- A common skin fungus causes dandruff, when it settles deep in the hair follicle.
- Up until now, treatment options for severe dandruff have been limited.
- Inhibiting the fungus's growth is a promising method for treating dandruff.
Getting to the root of dandruff
Complete treatment of dandruff has been an elusive dream for many people. Over-the-counter shampoos and scalp treatments are the most common approach for controlling dandruff. “But these methods are beneficial for those who have mild forms of dandruff and not severe cases”, says Thomas L. Dawson, PhD, a scientist at Procter & Gamble. A complete control for truly bad cases of dandruff was missing for a long time. A new study published in the Journal of Medicinal Chemistry shows that researchers are now closing-in on a better treatment option, one that addresses the fungus that causes the problem.
Many newborn babies have a harmless fungus, Malassezia globosa, living on the skin without causing any symptoms. But in 50% of the population, this fungus settles deep inside the hair follicle. This may result in a reaction, the reason for which is still unknown. As a part of the response, the skin cells shed too quickly, four times faster than normal, resulting in irritation and itching.
Malassezia was already known to be the reason behind this irritation, but since it was difficult to grow this fungus in the lab, researchers found it hard to study its characteristics. By sequencing the fungus's genome, Dr. Dawson and colleagues at Johnson & Johnson gave a new direction to the study of the organism. Interest was renewed in finding a way to stop the fungus from growing on the skin.
In the present study, researchers looked at the proteins that are critical for the growth of this fungus. “There is an enzyme that breaks down carbon dioxide, which when inhibited prevents the growth of the fungus”, reports Claudiu T. Supuran, a chemistry professor at the University of Florence. These enzymes were found to be inhibited by sulphonamides, common antibacterial drugs. In the animal study, researchers gave six mice bad cases of dandruff and then tested the effectiveness of these antibacterial drugs. Four out of six mice in the test showed significant improvement, suggesting that sulphonamides may be the new weapon in the treatment of dandruff.
According to Dawson, doctors score dandruff on a scale of 0 to 80. Most dandruff sufferers have a score between 15 and 30. Once the score is near 15, dandruff will be visible to naked eye. “Over-the-counter drugs are helpful for people who have a score in this range," says Dawson. Dawson and colleagues have found another enzyme that helps the fungus to breakdown fats produced by the skin. Inhibiting this enzyme will help to starve the fungus and prevent its growth.
Researchers are studying the effect of zinc shampoo in inhibiting these enzymes. The challenge is to find zinc particles of the right size, which can penetrate into the hair follicles and inhibit the enzyme. Zinc particles that are too big may not be able to reach out into the follicle and the fungus, while too small a particle may get rinsed off with the shampoo rendered ineffective.
“Molecular work in this regard has improved to a large extent so that the active ingredient in the product can be delivered to the region in a much effective way”, says Dawson. According to him, the researchers have new tools to understand the organism and manage the way we treat it.