Steroidogenic isoenzymes in human hair and their potential role in androgenetic alopecia.

Herb/Nutrient Research Links:
Echinacea||Ginseng|| Ginkgo||Milk thistle|| St. John's wort||Saw palmetto|| Bay||Bilberry|| Black cohosh||Licorice|| DHEA||Royal Jelly|| Garlic||Ginger|| Coenzyme Q10||Lutein|| rutin

DreamPharm Products:

Dermatology 2003;206(2):85-95

Steroidogenic isoenzymes in human hair and their potential role in androgenetic alopecia.

Androgenetic alopecia (AGA) is the most common type of hair loss. The relatively strong concordance of the degree of baldness in fathers and sons is not consistent with a simple Mendelian trait, and a polygenic basis is considered to be most likely. So far, the predisposing genes for AGA are unknown and we do not understand the molecular steps involved in androgen-dependent beard growth versus androgen-dependent hair loss, but AGA can be defined as a dihydrotestosterone (DHT)-dependent process with continuous miniaturization of sensitive hair follicles. The type 2 5alpha-reductase plays a central role by the intrafollicular conversion of testosterone to DHT. However, due to the increasing knowledge in this field, we now know that there are many more steroidogenic enzymes involved in the onset and development of AGA, and this article shall provide a critical overview of recent discoveries.

Harv Mens Health Watch 2002 Nov;7(4):6-7

Baldness: Does appearance matter?
It lacks the pain of a heart attack, the threat of prostate cancer, and the complications of hypertension. Still, despite the best efforts of Michael Jordan, millions of men are distressed by hair loss.

Normal hair growth
Whether straight or curly, hair grows in a cyclical pattern that has three phases: growth (called the anagen phase by biologists), involution (catagen), and rest (telogen). The growth phase lasts the longest; its duration determines how long a hair will grow. That's why eyebrow hairs stay short (growth phase, 13 months) while scalp hairs are long (5–8 years). After the growth phase, each follicle undergoes a brief period of involution, when some of its cells die off. Then comes a spell of inactivity. At the end of the rest phase, the hair falls out of its follicle and the cells get back to work, growing a new hair. In humans, each hair follicle cycles independently; that's why humans don't "shed" each season, as many animals do.

At birth, the human body is covered by about 5 million hair follicles, including about 100,000 on the scalp. This number remains constant throughout life, but the activity and productivity of each follicle varies according to a person's age.

In a healthy scalp, more than 90% of hair follicles are in the growth phase, less than 1% are undergoing involution, and 5%–10% are resting.

Fragile follicles
Hair follicles contain living cells. Like all cells, they can be damaged, which halts hair growth. If the problem is mild, the follicle recovers and resumes growing hair, but if it's severe, the damage may be permanent.

Any severe stress, physical or emotional, can damage hair follicles, halting hair growth. That's why patients often lose their hair two or three months after a major illness or traumatic life event. It's a temporary problem technically known as telogen effluvium. It's easy to recognize with a simple pull test: If you can extract more than five or six hairs with a single pull, you're likely to have telogen effluvium, and you'll most likely grow back all your hair within a few months, even without therapy.

Medication can damage hair follicles; chemotherapy drugs are the leading examples. Less often, toxic chemicals, radiation, thyroid disease, or infections can do the job. Skin diseases that produce scarring can also result in hair loss, which may be permanent. Fortunately, all these problems are uncommon. Contrary to popular belief, common woes like seborrhea and dandruff do not cause hair loss.

Normal hair loss
Men with male pattern baldness may not regard it as normal, but it is. Like it or not, losing scalp hair is part of the human condition. It may cause psychological distress that's important in its own right, but it's not a disease.

Virtually all people, male and female, lose scalp hair as they age. In a sense, male pattern baldness, known technically as androgenic alopecia, is just an exaggerated form of a normal event. It has two requirements: a genetic predisposition and the male hormone testosterone.

The genetics of male baldness are complex. Most experts believe that one gene is responsible, but several may play a role. In any case, the abnormal gene has variable penetrance, which means it is more likely to produce hair loss in some men than others. The abnormal gene can be passed down from a mother or a father, and boys or girls can inherit it. But men are much more likely to suffer from the gene's activity because they have the second requirement, testosterone.

Testosterone makes the man: It is responsible for the large muscles, strong bones, and deep voice that characterize the gender. It is also essential for male genital development in fetal life, for the sexual awakening of adolescence, and for libido and fertility in adulthood. Testosterone acts directly on tissues to produce all these effects, but it acts indirectly on the prostate and on hair follicles. In these areas, an enzyme called 5-alpha reductase converts testosterone to dihydrotestosterone (DHT), and DHT acts on the tissues.

DHT stimulates the growth of hair follicles in the beard and body, but it has the opposite effect on scalp hair. Hair loss usually starts between the age of 17 and 40; by 50, about half of all men display some degree of male pattern baldness. It usually begins with a receding hairline over the temples, followed by thinning of the hair at the vertex, or top of the scalp. The rate of hair loss varies considerably; some men go bald in less than 5 years, but most lose their hair gradually, over 15–25 years. On average, men with androgenic alopecia lose about 5% of their scalp hair each year, but the process can slow down or speed up without apparent reason.

Although it's small comfort to balding men, their hair follicles don't actually disappear. Instead, each successive growth phase gets shorter and each resting phase longer. With an abbreviated growth phase, the hair becomes shorter and finer; with an extended resting phase, the hairs are less tightly anchored to the scalp, so they fall out during washing or combing.

Adverse effects
Male pattern baldness is not a disease. Its only consequences are cosmetic, and its only implications are psychological.

Although baldness does not cause disease, it may be a marker for increased cardiac risk. The Harvard-sponsored U.S. Physicians' Health Study found that men with bald spots were more likely to develop coronary artery disease than men with full heads of hair; mild vertex baldness was linked to a 23% increase, moderate baldness to a 32% rise, and severe baldness to a 36% increase in risk. The effect was greatest in men with hypertension or high cholesterol levels. Frontal baldness, the receding hairline, was not associated with cardiac risk.

Treatment
Doctors may not think male pattern baldness is a problem, but many men disagree. That's why 33 million Americans spend about $1.5 billion a year to replace or restore lost hair.

Treatment takes many forms, ranging from wigs and toupees to scalp surgery and hair transplants. Many men prefer wigs to surgery. Some are worn on top of existing hair; others are interwoven with a man's own hair. Interwoven wigs have to be adjusted every few weeks as the natural hairs grow, adding to the expense and inconvenience.

For generations, a bewildering array of concoctions claiming to restore lost hair have been sold to gullible men. In 1989, the FDA issued guidelines that cleared the shelves of many expensive but worthless products. At present, only two drugs are approved for male pattern baldness.

When sold in tablet form, minoxidil is a prescription drug for hypertension. But for more than 10 years it has also been available as Rogaine, a nonprescription lotion for hair loss. Regular Rogaine solution or spray contains 2% minoxidil, extra strength Rogaine, 5%. The drug increases the duration of the hair follicles' growth phase, but it works only on follicles that are still active, and its benefits last only as long as it is used regularly. Rogaine is more effective for bald spots than receding hairlines, but it's only partially effective at that; in one study, 36% of men who had used the product for several years felt it was worth the time and money.

According to the manufacturer, Rogaine should be applied twice daily. Scalp irritation can occur; dizziness and low blood pressure are less common side effects. The drug is expensive.

Finasteride is an oral prescription medication that inhibits 5-alpha reductase, thereby blocking the conversion of testosterone to DHT. In a 5-mg tablet, finasteride is sold as Proscar, for benign prostatic hyperplasia (see Harvard Men's Health Watch, July 2000); in a 1-mg tablet, it's marketed as Propecia, for male baldness.

To date, only four studies of Propecia, all funded by the manufacturer, have been reported. Two of the trials involved a total of 1,553 men with mild to moderate male pattern baldness that was most prominent at the top of the scalp. Half the men were given Propecia, the other half a placebo. After three months, the men who took Propecia were more satisfied with the appearance of their hair: After a year, they had an average of 876 hairs in a 1-inch circle on the scalp, while those treated with the placebo had 769 hairs.

The third trial evaluated 326 men with mild to moderate frontal hair loss; after a year, 50% of the men taking Propecia and 30% of the men taking the placebo thought their appearance had improved. Finally, a small 2002 study (66 men) reported that finasteride increases hair thickness as well as hair counts, thus enhancing its cosmetic benefit.

The 1,879 men in the three large trials were between the ages of 18 and 41, and none was completely bald. Since Propecia will not revive hair follicles that are inactive, it cannot be expected to regrow hair in older men who are bald. As a result, it warrants consideration only by younger men with partial hair loss.

Because Propecia must be taken daily, years of therapy are required to maintain even modest improvements. Propecia is even more expensive than Rogaine. It is well tolerated, but 1%–2% of men experience diminished libido and potency on Propecia. Because finasteride can produce genital abnormalities in males exposed before birth, the drug should never be taken by women of childbearing age.

To treat or not?
From a medical point of view, there is no need to treat normal hair loss. At best, the treatments are only partially effective, and although they are generally safe, some men may experience side effects. Take a look in the mirror and think it over. And before you decide, try to imagine how Michael Jordan would look with a bit of hair.

Bone Marrow Transplant 2002 Nov;30(9):593-7

Relationship between irreversible alopecia and exposure to cyclophosphamide, thiotepa and carboplatin (CTC) in high-dose chemotherapy.

Reversible alopecia is a commonly observed, important and distressing complication of chemotherapy. Permanent alopecia, however, is rare after standard-dose therapy, but has occasionally been observed after high-dose chemotherapy with cyclophosphamide, thiotepa and carboplatin (CTC). We evaluated the relationships between total exposure to these three compounds and their different metabolites in the high-dose CTC regimen, and the subsequent development of irreversible alopecia. Twenty-four patients received two or three courses of high-dose CTC, each followed by peripheral blood progenitor cell transplantation. Plasma levels of cyclophosphamide, its active metabolite 4-hydroxycyclophosphamide, thiotepa, its active metabolite tepa, and carboplatin were determined, and the area-under-the-plasma concentration-versus-time curves (AUC) of the compounds were calculated. Eight of the 24 patients included in the study developed permanent alopecia, while seven had normal hair regrowth and nine patients developed incomplete and/or thin hair regrowth. The carboplatin AUC and the summed AUC of thiotepa and tepa were both significantly associated with increasing irreversibility of hair loss. These results suggest that high exposure to carboplatin and the sum of the thiotepa and tepa exposure may lead to the development of permanent alopecia. This knowledge could guide therapeutic drug monitoring in order to prevent the occurrence of permanent alopecia and thereby improve the patients' quality of life.

Australas J Dermatol. 2003 Feb;44(1):10-8.

Methods of evaluating hair growth.

For decades, scientists and clinicians have examined methods of measuring scalp hair growth. With the development of drugs that stem or even reverse the miniaturization of androgenetic alopecia, there has been a greater need for reliable, economical and minimally invasive means of measuring hair growth and, specifically, response to therapy. We review the various methods of measurement described to date, their limitations and value to the clinician. In our opinion, the potential of computer-assisted technology in this field is yet to be maximized and the currently available tools are less than ideal. The most valuable means of measurement at the present time are global photography and phototrichogram-based techniques (with digital image analysis) such as the 'TrichoScan'. Subjective scoring systems are also of value in the overall assessment of response to therapy and these are under-utilized and merit further refinement.

Hair Million is a blend of Asian herbs that wards off hair loss and promotes hair growth. Of various approaches to hair restoration, Hair Million offers advantages including low cost compared with other methods or drugs, and safety, as it is made of safe and healthy herbs. For scientifically proven prescription medication, check Propecia.

Related Web resources:

What is hair?

Curly Hair

Biology of hair growth and development.

The phenomenon of hair loss.

Methods and treatments for hair loss and baldness.

Drugs and hair transplantation surgery for hair loss and baldness.

Hair loss linked to other health problems.

Baldness by choice and fashion.

Alopecia info.

Alopecia treatment info.

Hair care info.

Hair loss and alopecia research articles: abstracts and source links.

DHEA has been suggested to provide numerous potential benefits. DHEA (or dehydroepiandrosterone) is converted into androgens (male hormones) or estrogens (female hormones) in the cells.

Herbs and Pharmaceuticals Online|| Best Realtor in Glendale, California: Residential Home and Commercial Property || Related Web pages || Herbs and Pharmaceuticals Online ||