Testosterone and the Death of Brain Cells
I’m sure that you’ve heard the Robin Williams joke, “See, the problem is that God gives men a brain and a penis, and only enough blood to run one at a time.”
Well it may turn out that Robin was right for the wrong reason.
Typically thought of as the “male hormone,” testosterone plays key roles in maintaining health and wellness in both men and women. It is true that most men produce about twenty ties as much testosterone as women, but in both sexes, it is involved in energy, libido, and immune function and helps protect against osteoporosis. It is also essential for the normal development, growth and functioning of the brain. In small amounts it may also be neuroprotective.
However, too much of a good thing can quickly turn bad. Researchers from the Departments of Pharmacology and Cellular and Molecular Physiology at Yale University in New Haven, Connecticut have just published an important study of apoptosis or programmed cell death in neurons exposed to excessive amounts of testosterone. Apoptosis is a process for disposing of un-needed or unwanted cells, but if it gets out of control, it can begin to remove cells that should have been left alone. Apoptosis is thought to pay a role in illnesses including Alzheimer’s disease and schizophrenia.
While too much testosterone destroyed nerve cells, estrogen appeared to be neuroprotective: there was less cell death in the presence of the hormone.
This new finding has a number of important practical implications.
Testosterone is one of the hormones abused by some athletes. It certainly can enable them to pump up their muscles, but it may also make them aggressive. Now we know that the practice may also kill neurons. And loss of brain cells is associated with a loss of brain function. This is yet another reason why people should think long and hard before they try to use testosterone supplements. The concentrations used in the experiments were very close to what we might expect to see in someone supplementing with the hormone.
These effects of testosterone on neurons will likely have long term effects on brain function. Though you do generate new connections and some new neurons throughout life, there is a limit to how many you can put back, once they’ve been tainted by testosterone.
And since this is election year here in the United States, I’m sure that we’re now going to have to have a string of off-color jokes about the esteemed Governor of California….