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089
The Effect of Sophora Root Extract on the Anagen Elongation
and Isolation of Active Compounds
T. Takahashi, C. Hamada, A. Ishino, K. Kobayashi,
T. Kimura, K. Komatsu and M. Tajima Shiseido Basic Research
Center, Yokohama, Japan
Androgenetic alopecia is characterized by the
gradual miniaturization of hair follicles (vellus hair) resulting
from the decrease in the duration of anagen phase. Thus, the
anagen elongation is thought to be the most effective for
the improvement of androgenetic alopecia. In the course of
screening plant extracts for anagen elongation activity, the
extract of dried roots of Sophora Flavescens Aiton (SRE),
which is wellknown as a Chinese traditional medicine, was
found to possess potent anagen elongation activity using human
hair follicle organ culture. When anagen hair follicles were
cultured in Williams E medium in the presence of SRE, hair
shaft elongation was significantly accelerated compared with
those cultured in the absence of SRE. In anagen hair follicles,
the proliferating cells are distributed in epithelial cells,
such as hair matrix cells and outer root sheath cells (ORSC).
The elongation of anagen phase was estimated by growth stimulation
of hair follicle epithelial cells. We used a serum-free culture
system of human ORSC to estimate the effect of anagen elongation.
When human ORSC was cultured in the presence of SRE, one ppb
of dry residue was sufficient for the growth stimulation of
ORSC. These results suggest that SRE is effective for anagen
elongation because of the stimulation of the proliferation
of hair follicle epithelial cells. In order to isolate active
compound for anagen elongation, SRE was fractionated by solvent
extraction and subsequent silica gel chromatography. The hydrophobic
fraction showed activity for ORSC growth stimulation. Further
purification showed two independent active compounds. When
their structures were elucidated using NMR and FAB-MS method,
these were two pterocarpan derivatives, medicarpin and maakiain,
and exhibited significant acceleration of ORSC proliferation.
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