Effect of propolis supplementation on C-reactive protein levels and other inflammatory factors: A systematic review and meta-analysis of randomized controlled trials

Propolis: A comprehensive review on the nature's polyphenolic wonder

Propolis, a resinous substance produced by honeybees, has been utilized in traditional medicine for centuries due to its diverse biological activities. This review explores the phytochemical composition, therapeutic applications, and potential health benefits of propolis. Comprising a complex mixture of resins, waxes, essential oils, and pollen, propolis exhibits significant antimicrobial, antioxidant, anti-inflammatory, immunomodulatory, and anticancer properties. The phytochemical content of propolis varies with its botanical and geographical origins, influencing its bioactivity. Propolis has shown promise in wound healing, oral health, cardiovascular protection, neuroprotection, hepatoprotection, and gastrointestinal health. Despite its therapeutic potential, challenges such as standardization, quality control, and regulatory issues need to be addressed. Future research should focus on elucidating the mechanisms of action, optimizing extraction methods, and conducting extensive clinical trials to validate its efficacy and safety. Sustainable production and conservation efforts are essential to ensure the continuous supply of high- quality propolis. This review highlights the need for interdisciplinary research to fully harness the potential of propolis in modern medicine.

Propolis supplementation on inflammatory and oxidative stress biomarkers in adults: a systematic review and meta-analysis of randomized controlled trials

Background

Although a large number of trials have observed the anti-inflammatory properties of propolis, the currently available research remains controversial regarding its beneficial health effects. Hence, the purpose of this study was to examine the effect of propolis on inflammatory and oxidative stress markers in adults.

Methods

A comprehensive search was performed in Scopus, Web of Science, and PubMed/Medline to find relevant randomized controlled trials (RCTs) until January 2024. The overall effect sizes were calculated using the random-effects model and expressed as weighted mean differences (WMD) with a 95% confidence interval (CI). The possible heterogeneity between included trials was assessed by performing Cochran's Q test.

Results

In total, 27 trials with 29 treatment arms were eligible for inclusion in this review. This meta-analysis revealed that propolis consumption led to a significant decrease in C-reactive protein (CRP) (WMD: -1.23; 95%CI: -1.76, -0.69; p < 0.001), Interleukin-6 (IL-6) (WMD: -1.52; 95%CI: -2.10, -0.93; p < 0.001), Tumor necrosis factor-α (WMD: -1.15; 95%CI: -1.75, -0.55; p < 0.001), and Monocyte chemoattractant protein-1 (MCP-1) (WMD: -35.33; 95%CI: -50.28, -20.37; p < 0.001), and a significant increase in total antioxidant capacity (TAC) (WMD: 0.32; 95%CI: 0.12, 0.51; p = 0.001), Glutathione (GSH) (WMD: 4.71; 95%CI: 3.17, 6.25; p < 0.001), and Glutathione peroxidase (GPx) (WMD: 44.75; 95%CI: 5.10, 84.40; p = 0.02). However, there were no significant effects on IL-10, IL-2, IL-8, pro-oxidant-antioxidant balance (PAB), malondialdehyde (MDA), and superoxide dismutase (SOD) in comparison to the control group.

Conclusion

Propolis supplementation appears effective in reducing inflammation and oxidative stress by enhancing antioxidant capacity and reducing specific inflammatory markers. However, variations in study designs, dosages, and participant characteristics contribute to the heterogeneity of results. Further well-designed RCTs are needed to confirm these findings and determine the optimal dosage and long-term effects. Given its potential anti-inflammatory and antioxidant properties, propolis may serve as a complementary approach in managing inflammation-related conditions, though its clinical application requires further validation.

Systematic review registration

https://clinicaltrials.gov/, identifier CRD42023474033.

The impact of propolis supplementation on inflammatory biomarkers: A meta-analysis and systematic review of randomized controlled clinical trials

Recent interventional investigations suggest the beneficial impact of propolis supplementation on inflammatory biomarkers; however, the results have not been summarized in a comprehensive meta-analysis. We conducted this meta-analysis to summarize all available data and provide clear evidence for whether propolis supplementation affects inflammatory biomarkers. This systematic review with meta-analysis was performed by searching databases (PubMed/Medline, Web of Science, Scopus, and Embase) until February 2024. It included randomized clinical trials (RCTs) assessing the effects of propolis supplementation on inflammatory biomarkers in adults. This review included 20 RCTs with a total of 1139 participants. The propolis supplementation significantly reduced IL-6 (WMD = -2.48; 95 % CI: -4.62, -0.34; P = 0.023) and TNF-α (WMD = -0.86; 95 % CI: -1.45, -0.26; P = 0.005) compared with control groups. Although the CRP concentration was not reduced (WMD = 0.01; 95 % CI: -0.03, 0.05, P = 0.646), a significant reduction in CRP levels was revealed in supplementation durations ≥ 10 weeks. These results suggest that propolis has a beneficial effect on TNF-α and IL-6 levels and may be an effective adjunctive therapy for diseases where inflammation is a key factor in the etiology. Due to the limited number of studies, clinical diversity, and other limitations, it is necessary to conduct more high-quality studies to provide more precise and comprehensive recommendations.

Propolis supplementation can reduce serum level of interleukin-6, C-reactive protein, and tumor necrosis factor-α: an updated systematic review and dose-response meta-analysis on randomized clinical trials

BACKGROUND

New evidence suggested that propolis might reduce serum levels of inflammatory mediators; therefore, in this study we aimed to prove the potential effect of propolis on serum levels of interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-alpha (TNF-α) through conducting a systematic review and meta-analysis.

METHODS

Databases including PubMed, ClinicalTrials.gov, Scopus, Cochrane Library, and ISI Web of Science were searched until October 2023. In the present meta-analysis, we detected the overall effect sizes using extracted standard mean differences (SMD) and the standard deviations (SDs) from both study groups through DerSimonian and Laird method. Exploring the statistical heterogeneity was done through Cochran's Q test and I-squared statistic.

RESULTS

In total, seventeen and sixteen studies were included in the systematic review and meta-analysis, respectively. The overall estimate indicated that the propolis significantly reduced serum levels of IL-6 (SMD = -3.47, 95% confidence interval (95%CI): -5.1, -1.84; p < 0.001), CRP (SMD= -1.73, 95%CI: -2.82, -0.65; p = 0.002), and TNF-α (SMD= -1.42, 95%CI= -2.15, -0.68; p < 0.001). These results also revealed geographical region and propolis dose were the critical points to get the beneficial effects.

CONCLUSION

According to our result, propolis supplementation can decrease serum levels of IL-6, CRP, and TNF-α; therefore, it might be considered as complementary therapy for the treatment of certain chronic diseases.

Using the concept of food as medicine to mitigate inflammation in patients undergoing peritoneal dialysis

The most common kidney replacement therapy (KRT) worldwide is hemodialysis (HD), and only 5%-10% of patients are prescribed peritoneal dialysis (PD) as KRT. Despite PD being a different method, these patients also present particular complications, such as oxidative stress, gut dysbiosis, premature aging, and mitochondrial dysfunction, leading to an inflammation process and high cardiovascular mortality risk. Although recent studies have reported nutritional strategies in patients undergoing HD with attempts to mitigate these complications, more information must be needed for PD patients. Therefore, this review provides a comprehensive analysis of recent studies of nutritional intervention to mitigate inflammation in PD patients.

The effect of Brazilian Green Propolis extract on inflammation in patients with chronic kidney disease on peritoneal dialysis: A randomised double-blind controlled clinical trial

BACKGROUND

Chronic kidney disease (CKD) patients on dialysis display a low-grade systemic inflammatory burden. Nutritional interventions designed to activate the cytoprotective nuclear factor erythroid-2-related factor 2 (Nrf2) and inhibit nuclear factor-kB (NF-κB) have been proposed to mitigate this burden. Several bioactive compounds have been investigated to achieve this, including propolis, a resin produced by Apis mellifera bees. Considering the safety and efficacy of propolis, it could be a strategy to benefit these patients. Still, there are no studies using propolis in patients with CKD on peritoneal dialysis (DP), and clinical studies to support this application are lacking.

HYPOTHESIS/PURPOSE

The objective and novelty of the present study are to evaluate the effects of propolis supplementation on inflammatory markers in patients with CKD on PD.

STUDY DESIGN

A longitudinal, double-blind, placebo-controlled trial with CKD patients on PD.

METHODS

The patients were randomised into two groups: propolis that received four capsules of 100 mg (400 mg/day), containing concentrated and standardised dry EPP-AF® Brazilian green propolis extract) or placebo, four capsules of 100 mg (400 mg/day), of magnesium stearate, silicon dioxide, and microcrystalline cellulose, for two months. Plasma levels of inflammatory cytokines, including tumour necrosis factor (TNF-α) and interleukin-6 (IL-6), were evaluated by ELISA. Quantitative real-time PCR analyses were performed to evaluate the transcriptional expression levels of Nrf2 and NF-κB in peripheral blood mononuclear cells (PBMCs). Plasma malondialdehyde (MDA) levels, a lipid peroxidation marker, was measured as thiobarbituric acid reactive substances (TBARS). Routine biochemical markers, including C-reactive protein (CRP), were analysed using commercial kits. Carotid Intima-Media Thickness (CIMT) was measured with a doppler ultrasonography device. The study was registered on ClinicalTrials.gov under the number NCT04411758.

RESULTS

A total of 19 patients completed the study, ten patients in the propolis group (54 ± 1.0 years, five men, 7.2  (5.1) months on PD) and 9 in the placebo group (47.5 ± 15.2 years, three men, 10.8  (24.3) months on PD). The plasma levels of TNF-α reduced significantly (p = 0.02), and expression of Nrf2 showed a trend to increase (p = 0.07) after propolis supplementation.

CONCLUSION

EPP-AF® Green Propolis extract (400 mg/day) supplementation for two months appears as a potential strategy to mitigate inflammation, reducing TNF-α plasma levels in CKD patients on PD.

Evaluation of Chemical Composition, Sun Protection Factor and Antioxidant Activity of Lithuanian Propolis and Its Plant Precursors

The growing interest in polyphenols of natural origin and their plant sources encourages the study of their chemical composition and biological activity. Propolis is widely used as a source of phenolic compounds. The aim of this study is to evaluate and compare the chemical composition, antioxidant activity and sun protection factor (SPF) of the ethanolic extracts of the poplar buds, birch buds and pine buds of propolis plant precursors collected in Lithuania. The IC50 concentration of the extracts was evaluated using DPPH and ABTS methods. Extracts of poplar buds, birch buds and propolis showed a lower IC50 concentration by ABTS and DPPH methods compared with pine buds extracts. Poplar buds and propolis extracts showed the highest SPF value, while birch and pine buds extracts showed a lower SPF value. High-performance liquid chromatography (HPLC) analysis results showed that phenolic acids, such as p-coumaric acid and cinnamic acid, and flavonoids, such as pinobanksin and pinocembrin, were identified in all the tested extracts. Salicin has been identified only in poplar buds extracts. The results of antioxidant activity showed that propolis poplar and birch buds are a promising source of biologically active polyphenols.

The Role of Nuclear Factor-Kappa B in Fibrinogen-Induced Inflammatory Responses in Cultured Primary Neurons

Traumatic brain injury (TBI) is an inflammatory disease associated with a compromised blood-brain barrier (BBB) and neurodegeneration. One of the consequences of inflammation is an elevated blood level of fibrinogen (Fg), a protein that is mainly produced in the liver. The inflammation-induced changes in the BBB result in Fg extravasation into the brain parenchyma, creating the possibility of its contact with neurons. We have previously shown that interactions of Fg with the neuronal intercellular adhesion molecule-1 and cellular prion protein induced the upregulation of pro-inflammatory cytokines, oxidative damage, increased apoptosis, and cell death. However, the transcription pathway involved in this process was not defined. The association of Fg with the activation of the nuclear factor-κB (NF-κB) and the resultant expression of interleukin-6 (IL-6) and C-C chemokine ligand-2 (CCL2) were studied in cultured primary mouse brain cortex neurons. Fg-induced gene expression of CCL2 and IL-6 and the expression of NF-κB protein were increased in response to a specific interaction of Fg with neurons. These data suggest that TBI-induced neurodegeneration can involve the direct interaction of extravasated Fg with neurons, resulting in the overexpression of pro-inflammatory cytokines through the activation of transcription factor NF-κB. This may be a mechanism involved in vascular cognitive impairment during neuroinflammatory diseases.

The Suitability of Propolis as a Bioactive Component of Biomaterials

Propolis is a resinous product collected by bees from plant exudates to protect and maintain hive homeostasis. Propolis has been used therapeutically for centuries as folk medicine. Modern research investigating the diversity of the chemical composition and plant sources, biological activity, extraction processes, analytical methods, and therapeutic properties in clinical settings have been carried out extensively since the 1980s. Due to its antimicrobial, anti-inflammatory, and immuno-modulator properties, propolis appears to be a suitable bioactive component to be incorporated into biomaterials. This review article attempts to analyze the potential application of propolis as a biomaterial component from the available experimental evidence. The efficacy and compabitility of propolis depend upon factors, such as types of extracts and types of biomaterials. Generally, propolis appears to be compatible with hydroxyapatite/calcium phosphate-based biomaterials. Propolis enhances the antimicrobial properties of the resulting composite materials while improving the physicochemical properties. Furthermore, propolis is also compatible with wound/skin dressing biomaterials. Propolis improves the wound healing properties of the biomaterials with no negative effects on the physicochemical properties of the composite biomaterials. However, the effect of propolis on the glass-based biomaterials cannot be generalized. Depending on the concentration, types of extract, and geographical sources of the propolis, the effect on the glass biomaterials can either be an improvement or detrimental in terms of mechanical properties such as compressive strength and shear bond strength. In conclusion, two of the more consistent impacts of propolis across these different types of biomaterials are the enhancement of the antimicrobial and the immune-modulator/anti-inflammatory properties resulting from the combination of propolis and the biomaterials.

Effects of Ethanol Extract of Propolis on Repair Optic Nerve Damage in a Rat Model for Diabetes Mellitus (Study of MDA, CRP, Caspase-3, and TGF-β Expression and Histopathological Changes on Optic Nerve Damage)

Purpose Hyperglycemia in diabetes increases oxidative stress in the body. It causes optic nerve damage and risk of glaucoma. In this study, we evaluated and analyzed the effect of propolis ethanol extract on repair of optic nerve damage in a rat model for Diabetes Mellitus. Study Design Laboratory experimental using the posttest only control group design was used in this study. Methods A total of 28 male Wistar rat were randomly divided into the following four groups namely control (K1), diabetes mellitus (K2), diabetes mellitus with propolis treatment (100 mg/kg) (P1) and diabetes mellitus with propolis treatment (200 mg/kg) (P2). Statistical analysis used ANOVA and Kruskal Wallis with a significance of p < 0.05. Results The results showed that Gunung Lawu propolis significantly reduced serum glucose levels, malondialdehyde levels and C-reactive protein levels (p<0.01). Furthermore, propolis extract significantly decreased caspase-3 expression and TGF-β expression (p<0.05) in the optic nerve. Propolis can significantly repair optic nerve damage (optic nerve necrosis, thinning of the retinal nerve fiber layer and retinal ganglion cell apoptosis (p < 0.01). Conclusion The final results showed that most of the beneficial effects of propolis were mediated by the reduction of blood glucose levels in diabetic rat.

The antiviral and immunomodulatory activities of propolis: An update and future perspectives for respiratory diseases

Propolis is a complex natural product that possesses antioxidant, anti-inflammatory, immunomodulatory, antibacterial, and antiviral properties mainly attributed to the high content in flavonoids, phenolic acids, and their derivatives. The chemical composition of propolis is multifarious, as it depends on the botanical sources from which honeybees collect resins and exudates. Nevertheless, despite this variability propolis may have a general pharmacological value, and this review systematically compiles, for the first time, the existing preclinical and clinical evidence of propolis activities as an antiviral and immunomodulatory agent, focusing on the possible application in respiratory diseases. In vitro and in vivo assays have demonstrated propolis broad-spectrum effects on viral infectivity and replication, as well as the modulatory actions on cytokine production and immune cell activation as part of both innate and adaptive immune responses. Clinical trials confirmed propolis undeniable potential as an effective therapeutic agent; however, the lack of rigorous randomized clinical trials in the context of respiratory diseases is tangible. Since propolis is available as a dietary supplement, possible use for the prevention of respiratory diseases and their deleterious inflammatory drawbacks on the respiratory tract in humans is considered and discussed. This review opens up new perspectives on the clinical investigation of neglected propolis biological properties which, now more than ever, are particularly relevant with respect to the recent outbreaks of pandemic respiratory infections.

The effects of phytochemicals and herbal bio-active compounds on tumour necrosis factor-α in overweight and obese individuals: a clinical review

Obesity is abnormal fat accumulation in the body which acts as a risk factor for various cardiometabolic states. Adipose tissue in excess can release inflammatory factors, including TNF-α and IL-6, and suppress adiponectin production. TNF-α increases the levels of IL-6 and acute phase reactants such as C-reactive protein. Inflammation has a crucial role in developing and progressing various cardiometabolic diseases and a wide range of obesity-related complications. It has been shown that TNF-α has a significant role in the development of insulin resistance. Recently, a growing body of evidence has focused on herbal medicine, phytochemicals and natural bioactive compounds as inexpensive, relatively easy accessible agents with low adverse effects to reduce inflammatory markers such as TNF-α and simultaneously decrease insulin resistance, glucose intolerance, and dyslipidemia in obesity. The main focus of the current review is to summarize the results of the studies, which assessed the effects of phytochemicals and herbal bio-active compounds on serum TNF-α in subjects with overweight or obesity. This review suggests that herbal medicine have favorable effects on the reduction of TNF-α concentration; however, the results were not uniform for different products. Among the reviewed plants, ginger, ginseng, resveratrol, and flaxseed had more promising effects.

Chemical toxicity assessment and Physiological investigation in rats exposed to pyrethroid insecticide type 1 and possible mitigation of propolis

The current investigation aims to study the potential protective effects of propolis methanolic extract (100 mg/kg BW) on the systemic toxic effects after dietary exposure concentration (1/100 LD50 for 30 days) of permethrin (PM) administered in experimental rats. In this experiment, we added propolis four weeks after PM -administration to examining the medicinal effects. Therapeutic use of propolis mitigated PM -induced deterioration of liver and kidney functions and myocardial damage measured by cardiac enzymes lactate dehydrogenase (LDH) and creatine kinase MB (CK-MB) in serum. In addition, propolis treatment (prophylactic and therapeutic) prevented PM-induced apoptosis index, including B-cell lymphoma protein 2 (BCL-2)-associated X (BAX) protein activates, and lipid peroxide (LP). The results showed propolis induced a significant decrease in serum levels of thyroid hormones (T3 and T4), proinflammatory cytokines tumor necrosis factor-alpha (TNF-α), interferon-gamma (INF-γ), interleukin one beta (IL-1β), interleukin 12 (IL-12), and interleukin 6 (IL-6). Besides, nuclear factor-kappa B (NF-kB), acetylcholine esterase (AChE), and hematological constituents. Cardiac biomarkers, liver, and kidney functions were substantially lower in propolis treatment. High-performance liquid chromatography (HPLC) and Gas chromatography–mass spectrometry (GC- MS) of the propolis-MeOH extract showed valuable antioxidant phenolics and flavonoids capable of alleviating oxidative stress through the free-radical scavenging efficacy and regulating signaling pathways of proinflammatory cytokines.

Can Propolis Be a Useful Adjuvant in Brain and Neurological Disorders and Injuries? A Systematic Scoping Review of the Latest Experimental Evidence

Propolis has been used therapeutically for centuries. In recent years, research has demonstrated its efficacy as a potential raw material for pharmaceuticals and nutraceuticals. The aim of the present scoping review is to examine the latest experimental evidence regarding the potential use of propolis in protecting the brain and treating neurological disorders and injuries. A systematic scoping review methodology was implemented. Identification of the research themes and knowledge gap was performed. After applying the exclusion criteria, a total of 66 research publications were identified and retrieved from Scopus, Web of Science, Pubmed, and Google Scholar. Several key themes where propolis is potentially useful were subsequently identified, namely detoxification, neuroinflammation, ischemia/ischemia-reperfusion injury/traumatic brain injury, Alzheimer's disease, Parkinson's disease, and epilepsy models, depression, cytotoxicity, cognitive improvement, regenerative medicine, brain infection, and adverse effects. In conclusion, propolis is shown to have protective and therapeutic benefits in alleviating symptoms of brain and neurological disorders and injuries, demonstrated by various in vitro studies, animal models, and human clinical trials. Further clinical research into this area is needed.

Propolis increases Foxp3 expression and lymphocyte proliferation in HIV-infected people: A randomized, double blind, parallel-group and placebo-controlled study

HIV infection and the prolonged use of antiretroviral therapy (ART) contribute to persistent inflammation and immune deregulation in people living with HIV/AIDS (PLWHA). Propolis is a bee product with plenty of biological properties, including immunomodulatory and anti-inflammatory action. This work aimed to evaluate possible changes in the immune/inflammatory response in PLWHA under ART after propolis intake. Asymptomatic PLWHA were double-blindly randomized into parallel groups receiving propolis (500 mg/day, n = 20) for 3 months or placebo (n = 20). Plasma cytokines (TNF-α, IL-2, IL-4, IL-6, IL-10 and IL17) were evaluated by cytometric bead array; cytokine production by PBMC (IFN-γ, IL-5, IL-17, IL-10, IL-1β, IL-18, and IL-33) was assessed by ELISA; gene expression (T-bet, GATA-3, RORγt and Foxp3) was determined by RT-qPCR, and cell proliferation was analysed by flow cytometry using CFSE staining. The average of gender, age, CD4⁺/CD8⁺ T cell count, time of diagnosis and treatment were similar in both groups. No differences were observed in cytokine levels nor in inflammasome activation. However, Pearson's correlation showed that IL-10 was directly correlated to CD4⁺ T cell count and inversely to IFN-γ after treatment with propolis. Foxp3 expression and lymphocyte proliferation increased in the propolis group. Data suggested that daily propolis consumption may improve the immune response and decrease the inflammatory status in asymptomatic PLWHA under ART.

Effect of propolis supplementation on athletic performance, body composition, inflammation, and oxidative stress following intense exercise: A triple-blind randomized clinical trial

BACKGROUND

Emerging evidence indicates that propolis as a novel potential antioxidant has unique benefits. This study aimed to evaluate the effect of propolis on oxidative stress, inflammation, body composition, and athletic performance in healthy active subjects.

METHODS

This clinical trial was conducted on 54 male military cadets. Eligible subjects were randomly allocated to receive a single dose of 450 mg propolis twice daily for four weeks or a matching placebo containing microcrystalline cellulose. Cooper 12-min run test and running-based anaerobic sprint test were performed to measure aerobic and anaerobic performance. Blood samples were obtained immediately after Cooper's test to evaluate oxidative stress and inflammation status. Fat mass and fat-free mass were analyzed using bioelectrical impedance.

RESULTS

Mean changes in fat mass, fat-free mass, anaerobic powers, fatigue index, and VO2 max did not differ significantly between the two groups after the adjustment for baseline values (P-value>0.05). A significant change was observed in plasma levels of IL-6 (-1.43 ± 0.11pg/mL), total oxidant status (-3.9 ± 0.2µmol/L), total antioxidant capacity (164 ± 12 µmol/L), malondialdehyde (-0.52 ± 0.03µmol/L), oxidative stress index (-0.45 ± 0.04), and glutathione (48.72±2µmol/L) in the propolis group compared with the placebo group after the adjustment for baseline values and weight changes (P-value<0.05). Although IL-10 concentrations had no significant changes in both groups, the ratio of IL-6/IL-10 significantly reduced in the propolis group compared with the placebo group (-0.174 ± 0.015 versus. 0.051 ± 0.014; P-value: 0.041).

CONCLUSIONS

Our results indicated that propolis might have beneficial effects on oxidative stress and inflammation following intense activities in healthy male subjects.

The effect of propolis supplementation on inflammatory factors and oxidative status in women with rheumatoid arthritis: Design and research protocol of a double-blind, randomized controlled

Backgrounds and aims

Rheumatoid arthritis (RA), is immune-inflammatory disease which is associated with great pain and disability. Overproduction of pro-inflammatory cytokines and oxidative stress play an important role in RA pathogenesis and related outcomes. The aim of this study was to evaluate the effects of propolis on inflammatory biomarkers and oxidative stress status in RA patients.

Methods/design

Randomized, placebo-controlled, and double-blind clinical trial aiming to recruit 48 patients with RA. Block randomization will be used. An intervention group will receive 500 mg/twice a day propolis capsules for 3 months and control group will receive the placebo for the same dose and duration. The oxidative stress status (malondialdehyde (MDA), total antioxidant capacity (TAC), total oxidant status (TOS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx)), and inflammatory biomarkers (interleukin-17 (IL-17), Tumor necrosis factor alpha (TNF-α), High-sensitivity C-reactive protein (hs-CRP)), lipid profile (total cholesterol (TC), high density lipoprotein (HDL-c), low density lipoprotein (LDL-c), and triglyceride (TG)) and also physical activity, anthropometric indices, clinical and nutritional status will be measured at beginning and end of this study. The primary analysis will be based on theintention-to-treat principle.

Discussion

If this randomized clinical trial shows the reduction in inflammatory cytokines and oxidative stress and improves clinical outcome, it would provide evidence for other clinical trials to evaluate the efficacy of propolis supplementation in RA patients.

Effects of propolis supplementation on glycemic status, lipid profiles, inflammation and oxidative stress, liver enzymes, and body weight: a systematic review and meta-analysis of randomized controlled clinical trials

The aim of meta-analysis was to assess the effects of propolis on markers of oxidative stress, lipid profiles, inflammation and glycemic control, liver enzymes, and weight control. The heterogeneity between the included studies was indicated using the Cochrane's Q test and I-square (I2) statistic. 14 trials were included in this meta-analysis. Our meta-analysis indicated a significant reduction in fating glucose (WMD: -17.00; 95% CI: -30.88, -3.11), HbA1C (WMD: -0.42; 95% CI: -0.75, -0.10), and insulin (WMD: -1.75; 95% CI: -3.24, -0.26) and a marginally significant reduction in insulin resistance (WMD: -0.60; 95% CI: -1.20, 0.00) following propolis supplementation in 10, 8, 6, and 5 studies, respectively. Pooling 5 effect sizes, a significant reduction was seen in ALT (WMD: -5.63; 95% CI: -10.59, -0.67) and aspartate aminotransferase (AST) (WMD: -3.09; 95% CI: -5.15, -1.03) following propolis. A significant beneficial effect was observed for CRP (WMD: -1.11; 95% CI: -1.92, -0.29), TNF-α (WMD: -6.71; 95% CI: -9.44, -3.98) and interleukin-6 (IL-6) (WMD: -17.99; 95% CI: -35.56, -0.42) concentrations after propolis supplementation. This study demonstrated the beneficial effects of propolis on FPG, HbA1c, insulin, CRP, TNF-α and liver enzymes levels.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40200-020-00696-w.

Propolis in Metabolic Syndrome and Its Associated Chronic Diseases: A Narrative Review

Propolis is a resinous product collected by bees from plants to protect and maintain the homeostasis of their hives. Propolis has been used therapeutically by humans for centuries. This review article attempts to analyze the potential use of propolis in metabolic syndrome (MetS) and its associated chronic diseases. MetS and its chronic diseases were shown to be involved in at least seven out of the top 10 causes of death in 2019. Patients with MetS are also at a heightened risk of severe morbidity and mortality in the present COVID-19 pandemic. Propolis with its antioxidant and anti-inflammatory properties is potentially useful in ameliorating the symptoms of MetS and its associated chronic diseases. The aim of this article is to provide a comprehensive review on propolis and its therapeutic benefit in MetS and its chronic diseases, with an emphasis on in vitro and in vivo studies, as well as human clinical trials. Moreover, the molecular and biochemical mechanisms of action of propolis are also discussed. Propolis inhibits the development and manifestation of MetS and its chronic diseases by inhibiting of the expression and interaction of advanced glycation end products (AGEs) and their receptors (RAGEs), inhibiting pro-inflammatory signaling cascades, and promoting the cellular antioxidant systems.

To bee or not to bee? The bee extract propolis as a bioactive compound in the burden of lifestyle diseases

Propolis is a polyphenolic plant resin collected by bees to protect hives against pathogens and temperature drop. It exhibits antibacterial, antioxidant, and antiinflammatory properties. Propolis has been reported to possess antidiabetic properties and display beneficial effects against cardiovascular disease, gut dysbiosis, and chronic kidney disease. It has an excellent clinical safety profile, with no known toxic effects described so far. In this review, we discuss the salutogenic effects of propolis, with particular reference to modulating notable features of chronic kidney disease, notably those involving cardiovascular risks.