Collagen types I, III, and V constitute the thick collagen fibrils of the mouse decidua

Abstract

A mammal's endometrium is deeply remodeled while receiving and implanting an embryo. In addition to cell proliferation and growth, endometrial remodeling also comprises synthesis and degradation of several molecular components of the extracellular matrix. All of these events are orchestrated by a precise sequence of ovarian hormones and influenced by several types of cytokines. As we have previously reported, an intriguing and rapid increase in collagen fibril diameter occurs in the decidualized areas of the endometrium, surrounding the implantation crypt, whereas collagen fibrils situated far from the embryo remain unchanged. Collagen fibrilogenesis is a complex molecular process coordinated by a number of factors, such as the types and amounts of glycosaminoglycans and proteoglycans associated with collagen molecules. Collagen genetic type, mechanical stress, aging, and other factors not yet identified also contribute to this development. A recent study suggests that thick fibrils from mouse decidua are formed, at least in part, by aggregation of thin fibrils existing in the stroma before the onset of decidualization. In the present ultrastructural study using single and double immunogold localization, we showed that both thin and thick collagen fibrils present in the mouse pregnant endometrium endometrium are heterotypic structures formed at least by type I, type III, and type V collagens. However, type V collagen predominates in the thick collagen fibrils, whereas it is almost absent of the thin collagen fibrils. The putative role of type V homotrimer in the rapid increase of the diameter of collagen fibrils of the mouse decidua is discussed.

Altered Spatiotemporal Expression of Collagen Types I, III, IV, and VI in Lpar3-Deficient Peri-Implantation Mouse Uterus

“…These results agree with those of another study in rat uterus that shows 30% and 55% clearance of COL I and COL III, respectively, in the implantation site from Day 5.5 to Day 6.5; and 16% and 31% clearance of COL I and COL III, respectively, in the implantation site from Day 6.5 to Day 7.5 [6]. Previous studies in the mouse indicate weaker COL III staining on Day 5 than on later days [7], with reorganization into sparsely distributed, thick intercellular fibrils by Day 7 [39]. The expression pattern of COL IV differs from that of the other three collagen types.…”

The Estrous Cycle Modulates Small Leucine‐Rich Proteoglycans Expression in Mouse Uterine Tissues

“…We have previously documented that, in mice, remodeling of the extracellular matrix begins early in pregnancy, characterized by synthesis, degradation, and alteration of collagen fibrillogenesis, accompanied by pregnancy‐stage dependent expression of collagen, glycosaminoglycans and proteoglycans. Interestingly, decorin is abolished from the superficial stroma after decidualization and lumican is maintained, although in very low levels (Zorn et al, 1995; San Martin et al, 2003a, b; Spiess and Zorn, 2007). In fact, studies from Vogel and Trotter (1987) showed that decorin and lumican link to fibrilar collagens in vitro , stabilizing thin fibrils.…”

Differences in collagen ultrastructure of human first trimester decidua basalis and parietalis: Implications for trophoblastic invasion of the placental bed

“…Spiess and Zorn used immunogold localization to show that both thin and thick collagen fibrils present in the pregnant mouse endometrium were formed by type I, III and V collagens. 10 Type V collagen was predominant in the thick collagen fibrils and almost absent in the thin fibrils. 10 Aplin et al also reported that type III and type V collagens and fibronectin were present in endometrial stroma throughout the menstrual cycle as well as in the human first trimester decidua.…”

“…10 Type V collagen was predominant in the thick collagen fibrils and almost absent in the thin fibrils. 10 Aplin et al also reported that type III and type V collagens and fibronectin were present in endometrial stroma throughout the menstrual cycle as well as in the human first trimester decidua. 11 Other studies have shown that type V collagen is masked by type I collagen in heteropolymeric fibrils and that type V collagen may regulate the diameter of the major type I collagen fibrils.…”

“…We also observed that type V fibrils were mainly concentrated around structures such as blood vessels. Spiess and Zorn used immunogold localization to show that both thin and thick collagen fibrils present in the pregnant mouse endometrium were formed by type I, III and V collagens . Type V collagen was predominant in the thick collagen fibrils and almost absent in the thin fibrils .…”