A recent study has found that silibinin extracted from the seeds of the milk thistle could be a new, non-invasive treatment for Cushing Disease. This condition (not to be confused with Cushing’s Syndrome) is caused when a tumor forms on the brain’s pituitary gland.
This tumor secretes stress hormone, which causes cortisol to be released from the adrenal glands. This results in symptoms such as rapid weight gain, muscular weakness, and higher blood pressure. Patients may also develop depression, cognitive dysfunction, or osteoporosis, as well as becoming more susceptible to infection.
While between 80 and 85 percent of these tumors can be removed with brain surgery. For inoperable cases, the treatment’s side effect of hyperglycemia is almost as intense as the tumor itself.
A group of researchers from the Max Planck Institute of Psychiatry has discovered that silibinin extracted from milk thistle may provide a non-invasive treatment for Cushing Disease. This compound is already used to treat liver poisoning and liver disease, and has been proven safe for use in humans.
After testing the extract on human tumor tissue, the researchers discovered that the tumor cell growth slowed, stress hormone production returned to normal, and the symptoms of Cushing Disease ceased in mice.
According to the study’s lead scientist Marcelo Paez-Pereda, the researchers decided to test silibinin after examining what would cause the overproduction of adrenocorticotropin (ACTH), the stress hormone produced in Cushing Disease.
Initial experiments found that patients with Cushing Disease produced extremely high amounts of the heat shock protein 90. These proteins stick to the glucocorticoid receptors that inhibit ACTH production. Silibinin binds to the heat shock protein 90, allowing the glucocorticoid receptors to work normally.
Researchers now believe this treatment may be effective not only for Cushing Disease, but for other conditions involving these receptors, such as acute lymphoblastic leukemia, multiple myeloma, and lung tumors.