Brazilian Organic-propolis Inhibits Anti-inflammatory Cytokines: in vitro and Bioinformatic Approaches

Objectives: Here, we evaluated the anti-inflammatory activity of seven types of Brazilian organic-propolis (OP) on activation of NF-κB transcription factor and TNF-α cytokine production in activated macrophages, as well as on the whole genome expression in HeLa cells.
Methods: OP samples were collected in Paraná and Santa Catarina States, Brazil, in the region covered by the following coordinates: North and West: 24°41'16.6"S 52°12'28.5"W; East: 25°22'08.8"S 49°27'03.9"W; and South: 26°40'50.4"S 50°00'56.3"W, from February to June and December 2012. The samples were evaluated by thin layer chromatography and classified into seven chromatographic types. RAW 264.7 macrophages transfected with the NF-κB-pLUC gene were stimulated with LPS (100 ng/mL) for 4 hours at 37°C, 5% CO₂. The viability of macrophages treated with the seven types of OP (0.1; 1; 10 and 100 µg/mL) was evaluated through the MTT assay. NF-kB activation was evaluated by luminescence intensity quantification (luciferase assay) and TNF-α was quantified through the ELISA assay. A translational pharmacogenomic study of OP effects was also carried out. HeLa cells were treated with OP and the whole-genome expression was evaluated using the HumanHT-12 BeadChip V4 system (Illumina).
Results: The results showed that all types of OP were not toxic up to 100 µg/mL (p<0.05). Type 6 OP showed the best activity as it reduced NF-κB activation (50% inhibition) and TNF-α release (p<0.05). Regarding the activity on whole-genome expression, ten genes related with transmigration of leukocytes to the inflammatory focus were down-regulated upon treatment with Type 6 OP.
Conclusions: This study demonstrates that Type 6 OP has promising activity by inhibiting the transmigration of leukocytes to the inflammation focus, which stands out as a potential source for the discovery of compounds with anti-inflammatory activity.