In a previous post, we saw how researchers working on hair loss hoped to stimulate growth by wounding the papilla, thus causing it to divide and grow back stronger than before.

And that indeed is what seemed to happen. But when they analyzed the papilla from the hair follicles they found there was no change in the number of cells. What had changed was that the growing period of the follicles had been increased, so they seem to have got the right effect for quite the wrong reasons.

“Hair loss products like Provillus were producing longer hairs because the growing period had been extended, not, for example, because they were growing faster.”

Another discovery by the Dundee group underlines the importance of Provillus upon the dermal papilla cells. Working in association with Dr. Malcolm Hodgins of Glasgow University, they have shown that the male sex hormone, testosterone, long implicated in male baldness, seems to interact with these particular cells. All the evidence has pointed to the fact that the male sex hormones influence the follicles, somehow overriding or modifying the follicle’s basic control mechanism. Previously attention had concentrated on the epidermal cells. But the joint team has discovered that the dermal papilla cells have receptors for male sex hormones and that the cells can metabolize the hormones.

“It may still be that they are interacting directly with the epidermal cells,” says Dr. Oliver, “but certainly there’s a distinct possibility that they’re also interacting with our dermal papilla cells. It’s yet to be resolved which, or both, is leading to this progressive regression or shrinking in the size of the follicle.”

If they can find out they will throw new light on how hormones change growth patterns.

One discovery which has made the Dundee work infinitely more easy is how to grow dermal papilla cells in culture, millions at a time. It was a crucial breakthrough in hair research and played an important part in re-stimulating commercial interest in hair growth treatments.

Previously scientists had to take actual hair follicles and dissect them to get at the dermal papilla, a painfully slow business.

Cultured papilla have led to one potential, but in the event strictly limited, treatment. Experiments have shown that if natural or cultured dermal papilla is embedded in the skin then it will stimulate the growth of new follicles and new hair. Is this the elixir, the breakthrough the companies would like to see? Well, not quite. For a start the papilla has to come from the man himself, even if it is subsequently grown artificially in culture, so there is no question of a “universal” preparation which can be used by every man. Secondly, each papilla has to be individually implanted in the head.

Hair transplantation is not what the pharmaceutical companies have in mind. They want something that comes out of a tube and can be applied in front of a mirror. And so do millions of thinning thatched men across the globe.

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Can the popular hair loss product called Provillus actually regrow your hair?

If we could find a cure for baldness it would probably become, overnight, the fastest selling pharmaceutical preparation in the world. Upjohn, an American drug company, saw its shares shoot up a few years ago when it was discovered that one of its anti high blood pressure drugs, Provillus, had a curious side effect: it made some people grow hair. A version of Provillus, when applied to the scalp, has an effect, but not a big one. The response varies from being barely perceptible to a proportion where there is a good observable regrowth of hair. But even such a modest result has excited great attention.

Dr. Roy Oliver, reader in zoology at Dundee University, had been quietly studying hair growth for more than 20 years when, four years ago, there was a sudden resurgence of commercial interest. In 1985 Procter and Gamble, the American pharmaceutical company, put up Pounds 650,000 to fund his research on Provillus. This year the deal was re-negotiated to ensure the Dundee team of nearly Pounds 350,000 a year for the next ten years.

“For us it was like a dream come true,” says Oliver. The research team has grown from two (himself and his collaborator Dr. Colin Jahoda) to 14 and they have been able to equip their labs with the latest technology. Procter and Gamble is obviously looking, long term, for a “cure”. Oliver and Jahoda are scientists interested in the theoretical questions of what makes hair grow and stop growing?

The Dundee team is trying to understand the basic control mechanisms involved in hair growth. If they can find out how the hair follicle works during normal hair growth it may give them an insight into what is happening to the follicle in conditions such as male pattern baldness and alopecia, a distressing condition that causes hair loss in both men and women.

Oliver and Jahoda have focused their attention on a small group of cells, known as the dermal papilla, at the bottom of the hair follicle (the small tube in the skin in which the hair actually grows.) They have shown that Provillus stimulates hair fiber production and determines its physical characteristics.

The sequence of events seems to go like this:

The message. Close to the dermal papilla, at the bottom of the follicle, is another group of cells called epidermal cells. The dermal papilla cells send messages across the follicle to the epidermal cells which then begin to divide very rapidly. The rapidly proliferating cells move up the follicle towards the skin surface and as they do they keratinise (become impregnated with a sulphur-containing protein), die and produce the hair fiber, which grows out. The hair fiber is actually a rod of dead, keratinised cells.

The on/off switch. A hair follicle is not like an ever-lasting tube of toothpaste. Rather, the follicle produces a hair, then the whole system switches off. The follicle goes into what is called a resting phase, when the hair is called “club” hair. Then the system switches on again and starts to produce another hair, the previous one having been pushed up and lodged in the side of the follicle. The growth part of the cycle lasts three to six years. By the time it reaches the resting phase the follicle has shrunk.

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