The History of Synthetic Testosterone Testosterone has long been banned in sports as a performance-enhancing drug. This use may soon be accepted in medicine alongside other legitimate hormonal therapies (by John M. Hoberman and Charles E. Yesalis ) On June 1, 1889, Charles Edouard Brown-Sequard, a prominent French physiologist, announced at the Societe de Biologie in Paris that he had devised a rejuvenating therapy for the body and mind. The 72-year-old professor reported that he had drastically reversed his own decline by injecting himself with a liquid extract derived from the testicles of dogs and guinea pigs. These injections, he told his audience, had increased his physical strength and intellectual energy, relieved his constipation and even lengthened the arc of his urine.
Almost all experts, including some of Brown-Sequard's contemporaries, have agreed that these positive effects were induced by the power of suggestion, despite Brown-Sequard's claims to the contrary. Yet he was correct in proposing that the functions of the testicles might be enhanced or restored by replacing the substances they produce. His achievement was thus to make the idea of the "internal secretion," initially proposed by another well-known French physiologist, Claude Bernard, in 1855, the basis of an organotherapeutic "replacement" technique. Brown-Sequard's insight that internal secretions could act as physiological regulators (named hormones in 1905) makes him one of the founders of modern endocrinology. So began an era of increasingly sophisticated hormonal treatments that led to the synthesis in 1935 of testosterone, the primary male hormone produced by the testicles.
Since then, testosterone and its primary derivatives, the anabolic-androgenic
steroids, have led a curious double life. Since the 1940s countless elite
athletes and bodybuilders have taken these drugs to increase muscle mass and to
intensify training regimens. For the past 25 years, this practice has been
officially proscribed yet maintained by a $1-billion international black market.
That testosterone products have served many therapeutic roles in legitimate
clinical medicine for an even longer period is less well known. Fifty years ago,
in fact, it appeared as though testosterone might become a common therapy for
aging males, but for various reasons it did not gain this "legitimate"
mass-market status. Perhaps most important, physicians were concerned that these
drugs often caused virilizing side effects when administered to women, including
a huskier voice and hirsutism.
Today, however, there is compelling evidence that these spheres of "legitimate"
and "illegitimate" testosterone use are fusing. Further research into the risks
and the medical value of anabolic-androgenic steroids is under way. Indeed,
scientists are now investigating the severity of such reported temporary
short-term side effects as increased aggression, impaired liver function and
reproductive problems. And some physicians are currently administering
testosterone treatments to growing numbers of aging men to enhance their
physical strength, libido and sense of well-being. Our purpose here is to
describe the largely forgotten history of male hormone therapy that has
culminated in the prospect of testosterone treatments for millions of people.
Organotherapy
Brown-Sequard provided samples of his liquide testiculaire free of charge to
physicians willing to test them. The offer generated a wave of international
experiments aimed at curing a very broad range of disorders, including
tuberculosis, cancer, diabetes, paralysis, gangrene, anemia, arteriosclerosis,
influenza, Addison's disease, hysteria and migraine. This new science of animal
extracts had its roots in a primitive belief that came to be known as similia
similibus, or treating an organ with itself. Over many centuries since ancient
times, physicians had prescribed the ingestion of human or animal heart tissue
to produce courage, brain matter to cure idiocy and an unappetizing array of
other body parts and secretions--including bile, blood, bone, feces, feathers,
horns, intestine, placenta and teeth--to ameliorate sundry ailments.
Sexual organs and their secretions held a prominent place in this bizarre
therapeutic gallery. The ancient Egyptians accorded medicinal powers to the
testicles, and the Roman scholar Pliny the Elder reports that the oil-soaked
penis of a donkey or the honey-covered penis of a hyena served as sexual
fetishes. The "Ayurveda of Susruta" (circa 1000 B.C.) recommended the ingestion
of testis tissue as a treatment for impotence. Johannes Mesue the Elder (A.D.
777-857) prescribed a kind of testicular extract as an aphrodisiac. The "Pharmacopoea
Wirtenbergica," a compendium of remedies published in 1754 in Germany, mentions
horse testicles and the phalluses of marine animals. These therapeutic exotica
are significant because they dramatize the impossibility, for ancients and
moderns alike, of separating sexual myth from sexual biology.
Two of the researchers inspired by Brown-Sequard's work were the Austrian
physiologist Oskar Zoth and his compatriot Fritz Pregl, a physician who
eventually turned to analytic chemistry and received a Nobel Prize in 1923. When
sports physiology was in its infancy, these men investigated whether testicular
extracts could increase muscle strength and possibly improve athletic
performance. They injected themselves with a liquid extract of bull's testicles
and then measured the strength of their middle fingers. A Mosso ergograph
recorded the "fatigue curve" of each series of exercises.
Zoth's 1896 paper concluded that the "orchitic" extract had improved both
muscular strength and the condition of the "neuromuscular apparatus." Most
scientists now would say these were placebo effects, a possibility these
experimenters considered and rejected. Yet the final sentence of this
paper--"The training of athletes offers an opportunity for further research in
this area and for a practical assessment of our experimental results"--can lay
claim to a certain historical significance as the first proposal to inject
athletes with a hormonal substance.
The growing popularity of male extracts prompted other scientists to search for
their active ingredient. In 1891 the Russian chemist Alexander von Poehl singled
out spermine phosphate crystals, first observed in human semen by the
microscopist Anton van Leeuwenhoek in 1677 and again by European scientists in
the 1860s and 1870s. Poehl claimed correctly that spermine occurs in both male
and female tissues, and he concluded that it increased alkalinity in the
bloodstream, thereby raising the blood's capacity to transport oxygen.
This was an interesting observation insofar as hemoglobin does pick up oxygen in
a slightly alkaline environment and releases it when the pH is slightly acidic.
But he was incorrect in that no chemical mediates the binding of oxygen to
hemoglobin. Still, Poehl believed he had improved on Brown-Sequard's work, for
if spermine did accelerate oxygen transport, then it could claim status as a "dynamogenic"
substance, having unlimited potential to enhance the vitality of the human
organism. As it turned out, spermine's function remained unknown until 1992,
when Ahsan U. Khan of Harvard Medical School and his colleagues proposed that it
helps to protect DNA against the harmful effects of molecular oxygen.