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Foods (Basel, Switzerland) May 2022This study adopted systematic literature review and meta-analysis methodology to explored anti-oxidative effect of pu-erh tea. Study authors have systemically searched... (Review)
Review
This study adopted systematic literature review and meta-analysis methodology to explored anti-oxidative effect of pu-erh tea. Study authors have systemically searched seven databases up until 21 February 2020. In performing the literature search on the above-mentioned databases, the authors used keywords of pu-erh AND (superoxide dismutase OR glutathione peroxidase OR malondialdehyde). Results derived from meta-analyses showed statistically significant effects of pu-erh tea on reducing serum MDA levels (SMD, −4.19; 95% CI, −5.22 to −3.15; p < 0.001; I2 = 93.67%); increasing serum SOD levels (SMD, 2.41; 95% CI, 1.61 to 3.20; p < 0.001; I2 = 91.36%); and increasing serum GSH-Px levels (SMD, 4.23; 95% CI, 3.10 to 5.36; p < 0.001; I2 = 93.69%). Results from systematic review and meta-analyses validated that various ingredients found in pu-erh tea extracts had anti-oxidation effects, a long-held conventional wisdom with limited supporting evidence.
PubMed: 35564056
DOI: 10.3390/foods11091333 -
Free Radical Biology & Medicine May 2012Autism spectrum disorders (ASDs) are rarely diagnosed in children younger than 2 years, because diagnosis is based entirely on behavioral tests. Oxidative damage may... (Meta-Analysis)
Meta-Analysis Review
Autism spectrum disorders (ASDs) are rarely diagnosed in children younger than 2 years, because diagnosis is based entirely on behavioral tests. Oxidative damage may play a central role in this pathogenesis, together with the interconnected transmethylation cycle and transsulfuration pathway. In an attempt to clarify and quantify the relationship between oxidative stress-related blood biomarkers and ASDs, a systematic literature review was carried out. For each identified study, mean biomarker levels were compared in cases and controls providing a point estimate, the mean ratio, for each biomarker. After meta-analysis, the ASD patients showed decreased blood levels of reduced glutathione (27%), glutathione peroxidase (18%), methionine (13%), and cysteine (14%) and increased concentrations of oxidized glutathione (45%) relative to controls, whereas superoxide dismutase, homocysteine, and cystathionine showed no association with ASDs. For the C677T allele in the methylene tetrahydrofolate reductase gene (MTHFR), homozygous mutant subjects (TT) showed a meta-OR of 2.26 (95% CI 1.30-3.91) of being affected by ASD with respect to the homozygous nonmutant (CC). Case-control studies on blood levels of vitamins suggest a lack of association (folic acid and vitamin B12) or rare association (vitamins A, B6, C, D, E). Sparse results were available for other biomarkers (ceruloplasmin, catalase, cysteinylglycine, thiobarbituric acid-reactive substances, nitric oxide) and for polymorphisms in other genes. Existing evidence is heterogeneous and many studies are limited by small sample size and effects. In conclusion, existing evidence suggests a role for glutathione metabolism, the transmethylation cycle, and the transsulfuration pathway, although these findings should be interpreted with caution, and larger, more standardized studies are warranted.
Topics: Biomarkers; Child; Child Development Disorders, Pervasive; Child, Preschool; Glutathione; Humans; Methylenetetrahydrofolate Reductase (NADPH2); Oxidative Stress; Vitamins
PubMed: 22542447
DOI: 10.1016/j.freeradbiomed.2012.03.011 -
Journal of Ophthalmology 2019To systematically evaluate the associations between oxidative stress status and different types of glaucoma. (Review)
Review
PURPOSE
To systematically evaluate the associations between oxidative stress status and different types of glaucoma.
DESIGN
Systematic review and meta-analysis.
METHODS
We searched PubMed, EMBASE, and the Web of Science for randomized controlled trials written in the English language between January 1, 1990, and November 30, 2016. A random effects model was used to estimate oxidative stress status along with weighted mean differences and 95% confidence intervals (CIs). A funnel plot analysis and Egger's test were performed to assess potential publication bias.
MAIN OUTCOME MEASURES
Oxidative stress status was abnormal and different in patients with OAG (open-angle glaucoma) and EXG (exfoliation glaucoma).
RESULTS
Blood TAS (total antioxidant status) was lower in the OAG group than in the control group, with a mean difference of 0.580 mmol/L ( < 0.0001, 95% CI = -0.668 to -0.492). The aqueous humor SOD (superoxide dismutase), GPX (glutathione peroxidase), and CAT (catalase) levels were higher in the OAG group than in the control group, with mean differences of 17.989 U/mL ( < 0.0001, 95% CI = 14.579-21.298), 12.441 U/mL ( < 0.0001, 95% CI = 10.423-14.459), and 1.229 fmol/mL (=0.042, 95% CI = 0.043-2.414), respectively. Blood TAS was lower in the EXG group than in the control group, with a mean difference of 0.262 mmol/L ( < 0.0001, 95% CI = -0.393 to -0.132). However, there were no differences in blood TOS and aqueous humor TOS between the EXG group and the control group.
CONCLUSIONS
This meta-analysis indicates that OAG patients had a lower TAS in the blood and higher levels of SOD, GPX, and CAT in the aqueous humor, while EXG patients only had a decreased TAS in the blood.
PubMed: 30766729
DOI: 10.1155/2019/1803619 -
Tumour Biology : the Journal of the... Jan 2014Reactive oxygen species-related damage plays a critical role in carcinogenesis. Glutathione peroxidase 1 (GPX1) and mitochondrial superoxide dismutase (MnSOD) are two... (Meta-Analysis)
Meta-Analysis Review
Reactive oxygen species-related damage plays a critical role in carcinogenesis. Glutathione peroxidase 1 (GPX1) and mitochondrial superoxide dismutase (MnSOD) are two key antioxidant enzymes in the defense system against reactive oxygen species. This systematic review and meta-analysis was designed to evaluate the association of single-nucleotide polymorphisms in GPX1 and MnSOD genes with susceptibility to bladder cancer risk. Online databases of PubMed, Embase, China National Knowledge Infrastructure, and SinoMed were searched to identify eligible studies. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated to estimated the association strength. The fixed effects model and random effects model were used to pool the data from different studies. By pooling all eligible studies, we found that the GPX1 Pro198Leu polymorphism was associated with a significantly increased risk of bladder cancer (Leu vs. Pro, OR = 2.111, 95% CI = 1.020-4.368, heterogeneity (p < 0.001); LeuPro/LeuLeu vs. ProPro, OR = 1.876, 95% CI = 1.011-3.480, heterogeneity (p < 0.001)). No significant association of MnSOD Ala-9Val polymorphism with cancer risk was observed (AlaVal/ValVal vs. AlaAla, OR = 0.966, 95% CI = 0.754-1.239, heterogeneity (p = 0.390); Vla vs. Ala, OR = 1.038, 95% CI = 0.782-1.377, heterogeneity (p = 0.015)). This systematic review and meta-analysis demonstrated that the GPX1 Pro198Leu polymorphism significantly increased susceptibility to bladder cancer, while the MnSOD Ala-9Val polymorphism was not associated with bladder cancer risk.
Topics: Alleles; Case-Control Studies; Codon; Genetic Predisposition to Disease; Glutathione Peroxidase; Humans; Odds Ratio; Polymorphism, Single Nucleotide; Superoxide Dismutase; Urinary Bladder Neoplasms; Glutathione Peroxidase GPX1
PubMed: 24037914
DOI: 10.1007/s13277-013-1103-6 -
Frontiers in Physiology 2022The dynamic balance between oxidation and anti-oxidation in the body's internal environment has a significant meaning for human health. Physical exercise and... (Review)
Review
Effect of Physical Exercise Under Different Intensity and Antioxidative Supplementation for Plasma Superoxide Dismutase in Healthy Adults: Systematic Review and Network Meta-Analysis.
BACKGROUND
The dynamic balance between oxidation and anti-oxidation in the body's internal environment has a significant meaning for human health. Physical exercise and antioxidative supplementation could affect the balance of oxidation and anti-oxidation systems. The evidence on the effects of physical exercise and antioxidative supplementation is mixed.
AIMS
To identify the effects of physical exercise, antioxidative supplementation, and their combination on the dynamic balance between oxidation and anti-oxidation in different subgroups of healthy adults.
METHODS
All studies which reported randomized controlled trials with healthy participants were screened and included from the databases of PubMed, Medline, Embase, and Ovid. All participants were reclassified according to their different daily life activities. All physical exercise interventions were reclassified according to the intensity. The effect size would be calculated in percent or factor units from the mean level change with its associated random-effect variance.
RESULT
There were 27 studies included in this review. The agreement between authors by using The Cochrane Collaboration Risk of Bias Assessment Tool reached a kappa-value of 0.72. Maintaining a regular physical exercise routine in an appropriate intensity would be beneficial to the body's anti-oxidative potential. Anti-oxidative supplementation could have some positive but limited effects on the body's anti-oxidative status and complex interaction with physical exercise.
CONCLUSION
Keeping a regular physical exercise routine and gradually increasing its intensity according to the individual's daily life activity might be a better choice to maintain and enhancing the body's antioxidation potential, only using anti-oxidative supplementation is not recommended. More research is needed to explore the best combination protocol.
REGISTRATION NUMBER
CRD42021241995.
PubMed: 35185608
DOI: 10.3389/fphys.2022.707176 -
Critical Reviews in Food Science and... 2020Vitamin D deficiency is considered a global public health problem with high prevalence in children and adolescents. The majority of the studies in the literature have...
Vitamin D deficiency is considered a global public health problem with high prevalence in children and adolescents. The majority of the studies in the literature have identified a relationship between vitamin D insufficiency/deficiency and obesity, as well as other traditional cardiometabolic risk factors in children and adolescents. Scarce studies address vitamin D status with oxidative stress and inflammation in the young population. The aim of this systematic review was to evaluate the evidence of the association of vitamin D status with oxidative stress and inflammation in children and adolescents. This is a systematic review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guideline on reporting systematic reviews. Eight studies were selected for this review. All included studies evaluated inflammatory biomarkers and two out of eight evaluated biomarkers of oxidative stress. The majority of the studies (five out of eight) found association of vitamin D status with biomarkers of oxidative stress and inflammation such as C-reactive protein (CRP), interleukin-6 (IL-6), cathepsin S, vascular cell adhesion molecule-1 (VCAM-1), malondialdehyde (MDA), myeloperoxidase, 3-nitrotyrosine, and superoxide dismutase (SOD). Vitamin D status is associated with oxidative stress and inflammation in the majority of the studies with children and adolescents. Thus, the assessment of vitamin D status is important because it is associated with nontraditional cardiometabolic markers in the pediatric population (review registration: PROSPERO CRD42018109307).
Topics: Adolescent; Biomarkers; Child; Humans; Inflammation; Oxidative Stress; Vitamin D; Vitamin D Deficiency; Vitamins
PubMed: 30596263
DOI: 10.1080/10408398.2018.1546671 -
Food & Function May 2022Quercetin, a flavonoid possessing numerous biological activities, is reported to improve renal injury in diabetic animals. Here, the aim of this systematic review and... (Meta-Analysis)
Meta-Analysis Review
Quercetin, a flavonoid possessing numerous biological activities, is reported to improve renal injury in diabetic animals. Here, the aim of this systematic review and meta-analysis is to assess the effect of quercetin on diabetic nephropathy and summarize its possible mechanisms. We searched in four databases PubMed, Web of Sciences (WOS), Cochrane and Embase from inception to May 2021 and ultimately included 20 animal studies in this review. A total of 12 outcome measurements including renal function indexes, oxidative stress biomarkers and inflammatory cytokines were extracted for meta-analysis using RevMan 5.4 software. Apart from creatinine clearance and uric acid with no significant difference, quercetin significantly decreased the levels of renal index, serum/plasma creatinine (SCr), blood urea nitrogen (BUN), urine protein, urine albumin, malondialdehyde (MDA), tumor necrosis factor (TNF)-α and interleukin (IL)-1β, and increased superoxide dismutase (SOD) and catalase (CAT) activity. In short, quercetin improves renal function and attenuates the renal oxidative stress level and inflammatory response in DN animal models. Its possible action mechanisms include anti-oxidation, anti-inflammation, anti-fibrosis, and regulation of renal lipid accumulation.
Topics: Animals; Antioxidants; Creatinine; Diabetes Mellitus; Diabetic Nephropathies; Female; Humans; Kidney; Male; Oxidative Stress; Quercetin
PubMed: 35416188
DOI: 10.1039/d1fo03958j -
Frontiers in Pharmacology 2019Rhein is considered to have beneficial influence on diabetic nephropathy. Animal experiments suggested that the mechanisms of rhein against diabetic nephropathy may...
Rhein is considered to have beneficial influence on diabetic nephropathy. Animal experiments suggested that the mechanisms of rhein against diabetic nephropathy may involve many processes, but the credibility of the evidence is unclear. Therefore, we conducted systematic review and meta-analysis of pre-clinical animal data to assess the current evidence for rhein effects and mechanisms in treating diabetic nephropathy. The databases of PubMed, EMBASE, Web of Science, China National Knowledge Infrastructure, VIP information database, Wanfang Data Information Site, and Chinese Biomedical Literature were searched for this review. SYRCLE's risk of bias tool for animal studies was applied to assess the methodological quality of studies. A meta-analysis was performed according to the Cochrane Handbook for Systematic Reviews of Interventions by using RevMan 5.3 and STATA/SE 12.0 software. This study was registered with PROSPERO, number CRD42018105220. Twenty-five studies involving 537 animals were included. There was significant association of rhein with levels of blood glucose ( < 0.05), serum creatinine (Scr) ( < 0.05), urine protein ( < 0.05), kidney tubules injury index ( < 0.05), relative area of kidney collagen ( < 0.05), transforming growth factor-β ( < 0.05), malondialdehyde ( < 0.05), and superoxide dismutase ( < 0.05) compared with that in the control group. No significant association between rhein and endothelin ( > 0.05) was found. Subgroup analysis showed that the hypoglycemic effect of rhein on type 2 diabetic nephropathy was better than on type 1 diabetic nephropathy ( < 0.05). These findings suggested that rhein has beneficial effects on animal models of diabetic nephropathy, and that the mechanisms are mostly involved with ameliorating levels of TGF-β, renal fibrosis, metabolism, and oxidative stress status. However, some factors such as possible publication bias, methodological quality, and sample size may affect the accuracy of positive findings. These limitations suggested that a cautious interpretation of the positive results of this systematic review and meta-analysis is necessary. Therefore, high methodological quality and well-reported animal experiments are needed in future research.
PubMed: 31920660
DOI: 10.3389/fphar.2019.01473 -
Medical Science Monitor : International... Mar 2019BACKGROUND This systematic review of the literature and meta-analysis aimed to review the evaluation and monitoring of superoxide dismutase (SOD) activity and its... (Meta-Analysis)
Meta-Analysis
BACKGROUND This systematic review of the literature and meta-analysis aimed to review the evaluation and monitoring of superoxide dismutase (SOD) activity and its clinical significance in gastric cancer. MATERIAL AND METHODS Systematic review involved searching the PubMed, Embase, Ovid, and the China National Knowledge Infrastructure (CNKI) databases. Search terms included 'superoxide dismutase,' and 'gastric cancer.' Studies that included measurements of SOD activity in peripheral blood samples in patients with SOD activity compared with healthy controls. The study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. RESULTS Ten controlled clinical studies were identified that included six studies that measured SOD in serum, three in erythrocytes, and one study that measured SOD on whole blood. Meta-analysis, using the standardized mean difference (SMD) and the 95% confidence interval (CI), showed that patients with gastric cancer had significantly decreased SOD activity when compared with the healthy controls (SMD, -0.840; 95% CI, -1.463 to -0.218; p=0.008). Subgroup analysis was conducted on SOD distribution in the blood (erythrocyte: SMD, -1.773; 95% CI, -2.504 to -1.042; p=0.000) (serum SMD, -0.322; 95% CI, -1.006-0.361; p=0.355) (whole blood: SMD, -1.251; 95% CI, -1.731 to -0.771; p=0.000) and for male subjects (SMD, -2.090; 95% CI, -2.725 to -1.456; p<0.001). CONCLUSIONS Meta-analysis showed that SOD measurements from blood samples, especially in erythrocytes, had potential as a diagnostic and monitoring parameter in patients with gastric cancer.
Topics: Biomarkers, Tumor; Female; Humans; Male; Stomach Neoplasms; Superoxide Dismutase; Superoxide Dismutase-1
PubMed: 30886134
DOI: 10.12659/MSM.913375 -
Journal of Neurology, Neurosurgery, and... Jun 2011The population rate of familial amyotrophic lateral sclerosis (FALS) is frequently reported as 10%. However, a systematic review and meta-analysis of the true population... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The population rate of familial amyotrophic lateral sclerosis (FALS) is frequently reported as 10%. However, a systematic review and meta-analysis of the true population based frequency of FALS has never been performed.
METHOD
A Medline literature review identified all original articles reporting a rate of FALS. Studies were grouped according to the type of data presented and examined for sources of case ascertainment. A systematic review and meta-analysis of reported rates of FALS was then conducted to facilitate comparison between studies and calculate a pooled rate of FALS.
RESULTS
38 papers reported a rate of FALS. Thirty-three papers were included in analysis and the rate of FALS for all studies was 4.6% (95% CI 3.9% to 5.5%). Restricting the analysis to prospective population based registry data revealed a rate of 5.1% (95% CI 4.1% to 6.1%). The incidence of FALS was lower in southern Europe. There was no correlation between rate of FALS and reported SOD1 mutation rates.
CONCLUSION
The rate of FALS among prospective population based registries is 5.1% (CI 4.1 to 6.1%), and not 10% as is often stated. Further detailed prospective population based studies of familial ALS are required to confirm this rate.
Topics: Amyotrophic Lateral Sclerosis; Humans; Mutation; Superoxide Dismutase
PubMed: 21047878
DOI: 10.1136/jnnp.2010.224501