The fantastical world of hormones.

Professor John Wass, Oxford University, introduces us to the world of hormones; demonstrating how they shape each and every one of us; from our height and weight to how we feel and behave. Professor Wass asserts that to a greater or lesser extent, they control everything in your body. Hormones are now at the forefront of medical research as we discover that the effects of hormones are more widespread. Chronologically, our understanding of hormones is relatively recent. Woss begins the journey about hormones by playing a piece of opera from 1902, performed by a grown man, singing in an usually high voice. The singer Farinelli (18th century) was able to sing soprano; due to being a castrato (an adolescent who was castrated before puberty). Woss points out other permanent visible effects of castration from Farinelli’s portrait: from a straight hair line similar to a woman to a lack of an Adam’s apple. There was, however, no scientific evidence for this change until the 19th century. In 1849, the German physiologist Arnold Berthold experimented on chickens – this uncovered the mechanism explaining how castration affects the body. Professor Saffron Whitehead, St. George’s, explains how Berthold attempted to reverse the changes that been caused by castration by transplanting the testes into the abdomen. During the autopsy, Berthold discovered that blood vessels had reattached themselves onto the testes as well as grown around them; Berthold deduced that whatever changes in the body the testes caused, it was done through the blood. We now know that Berthold was seeing the action of testosterone. It wasn’t until the 20th century that scientists acknowledged that Berthold had been the first to discover how the testes work. Throughout the 1890s, there was a genuine breakthrough of scientific discovery; vital to modern endocrinology. Two British doctors from the 1890s were the first to use hormones to cure thyroid disorders; Victor Horsley, an advocate of free health care, and George Redmayne Murray (Horsley’s student). He had a solution to the problems of Horsley’s original surgical treatment, to create pink thyroid juice. Thyroid hormones, in contrast to testosterone, last several days in the blood; hence the injections worked. Woss visits the oldest operating theatre in England, where he describes how ovaries were often removed from women suffering from anxiety, hysteria, anorexia and nymphomania. Professor Whitehead speaks of how it was believed that ovaries were the source of physical and mental disabilities. This was caused by a misconception that glands were connected via the nervous system, instead of blood. It was discovered that the ovaries were not controlling physiology through nerves, but by secretions; chemical messengers which move around the body in the blood, creating a new system; the endocrine system. Woss asserts that every form of life that has more than one cell, uses hormones; with more than 80 known hormones in humans. Despite different molecular structures, what unites hormones is how they work. Woss meets with a former patient, Chris Greener, who stands at 75 which was caused by an over production of growth hormone. In the 1780s, Irishmen Charles Byrne, standing at 77 attracted attention of John Hunter who displayed his skeleton in a museum. In 1909, Harvey Cushing attempted to explain why Byrne grew so tall and pointed out a tiny gland that’s hidden in the base of the brain, known as the pituitary gland. Dr Suzy Lishman, Peterborough City Hospital demonstrates the difficulty of finding the pituitary gland. The pituitary gland typically rests in between a protective layer of bone, but in the case of Charles Byrne this protection was not visible, so Cushing deduced that this is what caused the excess growth. John Woss goes on to describe what can typically be referred to as the most well-known hormones, insulin, without which one would develop diabetes. Prior to the discovery of insulin, diabetes would result in death, but researchers discovered that the pancreas might be at the cause of the disease. Professor Whitehead describes how two German physiologists at the start of the 19th century removed the pancreas from dogs and observed that they developed diabetes. Frederick Banting was the first doctor to receive a Nobel prize in medicine due to an endocrinology discovery of using insulin on humans. This opened a new wave of hormonal research in the 1920s. Ross describes how in Vienna, the idea of cutting off testosterone, believing that this would create more room for hormone producing cells in the testes. Ross describes this as a scientific blind alley. It was later discovered that the pituitary gland also plays the role of mediator and can control levels of hormones in order to regulate them. Ross meets Professor Sadaf Farooqi, University of Cambridge who outlines the discovery of a new hormone called leptin produced by fat (not a gland). Leptin typically tells the host if they are full, but in some cases, leptin is not sufficiently produced which can cause obesity. Ross believes that in the future, many more hormones, along with treatments and eventually cures will be discovered.