Levels of MMP₂, TIMP₁ and TIMP₂ in Follicular Fluids in Women Undergoing in Vitro Fertilization and Their Relationship to Oocyte Quality

Recently, the important role of matrix metalloproteinases (MMPs) has been identified in follicular development and subsequent ovulation. Although the role of MMP in ovarian tissue remodeling during folliculogenesis has been well studied, the relationship between matrix protease activity and their inhibitors - Tisue inhibitors of matrix metalloproteinases (TIMP) and aging of the oocytes is still unclear. The present study aimed to establish the probable relationship between the expression levels of MMP-2 and TMP-1 and TIMP-2 in follicular fluid with the degree of oocyte maturity and quality. Follicular fluids from 20 women collected on the day of follicular puncture were tested for the presence of MMP-2, TIMP-1, and TIMP-2 using enzyme-linked immunosorbent assay (ELISA). The oocytes obtained were described in terms of maturity, morphology, and fertilization, as well as the embryo’s quality and rate of development. MMP-2 was significantly higher in follicular aspirates in the first prophase of meiosis - germinal vesicle (GV), compared to aspirates with first metaphase (MI) (p=0.011) and second metaphase (MII) of mature oocytes (p=0.010). The MMP-2/TIMP-1 ratio was significantly higher for GV compared to M1 (p=0.011), M2 (p=0.006) and atretic oocytes (p=0.032); (F(3, 71)=2.909, p=0.040). Based on our results, we can conclude that MMP-2 concentration in follicular fluids during the IVF / ICSI procedure had a significant relationship to oocyte maturation levels. It was significantly higher in the case of immature oocytes. On the other hand, oocytes with normal morphology were associated with a significantly higher MMP-2 concentration in follicular fluids.