PMID: 

Phytother Res. 2019 Jun ;33(6):1616-1626. Epub 2019 Apr 5. PMID: 30950136

Abstract Title: 

The efficacy of propolis on markers of glycemic control in adults with type 2 diabetes mellitus: A systematic review and meta-analysis.

Abstract: 

BACKGROUND AND OBJECTIVES: The impetus for the current study was to evaluate the efficacy of propolis supplementation on markers of glycemic status in adults with type 2 diabetes mellitus (T2DM).METHODS: A comprehensive search was conducted in PubMed, Scopus, Cochrane Library, Web of Science, and Google Scholar up to August 2018, identifying randomized controlled trials investigating the effect of propolis supplementation on glycemic markers in adults with T2DM. Cochrane Collaboration tool was used to evaluate the risk of bias assessment. A random-effects model was applied in the meta-analysis to compensate for potential heterogeneity among the included studies.RESULTS: Six randomized controlled trials comprising 373 participants were included in the systematic review and meta-analysis. The results of the meta-analysis revealed significant reductions in fasting plasma glucose (-13.51 mg/dl; 95% CI [-24.98, -2.04]) and hemoglobin A1C (-0.52%; 95% CI [-0.94, -0.10]) concentrations following propolis supplementation. However, no significant lowering effect was observed in fasting insulin levels (-0.53 pmol/L; 95% CI [-1.69, 0.63]) or homeostasis model assessment of insulin resistance (-0.543; 95% CI [-1.72, 0.64]).CONCLUSION: This systematic review and meta-analysis suggested that propolis supplementation may be effective in controlling glycemic levels for T2DM patients. Further studies are needed to confirm these results.

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PMID: 

Biofouling. 2019 03 ;35(3):308-319. Epub 2019 Apr 24. PMID: 31014106

Abstract Title: 

Brazilian red propolis reduces orange-complex periodontopathogens growing in multispecies biofilms.

Abstract: 

This study investigated the antimicrobial effects of the ethanolic extract of Brazilian red propolis (BRP) on multispecies biofilms. A seven-day-old subgingival biofilm with 32 species was grown in a Calgary device. Biofilms were treated with BRP (1,600, 800, 400 and 200 μg ml) twice a day for 1 min, starting from day 3. Chlorhexidine (0.12%) and dilution-vehicle were used as positive and negative controls, respectively. On day 7, metabolic activity and the microbial composition of the biofilms by DNA-DNA hybridization were determined. The viability data were analyzed by one-way ANOVA followed by Tukey's, whereas the microbial composition data were transformedBOX-COX and analyzed using Dunnett's. BRP (1,600 μg ml) decreased biofilm metabolic activity by 45%, with no significant difference from chlorhexidine-treated samples. BRP (1,600 μg ml) and chlorhexidine significantly reduced levels of 14 bacterial species compared to the vehicle control. Taken together, BRP showed promising antimicrobial properties which may be useful in periodontal disease control.

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PMID: 

Antioxidants (Basel). 2019 May 9 ;8(5). Epub 2019 May 9. PMID: 31075866

Abstract Title: 

Propolis Extracts Inhibit UV-Induced Photodamage in Human Experimental In Vitro Skin Models.

Abstract: 

The aim of this study was to assess the antioxidant, photoprotective, and antiaging effects of Greek propolis. Propolis was subjected to n-heptane or methanol extraction. Total phenolic/flavonoid content and antioxidant potential were determined in the extracts. Promising extracts were evaluated for their cytoprotective properties using human immortalized keratinocyte (HaCaT) or reconstituted human skin tissue following exposure to UVB. Assessment of cytotoxicity, DNA damage, oxidative status, and gene/protein expression levels of various matrix metalloproteinases (MMPs) were performed. The propolis methanolic fractions exhibited higher total phenolic and flavonoid contents and significant in vitro antioxidant activity. Incubation of HaCaT cells with certain methanolic extracts significantly decreased the formation of DNA strand breaks following exposure to UVB and attenuated UVB-induced decrease in cell viability. The extracts had no remarkable effect on the total antioxidant status, but significantly lowered total protein carbonyl content used as a marker for protein oxidation in HaCaT cells. MMP-1, -3, -7, and -9, monitored as endpoints of antiaging efficacy, were significantly reduced by propolis following UVB exposure in a model of reconstituted skin tissue. In conclusion, propolis protects against the oxidative and photodamaging effects of UVB and could be further explored as a promising agent for developing natural antiaging strategies.

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PMID: 

Nutr Cancer. 2019 Jul 18:1-21. Epub 2019 Jul 18. PMID: 31318622

Abstract Title: 

Propolis Potentiates Methotrexate Anticancer Mechanism and Reduces its Toxic Effects.

Abstract: 

Egyptian propolis is a powerful antioxidant and free radical scavenger produced by bees. The current study was designed to characterize Egyptian propolis, investigate its anticancer effect in vitro and its protective role against methotrexate (MTX) toxicity in Ehrlich ascites carcinoma (EAC) experimental model. Our results revealed a high content of total phenolics, flavonoids and dihydroflavonols in propolis ethanolic extract (PEE). PEE prompted cytotoxic effects in cancer cell lines and antitumor effects against EAC mice model by reducing tumor volume, count of viable tumor cells with a significant elevation in the life span as well as the mean survival time of mice. The hepatic and renal biochemical and toxicity parameters of EAC-bearing mice treated with MTX were improved by PEE. Also, it elevates the expression of Bax, caspase-3 and cytochrome-C and reduces the Bclexpression in EAC cells. Moreover, PEE with MTX induced cell cycle arrest at the G0/G1 phase. Interestingly, the combination of PEE with MTX showed potent apoptosis as shown by DNA fragmentation gel, comet assay and dihydrofolate reductase level (DHFR). These findings demonstrate that Egyptian propolis extract had high chemical diversity and different antioxidant effects. Also, it optimizes the antitumor potential of MTX and declined its toxic effects.

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PMID: 

Cell Physiol Biochem. 2019 ;53(2):301-322. PMID: 31343125

Abstract Title: 

The Therapeutic Mechanisms of Propolis Against CCl-Mediated Liver Injury by Mediating Apoptosis of Activated Hepatic Stellate Cells and Improving the Hepatic Architecture through PI3K/AKT/mTOR, TGF-β/Smad2, Bcl2/BAX/P53 and iNOS Signaling Pathways.

Abstract: 

BACKGROUND/AIMS: Propolis is one of the most promising natural products, exhibiting not only therapeutic but also prophylactic actions. Propolis has several biological and pharmacological properties, including hepatoprotective activities. The present study aimed to investigate the underlying molecular mechanisms of propolis against CCl-mediated liver fibrosis.METHODS: Three groups of male BALB/c mice (n=15/ group) were used: group 1 comprised control mice; groups 2 and 3 were injected with CClfor the induction of liver fibrosis. Group 3 was then orally supplemented with propolis (100 mg/kg body weight) for four weeks. Different techniques were used to monitor the antifibrotic effects of propolis, including histopathological investigations using H&E, Masson's trichrome and Sirius red staining; Western blotting; flow cytometry; and ELISA.RESULTS: We found that the induction of liver fibrosis by CClwas associated with a significant increase in hepatic collagen andα-smooth muscle actin (α-SMA) expression. Moreover, CCl-treated mice also exhibited histopathological alterations in the liver architecture. Additionally, the liver of CCl-treated mice exhibited a marked increase in proinflammatory signals, such as increased expression of HSP70 and increased levels of proinflammatory cytokines and ROS. Mechanistically, the liver of CCl-treated mice exhibited a significant increase in the phosphorylation of AKT and mTOR; upregulation of the expression of BAX and cytochrome C; downregulation of the expression of Bcl2; a significant elevation in the levels of TGF-β followed by increased phosphorylation of SMAD2; and a marked increase in the expression of P53 and iNOS. Interestingly, oral supplementation of CCl-treated mice with propolis significantly abolished hepatic collagen deposition, abrogated inflammatory signals and oxidative stress, restored CCl-mediated alterations in the signaling cascades, and hence repaired the hepatic architecture nearly to the normal architecture observed in the control mice.CONCLUSION: Our findings revealed the therapeutic potential and the underlying mechanisms of propolis against liver fibrosis.

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PMID: 

J Food Biochem. 2019 Aug ;43(8):e12926. Epub 2019 Jun 10. PMID: 31368546

Abstract Title: 

Propolis attenuates lipopolysaccharide-induced inflammatory responses through intracellular ROS and NO levels along with downregulation of IL-1β and IL-6 expressions in murine RAW 264.7 macrophages.

Abstract: 

Propolis had a wide spectrum of biological activities. In the current study, antioxidative and the immunomodulatory effects of the Polur ethanol extract of propolis (PEEP) in murine macrophage (RAW 264.7) cells were investigated. Bioactive composition of the PEEP was determined by HPLC analysis. Cells were treated with different concentrations of PEEP and LPS, then cell viability, NO levels, and expression of inflammatory factors were evaluated. HPLC analysis of PEEP indicated the presence of flavonoids and phenolic acid. The PEEP inhibited the proliferation of RAW 264.7 cells with IC15± 3.2 µg/ml. Reactive oxygen species (ROS) and NO production was significantly reduced by 0.15 µg/ml of PEEP. Additionally, expression of Cox-2, IL-1β and IL-6 significantly decreased. The obtained results supported the PEEP anti-inflammatory effects on RAW 264.7 cells may be applied via reducing ROS and NO production along with COX-2, IL-1β, and IL-6 expression. PRACTICAL APPLICATIONS: Propolis is a resinous substance produced by the honeybee that has been adopted as a form of traditional medicine since ancient times. The main compounds found in propolis are typically various and dependon the type of plants and climatic region. In this respect, a wide spectrum of biological activities for propolis has been identified including antioxidant, antimicrobial, anticarcinogenic, anti-inflammatory, as well as antifungal properties. This extraordinary substance is rich in flavonoids and antioxidants. Therefore, it is now widely used in foods and drinks with the claim that it can maintain or improve human health.

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PMID: 

Food Chem Toxicol. 2019 Aug ;130:99-108. Epub 2019 May 18. PMID: 31112706

Abstract Title: 

Detoxification effects of aloe polysaccharide and propolis on the urinary excretion of metabolites in smokers.

Abstract: 

The aim of the present study was to investigate the detoxifying effects of aloe polysaccharide (APS), propolis, and the mixture of APS and propolis on the urinary excretion of major human tobacco carcinogens, BaP and an addictive stimulant alkaloid, nicotine. Smokers (≥20 cigarettes/day) were randomly classified into four subgroups (10 people/group) and were given 600 mg/day of APS, 600 mg/day of propolis, or 600 mg/day of the mixture of APS (420 mg/day) and propolis (180 mg/day) for four weeks. Urinary excretion of BaP and cotinine (a metabolite of nicotine) increased in a time-dependent manner increased after supplementation with APS (BaP, 2.23-fold; cotinine, 2.64-fold), propolis (BaP, 1.30-fold; cotinine, 2.08-fold), and the mixture (BaP, 2.33-fold; cotinine, 2.28-fold) compared with smoker control. Creatinine, glucose, and total bilirubin levels significantly decreased in a time-dependent manner after supplementation with APS (creatinine, 15.24%; glucose, 40.22%; total bilirubin, 48.82%), propolis (creatinine, 16.83%; glucose, 36.25%; total bilirubin, 52.59%), and the mixture (creatinine, 16.36%; glucose, 46.37%; total bilirubin, 39.20%) (p 

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PMID: 

Pharmacol Res. 2019 Aug ;146:104315. Epub 2019 Jun 14. PMID: 31207343

Abstract Title: 

Aloe-emodin attenuates myocardial infarction and apoptosis via up-regulating miR-133 expression.

Abstract: 

Aloe-emodin (AE) is an anthraquinone derived from rhubarb and has a variety of pharmacological actions. However, the role of AE in regulating ischemic heart diseases is still unclear. The present study investigated the effect of AE on cardiac injuries induced by myocardial infarction (MI) in vivo and oxidative insults in vitro and explored the mechanisms involved. TUNEL and Flow cytometry were performed to measure cell apoptosis. Western blot analysis was employed to detect expression of Bcl-2, Bax and Caspase-3 proteins. Real-time PCR was used to quantify the microRNAs levels. Our data showed that AE protected neonatal rat ventricular myocytes (NRVMs) from hydrogen peroxide (HO) induced apoptosis and significantly inhibited HO-induced reactive oxygen species (ROS) elevation. Furthermore, AE treatment significantly reversed HO-induced upregulation of Bax/Bcl-2 and the loss of mitochondrial membrane potential. In vivo, AE treatment significantly reduced infarct size, ameliorated impaired cardiac function and obviously decreased cardiac apoptosis and oxidative stress in MI mice heart. Meanwhile, AE restored HO-induced downregulation of miR-133, and transfection with miR-133 inhibitor abolished the anti-apoptotic and anti-oxidative effects of AE. Moreover, AE prevented HO-induced increase in caspase-3 activity, which was diminished by application of miR-133 inhibitor. Our results indicate that AE protectes against myocardial infarction via the upregulation of miR-133, inhibition of ROS production and suppression of caspase-3 apoptotic signaling pathway.

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PMID: 

Mymensingh Med J. 2019 Jul ;28(3):490-496. PMID: 31391416

Abstract Title: 

Antibacterial Effect of Aloe vera (Aloe barbadensis) leaf gel against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae.

Abstract: 

This experimental study was carried out to determine the antibacterial effect of Ethanolic extract of Aloe vera leaf gel (EAE) against standard strains of Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae in the Department of Pharmacology&Therapeutics in collaboration with the Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh from July 2017 to June 2018. Ethanol extract was used in five different concentrations (100, 200, 300, 400 and 500μg/ml). Dose dependent inhibitory effect was seen against the test organisms using disc diffusion method. For S. aureus, Zones of inhibition (ZOI) were 7, 12, 13, 16 and 20 mm at 100, 200, 300, 400 and 500 μg/ml respectively; for P. aeruginosa, ZOI were 0, 7, 12, 14 and 17 mm at 100, 200, 300, 400and 500 μg/ml respectively; for E. coli, ZOI were 0, 8, 12, 15 and 18 mm at 100, 200, 300, 400 and 500 μg/ml respectively; for K. pneumoniae, ZOI were 7, 10, 11, 13 and 17 mm at 100, 200, 300, 400 and 500 μg/ml respectively. The minimum inhibitory concentration (MIC) was assessed by broth dilution technique. The MICs of EAE for S. aureus, P. aeruginosa, E. coli and K. pneumoniae were 500, 650, 650 and 600 μg/ml respectively. From the study it is clearly observed that ethanolic extract of Aloe vera leaf gel possesses antibacterial effect against the test pathogens. Further studies are required to detect and isolate the biologically active ingredients present in the Aloe vera leaves which are responsible for this antibacterial effect. Hopefully, that would lead to the discovery of new and more potent antimicrobial agents originated from Aloe vera.

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PMID: 

Evid Based Complement Alternat Med. 2019 ;2019:2951428. Epub 2019 Jul 17. PMID: 31391857

Abstract Title: 

Dandelion Root and Lemongrass Extracts Induce Apoptosis, Enhance Chemotherapeutic Efficacy, and Reduce Tumour Xenograft Growthin Prostate Cancer.

Abstract: 

Many conventional chemotherapies have indicated side effects due to a lack of treatment specificity and are thus not suitable for long-term usage. Natural health products are well-tolerated and safe for consumption, and some have pharmaceutical uses particularly for their anticancer effects. We have previously reported the anticancer efficacy of dandelion () root and lemongrass () extracts. However, their efficacy on prostate cancer and their interactions with standard chemotherapeutics have not been studied to determine if they will be suitable for adjuvant therapies. If successful, these extracts could potentially be used in conjunction with chemotherapeutics to minimize the risk of drug-related toxicity and enhance the efficacy of the treatment. We have demonstrated that both dandelion root extract (DRE) and lemongrass extract (LGE) exhibit selective anticancer activity. Importantly, DRE and LGE addition to the chemotherapeutics taxol and mitoxantrone was determined to enhance the induction of apoptosis when compared to individual chemotherapy treatment alone. Further, DRE and LGE were able to significantly reduce the tumour burden in prostate cancer xenograft models when administered orally, while also being well-tolerated. Thus, the implementation of these well-tolerated extracts in adjuvant therapies could be a selective and efficacious approach to prostate cancer treatment.

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