FIGURE 1.

3,4,5-Tri-O-caffeoylquinic acid (TCQA) enhanced the pigmentation in 8-week-old C3H male mouse hair shaft. (A) Time table of the performed animal experiments. The dorsal part of the mice was shaved and treated daily for 30 days with topical application of 1% TCQA and the vehicle (Milli-Q water). Upon sacrifice, the treated skin and the hair shaft were collected. (B) Regeneration of a new darker hair in TCQA-treated group compared with the controls at day 37. (C) Hair plucked from the mice’s treated area and photographed under the microscope at day 37. Hair color quantification was measured by Image J. (D) Total melanin content was determined at the end of the treatment period from the plucked hair. (E) Ctnnb1, Mitf, Tyr, Tyrp1, and Dct mRNA relative expression was measured after treatment with TCQA at day 37. The mRNA level was quantified using TaqMan real-time PCR from RNA extracted from the treated area (TCQA or Milli-Q water) from mouse dorsal back. (F) Immunohistochemistry analysis of Tyr and CD34 in the hair follicle and the epidermis of the treated skin. The first panel is the phase, the second is DAPI to stain the nucleus, the third is for Tyr staining, the fourth is for CD34 staining, and the last panel is a combination of Tyr and CD34. **Statistically significant (P ≤ 0.01) difference between vehicle-treated mice and TCQA-treated mice.