Figure 1.
Chemical structures of compounds studied.
Figure 2.
Formulations (BOX2, BMDBM) or control cream (CC) (2 mg/cm2) were spread on quartz bottom petri dishes and placed on top of the wells of cell-culture plates containing human dermal fibroblasts. The positive control (PC) was left uncoated. Cells were irradiated from above with UVA for varying lengths of time according to each assay protocol.
Figure 3.
UV absorption spectra of 25 µM ethyl acetate solutions of the compounds tested.
Figure 4.
UV absorption spectra of compounds tested (25 µM) before (black line) and after (grey line) UVA exposure (275 kJ/m2), followed by extraction from liposomes with ethyl acetate.
See materials and methods for experimental details.
Figure 5.
UV absorption spectra of formulations containing 6% concentrations of BOX2 or BMDBM, before (thick lines) and after (thin lines) UVA exposure (275 kJ/m2), followed by extraction with ethyl acetate.
See materials and methods for experimental details.
Figure 6.
Viability of HDF exposed or not exposed to UVA (365 kJ/m2), determined using the MTT assay, at time 0 and after 24 h.
HDF were either screened with formulations (BOX2, BMDBM), control cream (CC) or not screened at all (PC, positive control). Data are expressed as percentage of live cells compared to unexposed controls (−UVA). Error bars represent ± S.D. * vs PC.
Figure 7.
Flow cytometric analysis of intracellular levels of ROS in HDF, exposed or not exposed to UVA (365 kJ/m2), determined using the carboxy-DCFH-DA assay.
HDF were either screened with formulations (BOX2, BMDBM), control cream (CC) or not screened at all (PC, positive control). Data are reported as percentage of cells presenting low (□), mid () and high (▪) intracellular levels of ROS expressed in terms of carboxy-DCF fluorescence. Error bars represent ± S.D. ** vs PC.
Figure 8.
Flow cytometric analysis of mitochondrial membrane potential in HDF, exposed or not exposed to UVA (365 kJ/m2), determined using the JC-1 assay.
HDF were either screened with formulations (BOX2, BMDBM), control cream (CC) or not screened at all (PC, positive control). Data are reported as percentage of cells presenting high mitochondrial membrane potential in terms of JC-1 red fluorescence. Error bars represent ± S.D. * vs −UVA.
Figure 9.
Cellular DNA damage in HDF, exposed or not exposed to UVA (365 kJ/m2), assessed using the standard alkaline comet assay (−FPG) and the modified version with FPG (+FPG) for detection of oxidised purines.
HDF were either screened with formulations (BOX2, BMDBM), control cream (CC) or not screened at all (PC, positive control). Data are reported as the average of the median values of tail intensity. Error bars represent ± S.D. * vs PC.
Figure 10.
Gene expression analysis of MMP-1 and COL1A1 in HDF, exposed or not exposed to UVA (275 kJ/m2), assessed using qPCR.
HDF were either screened with formulations (BOX2, BMDBM), control cream (CC) or not screened at all (PC, positive control). Data are reported as normalized fold expression using the 2−ΔΔCt method. Error bars represent ± S.D. * vs PC.