Transforming growth factor beta1 regulates follistatin mrna expression during in vitro bovine granulosa cell differentiation

FAZZINI M; VALLEJO G; COLMAN-LERNER A; TRIGO R; CAMPO S; BARAÑAO LS; SARAGUETA PE

Journal of Cell Physiology

Año: 2006 p. 40 - 48

In order to test the hypothesis that transforming growth factor b (TGF-b) acts by FS regulation on bovine granulosa cells in in vitro differentiation, we analyzed the effect of TGF-b1 on follistatin mRNA expression in three differentiation states of bovine granulosa cells. We showed a positive regulation of FS mRNA after TGF-b1 (1 ng/ml) treatment of freshly isolated granulosa cells from small-medium antral follicles (2–8 mm). This effect was abolished by the addition of exogenous follistatin (100 ng/ml), suggesting that this effect could be mediated by activin. Although these cells showed a similar effect on FS mRNA expression after treatment with activin-A, a soluble form of activin receptor type IIA was unable to inactivate the TGF-b effect. When we tested the TGF-b effect on FS mRNA in different granulosa cell states, TGF-b1 regulation was associated with progesterone production only in freshly isolated cells. The amount of total activin-A produced by first passage cells (dedifferentiated cells), was ten times smaller than the one measured in a conditioned medium from freshly isolated cells (mature cells). The TGF-b1-dependent FS mRNAexpression persisted in first passage cells without changes with FS addition. On the other hand, the BGC-1 granulosa cell line (immature cells) produced large amounts of activin-A regulated by TGF-b1 and an invariable steady state of FS mRNAs. In summary, our results showed that FS mRNA expression is regulated by TGF-b1 independently of activin effects in differentiated granulosa cells. J. Cell. Physiol. 207: 40–48, 2006.
2005 Wiley-Liss, Inc.b (TGF-b) acts by FS regulation on bovine granulosa cells in in vitro differentiation, we analyzed the effect of TGF-b1 on follistatin mRNA expression in three differentiation states of bovine granulosa cells. We showed a positive regulation of FS mRNA after TGF-b1 (1 ng/ml) treatment of freshly isolated granulosa cells from small-medium antral follicles (2–8 mm). This effect was abolished by the addition of exogenous follistatin (100 ng/ml), suggesting that this effect could be mediated by activin. Although these cells showed a similar effect on FS mRNA expression after treatment with activin-A, a soluble form of activin receptor type IIA was unable to inactivate the TGF-b effect. When we tested the TGF-b effect on FS mRNA in different granulosa cell states, TGF-b1 regulation was associated with progesterone production only in freshly isolated cells. The amount of total activin-A produced by first passage cells (dedifferentiated cells), was ten times smaller than the one measured in a conditioned medium from freshly isolated cells (mature cells). The TGF-b1-dependent FS mRNAexpression persisted in first passage cells without changes with FS addition. On the other hand, the BGC-1 granulosa cell line (immature cells) produced large amounts of activin-A regulated by TGF-b1 and an invariable steady state of FS mRNAs. In summary, our results showed that FS mRNA expression is regulated by TGF-b1 independently of activin effects in differentiated granulosa cells. J. Cell. Physiol. 207: 40–48, 2006.
2005 Wiley-Liss, Inc.b effect. When we tested the TGF-b effect on FS mRNA in different granulosa cell states, TGF-b1 regulation was associated with progesterone production only in freshly isolated cells. The amount of total activin-A produced by first passage cells (dedifferentiated cells), was ten times smaller than the one measured in a conditioned medium from freshly isolated cells (mature cells). The TGF-b1-dependent FS mRNAexpression persisted in first passage cells without changes with FS addition. On the other hand, the BGC-1 granulosa cell line (immature cells) produced large amounts of activin-A regulated by TGF-b1 and an invariable steady state of FS mRNAs. In summary, our results showed that FS mRNA expression is regulated by TGF-b1 independently of activin effects in differentiated granulosa cells. J. Cell. Physiol. 207: 40–48, 2006.
2005 Wiley-Liss, Inc.
2005 Wiley-Liss, Inc.