Persea americanaMill. Seed: Fractionation, Characterization, and Effects on Human Keratinocytes and Fibroblasts
Methanolic avocado (Persea americanaMill., Lauraceae) seed extracts were separated by preparative HSCCC. Partition and HSCCC fractions were principally characterized by LC-ESI-MS/MS analysis. Theirin vitroinfluence was investigated on proliferation, differentiation, cell viability, and gene expression on HaCaT and normal human epidermal keratinocytes (NHEK) and normal human dermal fibroblasts (NHDF). The methanol-water partition (M) from avocado seeds and HSCCC fraction 3 (M.3) were mostly composed of chlorogenic acid and its isomers. Both reduced NHDF but enhanced HaCaT keratinocytes proliferation. HSCCC fractionM.2composed of quinic acid among chlorogenic acid and its isomers inhibited proliferation and directly induced differentiation of keratinocytes as observed on gene and protein level. Furthermore,M.2increased NHDF proliferation via upregulation of growth factor receptors. Salidrosides and ABA derivatives present in HSCCC fractionM.6increased NHDF and keratinocyte proliferation that resulted in differentiation. The residual solvent fractionM.7contained among low concentrations of ABA derivatives high amounts of proanthocyanidins B1 and B2 as well as an A-type trimer and stimulated proliferation of normal cells and inhibited the proliferation of immortalized HaCaT keratinocytes.