PKA- and PKC-dependent Regulation of Angiopoietin 2 mRNA in Human Granulosa Lutein Cells

Abstract

New blood vessels develop from preexisting vessels in response to growth factors or hypoxic conditions. Recent studies have shown that angiopoietin 2 (ANGPT-2) plays an important role in the modulation of angiogenesis and vasculogenesis in humans and mice. The signaling pathways that lead to the regulation of ANGPT-2 are largely unclear. Here, we report that protein kinase C and protein kinase A activators (ADMB, 8-Cl-cAMP) increased the mRNA levels of ANGPT-2 in human Granulosa cells, whereas PKC and PKA Inhibitors (Rp-cAMP, GÖ 6983) decreased markedly the level of ANGPT-2 mRNA. Due to varying specificity of the modulators for certain protein kinases subunits, we conclude that the conventional PKCs, but not PKC α and β1, the atypical PKCs and the PKA I, are involved in the regulation of ANGPT-2. These findings may help to explain the role of both PKA and PKC dependent signaling cascades in the regulation of ANGPT-2 mRNA.

Key words

Protein kinase - Angiogenesis - ANGPT-2 - Corpus luteum

References

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