Find in Library

An unripe apple (immature fruit of <i>Malus pumila</i> Mill) contains more polyphenols than mature fruit. To explore the anti-photoaging effects of unripe apple extract (UAE), we investigated the effects of UAE on wrinkle improvement, skin moisturizing, skin inflammation, and antioxidant activities using the ultraviolet B (UVB)-irradiated SKH1-hr hairless mouse model. The mice were irradiated with UVB (0.18 J/cm²) three times per week and orally administrated UAE (100, 200, or 400 mg/kg) once a day for 15 weeks. The administration of UAE significantly prevented UVB-induced wrinkle formation and skin water loss, potentially by increasing the effects of UAE on type I collagen (COL1) and hyaluronic acid through the transcriptional regulation of COL1α (<i>COL1A1</i> and <i>COL1A2</i>), hyaluronan synthesis (<i>HAS1</i>, <i>HAS2</i>, and <i>HAS3</i>) and the matrix metalloproteinase (<i>MMP1</i>, <i>MMP9</i>, and <i>MMP13</i>) gene. Moreover, UAE significantly reduced UVB-induced skin edema, infiltrated neutrophils, and pro-inflammatory cytokine interleukin-1β (IL-1β), while increasing the anti-inflammatory cytokine IL-10. UAE also exerted anti-oxidative stress properties by increasing the glutathione content and inhibiting lipid peroxidation and superoxide anion production. The histopathological analysis demonstrated that UAE-induced anti-inflammation, anti-oxidative stress, and anti-apoptotic properties on the UVB-irradiated skin tissues. Therefore, UAE may be an effective natural resource to mitigate UVB-induced skin photoaging.