From Arnold Berthold in 1849 that worked on Capons, and discovered the effect of testis in birds, to Charles-Édouard Brown-Séquard and Thomas Addison who worked on the elixir which was a combination of blood from the testicular veins, semen, and juice extracted from the testicles which were crushed immediately after it was extracted from a guinea pig or a dog. This was known as the Brown-Séquard elixir which was believed to have rejuvenated him but was not reproducible with other scientific tests but led to the experiment on hormones. I discussed Victor Horsley, and George Oliver in my previous post, and they were frontrunners in the discovery of hormones. let's continue without wasting any time.
The next breakthrough in the hormone journey was as a result of women who were undergoing oophorectomy where their both ovaries were removed to prevent disabilities in women (so they thought since it was believed that the nervous system controlled all parts of the body and it was believed that the ovaries were taking most of the resources that should go to other parts of the body). This didn't come without complications as women start to experience signs of menopause. This led to numerous research to understand why this was happening and then Josef Halban was the scientist that proved that glands didn't communicate through nerves. He transplanted the ovaries of women and transplanted under the skin of a guinea pig, and they showed changes so he agreed that the changes are by internal secretion which goes around affecting the distal point. This led to the definition of the endocrine system discrediting the long belief that ovaries were communicating with the nervous system through nerves.
At a University dinner in Cambridge, Ernest Starling coined the name hormone. The hormone is a fundamental part of every multicellular organism plant or animals use hormones, and humans have about 50 hormones in our body, with hormones for stress Cortisol, flight and fight hormone adrenaline, Oxytocin hormone for bonding, and so on. Different hormones have different molecular structures and are sent to a particular target cell region. They go through the bloodstream to their destination location, acting on their target cells and making them work according to their specifics. For instance, when the adrenaline gets to the heart, it makes it pump faster, and harder but this is for a short time. At the same time, hormones like estrogen have a lifelong effect on the heart. Not all hormones are to function for a long time, and not all hormones are to be released at all times. For instance, when there is an oversecretion of the growth hormone, it can lead to acromegalic gigantism. The pituitary gland in the base of the brain is responsible for releasing this growth hormone, a tumor in the pituitary gland can cause an abnormal secretion of the growth hormone, similar to what Harvey Cushing discovered with Charles burns skull who had gigantism.
One hormone that we are always hearing about in all parts of the world is the Insulin hormone, and without this hormone, you are at a high risk of developing diabetes. While diabetes is treatable currently, before the discovery of insulin, it was not treatable and a lot of people died from it. Insulin allows sugar to be absorbed as energy(ATP) but when it is not present, the sugar is present in the blood and is passed out through the urine. A lot of children suffer from diabetes Mellitus and their urine has a sweet taste as they cannot store energy. While it was proven in the late 19th century that the pancreas was responsible for diabetes, finding a solution was a big problem. They were able to identify that a dysfunction in the pancreas will lead to a rise in the blood sugar level of the body but there was no way to identify a solution to the condition. The pancreas is responsible for producing digestive juice through the pancreatic duct, as well as producing insulin for balancing blood sugar levels. Scientists had a tough time removing the pancreas and putting it into another person as most time what will be present is the pancreatic juice and not the insulin, so that method wasn't going to suffice. Sir Frederick G Banting was able to find the cure for diabetes. he didn't find the cure in a lab, he was giving lectures to pay up for his debt. When preparing for a lecture, he found an article "Surgery, Gynecology, and Obstetrics" which looked into destroying the digestive enzyme of the pancreas while leaving the hormone-producing cells to function. He was going to operate on dogs and tie the pancreatic duct in the dogs, keeping the pancreas alive but with no pancreatic duct as the ducts were dead while the pancreas only produced insulin. When he tried the insulin extracts on dogs, they worked perfectly, so it was time to test them on humans. Leonard Thompson was the first to be treated with Banting's insulin extract, and it was a success. Currently, it is produced synthetically, and it has been a miracle dose.
With this success, scientist Eugen Steinach started to look at how he could bring back the agility of the youth to the age, in a way to make them more youth-like and not old. He was working on eternal youth and decided to use Banting's procedure in a different way which in his case was tying the sperm duct to enable an increase in the production of testosterone hormone but he didn't put into consideration the pituitary hormone which is responsible for homeostasis although producing the growth hormone. It was responsible for making sure that hormones were not available in excess or too less, and with Steinach, there was no chance his theory was going to work. It worked with Banting's because there was no insulin present in the pancreas.
One last thing. Do you know that fat can produce hormones? not all hormones are from a gland, fat cells can produce the hormone called leptin which is secreted into the bloodstream and find its way to the brain, signaling that the amount of food being consumed is enough, thereby causing loss of appetite.
One question before we go. Do you think that hormones can be scientists' new breakthrough for longevity in the future?