Planta Med 2007; 73 - P_485
DOI: 10.1055/s-2007-987265

Influence of avocado seed fractions (Persea americana Mill.) obtained by HSCCC on human skin keratinocytes and fibroblasts: Differences of effects in regard of tested cell types

M del R Ramos-Jerz 1, S Villanueva 2, AM Deters 3
  • 1University of Braunscheig, Institute for Food Chemistry, Schleinitzstr.20, 30106 Braunschweig, Germany
  • 2Centro de Investigación y Asistencia en Tecnología y Diseno del Estado de Jalisco (CIATEJ), 44270 Guadalajara, Jalisco, Mexico
  • 3University of Muenster, Institute for Pharmaceutical Biology and Phytochemistry, Hittorfstr. 56, 48149 Muenster, Germany

The avocado (Persea Americana, Mill.) is a tree native to the tropical forests of Mexico. Fruit oil with high contents of unsaturated fatty acids are used in cosmetical preparations to regenerate dry and rough skin, often mixed with crushed seeds in peelings. In our study, avocado seed and cotyledon extracts were separated by high speed counter current chromatography (HSCCC). Hydrophilic and slightly lipophilic crude extracts and fractions were tested on human skin cells for their cell physiology modulating activity. Human skin fibroblast and keratinocytes were incubated with fractions containing polyphenols or polysaccharides for determination of their influence on cell cytotoxicity, proliferation and differentiation. The expression of differentiation and proliferation related genes were tested by qRT-PCR. A possible antioxidant activity was investigated by the DPPH assay. The H2O-extract had no radical scavenge activity. The MeOH-, MeOH/H2O- and EtOAc-extract, also related HSCCC fractions reduced the DPPH radical up to 76%. Proliferation and cell viability of keratinocytes were significantly triggered by 10µg/ml of the H2O-, EtOAc-extract, and a HSCCC-fraction of the MeOH/H2O-extract causing up-regulation of proliferation specific genes (EGF-, insulin- and KGF-receptors, STAT6). Keratinocyte differentiation determined by cytokeratin contents was only slightly affected. The EtOAc-extract and HSCCC fractions from MeOH/H2O-extract reduced fibroblast proliferation and cell viability while the H2O-extract and other fractions slightly enhanced the proliferation rate though the cell viability of treated cells increased. In conclusion, the dermal fibroblast and epidermal keratinocytes showed different response on the incubation with avocado seed extracts. As side effect, the radical scavenging activity seems not to be equated with enhancement of cell viability or proliferation.