Serum promotes hair growth by mimicking the effects of skin irritation

Skin irritation promotes hair growth in mice by stimulating their fat cells, and the serum can produce the same effect in humans without causing discomfort.

Hair loss can sometimes be treated with medications or steroid injections, but more effective treatments are being developed, such as the use of stem cells or medications that awaken dormant hair follicles.

Song Jan Lin from National Taiwan University and his colleagues several years ago, during an experiment on mice, became interested in the role of adipose tissue in hair growth. “We unexpectedly found that after skin irritation, the size of skin adipocytes increases. [fat cells] “We hypothesized that adipocytes may release fatty acids through a process called lipolysis to stimulate hair regrowth.”

To better understand the process, they repeated the experiment, looking more closely at the cells involved. They first caused eczema in shaved mice by applying the irritating compound to parts of their backs. Within 10 days, the team noticed that the mice's hair follicles were in an active growth phase, and visible hair growth was observed in these areas. This was not observed in areas without eczema or in other mice that were shaved but did not develop eczema. leather state.

The researchers noted that this appears to occur because immune cells called macrophages move into the layer of fat under the mice's skin, signaling the fat cells to release fatty acids that are taken up by hair follicle stem cells. This caused the cells to produce more mitochondria, which provide them with energy, leading to hair growth. This is consistent with previous studies that found hair plucking sends an immune signal to nearby hair folliclesencouraging them to grow more.

Eczema is not usually associated with hair growth in humans, but other forms of skin irritation have been observed, such as putting a cast on a broken limb. associated with excessive hair growth.

Lin and his team then wanted to know whether the presence of fatty acids alone, without prior irritation, stimulated hair growth, so they created serums consisting of different fatty acids dissolved in alcohol. They were applied to areas of skin of shaved mice that were not irritated, which were later compared to other areas of skin that were not treated with the serum, as well as to other shaved mice. “We found that only monounsaturated fatty acids rich in adipose tissue, such as oleic and palmitoleic acids, were effective in promoting hair regeneration when applied topically to the skin,” says Lin.

He says the researchers who patented the serum also saw promising results when applying it to human hair follicles in the laboratory, and they now plan to test different doses of the serum on people's scalps.

Lin doesn't expect the treatment to have serious side effects. “Oleic and palmitoleic acids are naturally occurring fatty acids. They are found not only in our fatty tissues, but also in many vegetable oils, so they are safe to use,” he says. “I personally applied these fatty acids dissolved in alcohol to my thighs for three weeks and found that they promoted hair regrowth.”

“The main thing is that this has not yet been tested in human skin, and animal models can be very different, especially when it comes to follicular biology,” says Christos Tsiotzios at King's College London. Similar serums are also in development: one based on plant extracts. accelerates hair growth in people within a few weeks.

However, Tziotsios says the latest research expands our understanding of hair loss and hair growth. “We knew that adipocytes play a role in the genesis of hair follicles, but this is the first time I’ve seen them used for regeneration,” he says. This may also explain why some people experience hair growth after microneedlingAccording to him, the method involves running thin needles through the scalp, making tiny punctures that trigger an immune response.