Review of the anticancer activities of bee products

Bee products have long been used in traditional medicine. The raw materials, crude extracts and purified active compounds from them have been found to exhibit interesting bioactivities, such as antimicrobial, anti-inflammatory and antioxidant activities. In addition, they have been widely used in the treatment of many immune-related diseases, as well as in recent times in the treatment of tumors. Bee product peptides induce apoptotic cell death in vitro in several transformed (cancer) human cell lines, including those derived from renal, lung, liver, prostate, bladder and lymphoid cancers. These bioactive natural products may, therefore, prove to be useful as part of a novel targeted therapy for some types of cancer, such as prostate and breast cancer. This review summarizes the current knowledge regarding the in vivo and in vitro potential of selective bee products against tumor cells.

Asian Pacific Journal Trop Biomed. (2014). Review of the anticancer activities of bee products. 4(5): 337-344.

Effects of Stingless Bee Propolis on Experimental Asthma

Bee products have been used empirically for centuries, especially for the treatment of respiratory diseases. The present study evaluated the effect of treatment with a propolis hydroalcoholic extract (PHE) produced by Scaptotrigona aff. postica stingless bee in a murine asthma model. BALB/c mice were immunized twice with ovalbumin (OVA) subcutaneously. After 14 days, they were intranasally challenged with OVA. Groups P50 and P200 received PHE by gavage at doses of 50 and 200 mg/kg, respectively. The DEXA group was treated with intraperitoneal injection of dexamethasone. The OVA group received only water. The mice were treated daily for two weeks and then they were immunized a second time with intranasal OVA. The treatment with PHE decreased the cell number in the bronchoalveolar fluid (BAL). Histological analysis showed reduced peribronchovascular inflammation after treatment with PHE especially the infiltration of polymorphonuclear cells. In addition, the concentration of interferon-γ (IFN-γ) in the serum was decreased. These results were similar to those obtained with dexamethasone. Treatment with S. aff postica propolis reduced the pathology associated with murine asthma due an inhibition of inflammatory cells migration to the alveolar space and the systemic progression of the allergic inflammation.

Hidelbland, J., Reis, A. S., Araujo, R., et. al. (2014). Effects of Stingless Bee Propolis on Experimental Asthma. Evidence Based Complement Alternative Medicine. 

Blueberry Supplementation Improves Memory in Older Adults

The prevalence of dementia is increasing with expansion of the older adult population.

In the absence of effective therapy, preventive approaches are essential to address this public health problem. Blueberries contain polyphenolic compounds, most prominently anthocyanins, which have antioxidant and anti-inflammatory effects. In addition, anthocyanins have been associated with increased neuronal signaling in brain centers mediating memory function as well as improved glucose disposal, benefits that would be expected to mitigate neurodegeneration.

We investigated the effects of daily consumption of wild blueberry juice in a sample of nine older adults with early memory changes. At 12 weeks, we observed improved paired associate learning (p = 0.009) and word list recall (p = 0.04). In addition, there were trends suggesting reduced depressive symptoms (p = 0.08) and lower glucose levels (p = 0.10). We also compared the memory performances of the blueberry subjects with a demographically-matched sample who consumed a berry placebo beverage in a companion trial of identical design and observed comparable results for paired associate learning.

The findings of this preliminary study suggest that moderate-term blueberry supplementation can confer neurocognitive benefit and establish a basis for more comprehensive human trials to study preventive potential and neuronal mechanisms.

Krikorian, R., Shidler, D. M., Nash, A. T., et al. (2010). Blueberry Supplementation Improves Memory in Older Adults. J Agric Food Chem. 58 (7): 3996-4000.

 

 

Recent trends and important developments in propolis research

Bees have been in existence for >125 million years and their evolutionary success has allowed them to become perennial species that can exploit virtually all habitats on Earth. This success is largely because of the chemistry and application of the specific products that bees manufacture: honey, beeswax, venom, propolis, pollen and royal jelly. As the most important ‘chemical weapon’ of bees against pathogenic microorganisms, propolis has been used as a remedy by humans since ancient times. It is still one of the most frequently used remedies in the Balkan states (1), applied for treatment of wounds and burns, sore throat, stomach ulcer, etc.

For this reason, propolis has become the subject of intense pharmacological and chemical studies for the last 30 years. As a result, much useful knowledge has been gathered. However, it is important to note that in the last decade, the paradigm concerning propolis chemistry radically changed. In the 1960s, propolis was thought to be of very complex, but more or less constant chemistry, like beeswax or bee venom (2,3). In the following years, analysis of numerous samples from different geographic regions led to the disclosure that the chemical composition of bee glue is highly variable. This circumstance was soon understood by seasoned chemists, such as Popravko (4) and Ghisalberti (5). Nevertheless, most of the scientists studying the biological properties of propolis continued to assume that the term ‘propolis’ was as determinative with respect to chemical composition as the botanical name for a medicinal plant. Numerous studies, carried out with the combined efforts of phytochemists and pharmacologists, led in recent years to the idea that different propolis samples could be completely different in their chemistry and biological activity.

To understand what causes the differences in chemical composition, it is necessary to keep in mind the plant origin of propolis. For propolis production, bees use materials resulting from a variety of botanical processes in different parts of plants. These are substances actively secreted by plants as well as substances exuded from wounds in plants: lipophilic materials on leaves and leaf buds, gums, resins, latices, etc. (6). The plant origin of propolis determines its chemical diversity. Bee glue's chemical composition depends on the specificity of the local flora at the site of collection and thus on the geographic and climatic characteristics of this site. This fact results in the striking diversity of propolis chemical composition, especially of propolis originating from tropical regions.

Nowadays, it is well documented that in the temperate zone all over the world, the main source of bee glue is the resinous exudate of the buds of poplar trees, mainly the black poplar Populus nigra (7). For this reason, European propolis contains the typical ‘poplar bud’ phenolics: flavonoid aglycones (flavones and flavanones), phenolic acids and their esters (8). Poplar trees are common only in the temperate zone; they cannot grow in tropical and subtropical regions. For this reason, in these habitats, bees have to find other plant sources of propolis to replace their beloved poplar. As a result, propolis from tropical regions has a different chemical composition from that of poplar type propolis. In the last decade, Brazilian propolis attracted both commercial and scientific interest. The main source of Brazilian bee glue turned out to be the leaf resin of Baccharis dracunculifolia (9,10). Among the main compound classes found in Brazilian propolis are prenylated derivatives of p-coumaric acid and of acetophenone. Diterpenes, lignans and flavonoids (different from those in ‘poplar type’ propolis) have also been found (9). However, in Brazil, several types of propolis were registered in recent studies (11,12), that come from plant sources different from B.dracunculifolia and containing compounds other than those mentioned above. Recently the chemistry of Cuban propolis caught the attention of scientists. Its main components are polyisoprenylated benzophenones, and this makes Cuban propolis different from both European and Brazilian bee glue. The plant source of this propolis type was detected to be the floral resin of Clusia rosea, from whence came the prenylated benzophenones (13). There is no doubt that in other ecosystems, propolis plant sources and the chemical composition of propolis will continue to surprise scientists.

The distinct chemistry of propolis from different origins leads to the expectation that the biological properties of different propolis types will be dissimilar. However, in most cases. this is not true! Actually, propolis is the defense of bees against infections, and the antibacterial and antifungal activity of all samples is not surprising.

Bankova, V. (2005). Recent trends and important developments in propolis research. Alternative Medicine. 2(1): 29-32.

Researcher proves seal oil far more beneficial than fish oil

An associate professor with the Department of Biochemistry has a tip for anyone taking fish oil supplements – switch to seal oil instead.

Dr. Sukhinder Kaur Cheema has spent seven years researching the benefits of fish oil on a species of hamster that is prone to atherosclerosis, a common arterial disease in which raised areas of degeneration and cholesterol deposits plaques form on the inner surfaces of the arteries obstructing blood flow. The hamster is a good model for such research because its lipid and cholesterol factors and metabolism are very similar to that of humans.

She found that past studies into the benefits of fish oil in human population have been varied, with some showing positive effects, such as a reduction in triglyceride levels, and others showing negative results, like an increase in plasma cholesterol levels. Most of the animal studies to investigate the mechanisms of action of fish oil have been conducted using mice and rats as an animal model. Dr. Cheema wanted to see what would happen if similar studies were done using hamsters.

“We took that particular hamster and fed them different amounts of fish oil in their diet, from low to high amounts,” she said. “It was really shocking for us to see that when we gave them a high fat fish oil diet the hamster’s blood turned very thick and milky. I thought my student had made a mistake, but further research showed this hamster had a problem processing fat.”

Dr. Cheema discovered that this hamster model had a very low activity level of a particular enzyme that helps people and animals digest and absorb fat and while it could digest other fats, fish oil fat was proving to be more than it could handle.

The health benefits of fish oil are due to the presence of long chain omega-3 polyunsaturated fatty acids. Seal oil, like fish oil, is also a rich source of omega-3 polyunsaturated fatty acids. However, seal oil contains high amounts of another omega-3 fatty acid that is low in fish oil. It is high in mono unsaturated fat, a “good” fat, while fish oil contains a lot of saturated fat, a
“bad” fat.

“So seal oil is already looking better than fish oil,” said Dr. Cheema. “We repeated the exact study to see if the alternate oil would make a difference and after four weeks of feeding seal oil to our hamsters we saw that they had no trouble digesting and absorbing it, compared to the fish oil.

“The enzyme that is low in this particular hamster is also deficient in some people in the human population,” she added. “So we believe people who already have a problem digesting and absorbing fat will likely not benefit from taking fish oil but may benefit from taking seal oil instead.”

The professor is currently looking into the possibility of beginning a clinical trial to test this theory on humans. She has presented her research at a number of conferences to overwhelming positive response.