ETAS®50 Attenuates Ultraviolet-B-Induced Interleukin-6 Expression by Suppressing Akt Phosphorylation in Normal Human Dermal Fibroblasts

• Published in: Evidence-based complementary and alternative medicine 2018-01, Vol.2018 (2018), p.1-8
• Main Authors: Kizaki, Takako, Sakurai, Takuya, Ogasawara, Junetsu, Takanari, Jun, Koda, Tomoko, Shirato, Ken, Ohno, Hideki
• Format: Article
• Language: English
• Subjects: AKT protein; Analysis; Asparagus; Asparagus officinalis; c-Jun protein; Cell culture; Cytokines; Dextrin; Enzymes; Fibroblasts; Gene expression; Hydrogen peroxide; Inflammation; Inhibitor drugs; Interleukin 6; Interleukins; Irradiation; JNK protein; Kinases; MAP kinase; Mitogens; Natural products; Nuclear transport; Phosphorylation; Polymerase chain reaction; Protein kinase; Protein kinases; Proteins; RNA; Rodents; Skin; Transcription factors; Ultraviolet radiation; Vegetables; Western blotting
• ISSN: 1741-427X; 1741-4288
• DOI: 10.1155/2018/1547120

We recently reported that ETAS 50, a standardized extract from the Asparagus officinalis stem, exerted anti-inflammatory effects on ultraviolet-B- (UV-B-) irradiated normal human dermal fibroblasts (NHDFs) by inhibiting nuclear factor-κB p65 nuclear import and the resulting interleukin-1β (IL-1β) expression. To further elucidate the antiphotoaging potency of ETAS 50, we examined the anti-inflammatory effects on UV-B-irradiated NHDFs by focusing on the stress-activated mitogen-activated protein kinase (MAPK) and Akt signaling pathways. NHDFs were treated with 1 mg/mL of ETAS 50 or dextrin (vehicle control) after UV-B irradiation (20 mJ/cm2) for different time periods. Phosphorylation levels of c-Jun N-terminal kinase (JNK), p38 MAPK, and Akt were analyzed by western blotting. IL-6 mRNA levels were analyzed by real-time polymerase chain reaction. UV-B-irradiated NHDFs showed increased phosphorylation levels of JNK, p38 MAPK, and Akt, as well as increased mRNA levels of IL-6. ETAS 50 treatment after UV-B irradiation suppressed the increased phosphorylation levels of Akt without affecting those of JNK and p38 MAPK. ETAS 50 as well as Akt inhibitor Perifosine repressed UV-B irradiation-induced IL-6 mRNA expression. These results suggest that ETAS 50 treatment represses UV-B irradiation-induced IL-6 expression by suppressing Akt phosphorylation. The present findings demonstrate the potential of ETAS 50 to prevent photoaging by attenuating UV-B irradiation-induced proinflammatory responses in skin fibroblasts.