According to UCSF Professor Michael German, MD, who is also the senior author of the paper, tryptophan hydroxylase (Tph1), the enzyme that produces serotonin from tryptophan increased by as much 1000-fold during the early pregnancy. The researchers found that inhibition of serotonin synthesis by restricting the intake of tryptophan in pregnant mice blocked beta cell proliferation and resulted in the development of glucose intolerance and gestational diabetes in the mice.
The research indicates that anything that affects the production of serotonin, such as drugs, diet or genetic inheritance may affect the risk of developing gestational diabetes and possibly the long-term risk of developing type 2 diabetes.
Serotonin has been widely studied as a neurotransmitter in the brain for its effects on appetite and mood, especially depression. Since it also influences the insulin production, this could explain why some patients with gestational diabetes experience depression. This would also explain the effect of some classes of psychiatric medications on diabetes.
The study will be published in the upcoming issue of “Nature Medicine” and was published online on June 27, 2010.More