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International Journal of Sport... Mar 2023Whether caffeine (CAF) increases fat metabolism remains debatable. Using systematic review coupled with meta-analysis, our aim was to determine effects of CAF on fat... (Meta-Analysis)
Meta-Analysis
Whether caffeine (CAF) increases fat metabolism remains debatable. Using systematic review coupled with meta-analysis, our aim was to determine effects of CAF on fat metabolism and the relevant factors moderating this effect. Electronic databases PubMed, SPORTDiscus, and Web of Science were searched using the following string: CAF AND (fat OR lipid) AND (metabolism OR oxidation). A meta-analytic approach aggregated data from 94 studies examining CAF's effect on fat metabolism assessed by different biomarkers. The overall effect size (ES) was 0.39 (95% confidence interval [CI] [0.30, 0.47], p < .001), indicating a small effect of CAF to increase fat metabolism; however, ES was significantly higher (p < .001) based on blood biomarkers (e.g., free fatty acids, glycerol) (ES = 0.55, 95% CI [0.43, 0.67]) versus expired gas analysis (respiratory exchange ratio, calculated fat oxidation) (ES = 0.26, 95% CI [0.16, 0.37]), although both were greater than zero. Fat metabolism increased to a greater extent (p = .02) during rest (ES = 0.51, 95% CI [0.41, 0.62]) versus exercise (ES = 0.35, 95% CI [0.26, 0.44]) across all studies, although ES was not different for studies reporting both conditions (ES = 0.49 and 0.44, respectively). There were no subgroup differences based on participants' fitness level, sex, or CAF dosage. CAF ingestion increases fat metabolism but is more consistent with blood biomarkers versus whole-body gas exchange measures. CAF has a small effect during rest across all studies, although similar to exercise when compared within the same study. CAF dosage did not moderate this effect.
Topics: Humans; Caffeine; Exercise; Lipid Metabolism; Oxidation-Reduction
PubMed: 36495873
DOI: 10.1123/ijsnem.2022-0131 -
Molecular Psychiatry Mar 2012A comprehensive literature search was performed to collate evidence of mitochondrial dysfunction in autism spectrum disorders (ASDs) with two primary objectives. First,... (Meta-Analysis)
Meta-Analysis Review
A comprehensive literature search was performed to collate evidence of mitochondrial dysfunction in autism spectrum disorders (ASDs) with two primary objectives. First, features of mitochondrial dysfunction in the general population of children with ASD were identified. Second, characteristics of mitochondrial dysfunction in children with ASD and concomitant mitochondrial disease (MD) were compared with published literature of two general populations: ASD children without MD, and non-ASD children with MD. The prevalence of MD in the general population of ASD was 5.0% (95% confidence interval 3.2, 6.9%), much higher than found in the general population (≈ 0.01%). The prevalence of abnormal biomarker values of mitochondrial dysfunction was high in ASD, much higher than the prevalence of MD. Variances and mean values of many mitochondrial biomarkers (lactate, pyruvate, carnitine and ubiquinone) were significantly different between ASD and controls. Some markers correlated with ASD severity. Neuroimaging, in vitro and post-mortem brain studies were consistent with an elevated prevalence of mitochondrial dysfunction in ASD. Taken together, these findings suggest children with ASD have a spectrum of mitochondrial dysfunction of differing severity. Eighteen publications representing a total of 112 children with ASD and MD (ASD/MD) were identified. The prevalence of developmental regression (52%), seizures (41%), motor delay (51%), gastrointestinal abnormalities (74%), female gender (39%), and elevated lactate (78%) and pyruvate (45%) was significantly higher in ASD/MD compared with the general ASD population. The prevalence of many of these abnormalities was similar to the general population of children with MD, suggesting that ASD/MD represents a distinct subgroup of children with MD. Most ASD/MD cases (79%) were not associated with genetic abnormalities, raising the possibility of secondary mitochondrial dysfunction. Treatment studies for ASD/MD were limited, although improvements were noted in some studies with carnitine, co-enzyme Q10 and B-vitamins. Many studies suffered from limitations, including small sample sizes, referral or publication biases, and variability in protocols for selecting children for MD workup, collecting mitochondrial biomarkers and defining MD. Overall, this evidence supports the notion that mitochondrial dysfunction is associated with ASD. Additional studies are needed to further define the role of mitochondrial dysfunction in ASD.
Topics: Adenosine Triphosphate; Adolescent; Animals; Biomarkers; Brain; Child; Child Development Disorders, Pervasive; Comorbidity; Developmental Disabilities; Disease Models, Animal; Electron Transport; Energy Metabolism; Female; Gastrointestinal Diseases; Humans; Lactates; Male; Mitochondria; Mitochondrial Diseases; Neuroimaging; Prevalence; Pyruvic Acid; Seizures; Sex Distribution; Young Adult
PubMed: 21263444
DOI: 10.1038/mp.2010.136 -
Actas Dermo-sifiliograficas May 2017Actinic keratosis is a precursor lesion to the most common nonmelanoma skin cancer. Conventional photodynamic therapy (PDT) has been shown to be effective, but the... (Meta-Analysis)
Meta-Analysis Review
Actinic keratosis is a precursor lesion to the most common nonmelanoma skin cancer. Conventional photodynamic therapy (PDT) has been shown to be effective, but the procedure is time-consuming, can be very painful, and requires infrastructure. These shortcomings led to the emergence of daylight PDT. To obtain a global estimate of efficacy, we undertook a systematic literature review and performed a meta-analysis of the available evidence on the efficacy and safety of daylight PDT as compared to conventional PDT in the treatment of actinic keratosis and/or field cancerization. The conclusion is that the difference in efficacy is clinically negligible (global estimate of the mean response rate difference, -3.69%; 95% CI, -6.54% to -0.84%). The adverse effects of daylight PDT are mild and localized (79% of patients report no discomfort), and patients report less pain (P<.001). Daylight PDT gives good to excellent cosmetic results in more than 90% of patients, and patient satisfaction is greater (P<.001).
Topics: Carcinoma, Squamous Cell; Clinical Trials, Phase III as Topic; Esthetics; Humans; Keratosis, Actinic; Neoplasms, Radiation-Induced; Oxidation-Reduction; Pain; Patient Satisfaction; Photochemistry; Photochemotherapy; Photosensitizing Agents; Randomized Controlled Trials as Topic; Sunlight; Ultraviolet Rays
PubMed: 28063524
DOI: 10.1016/j.ad.2016.09.020 -
Molecules (Basel, Switzerland) Jan 2023We provide a systematic overview of the mechanochemical reactions of inorganic solids, notably simple binary compounds, such as oxides, nitrides, carbides, sulphides,... (Review)
Review
We provide a systematic overview of the mechanochemical reactions of inorganic solids, notably simple binary compounds, such as oxides, nitrides, carbides, sulphides, phosphides, hydrides, borides, borane derivatives, and related systems. Whereas the solid state has been traditionally considered to be of little synthetic value by the broader community of synthetic chemists, the solid-state community, and in particular researchers focusing on the reactions of inorganic materials, have thrived in building a rich and dynamic research field based on mechanically-driven transformations of inorganic substances typically seen as inert and high-melting. This review provides an insight into the chemical richness of such mechanochemical reactions and, at the same time, offers their tentative categorisation based on transformation type, resulting in seven distinct groupings: () the formation of adducts, () the reactions of dehydration; () oxidation-reduction (redox) reactions; () metathesis (or exchange) reactions; () doping and structural rearrangements, including reactions involving the reaction vessel (the milling jar); () acid-base reactions, and () other, mixed type reactions. At the same time, we offer a parallel description of inorganic mechanochemical reactions depending on the reaction conditions, as those that: () take place under mild conditions (e.g., manual grinding using a mortar and a pestle); () proceed gradually under mechanical milling; () are self-sustained and initiated by mechanical milling, i.e., mechanically induced self-propagating reactions (MSRs); and () proceed only via harsh grinding and are a result of chemical reactivity under strongly non-equilibrium conditions. By elaborating on typical examples and general principles in the mechanochemistry of hard and high-melting substances, this review provides a suitable complement to the existing literature, focusing on the properties and mechanochemical reactions of inorganic solids, such as nanomaterials and catalysts.
Topics: Catalysis; Nanostructures; Oxidation-Reduction; Oxides
PubMed: 36677953
DOI: 10.3390/molecules28020897 -
NeuroImage. Clinical 2023Aging is characterized by a gradual decline of the body's biological functions, which can lead to increased production of reactive oxygen species (ROS). Antioxidants... (Review)
Review
Aging is characterized by a gradual decline of the body's biological functions, which can lead to increased production of reactive oxygen species (ROS). Antioxidants neutralize ROS and maintain balance between oxidation and reduction. If ROS production exceeds the ability of antioxidant systems to neutralize, a damaging state of oxidative stress (OS) may exist. The reduced form of glutathione (GSH) is the most abundant antioxidant, and decline of GSH is considered a marker of OS. Our review summarizes the literature on GSH variations with age in healthy adults in brain (in vivo, ex vivo) and blood (plasma, serum), and reliability of in vivo magnetic resonance spectroscopy (MRS) measurement of GSH. A systematic PubMed search identified 35 studies. All in vivo MRS studies (N = 13) reported good to excellent reproducibility of GSH measures. In brain, 3 out of 4 MRS studies reported decreased GSH with age, measured in precuneus, cingulate, and occipital regions, while 1 study reported increased GSH with age in frontal and sensorimotor regions. In post-mortem brain, out of 3 studies, 2 reported decreased GSH with age in hippocampal and frontal regions, while 1 study reported increased GSH with age in a frontal region. Oxidized glutathione disulfide (GSSG) was reported to be increased in caudate with age in 1 study, suggesting OS. Although findings in the brain lacked a clear consensus, the majority of studies suggested a decline of GSH with age. The low number of studies (particularly ex vivo) and potential regional differences may have contributed to variability in the findings in brain. In blood, in contrast, GSH levels predominately were reported to decrease with advancing age (except in the oldest-old, who may represent a select group of particularly successful agers), while GSSG findings lacked consensus. The larger number of studies assessing age-specific GSH level changes in blood (N = 16) allowed for more robust consensus across studies than in brain. Overall, the literature suggests that aging is associated with increased OS in brain and body, but the timing and regional distribution of changes in the brain require further study. The contribution of brain OS to brain aging, and the effect of interventions to raise brain GSH levels on decline of brain function, remain understudied. Given that reliable tools to measure brain GSH exist, we hope this paper will serve as a catalyst to stimulate more work in this field.
Topics: Humans; Adult; Aged, 80 and over; Antioxidants; Glutathione Disulfide; Reproducibility of Results; Reactive Oxygen Species; Glutathione; Brain
PubMed: 37742519
DOI: 10.1016/j.nicl.2023.103503 -
Respiratory Research Nov 2016Chronic obstructive pulmonary disease (COPD) is a progressive condition characterized by airflow limitation associated with an abnormal inflammatory response of the... (Review)
Review
Chronic obstructive pulmonary disease (COPD) is a progressive condition characterized by airflow limitation associated with an abnormal inflammatory response of the lungs to noxious particles and gases, caused primarily by cigarette smoking. Increased oxidative burden plays an important role in the pathogenesis of COPD. There is a delicate balance between the toxicity of oxidants and the protective function of the intracellular and extracellular antioxidant defense systems, which is critically important for the maintenance of normal pulmonary functions. Several biomarkers of oxidative stress are available and have been evaluated in COPD. In this review, we summarize the main literature findings about circulating oxidative stress biomarkers, grouped according to their method of detection, measured in COPD subjects.
Topics: Animals; Biomarkers; Cell-Free Nucleic Acids; DNA; DNA Damage; Humans; Lipid Peroxidation; Lipid Peroxides; Oxidative Stress; Predictive Value of Tests; Prognosis; Protein Carbonylation; Pulmonary Disease, Chronic Obstructive; Reactive Oxygen Species; Risk Factors; Smoking
PubMed: 27842552
DOI: 10.1186/s12931-016-0471-z -
BioMed Research International 2014Oxidative stress plays an important role in the pathogenesis of Alzheimer's disease (AD). This paper aims to examine whether biomarkers of oxidative stress and... (Review)
Review
PURPOSE
Oxidative stress plays an important role in the pathogenesis of Alzheimer's disease (AD). This paper aims to examine whether biomarkers of oxidative stress and antioxidants could be useful biomarkers in AD, which might form the bases of future clinical studies.
METHODS
PubMed, SCOPUS, and Web of Science were systematically queried to obtain studies with available data regarding markers of oxidative stress and antioxidants from subjects with AD.
RESULTS AND CONCLUSION
Although most studies show elevated serum markers of lipid peroxidation in AD, there is no sufficient evidence to justify the routine use of biomarkers as predictors of severity or outcome in AD.
Topics: Alzheimer Disease; Animals; Antioxidants; Biomarkers; Humans; Lipid Peroxidation; Oxidative Stress; PubMed
PubMed: 24949424
DOI: 10.1155/2014/182303 -
Nutrients Nov 2020Liver lipid accumulation is a hallmark of non-alcoholic fatty liver disease (NAFLD), broadly associated with insulin resistance. Inositols (INS) are ubiquitous polyols...
Liver lipid accumulation is a hallmark of non-alcoholic fatty liver disease (NAFLD), broadly associated with insulin resistance. Inositols (INS) are ubiquitous polyols implied in many physiological functions. They are produced endogenously, are present in many foods and in dietary supplements. Alterations in INS metabolism seems to play a role in diseases involving insulin resistance such as diabetes and polycystic ovary syndrome. Given its role in other metabolic syndromes, the hypothesis of an INS role as a supplement in NAFLD is intriguing. We performed a systematic review of the literature to find preclinical and clinical evidence of INS supplementation efficacy in NAFLD patients. We retrieved 10 studies on animal models assessing Myoinosiol or Pinitol deficiency or supplementation and one human randomized controlled trial (RCT). Overall, INS deficiency was associated with increased fatty liver in animals. Conversely, INS supplementation in animal models of fatty liver reduced hepatic triglycerides and cholesterol accumulation and maintained a normal ultrastructural liver histopathology. In the one included RCT, Pinitol supplementation obtained similar results. Pinitol significantly reduced liver fat, post-prandial triglycerides, AST levels, lipid peroxidation increasing glutathione peroxidase activity. These results, despite being limited, indicate the need for further evaluation of INS in NAFLD in larger clinical trials.
Topics: Animals; Cholesterol; Dietary Supplements; Female; Glutathione Peroxidase; Humans; Inositol; Insulin Resistance; Lipid Peroxidation; Liver; Male; Non-alcoholic Fatty Liver Disease; Postprandial Period; Randomized Controlled Trials as Topic; Treatment Outcome; Triglycerides
PubMed: 33153126
DOI: 10.3390/nu12113379 -
Molecules (Basel, Switzerland) Sep 2014Chronic diseases such as cancer, diabetes, neurodegenerative and cardiovascular diseases are characterized by an enhanced state of oxidative stress, which may result... (Review)
Review
Chronic diseases such as cancer, diabetes, neurodegenerative and cardiovascular diseases are characterized by an enhanced state of oxidative stress, which may result from the overproduction of reactive species and/or a decrease in antioxidant defenses. The search for new chemical entities with antioxidant profile is still thus an emerging field on ongoing interest. Due to the lack of reviews concerning the antioxidant activity of lichen-derived natural compounds, we performed a review of the antioxidant potential and mechanisms of action of natural compounds isolated from lichens. The search terms "lichens", "antioxidants" and "antioxidant response elements" were used to retrieve articles in LILACS, PubMed and Web of Science published until February 2014. From a total of 319 articles surveyed, 32 met the established inclusion and exclusion criteria. It was observed that the most common isolated compound studied was usnic acid, cited in 14 out of the 32 articles. The most often described antioxidant assays for the study of in vitro antioxidant activity were mainly DPPH, LPO and SOD. The most suggested mechanisms of action were scavenging of reactive species, enzymatic activation and inhibition of iNOS. Thus, compounds isolated from lichens are possible candidates for the management of oxidative stress, and may be useful in the treatment of chronic diseases.
Topics: Antioxidant Response Elements; Antioxidants; Benzofurans; Biphenyl Compounds; Free Radical Scavengers; Humans; Lichens; Neoplasms; Oxidation-Reduction; Oxidative Stress; Picrates
PubMed: 25221871
DOI: 10.3390/molecules190914496 -
Scientific Reports Feb 2017Myocardial ischemia reperfusion injury is a negative pathophysiological event that may result in cardiac cell apoptosis and is a result of coronary revascularization and... (Meta-Analysis)
Meta-Analysis Review
Myocardial ischemia reperfusion injury is a negative pathophysiological event that may result in cardiac cell apoptosis and is a result of coronary revascularization and cardiac intervention procedures. The resulting loss of cardiomyocyte cells and the formation of scar tissue, leads to impaired heart function, a major prognostic determinant of long-term cardiac outcomes. Photobiomodulation is a novel cardiac intervention that has displayed therapeutic effects in reducing myocardial ischemia reperfusion related myocardial injury in animal models. A growing body of evidence supporting the use of photobiomodulation in myocardial infarct models has implicated multiple molecular interactions. A systematic review was conducted to identify the strength of the evidence for the therapeutic effect of photobiomodulation and to summarise the current evidence as to its mechanisms. Photobiomodulation in animal models showed consistently positive effects over a range of wavelengths and application parameters, with reductions in total infarct size (up to 76%), decreases in inflammation and scarring, and increases in tissue repair. Multiple molecular pathways were identified, including modulation of inflammatory cytokines, signalling molecules, transcription factors, enzymes and antioxidants. Current evidence regarding the use of photobiomodulation in acute and planned cardiac intervention is at an early stage but is sufficient to inform on clinical trials.
Topics: Animals; Antioxidants; Bias; Biomarkers; Cytokines; Cytoskeleton; Dose-Response Relationship, Radiation; Humans; Inflammation Mediators; Intercellular Signaling Peptides and Proteins; Low-Level Light Therapy; Mitochondria; Myocardial Reperfusion Injury; Oxidation-Reduction; Risk; Signal Transduction; Time Factors
PubMed: 28181487
DOI: 10.1038/srep42386