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Cancer Reports (Hoboken, N.J.) Aug 2023Oxidative stress induced by free radical accumulation contributes to many pathologies, including cancer. Antioxidant defense system fails to scavenge free radicals when... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Oxidative stress induced by free radical accumulation contributes to many pathologies, including cancer. Antioxidant defense system fails to scavenge free radicals when it is excessively accumulated. Assessing individual antioxidant enzymes and total antioxidant capacity could direct the customized therapeutic strategies.
OBJECTIVE
Evaluation of total antioxidant status and enzyme glutathione peroxidase activity in the oral cancer group compared to the healthy control group.
METHOD
The literature search included databases PubMed, Science Direct, Wiley Online Library, Cochrane and Cross Reference between 1999 and 2021. The database search was completed in the month of August 2022. The extracted data were analyzed by Comprehensive Meta-Analysis (CMA) version 3 software (Biostat Inc. Englewood, NJ). Based on search strategies, 1435 articles have been retrieved from the database. In the segregated articles, 1365 were excluded due to duplicated articles, animal studies, low-quality studies, articles unrelated to the research question, and with unmatched objectives. Based on inclusion criteria, 70 articles were selected for full-text valuation. However, 33 articles were found highly suitable for inclusion and data extraction. Finally, 11 articles were selected for meta-analysis.
RESULTS
The meta-analysis of four included studies of tissue samples showed a significantly (p < .001) increased GPx activity in the oral cancer group, when compared to the control group, whereas three included studies of erythrocyte samples displayed a significantly (p < .001) decreased GPx activity in the oral cancer group than the control group with the pooled standardized mean difference value of -2.766 moles/min/g Hb at 95% CI (-3.297 to -2.234). The meta-analysis of the included studies depicted an insignificant (p = .947) reduction of salivary TAS levels in the oral cancer group when compared to the control group.
CONCLUSION
Our systematic review and meta-analysis depict antioxidant GPx enzyme activity in the regional tissue samples of the oral cancer group differs from other systemic biological fluid samples compared to the healthy control group.
Topics: Humans; Antioxidants; Glutathione Peroxidase; Mouth Neoplasms
PubMed: 37265029
DOI: 10.1002/cnr2.1842 -
International Journal of Molecular... Dec 2022Aim: The single-nucleotide polymorphism (SNP) rs713041, located in the regulatory region, is required to incorporate selenium into the selenoprotein glutathione... (Meta-Analysis)
Meta-Analysis Review
Aim: The single-nucleotide polymorphism (SNP) rs713041, located in the regulatory region, is required to incorporate selenium into the selenoprotein glutathione peroxidase 4 (GPX4) and has been found to have functional consequences. This systematic review aimed to conduct a meta-analysis to determine whether there is an association between GPX4 (rs713041) SNP and the risk of diseases in humans and its correlation with selenium status. Material and methods: A systematic search for English-language manuscripts published between January 1990 and November 2022 was carried out using six databases: CINAHL, Cochrane, Medline, PubMed, Scopus and Web of Science. Odds ratios (ORs) and 95% confidence intervals (CIs) were applied to assess a relationship between GPX4 (rs713041) SNP and the risk of different diseases based on three genetic models. Review Manager 5.4 and Comprehensive Meta-Analysis 4 software were used to perform the meta-analysis and carry out Egger’s test for publication bias. Results: Data from 21 articles were included in the systematic review. Diseases were clustered according to the physiological system affected to understand better the role of GPX4 (rs713041) SNP in developing different diseases. Carriers of the GPX4 (rs173041) T allele were associated with an increased risk of developing colorectal cancer in additive and dominant models (p = 0.02 and p = 0.004, respectively). In addition, carriers of the T allele were associated with an increased risk of developing stroke and hypertension in the additive, dominant and recessive models (p = 0.002, p = 0.004 and p = 0.01, respectively). On the other hand, the GPX4 (rs713041) T allele was associated with a decreased risk of developing pre-eclampsia in the additive, dominant and recessive models (p < 0.0001, p = 0.002 and p = 0.0005, respectively). Moreover, selenium levels presented lower mean values in cancer patients relative to control groups (SMD = −0.39 µg/L; 95% CI: −0.64, −0.14; p = 0.002, I2 = 85%). Conclusion: GPX4 (rs713041) T allele may influence colorectal cancer risk, stroke, hypertension and pre-eclampsia. In addition, low selenium levels may play a role in the increased risk of cancer.
Topics: Female; Humans; Pregnancy; Colorectal Neoplasms; Genetic Predisposition to Disease; Glutathione Peroxidase; Hypertension; Phospholipid Hydroperoxide Glutathione Peroxidase; Polymorphism, Single Nucleotide; Pre-Eclampsia; Selenium; Stroke
PubMed: 36555402
DOI: 10.3390/ijms232415762 -
Oxidative Medicine and Cellular... 2021Oral lichen planus (OLP) is a relatively common chronic inflammatory disease of unknown etiology, which might be caused by oxidative stress and impaired antioxidant... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Oral lichen planus (OLP) is a relatively common chronic inflammatory disease of unknown etiology, which might be caused by oxidative stress and impaired antioxidant defense.
OBJECTIVE
To systematically investigate the markers of oxidative stress and antioxidant systems in the saliva and blood from OLP patients and healthy controls.
METHODS
The PubMed, Cochrane Library, and Embase were systematically queried to collect data from studies in which oxidative stress/antioxidant markers from OLP and healthy subjects had been evaluated until March 10, 2021.
RESULTS
A total of 28 studies fulfilled inclusion criteria, and 25 of them, having 849 OLP patients and 1,052 control subjects and analyzing 12 oxidative stress and antioxidant state marker levels, were subjected to meta-analysis. We found a significant decrease in total antioxidant capacity (TAC) and uric acid (UA) and a significant increase in malondialdehyde (MDA) and nitric oxide (NO) levels in the saliva and serum/plasma of OLP patients. Moreover, a significant elevation of 8-hydroxy-deoxyguanosine (8-OHdG) and advanced oxidation protein product (AOOP) level and a decrease in vitamin C were also observed in the saliva of the OLP group. In contrast, salivary vitamin A, zinc, glutathione peroxidase (GPx), vitamin E, and nitrite were not significantly different between the two groups. In single studies, markers of oxidative stresses such as superoxide dismutase (SOD) and 8-isoprostanelevels were elevated in OLP, and antioxidant parameters such as glutathione (GSH) and total protein (TP) levels were dysregulated.
CONCLUSION
This meta-analysis helps to clarify the profile of oxidative stress and antioxidant state markers in OLP patients although existing evidence is rather heterogeneous and many studies are affected by several limitations. Larger and more standardized studies are warranted to ascertain whether these markers are potential causes or effects of OLP and whether antioxidant therapy improving oxidative stress will be useful.
Topics: Adult; Aged; Antioxidants; Biomarkers; Case-Control Studies; Female; Glutathione; Glutathione Peroxidase; Humans; Lichen Planus, Oral; Male; Malondialdehyde; Middle Aged; Nitric Oxide; Oxidative Stress; Saliva; Superoxide Dismutase; Uric Acid
PubMed: 34616506
DOI: 10.1155/2021/9914652 -
Antioxidants (Basel, Switzerland) Oct 2021Chronic obstructive pulmonary disease (COPD) is a progressive disease that is characterized by a state of persistent inflammation and oxidative stress. The presence of... (Review)
Review
Chronic obstructive pulmonary disease (COPD) is a progressive disease that is characterized by a state of persistent inflammation and oxidative stress. The presence of oxidative stress in COPD is the result of an imbalance between pro-oxidant and antioxidant mechanisms. The aim of this review was to investigate a possible association between glutathione peroxidase (GPx), a key component of antioxidant defense mechanisms, and COPD. A systematic search for relevant studies was conducted in the electronic databases PubMed, Web of Science, Scopus, and Google Scholar, from inception to June 2021. Standardized mean differences (SMDs) were used to express the differences in GPx concentrations between COPD patients and non-COPD subjects. Twenty-four studies were identified. In 15 studies assessing whole blood/erythrocytes (GPx isoform 1), the pooled results showed that GPx concentrations were significantly lower in patients with COPD (SMD = -1.91, 95% CI -2.55 to -1.28, < 0.001; moderate certainty of evidence). By contrast, in 10 studies assessing serum/plasma (GPx isoform 3), the pooled results showed that GPx concentrations were not significantly different between the two groups (very low certainty of evidence). The concentration of GPx-1, but not GPx-3, is significantly lower in COPD patients, suggesting an impairment of antioxidant defense mechanisms in this group.
PubMed: 34829616
DOI: 10.3390/antiox10111745 -
Medicine Dec 2023Hashimoto's thyroiditis (HT) is the prevailing form of autoimmune thyroiditis and the leading cause of hypothyroidism in iodine-sufficient regions worldwide. This study... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Hashimoto's thyroiditis (HT) is the prevailing form of autoimmune thyroiditis and the leading cause of hypothyroidism in iodine-sufficient regions worldwide. This study aims to evaluate the efficacy of vitamin D supplementation on HT through a meta-analysis of randomized controlled trials (RCTs).
METHODS
The databases searched included PubMed, and others. We included RCTs that the treatment group received vitamin D, while the control group received either a placebo or no treatment. The studies measured the baseline and endpoint levels of 25-hydroxyvitamin D [25(OH)D], thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), anti-thyroid peroxidase antibody (TPO-Ab), and thyroglobulin antibody (TG-Ab). We performed a meta-analysis to calculate the standardized mean difference (SMD) and 95% confidence interval (CI).
RESULTS
A total of 12 studies involving 862 individuals were included. Vitamin D supplementation has a significant impact on reducing the titers of TPO-Ab (SMD = -1.084, 95% CI = -1.624 to -0.545) and TG-Ab (SMD = -0.996, 95% CI = -1.579 to -0.413) in patients with HT, and it also improves thyroid function by decreasing TSH level (SMD = -0.167, 95% CI = -0.302 to 0.031) and increasing FT3 (SMD = 0.549, 95% CI = 0.077-1.020) and FT4 (SMD = 0.734, 95% CI = 0.184-1.285) levels. Active vitamin D (calcitriol) significantly reduces the titer of TPO-Ab compared to naive forms of vitamin D (vitamin D2 or D3); treatment durations > 12 weeks result in a more effective reduction of TPO-Ab levels and a more significant increase in FT4 and FT3 levels in patients with HT (meta-regression P < .05).
CONCLUSION
Vitamin D supplementation may have beneficial effects on HT patients by modulating immune responses and improving thyroid function.
Topics: Humans; Autoantibodies; Dietary Supplements; Hashimoto Disease; Thyrotropin; Vitamin D
PubMed: 38206745
DOI: 10.1097/MD.0000000000036759 -
Clinical Nutrition (Edinburgh, Scotland) Apr 2022Selenium is an antioxidant and anti-inflammatory nutrient and regulates important physiological processes, such as carbohydrate and lipid metabolism, immune system... (Meta-Analysis)
Meta-Analysis
BACKGROUND & AIMS
Selenium is an antioxidant and anti-inflammatory nutrient and regulates important physiological processes, such as carbohydrate and lipid metabolism, immune system actions, and adipocyte differentiation. Given these important functions, several studies have assessed the nutritional status of selenium to elucidate whether its homeostasis is impaired by excess adiposity, which in turn could contribute to the adipose tissue dysfunction and metabolic disorders. However, the results of these studies are quite controversial. Therefore, this systematic review and meta-analysis aimed to assess differences in the nutritional status of selenium in overweight/obese individuals.
METHODS
We searched the PubMed, Scopus, Web of Science, Embase, Cochrane Library, and Virtual Health Library databases. Studies comparing overweight or obese individuals with eutrophic individuals and assessing at least one marker of selenium were included. Comprehensive Meta-Analysis software was used to perform meta-analysis. The effect size was calculated using the raw mean difference or the standardized mean difference, with 95% confidence interval and a p-value of <0.05. Heterogeneity was determined using the I index. Subgroup analyses were performed according to sex, body mass index (BMI), and selenium content in the soil. The protocol of this review was registered in the Prospective Register of Systematic Reviews (registration number: CRD42020185405).
RESULTS
This systematic review included 73 articles, of which 65 articles were eligible for meta-analysis. There were no significant differences between the overweight/obesity and eutrophy groups in terms of dietary intake and plasma/serum levels of selenium and selenoprotein P levels. The activity of plasma/serum glutathione peroxidase was decreased in the overweight/obese children and adolescents; however, the difference was no statistically significant when the enzyme activity was analyzed in erythrocytes and whole blood. In the adult age group, overweight/obese individuals had decreased activity of both glutathione peroxidase isoforms compared to those individuals with eutrophy. In particular, the activity of erythrocyte glutathione peroxidase was significantly decreased in obese individuals and those living in regions with low-to-moderate selenium content in the soil. Regarding selenium excretion markers, overweight/obese individuals had lower levels of selenium in the urine and nails and a trend of higher levels of selenium in the hair than eutrophic individuals.
CONCLUSIONS
In conditions of excess adiposity, the main alteration in the nutritional status of selenium is a decrease in glutathione peroxidase activity, particularly in adults with obesity. In addition, reduced levels of selenium in urine and nails can be found in overweight or obese individuals.
Topics: Adolescent; Adult; Body Mass Index; Child; Humans; Nutritional Status; Overweight; Pediatric Obesity; Selenium
PubMed: 35276570
DOI: 10.1016/j.clnu.2022.02.007 -
Biological Trace Element Research Sep 2022Several studies have indicated that selenium deficiency may be detrimental in the context of various viral disorders, and in the case of COVID-19, several studies have...
Several studies have indicated that selenium deficiency may be detrimental in the context of various viral disorders, and in the case of COVID-19, several studies have reported heterogeneous results concerning the association of selenium deficiency with the severity of disease. To summarize the available data surrounding the association of body selenium levels with the outcomes of COVID-19, a systematic search was performed in the Medline database (PubMed), Scopus, Cochrane Library, Embase, and Web of Science using keywords including "SARS-CoV-2," "COVID-19," and "selenium," Studies evaluating the association of COVID-19 with body selenium levels were included. Among 1,862 articles viewed in the database search, 10 articles were included after title, abstract, and full-text review. One study was further included after searching the literature again for any newly published articles. Out of 11 included studies, 10 studies measured serum selenium level, and one study investigated urinary selenium level. Three of 10 studies measured serum SELENOP level as well as selenium level. Glutathione peroxidase-3 level in serum was also assessed in one study. The reported outcomes were severity, mortality, and risk of COVID-19. Nine studies indicated that a lower serum selenium level is associated with worse outcomes. Two studies reported no significant association between serum selenium level and COVID-19. In one study, urinary selenium level was reported to be higher in severe and fatal cases compared to non-severe and recovered patients, respectively. In most cases, selenium deficiency was associated with worse outcomes, and selenium levels in COVID-19 patients were lower than in healthy individuals. Thus, it could be concluded that cautious selenium supplementation in COVID-19 patients may be helpful to prevent disease progression. However, randomized clinical trials are needed to confirm this.
Topics: COVID-19; Humans; Malnutrition; SARS-CoV-2; Selenium; Selenoprotein P
PubMed: 34739678
DOI: 10.1007/s12011-021-02997-4 -
The International Journal of... Jun 2017People with schizophrenia and other psychosis show increased proinflammatory and prooxidative status. However, the few studies that have specifically assessed oxidative... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
People with schizophrenia and other psychosis show increased proinflammatory and prooxidative status. However, the few studies that have specifically assessed oxidative and inflammatory markers in early onset psychosis (onset before age 18) have shown contradictory results.
METHODS
Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines for systematic reviews and meta-analyses were used to conduct a systematic literature search to detect studies comparing inflammatory and oxidative markers in early onset psychosis patients and healthy controls.
RESULTS
Seven studies met criteria for the qualitative analysis. Four studies met criteria for meta-analysis, comprising an overall sample of 261 early onset psychosis patients and 246 healthy controls. Six independent meta-analyses were performed for catalase, glutathione, glutathione peroxidase, superoxide dismutase, total antioxidant status, and cell/DNA oxidative damage. No significant differences were found between early onset psychosis patients and controls in any of the parameters assessed. Heterogeneity among studies was high. Qualitative analysis of individual studies showed an association of inflammatory and oxidative markers with clinical, cognitive, and neurobiological outcomes, especially in longitudinal assessments.
CONCLUSIONS
Despite the lack of significant differences between early onset psychosis patients and controls in the oxidative markers assessed in the meta-analyses, results based on individual studies suggest that greater inflammation and oxidative stress might lead to poorer outcomes in patients with first episodes of early onset psychosis.
Topics: Acute Disease; Humans; Inflammation; Oxidative Stress; Psychotic Disorders; Schizophrenia
PubMed: 28575316
DOI: 10.1093/ijnp/pyx015 -
Medicine May 2023Evidence suggests that selenium supplementation could be useful in the treatment of Hashimoto thyroiditis (HT), but the available trials are heterogeneous. This study... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Evidence suggests that selenium supplementation could be useful in the treatment of Hashimoto thyroiditis (HT), but the available trials are heterogeneous. This study investigates clinically relevant effects of selenium supplementation in patients with HT.
METHODS
A systematic search was performed in PubMed, Web of Science, EMBASE, Scopus, and the Cochrane Library. The latest update was performed on December 3, 2022. We investigated the changes in thyroid peroxidase antibodies (TPOAb) and thyroglobulin antibodies (TgAb) after selenium supplementation. The effect sizes were expressed as weighted mean difference (WMD) with 95% confidence intervals (CIs).
RESULTS
After screening and full-text assessment, 7 controlled trials comprising 342 patients were included in the systematic review. The results showed that there was no significant change in TPOAb levels (WMD = -124.28 [95% CI: -631.08 to 382.52], P = .631, I2 = 94.5%) after 3 months of treatment. But there was a significant decrease in TPOAb levels (WMD = -284.00 [95% CI: -553.41 to -14.60], P < .05, I2 = 93.9%) and TgAb levels (WMD = -159.86 [95% CI: -293.48 to -26.24], P < .05, I2 = 85.3%) after 6 months of treatment.
CONCLUSIONS
Selenium supplementation reduces serum TPOAb and TgAb levels after 6 months of treatment in patients with HT, but future studies are warranted to evaluate health-related quality or disease progression.
Topics: Humans; Selenium; Dietary Supplements; Hashimoto Disease; Iodide Peroxidase; Thyroglobulin
PubMed: 37335715
DOI: 10.1097/MD.0000000000033791 -
Biomolecules Nov 2022Galectin-3 and myeloperoxidase (MPO) are novel biomarkers in the field of cardio-oncology, but conflicting results have been reported. Hence, a meta-analysis was... (Meta-Analysis)
Meta-Analysis Review
Galectin-3 and myeloperoxidase (MPO) are novel biomarkers in the field of cardio-oncology, but conflicting results have been reported. Hence, a meta-analysis was performed to assess the monitoring value of galectin-3 and MPO in cancer-therapy-related cardiotoxicity. PubMed, Cochrane, Web of Science, Embase, CNKI databases and ClinicalTrials.gov were queried. According to the predefined inclusion and exclusion criteria, eight studies with 1979 patients were included in this meta-analysis. The examination of the study's heterogeneity (I), quality assessment and statistical analysis were performed by two reviewers. No significant differences in galectin-3 levels were noted before and after treatment (WMD = -0.10, 90% CI -6.06-5.85, I: 99%), and a weaker relationship was observed between galectin-3 evaluations and cancer-therapy-related cardiotoxicity (HR = 1.39, 90% CI 0.97-1.98, I: 0%). However, MPO levels were increased in patients post-treatment (SMD = 0.58, 90% CI 0.35-0.80, I: 56%), and an increased risk of cardiotoxicity was associated with early pre-post MPO assessments (HR = 1.16, 90% CI 1.02-1.32, I: 21%). Surprisingly, the MPO levels were a more effective indicator of the response to tumor treatment compared with the TnI (SMD = 2.46, 90% CI -0.26-5.19, I: 96%) and NT-proBNP levels (SMD = 1.08, 90% CI -0.82-2.98, I: 96%). In conclusion, our meta-analysis suggests that MPO may rep-resent a potential biomarker for the early detection of cardiotoxicity in current cardio-oncology practice, but the monitoring value of galectin-3 requires further study.
Topics: Humans; Biomarkers; Cardiotoxicity; Galectin 3; Neoplasms; Peroxidase; Antineoplastic Agents
PubMed: 36551214
DOI: 10.3390/biom12121788