title: Anti-wrinkle effects of Sargassum muticum ethyl acetate fraction on ultraviolet B-irradiated hairless mouse skin and mechanistic evaluation in the human HaCaT keratinocyte cell line.
abstract: The present study investigated the photoprotective properties of the ethyl acetate fraction of Sargassum muticum (SME) against ultraviolet B (UVB)‑induced skin damage and photoaging in a mouse model. HR‑1 strain hairless male mice were divided into three groups: An untreated control group, a UVB‑irradiated vehicle group and a UVB‑irradiated SME group. The UVB‑irradiated mice in the SME group were orally administered with SME (100 mg/kg body weight in 0.1 ml water per day) and then exposed to radiation at a dose of 60‑120 mJ/cm2. Wrinkle formation and skin damage were evaluated by analysis of skin replicas, epidermal thickness and collagen fiber integrity in the dermal connective tissue. The mechanism underlying the action of SME was also investigated in the human HaCaT keratinocyte cell line following exposure of the cells to UVB at a dose of 30 mJ/cm2. The protein expression levels and activity of matrix metalloproteinase‑1 (MMP‑1), and the binding of activator protein‑1 (AP‑1) to the MMP‑1 promoter were assessed in the HaCaT cells using western blot analysis, an MMP‑1 fluorescent assay and a chromatin immune‑precipitation assay, respectively. The results showed that the mean length and depth of the wrinkles in the UVB‑exposed hairless mice were significantly improved by oral administration of SME, which also prevented the increase in epidermal thickness triggered by UVB irradiation. Furthermore, a marked increase in collagen bundle formation was observed in the UVB‑treated mice with SME administration. SME pretreatment also significantly inhibited the UVB‑induced upregulation in the expression and activity of MMP‑1 in the cultured HaCaT keratinocytes, and the UVB‑enhanced association of AP‑1 with the MMP‑1 promoter. These results suggested that SME may be useful as an anti-photoaging resource for the skin.
authors: KM Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Republic of Korea.
authors: Jae Hyoung
authors: JH
authors: Song
authors: School of Medicine, Jeju National University, Jeju 63243, Republic of Korea.
authors: Mei Jing
authors: MJ
authors: Piao
authors: School of Medicine, Jeju National University, Jeju 63243, Republic of Korea.
authors: Xia
authors: X
authors: Han
authors: School of Medicine, Jeju National University, Jeju 63243, Republic of Korea.
authors: Kyoung Ah
authors: KA
authors: Kang
authors: School of Medicine, Jeju National University, Jeju 63243, Republic of Korea.
authors: Hee Kyoung
authors: HK
authors: Kang
authors: Jeju Biodiversity Research Institute, Jeju High‑Tech Development Institute, Jeju 63612, Republic of Korea.
authors: Weon Jong
authors: WJ
authors: Yoon
authors: Jeju Biodiversity Research Institute, Jeju High‑Tech Development Institute, Jeju 63612, Republic of Korea.
authors: Mi Hee
authors: MH
authors: Ko
authors: Department of Chemistry, College of Natural Sciences, Jeju National University, Jeju 63243, Republic of Korea.
authors: Nam Ho
authors: NH
authors: Lee
authors: KM Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Republic of Korea.
authors: Mi Young
authors: MY
authors: Lee
authors: KM Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Republic of Korea.
authors: Sungwook
authors: S
authors: Chae
authors: School of Medicine, Jeju National University, Jeju 63243, Republic of Korea.
authors: Jin Won
authors: JW
authors: Hyun
mesh_terms: D000085:Acetates / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D002460:Cell Line; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects* / Q000528:radiation effects*; D008297:Male; D008812:Mice, Hairless; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D011837:Radiation-Protective Agents / Q000737:chemistry / Q000494:pharmacology*; D044647:Sargassum / Q000737:chemistry*; D012867:Skin / Q000166:cytology / Q000187:drug effects / Q000528:radiation effects; D015595:Skin Aging / Q000187:drug effects* / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D000085:Acetates; D010936:Plant Extracts; D011837:Radiation-Protective Agents; C007650:ethyl acetate