17β-estradiol and cathepsins control primordial follicle growth in mouse ovaries

This study aimed to clarify the physiological mechanism regulating the growth of primordial follicles in mouse ovaries. In a previous study, we found that increasing the fetal bovine serum concentration in the culture medium promoted the growth of primordial follicles in cultured postnatal day 0 ovaries but not in cultured postnatal day 4 ovaries. Based on these results, we hypothesized that the regulatory system repressing the growth of primordial follicles is established in postnatal day 4 ovaries. To confirm this hypothesis, microarray analysis of postnatal day 0 and 4 ovaries was performed. The results revealed that the expression of mRNA of stefin A homologs increased in postnatal day 4 ovaries. Stefin A belonging to the type 1 cystatin superfamily is an inhibitor of cysteine cathepsins. Consistently, the inhibitor of cathepsins repressed the growth of primordial follicles in cultured postnatal day 0 ovaries. Furthermore, we found that 17β-estradiol promoted the expression of mRNA of stefin A homologs in cultured ovaries and repressed the growth of primordial follicles. Our results demonstrate that 17β-estradiol and cathepsins regulate the growth of primordial follicles in mouse ovaries.

INVESTIGATING COOLING RATE AND FETAL BOVINE SERUM CONCENTRATION ON SURVIVAL AND STEMNESS OF MESENCHYMAL STEM CELLS AFTER CRYOPRESERVATION

Mesenchymal stem cells (MSCs) can be derived from many different sources. Umbilical cord blood is a rich source of MSCs. The cryopreservation of MSCs that MSCs are still alive and differentiate into many different kinds of functional cells is very important. The aims of this research are to identify ratio of alive and dead cells as well as stemness of them after thaw. The results showed that the stemness was not affected by cryopreservative protocols or media. All cells being alive after thaw could form colonies and differentiate into adipocytes and osteoblasts. Ratio of alive and dead cells was affected very much by cryopreservative protocols and media.