The effect of pomegranate on oxidative stress parameters: A systematic review and meta-analysis

Objective: Pomegranate contains remarkable amounts of phenolic ingredients and it has been related to the antioxidant capacity of this fruit. Several primary studies show that pomegranate intake can improve antioxidant status. The objective of this systematic review and meta-analysis consisted in investigating the effect of pomegranate on oxidative stress (OS) parameters. Methods: A comprehensive electronic database search in Scopus, Web of science, Embase, Cochrane library and Medline was performed to identify eligible randomized controlled trials (RCTs). A meta-analysis of included studies was performed on selected variables using a random-effects model. Quality assessment was conducted by means of Cochrane risk of bias assessment tool. Results: Systematic search yielded 575 references. A total of 11 RCTs reporting data from 484 participants included. Meta-analysis of data from 11 included RCTs did not support convincing evidence as to a significant increasing effect of pomegranate intake in TAC (SMD: 0.43 ; 95 %CI: -0.19, 1.06), Gpx (SMD: 0.18, 95 % CI: -0.25, 0.62, p = 0.4) and paraxonase (SMD: 0.36, 95 % CI: -0.50, 1.22, p= 0.41) as well as not significant decrease in Malondialdehyde (MDA) (SMD: -0.81, 95 % CI: -1.79, 0.09, P = 0.08). Conclusion: Future well-designed clinical trials are needed before definite conclusive claims can be made about the effect of pomegranate on OS parameters. Keywords: Pomegranate, Oxidative stress, Antioxidant, Randomized clinical trial

Effect of saffron supplementation on oxidative stress parameters: A systematic review and meta‐analysis of randomized placebo‐controlled trials

Oxidative stress (OS), the absence of equilibrium between prooxidants and antioxi dants in the body, has been shown to play a pivotal role in the initiation and pro gression of many diseases. Saffron has been noted for its antioxidant capacity and can be used to improve OS parameters in unhealthy patients. Our aim was to evalu ate the efficacy of saffron supplementation on OS parameters in unhealthy patients in randomized controlled trials (RCTs). We searched Medline, EMBASE, Cochrane CENTRAL, Scopus, and Web of Science without language restrictions for RCTs up until April 2021. Studies were included if they compared any form of saffron sup plementation to placebo or no supplementation on OS parameters in unhealthy pa tients. Using a random-effects model with calculated standardized mean difference (SMD) and 95% confidence intervals (CI), we quantitatively synthesized the data. Heterogeneity was assessed using Cochrane's I 2 values. Ten randomized controlled trials were eligible for this review. Seven were included in the meta-analysis and indicated an association between saffron intake and a statistically significant decrease in malondialdehyde (MDA) levels (SMD: −0.40; 95% CI: −0.63, −0.17; I 2 = 32.6%) and a significant increase in total antioxidant capacity (TAC, SMD: 0.24; 95% CI: 0.05, 0.42; I 2 = 00.0%). Saffron intake was shown to significantly impact MDA and TAC, indicating its beneficial properties in improving OS in unhealthy patients. However, additional RCTs are required to evaluate the effect on other OS parameters.info:eu-repo/semantics/publishedVersio

The effect of almond intake on cardiometabolic risk factors, inflammatory markers, and liver enzymes: A systematic review and meta‐analysis

Almond intake may be correlated with improvements in several cardiometabolic parameters, but its effects are controversial in the published literature, and it needs to be comprehensively summarized. We conducted a systematic search in several international electronic databases, including MEDLINE, EMBASE, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, and until April 2021 to identify randomized controlled trials that examined the effects of almond consumption on cardiometabolic risk factors, inflammatory markers, and liver enzymes. Data were pooled using the random-effects model method and presented as standardized mean differences (SMDs) with 95% confidence intervals (CIs). Twenty-six eligible trials were analyzed (n = 1750 participants). Almond intake significantly decreased diastolic blood pressure, total cholesterol, triglyceride, low-density lipoprotein (LDL), non-high-density lipoprotein (HDL), and very LDL (p .05). The current body of evidence supports the ingestion of almonds for their beneficial lipid-lowering and antihypertensive effects. However, the effects of almonds on antiinflammatory markers, glycemic control, and hepatic enzymes should be further evaluated via performing more extensive randomized trials.info:eu-repo/semantics/publishedVersio

Resveratrol supplementation and acute pancreatitis: A comprehensive review

Resveratrol, a natural polyphenolic ingredient extracted from herbs, suppresses oxidative stress and inflammation. We performed a comprehensive review to find any evidence about the effects of Resveratrol on acute pancreatitis (AP). Resveratrol has been found to directly impact cytokine generation. As these factors play a crucial role in the pathophysiology of AP, resveratrol might attenuate AP and its complications. Mechanistically, resveratrol exerts its pharmacological effects through anti-inflammatory and antioxidant mechanisms via interaction with different signaling molecules and transcription factors. Indeed, resveratrol might prove to be an effective therapeutic component for AP treatment in the future. In this review, we shed light on potential most recent pathways through which resveratrol might impact the management and control of AP

The Modulatory Bioeffects of Pomegranate (<i>Punica granatum</i> L.) Polyphenols on Metabolic Disorders: Understanding Their Preventive Role against Metabolic Syndrome

Modern research achievements support the health-promoting effects of natural products and diets rich in polyphenols. Pomegranate (PG) (Punica granatum L.) contains a considerable number of bioactive compounds that exert a broad spectrum of beneficial biological activities, including antimicrobial, antidiabetic, antiobesity, and atheroprotective properties. In this context, the reviewed literature shows that PG intake might reduce insulin resistance, cytokine levels, redox gene expression, blood pressure elevation, vascular injuries, and lipoprotein oxidative modifications. The lipid parameter corrective capabilities of PG-ellagitannins have also been extensively reported to be significantly effective in reducing hyperlipidemia (TC, LDL-C, VLDL-C, and TAGs), while increasing plasma HDL-C concentrations and improving the TC/HDL-C and LDL-C/HDL-C ratios. The health benefits of pomegranate consumption seem to be acheived through the amelioration of adipose tissue endocrine function, fatty acid utilization, GLUT receptor expression, paraoxonase activity enhancement, and the modulation of PPAR and NF-κB. While the results from animal experiments are promising, human findings published in this field are inconsistent and are still limited in several aspects. The present review aims to discuss and provide a critical analysis of PG’s bioeffects on the components of metabolic syndrome, type-2 diabetes, obesity, and dyslipidemia, as well as on certain cardiovascular-related diseases. Additionally, a brief overview of the pharmacokinetic properties, safety, and bioavailability of PG-ellagitannins is included

The effect of Conjugated Linoleic Acid intake on oxidative stress parameters and antioxidant enzymes: A systematic review and meta-analysis of randomized clinical trials

Conjugated Linoleic Acid (CLA) are thought to pose beneficial effects on inflammatory responses and oxidative stress (OS). Thus, the present systematic review and meta-analysis of randomized controlled trials (RCTs) aimed to assess the net effects of CLA supplementation on various OS parameters and antioxidant enzymes. PubMed/ MEDLINE, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials databases were searched for publications on CLA supplementation effects on OS parameters up to March 2021. The data extracted from eligible studies were expressed as standardized mean difference with 95% confidence intervals and then combined into meta-analysis using the random-effects model. Overall, 11 RCTs (enrolling 586 participants) met the inclusion criteria and were included in meta-analysis; however, since those trials evaluated different OS parameters, meta-analysis was carried out considering different sets for each parameter separately. According to our results, CLA supplementation significantly increases 8-iso-PGF(2 alpha )urinary concentration (SMD: 2; 95% CI: 0.74, 3.27; I-2 = 87.7%). On contrary, the intervention does not seem to change 15-keto-dihydro-PGF(2 alpha )urinary concentration, nor the serum levels of CAT, SOD, GPx and MDA. Taken all together, CLA supplementation does not appear to have substantial effects on OS markers in general; albeit due to relatively small sample size and high level of heterogeneity between studies, the obtained findings should be interpreted with caution. Further large well-designed RCTs, investigating the impact of CLA and including various groups of patients, are still needed.info:eu-repo/semantics/publishedVersio

Effect of Calcium and Vitamin D Co-supplementation on Blood Pressure: A Systematic Review and Meta-Analysis

Purpose: Vitamin D and calcium insufficiency has been related to elevated blood pressure (BP) and cardiovascular complications. This systematic review and meta-analysis investigates the effect of calcium and vitamin D co-supplementation on BP. Methods: A systematic search was conducted of electronic databases, including Web of Sciences, MEDLINE, Scopus, EMBASE, and the Cochrane Library, along with searches of gray literature and reference lists from included trials. There were no language restrictions, and the databases were searched from inception to October 2019. Randomized controlled trials, using calcium and vitamin D co-supplementation and reporting mean systolic BP and/or diastolic BP (DBP) with SDs, were included in the systematic review. Articles were evaluated independently by 2 researchers based on inclusion and exclusion criteria. A random effects model was conducted to synthesize the data. Findings: Eight trials were included in the meta-analysis. Meta-analysis of these 8 trials indicated a nonsignificant reduction in systolic BP in the calcium and vitamin D co-supplementation group compared with control (standardized mean difference, −0.23; 95% CI, −0.52 to 0.06). Conversely, there was a statistically significant decrease in DBP (standardized mean difference, −0.29; 95% CI, −0.55 to −0.02). Subgroup analysis suggested that young adults achieve a greater reduction in DBP than other age groups. Implications: Calcium and vitamin D co-supplementation can modulate DBP and should be investigated more specifically in large, well-designed trials of hypertensive populations

Effect of melatonin supplementation on oxidative stress parameters: A systematic review and meta-analysis

Background: Oxidative stress, defined as an imbalance between pro-oxidants and neutralizing antioxidants within the body, is a growing public health concern. Oxidative stress is involved in the progression of nearly all chronic diseases. Melatonin has been suggested to reduce oxidative stress by its potential radical scavenging properties. Objective: To determine the efficacy and safety of melatonin as a therapy for the improvement of oxidative stress parameters in randomized controlled trials. Methods: A systematic database search using Scopus, PubMed/Medline, EMBASE, Web of Science, the Cochrane Controlled Register of Trials and clinicaltrials.gov (https://clinicaltrials.gov) for studies published up to July 2020 was conducted. We included studies which investigated the effect of supplemental melatonin compared to placebo on oxidative stress parameters in unhealthy patients. Quantitative data synthesis was conducted using a random-effects model with standard mean difference (SMD) and 95 % confidence intervals (CI). Cochrane's Q and I2 values were used to evaluate heterogeneity. Results: A total of 12 randomized controlled trials (RCTs) were eligible. The meta-analysis indicated an association between melatonin intake and a significant increase in total antioxidant capacity (TAC) (SMD: 0.76; 95 % CI: 0.30, 1.21; I2 = 80.1 %), glutathione (GSH) levels (SMD: 0.57; 95 % CI: 0.32, 0.83; I2 = 15.1 %), superoxide dismutase (SOD) (SMD: 1.38; 95 % CI: 0.13, 2.62; I2 = 86.9 %), glutathione peroxidase (GPx) (SMD: 1.36; 95 % CI: 0.46, 2.30; I2 = 89.3 %), glutathione reductase (GR) (SMD: 1.21; 95 % CI: 0.65, 1.77; I2 = 00.0 %) activities, and a significant reduction in malondialdehyde (MDA) levels (SMD: -0.79; 95 % CI: -1.19, -0.39; I2 = 73.1 %). Melatonin intake was not shown to significantly affect nitric oxide (NO) levels (SMD: -0.24; 95 % CI: -0.61, 0.14; I2 = 00.0 %) or catalase (CAT) activity (SMD: -1.38; 95 % CI: -1.42, 4.18; I2 = 96.6 %). Conclusion: Melatonin intake was shown to have a significant impact on improving Oxidative stress parameters. However, future research through large, well-designed randomized controlled trials are required to determine the effect of melatonin on oxidative stress parameters in different age groups and different disease types

Effect of ginger (Zingiber officinale) on inflammatory markers: A systematic review and meta-analysis of randomized controlled trials

The aim of this systematic review and meta-analysis was to investigate the efficacy of ginger supplementation on circulating levels of C-reactive protein (CRP), high sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α), soluble intercellular adhesion molecule (sICAM), and interleukin-6 (IL-6) concentrations in randomized controlled trials (RCTs). The search included PubMed-Medline, EMBASE, Scopus, Web of Science and Cochrane Library databases to identify randomized clinical trials on the effect of ginger supplementation on circulation levels of CRP, hs-CRP, IL-6, sICAM, and TNF-α published up until February 1st, 2020. We did not restrict articles based on language of publication. Standard mean differences and 95% confidence intervals were calculated for net changes in inflammatory mediators using a random-effects model. Sixteen RCTs comprising 1010 participants were found to be eligible for this meta-analysis. There was a significant reduction of circulating CRP (SMD: −5.11, 95% CI: −7.91, −2.30, I2 = 98.1%), hs-CRP (SMD: −0.88, 95% CI: −1.63, −0.12, I2 = 90.8%) and TNF-α levels (SMD: −0.85, 95% CI: −1.48, −0.21, I2 = 89.4%) following ginger supplementation. However, meta-analysis results did not show any significant impact of ginger supplementation on IL-6 (SMD: −0.45, 95% CI: −1.29, 0.38, I2 = 89.2%), and sICAM levels (SMD: −0.05, 95% CI: −0.36, 0.26, I2 = 00.0%). This systematic review and meta-analysis of RCTs demonstrates a significant impact of ginger in lowering circulating CRP, hs-CRP and TNF-α levels. Large-scale RCTs are still needed to draw concrete conclusions about the effect of ginger on other inflammatory mediators

Effects of Melissa officinalis (Lemon Balm) on cardio‐metabolic outcomes: A systematic review and meta‐analysis

Recent evidence indicates a beneficial effect ofMelissa officinalis(MO) intake on several chronic diseases. However, the effects of MO intake have not yet been systematically reviewed. Therefore, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of MO intake and focused on several cardiometabolic outcomes. MEDLINE, Scopus, EMBASE, Web of Science and the Cochrane Central Register of Controlled Trials were searched for MO-RCTs evaluating cardiometabolic outcomes. Random-effects meta-analyses estimated the pooled standardized mean differences (SMD) between intervention and control groups. Risk of bias was assessed with the Cochrane Collaboration's tool for assessing the risk of bias in RCTs. Seven RCTs were finally deemed eligible. MO intake was associated with a reduced total cholesterol (TC) (SMD: -0.26; 95% CI: -0.52, -0.01;I-2= 13.7%;k= 6) and a reduced systolic blood pressure (SBP) (SMD: -0.56; 95% CI: -0.85, -0.27;I-2= 00.0%;k= 3). MO intake was not associated with statistically significant changes in triglycerides, low-density lipoprotein, diastolic blood pressure, high sensitivity c-reactive protein levels, fasting blood sugar, HbA1c, insulin or high-density lipoprotein levels. No serious adverse events were reported. The risk of bias was high in a considerable amount of studies. Our study suggests that MO is a safe supplement with beneficial effects on TC and SBP. However, the findings of our study must be seen in the light of major limitations such as a low number of included studies and a serious risk of bias. High-quality RCTs are needed for firm conclusions concerning the effects of MO on cardiometabolic outcomes. Keywords:blood pressure; cardiometabolic; cholesterol; Melissa officinali