Raging female hormones take the blame for a lot of problems among women. Now, they're being blamed for a major problem among men.
The female hormone estrogen appears to play a key role in hair loss, according to a study published Tuesday by scientists at North Carolina State University.Make that fur loss. The studies were conducted in mice and have yet to be duplicated in humans.
"Our findings indicate that an estrogen receptor pathway in specific cells of the mice's hair follicles somehow acts as a switch, essentially turning on and off hair growth," said toxicologist Dr. Robert Smart in a written statement.
He and doctoral student Hye-Sun Oh presented their research Monday at a scientific meeting in Austin, Texas. The pair stumbled onto the finding during a study of pesticides and skin cancer.
While looking at the effects of a cancer-causing bug killer on mouse skin, they noticed something unusual. A group of mice in their study that had been treated with an estrogen-blocking substance started to grow new fur. The doctors were using shaved mice with temporarily inactive hair follicles. Somehow, the estrogen blockers reactivated those follicles.
"By two weeks, the visible hair growth on the treated mice was about the same as the mice who had never been shaved, while mice that had not been treated grew no hair," Smart said.
After they confirmed their new finding, the two men applied for a patent on the use of the estrogen blocker as a hair loss treatment.
That's when Toxicology Department head Dr. Ernest Hodgson heard about it. He and some colleagues have patented genetic markers linked to pesticide resistance. But no one in his department ever discovered anything with such commercial potential, Hodgson said.
"It could be good for N.C. State," Hodgson said. "It could be good for Dr. Smart. It could me good for me. I don't have any hair."
In the study, the scientists applied a small amount of the estrogen-blocking substance to the shaved mice. The substance - called ICI 182,780 - blocks a protein that triggers estrogen activity within the cell.
Without the estrogen, the mice grew fur. The researchers then treated a group of mice with active estrogen. The substance kept them bald as long as they used it.
Currently, scientists, doctors and hair-loss entrepreneurs know little about exactly what happens inside the hair cells to make men lose their hair. Both male and female hormones are suspect, but no one knows exactly what they do. Men and women both naturally produce the two hormones, but at different levels.
"I'm very excited about this because it is another handle on a process that we don't understand," said Ulrike Lichti, an investigator at the National Cancer Institute in Bethesda, Md.
Like the two NCSU researchers, she studies the link between cancer and hair cells. She said she is fairly certain that the same estrogen receptors exist in the hair cells of both mice and men.
Dr. Bill Ketcham, a Raleigh dermatologist who treats hair loss, has heard just about every pitch for a new hair loss product from the booming $800 million-a-year balding business, and he's not impressed. His first response to the NCSU study was, "Good, no more bald mice."
He, like many others in the field, thinks that male hormones - particularly a product of testosterone called dihydrotestosterone - is a main cause of baldness. So does the largest drug company in the United States. Merck and Co. plans to seek FDA approval for Propecia, a drug they say increases hair growth and prevents further hair loss in balding men.
The pill - a version of the prostate drug Proscar - works by blocking the conversion of testosterone into dihydrotestosterone.
Ketcham said the NCSU study completely contradicts previous data indicating that estrogen helps prevent baldness.
"It is a leap of faith to correlate what happens with mice that are shaved with what happens on the human head," he said. "There's a lot more going on with male pattern baldness."
(Distributed by Scripps Howard News Service.)