Propolis
VIDEOS:
What is Propolis?
Qualities Warming, drying
Properties Antibacterial, antifungal, expectorant, immune amphoteric
Propolis is extensively used in foods and beverages because it improves human health. It contains more than 300 natural compounds such as polyphenols, phenolic aldehydes, sequiterpene-quinones, coumarins, amino acids, steroids and inorganic compounds. Propolis exhibits a broad spectrum of biological and pharmacological properties such as antimicrobial, antioxidant, anti-inflammatory, immunomodulatory, antitumor, anticancer, antiulcer, hepatoprotective, cardioprotective, and neuroprotective actions. The chemical composition and beneficial properties of propolis vary greatly depending on the phytogeographical areas, seasonal collection time, and botanical source. Polyphenols found in fruits and vegetables are beginning to receive increased attention due to their vital role in protecting neural cells from oxidative stress and neuroinflammation associated with normal aging and chronic age-related diseases. Propolis is one of the most abundant sources of polyphenols (mainly flavonoids and phenolic acids).
Its good for the tracheal cough where the vocal chords are affected.
H. Pylori
Propolis has demonstrated excellent ability to reduce the urease activity of H Pylori; this was linked with the polyphenol content of the propolis. While this itself is unlikely to eradicate the organism, it may reduce the way that H Pylori can mess with the acidity of the gut (and lead to SIBO and further complications at the gall bladder, etc) and cause insomnia (as the ammonia produced by this enzyme is a strong agitating factor in the central nervous system). Most of the studies on propolis have been in vitro studies, which gives us little idea of how effective its usage will be in humans, although one human study demonstrated that propolis improved the eradication rate when added to standard protocols. When used as a stand-alone, only 2/18 (11%) had eradicated the bacteria after 40 days of treatment.
Propolis inhibits more than just urease, and has also been shown to inhibit xanthine oxidase and acetylcholinesterase, meaning that is may have an impact in gout and brain sharpness respectively.
Summary: proven ability to limit H Pylori-related complications and the bug’s own defence strategies against gastric acid, proven ability to enhance standard treatment but eradication of H Pylori is possible-but-still-unlikely when used alone.
It shows a very similar mechanism to Mastic Gum. And, like Mastic, it is well-tolerated and reliably provides symptomatic relief (even if this rarely sees direct eradication) but its urease inhibition makes it particularly valuable.
Uses
Cancer
Laboratory studies show that propolis has anticancer properties. One study on propolis supplementation for colon cancer prevention in high risk patients found no benefit, and actually indicated potential negative effects on muscle tissues including heart muscle cells.
Cancer treatment-related oral ulcerations (mucositis)
A few studies evaluating propolis-containing products have had mixed results. Additional studies are needed.
Diabetes
There is no scientific evidence to support this use.
Heart disease
This claim is not backed by clinical data.
Infections
A few small studies suggest that propolis can be effective in treating ear infections. Larger studies are needed.
Inflammation
Laboratory studies show that propolis has immunomodulatory effects. Human studies are needed.
Clinical Summary
Propolis is a resinous mixture of pollen and beeswax collected by honeybees from the buds and exudates of certain trees and plants . It has been used in folk medicine and in food and beverages to improve health and prevent disease. Propolis is thought to have antibacterial, antiviral, antifungal, antiinflammatory, antioxidant, immunostimulatory, antiproliferative, vasomodulatory, cardioprotective, and radioprotective properties .
In vitro studies demonstrate synergistic antimicrobial effects when propolis is used with honey or ethyl alcohol . Propolis also enhanced the antitumor effects of temozolomide in human glioblastoma cell lines . Another study found propolis to have greater cytotoxic activity against human lung adenocarcinoma and fibrosarcoma cells compared with 5-fluorouracil . Propolis and several of its constituents demonstrated anticancer activities in several human cancer cell lines.
In animal models, propolis and its constituents have demonstrated cardiovascular , wound-healing , and antitumor activities .
Despite the number of laboratory studies, very few clinical trials of propolis have been conducted. Topical propolis extract may be helpful in treat fungal foot infections, but confirmatory studies are needed . A pilot study suggests ethanolic propolis extract reduces microbial count and improves symptoms from periodontal treatment . Clinical data also show propolis to be an effective adjuvant treatment for asthma , and to treat plane and common warts . A propolis/zinc suspension reduced the number of acute otitis media infections in children.
Only a few trials evaluate propolis for cancer and treatment-related mucositis. In a pilot randomized placebo-controlled double-blind study, supplemental propolis was not effective for colon cancer prevention and suggested negative effects on muscle tissues including myocardial cells . The effects of propolis on chemotherapy-induced mucositis are thus far equivocal with results from only two small double-blind controlled trials: one in adults with grade 2/3 mucositis found benefits with both the topical application of honey and a proprietary mixture of honey, olive oil-propolis extract, and beeswax compared with controls , but another in pediatric patients with severe mucositis self administering topical propolis alone did not find benefit . An open-label study evaluating a mucoadhesive propolis gel for mucositis did find benefit, but confirmatory studies are needed.
Bee pollen, a constituent of propolis, is a mixture of plant pollens, nectar, and bee saliva that bees form into granules to store as food. It is claimed as a “cure all” by some and is touted for its antiaging and stamina-increasing properties, antioxidant effects, and for chronic prostatitis, among other conditions. Aside from its nutritional value, clinical data show that bee pollen has limited benefits in improving athletic performance.
The use of propolis and bee pollen is relatively benign. However, hypersensitivity reactions to each of these supplements have been reported.
In addition, although a number of laboratory studies indicate anticancer effects, propolis or its constituents may also act as pro-oxidants , produce cytotoxic effects in normal cells , and/or have mutagenic activity under certain circumstances indicating that risk versus benefit also needs further evaluation.
Mechanism of Action
In vitro studies have identified a number of active propolis constituents and their potential mechanisms. Generally, antimicrobial and antioxidant activities are related to total phenolic contents ; caffeic acid phenethyl ester (CAPE) and artepillin C are well-known anti-inflammatory components ; and the main active anticancer constituents are CAPE and chrysin . However, all of these constituents also possess these other characteristics to some degree and vary with geographic origin.
CAPE specifically inhibits nuclear factor-kappaB (NF-kB) . In human breast cancer cells, it also inhibits MDR gene expression, epidermal growth factor receptor (EGFR), and vascular endothelial growth factor (VEGF) . CAPE decreased malignancy potential of breast cancer stem cells via inhibition of self-renewal, progenitor formation, and clonal growth, and significantly decreased CD44 expression . CAPE-initiated S- and G2/M-phase cell-cycle
arrests and apoptosis in human cervical cancer lines was associated with increased E2F-1 expression.
The flavonoid chrysin demonstrated photoprotective effects by attenuating UVA- and UVB-induced apoptosis, reactive oxygen species (ROS) production, and cyclooxygenase 2 (COX-2) expression . Chrysin is an inhibitor of aromatase, an enzyme converting testosterone into estrogen . It is also a histone deacetylase (HDAC) inhibitor and inhibited HDAC8 enzymatic activity and tumor growth in human breast cancer cell lines . Chrysin may overcome tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) resistance through Mcl-1 downregulation via STAT3 phosphorylation inhibition . A novel chrysin-organogermanium complex demonstrated inhibitory effects across several human cancer cell lines, with high selectivity between cancer cells and normal cells causing membrane toxicity as demonstrated by decreased cell rigidity and adhesion force, and apoptosis via ROS-dependent mitochondrial pathways.
The phenolic compound artepillin C is the major constituent that stimulates pungent taste by activating TRPA1 channels . Its immune-modulating effects are attributed to suppression of interleukin (IL)-2, interferon (IFN)-gamma and IL-17 expression in alloreactive CD4 T cells, suggesting its potential in treating graft versus host disease . Artepillin C also sensitizes prostate cancer cells to TRAIL-induced apoptosis by engaging both extrinsic receptor-mediated and intrinsic mitochondrial apoptotic pathways . In different tumor cell lines, artepillin C and baccharin were found to be more cytotoxic than propolis, without additive or synergistic effects when combined.
Induction and/or inhibition of hypoxia-inducible factor-1alpha (HIF-1) and HIF-1 target genes also been demonstrated with other constituents, including polyphenols, cinnamic acid derivatives baccharin and drupanin, and the flavonoids beturetol and isosakuranetin . Baccharin plus drupanin particularly exerted synergistic growth-inhibitory effects, via intrinsic and extrinsic apoptotic signaling transduction and by modulating miRNA expression . Baccharin demonstrates highly selective inhibition of human aldo-keto reductase superfamily (AKR1C3), and suppressed proliferation of PC3 prostate cancer cells stimulated by AKR1C3 overexpression . A synthesized baccharin derivative also demonstrated AKR1C3 inhibition.
Several compounds mostly belonging to the polycyclic polyprenylated acylphloroglucinols class demonstrated selective targeting of chemotherapy refractory neuroblastoma cancer stem cells by acting in a pleiotropic manner, including strong disruption of tubulin polymerization and inhibition of replicative enzymes like toposimerases I/II and DNA polymerase.
In vitro studies of propolis as a whole demonstrate significant free-radical scavenging activity and anti-inflammatory effects by modulating key inflammatory mediators of mRNA transcription, inhibiting specific inflammatory cytokines, and blocking NF-kB activation . Propolis was also found to inhibit proliferation and induce apoptosis in human leukemia cells through activation of caspase-3 via the mitochondrial pathway . Apoptotic induction in human breast cancer cells occurs partly through endoplasmic reticulum stress-related signaling , and synergy between propolis and temozolomide in human glioblastoma cell lines is also partly attributed to reduced NF-kB activity.
In animal models, an ethanolic propolis extract may enhance reverse cholesterol transport via stimulated plasma HDL levels and hepatic ABCA1 and ABCG1 expression . Propolis promotes wound-healing by exerting effects on mast cells that result in down regulation of type I allergy and inflammation and modifying fibronectin metabolism . Immunomodulatory effects occurred through increased toll-like receptor expression and IL-1beta and IL-6
production . Pretreatment with orally-administered propolis extract reduced doxorubicin-induced oxidative damage to heart mitochondria . Diabetic hepatorenal damage was attenuated via antioxidant activity including free radical scavenging, and was more pronounced in ethanol than water extracts . In human colon cancer models, oral propolis at doses that caused no detectable toxicity was associated with a decrease in mitotic cells and Ki-67 expression as well as increased endo-reduplications and p53 expression, and apoptosis in leukemia cells was associated with down regulation of Bcl-2 and Bax activation.