Topical application of spent coffee ground extracts protects skin from ultraviolet B-induced photoaging in hairless mice

Photochem Photobiol Sci. 2016 Jun 8;15(6):779-90. doi: 10.1039/c6pp00045b. Epub 2016 May 19.

Abstract

The aim of this study was to evaluate the protective effect of spent coffee ground (SCG) on ultraviolet (UV) B-induced photoaging in hairless mice. The oil fraction (OSCG) and ethanol extract (ESCG) of SCG were prepared from SCG. OSCG contained a much higher level of caffeine (547.32 ± 1.68 μg mg(-1)) when compared to the sum of its chlorogenic acid derivatives (∼119 μg mg(-1)), and pyrazines were the major aromatic compounds in OSCG. OSCG effectively inhibited the UVB-induced increase in intracellular reactive oxygen species in HaCaT cells. Topical application of OSCG or ESCG significantly reduced the UVB-induced wrinkle formation in mice dorsal skin. The combined application of OSCG and ESCG (OEH) led to a decrease in the wrinkle area by over 35% when compared with the UVB-treated control (UVBC). Epidermal thickness was also reduced by 40%. This result was connected to the significant reduction in transdermal water loss (27%) and erythema formation (48%) that result from UVB irradiation. Polarization-sensitive optical coherence tomography (PS-OCT) and antibody-based histological analyses showed that OSCG and ESCG effectively suppressed the UVB-induced decrease in collagen content. The level of type 1 collagen (COL1) in the OEH group was enhanced by around 40% compared with the UVB control group (UVBC). This was attributed to the down-regulation of matrix metalloproteinases (MMP2, 9, and 13), which are known to be responsible for collagen destruction. Our results indicate that topical treatment with OSCG/ESCG protects mouse skin from UVB-induced photoaging by down-regulating MMPs; therefore, suggesting the potential of SCG extracts as a topical anti-photoaging agent.

MeSH terms

  • Animals
  • Body Water / drug effects
  • Body Water / radiation effects
  • Caffeine / chemistry
  • Caffeine / pharmacology
  • Cell Line
  • Cell Survival / drug effects
  • Cell Survival / radiation effects
  • Chlorogenic Acid / analogs & derivatives
  • Coffee* / chemistry
  • Collagen / metabolism
  • Epidermis / drug effects
  • Epidermis / metabolism
  • Epidermis / pathology
  • Epidermis / radiation effects
  • Erythema / drug therapy
  • Erythema / etiology
  • Erythema / metabolism
  • Erythema / pathology
  • Ethanol / chemistry
  • Humans
  • Male
  • Matrix Metalloproteinases / metabolism
  • Mice, Hairless
  • Oils / chemistry
  • Phytotherapy*
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Pyrazines / chemistry
  • Pyrazines / pharmacology
  • Reactive Oxygen Species / metabolism
  • Skin Aging / drug effects*
  • Skin Aging / pathology
  • Skin Aging / physiology
  • Ultraviolet Rays / adverse effects*

Substances

  • Coffee
  • Oils
  • Plant Extracts
  • Pyrazines
  • Reactive Oxygen Species
  • Chlorogenic Acid
  • Caffeine
  • Ethanol
  • Collagen
  • Matrix Metalloproteinases