Effect of polyphenols against complications of COVID-19: current evidence and potential efficacy

The COVID-19 pandemic that started in 2019 and resulted in significant morbidity and mortality continues to be a significant global health challenge, characterized by inflammation, oxidative stress, and immune system dysfunction.. Developing therapies for preventing or treating COVID-19 remains an important goal for pharmacology and drug development research. Polyphenols are effective against various viral infections and can be extracted and isolated from plants without losing their therapeutic potential. Researchers have developed methods for separating and isolating polyphenols from complex matrices. Polyphenols are effective in treating common viral infections, including COVID-19, and can also boost immunity. Polyphenolic-based antiviral medications can mitigate SARS-CoV-2 enzymes vital to virus replication and infection. Individual polyphenolic triterpenoids, flavonoids, anthraquinonoids, and tannins may also inhibit the SARS-CoV-2 protease. Polyphenol pharmacophore structures identified to date can explain their action and lead to the design of novel anti-COVID-19 compounds. Polyphenol-containing mixtures offer the advantages of a well-recognized safety profile with few known severe side effects. However, studies to date are limited, and further animal studies and randomized controlled trials are needed in future studies. The purpose of this study was to review and present the latest findings on the therapeutic impact of plant-derived polyphenols on COVID-19 infection and its complications. Exploring alternative approaches to traditional therapies could aid in developing novel drugs and remedies against coronavirus infection.

Effect of sesame supplementation on body composition and lipid profile in patients with type 2 diabetes: A systematic review and meta-analysis of randomized controlled trials

AIMS

The aim of this study was to conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) that evaluated the impact of sesame supplementation on body weight (BW), body mass index (BMI), triglycerides (TGs), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and high-density lipoprotein-cholesterol (HDL-C) in patients with type 2 diabetes mellitus (T2DM).

DATA SYNTHESIS

PubMed, Scopus, ISI Web of Science, and Embase were searched without any restrictions until September 2023.Only RCTs reporting the effects of sesame supplementation on body composition and lipid profiles were included, while observational studies and animal models were excluded. The methodological quality of the studies was assessed using the Cochrane risk of bias tool. Out of 997 studies identified, 10 were included in the systematic review and meta-analysis. Our meta-analysis suggested a significant association between sesame supplementation and reduction in TG (weighted mean difference (WMD): -37.61 mg/dl, 95 % CI: -61.48, 13.73), TC (WMD: -32.69 mg/dl, 95 % CI: -47.26, 18.12), and LDL-C (WMD: -28.72 mg/dl, 95 % CI: -44.68, 12.76). However, our meta-analysis indicated that the supplementary intake of sesame had no significant effect on HDL-C, BW, and BMI in patients with T2DM.

CONCLUSIONS

This study showed that sesame consumption significantly lowered TG, TC, and LDL-C levels, which may have contributed to the improvement of clinical symptoms in T2DM. However, given the limited number of trials included in the analysis, additional large-scale studies are needed to confirm the effects of sesame consumption on the lipid profile and body composition in patients with T2DM.

PROSPERO CODE

CRD42023460630.

Effect of Zinc Supplementation on Lipid Profile and Body Composition in Patients with Type 2 Diabetes Mellitus: A GRADE-Assessed Systematic Review and Dose-Response Meta-analysis

The aim of this systematic review and meta-analysis of randomized controlled trials (RCTs) is to investigate the overall effects of zinc supplementation on lipid profile and body composition such as body weight (BW), body mass index (BMI), triglycerides (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and high-density lipoprotein-cholesterol (HDL-C) in patients with type 2 diabetes mellitus (T2DM). Scopus, Web of Science, PubMed, and Embase databases were searched from inception through October, 2023. The I2 and Cochran's Q tests were used to assess heterogeneity between studies. Nineteen RCTs (n = 1357 participants) were included in the meta-analysis. Zinc supplementation significantly reduced TG (WMD = - 17.41 mg/dL; 95% CI: - 22.60, - 12.22; P < 0.001), TC (WMD: - 19.60 mg/dL; 95% CI: - 28.46, - 10.73, P < 0.001), LDL-C (WMD = - 8.80 mg/dL; 95% CI: - 14.80, - 2.81; P = 0.004), and BMI (WMD = - 0.53 kg/m2; 95% CI: - 1.05, - 0.01; P = 0.046) but not BW (WMD: - 0.51 kg, 95 % CI: - 1.99, 0.97, P = 0.498). Moreover, zinc supplementation increased HDL-C (WMD = 4.82 mg/dL; 95% CI: 0.88, 8.76; P = 0.016) in patients with T2DM. Our results propose that zinc supplementation may be an effective strategy for improving lipid profile and body composition in patients with T2DM.

Curcumin supplementation effect on liver enzymes in patients with nonalcoholic fatty liver disease: a GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials

CONTEXT

Clinical evidence from investigations of the effects of curcumin on liver enzymes in patients with nonalcoholic fatty liver disease (NAFLD) have led to inconsistent results.

OBJECTIVE

The aim of this systematic review and meta-analysis was to investigate the overall effects of curcumin and curcumin plus piperine supplementation on liver enzymes such as alanine aminotransferase (ALT), alkaline phosphatase (ALP), and aspartate aminotransferase (AST) in patients with NAFLD.

DATA SOURCES

The Scopus, Web of Science, PubMed, and Cochrane Library databases were searched from inception through July 2023, using search terms representing NAFLD and liver enzymes. Articles were screened independently by 2 researchers based on PICOS inclusion criteria.

DATA EXTRACTION

The following data were extracted: first author's name, study location, year of publication, mean age, study duration, study design, participants' sex, number of participants in each group, dose of curcumin supplementation, and ALT, ALP, and AST concentrations. Risk of bias was assessed using the Cochrane Collaboration's modified risk-of-bias tool.

DATA ANALYSIS

Fixed- or random-effects meta-analysis was performed to estimate the effects of curcumin on liver enzymes, considering heterogeneity across studies. The I2 and Cochran's Q tests were used to assess heterogeneity between studies.

RESULTS

Overall, 15 randomized controlled trials comprising 905 participants were eligible for this meta-analysis. Curcumin supplementation significantly reduced ALT (weighted mean difference [WMD], -4.10, 95%CI, -7.16 to -1.04) and AST (WMD, -3.27; 95%CI, -5.16 to -1.39), but not ALP (WMD, -0.49; 95%CI, -1.79 to 0.82). Curcumin plus piperine supplementation had no significant effect on ALT (WMD, -3.79; 95%CI, -13.30 to 5.72), and AST (WMD, -1.1; 95%CI, -3.32 to 1.09).

CONCLUSIONS

Curcumin supplementation improved AST and ALT levels compared with the control group. However, better-designed randomized controlled trials with larger sample sizes and of higher quality are needed to assess the effects of curcumin on ALP.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023448231.

Effects of marine-derived n-3 PUFA supplementation on soluble adhesion molecules: A systematic review and dose-response meta-analysis of randomized controlled trials

Long-chain n-3 poly unsaturated fatty acids have anti-inflammatory effects but their effects on serum levels of adhesion molecules are inconsistent and contradictory. In this updated systematic review and meta-analysis, marine sources of omega-3 fatty acids were pooled up to determine the effects of omega-3 supplementation on adhesion molecules. PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases (from inception to April 2023) were searched and all RCTs investigating the effects of marine sources of omega-3, on blood concentrations of adhesion molecules were included and a meta-analysis undertaken. Forty-two RCTs were included involving 3555 participants aged from 18 to 75 years. Meta-analysis of 38 arms from 30 RCTs reporting serum concentrations of vascular cell adhesion molecule-1 (VCAM-1) showed a significant reduction after omega-3 supplementation (WMD: -1.26, 95% CI: -1.88 to -0.64 ng/mL, P < 0.001). Meta-analysis of 40 arms from 30 RCTs reporting serum concentrations of intercellular adhesion molecule-1 (ICAM-1) revealed a reduction following omega-3 supplementation, although it was not significant (WMD: -1.76, 95%CI: -3.68 to 0.16 ng/mL, P = 0.07). Meta-analysis of 27 arms from 21 trials showed no effect on E-selectin (WMD: 0.01, 95%CI: -0.02 to 0.04 ng/mL, P = 0.62). Pooling 15 arms from 11 RCTs showed a marginally significant reducing effect on P-selectin concentrations (WMD: -2.67, 95%CI: -5.53 to 0.19 ng/mL, P = 0.06). A considerable decrease in VCAM concentration was observed after omega-3 supplementation in this meta-analysis with a trend to decreases in both ICAM and P-selectin levels, with effects that may be significant depending on study design, and there was no effect on E-selectin.

The effects of alpha lipoic acid (ALA) supplementation on blood pressure in adults: a GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials

Introduction

There have been various clinical studies on the effect of Alpha lipoic acid (ALA) supplementation on blood pressure (BP), but the findings from these are contradictory. Therefore, we performed a systematic review and dose-response meta-analysis to summarize the relation of ALA supplementation and systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults.

Methods

A comprehensive search was conducted in Medline (PubMed), Embase, Scopus, and ProQuest up to July 2023. Randomized controlled trials (RCTs) evaluating the effect of ALA on SBP and DBP were included. The pooled weighted mean difference (WMD) of included trials was estimated using a random-effects model. The dose-dependent effect was also assessed.

Results and discussion

A total of 11 RCTs with the participation of 674 patients were included. The result of the meta-analysis indicated that using ALA supplementation significantly reduced the SBP (WMD = -5.46 mmHg; 95% CI: -9.27, -1.65; p < 0.001) and DBP (WMD = -3.36 mmHg, 95% CI: -4.99, -1.74; p < 0.001). The ALA administrations significantly reduced SBP and DBP at the dosages of <800 mg/day, when administered for ≤12 weeks. The present meta-analysis revealed that ALA supplementation could exert favorable effects on SBP and DBP. Further well-designed studies with larger samples are needed to ascertain the long-term effects of ALA on BP.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=447658, identifier PROSPERO: CRD42023447658.

Selenium supplementation effect on glycemic control: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials

Results from different studies on the effects of selenium supplementation on glycemic control are still debated. To fill this knowledge gap, we investigated the overall effects of selenium supplementation on some glycemic parameters such as fasting blood sugar (FBS), hemoglobinA1c (HbA1c), fasting insulin, quantitative insulin sensitivity check index (QUICKI), and homeostatic model assessment of insulin resistance (HOMA-IR). A comprehensive literature search was conducted from inception to April 2023 on Scopus, Web of Science, PubMed, Google Scholar, and Cochrane databases. All randomized controlled trials (RCTs) which reported an effect of selenium supplementation on glycemic parameters were included. A random-effects model was used to estimate the weighted mean difference (WMD) and 95% CI for each outcome. Between-studies heterogeneity was assessed by the I2 and Cochran's Q test. 20 trials were included in the meta-analysis. Pooled analysis showed that selenium intake significantly reduced fasting insulin (WMD: -3.02 µIu/mL, 95% CI; -5.13, -0.90, P = 0.005) and increased QUICKI levels (WMD: 0.01, 95% CI: 0.01, 0.02, P = 0.005). However, selenium supplementation did not change FBS (WMD: -1.32 mg/dL, 95% CI; -4.02, 1.37, P = 0.332), HbA1c (WMD = 0.05%, 95% CI: -0.19, 0.28, p = 0.701), and HOMA-IR (WMD: -0.82, 95% CI; -2.14, 0.50, P = 0.223). Moreover, we found that there is a non-linear association between selenium supplementation dosage and FBS (P-nonlinearity = 0.008). In conclusion, our study findings indicate some benefits of selenium on fasting insulin, and QUICKI compared with placebo, but elicits no effect on HbA1c, HOMA-IR, and FBS. Further well-designed RCTs with larger samples are necessary to ascertain the effects of selenium supplementation on glycemic control.

Effect of nano-curcumin on various diseases: A comprehensive review of clinical trials

The antioxidant, anti-inflammatory, and antibacterial properties of curcumin have made it a valuable herbal product for improving various disorders, such as COVID-19, cancer, depression, anxiety, osteoarthritis, migraine, and diabetes. Recent research has demonstrated that encapsulating curcumin in nanoparticles might improve its therapeutic effects and bioavailability. To our knowledge, the efficacy of nano-curcumin on different aspects of health and disease has not been summarized in a study. Therefore, this review aimed to evaluate nano-curcumin's efficacy in various diseases based on the findings of clinical trials. In order to review publications focusing on nanocurcumin's impact on various diseases, four databases were searched, including PubMed, Scopus, Web of Science, and Google Scholar. This review highlights the potential benefits of nano-curcumin in improving a wide range of human diseases including COVID-19, neurological disorders, chronic disease, oral diseases, osteoarthritis, metabolic syndrome, and other diseases, especially as an adjunct to standard therapy and a healthy lifestyle.

Evaluation of Curcumin-Piperine Supplementation in COVID-19 Patients Admitted to the Intensive Care: A Double-Blind, Randomized Controlled Trial

BACKGROUND

Curcumin is a traditional remedy for diseases associated with hyper-inflammatory responses and immune system impairment. Piperine, a bioactive compound in black pepper, has the potential to enhance curcumin bioavailability. 0This study aims to examine the effect of the curcumin-piperine co-supplementation in patients infected with SARS-CoV-2 and admitted to the intensive care unit (ICU).

MATERIAL AND METHODS

In this parallel randomized, double-blind, placebo-controlled trial, 40 patients with COVID-19 admitted to ICU were randomized to receive three capsules of curcumin (500 mg)-piperine (5 mg) or placebo for 7 days.

RESULTS

After 1 week of the intervention, serum aspartate aminotransferase (AST) (p = 0.02) and C-reactive protein (CRP) (p = 0.03) were significantly decreased, and hemoglobin was increased (p = 0.03) in the curcumin-piperine compared to the placebo group. However, compared with the placebo, curcumin-piperine had no significant effects on the other biochemical, hematological, and arterial blood gas and 28-day mortality rate was three patients in each group (p = 0.99).

CONCLUSION

The study results showed that short-term curcumin-piperine supplementation significantly decreased CRP, AST, and increased hemoglobin in COVID-19 patients admitted to the ICU. Based on these promising findings, curcumin appears to be a complementary treatment option for COVID-19 patients, although some parameters were not affected by the intervention.

A plant-based dietary score and attention deficit/hyperactivity disorder in Iranian children: A case-control study

OBJECTIVE

Attention-deficit hyperactivity disorder (ADHD) is the most prevalent neurodevelopmental disorder with a prevalence of 5 % among children and adolescents worldwide. Plant foods have a protective effect against inflammation and oxidative stress which both are involved in psychiatric disorders pathophysiology including ADHD. Accordingly, we investigated the association between plant-based diet (PDI) and ADHD.

METHODS

This case-control study was conducted on 345children and adolescents 7-13 years old in Yazd, Iran. Subjects were categorized into the case (n = 113) and control groups (n = 232) based on matching age and sex. To diagnose ADHD, the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSMIV-TR) was used. Food frequency questionnaire was used to measure food intake. The association of PDI with ADHD was examined by logistic regression.

RESULTS

Children in the highest quartile of PDI compared to the lowest quartile had a higher energy and macronutrient intake, calcium, zinc, iron, vitamin B12, B6, and folic acid. After adjusting for potential confounders, a significant decreasing trend in the odds of ADHD across increasing quartiles of the PDI (P-trend = 0.001) was observed. In addition, children in the fourth quartile of PDI had 68 % lower odds of ADHD than the first quartile. This association remained significant after further adjustment for BMI (OR: 0.32;95 % CI: 0.13-0.79; P for trend: 0.001).

CONCLUSION

We found that PDI is associated with lower risk of ADHD in children. Cohort and clinical studies are necessary to approve our results.

The association between dairy products and the risk of COVID-19

BACKGROUND

The fast spread of the coronavirus disease 2019 (COVID-19) epidemic and its high mortality were quickly noticed by the health community. Dairy products have been recognized as part of a healthy diet that helps strengthen body immunity and prevent infections. The present study can provide a comprehensive picture of the associations between dairy products consumption and COVID-19 incidence.

METHODS

This study was undertaken on 8801 adults participants of Yazd Health Study (YaHS) and Taghzieh Mardom-e-Yazd (TAMIZ) study aged 20 to 70 years. Data on dietary intakes were obtained using a validated food frequency questionnaire (FFQ). Multivariable logistic regression analysis was used to assess the association between dairy consumption and COVID-19.

RESULT

Our finding indicated that moderate intake of total dairy (OR: 0.63, 95% CI 0.46-0.87, P-trend = 0.97) could reduce the odds of COVID-19 and higher intake of low-fat dairy products (OR: 0.51 CI: 0.37-0.69, p-trend < 0.001) and low-fat milk (OR: 0.47 CI: 0.35-0.64, p-trend < 0.001) had a protective effect on COVID-19 after adjusting for confounders. However, higher intake of high-fat-dairy-product (OR: 1.40 CI: 1.09-1.92, p-trend = 0.03), high-fat milk (OR: 1.54 CI: 1.20-1.97, p-trend < 0.001), total yogurt (OR: 1.40 CI: 1.04-1.89, p-trend = 0.01), cheese (OR: 1.80 CI: 1.27-2.56, p-trend = 0.001), and butter (OR: 1.80 CI: 1.04-3.11, p-trend = 0.02) were related to increase the odds of COVID-19.

CONCLUSIONS

Moderate intake of total dairy could reduce odds of COVID-19 by 37% and, a higher intake of low-fat dairy products had a protective role on COVID-19. Although our study has promising results, stronger clinical studies are needed.