14 citations
,
September 2017 in “General and comparative endocrinology” In this study, researchers observed that in barn owls, the relationship between black feather spot size and testosterone levels varied by age and sex, suggesting involvement of genes regulating both traits rather than direct influence of testosterone on feather coloration.
6 citations
,
September 2022 in “Frontiers in pharmacology” In this study, Epimedii Folium extract was found to enhance melanin production and promote pigmentation through mechanisms involving the MAPK/ERK1/2 pathway in both in vitro and in vivo models.
April 2026 in “Biomolecules” This study reported that discarded squid ink was used to develop a high-performance, environmentally friendly hair dye that offers a stable deep black color, UV protection, and preserves hair structure, while showing excellent biosafety in lab tests.
86 citations
,
August 2000 in “Pigment cell research” This study observed that melanogenesis in human hair follicles is linked to anagen phases, with melanocyte activity and enzyme expression being region-specific to the nascent bulb.
10 citations
,
May 2012 in “PloS one” This study found that non-pigmented hair follicles have significantly lower expression of nucleotide excision repair genes, which may be associated with reduced melanin production capacity in these follicles.
