Synergistic roles of bone morphogenetic protein 15 and growth differentiation factor 9 in ovarian function.

Knockout mouse technology has been used over the last decade to define the essential roles of ovarian-expressed genes and uncover genetic interactions. In particular, we have used this technology to study the function of multiple members of the transforming growth factor-beta superfamily including inhibins, activins, and growth differentiation factor 9 (GDF-9 or Gdf9). Knockout mice lacking GDF-9 are infertile due to a block in folliculogenesis at the primary follicle stage. In addition, recombinant GDF-9 regulates multiple cumulus granulosa cell functions in the periovulatory period including hyaluronic acid synthesis and cumulus expansion. We have also cloned an oocyte-specific homolog of GDF-9 from mice and humans, which is termed bone morphogenetic protein 15 (BMP-15 or Bmp15). To define the function of BMP-15 in mice, we generated embryonic stem cells and knockout mice, which have a null mutation in this X-linked gene. Male chimeric and Bmp15 null mice are normal and fertile. In contrast to Bmp15 null males and Gdf9 knockout females, Bmp15 null females (Bmp15(-/-)) are subfertile and usually have minimal ovarian histopathological defects, but demonstrate decreased ovulation and fertilization rates. To further decipher possible direct or indirect genetic interactions between GDF-9 and BMP-15, we have generated double mutant mice lacking one or both alleles of these related homologs. Double homozygote females (Bmp15(-/-)Gdf9(-/-)) display oocyte loss and cysts and resemble Gdf9(-/-) mutants. In contrast, Bmp15(-/-)Gdf9(+/-) female mice have more severe fertility defects than Bmp15(-/-) females, which appear to be due to abnormalities in ovarian folliculogenesis, cumulus cell physiology, and fertilization. Thus, the dosage of intact Bmp15 and Gdf9 alleles directly influences the destiny of the oocyte during folliculogenesis and in the periovulatory period. These studies have important implications for human fertility control and the maintenance of fertility and normal ovarian physiology.

The bone morphogenetic protein 15 gene is X-linked and expressed in oocytes.

We have taken advantage of the sequence relationships among the bone morphogenetic proteins (BMPs) to identify the mouse Bmp15 and human BMP15 genes. The 392-amino acid prepropeptides encoded by these BMP genes exhibit significant homology to each other, although the 70% identity observed between the 125-amino acid mature peptides is considerably lower than that seen in comparisons of other mouse and human orthologs. Both genes share a common structural organization and encode mature peptides that lack the cysteine residue normally involved in the formation of a covalent dimer. In addition, mouse Bmp15 and human BMP15 map to conserved syntenic regions on the X chromosome. We demonstrate, through a combination of Northern blot and in situ hybridization analyses, that mouse Bmp15 is expressed specifically in the oocyte beginning at the one-layer primary follicle stage and continuing through ovulation. Interestingly, BMP-15 is most closely related to and shares a coincident expression pattern with the mouse growth/differentiation factor 9 (GDF-9) gene that is essential for female fertility. Our findings will be important for defining the role of BMP-15 in follicular development.

Ectopic induction of tendon and ligament in rats by growth and differentiation factors 5, 6, and 7, members of the TGF-beta gene family.

Little is known about the regulatory signals involved in tendon and ligament formation, and this lack of understanding has hindered attempts to develop biologically based therapies for tendon and ligament repair. Here we report that growth and differentiation factors (GDFs) 5, 6, and 7, members of the TGF-beta gene superfamily that are most related to the bone morphogenetic proteins, induce neotendon/ligament formation when implanted at ectopic sites in vivo. Analysis of tissue induced by GDF-5, 6, or 7, containing implants by currently available morphological and molecular criteria used to characterize tendon and ligament, adds further evidence to the idea that these GDFs act as signaling molecules during embryonic tendon/ligament formation. In addition, comparative in situ localizations of the GDF-5, 6, and 7 mRNAs suggest that these molecules are important regulatory components of synovial joint morphogenesis.

Reference values for the oral glucose tolerance test at each trimester of pregnancy.

A 100-gram oral glucose tolerance test (OGTT) was performed on a selected group of normal women at each trimester of pregnancy to establish reference values for hyperglycemia and hypoglycemia. Ninety three OGTT were performed in the first trimester, 121 in the second trimester, and 98 in the last trimester. The fasting serum glucose did not differ significantly between the trimesters. The values at 60 and 120 minutes were significantly different for the fifth, fiftieth, and ninety-fifth percentiles between each trimester of pregnancy. For the 180-minute readings, the fifth and fiftieth percentiles were not significantly different between the first and second trimester of pregnancy, but the results of the third trimester were significantly higher than those of the other trimesters. The mean fasting insulinemia remained relatively constant during pregnancy. Insulin response to OGTT increased during the progression of the pregnancy. The interpretation of the glucose tolerance tests during pregnancy, either to detect gestational diabetes or hypoglycemia, should take these physiologic changes into account.

Treatment of Hemophilus vaginalis vaginitis.

Four antimicrobial agents (triple sulfa cream, doxycycline, ampicillin, and metronidazole) were studied by double-blind techniques to determine their effectiveness in the treatment of Hemophilus vaginalis vaginitis, documented by vaginal culture in 96 patients. Cure was confirmed by negative vaginal cultures 7 weeks after the start of therapy. Metronidazole proved to be effective in 20 of 22 couples (90.9%) treated. Sulfa cream, doxycycline, and ampicillin were effective in 47.8 to 63.6% of patients treated.