Effects of Selenium and Mistletoe Extracts on the Expression of Angiogenic Growth Factors and Sprout Formation in a Spheroid Cell Culture System of Human Granulosa Lutein Cells

Abstract

The corpus luteum provides an outstanding model to study the regulation of angiogenic processes, which are critical for normal tissue growth, development, and function. After ovulation, the corpus luteum is built from avascular granulosa cells through rapid vascularisation. This process is regulated by the vascular endothelial growth factors (VEGF). Both, sprouting of endothelial and sprouting of granulosa cells are frequently observed during the formation of an active corpus luteum. Recent data demonstrate that angiogenesis in various tissues may be influenced by selenium and mistletoe extracts. In the present study, we investigated the effects of selenium and mistletoe extracts on mRNA levels of VEGF‐A and ANGPT2 by real-time PCR in human granulosa cells. In addition, the impact on sprout formation in a spheroid cell culture system was determined. Our experiments presented evidence that mistletoe extracts inhibit the expression of VEGF‐A in granulosa cells but ANGPT-2 and stimulation of granulosa cells with selenium inhibited the expression of ANGPT2.

Zusammenfassung

Das Corpus luteum ist ein geeignetes Modell zum Studium angiogenetischer Prozesse. Nach der Ovulation kommt es zu einer massiven Angiogenese. Dieser Vorgang wird durch die Expression und Sekretion von Wachstumsfaktoren reguliert. Unter den Wachstumsfaktoren kommt dem VEGF und den Angiopoietinen eine besondere Bedeutung zu. Jüngste Untersuchungen zeigen, dass Selen und Mistelextrakt einen Einfluss auf angiogenetische Vorgänge haben. In der vorliegenden Studie untersuchen wir den Einfluss von Selen und Mistelextrakt auf auf die Expression von Angiogenesefaktoren in menschlichen Granulosazellen. Darüber hinaus wird der Einfluss dieser Substanzen auf die Angiogenese im Sphäroidmodell getestet. Die Ergebnisse der Arbeit weisen darauf hin, dass sowohl Selen als auch Mistelextrakt einen Einfluss auf die angiogenetischen Prozesse menschlicher Granulosa-Zellen besitzen.

Key words

angiogenesis - granulosa‐lutein‐cells - mistletoe extract - selenium

Schlüsselwörter

Angiogenese - Granulosa‐Lutein‐Zellen - Mistelextrakt - Selen

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