RESUMO
Propolis is a resinous product produced by honey bees and is known to have antitumor functions. On the other hand, histone deacetylase (Hdac) inhibitors have recently attracted attention for their antitumor effects. In this study, we examined whether Brazilian green propolis has an Hdac inhibitory activity and its contribution on antitumor effects. By in vitro Hdac activity assay, Brazilian propolis extract (BPE) significantly inhibited the enzyme activity. Actually, BPE treatment increased the intracellular histone acetylation in Neuro2a cells. Regarding antitumor effect in Neuro2a cells, BPE treatment significantly decreased cell viability. An Hdac activator theophylline significantly attenuated the effect. Then, we analyzed whether the decreasing effect on cell number was caused by cell death or growth retardation. By live/dead cell staining, BPE treatment significantly increased the dead cell number. By cell cycle analysis, BPE treatment retarded cell cycle at the M-phase. Both of these cellular effects were suppressed by addition of theophylline. These data indicate that BPE induced both cell death and growth retardation via Hdac inhibitory activity. We demonstrated that Brazilian propolis bears regulatory functions on histone acetylation via Hdac inhibition, and the effect contributes antitumor functions. Our data suggest that intake of Brazilian propolis shows preventing effects against cancer.
RESUMO
Propolis-based therapeutic agents represent this potential for the development of new drugs in dental care. The aim of a clinical-cohort study was to determine the influence of application of toothpaste enriched with Brazilian extract of propolis (EEP) on health status of oral cavity. Laboratory analysis was conducted in order to assess the chemical composition of EEP including total phenolic compounds, the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, ABTS radical cation scavenging activity, and FRAP assay. Clinical research involved two groups of subjects comprising 32 adult patients, with assessment based on the preliminary evaluation of the state of their marginal periodontium. The investigation of oral health indices API, OHI, and SBI and microbiological examination of oral microflora were also carried out. Results obtained indicated time-dependent microbial action of EEP at 50 mg/L concentration, with antimicrobial activity against Gram-positive bacteria. The total decrease of API, OHI, and SBI mean values was observed. Hygienic preparations with 3% content of Brazilian ethanol extract of green propolis (EEP) efficiently support removal of dental plaque and improve the state of marginal periodontium.