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This study’s aim was to detect NR5A2 expression and explore association between single nucleotide polymorphism (SNP) of the NR5A2 gene with reproductive traits in Jiaxing Black (JXB) sows. The expression analysis showed that the expression level of pig NR5A2 mRNA in the ovary and liver was significantly higher (p < 0.01) compared to other tissues. 10 SNPs were detected in the exons of NR5A2, and five SNPs (g.136706A > T, g.84609G > A, g.136759G > C, g.138802T > C, g.138864A > G) met Hardy Weinberg equilibrium conditions. The total number of piglets born (TBA) and number of still born piglets (NSB) of sows with GG genotype at the g.136759G > C loci were higher than the CC genotype (P < 0.05). For the g.138864A > G loci, individuals with the AA genotype had significantly higher TBA than those of sows with the AG genotype (P < 0.05). By combining genotypes, it was found that the H7H8 diplotype had the best TBA performance. Moreover, the g.138864A > G and g.136759G > C loci had significant effects on the NR5A2 mRNA expression level in the ovary. The above results indicated that SNPs within NR5A2 exons of the NR5A2 gene have a certain effect on the reproductive traits of JXB pigs.

The significance and regulation of liver receptor homologue 1 (LRH-1, NR5A2), a tumour-promoting transcription factor in breast cancer cell lines, is unknown in clinical breast cancers. This study aims to determine LRH-1/NR5A2 expression in breast cancers and relationship with DNA methylation and tumour characteristics. In The Cancer Genome Atlas breast cancer cohort NR5A2 expression was positively associated with intragenic CpG island methylation (1.4-fold expression for fully methylated versus not fully methylated, p=0.01) and inversely associated with promoter CpG island methylation (0.6-fold expression for fully methylated versus not fully methylated, p=0.036). LRH-1 immunohistochemistry of 329 invasive carcinomas and ductal carcinoma in situ (DCIS) was performed. Densely punctate/coarsely granular nuclear reactivity was significantly associated with high tumour grade (p

Type 1 diabetes mellitus (T1DM) is due to the selective destruction of islet beta cells by immune cells. Current therapies focused on repressing the immune attack or stimulating beta cell regeneration still have limited clinical efficacy. Therefore, it is timely to identify innovative targets to dampen the immune process, while promoting beta cell survival and function. Liver receptor homologue-1 (LRH-1) is a nuclear receptor that represses inflammation in digestive organs, and protects pancreatic islets against apoptosis. Here, we show that BL001, a small LRH-1 agonist, impedes hyperglycemia progression and the immune-dependent inflammation of pancreas in murine models of T1DM, and beta cell apoptosis in islets of type 2 diabetic patients, while increasing beta cell mass and insulin secretion. Thus, we suggest that LRH-1 agonism favors a dialogue between immune and islet cells, which could be druggable to protect against diabetes mellitus., Type 1 diabetes mellitus (T1DM) is characterized by beta cell loss because of an autoimmune attack. Here the authors show that an agonist for LRH-1/NR5A2, a nuclear receptor known to be protective against beta cell apoptosis, inhibits immune-mediated inflammation and hyperglycemia in T1DM mouse models.

The nuclear receptor LRH-1 (Liver Receptor Homolog-1, NR5A2) is a transcription factor that regulates gene expression programs critical for many aspects of metabolism and reproduction. Although LRH-1 is able to bind phospholipids, it is still considered an orphan nuclear receptor (NR) with an unknown regulatory hormone. Our prior cellular and structural studies demonstrated that the signaling phosphatidylinositols PI(4,5)P2 (PIP2) and PI(3,4,5)P3 (PIP3) bind and regulate SF-1 (Steroidogenic Factor-1, NR5A1), a close homolog of LRH-1. Here, we describe the crystal structure of human LRH-1 ligand binding domain (LBD) bound by PIP3 - the first phospholipid with a head group endogenous to mammals. We show that the phospholipid hormone binds LRH-1 with high affinity, stabilizing the receptor LBD. While the hydrophobic PIP3 tails (C16/C16) are buried inside the LRH-1 ligand binding pocket, the negatively charged PIP3 head group is presented on the receptor surface, similar to the phosphatidylinositol binding mode observed in the PIP3-SF-1 structure. Thus, data presented in this work reinforce our earlier findings demonstrating that signaling phosphatidylinositols regulate the NR5A receptors LRH-1 and SF-1.

The conserved Notch pathway is reported to be involved in progesterone synthesis and secretion, however, the exact effects remain controversial. To determine the role and potential mechanisms of the Notch signaling pathway in progesterone biosynthesis in porcine granulosa cells (pGCs), we first used a pharmacological &gamma, secretase inhibitor, N-(N-(3,5-difluorophenacetyl-l-alanyl))-S-phenylglycine t-butyl ester (DAPT), to block the Notch pathway in cultured pGCs and then evaluated the expression of genes in the progesterone biosynthesis pathway and key transcription factors (TFs) regulating steroidogenesis. We found that DAPT dose- and time-dependently increased progesterone secretion. The expression of steroidogenic proteins NPC1 and StAR and two TFs, NR5A2 and NR2F2, was significantly upregulated, while the expression of HSD3B was significantly downregulated. Furthermore, knockdown of both NR5A2 and NR2F2 with specific siRNAs blocked the upregulatory effects of DAPT on progesterone secretion and reversed the effects of DAPT on the expression of NPC1, StAR, and HSD3B. Moreover, knockdown of NR5A2 and NR2F2 stimulated the expression of Notch3. In conclusion, the inhibition of Notch signaling stimulated progesterone secretion by enhancing the expression of NPC1 and StAR, and the two TFs NR5A2 and NR2F2 acted as downstream TFs of Notch signaling in regulating progesterone synthesis.

Liver receptor homolog-1 (NR5A2) is a nuclear receptor originally identified in the liver and mostly known for its regulatory role in cholesterol and bile acid homeostasis. More recently, liver receptor homolog-1 has emerged as a key regulator of intestinal function, coordinating unanticipated actions, such as cell renewal and local immune function with important implications to common intestinal diseases, including colorectal cancer and inflammatory bowel disease. Unlike most of the other nuclear receptors, liver receptor homolog-1 acts as a constitutively active transcription factor to drive the transcription of its target genes. Liver receptor homolog-1 activity however is to a major extent regulated by different corepressors and posttranslational modifications, which may account for its tissue-specific functions. This review will provide an update on the molecular aspects of liver receptor homolog-1 action and focus on some emerging aspects of its function in normal and diseased gut. This article is part of a Special Issue entitled: Translating nuclear receptors from health to disease.

Nuclear hormone receptors regulate diverse metabolic pathways and the orphan nuclear receptor LRH-1 (also known as NR5A2) regulates bile acid biosynthesis. Structural studies have identified phospholipids as potential LRH-1 ligands, but their functional relevance is unclear. Here we show that an unusual phosphatidylcholine species with two saturated 12 carbon fatty acid acyl sidechains (dilauroyl phosphatidylcholine (DLPC)) is an LRH-1 agonist ligand in vitro. DLPC treatment induces bile acid biosynthetic enzymes in mouse liver, increases bile acid levels, and lowers hepatictriglycerides and serum glucose. DLPC treatment also decreases hepatic steatosis and improves glucose homeostasis in two mouse models of insulin resistance. Both the antidiabetic and lipotropic effects are lost in liver-specific Lrh-1 knockouts. These findings identify an LRH-1 dependent phosphatidylcholine signalling pathway that regulates bile acid metabolism and glucose homeostasis.

NR5A2 is a nuclear receptor which regulates the expression of genes involved in cholesterol metabolism, pluripotency maintenance and cell differentiation. It has been recently shown that DLPC, a NR5A2 ligand, prevents liver steatosis and improves insulin sensitivity in mouse models of insulin resistance, an effect that has been associated with changes in glucose and fatty acids metabolism in liver. Because skeletal muscle is a major tissue in clearing glucose from blood, we studied the effect of the activation of NR5A2 on muscle metabolism by using cultures of C2C12, a mouse-derived cell line widely used as a model of skeletal muscle. Treatment of C2C12 with DLPC resulted in increased levels of expression of GLUT4 and also of several genes related to glycolysis and glycogen metabolism. These changes were accompanied by an increased glucose uptake. In addition, the activation of NR5A2 produced a reduction in the oxidation of fatty acids, an effect which disappeared in low-glucose conditions. Our results suggest that NR5A2, mostly by enhancing glucose uptake, switches muscle cells into a state of glucose preference. The increased use of glucose by muscle might constitute another mechanism by which NR5A2 improves blood glucose levels and restores insulin sensitivity., This work has been supported by the grant PI12/00637 from Instituto de Salud Carlos III (Spain) to J.C.R.R.

Liver receptor homolog 1 (nuclear receptor LRH-1, NR5A2) is an essential regulator of gene transcription, critical for maintenance of cell pluripotency in early development and imperative for the proper functions of the liver, pancreas, and intestines during the adult life. Although physiological hormones of LRH-1 have not yet been identified, crystallographic and biochemical studies demonstrated that LRH-1 could bind regulatory ligands and suggested phosphatidylinositols as potential hormone candidates for this receptor. No synthetic antagonists of LRH-1 are known to date. Here, we identify the first small molecule antagonists of LRH-1 activity. Our search for LRH-1 modulators was empowered by screening of 5.2 million commercially available compounds via molecular docking followed by verification of the top-ranked molecules using in vitro direct binding and transcriptional assays. Experimental evaluation of the predicted ligands identified two compounds that inhibit the transcriptional activity of LRH-1 and diminish the expression of the receptor's target genes. Among the affected transcriptional targets are co-repressor SHP (small heterodimer partner) as well as cyclin E1 (CCNE1) and G0S2 genes that are known to regulate cell growth and proliferation. Treatments of human pancreatic (AsPC-1), colon (HT29), and breast adenocarcinoma cells T47D and MDA-MB-468 with the LRH-1 antagonists resulted in the receptor-mediated inhibition of cancer cell proliferation. Our data suggest that specific antagonists of LRH-1 could be used as specific molecular probes for elucidating the roles of the receptor in different types of malignancies. Background: Liver receptor homolog 1 (LRH-1, NR5A2) regulates functions of liver, intestines, and pancreas; its aberrant activity is associated with tumorigenesis. Results: Our work identifies the first antagonists of LRH-1. Conclusion: The identified ligands inhibit LRH-1 transcriptional activity, diminishing expression of the receptor's target genes. Significance: LRH-1 inhibitors could be used for analyses of the receptor's biological mechanisms and for development of cancer therapeutics.

Liver receptor homolog-1 (NR5A2) is a nuclear receptor originally identified in the liver and mostly known for its regulatory role in cholesterol and bile acid homeostasis. More recently, liver receptor homolog-1 has emerged as a key regulator of intestinal function, coordinating unanticipated actions, such as cell renewal and local immune function with important implications to common intestinal diseases, including colorectal cancer and inflammatory bowel disease. Unlike most of the other nuclear receptors, liver receptor homolog-1 acts as a constitutively active transcription factor to drive the transcription of its target genes. Liver receptor homolog-1 activity however is to a major extent regulated by different corepressors and posttranslational modifications, which may account for its tissue-specific functions. This review will provide an update on the molecular aspects of liver receptor homolog-1 action and focus on some emerging aspects of its function in normal and diseased gut.

Genome-wide association studies (GWAS) have identified common pancreatic cancer susceptibility variants at 13 chromosomal loci in individuals of European descent. To identify new susceptibility variants, we performed imputation based on 1000 Genomes (1000G) Project data and association analysis using 5,107 case and 8,845 control subjects from 27 cohort and case-control studies that participated in the PanScan I-III GWAS. This analysis, in combination with a two-staged replication in an additional 6,076 case and 7,555 control subjects from the PANcreatic Disease ReseArch (PANDoRA) and Pancreatic Cancer Case-Control (PanC4) Consortia uncovered 3 new pancreatic cancer risk signals marked by single nucleotide polymorphisms (SNPs) rs2816938 at chromosome 1q32.1 (per allele odds ratio (OR) = 1.20, P = 4.88x10 -15), rs10094872 at 8q24.21 (OR = 1.15, P = 3.22x10 -9) and rs35226131 at 5p15.33 (OR = 0.71, P = 1.70x10 -8). These SNPs represent independent risk variants at previously identified pancreatic cancer risk loci on chr1q32.1 ( NR5A2), chr8q24.21 ( MYC) and chr5p15.33 ( CLPTM1L- TERT) as per analyses conditioned on previously reported susceptibility variants. We assessed expression of candidate genes at the three risk loci in histologically normal ( n = 10) and tumor ( n = 8) derived pancreatic tissue samples and observed a marked reduction of NR5A2 expression (chr1q32.1) in the tumors (fold change -7.6, P = 5.7x10 -8). This finding was validated in a second set of paired ( n = 20) histologically normal and tumor derived pancreatic tissue samples (average fold change for three NR5A2 isoforms -31.3 to -95.7, P = 7.5x10 -4-2.0x10 -3). Our study has identified new susceptibility variants independently conferring pancreatic cancer risk that merit functional follow-up to identify target genes and explain the underlying biology.

The orphan nuclear receptor, liver receptor homolog-1 (aka Nuclear receptor subfamily 5, Group A, Member 2 (Nr5a2)), is widely expressed in mammalian tissues, and its ovarian expression is restricted to granulosa cells of activated follicles. We employed the floxed Nr5a2 (Nr5a2(f/f)) mutant mouse line and two granulosa-specific Cre lines, Anti-Mullerian hormone receptor- 2 (Amhr2Cre) and transgenic cytochrome P450 family 19 subfamily A polypeptide 1 (tgCyp19Cre), to develop two tissue- and time-specific Nr5a2 depletionmodels: Nr5a2(Amhr2-/-) and Nr5a2(Cyp19-/-). In the Nr5a2(Cyp19-/-) ovaries, Nr5a2 was depleted in mural granulosa, but not cumulus cells. We induced follicular development in mutant and wild-type (control, CON) mice with equine chorionic gonadotropin followed 44 h later treatment with human chorionic gonadotropin (hCG) to induce ovulation. Both Nr5a2(Amhr2-/-) and Nr5a2(Cyp19-/-) cumulus-oocyte complexes underwent a reduced degree of expansion in vitro relative to wild-type mice. We found downregulation of epiregulin (Ereg), amphiregulin (Areg), betacellulin (Btc) and tumor necrosis factor stimulated gene-6 (Tnfaip6) transcripts in Nr5a2(Amhr2-/-) and Nr5a2(Cyp19-/-) ovaries. Tnfaip6 protein abundance, by quantitative immunofluorescence, was likewise substantially reduced in the Nr5a2-depleted model. Transcript abundance for connexin 43 (Gja1) in granulosa cells was lower at 0 h and maximum at 8 h post-hCG in both Nr5a2(Amhr2-/-) and Nr5a2(Cyp19-/-) follicles, while Gja1 protein was not different prior to the ovulatory signal, but elevated at 8 h in Nr5a2(Amhr2-/-) and Nr5a2(Cyp19-/-) follicles. In both mutant genotypes, oocytes can mature in vivo and resulting embryos were capable of proceeding to blastocyst stagein vitro. We conclude that Nr5a2 is essential for cumulus expansion in granulosa cells throughout follicular development. The disruption of Nr5a2 in follicular somatic cells does not affect the capacity of the oocyte to be fertilized by intracytoplasmic sperm injection. Summary Sentence Liver receptor homolog-1 is necessary for cumulus expansion, but not fertilization of mouse oocytes.