A selective estrogen receptor modulator, also known as a SERM, is a compound that acts on hormone receptors that are activated by 17β-estradiol, more commonly referred to as estrogen. Selective estrogen receptor modulators are active in many different tissues throughout the body, allowing them to moderate the effects of estrogen on a large scale. In some cases, a selective estrogen receptor modulator may act as an agonist, a compound that triggers some biological response by binding to a receptor. In other cases, a selective estrogen receptor modulator acts as an antagonist, a molecule that suppresses a response by binding to a receptor. Selective estrogen receptor molecules can act as either agonists or antagonists depending on the particular kind of tissue in which they are found.
Estrogens are very important compounds that function most notably as female sex hormones. They function in diverse roles, ranging from the maintenance of mental health to the balance of water, sodium, and other substances in the body. Though it is necessary for the maintenance of health, estrogen imbalances can also lead to health problems, such as breast cancer and osteoporosis. Many forms of breast cancer rely on a steady supply of estrogen to grow and to spread, and osteoporosis is generally caused by estrogen deficiency. It is not uncommon to treat both of these conditions through the use of a selective estrogen receptor modulator.
Tamoxifen, for example, is a selective estrogen receptor modulator that functions as an antagonist of the estrogen receptors in breast tissue. Treatment with tamoxifen, then, can greatly slow the progression of estrogen receptor-positive forms of breast cancer, which grow quickly with a supply of estrogen. It does so by blocking the receptor sites in breast tissue that would normally be activated by estrogen. Tamoxifen also has a beneficial side-effect: it acts as an agonist in bone tissue. It can be used to fight osteoporosis because its agonistic qualities promote an increase in bone density.
Using a selective estrogen receptor modulator in treatment can lead to some negative effects because they can act as agonists or as antagonists in different parts of the body. While a certain selective estrogen receptor modulator may prevent one kind of cancer, it may in turn promote another. They may also have a destabilizing effect on one's mental health because they affect the amount of estrogen present throughout the body, and estrogen is very important in the maintenance of mental health.
