Mechanical stretching induces interleukin-8 gene expression in fetal membranes: a possible role for the initiation of human parturition

Abstract

Objective: Interleukin-8 (IL-8) is known to play a crucial role in human parturition. We aimed to study the effect of mechanical stretching on the expression of IL-8 in fetal membranes (amniochorion) and decidua.

Study design: We examined the expression of IL-8 and its receptor in fetal membranes (amniochorion) and decidua by immunohistochemical staining. Also, we studied the synthesis of IL-8 messenger RNA (mRNA) in the fetal membranes before and after stretching.

Results: We found that mechanical stretching within physiological limit increased IL-8 messenger RNA (mRNA) synthesis in fetal membranes and decidua in a time- and load-dependent manner. Application of mechanical force led to markedly increased staining of IL-8 receptor in decidual cells but not in amnion or chorion cells.

Conclusion: These results suggested that mechanical stretching was a candidate for one of the signals important for production of IL-8 in fetal membranes and decidua and probably for initiation of a cytokine network at amniochorio-decidual interface through increased expression of IL-8 receptors.