Effects of Ginseng Rhizome and Ginsenoside Ro on Testosterone 5α-Reductase and Hair Regrowth in Testosterone-Treated Mice

The study from 2011 examined the potential of ginseng rhizome extracts, particularly from red ginseng (RG), and ginsenoside Ro in promoting hair re-growth and inhibiting testosterone 5α-reductase (5αR), an enzyme involved in androgenetic alopecia. The extracts showed dose-dependent 5αR inhibitory effects, with white ginseng (WG) showing the highest inhibition at 68.9% at 1000 µg/mL. Ginsenoside Ro had an IC50 value of 259.4 µM, while ginsenoside Rg3, also found in RG, had an IC50 value of 86.1 µM, indicating strong inhibitory activity. Topical application of these substances on testosterone-treated C57BL/6 mice prevented the suppression of hair re-growth normally caused by testosterone. The study concluded that RG rhizome extracts, rich in ginsenoside Ro, could be effective in hair re-growth products for androgenetic alopecia. This was the first demonstration of ginsenoside Ro's in vivo hair re-growth effects. The number of mice used in the hair re-growth test was 10 per group.