Development of a high-throughput screening system for identification of novel reagents regulating DNA damage in human dermal fibroblasts

Ultraviolet (UV) radiation is a major inducer of skin aging and accumulated exposure to UV radiation increases DNA damage in skin cells, including dermal fibroblasts. In the present study, we developed novel DNA repair regulating material discovery (DREAM) system for the high-throughput screening and identification of putative materials regulating DNA repair in skin cells. First, we established a modified lentivirus expressing the luciferase and hypoxanthine phosphoribosyl transferase (HPRT) genes. Then, human dermal fibroblast WS-1 cells were infected with the modified lentivirus, and selected with puromycin to establish cells that stably expressed luciferase and HPRT (DREAM-F cells). The first step in the DREAM protocol was a 96-well-based screening procedure, involving the analysis of cell viability and luciferase activity after pretreatment of DREAM-F cells with reagents of interest and post-treatment with UVB radiation, and vice versa. In the second step, we validated certain effective reagents identified in the first step by analyzing the cell cycle, evaluating cell death, and performing HPRT-DNA sequencing in DREAM-F cells treated with these reagents and UVB. This DREAM system is scalable and forms a time-saving high-throughput screening system for identifying novel anti-photoaging reagents regulating DNA damage in dermal fibroblasts

Design of a Circularly Polarized -Slot Antenna with Isotropic Pattern for the UHF RFID Reader of WSN

In an antenna for a UHF RFID reader of wireless sensor networks (WSN), receiver sensitivity in sensing multitags from remote distances is an important performance index. This study designed a dual structured Z -slot antenna with optimized receiver sensitivity to enhance the sensitivity to a circularly polarized antenna with an isotropic pattern for a UHF RFID. Through analysis of performance in the designed antenna, the following was verified: return loss ( S 11 ) was about −62.21 dB at 925.25 MHz, antenna gain was 7.36 dBi, and Δ P r , isotropic gain deviation, was 1.3 dB. Impedance matching was about 50.069 Ω at 925.25 MHz and VSWR was from 1.001 to 1.028. Through this research it was discovered that this can be applied to the design of all RFID readers of WSN. Based on the above results, it is suggested that a circularly polarized Z -slot antenna which can enhance receiver sensitivity over a wide range can be widely applied to UHF RFID readers of WSN

Arctiin blocks hydrogen peroxide-induced senescence and cell death though microRNA expression changes in human dermal papilla cells

BACKGROUND: Accumulating evidence indicates that reactive oxygen species (ROS) are an important etiological factor for the induction of dermal papilla cell senescence and hair loss, which is also known alopecia. Arctiin is an active lignin isolated from Arctium lappa and has anti-inflammation, anti-microbial, and anti-carcinogenic effects. In the present study, we found that arctiin exerts anti-oxidative effects on human hair dermal papilla cells (HHDPCs). RESULTS: To better understand the mechanism, we analyzed the level of hydrogen peroxide (H2O2)-induced cytotoxicity, cell death, ROS production and senescence after arctiin pretreatment of HHDPCs. The results showed that arctiin pretreatment significantly inhibited the H2O2-induced reduction in cell viability. Moreover, H2O2-induced sub-G1 phase accumulation and G2 cell cycle arrest were also downregulated by arctiin pretreatment. Interestingly, the increase in intracellular ROS mediated by H2O2 was drastically decreased in HHDPCs cultured in the presence of arctiin. This effect was confirmed by senescence associated-beta galactosidase (SA-β-gal) assay results; we found that arctiin pretreatment impaired H2O2-induced senescence in HHDPCs. Using microRNA (miRNA) microarray and bioinformatic analysis, we showed that this anti-oxidative effect of arctiin in HHDPCs was related with mitogen-activated protein kinase (MAPK) and Wnt signaling pathways. CONCLUSIONS: Taken together, our data suggest that arctiin has a protective effect on ROS-induced cell dysfunction in HHDPCs and may therefore be useful for alopecia prevention and treatment strategies

Potential anti-aging effects of probiotic-derived conditioned media on human skin cells

In this study, the protective functions of bacteria-free conditioned media from Bifidobacterium and Lactobacillus species against ultraviolet radiation-induced skin ageing and associated cellular damage were investigated. The effects of ultraviolet radiation-induced reactive oxygen species production were suppressed by all conditioned media; particularly, the loss of cell viability and downregulation of collagen gene expression were significantly reversed by the conditioned media from B. longum and B. lactis. Further examination of potential anti-pigmentation effects revealed that the B. lactis-derived conditioned media significantly inhibited tyrosinase activity and alpha-melanocyte-stimulating hormone-induced melanin production in human epidermal melanocytes. Further, the conditioned media suppressed the phosphorylation of extracellular signal-related kinase, which functions as an upstream regulator of melanogenesis. Therefore, B. lactis-derived conditioned media can potentially protect against cellular damage involved in skin-ageing processes