Effects of Recombinant Human FSH and hCG on the Expression of Interleukin-6 (IL-6) and Vascular Endothelial Growth Factor-A (VEGF-A) in Human Granulosa Lutein Cells and Stimulation of VEGF-A Expression by IL-6

Zusammenfassung

Einleitung

In der vorliegenden Studie wurde der Einfluss von Gonadotropinen auf die VEGF- und IL-6-Sekretion menschlicher Granulosazellen untersucht sowie der Einfluss von IL-6 auf die VEGF-Sekretion.

Methoden

Granulosazellen wurden aus der Follikelflüssigkeit von Patientinnen im Zusammenhang mit einer IVF-Behandlung gewonnen. Nach Stimulation der Zellen mit verschiedenen FSH- und hCG-Konzentrationen wurden die VEGF- und IL-6-Expressionen im Northern Blot gemessen. Die Bestimmung der VEGF- und IL-6-Proteinsekretion im Zellüberstand erfolgte durch ELISA. Die Zellen wurden darüber hinaus mit ansteigenden IL-6-Konzentrationen inkubiert und anschließend wurden die VEGF-A-Expression und ‐Sekretion ermittelt.

Ergebnisse

Die Stimulation von Granulosazellen sowohl mit rhFSH als auch mit hCG führte zu einer dosisabhängigen Steigerung der VEGF- und IL-6-Sekretion. Die Stimulation mit IL-6 führte zu einem Anstieg der VEGF-Sekretion.

Schlussfolgerung

Die VEGF- und IL-6-Sekretion menschlicher Granulosazellen wird durch Gonadotropine reguliert. IL-6 stimuliert die VEGF-Sekretion von Granulosazellen. Diese Mechanismen könnten zur Entwicklung des ovariellen Überstimulationssyndroms (OHSS) beitragen.

Abstract

Introduction

This study was performed to elucidate the effects of gonadotropins on the production of vascular endothelial growth factor-A (VEGF-A) and interleukin-6 (IL-6) and the effects of IL-6 on VEGF-A expression in human granulosa-lutein cells in vitro.

Methods

Granulosa cells (GC) were isolated from follicular aspirates of patients undergoing ovarian stimulation for in vitro-fertilization (IVF). Cells were cultured with or without recombinant human follicle stimulating hormone (rhFSH) and human chorionic gonadotropin (hCG) at various concentrations and cellular expression of VEGF-A and IL-6 was analysed on the mRNA-level by Northern analysis. VEGF-A- and IL-6 protein in cell supernatants was measured by enzyme-linked immunosorbent assay (ELISA). Furthermore GC were stimulated with increasing doses of recombinant human IL-6 (rhIL-6) and VEGF-A production of GC was measured.

Results

Stimulation of GC with either hCG or rhFSH led to a dose-dependent increase of VEGF-A- and IL-6 protein. Stimulation of GC with increasing doses of rhIL-6 led to a dose-dependent increase of VEGF-A protein.

Conclusion

These findings suggest a gonadotropin dependent expression of VEGF and IL-6 in human GC. Furthermore IL-6 stimulates VEGF-A-production of GC. These interactions may be of pathophysiological significance for the development of OHSS.

References

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