Search bioRxiv⌕ Search

Biology subjects

Doridot, L.

Publications and source records attributed to Doridot, L..

4 recordsLinked to original sources

Preconceptional immunomodulation partially corrects pregnancy associated abnormalities induced by endometriosis in a mice model, with a normalization of transcriptional alteration observed in the developing fetal maternal interface at the single cell level.

Endometriosis is a chronic disease of gynaecological origin that affects approximately 10% of women worldwide and has a significant impact on patients lives. Women with endometriosis attempting to conceive may experience infertility and have a higher risk of obstetric complications. They are also more likely to miscarry and have placental defects during pregnancy. The impact of endometriosis on pregnancy remains unclear. Defects in implantation and placentation may be present, but these processes are difficult to study in human subjects. To address this issue, we used a surgically induced mouse model of endometriosis and examined pregnancy in the CBAxDBA crossbreed, which is commonly employed to study pregnancy immunology. We examined early (E9.5) and late (E18.5) gestational stages. In this model, we confirmed that the presence of endometriosis-like lesions resulted in fewer implantations and a higher proportion of fetal resorption, which is analogous to miscarriage. When an immune tolerance was induced previous to the endometriosis induction, we observed that endometriotic lesions were smaller, and gestational complications were mostly corrected. At early gestation (E9.5), fetal-maternal interfaces were retrieved to assess the potential impact of endometriosis and immunomodulation on placental development using single-cell RNA-sequencing. Our data show that most changes induced by endometriosis occur in decidual stromal cells, which originate from the endometrium. In these cells, we observed a consistent upregulation of Gata4, a transcription factor previously found to be elevated in the endometrium of women with endometriosis. We also observed downregulation of Prap1, which is an indicator of uterine receptivity and successful implantation in mice. In the mice where immune tolerance was induced, the endometriosis associated transcriptomic changes were partially reversed. In immune cells, endometriosis leads to an inflammation-associated signature. Additionally, the interferon gamma response is reduced in NK cells, which has been shown to be crucial for spiral artery remodelling and decidual integrity, which may be involved in the observed increased resorption rate. Overall, our findings provide new insights into endometriosis-associated infertility and pregnancy complications in a mouse model that can be partially corrected by immune modulation. These results suggest that targeting the immune system should be considered in future studies to improve pregnancy outcomes in patients with endometriosis.

molecular biology↗

Convergent gene expression in epithelial cells illuminates the evolution of uterine receptivity

The epithelium of the uterine endometrium is the first maternal interface encountered by the embryo, and plays crucial roles in the maternal-embryonic crosstalk necessary to embryo implantation. Mechanisms of embryo implantation are highly variable between mammals: humans and mice have convergently evolved similar embryo implantation phenotypes, where the embryo embeds in the maternal mucosa, which differs from the ancestral mammalian and primate phenotypes. This phenomenon is thought to be partly controlled by maternal epithelial receptivity signals during the window of implantation. Here, we combined endometrial epithelial organoid models and single-cell transcriptomics to investigate how gene expression has evolved in endometrial epithelial cells between human, non-human primates and mouse at key time points in the hormonal cycle. We discovered that many maternal genes involved in uterine receptivity and embryo implantation exhibit more similar expression patterns between human and mouse compared to macaque and marmoset. In particular, we show that the endometrial expression of LIF, a crucial actor of endometrial receptivity in both human and mouse, is likely an evolutionary convergence rather than a conserved feature as previously hypothesised.

evolutionary biology↗

Mechanistic target of rapamycin (mTOR) regulates self-sustained quiescence, tumor indolence and late clinical metastasis in a Beclin-1-dependent manner.

Self-sustained quiescence (SSQ) has been characterized as a stable but reversible non-proliferative cellular state that limits the cloning of cultured cancer cells. By developing refined clonogenic assays, we showed here that cancer cells in SSQ can be selected with anticancer agents and that culture at low cell density induced SSQ in pancreas and prostate adenocarcinoma cells. Pre-culture of cells in 3D or their pretreatment with pharmacological inhibitors of mechanistic target of rapamycin (mTOR) synergize with low cell density for induction of SSQ in a Beclin-1-dependent manner. Dissociated pancreatic adenocarcinoma (PAAD) cells rendered defective for SSQ by down-regulating Beclin-1 expression exhibit higher tumor growth rate when injected subcutaneously into mice. Conversely, dissociated PAAD cells in SSQ promote the formation of small indolent tumors that eventually transitioned to a rapid growth phase. Ex vivo clonogenic assays showed that up to 40% of clonogenic cancer cells enzymatically dissociated from resected fast-growing tumors could enter SSQ, suggesting that SSQ could significantly impact the proliferation of cancer cells that are naturally dispersed from tumors. Remarkably, the kinetics of clinical metastatic recurrence in 124 patients with pancreatic adenocarcinoma included in the TGCA-PAAD project could be predicted from Beclin-1 and Cyclin-A2 mRNA levels in their primary tumor, Cyclin A2 mRNA being a marker of both cell proliferation and mTOR complex 1 activity. Overall, our data show that SSQ is likely to promote the late development of clinical metastases and suggest that identifying new agents targeting cancer cells in SSQ could help improve patient survival.

cancer biology↗

HGFAC is a ChREBP Regulated Hepatokine that Enhances Glucose and Lipid Homeostasis

Carbohydrate Responsive Element-Binding Protein (ChREBP) is a carbohydrate sensing transcription factor that regulates both adaptive and maladaptive genomic responses in coordination of systemic fuel homeostasis. Genetic variants in the ChREBP locus associate with diverse metabolic traits in humans, including circulating lipids. To identify novel ChREBP-regulated hepatokines that contribute to its systemic metabolic effects, we integrated ChREBP ChIP-seq analysis in mouse liver with human genetic and genomic data for lipid traits and identified Hepatocyte Growth Factor Activator (HGFAC) as a promising ChREBP-regulated candidate in mice and humans. HGFAC is a protease that activates the pleiotropic hormone Hepatocyte Growth Factor (HGF). We demonstrate that HGFAC KO mice have phenotypes concordant with putative loss-of-function variants in human HGFAC. Moreover, in gain- and loss-of-function genetic mouse models, we demonstrate that HGFAC enhances lipid and glucose homeostasis, in part, through actions to activate hepatic PPAR{gamma} activity. Together, our studies show that ChREBP mediates an adaptive response to overnutrition via activation of an HGFAC-HGF-PPAR{gamma} signaling axis in the liver to preserve glucose and lipid homeostasis.

physiology↗