ScienceDaily (Apr. 22, 2008) — The production of the sex hormones testosterone, progesterone, and estrogen is controlled by two other hormones, which are known as luteinizing hormone (LH) and follicle stimulating hormone (FSH).

Disturbances in the levels of either LH or FSH affect the production of sex hormones and can cause either premature or delayed puberty as well as infertility. New data, generated in mice by Jacques Baenziger and colleagues, at Washington University School of Medicine, St. Louis, have identified a new mechanism by which levels of LH in the blood are regulated.

Attached to LH are unique carbohydrate structures that end in a carbohydrate unit known as GalNAc-4-SO4. In the study, mice lacking the protein responsible for adding GalNAc-4-SO4 to the end of the carbohydrates on LH were found to have higher levels of LH in the blood than normal mice.

In male mice this caused increased levels of testosterone and premature sexual development. In female mice this caused increased levels of estrogen, premature sexual development, and increased fertility.

Thus, the authors concluded that the unique carbohydrate structures attached to LH have a crucial role in regulating the levels of this hormone in the blood.