The potential hair growth-promoting activity of rice bran supercritical CO 2 extract (RB-SCE) and major components of RB-SCE, linoleic acid, policosanol, γ-oryzanol, and γ-tocotrienol, were evaluated with the histological morphology and mRNA expression levels of cell growth factors using real-time reverse transcriptase-polymerase chain reaction (PCR) in C57BL/6 mice. RB-SCE showed hair growth-promoting potential to a similar extent as 3% minoxidil, showing that the hair follicles were induced to be in the anagen stage. The numbers of the hair follicles were significantly increased. In addition, mRNA expression levels of vascular endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF-1), and keratinocyte growth factor (KGF) were also significantly increased and that of transforming growth factor-β (TGF-β) decreased in RB-SCE-treated groups. Among the major components of RB-SCE, linoleic acid and γ-oryzanol induced the formation of hair follicles according to examination of histological morphology and mRNA expression levels of cell growth factors. In conclusion, our results demonstrate that RB-SCE, particularly linoleic acid and γ-oryzanol, promotes hair growth and suggests RB-SCE can be applied as hair loss treatment.
Key words rice bran supercritical CO 2 extract; hair growth-promoting activity; in vivoAlthough hair loss is not a mortal disorder, it has a great impact on a person's self-respect, mental health, and overall quality of life. Approximately 50-60 hairs are normally lost per day, which does not have a noticeable effect on appearance; however, excess loss (>100) results in baldness. Androgenetic alopecia is the most common type of hair loss, affecting millions of both men and women.1) There are many causes of hair loss in men and women, including diseases, nutritional deficiency, aging, hormone imbalance, and stress. Androgenetic alopecia may occur as early as the teenage years, but typically begin in the later decades of life. 2,3) Hair loss affects at least half of all men by the age of 50 and up to 70% of 70-year-old men.
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