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1.
Effect of omega-3 fatty acids supplementation on cardio-metabolic and oxidative stress parameters in patients with chronic kidney disease: a systematic review and meta-analysis.
Fazelian, S, Moradi, F, Agah, S, Hoseini, A, Heydari, H, Morvaridzadeh, M, Omidi, A, Pizarro, AB, Ghafouri, A, Heshmati, J
BMC nephrology. 2021;(1):160
Abstract
BACKGROUND Omega-3 fatty acids (FAs) have been suggested as a beneficial supplement in chronic kidney disease (CKD) patients, but the results of randomized clinical trials (RCTs) are controversial. We conducted a systematic review and meta-analysis to evaluate all the RCTs about the impact of omega-3 FAs supplementation on cardiometabolic outcomes and oxidative stress parameters in patients with CKD. METHODS We performed a systematic database search in PubMed/MEDLINE, EMBASE, Scopus, Web of Science, and Cochrane Central, up to May 2020. We included all placebo-controlled randomized trials that assessed the effect of omega-3 FAs supplementation on any cardiometabolic outcomes: blood pressure, total cholesterol (TC), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) or triglycerides (TG) and oxidative stress parameters. Data were pooled using DerSimonian-Laird's random-effects model. RESULTS Finally, thirteen articles met the inclusion criteria for this review omega-3 FAs supplementation significantly decrease TC (SMD: -0.26; 95% CI: - 0.51, - 0.02; I2 = 52.7%), TG (SMD: -0.22; 95% CI: - 0.43, - 0.02; I2 = 36.0%) and Malondialdehyde (MDA) levels (SMD: -0.91; 95% CI: - 1.29, - 0.54; I2 = 00.0%) and also significantly increase superoxide dismutase (SOD) (SMD: 0.58; 95% CI: 0.27, 0.90; I2 = 00.0%) and Glutathione peroxidase (GPx) (SMD: 0.50; 95% CI: 0.14, 0.86; I2 = 00.0%) activities. However our results show that omega-3 FAs supplementation have no significant effects on HDL, LDL and blood pressure. Conclusion This systematic review and meta-analysis supports current evidence for the clinical benefit of omega-3 FAs intake to improve cardiometabolic parameters in CKD patients. However, well-designed RCTs still needed to provide a conclusive picture in this field.
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2.
Effects of grape products on inflammation and oxidative stress: A systematic review and meta-analysis of randomized controlled trials.
Ghalishourani, SS, Farzollahpour, F, Shirinbakhshmasoleh, M, Kolahdouz, S, Ghaedi, E, Behrouzian, M, Haghighian, HK, Campbell, MS, Asbaghi, O, Moodi, V
Phytotherapy research : PTR. 2021;(9):4898-4912
Abstract
This systematic review and meta-analysis of randomized controlled trials (RCTs) were conducted to determine the effects of grapes and grape products on inflammation and oxidative stress among adults. PubMed, Scopus, ISI Web of Science, and Cochrane Library databases were searched up to July 2020 to identify RCTs investigating the effects of grape and grape products on inflammatory and oxidative stress markers. Weighted mean differences (WMD) were pooled using a random-effects model. Of the 8,962 identified studies, 24 RCTs (27 arms) were included in the statistical analysis. Grape products significantly reduced serum C-reactive protein (CRP) levels (WMD: -0.35 mg/L; 95% CI: -0.62, -0.09, p = .008), but they had no significant effect on serum tumor necrosis factor-alpha (TNF-α) (WMD = -1.08 pg/ml; 95% CI: -2.29, 0.11, p = .07), interleukin-6 (IL-6) (WMD = 0.13 pg/ml; 95% CI: -0.35, 0.60, p = .60), total antioxidant capacity (TAC) (WMD = 0.15; 95% CI: -0.35, 0.65, p = .54), or malondialdehyde (MDA) (WMD = 0.14; 95% CI: -0.64, 0.92, p = .72). The analysis indicated possible decreasing effects of grapes and grape products on CRP, but they might not be able to change IL-6, TNF-α, TAC, and MDA concentrations. Nonetheless, further studies are warranted before definitive conclusions may be reached.
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3.
Beneficial Effects of Vitamin E Supplementation on Endothelial Dysfunction, Inflammation, and Oxidative Stress Biomarkers in Patients Receiving Hemodialysis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
Nguyen, TTU, Yeom, JH, Kim, W
International journal of molecular sciences. 2021;(21)
Abstract
Inflammation and oxidative stress are closely related to cardiovascular complications and atherosclerosis, and have the potential to lead to an increase in death in patients receiving hemodialysis. Vitamin E has antioxidant and anti-inflammatory properties. We conducted a systematic review and meta-analysis to assess the effects of vitamin E supplementation on endothelial dysfunction, inflammation, and oxidative stress biomarkers in adult patients receiving hemodialysis. We searched the MEDLINE, EMBASE, Web of Science, and Cochrane Library databases and identified randomized controlled trials of adult patients receiving hemodialysis until 30 August 2021. A total of 11 trials with 491 randomized patients were included. The pooled data indicated that vitamin E supplementation significantly decreased intercellular adhesion molecule-1 [standardized mean difference (SMD): -1.35; 95% confidence interval (CI): -2.57, -0.13; p = 0.03, I2 = 89%], vascular cell adhesion molecule-1 (SMD: -1.08; 95% CI: -2.05, -0.11; p = 0.03, I2 = 81%), C-reactive protein (SMD: -0.41; 95% CI: -0.75, -0.07; p = 0.02, I2 = 64%), and malondialdehyde (SMD: -0.76; 95% CI: -1.26, -0.25; p = 0.003, I2 = 77%) levels, but not interleukin-6 levels compared to those in the control group. Our results suggest that vitamin E supplementation may help alleviate oxidative stress and both vascular and systemic inflammation in patients receiving hemodialysis.
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4.
The effect of Nigella sativa on oxidative stress and inflammatory biomarkers: a systematic review and meta-analysis.
Malekian, S, Ghassab-Abdollahi, N, Mirghafourvand, M, Farshbaf-Khalili, A
Journal of complementary & integrative medicine. 2021;(2):235-259
Abstract
OBJECTIVES The present systematic review of literature was conducted to study the effect of Nigella sativa (N.S) on oxidative stress and inflammatory biomarkers. CONTENT Different online databases such as Cochrane Central Register of Controlled Trials, MEDLINE (PubMed), Scopus, Web of Sciences, EMBASE, and Clininaltrial.gov for English articles and national databases of SID, Magiran, Irandoc, and Iranmedex for Persian articles, which were published until March; 2019 were scrutinized. All Randomised Controlled Trials (RCTs) and quasi-experimental studies that aimed to compare the impact of N.S along, with placebo or without supplementation, on inflammatory factors and oxidative stress were entered in the present study. SUMMARY Finally, 11 RCTs covering 710 women and men, in total, were participated in the present meta-analysis. Significant differences were observed in Tumor Necrosis Factor alpha (TNF-α) (Weighted Mean Difference (WMD) =-2.15 pg/mL, 95% Confidence Interval (CI) =-3.22--1.09, I2=32%; 5 trials with 262 participants) superoxide dismutase (WMD=63.79 µ/gHb, 95% CI=6.84-120.75, I2=0%; 2 trials, with 88 participants), and total antioxidant capacity (WMD=0.34 mmol/L, 95% CI=0.04 to 0.63, I2=94%; 5 trials with 232 participants). Nevertheless, there was no significant difference in high sensitivity C-reactive protein (WMD=-0.98 mg/L, 95% CI=-1.98-0.03, I2=78%; 5 trials with 267 participants), Interleukin 6 (IL-6) (WMD=-0.25 pg/mL, 95% CI=-0.65 to 0.16, I2=0%; 2 trials with 134 participants), and malondialdehyde (WMD=-0.95 nmol/mL, 95% CI=-1.97-0.08, I2=68%; 4 trials with 179 participants). OUTLOOK Generally speaking, N.S probably results in the improvement of superoxide dismutase serum levels, TNF-α, and total antioxidant capacity. Thus, further studies are required to fully assess its impacts on all oxidative stress and inflammatory biomarkers.
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5.
The effects of vitamin E supplementation on malondialdehyde as a biomarker of oxidative stress in haemodialysis patients: a systematic review and meta-analysis.
Bergin, P, Leggett, A, Cardwell, CR, Woodside, JV, Thakkinstian, A, Maxwell, AP, McKay, GJ
BMC nephrology. 2021;(1):126
Abstract
BACKGROUND Haemodialysis (HD) patients tend to have higher levels of oxidative stress (OS), associated with increased morbidity and premature mortality, compared to the general population. Levels of malondialdehyde (MDA), a biomarker of OS, are reduced by the antioxidant properties of vitamin E (VE) but outcomes from randomised control trials of VE supplementation on MDA in HD patients have been inconsistent. METHODS We undertook a systematic review and meta-analysis of adult HD patients from VE supplementation studies with measures of MDA. The following search criteria of MEDLINE and EMBASE were considered from inception to January 2020: 'dialysis' AND 'Vitamin E OR tocopherol' AND 'malondialdehyde OR MDA'. Two reviewers independently extracted study data and assessed risk of bias. Mean MDA levels and standard deviation were determined before and after VE supplementation. Standardised mean difference (SMD) and standard error were calculated as the within person difference and units of measure were not consistently recorded across all studies. The SMD were pooled using random effects meta-analysis. RESULTS The SMD of MDA levels from 18 comparisons was significantly lower in HD patients following VE supplementation (- 1.55; confidence interval: - 2.17 to - 0.94, P < 0.00001). There were significant levels of heterogeneity between studies (I2 value = 91%; P < 0.00001) with evidence of potential publication bias toward smaller studies. CONCLUSIONS Our findings support the use of VE to reduce the effects of OS in HD patients although high levels of heterogeneity and variation in the methodological approaches used by some studies highlight the need for further investigation.
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6.
Clinical effectiveness of zinc supplementation on the biomarkers of oxidative stress: A systematic review and meta-analysis of randomized controlled trials.
Mousavi, SM, Hajishafiee, M, Clark, CCT, Borges do Nascimento, IJ, Milajerdi, A, Amini, MR, Esmaillzadeh, A
Pharmacological research. 2020;:105166
Abstract
BACKGROUND Oxidative stress plays an important role in the occurrence of chronic diseases. Zinc supplementation is also known to be an antioxidant agent. While, there is no review on the effects of zinc supplementation on oxidative stress, this study aimed to systematically summarize randomized clinical trials (RCTs) which have evaluated the impacts of zinc supplementation on oxidative stress biomarkers. METHODS Systematic searches were performed using the PubMed/Medline, Scopus, and Google Scholar databases, up to April 2020. All RCTs assessed the effect of oral zinc supplementation on serum malondialdehyde (MDA), total antioxidant capacity (TAC), glutathione (GSH), and nitric oxide (NO) levels, were included. For each variable, mean differences (MD) and standard deviations (SDs) were combined using the random-effects model, and the fractional polynomial model was used to implement the dose-response analysis. RESULTS Ten RCTs were included. The pooled analysis of data showed that zinc supplementation significantly reduced MDA levels (MD: -0.42 μmol/L; 95 % CI: -0.71 to -0.13), increased serum TAC (MD: 225.96 mmol/L; 95 % CI: 68.42-383.5) and GSH levels (MD: 49.99 μmol/L; 95 % CI: 2.25 t 97.73), compared with the placebo group. In contrast, no significant changes were seen in NO levels following zinc supplementation (MD: -1.66 μmol/L; 95 % CI: -5.89 to 2.57). Dose-response analysis showed a significant non-linear relationship between zinc supplementation dosage and serum levels of MDA (p < 0.01), but not other biomarkers. CONCLUSIONS The current study showed that zinc supplementation would significantly decrease MDA and increase TAC and GSH, but not NO levels. Thus, it encourages the use of zinc supplementation in oxidative stress-related diseases.
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7.
Effect of Nigella sativa L. supplementation on inflammatory and oxidative stress indicators: A systematic review and meta-analysis of controlled clinical trials.
Mohit, M, Farrokhzad, A, Faraji, SN, Heidarzadeh-Esfahani, N, Kafeshani, M
Complementary therapies in medicine. 2020;:102535
Abstract
AIMS: The objective of the present study was to perform a systematic review and meta-analysis on randomized controlled trials (RCTs) assessing the effects of Nigella sativa L. supplementation on the circulating inflammatory and oxidative stress markers, including C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), total antioxidant capacity (TAC) and malondialdehyde (MDA). METHODS Systematic search was performed up to March 2020 using PubMed, Scopus, and ISI web of science databases. Two reviewers independently assessed study eligibility, extracted data, and evaluated methodological quality of included primary studies. Statistical heterogeneity was assessed using I-square (I2) statistic. Data were pooled by using the random-effect model and standardized mean difference (SMD) was considered as the summary effect size. RESULTS Twelve trials were identified to be suitable for our meta-analysis. The pooled results using random effects model indicated that Nigella sativa supplementation significantly reduced CRP (SMD: -0.35; 95% CI: -0.59, -0.12, P < 0.001, I2 = 10.5%) and MDA concentrations (SMD: -0.56; 95% CI: -0.98, -0.15, P < 0.001, I2 = 64.7%). Moreover, Nigella sativa supplementation increased TAC (SMD: 0.48; 95% CI: 0.09, 0.87, P = 0.01, I2 = 65.6%) levels; however, it did not affect TNF-α (SMD: -0.35; 95% CI: -0.70, 0.01, P = 0.05, I2 = 58.2%). CONCLUSION Nigella sativa supplementation is associated with improved inflammation and oxidative status. Additional prospective studies are recommended using higher supplementation doses and longer intervention period.
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8.
The Effects of Supplementation with Probiotic on Biomarkers of Oxidative Stress in Adult Subjects: a Systematic Review and Meta-analysis of Randomized Trials.
Zamani, B, Sheikhi, A, Namazi, N, Larijani, B, Azadbakht, L
Probiotics and antimicrobial proteins. 2020;(1):102-111
Abstract
Previous studies have supposed that probiotic supplementation led to a positive effect on different health outcomes. Furthermore, several studies indicated that probiotics supplementation improved antioxidant status, while some studies did not indicate these effects. Hence, current systematic review and meta-analysis study was conducted to determine the effect of probiotic supplementation on some oxidative stress biomarkers among adult subjects. We searched four electronic databases PubMed, SCOPUS, ISI Web of Science, and the Cochrane Library till November 2017. Clinical trials that compared the effects of probiotic supplementation with the control group were included. A random-effect model was used to pool weighted mean difference (WMD). Finding of 11 included studies (n = 577) indicated that probiotic supplementation increased total antioxidant capacity (TAC) (WMD 77.30 mmol/L; 95% confidence interval [CI] 2.60, 152.01; I2 = 88.3%) and reduced malondialdehyde (MDA) (WMD - 0.31 μmol/L; 95% CI - 0.54, - 0.08; I2 = 71.5%) significantly compared to the control group. However, its effects on glutathione (GSH) was not significant (WMD = 19.32 μmol/L; 95% CI - 18.70, 57.33; I2 = 64.9%). The current meta-analysis revealed that probiotic supplementation may result in increasing TAC and lowering MDA, which improve antioxidant status. However, due to high heterogeneity, findings should be interpreted with caution. Further investigations are required to elucidate the effect of supplementation with probiotics on biomarkers of antioxidants.
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9.
Effect of omega-3 fatty acid plus vitamin E Co-Supplementation on oxidative stress parameters: A systematic review and meta-analysis.
Sepidarkish, M, Akbari-Fakhrabadi, M, Daneshzad, E, Yavari, M, Rezaeinejad, M, Morvaridzadeh, M, Heshmati, J
Clinical nutrition (Edinburgh, Scotland). 2020;(4):1019-1025
Abstract
BACKGROUND & AIMS The impact of combined omega-3 FAs and vitamin E supplementation on oxidative stress (OS) has been evaluated in several studies. However the results are inconsistent. Therefore, we performed a systematic review and meta-analysis to assess the role of omega-3 FAplus vitamin E on anti-oxidant and OS parameters. METHODS We searched five databases (PubMed, Embase, Web of Sciences, Scopus and the Cochrane Central Register of Controlled Trials) from inception until March 15th 2018 for RCT covering OS parameters combined with omega-3 FAs and vitamin E. The effect of omega-3 FAs plus vitamin E combination on OS factors was determined as the standardized mean difference (SMD) calculated according to DerSimonian and Laird for the random effects model. RESULTS Nine articles were included in our analyses, significant improvements were observed in trials supplementing with omega-3 FAs plus vitamin E vs placebo for total antioxidant capacity (TAC) (SMD=0.63, 95%CI: 0.31 to 0.95, P<0.001) and nitric oxide (NO) (SMD=0.55, 95%CI: 0.23 to 0.87, P<0.001). Significant reduction was observed for malondialdehyde (MDA) (SMD: -0.48, 95%CI: -0.68 to -0.28, P<0.001). However, the results of meta-analysis did not show a significant difference in levels of glutathione (GSH) (SMD=0.34, 95%CI: -0.07 to 0.75, P=0.10), superoxide dismutase (SOD) activity (SMD: 0.07, 95% CI: -0.58 to 0.73, P=0.82) and Catalase (CAT) activity (SMD: 0.74, 95% CI: -0.30 to 1.79, P=0.16). CONCLUSION Co-supplementation with omega-3 FAs and vitamin E increases the levels of NO and TAC, while MDA levels decrease compared to placebo. However, the results showed no significant alterations on GSH concentrations, CAT, and SOD activities.
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10.
Oxidative stress markers in preeclamptic placentas: A systematic review with meta-analysis.
Ferreira, RC, Fragoso, MBT, Bueno, NB, Goulart, MOF, de Oliveira, ACM
Placenta. 2020;:89-100
Abstract
INTRODUCTION Oxidative stress (OS) is the basis of several diseases. Preeclampsia (PE) is a multisystemic syndrome, considered one of the major causes of maternal and fetal mortality. The placenta is considered the main anatomical pathogenetic substrate for the disease, being the placental OS a likely critical pathway in the pathogenesis of PE. This meta-analysis aimed to verify whether there is OS in the preeclamptic placenta and which markers are altered in this condition. METHODS The search was conducted in the following databases: MEDLINE (via PubMed), Lilacs and Scopus. Relevant studies were identified until May 2020. The quality of the studies was evaluated according to the Newcastle-Ottawa scale. RESULTS From the 3998 screened records, 43 were finally included in the systematic review, and 23 in the meta-analysis. The biomarkers evaluated were related to cell and macromolecules' damage, such as malondialdehyde (MDA), 8-hydroxy-2'-deoxyguanosine (8-OH-dG), lipid peroxides, isoprostane, total oxidant status (TOS), carbonylated proteins and some of the reactive oxygen and nitrogen species (RONS), like hydrogen peroxide and nitric oxide. It was also related to antioxidant activity, both enzymatic, including superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), glutathione S-transferase and total antioxidant status, and non-enzymatic, through quantification of reduced glutathione, vitamin C and E, zinc and copper. CONCLUSION It was observed that there was OS in the preeclamptic placentas, based on results, like lower activity of some of the enzymes of the antioxidant system (SOD and GPx) as well as the increase in oxidative damage markers (MDA and lipid peroxide), corroborating literature data.