-
Clinical Nutrition ESPEN Jun 2020Clinical evidence which investigated the effects of l-carnitine, a vitamin-like substance, on weight loss had led to inconsistent results. This study therefore aimed to... (Meta-Analysis)
Meta-Analysis Review
Effects of l-carnitine supplementation on weight loss and body composition: A systematic review and meta-analysis of 37 randomized controlled clinical trials with dose-response analysis.
BACKGROUND AND AIM
Clinical evidence which investigated the effects of l-carnitine, a vitamin-like substance, on weight loss had led to inconsistent results. This study therefore aimed to examine the effect of l-carnitine supplementation on body weight and composition by including the maximum number of randomized controlled trials (RCTs) and to conduct a dose-response analysis, for the first time.
METHODS AND RESULTS
Online databases were searched up to January 2019. In total, 37 RCTs (with 2292 participants) were eligible. Meta-analysis showed that l-carnitine supplementation significantly decreased body weight [Weighted mean difference (WMD) = -1.21 kg, 95% confidence interval (CI): -1.73, -0.68; P < 0.001], body mass index (BMI) (WMD = -0.24 kg/m, 95% CI: -0.37, -0.10; P = 0.001), and fat mass (WMD = -2.08 kg, 95% CI: -3.44, -0.72; P = 0.003). No significant effect was seen for waist circumference (WC) and body fat percent. The meta-analysis of high-quality RCTs only confirmed the effect on body weight. A non-linear dose-response association was seen between l-carnitine supplementation and body weight reduction (P < 0.001) suggesting that ingestion of 2000 mg l-carnitine per day provides the maximum effect in adults. This association was not seen for BMI, WC and body fat percent.
CONCLUSIONS
l-carnitine supplementation provides a modest reducing effect on body weight, BMI and fat mass, especially among adults with overweight/obesity.
Topics: Adult; Body Composition; Body Weight; Carnitine; Dietary Supplements; Humans; Randomized Controlled Trials as Topic; Weight Loss
PubMed: 32359762
DOI: 10.1016/j.clnesp.2020.03.008 -
Theranostics 2023Metabolic reprogramming is one of the most important hallmarks of malignant tumors. Specifically, lipid metabolic reprogramming has marked impacts on cancer progression... (Review)
Review
Metabolic reprogramming is one of the most important hallmarks of malignant tumors. Specifically, lipid metabolic reprogramming has marked impacts on cancer progression and therapeutic response by remodeling the tumor microenvironment (TME). In the past few decades, immunotherapy has revolutionized the treatment landscape for advanced cancers. Lipid metabolic reprogramming plays pivotal role in regulating the immune microenvironment and response to cancer immunotherapy. Here, we systematically reviewed the characteristics, mechanism, and role of lipid metabolic reprogramming in tumor and immune cells in the TME, appraised the effects of various cell death modes (specifically ferroptosis) on lipid metabolism, and summarized the antitumor therapies targeting lipid metabolism. Overall, lipid metabolic reprogramming has profound effects on cancer immunotherapy by regulating the immune microenvironment; therefore, targeting lipid metabolic reprogramming may lead to the development of innovative clinical applications including sensitizing immunotherapy.
Topics: Humans; Tumor Microenvironment; Lipid Metabolism; Immunotherapy; Cell Death; Lipids; Neoplasms
PubMed: 37064872
DOI: 10.7150/thno.82920 -
Nutrients Jan 2021Although creatine has been mostly studied as an ergogenic aid for exercise, training, and sport, several health and potential therapeutic benefits have been reported....
Although creatine has been mostly studied as an ergogenic aid for exercise, training, and sport, several health and potential therapeutic benefits have been reported. This is because creatine plays a critical role in cellular metabolism, particularly during metabolically stressed states, and limitations in the ability to transport and/or store creatine can impair metabolism. Moreover, increasing availability of creatine in tissue may enhance cellular metabolism and thereby lessen the severity of injury and/or disease conditions, particularly when oxygen availability is compromised. This systematic review assesses the peer-reviewed scientific and medical evidence related to creatine's role in promoting general health as we age and how creatine supplementation has been used as a nutritional strategy to help individuals recover from injury and/or manage chronic disease. Additionally, it provides reasonable conclusions about the role of creatine on health and disease based on current scientific evidence. Based on this analysis, it can be concluded that creatine supplementation has several health and therapeutic benefits throughout the lifespan.
Topics: Aging; Biological Availability; Chronic Disease; Creatine; Dietary Supplements; Humans; Wounds and Injuries
PubMed: 33572884
DOI: 10.3390/nu13020447 -
Nutrients Aug 2021A low-carbohydrate, high-fat (LCHF) diet has been proposed to enhance the fat utilization of muscle and the aerobic capacity of endurance athletes, thereby improving... (Meta-Analysis)
Meta-Analysis
A low-carbohydrate, high-fat (LCHF) diet has been proposed to enhance the fat utilization of muscle and the aerobic capacity of endurance athletes, thereby improving their exercise performance. However, it remains uncertain how the macronutrient intake shift from carbohydrate to fat affects endurance exercise training and performance. This study performed a systematic review and meta-analysis to explore the effects of a ketogenic low-carbohydrate, high-fat (K-LCHF) diet on aerobic capacity and exercise performance among endurance athletes. Searches were carried out in five electronic databases, and we followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. The search included studies using an LCHF diet as an intervention protocol and compared data on factors such as maximum oxygen uptake (VOmax) and rating of perceived exertion (RPE) from the graded exercise test. In this case, 10 studies met the criteria and were included in the meta-analysis. We did not find a significant effect of K-LCHF diet interventions on VOmax, time to exhaustion, HRmax or RPE. However, a significant overall effect in the substrate oxidation response to respiratory exchange rate was observed. The meta-analysis showed that K-LCHF diets did not affect aerobic capacity and exercise performance. Therefore, high-quality interventions of a K-LCHF diet are needed to illustrate its effect on various endurance training programs.
Topics: Adult; Athletes; Diet, Ketogenic; Exercise Tolerance; Female; Hemodynamics; Humans; Male; Middle Aged; Nutritive Value; Oxygen Consumption; Physical Conditioning, Human; Physical Endurance; Respiratory Mechanics; Young Adult
PubMed: 34445057
DOI: 10.3390/nu13082896 -
Nutrients Feb 2023There has been an emerging concern that non-nutritive sweeteners (NNS) can increase the risk of cardiometabolic disease. Much of the attention has focused on acute... (Meta-Analysis)
Meta-Analysis
There has been an emerging concern that non-nutritive sweeteners (NNS) can increase the risk of cardiometabolic disease. Much of the attention has focused on acute metabolic and endocrine responses to NNS. To examine whether these mechanisms are operational under real-world scenarios, we conducted a systematic review and network meta-analysis of acute trials comparing the effects of non-nutritive sweetened beverages (NNS beverages) with water and sugar-sweetened beverages (SSBs) in humans. MEDLINE, EMBASE, and The Cochrane Library were searched through to January 15, 2022. We included acute, single-exposure, randomized, and non-randomized, clinical trials in humans, regardless of health status. Three patterns of intake were examined: (1) uncoupling interventions, where NNS beverages were consumed alone without added energy or nutrients; (2) coupling interventions, where NNS beverages were consumed together with added energy and nutrients as carbohydrates; and (3) delayed coupling interventions, where NNS beverages were consumed as a preload prior to added energy and nutrients as carbohydrates. The primary outcome was a 2 h incremental area under the curve (iAUC) for blood glucose concentration. Secondary outcomes included 2 h iAUC for insulin, glucagon-like peptide 1 (GLP-1), gastric inhibitory polypeptide (GIP), peptide YY (PYY), ghrelin, leptin, and glucagon concentrations. Network meta-analysis and confidence in the network meta-analysis (CINeMA) were conducted in R-studio and CINeMA, respectively. Thirty-six trials involving 472 predominantly healthy participants were included. Trials examined a variety of single NNS (acesulfame potassium, aspartame, cyclamate, saccharin, stevia, and sucralose) and NNS blends (acesulfame potassium + aspartame, acesulfame potassium + sucralose, acesulfame potassium + aspartame + cyclamate, and acesulfame potassium + aspartame + sucralose), along with matched water/unsweetened controls and SSBs sweetened with various caloric sugars (glucose, sucrose, and fructose). In uncoupling interventions, NNS beverages (single or blends) had no effect on postprandial glucose, insulin, GLP-1, GIP, PYY, ghrelin, and glucagon responses similar to water controls (generally, low to moderate confidence), whereas SSBs sweetened with caloric sugars (glucose and sucrose) increased postprandial glucose, insulin, GLP-1, and GIP responses with no differences in postprandial ghrelin and glucagon responses (generally, low to moderate confidence). In coupling and delayed coupling interventions, NNS beverages had no postprandial glucose and endocrine effects similar to controls (generally, low to moderate confidence). The available evidence suggests that NNS beverages sweetened with single or blends of NNS have no acute metabolic and endocrine effects, similar to water. These findings provide support for NNS beverages as an alternative replacement strategy for SSBs in the acute postprandial setting.
Topics: Humans; Sugar-Sweetened Beverages; Aspartame; Ghrelin; Glucagon; Cyclamates; Network Meta-Analysis; Blood Glucose; Glucose; Non-Nutritive Sweeteners; Beverages; Sucrose; Insulin; Sugars; Glucagon-Like Peptide 1; Water
PubMed: 36839408
DOI: 10.3390/nu15041050 -
International Journal of Molecular... Aug 2022Background: Glioblastoma (GBM) is a highly aggressive cancer with poor prognosis that needs better treatment modalities. Moreover, there is a lack of reliable biomarkers... (Meta-Analysis)
Meta-Analysis Review
Background: Glioblastoma (GBM) is a highly aggressive cancer with poor prognosis that needs better treatment modalities. Moreover, there is a lack of reliable biomarkers to predict the response and outcome of current or newly designed therapies. While several molecular markers have been proposed as potential biomarkers for GBM, their uptake into clinical settings is slow and impeded by marker heterogeneity. Detailed assessment of prognostic and predictive value for biomarkers in well-defined clinical trial settings, if available, is scattered throughout the literature. Here we conducted a systematic review and meta-analysis to evaluate the prognostic and predictive significance of clinically relevant molecular biomarkers in GBM patients. Material and methods: A comprehensive literature search was conducted to retrieve publications from 3 databases (Pubmed, Cochrane and Embase) from January 2010 to December 2021, using specific terms. The combined hazard ratios (HR) and confidence intervals (95% CI) were used to evaluate the association of biomarkers with overall survival (OS) in GBM patients. Results: Twenty-six out of 1831 screened articles were included in this review. Nineteen articles were included in the meta-analyses, and 7 articles were quantitatively summarised. Fourteen studies with 1231 GBM patients showed a significant association of MGMT methylation with better OS with the pooled HR of 1.66 (95% CI 1.32−2.09, p < 0.0001, random effect). Five studies including 541 GBM patients analysed for the prognostic significance of IDH1 mutation showed significantly better OS in patients with IDH1 mutation with a pooled HR of 2.37 (95% CI 1.81−3.12; p < 0.00001]. Meta-analysis performed on 5 studies including 575 GBM patients presenting with either amplification or high expression of EGFR gene did not reveal any prognostic significance with a pooled HR of 1.31 (95% CI 0.96−1.79; p = 0.08). Conclusions: MGMT promoter methylation and IDH1 mutation are significantly associated with better OS in GBM patients. No significant associations were found between EGFR amplification or overexpression with OS.
Topics: Biomarkers; Biomarkers, Tumor; Brain Neoplasms; DNA Methylation; DNA Modification Methylases; DNA Repair Enzymes; Glioblastoma; Humans; Tumor Suppressor Proteins
PubMed: 36012105
DOI: 10.3390/ijms23168835 -
Sports Medicine (Auckland, N.Z.) Feb 2022Body-fluid loss during prolonged continuous exercise can impair cardiovascular function, harming performance. Delta percent plasma volume (dPV) represents the change in... (Meta-Analysis)
Meta-Analysis
The Hydrating Effects of Hypertonic, Isotonic and Hypotonic Sports Drinks and Waters on Central Hydration During Continuous Exercise: A Systematic Meta-Analysis and Perspective.
BACKGROUND
Body-fluid loss during prolonged continuous exercise can impair cardiovascular function, harming performance. Delta percent plasma volume (dPV) represents the change in central and circulatory body-water volume and therefore hydration during exercise; however, the effect of carbohydrate-electrolyte drinks and water on the dPV response is unclear.
OBJECTIVE
To determine by meta-analysis the effects of ingested hypertonic (> 300 mOsmol kg), isotonic (275-300 mOsmol kg) and hypotonic (< 275 mOsmol kg) drinks containing carbohydrate and electrolyte ([Na] < 50 mmol L), and non-carbohydrate drinks/water (< 40 mOsmol kg) on dPV during continuous exercise.
METHODS
A systematic review produced 28 qualifying studies and 68 drink treatment effects. Random-effects meta-analyses with repeated measures provided estimates of effects and probability of superiority (p) during 0-180 min of exercise, adjusted for drink osmolality, ingestion rate, metabolic rate and a weakly informative Bayesian prior.
RESULTS
Mean drink effects on dPV were: hypertonic - 7.4% [90% compatibility limits (CL) - 8.5, - 6.3], isotonic - 8.7% (90% CL - 10.1, - 7.4), hypotonic - 6.3% (90% CL - 7.4, - 5.3) and water - 7.5% (90% CL - 8.5, - 6.4). Posterior contrast estimates relative to the smallest important effect (dPV = 0.75%) were: hypertonic-isotonic 1.2% (90% CL - 0.1, 2.6; p = 0.74), hypotonic-isotonic 2.3% (90% CL 1.1, 3.5; p = 0.984), water-isotonic 1.3% (90% CL 0.0, 2.5; p = 0.76), hypotonic-hypertonic 1.1% (90% CL 0.1, 2.1; p = 0.71), hypertonic-water 0.1% (90% CL - 0.8, 1.0; p = 0.12) and hypotonic-water 1.1% (90% CL 0.1, 2.0; p = 0.72). Thus, hypotonic drinks were very likely superior to isotonic and likely superior to hypertonic and water. Metabolic rate, ingestion rate, carbohydrate characteristics and electrolyte concentration were generally substantial modifiers of dPV.
CONCLUSION
Hypotonic carbohydrate-electrolyte drinks ingested continuously during exercise provide the greatest benefit to hydration.
Topics: Bayes Theorem; Dehydration; Exercise; Humans; Osmolar Concentration; Sodium; Water-Electrolyte Balance
PubMed: 34716905
DOI: 10.1007/s40279-021-01558-y -
International Journal of Sport... Mar 2021CrossFit® is a high-intensity functional training method consisting of daily workouts called "workouts of the day." No nutritional recommendations exist for CrossFit®...
CrossFit® is a high-intensity functional training method consisting of daily workouts called "workouts of the day." No nutritional recommendations exist for CrossFit® that are supported by scientific evidence regarding the energetic demands of this type of activity or dietary and supplement interventions. This systematic review performed in accordance with PRISMA guidelines aimed to identify studies that determined (a) the physiological and metabolic demands of CrossFit® and (b) the effects of nutritional strategies on CrossFit® performance to guide nutritional recommendations for optimal recovery, adaptations, and performance for CrossFit® athletes and direct future research in this emerging area. Three databases were searched for studies that investigated physiological responses to CrossFit® and dietary or supplementation interventions on CrossFit® performance. Various physiological measures revealed the intense nature of all CrossFit® workouts of the day, reflected in substantial muscle fatigue and damage. Dietary and supplementation studies provided an unclear insight into effective strategies to improve performance and enhance adaptations and recovery due to methodological shortcomings across studies. This systematic review showed that CrossFit® is a high-intensity sport with fairly homogenous anaerobic and aerobic characteristics, resulting in substantial metabolic stress, leading to metabolite accumulation (e.g., lactate and hydrogen ions) and increased markers of muscle damage and muscle fatigue. Limited interventional data exist on dietary and supplementation strategies to optimize CrossFit® performance, and most are moderate to very low quality with some critical methodological limitations, precluding solid conclusions on their efficacy. High-quality work is needed to confirm the ideal dietary and supplemental strategies for optimal performance and recovery for CrossFit® athletes and is an exciting avenue for further research.
Topics: Athletic Performance; Biomedical Research; Diet; Dietary Supplements; Energy Metabolism; Forecasting; Heart Rate; Humans; Lactic Acid; Muscle Fatigue; Myalgia; Oxygen Consumption; Physical Conditioning, Human
PubMed: 33513565
DOI: 10.1123/ijsnem.2020-0223 -
Cell Death & Disease Feb 2023Sepsis is a life-threatening disorder disease defined as infection-induced dysregulated immune responses and multiple organ dysfunction. The imbalance between... (Review)
Review
Sepsis is a life-threatening disorder disease defined as infection-induced dysregulated immune responses and multiple organ dysfunction. The imbalance between hyperinflammation and immunosuppression is a crucial feature of sepsis immunity. Epigenetic modifications, including histone modifications, DNA methylation, chromatin remodeling, and non-coding RNA, play essential roles in regulating sepsis immunity through epi-information independent of the DNA sequence. In recent years, the mechanisms of histone modification in sepsis have received increasing attention, with ongoing discoveries of novel types of histone modifications. Due to the capacity for prolonged effects on immune cells, histone modifications can induce immune cell reprogramming and participate in the long-term immunosuppressed state of sepsis. Herein, we systematically review current mechanisms of histone modifications involved in the regulation of sepsis, summarize their role in sepsis from an immune perspective and provide potential therapeutic opportunities targeting histone modifications in sepsis treatment.
Topics: Humans; Histones; Histone Code; Epigenesis, Genetic; Sepsis; DNA Methylation
PubMed: 36774341
DOI: 10.1038/s41419-023-05656-9 -
British Journal of Sports Medicine Aug 2023To determine and compare the dose-response effects of exercise and caloric restriction on visceral adipose tissue in overweight and obese adults, while controlling for... (Meta-Analysis)
Meta-Analysis Review
Dose-response effects of exercise and caloric restriction on visceral adiposity in overweight and obese adults: a systematic review and meta-analysis of randomised controlled trials.
OBJECTIVE
To determine and compare the dose-response effects of exercise and caloric restriction on visceral adipose tissue in overweight and obese adults, while controlling for the weekly energy deficit induced by the interventions.
METHODS
PubMed, Embase, CINAHL and Web of Science were searched for randomised controlled trials comparing exercise or caloric restriction against eucaloric controls in overweight or obese adults. The primary outcome was the change in visceral fat measured by CT or MRI. Meta-analyses and meta-regressions were performed to determine the overall effect size (ES) and the dose-dependent relationship of exercise and caloric restriction on visceral fat. Heterogeneity, risk of bias and the certainty of evidence were also assessed.
RESULTS
Forty randomised controlled trials involving 2190 participants were included. Overall, exercise (ES -0.28 (-0.37 to -0.19); p<0.001; I=25%) and caloric restriction (ES -0.53 (-0.71 to -0.35); p<0.001; I=33%) reduced visceral fat compared with the controls. Exercise demonstrated a dose-response effect of -0.15 ((-0.23 to -0.07); p<0.001) per 1000 calories deficit per week, whereas the effect of caloric restriction was not dose-dependent (ES 0.03 (-0.12 to 0.18); p=0.64). Most of the studies showed a moderate risk of bias.
CONCLUSIONS
These findings support the dose-dependent effects of exercise to reduce visceral fat in overweight and obese adults. Caloric restriction did not demonstrate a dose-response relationship, although this may be attributed to the smaller number of studies available for analysis, compared with exercise studies.
PROSPERO REGISTRATION NUMBER
CRD42020210096.
Topics: Adult; Humans; Overweight; Adiposity; Obesity; Exercise; Intra-Abdominal Fat; Randomized Controlled Trials as Topic
PubMed: 36669870
DOI: 10.1136/bjsports-2022-106304