JCI table of contents: April 22, 2008

View the PDF of this article at: https://www.the-jci.org/article.php?id=34149

REPRODUCTIVE BIOLOGY: How is a regulator of sex hormone production regulated itself?

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.

TITLE: Ablation of GalNAc-4-sulfotranferase-1 enhances reproduction by altering the carbohydrate structures of luteinizing hormone in mice

AUTHOR CONTACT:
Jacques U. Baenziger
Washington University School of Medicine, St. Louis, Missouri, USA.
Phone: (314) 362-8730; Fax: (314) 362-8888; E-mail: .

View the PDF of this article at: https://www.the-jci.org/article.php?id=32467

ONCOLOGY: Filling in the blanks: defining a molecular pathway that promotes inflammation and tumor development in the stomach

Persistent infection with the bacterium Helicobacter pylori leads to persistent inflammation of the stomach lining and in some individuals stomach cancer, also known as gastric cancer. New insight into some of the molecules and signaling pathways that might promote inflammation and tumor development in the stomach has been provided by a team of researchers in Australia, at the Royal Melbourne Hospital and Monash University, through their analysis of a mouse model of gastric cancer. Specifically, it was shown that the soluble factor IL-11 was responsible for promoting inflammation and tumor development in these mice through activation of the signaling molecules Stat3 and, to a lesser extent, Stat1. Further, the activation of Stat3 and Stat1 was found to induce the expression of more IL-11, generating an amplification effect. The importance of these observations is discussed in detail in an accompanying commentary by Juanita Merchant, at the University of Michigan, Ann Arbor.

TITLE: STAT3 and STAT1 mediate IL-11–dependent and inflammation-associated gastric tumorigenesis in gp130 receptor mutant mice