New research has found that pheomelanin, the pigment that gives hair its red color, can help reduce oxidative stress in cells.
A pigment responsible for red hair and orange feathers can help protect cells from toxic damageaccording to new research in PNAS Nexus.
Scientists who study the black voicethe orange to red pigment found in the hair, skin and feathers of birds, discovered that its production can help cells control excessive levels of the amino acid cysteine. Although cysteine is essential for normal cellular function, too much of it can trigger oxidative stressdamaging cells and tissues.
The team, led by scientists from the National Museum of Natural Sciences in Spain, investigated whether the production of pheomelanin could serve as a kind of biological safety valve for convert to potentially harmful cysteine into a harmless pigment. To test the hypothesis, the authors turned to zebra finches, a species of bird known for its colorful plumage and its usefulness as a biological model.
Male zebra finches naturally produce pheomelanin in their feathers, while females do not. In the study, some male finches were treated with a medication that blocked the production of pheomelaninwhile others received no treatment. Both groups were then fed extra cysteine for a month, explains .
The results were surprising. Males that were unable to produce pheomelanin presented significantly higher levels of damage oxidative compared to males who still managed to synthesize the pigment. This suggests that the conversion of excess cysteine into pheomelanin helped protect your cells from damage.
Female finches, which do not naturally produce pheomelanin, were not affected by the drug that blocked production of the pigment. When given extra cysteine, they showed slightly greater oxidative damage than females on a normal diet, but the increase was small and not considered statistically significant. Taken together, the findings support the idea that excess cysteine can damage cells and that pheomelanin production can help counteract this damage.
Researchers believe the findings could also help explain certain features in humans. In people, pheomelanin is generally concentrated in areas such as the lips, nipples and genitals. Individuals with genetic variants linked to red hair, however, produce more pheomelanin in their hair and skin.
Pheomelanin has long been associated with a increased risk of melanomaparticularly in redheaded individuals. But new research suggests that the pigment may also offer an important benefit by helping cells regulate cysteine levels, converting excess cysteine into pigment rather than allowing it to cause oxidative damage.
