RESUMO
Damiana (Turnera diffusa), of the family Passifloraceae, has been widely studied for its pharmacological effects, especially for antioxidant and antibacterial actions. However, there are limited scientific findings describing its antiphotoaging effects on the skin. In the present study, the underlying molecular mechanisms of the protective effect of Damiana were investigated in keratinocytes (HaCaTs) and normal human dermal fibroblasts (HDFs) subject to UVB irradiation. The mRNA expression of matrix metalloproteinases (MMPs) and procollagen type I was determined by reverse transcription-polymerase chain reaction. The protein expression of antiphotoaging-related signaling molecules in the activator protein-1 (AP-1) and nuclear factor erythroid 2-related factor 2 (NRF2)/antioxidant response element (ARE) pathways was assessed by Western blotting. We observed that Damiana blocked the upregulated production of reactive oxygen species induced in UVB-irradiated HaCaTs and HDFs in a dose-dependent manner. Treatment with Damiana also significantly ameliorated the mRNA expression of MMPs and procollagen type I. In addition, the phosphorylation level of c-Jun and c-Fos was also decreased through the attenuated expression of p-38, p-ERK, and p-JNK after treatment with Damiana. Furthermore, the treatment of cells with Damiana resulted in the inhibition of Smad-7 expression in the TGF-ß/Smad pathway and upregulated the expression of the Nrf2/ARE signaling pathway. Hence, the synthesis of procollagen type I, a precursor of collagen I, was promoted. Collectively, these results provide us with the novel insight that Damiana is a potential source of antiphotoaging compounds.
RESUMO
The antimicrobial activities of isolated compounds from seed extracts of Moringa oleifera and synergistic antimicrobial efficacy through hybridized complex of organic-inorganic composite materials were studied. The two main components of the Moringa oleifera seed were isolated and determined to be niazimicin and 4-(α-L-rhamnosyloxy)-benzyl isothiocyanate (RBI). The antimicrobial activity of the separated compounds of the Moringa oleifera seed were tested in vitro against 3 bacterial species and 2 fungal species by the paper disc diffusion assay and broth dilution methods. Both compounds showed antimicrobial activity against tested species and RBI was more effective than niazimicin. The MIC of RBI on S. aureus, E. coli, P. aeruginosa, C. albicans, and A. niger was 0.005%, 0.1%, 0.5%, 0.5%, and 0.5%, respectively, while the MIC of niazimicin on S. aureus was 0.1%. Next, we investigated the combined antimicrobial action of mesoporous ZnO and RBI by incorporating the compound within the pore of mesoporous ZnO. The MIC of mesoporous ZnO with RBI on S. aureus, E. coli, P. aeruginosa, C. albicans, and A. niger was 0.001%, 0.01%, 0.5%, 0.1%, and 0.1%, respectively. A synergistic effect of RBI with mesoporous ZnO was shown. From these results, the mesoporous ZnO could act as a reservoir for RBI and mesoporous ZnO with RBI could be used for cosmetic preservatives.
