533 research outputs found
Green Brazilian Propolis Action on Macrophages and Lymphoid Organs of Chronically Stressed Mice
Stress is a generic term that summarizes how psychosocial and environmental factors influence physical and mental well-being. The interaction between stress and immunity has been widely investigated, involving the neuroendocrine system and several organs. Assays using natural products in stress models deserve further investigation. Propolis immunomodulatory action has been mentioned and it has been the subject of scientific investigation in our laboratory. The aim of this study was to evaluate if and how propolis activated macrophages in BALB/c mice submitted to immobilization stress, as well as the histopathological analysis of the thymus, bone marrow, spleen and adrenal glands. Stressed mice showed a higher hydrogen peroxide (H2O2) generation by peritoneal macrophages, and propolis treatment potentiated H2O2 generation and inhibited nitric oxide (NO) production by these cells. Histopathological analysis showed no alterations in the thymus, bone marrow and adrenal glands, but increased germinal centers in the spleen. Propolis treatment counteracted the alterations found in the spleen of stressed mice. New research is being carried out in order to elucidate propolis immunomodulatory action during stress
The isolation of antiprotozoal compounds from Libyan propolis
Propolis is increasingly being explored as a source of biologically active compounds. Until now, there has been no study of Libyan propolis. Two samples were collected in North East Libya and tested for their activity against Trypanosoma brucei. Extracts from both samples had quite high activity. One of the samples was fractionated and yielded a number of active fractions. Three of the active fractions contained single compounds, which were found to be 13-epitorulosal, acetyl-13-epi-cupressic acid and 13-epi-cupressic acid, which have been described before in Mediterranean propolis. Two of the compounds had a minimum inhibitory concentration value of 1.56 µg/mL against T. brucei. The active fractions were also tested against macrophages infected with Leishmania donovani, and again moderate to strong activity was observed with the compounds having IC50 values in the range 5.1-21.9 µg/mL
In vitro evaluation of portuguese propolis and floral sources for antiprotozoal, antibacterial and antifungal activity
Propolis is a beehive product with a very complex chemical composition, used since ancient times in several therapeutic treatments. As a contribution to the improvement of drugs against several tropical diseases caused by protozoa, we screened Portuguese propolis and its potential floral sources Populus x Canadensis and Cistus ladanifer against Plasmodium falciparum, Leishmania infantum, Trypanosoma brucei and Trypanosoma cruzi. The toxicity against MRC-5 fibroblast cells was evaluated to assess selectivity. The in vitro assays were performed following the recommendations of WHO Special Programme for Research and Training in Tropical Diseases (TDR) and revealed moderate activity, with the propolis extracts presenting the relatively highest inhibitory effect against T. brucei. Additionally, the antimicrobial activity against Staphylococcus aureus, Candida albicans, Trichophyton rubrum and Aspergillus fumigatus was also verified with the better results observed against T. rubrum. The quality of the extracts was controlled by evaluating the phenolic content and antioxidant activity. The observed biological activity variations are associated with the variable chemical composition of the propolis and the potential floral sources under study.Soraia I. Falcão thanks FCT for the PhD grant SFRH/BD/44855/2008.
N. Vale thanks FCT for the Post-Doc grant SFRH/BPD/48345/2008.
Thanks also to FCT for financial support provided to CIMO (PEst-OE/
AGR/UI0690/2011) and CIQ-UP (PEst-C/QUI/UI0081/2011). Thanks
are due to the National Federation of Portuguese Beekeepers, for
supplying propolis samples.info:eu-repo/semantics/publishedVersio
Antitumoral and antiangiogenic activity of Portuguese propolis in in vitro and in vivo models
Propolis, a natural product, has important biological properties, however, studies with Portuguese propolis are scarce. Thus, we aimed to characterize the chemical composition and the antitumoural and antiangiogenic activities of a sample from Pereiro (Portugal). The chemical profile of our propolis sample (P10.EE) is similar to the poplar propolis type. P10.EE decreased cell viability of different tumour cells, being less cytotoxic against non-tumoural cells. P10.EE decreased MDA-MB-231 and DU145 cell proliferation and migration, with cell cycle changes and increased cell death. The increased glucose consumption and lactate production in MDA-MB-231 cells is explained by an increased expression of different metabolism-related proteins. P10.EE induced a decrease in HBMEC cells total biomass and proliferation and decreased vessel sprouting in the chicken chorioallantoic membrane. Additionally, P10.EE potentiates paclitaxel effect in MDA-MB-231 and DU145 cells. Concluding, P10.EE can be a good candidate for cancer drug development since it affects different characteristics that dictate tumorigenesis.This work was supported by the Life and Health Sciences Research Institute, University of Minho, Portugal, and Fundacao para a Ciencia e Tecnologia (FCT) (SFRH/BD/5199712012 to V.M.G.), through Fundo Europeu de Desenvolvimento Regional-QREN-COMPETE, projects PTDC/AAC-CLI1098308/2008 and PTDC/AAC-CLI/11809212010 and also CERNAS (project PEst-OE/AGR/UI0681/2011)
The Role of Honey and Propolis in the Treatment of Infected Wounds
Honey is defined as the natural substance produced by Apis mellifera bees from plant
nectar, from secretions of the living parts of plants, or from the excretions of plant
sucking insects feeding on the living parts of plants.1,2 Honeybees collect, transform,
and combine this with specific substances of their own, and then store it and leave it
in the honeycomb to ripen and mature. This natural product is generally composed of
a complex mixture of carbohydrates and other less common substances, such as
organic acids, amino acids, proteins, minerals, vitamins, lipids, aroma compounds, flavonoids,
pigments, waxes, pollen grains, several enzymes and other phytochemicals.3 5
However, the specific composition depends on many factors, such as the nectar composition
of the source plant, the species of bee, the climate, environmental and seasonal
conditions, agricultural practices and treatment of honey during extraction and
storage.6-9
As a natural, unprocessed and easily digested food, honey plays an important role in
the human diet, and is also used in pharmaceutical and cosmetic industries.10
Modern science has studied the medical significance of honeys in healing wounds and
burns,11 oncology care,12 as well as its antioxidant and antimicrobial properties.info:eu-repo/semantics/publishedVersio
Propolis: Properties, Application, and Its Potential
Department of Microbiology and Immunology Medical University of Silesia, 41-808 ZabrzeInstitute of Organic Chemistry Centre of Phytochemistry Bulgarian Academy of Sciences, 1113 SofiaDepartment of Microbiology and Immunology Biosciences Institute UNESP, 18618-000 Botucatu, SPPedagogical University of Krakow, 31-128 KrakowDepartment of Microbiology and Immunology Biosciences Institute UNESP, 18618-000 Botucatu, S
Cinnamic Acid Is Partially Involved in Propolis Immunomodulatory Action on Human Monocytes
Propolis is a beehive product used in traditional medicine due to its biological properties. It shows a complex chemical composition including phenolics, such as cinnamic acid (Ci). The mechanisms of action of propolis have been the subject of research recently; however, the involvement of Ci on propolis activity was not investigated on immune cells. Ci effects were evaluated on human monocytes, assessing the expression of Toll-like receptors (TLRs), HLA-DR, and CD80. Cytokine production (TNF-α and IL-10) and the fungicidal activity of monocytes were evaluated as well. Data showed that Ci downregulated TLR-2, HLA-DR, and CD80 and upregulated TLR-4 expression by human monocytes. High concentrations of Ci inhibited both TNF-α and IL-10 production, whereas the same concentrations induced a higher fungicidal activity against Candida albicans. TNF-α and IL-10 production was decreased by blocking TLR-4, while the fungicidal activity of monocytes was not affected by blocking TLRs. These results suggest that Ci modulated antigen receptors, cytokine production, and the fungicidal activity of human monocytes depending on concentration, and TLR-4 may be involved in its mechanism of action. Ci seemed to be partially involved in propolis activities
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