Evidence of in vitro differential secretion of 72 and 92 kDa type IV collagenases after selective exposure to lipopolysaccharide in human fetal membranes

Abstract

Premature rupture of chorioamniotic membranes complicated with intrauterine infection has been associated to degradation of extracellular matrix (ECM), which could explain local morphological changes. We used a culture system in which the chorioamniotic membranes form two independent chambers, allowing for the selective stimulation of either the amnion (AMN) and/or the choriodecidua (CHD) regions. Lipopolysaccharide (500 ng/ml) was added to the AMN and/or the CHD; secretions and gelatinolytic activity of matrix metalloproteinase (MMP)-2 and MMP-9 were measured in both compartments by enzyme-linked immunosorbent assay (ELISA) and zymography. Secretions of TIMP-1, TIMP-2 and TIMP-4 were measured by ELISA. Both metalloproteinases were immunolocalized in tissue sections. All stimulation modalities induced a similar proMMP-2 and proMMP-9 secretion pattern in the CHD with concentrations of 2.49 ng/ml and 90.91 pg/ml, respectively; the AMN showed no significant changes. The active forms of both enzymes did not change with any stimulation modality. TIMP-1, TIMP-2 and TIMP-4 secretions remained without significant changes (P = 0.41). ECM degradation and structural disarrangement were evident after stimulation. Secretion of proMMP-2 and proMMP-9 mainly in the CHD, presence of active forms associated to the tissue and minor changes in TIMPs secretion could favor ECM degradation and explain the weakening and thinning associated with the pathological rupture of chorioamniotic membranes.

A genetic association study of maternal and fetal candidate genes that predispose to preterm prelabor rupture of membranes (PROM)

“…These observations are consistent with in vitro studies in which microbial products added to fetal membrane explants generated an imbalance between MMPs and TIMPs, tilting the balance towards matrix degradation 135-141. TIMP2 plays an important role in regulating the activities of matrix degrading enzymes.…”

In vitro secretion and activity profiles of matrix metalloproteinases, MMP-9 and MMP-2, in human term extra-placental membranes after exposure to Escherichia coli

“…This experimental model has been validated and published previously [15-17], and allows us to test two independent compartments delimited by the AMN and CHD of the fetal membrane.…”

“…In this pathological scenario, the rupture of the chorioamnion results from a degrading process that is potentiated by an exacerbated immunological response [14-17]. Previous evidence generated at our laboratory indicates that stimulation of human fetal membranes with S. agalactiae, a microorganism with high prevalence in cases of vaginal/intrauterine infections, is followed by active secretion of MMP-2 and MMP-9 [16].…”

Regulation of Matrix Metalloproteinases-2 and -9 Gene Expression in Cultured Human Fetal Membrane Cells by Influenza Virus Infection

“…41) The cleavage of pro-MMP-2 into an active intermediate form in isolated amniochorion tissues was observed after the stimulation with LPS 40) and the exposure to Escherichia coli. 41) Contrary, it has been published that cytomegalovirus infection reduced the gene expression of MMP-2 and MMP-9 in organ cultured human villous tissues.…”