There is a concern that this study may not relate to already active patients with male factor infertility which future studies should address.
Abstract
CONTEXT Mounting evidence from the literature suggests that different types of training interventions can be successful at improving several aspects of male reproductive function in both fertile and infertile populations. OBJECTIVE The aim of this study was to evaluate the effectiveness of exercise training on male factor infertility and seminal markers of inflammation. DATA SOURCES We searched PubMed, CISCOM, Springer, Elsevier Science, Cochrane Central Register of Controlled Trials, Scopus, PEDro, Ovid (Medline, EMBASE, PsycINFO), Sport Discus, Orbis, CINAHL, Web of Science, ProQuest, and the ClinicalTrials.gov registry for randomized controlled trials (RCTs) that analyzed the impacts of selected types of exercise interventions on markers of male reproductive function and reproductive performance. STUDY SELECTION A total of 336 records were identified, of which we included 7 trials reporting on 2641 fertile and infertile men in the systematic review and network meta-analysis. LEVEL OF EVIDENCE Level 1 (because this is a systematic review of RCTs). DATA EXTRACTION The data included the study design, participant characteristics, inclusion and exclusion, intervention characteristics, outcome measures, and the main results of the study. RESULTS The results of network meta-analysis showed that, compared with a nonintervention control group, the top-ranking interventions for pregnancy rate were for combined aerobic and resistance training (CET) (relative risk [RR] = 27.81), moderate-intensity continuous training (MICT) (RR = 26.67), resistance training (RT) (RR = 12.54), high-intensity continuous training (HICT) (RR = 5.55), and high-intensity interval training (HIIT) (RR = 4.63). While the top-ranking interventions for live birth rate were for MICT (RR = 10.05), RT (RR = 4.92), HIIT (RR = 4.38), CET (RR = 2.20), and HICT (RR = 1.55). Also, with the following order of effectiveness, 5 training strategies were significantly better at improving semen quality parameters (CET > MICT > HICT > RT > HIIT), seminal markers of oxidative stress (CET > MICT > HIIT > HICT > RT), seminal markers of inflammation (CET > MICT > HIIT > RT > HICT), as well as measures of body composition and VO2max (CET > HICT > MICT > HIIT > RT). CONCLUSION The review recommends that the intervention with the highest probability of being the best approach out of all available options for improving the male factor infertility was for CET.
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A double-blinded, randomized, parallel intervention to evaluate biomarker-based nutrition plans for weight loss: The PREVENTOMICS study.
Aldubayan, MA, Pigsborg, K, Gormsen, SMO, Serra, F, Palou, M, Galmés, S, Palou-March, A, Favari, C, Wetzels, M, Calleja, A, et al
Clinical nutrition (Edinburgh, Scotland). 2022;41(8):1834-1844
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Obesity, and particularly abdominal adiposity, is associated with various metabolic abnormalities. Diet has a vital role in preventing and managing obesity, but evidence from clinical studies demonstrates there is a great interindividual variability in response to the same dietary intervention, which likely indicates that no one diet is superior to another. The aim of this study was to examine the efficacy of the PREVENTOMICS (empowering consumers to PREVENT diet-related diseases through OMICS sciences) platform, incorporated in an e-commerce digital tool, for producing more favourable health outcomes over dietary plans based on general diet recommendations, in subjects with overweight or obesity and elevated waist circumference. This study is a 10-week randomised single-centre, parallel-group, double-blinded intervention study. Participants were allocated in a 1:1 ratio, stratified by cluster to either the intervention group (personalised plan) or the control group (generic recommendations). Results show that there isn’t any additional benefit of personalising dietary plans, over a generic approach, on the change in fat mass and body weight in individuals with overweight or obesity and elevated waist circumference. Accordingly, personalisation of the diet did not significantly improve health parameters beyond the changes induced by the control diet. Participants in both groups lost approximately 3 kg of body weight. Authors conclude that based on their findings evidence to translate personalised nutrition approaches into clinical practice is insufficient.
Abstract
BACKGROUND & AIMS Growing evidence suggests that biomarker-guided dietary interventions can optimize response to treatment. In this study, we evaluated the efficacy of the PREVENTOMCIS platform-which uses metabolomic and genetic information to classify individuals into different 'metabolic clusters' and create personalized dietary plans-for improving health outcomes in subjects with overweight or obesity. METHODS A 10-week parallel, double-blinded, randomized intervention was conducted in 100 adults (82 completers) aged 18-65 years, with body mass index ≥27 but <40 kg/m2, who were allocated into either a personalized diet group (n = 49) or a control diet group (n = 51). About 60% of all food was provided free-of-charge. No specific instruction to restrict energy intake was given. The primary outcome was change in fat mass from baseline, evaluated by dual energy X-ray absorptiometry. Other endpoints included body weight, waist circumference, lipid profile, glucose homeostasis markers, inflammatory markers, blood pressure, physical activity, stress and eating behavior. RESULTS There were significant main effects of time (P < 0.01), but no group main effects, or time-by-group interactions, for the change in fat mass (personalized: -2.1 [95% CI -2.9, -1.4] kg; control: -2.0 [95% CI -2.7, -1.3] kg) and body weight (personalized: -3.1 [95% CI -4.1, -2.1] kg; control: -3.3 [95% CI -4.2, -2.4] kg). The difference between groups in fat mass change was -0.1 kg (95% CI -1.2, 0.9 kg, P = 0.77). Both diets resulted in significant improvements in insulin resistance and lipid profile, but there were no significant differences between groups. CONCLUSION Personalized dietary plans did not result in greater benefits over a generic, but generally healthy diet, in this 10-week clinical trial. Further studies are required to establish the soundness of different precision nutrition approaches, and translate this science into clinically relevant dietary advice to reduce the burden of obesity and its comorbidities. CLINICAL TRIAL REGISTRY ClinicalTrials.gov registry (NCT04590989).
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MitoQ supplementation augments acute exercise-induced increases in muscle PGC1α mRNA and improves training-induced increases in peak power independent of mitochondrial content and function in untrained middle-aged men.
Broome, SC, Pham, T, Braakhuis, AJ, Narang, R, Wang, HW, Hickey, AJR, Mitchell, CJ, Merry, TL
Redox biology. 2022;53:102341
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Exercise-induced stressors trigger an acute and transient upregulation of gene expression in skeletal muscle that, if reinforced by repeated exercise bouts as part of an exercise training program, results in phenotypic adaptations that improve skeletal muscle function. The aim of this study was to investigate the effect of mitochondria-targeted coenzyme Q10 (mitoquidone; MitoQ) supplementation on a) skeletal muscle mitochondrial and antioxidant gene transcriptional response to acute high-intensity exercise and b) skeletal muscle mitochondrial content and function following exercise training. This study is a double-blind, placebo-controlled parallel design study. Participants were randomised to receive MitoQ or an identical placebo. Participants were instructed to consume one tablet per day 30 min before breakfast for 10 days before the acute exercise trial until completion of the final study visit. Results show that the acute exercise-induced transcriptional response and training-induced mitochondrial adaptations in skeletal muscle are not attenuated by MitoQ supplementation. Furthermore, MitoQ enhances the effect of exercise training on peak power achieved during a ramp-incremental exercise test. Authors conclude that training-induced increases in peak power are enhanced following MitoQ supplementation. However, these effects do not appear to be related to an effect of MitoQ supplementation on exercise-induced oxidative stress or training-induced mitochondrial biogenesis in skeletal muscle.
Abstract
The role of mitochondrial ROS in signalling muscle adaptations to exercise training has not been explored in detail. We investigated the effect of supplementation with the mitochondria-targeted antioxidant MitoQ on a) the skeletal muscle mitochondrial and antioxidant gene transcriptional response to acute high-intensity exercise and b) skeletal muscle mitochondrial content and function following exercise training. In a randomised, double-blind, placebo-controlled, parallel design study, 23 untrained men (age: 44 ± 7 years, VO2peak: 39.6 ± 7.9 ml/kg/min) were randomised to receive either MitoQ (20 mg/d) or a placebo for 10 days before completing a bout of high-intensity interval exercise (cycle ergometer, 10 × 60 s at VO2peak workload with 75 s rest). Blood samples and vastus lateralis muscle biopsies were collected before exercise and immediately and 3 h after exercise. Participants then completed high-intensity interval training (HIIT; 3 sessions per week for 3 weeks) and another blood sample and muscle biopsy were collected. There was no effect of acute exercise or MitoQ on systemic (plasma protein carbonyls and reduced glutathione) or skeletal muscle (mtDNA damage and 4-HNE) oxidative stress biomarkers. Acute exercise-induced increases in skeletal muscle peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1-α) mRNA expression were augmented in the MitoQ group. Despite this, training-induced increases in skeletal muscle mitochondrial content were similar between groups. HIIT-induced increases in VO2peak and 20 km time trial performance were also similar between groups while training-induced increases in peak power achieved during the VO2peak test were augmented in the MitoQ group. These data suggest that training-induced increases in peak power are enhanced following MitoQ supplementation, which may be related to the augmentation of skeletal muscle PGC1α expression following acute exercise. However, these effects do not appear to be related to an effect of MitoQ supplementation on exercise-induced oxidative stress or training-induced mitochondrial biogenesis in skeletal muscle.
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Nutritional intervention for diabetes mellitus with Alzheimer's disease.
Li, Z, Li, S, Xiao, Y, Zhong, T, Yu, X, Wang, L
Frontiers in nutrition. 2022;9:1046726
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Diabetes Mellitus (DM) affects more than 463 million people worldwide. Similarly, the number of deaths related to Alzheimer’s disease (AD) has increased by 145%. There are several common risk factors for Type 2 Diabetes and AD, including obesity, insulin resistance, and ageing, as well as common pathological mechanisms, including altered insulin signalling, oxidative stress, neuroinflammation, mitochondrial dysfunction, formation of glycated proteins and metabolic syndrome. This review aims to summarize the therapeutic effects of different nutritional therapy strategies on the reduction of DM and AD risk. Controlling blood sugar levels and reducing calorie intake is crucial to preventing diabetes and Alzheimer's disease. The low-carbohydrate, ketogenic, and Mediterranean diets have been found to improve glucose control in people with Type 2 diabetes (T2D). In addition, MIND (Mediterranean-DASH Diet Intervention for Neurodegenerative Delay) and a ketogenic diet may improve cognition in AD patients. Lactobacillus, Bifidobacterium probiotics, and prebiotics, such as inulin, may inhibit the progression of T2D and AD diseases by suppressing inflammation and modulating gut microbes. In addition, vitamins A, C, D, E, B6, B12, folate, long-chain polyunsaturated fatty acids, zinc, magnesium, and polyphenols may improve cognitive decline, homocysteine levels, and insulin resistance in AD and T2D patients. Healthcare professionals can use the results of this review to understand the beneficial effects of dietary strategies and multi-nutrient supplementation on DM and AD. However, further robust studies are required to investigate the risk factors and underlying mechanisms behind DM-combined AD progression.
Abstract
The combined disease burden of diabetes mellitus (DM) and Alzheimer's disease (AD) is increasing, and the two diseases share some common pathological changes. However, the pharmacotherapeutic approach to this clinical complexity is limited to symptomatic rather than disease-arresting, with the possible exception of metformin. Whether nutritional intervention might extend or synergize with these effects of metformin is of interest. In particular, dietary patterns with an emphasis on dietary diversity shown to affect cognitive function are of growing interest in a range of food cultural settings. This paper presents the association between diabetes and AD. In addition, the cross-cultural nutritional intervention programs with the potential to mitigate both insulin resistance (IR) and hyperglycemia, together with cognitive impairment are also reviewed. Both dietary patterns and nutritional supplementation showed the effects of improving glycemic control and reducing cognitive decline in diabetes associated with AD, but the intervention specificity remained controversial. Multi-nutrient supplements combined with diverse diets may have preventive and therapeutic potential for DM combined with AD, at least as related to the B vitamin group and folate-dependent homocysteine (Hcy). The nutritional intervention has promise in the prevention and management of DM and AD comorbidities, and more clinical studies would be of nutritional scientific merit.
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Mitochondria-targeted antioxidant supplementation improves 8 km time trial performance in middle-aged trained male cyclists.
Broome, SC, Braakhuis, AJ, Mitchell, CJ, Merry, TL
Journal of the International Society of Sports Nutrition. 2021;18(1):58
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Oxygen-derived radical and non-radical species, collectively referred to as reactive oxygen species (ROS), are continuously produced by skeletal muscle. High levels of ROS production in cells may overwhelm the endogenous antioxidant defence network resulting in damage to cellular proteins, lipids and DNA and impaired cellular function. The aim of this study was to investigate whether Mitochondria-targeted coenzyme Q10 (MitoQ), supplementation could improve the time taken to complete an 8 km cycling time trial. This study is a double-blind, placebo-controlled crossover design trial. Twenty-two healthy middle-aged, recreationally trained male cyclists were recruited via advertisements. They were randomised by an independent researcher to two groups, which would determine the order in which they received MitoQ and an identical placebo. Results show that oral supplementation of the mitochondria-targeted antioxidant MitoQ can improve cycling time trial performance in middle-aged, recreationally trained male cyclists. In fact, MitoQ may improve performance above the aerobic threshold by allowing for increased use of anaerobic metabolism, or by improving tolerance to lower pH in muscle. Authors conclude that further research is required to determine the mechanisms responsible for the ergogenic effect of MitoQ, understand the important factors that determine an individual’s response to MitoQ supplementation, and identify optimal dosing strategies.
Abstract
BACKGROUND Exercise increases skeletal muscle reactive oxygen species (ROS) production, which may contribute to the onset of muscular fatigue and impair athletic performance. Mitochondria-targeted antioxidants such as MitoQ, which contains a ubiquinone moiety and is targeted to mitochondria through the addition of a lipophilic triphenylphosphonium cation, are becoming popular amongst active individuals as they are designed to accumulate within mitochondria and may provide targeted protection against exercise-induced oxidative stress. However, the effect of MitoQ supplementation on cycling performance is currently unknown. Here, we investigate whether MitoQ supplementation can improve cycling performance measured as time to complete an 8 km time trial. METHOD In a randomized, double-blind, placebo-controlled crossover study, 19 middle-aged (age: 44 ± 4 years) recreationally trained (VO2peak: 58.5 ± 6.2 ml·kg- 1·min- 1, distance cycled per week during 6 months prior to study enrollment: 158.3 ± 58.4 km) male cyclists completed 45 min cycling at 70% VO2peak followed by an 8 km time trial after 28 days of supplementation with MitoQ (20 mg·day- 1) and a placebo. Free F2-isoprostanes were measured in plasma samples collected at rest, after 45 min cycling at 70% VO2peak and after completion of the time trial. Respiratory gases and measures of rating of perceived exertion (RPE) were also collected. RESULTS Mean completion time for the time trial was 1.3% faster with MitoQ (12.91 ± 0.94 min) compared to placebo (13.09 ± 0.95 min, p = 0.04, 95% CI [0.05, 2.64], d = 0.2). There was no difference in RPE during the time trial between conditions (p = 0.82) despite there being a 4.4% increase in average power output during the time trial following MitoQ supplementation compared to placebo (placebo; 270 ± 51 W, MitoQ; 280 ± 53 W, p = 0.04, 95% CI [0.49, 8.22], d = 0.2). Plasma F2-isoprostanes were lower on completion of the time trial following MitoQ supplementation (35.89 ± 13.6 pg·ml- 1) compared to placebo (44.7 ± 16.9 pg·ml- 1 p = 0.03). CONCLUSION These data suggest that MitoQ supplementation may be an effective nutritional strategy to attenuate exercise-induced increases in oxidative damage to lipids and improve cycling performance.
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The effects of phosphocreatine disodium salts plus blueberry extract supplementation on muscular strength, power, and endurance.
Anders, JPV, Neltner, TJ, Smith, RW, Keller, JL, Housh, TJ, Daugherty, FJ, Tempesta, MS, Dash, AK, Munt, DJ, Schmidt, RJ, et al
Journal of the International Society of Sports Nutrition. 2021;18(1):60
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The effects of polyphenols and phosphocreatine supplementation on exercise performance, muscular strength, power, and endurance are largely unknown. This randomised, double-blinded, placebo-controlled, parallel-design trial aimed to differentiate the effects of a blend of 5 grams of phosphocreatine disodium salts plus 200 mg blueberry extract (PCDSB), 3 grams of Creatinine monohydrate (CM), and placebo on measures of muscular strength, power, and endurance. PCDSB contained 60 grams of phenols and 2.5 grams of pure creatine, and CM contained 2.4 grams of pure creatin. During this trial, thirty-three men took random supplements for 28 days and kept up their regular exercise regimen. In both PCDSB and CM, Peak torque (PT) and Average power (AP) increased after 28 days of supplementation with no effect on fatigue-induced PT% and AP% or body mass. Additionally, a greater proportion of participants showed a meaningful increase in muscular strength to PCDSB than to CM. To evaluate the additive effects of ingredients in the PCDSB supplement, longer-term studies are needed with larger supplementation doses. The study provides insight into the ergogenic effects of PCDSB and CM for healthcare practitioners.
Abstract
BACKGROUND Numerous studies have demonstrated the efficacy of creatine supplementation for improvements in exercise performance. Few studies, however, have examined the effects of phosphocreatine supplementation on exercise performance. Furthermore, while polyphenols have antioxidant and anti-inflammatory properties, little is known regarding the influence of polyphenol supplementation on muscular strength, power, and endurance. Thus, the purpose of the present study was to compare the effects of 28 days of supplementation with phosphocreatine disodium salts plus blueberry extract (PCDSB), creatine monohydrate (CM), and placebo on measures of muscular strength, power, and endurance. METHODS Thirty-three men were randomly assigned to consume either PCDSB, CM, or placebo for 28 days. Peak torque (PT), average power (AP), and percent decline for peak torque (PT%) and average power (AP%) were assessed from a fatigue test consisting of 50 maximal, unilateral, isokinetic leg extensions at 180°·s- 1 before and after the 28 days of supplementation. Individual responses were assessed to examine the proportion of subjects that exceeded a minimal important difference (MID). RESULTS The results demonstrated significant (p < 0.05) improvements in PT for the PCDSB and CM groups from pre- (99.90 ± 22.47 N·m and 99.95 ± 22.50 N·m, respectively) to post-supplementation (119.22 ± 29.87 N·m and 111.97 ± 24.50 N·m, respectively), but no significant (p = 0.112) change for the placebo group. The PCDSB and CM groups also exhibited significant improvements in AP from pre- (140.18 ± 32.08 W and 143.42 ± 33.84 W, respectively) to post-supplementation (170.12 ± 42.68 W and 159.78 ± 31.20 W, respectively), but no significant (p = 0.279) change for the placebo group. A significantly (p < 0.05) greater proportion of subjects in the PCDSB group exceeded the MID for PT compared to the placebo group, but there were no significant (p > 0.05) differences in the proportion of subjects exceeding the MID between the CM and placebo groups or between the CM and PCDSB groups. CONCLUSIONS These findings indicated that for the group mean responses, 28 days of supplementation with both PCDSB and CM resulted in increases in PT and AP. The PCDSB, however, may have an advantage over CM when compared to the placebo group for the proportion of individuals that respond favorably to supplementation with meaningful increases in muscular strength.
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Diet to Reduce the Metabolic Syndrome Associated with Menopause. The Logic for Olive Oil.
Hidalgo-Mora, JJ, Cortés-Sierra, L, García-Pérez, MÁ, Tarín, JJ, Cano, A
Nutrients. 2020;12(10)
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Metabolic syndrome (MetS) is a group of risk factors that increase the risk of type 2 diabetes and cardiovascular disease. The rates of MetS are increasing worldwide. Obesity, particularly central obesity is a major determinant of insulin resistance. It is believed that insulin resistance is the driver for MetS. This is a particular concern for women as central obesity is more likely to occur during the menopause, due in part to the hormonal changes. Physical activity and nutrition have been recommended as the first line of defence against MetS with the Mediterranean diet (MD) being one of the healthiest options. Olive oil (OO) is a main component of the MD and contains certain fats and polyphenols which impact inflammation, oxidative stress and support the gut microbiome. This review provides an overview of these benefits most relevant to menopause-associated MetS. A healthy lifestyle, with nutrition as a vital component, needs to be implemented as a primary measure. The healthy diet needs to be easy to follow and effective, two conditions successfully met by the MD. OO may prove especially helpful for women, particularly during this life stage. The clinical evidence, however, is limited by the observational nature of most studies.
Abstract
The rates of metabolic syndrome are increasing in parallel with the increasing prevalence of obesity, primarily due to its concomitant insulin resistance. This is particularly concerning for women, as the years around menopause are accompanied by an increase in visceral obesity, a strong determinant of insulin resistance. A fall in estrogens and increase in the androgen/estrogen ratio is attributed a determining role in this process, which has been confirmed in other physiological models, such as polycystic ovary syndrome. A healthy lifestyle, with special emphasis on nutrition, has been recommended as a first-line strategy in consensuses and guidelines. A consistent body of evidence has accumulated suggesting that the Mediterranean diet, with olive oil as a vital component, has both health benefits and acceptable adherence. Herein, we provide an updated overview of current knowledge on the benefits of olive oil most relevant to menopause-associated metabolic syndrome, including an analysis of the components with the greatest health impact, their effect on basic mechanisms of disease, and the state of the art regarding their action on the main features of metabolic syndrome.
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Rhodiola/Cordyceps-Based Herbal Supplement Promotes Endurance Training-Improved Body Composition But Not Oxidative Stress and Metabolic Biomarkers: A Preliminary Randomized Controlled Study.
Liao, YH, Chao, YC, Sim, BY, Lin, HM, Chen, MT, Chen, CY
Nutrients. 2019;11(10)
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Physical inactivity has negative health consequences. Such consequences include muscle loss, weight gain, low-grade inflammation, oxidative stress and increased disease risk for metabolic disorders such as type 2 diabetes and cardiovascular diseases. The development of such chronic metabolic disorders often starts at a much younger age, long before it manifests as clinical disease decades later. Endurance exercise is one way to reduce the development and progression of metabolic disease. In addition, the herb Rhodiola crenulata (RC) and fungus Cordyceps sinensis (CS) have shown to bear benefits on metabolic disease parameters. Both have long been used in Chinese medicine for their health-promoting, antioxidant and anti-inflammatory effects. This study sought to assess whether the benefits of regular endurance training can be futher enhanced with the supplementation of RC and CS. This randomized, double-blind, placebo-controlled trial enrolled 14 young sedentary adults who received an 8-week endurance training program. They also received either supplements or a placebo. Measurements and markers of body composition, oxidative stress and metabolic function were obtained before and after the intervention. The results found no difference in blood fats and oxidative stress markers between groups. In fact endurance training alone improved endurance capacity and glycemic control, but again with no particular difference between control and intervention. However, the supplementation group showed improvement in body composition with reduced body fat and increased muscle mass compared to the control group. Larger studies are needed to strengthen the results.
Abstract
Rhodiola crenulata (R) and Cordyceps sinensis (C) are commonly used herbs that promote health in traditional Chinese medicine. These two herbs have also been shown to exhibit anti-inflammation and antioxidant functions. Regular endurance training reveals potent endurance capacity, body composition improvement, and metabolic-related biomarker benefits. However, it is not known whether the combination of Rhodiola crenulata and Cordyceps sinensis (RC) supplementation during endurance training provides additive health benefits. The purpose of this study was to investigate the effects of 8-week endurance training plus RC supplementation on body composition, oxidative stress, and metabolic biomarkers in young sedentary adults. METHODS Fourteen young sedentary adults (8M/6F) participated in this double-blind randomized controlled study. Participants were assigned to exercise training with placebo groups (PLA, n = 7, 4M/3F; age: 21.4 ± 0.4 years) and exercise training with the RC group (RC, 20 mg/kg/day; n = 7, 4M/3F; age: 21.7 ± 0.4 years). Both groups received identical exercise training for eight weeks. The body composition, circulating oxidative stress, and blood metabolic biomarkers were measured before and after the 8-week intervention. RESULTS Improvement in body composition profiles were significantly greater in the RC group (body weight: p = 0.044, BMI: p = 0.003, upper extremity fat mass: p = 0.032, lower extremity muscle mass: p = 0.029, trunk fat mass: p = 0.011) compared to the PLA group after training. The blood lipid profile and systemic oxidative stress makers (thiobarbituric reactive substanceand total antioxidant capacity) did not differ between groups. Although endurance training markedly improved endurance capacity and glycemic control ability (i.e., fast blood glucose, insulin, and HOMA index), there were no differences in these variables between treatments. CONCLUSIONS In this preliminary investigation, we demonstrated that an 8-week RC supplementation (20 mg/kg/day) faintly enhanced endurance training-induced positive adaptations in body composition in young sedentary individuals, whereas the blood lipid profile and systemic oxidative stress states were not altered after such intervention.