Brazilian Green Propolis Extract Synergizes with Protoporphyrin IX-mediated Photodynamic Therapy via Enhancement of Intracellular Accumulation of Protoporphyrin IX and Attenuation of NF-κB and COX-2

Abstract

Brazilian green propolis (BGP) is noted for its impressive antitumor effects and has been used as a folk medicine in various cultures for many years. It has been demonstrated that BGP could enhance the cytotoxic effect of cytostatic drugs on tumor cells. Photodynamic therapy (PDT) is a therapeutic approach used against malignant cells. To assess the synergistic effect of BGP extract on protoporphyrin IX (PpIX)-mediated photocytotoxicity, MTT assays were performed using A431 and HeLa cells. TUNEL assay and Annexin V-FITC/PI staining were performed to confirm the induction of apoptosis. Western blotting analysis was performed to examine the pro-apoptotic proteins, anti-apoptotic proteins and inflammation related proteins in A431 cells. Intracellular accumulation of PpIX was examined by flow cytometry. The synergistic effect of BGP extract in PpIX-PDT was also evaluated with a xenograft model. Our findings reveal that BGP extract increased PpIX-mediated photocytotoxicity in A431 and HeLa cells. PpIX-PDT with BGP extract treatment resulted in a decrease in Bcl-xL and an increase in NOXA, Bax and caspase-3 cleavage. The protein expression levels of p-IKKα/β, NF-κB and COX-2 were upregulated by PpIX-PDT but significantly attenuated when in combination with BGP extract. BGP extract was also found to significantly enhance the intracellular accumulation of PpIX in A431 cells. BGP extract increased PpIX-mediated photocytotoxicity in a xenograft model as well. Our findings provide evidence for a synergistic effect of BGP extract in PpIX-PDT both in vitro and in vivo.

IL-21 Stimulates the expression and activation of cell cycle regulators and promotes cell proliferation in EBV-positive diffuse large B cell lymphoma

“…After blocking the membranes for 2 h at room temperature with 5% nonfat dried milk, membranes were incubated with primary antibody overnight at 4 °C. After incubation with secondary antibody for 2 h at room temperature, immunoreactive bands were visualized by Immobilon Western chemiluminescent HRP substrate (Millipore, Darmstadt, Germany) 62 . The following antibodies were used as primary antibodies in immunoblotting: AC-15 (mouse anti-human β-actin; Sigma-Aldrich), 3H2-E8 (mouse anti-Epstein-Barr Virus Blimp-1, Novus); 0211 (mouse anti-Epstein-Barr Virus EBNA-1, Santa Cruz), CS.1–4 (mouse anti-Epstein-Barr Virus LMP; DAKO), D84C12 (rabbit anti-c-Myc), 124H6 (mouse anti-human Stat3), M9C6 (mouse anti-human Phospho-Stat3 (Tyr705)), 9F6 (rabbit anti-human c-Fos), 60A8 (rabbit anti-human c-Jun), D52F9 (rabbit anti-human Cyclin D2), HE12 (mouse anti-human Cyclin E1), 4H1 (mouse anti-human Rb), and 9308 (rabbit anti-human Phospho-Rb (Ser807/811)) from Cell Signalling Technology.…”

Evidence-Based Studies and Perspectives of the Use of Brazilian Green and Red Propolis in Dentistry

“…The Africanized bees of the Southeast region are able to produce propolis from buds of leaves of B. dracunculifolia not yet expanded, guaranteeing a product with high concentrations of phenols and Artepillin C (3,5-diprenyl-4-hydroxycinnamic acid), a compound only found in propolis in the Southeast region on Brazil. 12 In this way, caffeic ferulic, p- coumaric acids, kaempferol, kaempferide, and Artepillin C are the main constituents of the Brazilian green propolis. 13 Artepillin C presents several activities such as antioxidant, antimicrobial, anti-inflammatory, antigenotoxic, antiangiogenic, and anticancer properties.…”

“…Brazilian red propolis is obtained by bees from the species Apis mellifera mainly from the sap of Dalbergia ecastophyllum , which is a leguminous plant found in the northeastern mangroves of Brazil. 12 One of its botanical origin is a legume identified as D. ecastophyllum L., found in a region of tropical coastal climate, specifically the mangrove region. Its stem is reddish, so the product of propolis accompanies the coloration.…”

Propolis: A useful agent on psychiatric and neurological disorders? A focus on CAPE and pinocembrin components

“…Thereafter, our group demonstrated that both the oil and hydroalcoholic extract of propolis elicits anxiolytic effects on an arena and elevated plus‐maze paradigm 13,20 . In the studies described above, CAPE and pinocembrin were absent in the propolis constituents; however, other phenolic hydroxyl group, including CA and its correlates, which have reported anxiolytic effects, were sometimes present 13,68,69 …”