Spent coffee ground extract suppresses ultraviolet B-induced photoaging in hairless mice

• ESCG significantly inhibits UVB-induced ROS production in HaCaT cells.
• ESCG effectively suppresses UVB-induced wrinkle formation in hairless mice.
• ESCG significantly decreases epidermal thickness and water loss in hairless mice.
• ESCG decreases UVB-induced gene expressions of MMP2 and MMP9.
• ESCG protects collagen-1 from UVB-irradiation.

The aim of this study is to evaluate the effect of spent coffee ground (SCG) ethanol extract on UVB-induced skin aging in hairless mice. An ethanol extract of SCG (ESCG) was prepared using the residue remaining after extraction of oil from roasted SCG. High performance liquid chromatography (HPLC) analysis showed that the content of caffeine (41.58 ± 0.54 μg/mg) was higher than that of chlorogenic acid isomers (~ 9.17 μg/mg) in ESCG. ESCG significantly decreased the UVB-induced intracellular reactive oxygen species in HaCaT cells. UVB-induced wrinkle formation in mice dorsal skin was effectively reduced by ESCG administration; high dose of ESCG (5 g/L) caused the reduction of wrinkle area by 30% compared with UVB-treated control (UVBC). This result correlated with the ESCG-mediated decrease in epidermis thickness (25%). In addition, ESCG administration significantly reduced transdermal water loss (20%) and erythema formation (35%) derived from UVB exposure. Collagen type I (COL-1) level in dorsal skin was effectively recovered by ESCG administration. These results were supported by down-regulation of collagen-degrading matrix metalloproteinase 2 (MMP2) and 9 (MMP9) expressions. Our results indicate that ESCG protects mouse skin from UVB-induced photoaging by suppressing the expression of matrix metalloproteinases. Our study suggests that ESCG may be anti-photoaging agent.

Spent Coffee Ground and its effect on wrinkle formation of dorsal skin in hairless mice. Spent Coffee Grounds (SCG, down). The daily administration of hairless mice with ESCG for 12 weeks was accompanied with exposure to UVB radiation three times each week. Hairless mouse dorsal skins were photographed, and replicas made from the back skin using a Replica full kit. The wrinkle area was determined using the Image J program. NC: Normal Control; UVBC: UVB Control.Figure optionsDownload as PowerPoint slide