In vitro evidence suggests activin-A may promote tissue remodeling associated with human luteolysis

Luteolysis in women is associated with an up-regulation of the expression and activity of matrix metalloproteinase- 2 (MMP2), which is inhibited by human chorionic gonadotropin (hCG) during maternal recognition of pregnancy. Because the primary source of MMP-2 is fibroblasts that do not express LH/hCG receptors, we aimed to investigate the regulation of MMP-2. Women with regular cycles having hysterectomy for nonmalignant conditions and women undergoing oocyte retrieval for assisted conception were used in this current study. Novel primary cultures and cocultures of luteinized granulosa cells and fibroblast-like cells in conjunction with human corpora lutea from different stages of the luteal phase were used to investigate the role of activin- A in the corpus luteum. The effect of hCG, activin- A, and follistatin on MMP-2 activity and expression was assessed by gelatin zymography and quantitative RT-PCR in primary cell cultures. Confirmation