scholarly journals Effect of Green Tea Supplementation on Antioxidant Status in Adults: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Antioxidants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1731
Author(s):  
Niloufar Rasaei ◽  
Omid Asbaghi ◽  
Mahsa Samadi ◽  
Leila Setayesh ◽  
Reza Bagheri ◽  
...  

It is well-established that green tea supplementation has antioxidant properties. However, whether green tea supplementation leads to oxidative stress reduction remains unclear, as clinical investigations on this subject have yielded inconsistent outcomes. Consequently, we aimed to determine the effects of green tea supplementation on oxidative stress in adults. A systematic search of English language publications up to 21 August 2021 was carried out in PubMed, Scopus, Embase, and ISI Web of Science, utilizing pertinent keywords. These searches included randomized controlled trials (RCTs) evaluating the relationship between green tea supplementation, malondialdehyde (MDA), and total antioxidant capacity (TAC) in adults. A random-effects model was used to estimate the weighted mean difference (WMD) and 95% confidence intervals (95% CI). Meta-regression and non-linear dose-response analyses were performed to investigate the association between the dosage of green tea (mg/day) and the duration of the intervention (weeks) with pooled effect size. Sixteen RCTs with seventeen arms including 760 participants met the inclusion criteria. Our results indicated that green tea supplementation had significant effects on TAC (weighted mean difference [WMD]: 0.20 mmol/L; 95% CI: 0.09, 0.30, p < 0.001) and significant heterogeneity between studies (I2 = 98.6%, p < 0.001), which was largely related to gender and body mass index (BMI). Subgroup analysis in TAC identified a significant relationship except with low dose supplementation and obese individuals. No relationship between MDA and green tea supplementation was observed in any subgroups; however, meta-regression analysis revealed a linear inverse association between the dosage and significant change in MDA (r = −2117.18, p = 0.017). Our outcomes suggest that green tea supplementation improves TAC and affects MDA based on the dose of the intervention in adults. Future RCTs with longer durations are needed to expand our findings.

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Sahar Sarkhosh-Khorasani ◽  
Zohreh Sadat Sangsefidi ◽  
Mahdieh Hosseinzadeh

Abstract Background The literature showed that Grape Products Containing Polyphenols (GPCP) had anti-oxidant activity. However, the effects of GPCP on different biomarkers of oxidative stress are still controversial. In this regard, this systematic review and meta-analysis aimed to evaluate the effect of Grape Products Containing Polyphenols (GPCP) intake on oxidative stress markers. Methods PubMed, Scopus, Web of Science, and Google Scholar data bases were searched up to August 20, 2020. A random-effects model, weighted mean difference (WMD), and 95% confidence interval (CI) were applied for data analysis. Meta-analysis was conducted over 17 eligible RCTs with a total of 633 participants. The study registration number is CRD42019116696. Results A significant increase was observed in Total Antioxidant Capacity (TAC) (weighted mean difference (WMD) = 1.524 mmol/L, 95% confidence interval (CI): 0.83, 2.21). Intake of GPCP enhanced Superoxide Dismutase (SOD) (WMD = 0.450 mmol/L, 95% CI: 0.23, 0.66), TAC (WMD = 2.829 mmol/L, 95% CI: 0.13, 5.52), and Oxygen Radical Absorbance Capacity (ORAC) (WMD = 0.524 μmol/L, 95% CI: 0.42, 0.62) among healthy participants. Higher GPCP doses increased SOD (WMD = 0.539 U/mgHb, 95% CI: 0.24, 0.82) and ORAC (WMD = 0.377 μmol/L, 95% CI: 0.08, 0.67), whereas longer intervention periods enhanced ORAC (WMD = 0.543 μmol/L, 95% CI: 0.43, 0.64). Conclusion GPCP intake may partly improve status of oxidative stress, but further well-designed trials are required to confirm these results.


2013 ◽  
Vol 119 (1) ◽  
pp. 178-190 ◽  
Author(s):  
Gildasio S. De Oliveira ◽  
Lucas J. Castro-Alves ◽  
Jamil H. Khan ◽  
Robert J. McCarthy

Abstract Background: Systemic magnesium has been used to minimize postoperative pain with conflicting results by clinical studies. It remains unknown whether the administration of perioperative systemic magnesium can minimize postoperative pain. The objective of the current investigation was to evaluate the effect of systemic magnesium on postoperative pain outcomes. Methods: A wide search was performed to identify randomized controlled trials that evaluated the effects of systemic magnesium on postoperative pain outcomes in surgical procedures performed under general anesthesia. Meta-analysis was performed using a random-effect model. Publication bias was evaluated by examining the presence of asymmetric funnel plots using Egger regression. Results: Twenty randomized clinical trials with 1,257 subjects were included. The weighted mean difference (99% CI) of the combined effects favored magnesium over control for pain at rest (≤4 h, −0.74 [−1.08 to −0.48]; 24 h, −0.36 [−0.63 to −0.09]) and with movement at 24 h, −0.73 (−1.37 to −0.1). Opioid consumption was largely decreased in the systemic magnesium group compared with control, weighted mean difference (99% CI) of −10.52 (−13.50 to −7.54) mg morphine IV equivalents. Publication bias was not present in any of the analysis. Significant heterogeneity was present in some analysis, but it could be partially explained by the sole intraoperative administration of magnesium compared with the intraoperative and postoperative administration. None of the studies reported clinical toxicity related to toxic serum levels of magnesium. Conclusion: Systemic administration of perioperative magnesium reduces postoperative pain and opioid consumption. Magnesium administration should be considered as a strategy to mitigate postoperative pain in surgical patients.


2020 ◽  
Vol 15 (1) ◽  
pp. 37-42 ◽  
Author(s):  
Xiaobin Yang ◽  
Haishi Zheng ◽  
Yuan Liu ◽  
Dingjun Hao ◽  
Baorong He ◽  
...  

Aims/Background: Ovariectomy (OVX)-induced murine model is widely used for postmenopausal osteoporosis study. Our current study was conducted to systematically review and essentially quantified the bone mass enhancing effect of puerarin on treating OVX-induced postmenopausal osteoporosis in murine model. Methods: Literatures from PUBMED, EMBASE, and CNKI were involved in our searching strategy by limited the inception date to January 9th, 2019. Moreover, the enhancing effect of puerarin on bone mass compared to OVX-induced rats is evaluated by four independent reviewers. Finally, all the data were extracted, quantified and analyzed via RevMan, besides that in our current review study, we assessed the methodological quality for each involved study. Results: Based on the searching strategy, eight randomization studies were finally included in current meta-analysis and systematic review. According to the data analysis by RevMan, puerarin could improve bone mineral density (BMD); (eight studies, n=203; weighted mean difference, 0.05; 95% CI, 0.03-0.07; P<0.0001) using a random-effects model. There is no significant difference between puerarin and estrogen (seven studies, n=184; weighted mean difference, 0.00; 95% CI, -0.01 to 0.00; P=0.30). Conclusions: Puerarin showed upregulating effects on bone mass in OVX-induced postmenopausal osteoporosis in murine model. More studies of the effect of puerarin on bone density in OVX animals are needed.


Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1076
Author(s):  
Guoyi Tang ◽  
Yu Xu ◽  
Cheng Zhang ◽  
Ning Wang ◽  
Huabin Li ◽  
...  

Nonalcoholic fatty liver diseases (NAFLD) represent a set of liver disorders progressing from steatosis to steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma, which induce huge burden to human health. Many pathophysiological factors are considered to influence NAFLD in a parallel pattern, involving insulin resistance, oxidative stress, lipotoxicity, mitochondrial dysfunction, endoplasmic reticulum stress, inflammatory cascades, fibrogenic reaction, etc. However, the underlying mechanisms, including those that induce NAFLD development, have not been fully understood. Specifically, oxidative stress, mainly mediated by excessive accumulation of reactive oxygen species, has participated in the multiple NAFLD-related signaling by serving as an accelerator. Ameliorating oxidative stress and maintaining redox homeostasis may be a promising approach for the management of NAFLD. Green tea is one of the most important dietary resources of natural antioxidants, above which epigallocatechin gallate (EGCG) notably contributes to its antioxidative action. Accumulative evidence from randomized clinical trials, systematic reviews, and meta-analysis has revealed the beneficial functions of green tea and EGCG in preventing and managing NAFLD, with acceptable safety in the patients. Abundant animal and cellular studies have demonstrated that green tea and EGCG may protect against NAFLD initiation and development by alleviating oxidative stress and the related metabolism dysfunction, inflammation, fibrosis, and tumorigenesis. The targeted signaling pathways may include, but are not limited to, NRF2, AMPK, SIRT1, NF-κB, TLR4/MYD88, TGF-β/SMAD, and PI3K/Akt/FoxO1, etc. In this review, we thoroughly discuss the oxidative stress-related mechanisms involved in NAFLD development, as well as summarize the protective effects and underlying mechanisms of green tea and EGCG against NAFLD.


2021 ◽  
Vol 12 ◽  
Author(s):  
Dong Wang ◽  
Zhen Ruan ◽  
Rongchao Zhang ◽  
Xuejing Wang ◽  
Ruihui Wang ◽  
...  

Background: Earthworm, also called dilong (Chinese language), has been used as a traditional Chinese medicine for thousands of years. Recently, some scientists believe that earthworm extracts (EE) can promote wound healing. However, its effectiveness remains controversial. We conducted a meta-analysis to evaluate the effect of EE on wound healing based on the healing rate.Methods: We comprehensively reviewed literature that mentioned EE for wound healing in the PubMed, Cochrane Library, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), VIP database for Chinese Technical Periodicals, and WanFang database that have been published until January 2021. We computed weighted mean difference (WMD) for analysis with RevMan 5.3 software in animal and human models groups. Two researchers independently selected studies and evaluated the risk of bias with the Cochrane Collaboration tool. The quality of the evidence was assessed with the Cochrane risk of bias tool. This study is registered on PROSPERO (CRD42020168400).Results: From 2,486 articles, we selected 16 studies for analysis. EE treatment was associated with improvements in wound healing performance based on wound healing rate (mouse model: weighted mean difference (WMD) = 3.55, 95% confidence interval (CI): 2.34–4.77, p &lt; 0.00001; rat model: WMD = 17.29, 95% CI: 5.75–28.82, p = 0.003; rabbit model: WMD = 19.29, 95% CI: 9.95–28.64, p &lt; 0.0001). Clinical studies also confirmed that EE could reduce healing time in hospital (WMD = −8.94, 95% CI: −17.75 to −0.14, p = 0.05).Conclusion: The results of this meta-analysis demonstrated the efficacy of EE on wound healing process. As a corollary, EE can be a useful natural product for wound healing drug development.Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=168400, identifier CRD42020168400.


2008 ◽  
Vol 23 (6) ◽  
pp. 520-530 ◽  
Author(s):  
Suzana Angélica Silva Lustosa ◽  
Humberto Saconato ◽  
Álvaro Nagib Atallah ◽  
Gaspar de Jesus Lopes Filho ◽  
Delcio Matos

PURPOSE: To compare morbidity, mortality, recurrence and 5-year survival between D1 and D2 or D3 for treatment of gastric cancer. METHODS: Systematic review and meta-analysis of RCTs. Metaview in RevMan 4.2.8 for analysis; statistical heterogeneity by Cochran's Q test (P<0.1) and I² test (P>50%). Estimates of effect were calculated using random effects model. RESULTS: D2 or D3 was associated with higher in-hospital mortality, with RR = 2.13, p=0.0004, 95% CI, 1.40 to 3.25, I²=0%, P=0.63; overall morbidity showed higher incidence in D2 or D3, RR = 1.98, p<0.00001, 95% CI, 1.64 to 2.38, I² = 33.9%, P=0.20; operating time showed longer duration in D2 or D3, weighted mean difference of 1.05, p<0.00001, 95% CI, 0.71 to 1.38, I² = 78.7%, P=0.03, with significant statistical heterogeneity; reoperation showed higher rate in D2 or D3, with RR = 2.33, p<0.0001, 95% CI, 1.58 to 3.44, I² = 0%, P=0.99; hospital stay showed longer duration in the D2 or D3, with weighted mean difference of 4.72, p<0.00001, 95% CI, 3.80 to 5.65, I² = 89.9%, P<0.00001; recurrence was analyzed showed lower rate in D2 or D3, with RR = 0.89, p=0.02, 95% CI, 0.80 to 0.98, I² = 71.0%, P = 0.03, with significant statistical heterogeneity; mortality with recurrent disease showed higher incidence in D1, with RR = 0.88, p=0.04, 95% CI, 0.78 to 0.99, I² =51.8%, P=0.10; 5-year survival showed no significant difference, with RR = 1.05, p=0.40, 95% CI, 0.93 to 1.19, I² = 49.1% and P=0.12. CONCLUSIONS: D2 or D3 lymphadenectomy procedure is followed by higher overall morbidity and higher in-hospital mortality; D2 or D3 lymphadenectomy shows lower incidence of recurrence and lower mortality with recurrent disease, when analysed altogether with statistical heterogeneity; D2 or D3 lymphadenectomy has no significant impact on 5-year survival.


2021 ◽  
Vol 8 ◽  
Author(s):  
Tianyi Zhang ◽  
Chengyang Xu ◽  
Rui Zhao ◽  
Zhipeng Cao

Biomarkers such as B-type natriuretic peptide (BNP), N-terminal pro-BNP (NT-proBNP), cardiac troponin (cTn), and CK-MB contribute significantly to the diagnosis of cardiovascular disease (CVD). Recent studies have demonstrated that suppression of tumorigenicity 2 (ST2) is associated with CVD, but a meta-analysis of ST2 levels in different CVDs has yet to be conducted. Therefore, the present study aimed to investigate soluble ST2 (sST2) levels in patients with ischemic heart disease (IHD), myocardial infarction (MI), and heart failure (HF). A total of 1,425 studies were searched across four databases, of which 16 studies were included in the meta-analysis. The Newcastle–Ottawa Quality Assessment Scale (NOS) values of all 16 studies were ≥7. The meta-analysis results indicated that the sST2 level was not correlated with IHD (standard mean difference [SMD] = 0.58, 95% confidence interval [95% CI] = 0.00 to 1.16, p = 0.05) or MI (weighted mean difference [WMD] = 0.17, 95% CI = −0.22 to 0.55, p = 0.40) but was significantly associated with HF (WMD = 0.21, 95% CI = 0.04 to 0.38, p = 0.02; I2 = 99%, p &lt; 0.00001). sST2 levels did not differ significantly between patients with IHD or MI and healthy individuals; however, we believe that ST2 could be used as an auxiliary diagnostic biomarker of HF.


2020 ◽  
pp. 1-15 ◽  
Author(s):  
Mohammad Sharifzadeh ◽  
Minoo Bagheri ◽  
John R. Speakman ◽  
Kurosh Djafarian

Abstract Physical activity questionnaires (PAQ) could be suitable tools in free-living people for measures of physical activity, total and activity energy expenditure (TEE and AEE). This meta-analysis was performed to determine valid PAQ for estimating TEE and AEE using doubly labelled water (DLW). We identified data from relevant studies by searching Google Scholar, PubMed and Scopus databases. This revealed thirty-eight studies that had validated PAQ with DLW and reported the mean differences between PAQ and DLW measures of TEE (TEEDLW − TEEPAQ) and AEE (AEEDLW − AEEPAQ). We assessed seventy-eight PAQ consisting of fifty-nine PAQ that assessed TEE and thirty-five PAQ that examined AEE. There was no significant difference between TEEPAQ and TEEDLW with a weighted mean difference of –243·3 and a range of –841·4 to 354·6 kJ/d, and a significant weighted mean difference of AEEDLW – AEE PAQ 414·6 and a range of 78·7–750·5. To determine whether any PAQ was a valid tool for estimating TEE and AEE, we carried out a subgroup analysis by type of PAQ. Only Active-Q, administered in two seasons, and 3-d PA diaries were correlated with TEE by DLW at the population level; however, these two PAQ did not demonstrate an acceptable limit of agreement at individual level. For AEE, no PAQ was correlated with DLW either at the population or at the individual levels. Active-Q and 3-d PA diaries were identified as the only valid PAQ for TEE estimation. Further well-designed studies are needed to verify this result and identify additional valid PAQ.


2009 ◽  
Vol 89 (1) ◽  
pp. 9-25 ◽  
Author(s):  
Luciana G Macedo ◽  
Christopher G Maher ◽  
Jane Latimer ◽  
James H McAuley

BackgroundPrevious systematic reviews have concluded that the effectiveness of motor control exercise for persistent low back pain has not been clearly established.ObjectiveThe objective of this study was to systematically review randomized controlled trials evaluating the effectiveness of motor control exercises for persistent low back pain.MethodsElectronic databases were searched to June 2008. Pain, disability, and quality-of-life outcomes were extracted and converted to a common 0 to 100 scale. Where possible, trials were pooled using Revman 4.2.ResultsFourteen trials were included. Seven trials compared motor control exercise with minimal intervention or evaluated it as a supplement to another treatment. Four trials compared motor control exercise with manual therapy. Five trials compared motor control exercise with another form of exercise. One trial compared motor control exercise with lumbar fusion surgery. The pooling revealed that motor control exercise was better than minimal intervention in reducing pain at short-term follow-up (weighted mean difference=−14.3 points, 95% confidence interval [CI]=−20.4 to −8.1), at intermediate follow-up (weighted mean difference=−13.6 points, 95% CI=−22.4 to −4.1), and at long-term follow-up (weighted mean difference=−14.4 points, 95% CI=−23.1 to −5.7) and in reducing disability at long-term follow-up (weighted mean difference=−10.8 points, 95% CI=−18.7 to −2.8). Motor control exercise was better than manual therapy for pain (weighted mean difference=−5.7 points, 95% CI=−10.7 to −0.8), disability (weighted mean difference=−4.0 points, 95% CI=−7.6 to −0.4), and quality-of-life outcomes (weighted mean difference=−6.0 points, 95% CI=−11.2 to −0.8) at intermediate follow-up and better than other forms of exercise in reducing disability at short-term follow-up (weighted mean difference=−5.1 points, 95% CI=−8.7 to −1.4).ConclusionsMotor control exercise is superior to minimal intervention and confers benefit when added to another therapy for pain at all time points and for disability at long-term follow-up. Motor control exercise is not more effective than manual therapy or other forms of exercise.


2021 ◽  
Author(s):  
Seyed A Raeissadat ◽  
Seyed M Rayegani ◽  
Mohammad R Sohrabi ◽  
Nafisseh Jafarian ◽  
Mohammad N Bahrami

Aim: Knee osteoarthritis is a common disabling disorder, with no curative treatment. This study aims to assess autologous conditioned serum effectiveness in its treatment. Materials & methods: Following a systematic search (2000–2020) on major databases and screening and filtering processes, eight articles were included in the final analyses. The pooled effect of visual analog scale (VAS) and the Western Ontario and McMaster Universities (WOMAC) variables was evaluated before and after the intervention. Results: The combined standardized mean difference for the global WOMAC score was -2.44 and the combined weighted mean difference was -22.92. The combined standardized mean difference for the VAS score was -3.77 and the combined weighted mean difference was -32.37 (p < 0.000). Conclusion: This meta-analysis reported that the autologous conditioned serum can reduce pain and improve function (VAS and WOMAC outcome measures) in patients with knee osteoarthritis.


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