Table 2.
Effects of melatonin on hair growth and pigmentation
| Growth | ||
|---|---|---|
| Species | Effect | References |
| Mouse | Influence on the hair cycle by the pineal gland | 235 |
| Weasel | Induction of molt | 236 |
| Mink | Induction of autumn molt | 237 |
| Soay rams | Stimulation of molting | 238 |
| Limousine ram | Increased HF activity and reduced prolactin plasma levels | 239 |
| Mink | Induction of winter fur growth (supposedly by inhibition of prolactin) | 240 |
| Cashmere goat | Increase of growth initializing activity of secondary HFs in springtime | 241 |
| Red deer | Premature molting of summer pelage and reduced serum prolactin concentrations | 242 |
| Merino sheep | No influence of pinealectomy on wool growth and hair density | 243 |
| New Zealand goat | Induction of pro-anagen phase | 244 |
| Cashmere goat (cultured HFs) | Increase of hair shaft elongation and DNA-synthesis | 245 |
| Domestic pig | Increase of pelage development and cycle frequency | 246 |
| Ferret | Earlier change of winter and consecutive spring coat | 247 |
| Raccoon dogs | More rapid shedding of mature underfur hairs and growth of new underfur hairs; suppression of prolactin levels | 248 |
| Siberian Husky dogs | No change in hair growth or anagen rate (topical administration) | 249 |
| Rex Rabbit offspring | Maternal melatonin supplementation increased HF density, reduced hairiness, and improved fur quality of offspring | 250 |
| Cashmere goat | Continuous subcutaneous implantation of melatonin promoted cashmere to enter the anagen 2 months earlier and induce secondary hair follicle development. | 251 |
| Human (cultured HFs) | Increase of hair shaft elongation (30 μM); Decrease of hair shaft elongation (1–5 mM) | 252 |
| Human (cultured HFs) | No influence on hair shaft elongation, matrix keratinocyte proliferation/apoptosis and hair cycling (10−12–10−6 M) | 49 |
| Human (trichograms) | Slight increase of anagen hair rate in women with androgenetic and diffuse alopecia | 253 |
| Human (clinical assessment) | Topical melatonin loaded in antioxidant nanostructured lipid carriers significantly increased hair density and hair shaft diameter when compared to topical melatonin alone in men with androgenetic alopecia | 198 |
| Pigmentation | ||
| Species | Effect | References |
| Weasel | Induction of hair color change | 236 |
| Mammalians | Effects on hair color | 254 |
| Djungarian hamster | Pattern of melatonin release induced by experimentally induced photoperiods modifies molt into summer pelage | 255 |
| Siberian hamster (cultured HFs) | Post-tyrosinase inhibition of melanogenesis (10−10–10−6 M) | 256 |
| Yellow mice (C3H/He-A*vy) | Slight reduction of coat darkening | 257 |
| Mountain hares | Season-dependent effects of melatonin on fur color | 258 |
| Djungarian hamster | Induction of the winter molt and pelage color change | 259 |
| Djungarian hamster | Change of fur color | 260 |
| Mouse | Inhibition of melanogenesis | 117 |
| Human (cultured HFs) | No effect on pigmentation (10−12–10−6 M) | 49 |
Hair follicle (HF).