bioRxiv Science⌕ Search

bioRxiv · 10.1101/2022.09.22.509003

Fibroblast activation during decidualization: Embryo-derived TNFα induction of PGI2-PPARδ-ACTIVIN A pathway through luminal epithelium

Abstract

ObjectivesHuman endometrium undergoes cyclical shedding and bleeding, scar-free repair and regeneration in subsequent cycles. Fibroblast activation has been shown to play a key role during normal tissue repair and scar formation. Abnormal fibroblast activation leads to fibrosis. Fibrosis is the main cause of intrauterine adhesion, uterine scaring, and thin endometrium. Endometrial decidualization is a critical step during early pregnancy. There are 75% of pregnancy failures pointed to decidualization defects. Because fibroblast activation and decidualization share similar markers, we assumed that fibroblast activation should be involved in decidualization. Materials and MethodsBoth pregnant and pseudopregnant ICR mice were used in this study. Immunofluorescence and immunohistochemistry were applied to examine fibroblast activation-related markers in mouse uteri. Western blotting was used to identify the impact on decidualization. Western blot and RT were used to show how arachidonic acid and its downstream product prostaglandin activate fibroblasts. Additionally, embryo-derived TNF was shown to stimulate the secretion of arachidonic acid by immunofluorescence, western blot, and ELASA. The aborted decidual tissues with fetal trisomy 16 were compared with control tissues. GraphPad Prism5.0 Students t test was used to compare differences between control and treatment groups ResultsFibroblast activation-related markers are obviously detected in pregnant decidua and under in vitro decidualization. ACTIVIN A secreted under fibroblast activation promotes in vitro decidualization. We showed that arachidonic acid released from uterine luminal epithelium can induce fibroblast activation and decidualization through PGI2 and its nuclear receptor PPAR-{delta}. Based on the significant difference of fibroblast activation-related markers between pregnant and pseudopregnant mice, we found that embryo-derived TNF promotes cPLA2 phosphorylation and arachidonic acid release from luminal epithelium. Fibroblast activation is also detected under human in vitro decidualization. Similar arachidonic acid-PGI2-PPAR{delta}-ACTIVIN A pathway is conserved in human endometrium. Compared to controls, fibroblast activation is obviously compromised in human decidual tissues with fetal trisomy 16. ConclusionsEmbryo-derived TNF promotes cPLA2 phosphorylation and arachidonic acid release from luminal epithelium to induce fibroblast activation and decidualization. Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=144 HEIGHT=200 SRC="FIGDIR/small/509003v1_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@97b4edorg.highwire.dtl.DTLVardef@1e758d6org.highwire.dtl.DTLVardef@1797acaorg.highwire.dtl.DTLVardef@6c8b82_HPS_FORMAT_FIGEXP M_FIG C_FIG

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Chen, S.-T., Shi, W.-W., Lin, Y.-Q., Yang, Z.-S., Wang, Y., Li, M.-Y., Li, Y., Liu, A.-X., Hu, Y., Yang, Z.-M.. 2022-09-22. Fibroblast activation during decidualization: Embryo-derived TNFα induction of PGI2-PPARδ-ACTIVIN A pathway through luminal epithelium. https://doi.org/10.1101/2022.09.22.509003

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Dynamic mechanical sorting biases niche occupancy and lineage outcome during development of bilayered glandular epithelia

Tissue compartmentalization into basal and luminal domains is a hallmark of glandular epithelia, yet how fate boundaries are established and stabilized during dynamic morphogenesis remains a major unresolved question. Here, using mouse embryonic explants, organoids, quantitative live imaging and genetic perturbations, we show that basal-luminal compartmentalization is not maintained by fixed boundaries, but through continuous positional corrections. We show that differences in cellular adhesion and actomyosin contractility drive these positional corrections by promoting active cell sorting. We further find that these mechanical differences influence lineage specification by controlling cell positioning rather than directly instructing cell fate. Before commitment, mosaic, but not uniform, perturbation of cell mechanics alters niche occupancy and biases lineage outcome, indicating that relative mechanical properties determine access to fate-instructive niches. Conversely, perturbation of Notch and YAP remodels compartment-specific mechanical properties and cell-positioning dynamics, revealing a reciprocal coupling between lineage state and mechanical sorting. Conservation of this mechanism across four glandular epithelia of distinct origins and functions identifies dynamic mechanical sorting as a general strategy for maintaining robust tissue compartmentalization during the extensive growth and cellular rearrangements of branching morphogenesis.

developmental biology↗

Unbiased lineage tracing across the adipose organ decouples developmental origin from anatomical and transcriptomic identities

The developmental origins of individual adipose depots and whether embryonic lineage dictates adult function remain unresolved. Here, we apply in utero CRISPR-mediated barcoding lineage tracing to construct the first unbiased clonal map of adipose organ development in mice. The developmental hierarchy we uncover challenges several conventions. Remarkably, interscapular brown fat, used as the prototypical brown fat, is the most developmentally isolated brown fat; depots sharing Myf5/Pax3 lineage markers fail to cluster together; mesenteric white fat shares unexpected high clonal ancestry with brown fats despite a radically divergent transcriptome; and subcutaneous white adipose tissues converge transcriptomically despite distant developmental origins. These findings call for a reinterpretation of single-marker lineage tracing data across the adipose organ and propose that adipose depot identity is not solely encoded by embryonic lineage but is substantially shaped by the anatomical niche.

developmental biology↗

Age-dependent mechanical stress underlies unexpected vestibular differentiation and regeneration patterns

Loss of inner-ear sensory hair cells (HCs) is a major cause of hearing and balance disorders. Promoting HC regeneration offers a potential therapeutic strategy, but regenerative capacity is limited in adult mammals and declines rapidly during early postnatal development in mice. HCs can regenerate through trans-differentiation of neighboring supporting cells in a process controlled by Notch mediated lateral inhibition. However, the factors underlying the decrease in regeneration capacity are poorly understood. Here, we combine live imaging with single-HC ablation in mouse vestibular explants to track the dynamics of HC development and regeneration. We reveal unexpected age-dependent deviations from the classical lateral inhibition model, in which new HCs differentiate adjacent to existing HCs. We find that mechanical stress changes with age and that perturbing it alters the observed differentiation patterns. A mathematical model incorporating local mechanical regulation of Notch signaling captures both HC differentiation and regeneration patterns across ages. Together, these findings identify mechanical stress as a crucial regulator of HC differentiation and support an underlying mechanism in which the interplay between local mechanics and Notch signaling shapes regenerative responses. This coupling offers a framework for understanding the age-dependent decline in HC regeneration and motivates investigation of mechanical regulation as a potential therapeutic target.

developmental biology↗