A New Baldness Cure: Smell Receptors in the Human Scalp

Source: Morgue File

It turns out that not just your nose can detect smells—a number of other human cells harbor olfactory receptors and are capable of detecting aromatic compounds and sending a signal to the brain.

Hair follicles in the scalp have just been discovered that express a unique olfactory receptor called OR2AT4. More surprisingly, when this receptor came into contact with a specific scent—sandalwood in one report—it stimulated hair growth, instantly suggesting a new way of preventing hair loss.

Scientists had already known that the OR2AT4 receptor could spark the proliferation of keratin cells in the skin, a first step in wound healing. A team at the University of Manchester wondered whether they could also prod these receptors into growing new hair. To find out they applied synthetic sandalwood (sandalore) typically used in perfumes and beauty lotions to samples of scalp tissue donated by patients who were undergoing a face lift.

They found that when sandalwood bound itself to the receptor, it activated the secretion of a hair–growth factor called IGF–1. That is, it helped the growing phase of hair cells while also preventing them from dying. OR2AT4 evidently plays a larger role in hair growth than scientists has previously appreciated: when they added phenirat, a chemical that silences OR2AT4, hair growth stopped.

A pilot study on 20 women who suffered from female pattern baldness showed a reduction in daily hair loss. Next will be a larger, randomized study to see whether odorant molecules like sandalwood can promote hair growth and retard its loss. In science, nothing can be taken for granted, which is why further controlled studies are necessary.

Hype aside, dermatologists are excited by the possibilities raised by the pilot data. Nicola Clayton of the British Association of Dermatologists said, “It is a fascinating concept that the human hair follicle, as the authors put it, can ‘smell’ by utilizing an olfactory receptor.”

We'll have to wait to see where this research leads, but if the next trial is successful, we could be looking at a new mechanism for preventing hair loss.