Suppressive effects of ethanol extract of Aralia elata on UVB-induced oxidative stress in human keratinocytes / 한국영양학회지

PURPOSE: Ultraviolet (UV)-induced oxidative stress contributes to several adverse biological effects on skin. Many phenolic phytochemicals have been shown to have antioxidant properties and protect skin cells from UV-induced oxidative damage. In this study, we investigated whether or not Aralia elata (AE) has a protective effect against UVB-induced reactive oxygen species (ROS), ultimately leading to photoaging. METHODS: Phenolic content of dried AE and antioxidant properties of AE extract in 70% ethanol weredetermined by measuring DPPH and ABTS radical scavenging activities and ferric reducing antioxidant power (FRAP). The effect of AE extract on cellular ROS generation and expression levels of oxidative stress-response proteins such as superoxide dismutase (SOD)-1, catalase, nuclear factor-erythroid 2-related factor (Nrf)-2,and heme oxygenase (HO)-1 in UVB-irradiated (75 mJ/cm²) human keratinocytes (HaCaT) were further determined by 2'-7'-dichlorofluoresceine diacetate assay and Western blotting, respectively. RESULTS: The total phenolic and flavonoid contents of dried AE were 20.15 mg tannic acid/g and 18.75 mg rutin/g, respectively. The IC₅₀ of AE extract against DPPH radical was 98.5 µg/mL, and ABTS radical scavenging activity and FRAP upon treatment with 1,000 µg/mL of AE extract were 41.8 µg ascorbic acid (AA) eq./mL and 29.7 µg AA eq./mL,m respectively. Pretreatment with AE extract significantly reduced (p < 0.05) ROS generation compared to that in UVB-irradiated control HaCaT cells. Pretreatment with AE extract reversed reduction of Nrf-2 and SOD-1 protein expression and induction of HO-1 protein expression caused by UVB exposure in HaCaT cells, whereas it did not affect catalase expression. CONCLUSION: AE extract in 70% ethanol demonstrated a protective effect against UVB-induced oxidative stress and decreased expression of Nrf-2 and SOD-1 in human keratinocytes. These findings suggest that AE ethanol extract might have potential as a natural resource for a skin antiphotoaging product in the food and cosmetic industry.

Clinical evaluation in UV-B radiation microphototherapy for leukoderma / 中华医学美学美容杂志

Objective To evaluate the effectiveness of UV-B radiat io n exclusively on a variety type of leukoderma .Methods In open trail, 45 cases of a variety of leukoderma were randomly selected including preg nant striates (20 cases), stretch marks (1 case), postoperative petechia (4 case s), traumatic petechia (10 cases), radiation petechia (2 cases), generalized vit iligo (6 cases) and leukoderma with unknown cause (2 cases) were treated with Re lume UV-B re-pigmentation generator (photo range 290-320 mm), once per week with an adjusting dose for 3-20 treatments. Results 42 cases c ompleted with followed-up after 14 months of UV-B radiation microphototherapy. 64.3% (27 cases) achieved excellent results, including 10 cases of pregnant str iates, 8 cases of traumatic petechia, 4 cases of postoperative petechia and 5 c ases of peneralized vitiligo. 28.6% patients were satisfied with results (12 ca ses), including 7 cases of pregnant striates, 1 case of traumatic petechia, 1 c ase of generalized vitiligo, 1 case of stretch mark and 2 cases of leukoderma wi th unknown causes. 7.1% (3 cases) had no effect. 33.3% (14 cases) required suppl emental treatment after 2-5 months of the initial therapy. Conclusion The UV-B radiation microphototherapy is effective in restoring pigmenta tion in those affected by a variety of leukoderma except radiation petechia. The result of repigmentation is related to the type of leukoderma.