Overexpression of Jazf1 reduces body weight gain and regulates lipid metabolism in high fat diet. Biochem Biophys Res Commun. 2014;444:296-301. [PMID: 24380856 DOI: 10.1016/j.bbrc.2013.12.094]

Genomic Insights into Gestational Weight Gain: Uncovering Tissue-Specific Mechanisms and Pathways

Increasing gestational weight gain (GWG) is linked to adverse outcomes in pregnant persons and their children. The Early Growth Genetics (EGG) Consortium identified previously genetic variants that could contribute to early, late, and total GWG from fetal and maternal genomes. However, the biologic mechanisms and tissue-Specificity of these variants in GWG is unknown. We evaluated the association between genetically predicted gene expression in five relevant maternal (subcutaneous and visceral adipose, breast, uterus, and whole blood) from GTEx (v7) and fetal (placenta) tissues and early, late, and total GWG using S-PrediXcan. We tested enrichment of pre-defined biological pathways for nominally (P < 0.05) significant associations using the GENE2FUNC module from Functional Mapping and Annotation of Genome-Wide Association Studies. After multiple testing correction, we did not find significant associations between maternal and fetal gene expression and early, late, or total GWG. There was significant enrichment of several biological pathways, including metabolic processes, secretion, and intracellular transport, among nominally significant genes from the maternal analyses (false discovery rate p-values: 0.016 to 9.37×10). Enriched biological pathways varied across pregnancy. Though additional research is necessary, these results indicate that diverse biological pathways are likely to impact GWG, with their influence varying by tissue and weeks of gestation.

New insights into the suppression of inflammation and lipid accumulation by JAZF1

Atherosclerosis is one of the leading causes of disease and death worldwide. The identification of new therapeutic targets and agents is critical. JAZF1 is expressed in many tissues and is found at particularly high levels in adipose tissue (AT). JAZF1 suppresses inflammation (including IL-1β, IL-4, IL-6, IL-8, IL-10, TNFα, IFN-γ, IAR-20, COL3A1, laminin, and MCP-1) by reducing NF-κB pathway activation and AT immune cell infiltration. JAZF1 reduces lipid accumulation by regulating the liver X receptor response element (LXRE) of the SREBP-1c promoter, the cAMP-response element (CRE) of HMGCR, and the TR4 axis. LXRE and CRE sites are present in many cytokine and lipid metabolism gene promoters, which suggests that JAZF1 regulates these genes through these sites. NF-κB is the center of the JAZF1-mediated inhibition of the inflammatory response. JAZF1 suppresses NF-κB expression by suppressing TAK1 expression. Interestingly, TAK1 inhibition also decreases lipid accumulation. A dual-targeting strategy of NF-κB and TAK1 could inhibit both inflammation and lipid accumulation. Dual-target compounds (including prodrugs) 1-5 exhibit nanomolar inhibition by targeting NF-κB and TAK1, EGFR, or COX-2. However, the NF-κB suppressing activity of these compounds is relatively low (IC50 > 300 nM). Compounds 6-14 suppress NF-κB expression with IC50 values ranging from 1.8 nM to 38.6 nM. HS-276 is a highly selective, orally bioavailable TAK1 inhibitor. Combined structural modifications of compounds using a prodrug strategy may enhance NF-κB inhibition. This review focused on the role and mechanism of JAZF1 in inflammation and lipid accumulation for the identification of new anti-atherosclerotic targets.

Variants in JAZF1 are associated with asthma, type 2 diabetes, and height in the United Kingdom biobank population

Background: Asthma, type 2 diabetes (T2D), and anthropometric measures are correlated complex traits that all have a major genetic component. Objective: To investigate the overlap in genetic variants associated with these complex traits. Methods: Using United Kingdom Biobank data, we performed univariate association analysis, fine-mapping, and mediation analysis to identify and dissect shared genomic regions associated with asthma, T2D, height, weight, body mass index (BMI), and waist circumference (WC). Results: We found several genome-wide significant variants in and around the JAZF1 gene that are associated with asthma, T2D, or height with two of these variants shared by the three phenotypes. We also observed an association in this region with WC when adjusted for BMI. However, there was no association with WC when it was not adjusted for BMI or weight. Additionally, only suggestive associations between variants in this region and BMI were observed. Fine-mapping analyses suggested that within JAZF1 there are non-overlapping regions harboring causal susceptibility variants for asthma, T2D, and height. Mediation analyses supported the conclusion that these are independent associations. Conclusion: Our findings indicate that variants in the JAZF1 are associated with asthma, T2D, and height, but the associated causal variant(s) are different for each of the three phenotypes.

Structures of human TR4LBD-JAZF1 and TR4DBD-DNA complexes reveal the molecular basis of transcriptional regulation

Testicular nuclear receptor 4 (TR4) modulates the transcriptional activation of genes and plays important roles in many diseases. The regulation of TR4 on target genes involves direct interactions with DNA molecules via the DNA-binding domain (DBD) and recruitment of coregulators by the ligand-binding domain (LBD). However, their regulatory mechanisms are unclear. Here, we report high-resolution crystal structures of TR4DBD, TR4DBD-DNA complexes and the TR4LBD-JAZF1 complex. For DNA recognition, multiple factors come into play, and a specific mutual selectivity between TR4 and target genes is found. The coactivators SRC-1 and CREBBP can bind at the interface of TR4 originally occupied by the TR4 activation function region 2 (AF-2); however, JAZF1 suppresses the binding through a novel mechanism. JAZF1 binds to an unidentified surface of TR4 and stabilizes an α13 helix never reported in the nuclear receptor family. Moreover, the cancer-associated mutations affect the interactions and the transcriptional activation of TR4 in vitro and in vivo, respectively. Overall, our results highlight the crucial role of DNA recognition and a novel mechanism of how JAZF1 reinforces the autorepressed conformation and influences the transcriptional activation of TR4, laying out important structural bases for drug design for a variety of diseases, including diabetes and cancers.

JAZF1: A Metabolic Regulator of Sensitivity to a Polyamine-Targeted Therapy

Identifying and leveraging unique points of metabolic dysregulation in different disease settings is vital for safe and effective incorporation of metabolism-targeted therapies in the clinic. In addition, it has been shown identification of master metabolic transcriptional regulators (MMTR) of individual metabolic pathways, and how they relate to the disease in question, may offer the key to understanding therapeutic response. In prostate cancer, we have previously demonstrated polyamine biosynthesis and the methionine cycle were targetable metabolic vulnerabilities. However, the MMTRs of these pathways, and how they affect treatment, have yet to be explored. We sought to characterize differential sensitivity of prostate cancer to polyamine- and methionine-targeted therapies by identifying novel MMTRs. We began by developing a gene signature from patient samples, which can predict response to metabolic therapy, and further uncovered a MMTR, JAZF1. We characterized the effects of JAZF1 overexpression on prostate cancer cells, basally and in the context of treatment, by assessing mRNA levels, proliferation, colony formation capability, and key metabolic processes. Lastly, we confirmed the relevance of our findings in large publicly available cohorts of prostate cancer patient samples. We demonstrated differential sensitivity to polyamine and methionine therapies and identified JAZF1 as a MMTR of this response.

IMPLICATIONS

We have shown JAZF1 can alter sensitivity of cells and its expression can segregate patient populations into those that do, or do not highly express polyamine genes, leading to better prediction of response to a polyamine targeting therapy.

JAZF1: A metabolic actor subunit of the NuA4/TIP60 chromatin modifying complex

The multisubunit NuA4/TIP60 complex is a lysine acetyltransferase, chromatin modifying factor and gene co-activator involved in diverse biological processes. The past decade has seen a growing appreciation for its role as a metabolic effector and modulator. However, molecular insights are scarce and often contradictory, underscoring the need for further mechanistic investigation. A particularly exciting route emerged with the recent identification of a novel subunit, JAZF1, which has been extensively linked to metabolic homeostasis. This review summarizes the major findings implicating NuA4/TIP60 in metabolism, especially in light of JAZF1 as part of the complex.

Interplay Between GH-regulated, Sex-biased Liver Transcriptome and Hepatic Zonation Revealed by Single-Nucleus RNA Sequencing

The zonation of liver metabolic processes is well-characterized; however, little is known about the cell type-specificity and zonation of sexually dimorphic gene expression or its growth hormone (GH)-dependent transcriptional regulators. We address these issues using single-nucleus RNA-sequencing of 32 000 nuclei representing 9 major liver cell types. Nuclei were extracted from livers from adult male and female mice; from males infused with GH continuously, mimicking the female plasma GH pattern; and from mice exposed to TCPOBOP, a xenobiotic agonist ligand of the nuclear receptor CAR that perturbs sex-biased gene expression. Analysis of these rich transcriptomic datasets revealed the following: 1) expression of sex-biased genes and their GH-dependent transcriptional regulators is primarily restricted to hepatocytes and is not a feature of liver nonparenchymal cells; 2) many sex-biased transcripts show sex-dependent zonation within the liver lobule; 3) gene expression is substantially feminized both in periportal and pericentral hepatocytes when male mice are infused with GH continuously; 4) sequencing nuclei increases the sensitivity for detecting thousands of nuclear-enriched long-noncoding RNAs (lncRNAs) and enables determination of their liver cell type-specificity, sex-bias and hepatocyte zonation profiles; 5) the periportal to pericentral hepatocyte cell ratio is significantly higher in male than female liver; and 6) TCPOBOP exposure disrupts both sex-specific gene expression and hepatocyte zonation within the liver lobule. These findings highlight the complex interconnections between hepatic sexual dimorphism and zonation at the single-cell level and reveal how endogenous hormones and foreign chemical exposure can alter these interactions across the liver lobule with large effects both on protein-coding genes and lncRNAs.

Identification of Homozygous Regions With Adverse Effects on the Five Economic Traits of Duroc Pigs

Runs of homozygosity (ROH) are widely used to estimate genomic inbreeding, which is linked to inbreeding depression on phenotypes. However, the adverse effects of specific homozygous regions on phenotypic characteristics are rarely studied in livestock. In this study, the 50 K SNP data of 3,770 S21 Duroc (American origin) and 2,096 S22 Duroc (Canadian origin) pigs were used to investigate the harmful ROH regions on five economic traits. The results showed that the two Duroc lines had different numbers and distributions of unfavorable ROHs, which may be related to the different selection directions and intensities between the two lines. A total of 114 and 58 ROH segments were found with significant adverse effects on the economic traits of S21 and S22 pigs, respectively. Serval pleiotropic ROHs were detected to reduce two or multiple phenotypic performances in two Duroc populations. Candidate genes in these shared regions were mainly related to growth, fertility, immunity, and fat deposition. We also observed that some ROH genotypes may cause opposite effects on different traits. This study not only enhances our understanding of the adverse effects of ROH on phenotypes, but also indicates that ROH information could be incorporated into breeding programs to estimate and control the detrimental effects of homozygous regions.

Cis-regulation of antisense noncoding RNA at the JAZF1 locus in type 2 diabetes

BACKGROUND

Several genomic loci of type 2 diabetes (T2D) nominated in genome-wide association studies (GWASs) have been suggested to regulate metabolism in muscle. However, a large portion of the genetic risk and the underlying regulation remain unexplained. This study aimed to localize the potentially functional regions or genes at juxtaposed with another zinc finger protein 1 (JAZF1) locus and interpret their possible biological mechanisms in the muscle of T2D.

METHODS AND RESULTS

With a cross-population meta-analysis of 7 GWASs, we identified a linkage disequilibrium (LD) block within intron 1 of JAZF1 that was significantly associated with T2D (FDR < 0.05). The colocalization analysis showed a significant association between genetically determined expression of JAZF1 in skeletal muscle and T2D with a strong probability of colocalization (PP4=75.09%). This region also encodes the upstream regulatory region (URR) of the antisense noncoding RNA JAZF1-AS1. Expression-QTL (e-QTL) analysis detected a regulatory SNP within this LD block, rs864745, that is associated with the expression of JAZF1-AS1 and JAZF1. With in vitro cloning, we further reported the role of JAZF1-AS1 in cis-regulating JAZF1 by directly forming RNA double strands. Downregulation of JAZF1, caused by JAZF1-AS1 depletion, inhibited the glucose uptake and lipid oxidation in skeletal muscle.

CONCLUSIONS

This study proposes a strategy to identify a novel T2D gene at the reported locus and generated a model in which polymorphisms at JAZF1 influence T2D risk through antisense-mediated gene regulation.

Rs864745 in JAZF1, an Islet Function Associated Variant, Correlates With Plasma Lipid Levels in Both Type 1 and Type 2 Diabetes Status, but Not Healthy Subjects

OBJECTIVE

This study aims to reveal the association between JAZF1 rs864745 A>G variant and type 2 diabetes (T2D), type 1 diabetes (T1D) risk, and their correlation with clinical features, including islet function, islet autoimmunity, and plasma lipid levels.

METHODS

We included 2505 healthy controls based on oral glucose tolerance test (OGTT), 1736 unrelated T2D, and 1003 unrelated autoantibody-positive T1D individuals. Binary logistic regression was performed to evaluate the relationships between rs864745 in JAZF1 and T2D, T1D, and islet-specific autoantibody status under the additive model, while multiple linear regression was used to assess its effect on glycemic-related quantitative traits and plasma lipid levels.

RESULTS

We did not find any association between rs864745 in JAZF1 and T2D, T1D, or their subgroups (All P > 0.05). For glycemic traits, we found that the G allele of this variant was significantly associated with higher 120 min insulin level, insulinogenic index (IGI), corrected insulin response (CIR), and acute insulin response (BIGTT-AIR) (P = 0.033, 0.006, 0.009, and 0.016, respectively) in healthy individuals. Similar associations were observed in newly diagnosed T2D but not T1D individuals. Although this variant had no impact on islet autoimmunity (All P > 0.05), significant associations with plasma total cholesterol (TC) and low-density lipoprotein (LDL) level stratified by JAZF1 rs864745 variant were observed in the disease status of T2D (P = 0.002 and 0.003) and T1D (P = 0.024 and 0.009), with significant heterogeneity to healthy individuals.

CONCLUSIONS

The common JAZF1 rs864745 variant contributes to islet function and lipid metabolism, which might be put into genetic risk scores to assess the risk of related clinical features.

JAZF1 heterozygous knockout mice show altered adipose development and metabolism

BACKGROUND

Juxtaposed with another zinc finger protein 1 (JAZF1) is associated with metabolic disorders, including type 2 diabetes mellitus (T2DM). Several studies showed that JAZF1 and body fat mass are closely related. We attempted to elucidate the JAZF1 functions on adipose development and related metabolism using in vitro and in vivo models.

RESULTS

The JAZF1 expression was precisely regulated during adipocyte differentiation of 3T3-L1 preadipocyte and mouse embryonic fibroblasts (MEFs). Homozygous JAZF1 deletion (JAZF1-KO) resulted in impaired adipocyte differentiation in MEF. The JAZF1 role in adipocyte differentiation was demonstrated by the regulation of PPARγ-a key regulator of adipocyte differentiation. Heterozygous JAZF1 deletion (JAZF1-Het) mice fed a normal diet (ND) or a high-fat diet (HFD) had less adipose tissue mass and impaired glucose homeostasis than the control (JAZF1-Cont) mice. However, other metabolic organs, such as brown adipose tissue and liver, were negligible effect on JAZF1 deficiency.

CONCLUSION

Our findings emphasized the JAZF1 role in adipocyte differentiation and related metabolism through the heterozygous knockout mice. This study provides new insights into the JAZF1 function in adipose development and metabolism, informing strategies for treating obesity and related metabolic disorders.

Jazf1 acts as a regulator of insulin-producing β-cell differentiation in induced pluripotent stem cells and glucose homeostasis in mice

Genetic susceptibility of type 2 diabetes and Juxtaposed with another zinc finger protein 1 (Jazf1) has been reported; however, the precise role of Jazf1 in metabolic processes remains elusive. In this study, using Jazf1-knockout (KO)-induced pluripotent stem cells (iPSC), pancreatic beta cell line MIN6 cells, and Jazf-1 heterozygous KO (Jazf1^+/- ) mice, the effect of Jazf1 on gradual differentiation was investigated. We checked the alterations of the genes related with β-cell specification, maturation, and insulin release against glucose treatment by the gain and loss of the Jazf1 gene in the MIN6 cells. Because undifferentiated Jazf1-KO iPSC were not significantly different from wild-type (WT) iPSC, the size and endoderm marker expression after embryoid body (EB) and teratoma formation were investigated. Compared to EB and teratomas formed with WT iPSC, the EB and teratomas from with Jazf1-KO iPSC were smaller, and in teratomas, the expression of proliferation markers was reduced. Moreover, the expression of the gene sets for β-cell differentiation and the levels of insulin and C-peptide secreted by insulin precursor cells were notably reduced in β-cells differentiated from Jazf1-KO iPSC compared with those differentiated from WT iPSC. A comparison of Jazf1^+/- and WT mice showed that Jazf1^+/- mice had lower levels of serum insulin, pancreatic insulin expression, and decreased pancreatic β-cell size, which resulted in defects in the glucose homeostasis. These findings suggest that Jazf1 plays a pivotal role in the differentiation of β-cells and glucose homeostasis.

Antiobesity Effect of Novel Probiotic Strains in a Mouse Model of High-Fat Diet-Induced Obesity

Obesity is one of the major causes of the development of metabolic diseases, particularly cardiovascular diseases and type-2 diabetes mellitus. Increased lipid accumulation and abnormal adipocyte growth, which is an increase in cell numbers and differentiation, have been documented as major pathological characteristics of obesity. Thus, the inhibition of adipogenic differentiation prevents and suppresses obesity. Recently, specific probiotic strains have been known to regulate lipid metabolism in vitro and/or in vivo. Previously, we demonstrated that Lactobacillus johnsonni 3121 and Lactobacillus rhamnosus 86 could act as novel probiotic strains and reduce cholesterol levels. Moreover, both strains significantly reduced lipid accumulation and inhibited adipocyte differentiation by downregulating the adipogenic transcription factor in 3T3-L1 adipocytes. Therefore, L. johnsonni 3121 and L. rhamnosus 86 were selected for in vivo evaluation of their anti-obesity effects using a high-fat diet-induced obese mouse model. Daily oral administration of L. johnsonni 3121 and L. rhamnosus 86 for 12 weeks significantly improved serum lipid profile and downregulated the expression of genes related to adipogenesis and lipogenesis in epididymal white adipose tissue of high-fat diet fed obese mice (p < 0.05). Fecal analysis also suggested that the two probiotic strains could normalize the altered obesity-related gut microbiota in high-fat diet-fed obese mice. These results collectively demonstrate that oral administration of L. johnsonni 3121 and L. rhamnosus 86 could prevent obesity, thereby improving metabolic health.

GWA-based pleiotropic analysis identified potential SNPs and genes related to type 2 diabetes and obesity

Metabolic syndrome is a cluster of symptoms including excessive body fat and insulin resistance which may lead to obesity and type 2 diabetes (T2D). The physiological and pathological cross-talk between T2D and obesity is crucial and complex, meanwhile, the genetic connection between T2D and obesity is largely unknown. The purpose of this study is to identify pleiotropic SNPs and genes between these two associated conditions by applying genetic analysis incorporating pleiotropy and annotation (GPA) on two large genome-wide association studies (GWAS) data sets: a body mass index (BMI) data set containing 339,224 subjects and a T2D data set containing 110,452 subjects. In all, 5182 SNPs showed pleiotropy in both T2D and obesity. After further prioritization based on suggested local false discovery rates (FDR) by the GPA model, 2146 SNPs corresponding to 217 unique genes are significantly associated with both traits (FDR < 0.2), among which 187 are newly identified pleiotropic genes compare with original GWAS in individual traits. Subsequently, gene enrichment and pathway analyses highlighted several pleiotropic SNPs including rs849135 (FDR = 0.0002), rs2119812 (FDR = 0.0018), rs4506565 (FDR = 1.23E-08), rs1558902 (7.23E-10) and corresponding genes JAZF1, SYN2, TCF7L2, FTO which may play crucial rol5es in the etiology of both T2D and obesity. Additional evidences from expression data analysis of pleiotropic genes strongly supports that the pleiotropic genes including JAZF1 (p = 1.39E-05 and p = 2.13E-05), SYN2 (p = 5.49E-03 and p = 5.27E-04), CDKN2C (p = 1.99E-12 and p = 6.27E-11), RABGAP1 (p = 3.08E-03 and p = 7.46E-03), and UBE2E2 (p = 1.83E-04 and p = 8.22E-03) play crucial roles in both obesity and T2D pathogenesis. Pleiotropic analysis integrated with functional network identified several novel and causal SNPs and genes involved in both BMI and T2D which may be ignored in single GWAS.

TFAP2B, AP-1 and JAZF1 Expression in Tissues of Papillary Thyroid Carcinoma Patients; Clinical, Pathological and Prognostic Values

OBJECTIVE

Transcription factor activating protein 2 B (TFAP2 B) is a transcription factor that regulates many steps of embryogenesis, cell growth, apoptosis and recently oncogenesis and cancer progression. AP-1 is a transcription factor that is a downstream molecule of the MAPK signaling pathway. Juxtaposed with zinc finger gene 1 (JAZF1) is a recently detected transforming growth factor which has a role in carcinogenesis. Hence the present study aimed to assess those markers expression in tissues from patients with such cancer correlation their expression with clinic-pathological findings of the tumor and prognostic and follow-up findings of patients.

METHODS

We have collected tissue samples from papillary thyroid cancer patients and adjacent non-neoplastic tissues from 80 patients. We assessed the expression of TFAP2B, AP-1 and JAZF1 using immunohistochemistry.

RESULTS

Expression of TFAP2B was positively associated with lymph nodes metastases (p=0.003), distant metastases (p=0.002), recurrence of the tumor (p=0.002), unfavourable disease-free survival rate (p=0.003). AP-1 expression is positively associated with advanced stage (p=0.002), presence of extra-thyroid invasion (p=0.005), recurrence of the tumor (p=0.005), unfavorable disease-free survival rate (p=0.01). JAZF1 expression is negatively associated with huge tumor size (0.023), vascular invasion (p=0.007) and unfavorable overall survival rate (p=.030).

CONCLUSION

High expression levels of TFAP2B and AP-1 and low expression levels of JAZF1 were associated with unfavourable pathological, prognostic parameters and dismal patient's outcome.<br />.

Hypolipidemic and antioxidant activities of Trichosanthes kirilowii maxim seed oil and flavonoids in mice fed with a high-fat diet

Trichosanlhes kirilowii Maxim seed oil (TSO) is rich in conjugated linolenic acids, and the flavonoids (FLA) combined with n-3 fatty acids can effectively change the plasma antioxidant capacity. Hyperlipidemia and oxidative stress are one of the most important risk factors for cardiovascular disease. This study aims to evaluate the effect of the TSO, FLA, and TSO combined with FLA (TSOFLA) intake on hyperlipemia mice. TSO and TSOFLA administration resulted in a significant decline in serum levels of total cholesterol, triglycerides, and low density lipoprotein-cholesterol. TSOFLA improved the hepatic and serum antioxidant status as assessed by superoxide dismutase, glutathione peroxidase activities, and reduced the levels of lipid peroxidation. Hematoxylin-eosin staining of liver and aorta tissue has shown a marked reduction of the hyperlipidemia-induced lesions by gavage TSOFLA. Compared with TSO and FLA, TSOFLA has more significant hypolipidemic and antioxidant activities, which effects may be correlated to the synergy between TSO and FLA. PRACTICAL APPLICATIONS: Dyslipidemia is a common metabolic disorder, which is characterized by triglyceride levels increased, total cholesterol, and low-density lipoprotein cholesterol. Lipid-lowering treatment can reduce the expansion of coronary atherosclerosis, and particular the dietary lipids have important roles in controlling the concentrations of these risk factors. This is the first study evaluating the hypolipidemic and antioxidant activities effects of Trichosanlhes kirilowii Maxim seed oil (TSO), flavonoids (FLA), and TSO combined with FLA (TSOFLA) intake on hyperlipemia mice caused by a high-fat diet. The pharmacological effects of dietary TSOFLA are correlated to its high content of unsaturated fatty acids and flavonoids. This information can be of interest to the development of food supplements in the field of diseases associated with high-fat intakes such as cardiovascular diseases and adiposis.

Effect of central JAZF1 on glucose production is regulated by the PI3K-Akt-AMPK pathway

The role of central juxtaposed with another zinc finger gene 1 (JAZF1) in glucose regulation remains unclear. Here, we activated mediobasal hypothalamus (MBH) JAZF1 in high-fat diet (HFD)-fed rats by an adenovirus expressing JAZF1 (Ad-JAZF1). We evaluated the changes in the hypothalamic insulin receptor (InsR)-PI3K-Akt-AMPK pathway and hepatic glucose production (HGP). To investigate the impact of MBH Ad-JAZF1 on HGP, we activated MBH JAZF1 in the presence or absence of ATP-dependent potassium (K_ATP ) channel inhibition, hepatic branch vagotomy (HVG), or an AMPK activator (AICAR). In HFD-fed rats, MBH Ad-JAZF1 decreased body weight and food intake, and inhibited HGP by increasing hepatic insulin signaling. Under insulin stimulation, MBH Ad-JAZF1 increased InsR and Akt phosphorylation, and phosphatidylinositol 3, 4, 5-trisphosphate (PIP3) formation; however, AMPK phosphorylation was decreased in the hypothalamus. The positive effect of MBH JAZF1 on hepatic insulin signaling and HGP was prevented by treatment with a K_ATP channel inhibitor or HVG. The metabolic impact of hypothalamic JAZF1 was also blocked by MBH AICAR. Ad-JAZF1 treatment in SH-SY5Y cells resulted in an elevation of InsR and Akt phosphorylation following insulin stimulation. Our findings show that hypothalamic JAZF1 regulates HGP via the InsR-PI3K-Akt-AMPK pathway and K_ATP channels.

Computational and functional analyses of T2D GWAS SNPs for transcription factor binding

Genome-wide association studies (GWASs) have successfully identified numerous non-coding genetic variants for type 2 diabetes (T2D), but the functional roles underlying these non-coding variants remain largely unknown. The effects of T2D GWAS lead SNPs on transcriptional factors binding motifs were firstly analyzed via JASPAR, followed by functional validations including dual-luciferase reporter assays, biotin-based DNA pull-down assays, real-time quantitative PCR, and western blotting. The results showed that GWAS SNP rs4430796 conferred T allele specific transcriptional enhancer activity via a PAX6 binding element, and upregulated the expression of HNF1B. GWAS SNP rs4607103 showed a bidirectional modulation of ADAMTS9-AS2 and ADAMTS9 by TCF7L2 in a T allele-specific manner. GWAS SNP rs849135 conferred C allele-specific bidirectional transcriptional enhancer activity via a CREB1 binding element. Our findings have uncovered the functional mechanisms of three T2D GWAS SNPs via affecting the binding of transcription factors, providing new insights into the genetics and molecular pathogenesis of T2D.

JAZF1 Suppresses Papillary Thyroid Carcinoma Cell Proliferation and Facilitates Apoptosis via Regulating TAK1/NF-κB Pathways

Purpose

Juxtaposed with another zinc finger gene 1 (JAZF1) is involved in gluconeogenesis, insulin sensitivity, cell differentiation, lipid metabolism and inflammation, but its role in carcinoma remains inexplicit.

Patients and methods

We explored the JAZF1 expression in human papillary thyroid cancer (PTC) tissues, adjacent normal thyroid tissues and nodular goitre tissues, as well as Ki67 expression in PTC tissues, using immunohistochemistry staining. Western blotting and RT-qPCR were performed to explore the JAZF1 expression levels in Nthy-ori 3–1, BCPAP and TPC-1 cells. BCPAP cells overexpressing JAZF1 were constructed using an Adv-JAZF1-GFP recombinant adenovirus vector. Next, the cell proliferation assay, colony formation assay, cell cycle analysis, apoptosis and immunofluorescence were performed. The mRNA expression level of nuclear factor-κB p65 (NF-κB p65) was examined using RT-qPCR. The expression of Bcl-2, Bax, transforming growth factor beta-activated kinase 1 (TAK1), NF-κB p65 and NF-κB p-p65 were examined using Western blotting.

Results

The expression of JAZF1 in human PTC tissues was downregulated compared with adjacent thyroid tissues or nodular goitre. Additionally, JAZF1 expression was associated with the location and lymph node metastasis of PTC. The expression level of JAZF1 had a negative correlation with Ki67 labelling index (LI). Compared to Nthy-ori 3–1 cells and TPC-1 cells, BCPAP cells expressed the lowest JAZF1. JAZF1 overexpressed significantly inhibited proliferation, caused G0/G1 cell cycle arrest and promoted apoptosis in BCPAP cells. Furthermore, JAZF1 overexpressed in BCPAP cells clearly upregulated the expression level of Bax protein, whereas decreased the expression of Bcl-2, TAK1, NF-κB but did not affect the mRNA or protein expression level of NF-κB p65.

Conclusion

JAZF1 inhibits proliferation and induces apoptosis in BCPAP cells by suppressing the activation of TAK1/NF-κB signalling pathways, suggesting that JAZF1 may serve as a reliable molecular marker in PTC.

Breed, Diet, and Interaction Effects on Adipose Tissue Transcriptome in Iberian and Duroc Pigs Fed Different Energy Sources

In this study, we analyzed the effects of breed, diet energy source, and their interaction on adipose tissue transcriptome in growing Iberian and Duroc pigs. The study comprised 29 Iberian and 19 Duroc males, which were kept under identical management conditions except the nutritional treatment. Two isoenergetic diets were used with 6% high oleic sunflower oil (HO) or carbohydrates (CH) as energy sources. All animals were slaughtered after 47 days of treatment at an average live weight of 51.2 kg. Twelve animals from each breed (six fed each diet) were employed for ham subcutaneous adipose tissue RNA-Seq analysis. The data analysis was performed using two different bioinformatic pipelines. We detected 837 and 1456 differentially expressed genes (DEGs) according to breed, depending on the pipeline. Due to the strong effect of breed on transcriptome, the effect of the diet was separately evaluated in the two breeds. We identified 207 and 57 DEGs depending on diet in Iberian and Duroc pigs, respectively. A joint analysis of both effects allowed the detection of some breed–diet interactions on transcriptome, which were inferred from RNA-Seq and quantitative PCR data. The functional analysis showed the enrichment of functions related to growth and tissue development, inflammatory response, immune cell trafficking, and carbohydrate and lipid metabolism, and allowed the identification of potential regulators. The results indicate different effects of diet on adipose tissue gene expression between breeds, affecting relevant biological pathways.

JAZF1, a relevant metabolic regulator in type 2 diabetes

Excessive adiposity and metabolic inflammation are the key risk factors of type 2 diabetes mellitus (T2DM). Juxtaposed with another zinc finger gene 1 (JAZF1) has been identified as a novel transcriptional cofactor, with function of regulating glucose and lipid homeostasis and inflammation. JAZF1 is involved in metabolic process of T2DM via interaction with several nuclear receptors and protein kinases. Additionally, increasing evidence from genome-wide association studies (GWAS) has shown that JAZF1 polymorphisms are closely associated with T2DM. In this review, we have updated the latest research advances on JAZF1 and discussed its regulatory network in T2DM. The association between JAZF1 polymorphisms and T2DM is discussed as well. The information provided is of importance for guiding future studies as well as for the design of JAZF1-based T2DM therapy.

Di(2-ethylhexyl)phthalate induces reproductive toxicity via JAZF1/TR4 pathway and oxidative stress in pubertal male rats

Di(2-ethylhexyl)phthalate (DEHP) is a typical endocrine-disrupting chemical and reproductive toxicant. Although previous studies have attempted to describe the mechanism by which DEHP exposure results in reproductive dysfunction, few studies focused on puberty, a critical period of reproductive development, and the increased susceptibility to injury in adolescents. To elucidate the mechanism underpinning the testicular effects of DEHP in puberty, we sought to investigate the JAZF1/TR4 pathway in the testes of pubertal rats. Specifically, we focused on the role of the JAZF1/TR4 pathway in male reproduction, including the genes JAZF1, TR4, Sperm 1, and Cyclin A1. In the present study, rats were exposed to increasing concentrations of DEHP (0, 250, 500, and 1000 mg/kg/day) by oral gavages for 30 days. Then we assayed testicular zinc and oxidative stress levels. Our results indicated that DEHP exposure could lead to oxidative stress and decrease the contents of testicular zinc. Additionally, significant morphological changes and cell apoptosis were observed in testes exposed to DEHP, as identified by hematoxylin and eosin staining and the terminal deoxynucleotidyl transferase-mediated nick and labeling assay. By measuring the expression levels of the above relevant genes by qPCR, we found the DEHP-induced increased expression of JAZF1 and decreased expression of TR4, Sperm 1, and Cyclin A1. Therefore, we have demonstrated that in vivo exposure to DEHP might induce reproductive toxicity in pubertal male rats through the JAZF1/TR4 pathway and oxidative stress.

JAZF1 ameliorates age and diet-associated hepatic steatosis through SREBP-1c -dependent mechanism

JAZF zinc finger 1 (JAZF1) is involved in glucose and lipid metabolisms. However, its role in aging- and nutrient-related hepatic steatosis is unclear. In the current study, we demonstrated that JAZF1 expression was markedly down-regulated in obesity-associated mice and nonalcoholic fatty liver disease (NAFLD) patients. During aging, JAZF1 expression was gradually down-regulated in both C57BL/6 J and JAZF1-Tg mice. In JAZF1-Tg mice, body fat content and hepatosteatosis were protected from HFD-induced steatosis, and accompanied by decreased lipogenesis gene expression. The inhibitory effects of hepatic steatosis in JAZF1-Tg mice, however, were disappeared during aging. In hepatocytes, over-expression of JAZF1 attenuated, while knockdown of JAZF1 enhanced the expression of lipogenesis genes. The over-expressing of JAZF1 in hepatocytes displayed the increased adenosine monophosphate-activated protein kinase (AMPK) phosphorylation and decreased sterol regulatory element-binding protein 1c (SREBP-1c) expression. The roles of JAZF1 were partially attenuated by Compound C. Mechanistically, JAZF1 suppressed SREBP-1c expression through the inhibition of transcriptional activity of liver X receptor response elements (LXREs) in the SREBP-1c promoter. Data illustrate that JAZF1 may have a crucial role in the regulation of age and nutrient-associated hepatosteatosis through an AMPK/SREBP-1c-dependent mechanism.

JAZF1 Inhibits Adipose Tissue Macrophages and Adipose Tissue Inflammation in Diet-Induced Diabetic Mice

Background

Juxtaposed with another zinc finger gene 1 (JAZF1) affects gluconeogenesis, insulin sensitivity, lipid metabolism, and inflammation, but its exact role in chronic inflammation remains unclear. This study aimed to examine JAZF1 overexpression in vivo on adipose tissue macrophages (ATMs).

Methods

Mouse models of high-fat diet- (HFD-) induced insulin resistance were induced using C57BL/6J and JAZF1-overexpressing (JAZF1-OX) mice. The mice were randomized (8–10/group) to C57BL/6J mice fed regular diet (RD) (NC group), C57BL/6J mice fed HFD (HF group), JAZF1-OX mice fed RD (NJ group), and JAZF1-OX mice fed HFD (HJ group). Adipose tissue was harvested 12 weeks later. ATMs were evaluated by flow cytometry. Inflammatory markers were evaluated by ELISA.

Results

JAZF1-OX mice had lower blood lipids, blood glucose, body weight, fat weight, and inflammatory markers compared with HF mice (all P < 0.05). JAZF1 overexpression decreased ATM number and secretion of proinflammatory cytokines. JAZF1 overexpression decreased total CD4+ T cells, active T cells, and memory T cells and increased Treg cells. JAZF1 overexpression downregulated IFN-γ and IL-17 levels and upregulated IL-4 levels. JAZF1 overexpression decreased MHCII, CD40, and CD86 in total ATM, CD11c+ ATM, and CD206+ ATM.

Conclusions

JAZF1 limits adipose tissue inflammation by limiting macrophage populations and restricting their antigen presentation function.

Jazf1 promotes prostate cancer progression by activating JNK/Slug

Juxtaposed with another zinc finger protein 1 (Jazf1) is a zinc finger protein and is known to affect both prostate cancer and type 2 diabetes. Jazf1 inhibits testicular nuclear receptor 4 (TR4) activation through protein-protein interaction, which results in weight loss and alleviates diabetes. However, the role of Jazf1 in prostate cancer is still poorly understood. Hence, we investigated whether the expression of Jazf1 is associated with prostate cancer progression. We confirmed the upregulation of Jazf1 expression in human prostate tissue samples. In addition, using Jazf1 overexpressing prostate cancer cell lines, DU145 and LNCaP, we found Jazf1 promoted cell proliferation and colony formation ability. We also observed that Jazf1 dramatically enhanced cell migration and invasion in transwell assays. Additionally, we checked the upregulation of vimentin and downregulation of E-cadherin expression in Jazf1-overexpressing DU145 and LNCaP cells. Moreover, we found that Slug, which is known to be regulated by JNK/c-Jun phosphorylation, was upregulated in the microarray analysis of two prostate cancer cell lines. Jazf1 promotes the phosphorylation of JNK/c-Jun, likely promoting cell proliferation and invasion through Slug. In a xenograft model, tumors overexpressing Jazf1 were larger than control tumors, and tumors with decreased Jazf1 were smaller. These data indicated that Jazf1 enhances prostate cancer progression and metastasis via regulating JNK/Slug signaling. Taken together, these results suggest that Jazf1 plays an important role in both androgen dependent and independent prostate cancer.

Serum amyloid A1 levels and amyloid deposition following a high-fat diet challenge in transgenic mice overexpressing hepatic serum amyloid A1

Serum amyloid A (SAA) is an acute-phase response protein in the liver, and SAA1 is the major precursor protein involved in amyloid A amyloidosis. This amyloidosis has been reported as a complication in chronic inflammatory conditions such as arthritis, lupus, and Crohn's disease. Obesity is also associated with chronic, low-grade inflammation and sustained, elevated levels of SAA1. However, the contribution of elevated circulating SAA1 to metabolic disturbances and their complications is unclear. Furthermore, in several recent studies of transgenic (TG) mice overexpressing SAA1 that were fed a high-fat diet (HFD) for a relatively short period, no relationship was found between SAA1 up-regulation and metabolic disturbances. Therefore, we generated TG mice overexpressing SAA1 in the liver, challenged these mice with an HFD, and investigated the influence of elevated SAA1 levels. Sustained, elevated levels of SAA1 were correlated with metabolic parameters and local cytokine expression in the liver following 16 weeks on the HFD. Moreover, prolonged consumption (52 weeks) of the HFD was associated with impaired glucose tolerance and elevated SAA1 levels and resulted in systemic SAA1-derived amyloid deposition in the kidney, liver, and spleen of TG mice. Thus, we concluded that elevated SAA1 levels under long-term HFD exposure result in extensive SAA1-derived amyloid deposits, which may contribute to the complications associated with HFD-induced obesity and metabolic disorders.

RNA-Seq reveals common and unique PXR- and CAR-target gene signatures in the mouse liver transcriptome

The pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are well-known xenobiotic-sensing nuclear receptors with overlapping functions. However, there lacks a quantitative characterization to distinguish between the PXR and CAR target genes and signaling pathways in the liver. The present study performed a transcriptomic comparison of the PXR- and CAR-targets using RNA-Seq in livers of adult wild-type mice that were treated with the prototypical PXR ligand PCN (200mg/kg, i.p. once daily for 4days in corn oil) or the prototypical CAR ligand TCPOBOP (3mg/kg, i.p., once daily for 4days in corn oil). At the given doses, TCPOBOP differentially regulated many more genes (2125) than PCN (212), and 147 of the same genes were differentially regulated by both chemicals. As expected, the top pathways differentially regulated by both PCN and TCPOBOP were involved in xenobiotic metabolism, and they also up-regulated genes involved in retinoid metabolism, but down-regulated genes involved in inflammation and iron homeostasis. Regarding unique pathways, PXR activation appeared to overlap with the aryl hydrocarbon receptor signaling, whereas CAR activation appeared to overlap with the farnesoid X receptor signaling, acute-phase response, and mitochondrial dysfunction. The mRNAs of differentially regulated drug-processing genes (DPGs) partitioned into three patterns, namely TCPOBOP-induced, PCN-induced, as well as TCPOBOP-suppressed gene clusters. The cumulative mRNAs of the differentially regulated DPGs, phase-I and -II enzymes, as well as efflux transporters were all up-regulated by both PCN and TCPOBOPOP, whereas the cumulative mRNAs of the uptake transporters were down-regulated only by TCPOBOP. The absolute mRNA abundance in control and receptor-activated conditions was examined in each DPG category to predict the contribution of specific DPG genes in the PXR/CAR-mediated pharmacokinetic responses. The preferable differential regulation by TCPOBOP in the entire hepatic transcriptome correlated with a marked change in the expression of many DNA and histone epigenetic modifiers. In conclusion, the present study has revealed known and novel, as well as common and unique targets of PXR and CAR in mouse liver following pharmacological activation using their prototypical ligands. Results from this study will further support the role of these receptors in regulating the homeostasis of xenobiotic and intermediary metabolism in the liver, and aid in distinguishing between PXR and CAR signaling at various physiological and pathophysiological conditions. This article is part of a Special Issue entitled: Xenobiotic nuclear receptors: New Tricks for An Old Dog, edited by Dr. Wen Xie.

Hepatocellular carcinoma and non-alcoholic steatohepatitis: The state of play

Hepatocellular carcinoma (HCC) is now the fifth cancer of greatest frequency and the second leading cause of cancer related deaths worldwide. Chief amongst the risks of HCC are hepatitis B and C infection, aflatoxin B1 ingestion, alcoholism and obesity. The latter can promote non-alcoholic fatty liver disease (NAFLD), that can lead to the inflammatory form non-alcoholic steatohepatitis (NASH), and can in turn promote HCC. The mechanisms by which NASH promotes HCC are only beginning to be characterized. Here in this review, we give a summary of the recent findings that describe and associate NAFLD and NASH with the subsequent HCC progression. We will focus our discussion on clinical and genomic associations that describe new risks for NAFLD and NASH promoted HCC. In addition, we will consider novel murine models that clarify some of the mechanisms that drive NASH HCC formation.

JAZF1 promotes proliferation of C2C12 cells, but retards their myogenic differentiation through transcriptional repression of MEF2C and MRF4-Implications for the role of Jazf1 variants in oncogenesis and type 2 diabetes

Single-nucleotide polymorphisms associated with type 2 diabetes (T2D) have been identified in Jazf1, which is also involved in the oncogenesis of endometrial stromal tumors. To understand how Jazf1 variants confer a risk of tumorigenesis and T2D, we explored the functional roles of JAZF1 and searched for JAZF1 target genes in myogenic C2C12 cells. Consistent with an increase of Jazf1 transcripts during myoblast proliferation and their decrease during myogenic differentiation in regenerating skeletal muscle, JAZF1 overexpression promoted cell proliferation, whereas it retarded myogenic differentiation. Examination of myogenic genes revealed that JAZF1 overexpression transcriptionally repressed MEF2C and MRF4 and their downstream genes. AMP deaminase1 (AMPD1) was identified as a candidate for JAZF1 target by gene array analysis. However, promoter assays of Ampd1 demonstrated that mutation of the putative binding site for the TR4/JAZF1 complex did not alleviate the repressive effects of JAZF1 on promoter activity. Instead, JAZF1-mediated repression of Ampd1 occurred through the MEF2-binding site and E-box within the Ampd1 proximal regulatory elements. Consistently, MEF2C and MRF4 expression enhanced Ampd1 promoter activity. AMPD1 overexpression and JAZF1 downregulation impaired AMPK phosphorylation, while JAZF1 overexpression also reduced it. Collectively, these results suggest that aberrant JAZF1 expression contributes to the oncogenesis and T2D pathogenesis.

Transcription factor TIP27 regulates glucose homeostasis and insulin sensitivity in a PI3-kinase/Akt-dependent manner in mice

BACKGROUND/OBJECTIVES

Juxtaposed with another zinc-finger gene 1 (TIP27 or JAZF1) is a 27-kDa transcription factor, and genome-wide association studies have recently revealed TIP27 to be associated with type 2 diabetes. However, little is known about its role in the regulation of metabolism. In this study, we investigated the effects of TIP27 overexpression on glucose homeostasis and insulin signaling in high-fat diet (HFD)-fed TIP27 transgenic (TIP27-Tg) mice and db/db mice.

METHODS

We assessed the effects of TIP27 overexpression in both TIP27-Tg mice and db/db mice on glucose metabolism and changes in insulin sensitivity during glucose (GTT) and insulin (ITT) tolerance tests. A hyperinsulinemic-euglycemic clamp was performed on TIP27-Tg mice. Real-time quantitative PCR and western blotting were used to assess mRNA and protein expressions.

RESULTS

TIP27 overexpression in TIP27-Tg mice and in db/db mice led to reduced total cholesterol and fasting plasma insulin levels, and enhanced glucose tolerance and insulin sensitivity during GTT and ITT. Hyperinsulinemic-euglycemic clamp experiments demonstrated that HFD-fed TIP27-Tg mice had lower hepatic glucose production and higher insulin sensitivity compared with nontransgenic littermates. In addition, the hepatic expressions of phosphoenolpyruate carboxykinase (PEPCK), glucose-6-phosphatase (G6Pase) mRNAs and proteins were significantly decreased, whereas the phosphorylation of insulin receptor, insulin receptor substrate-1, adenosine monophosphate-activated protein kinase and Akt kinase (Akt) in the liver was significantly increased in HFD-fed TIP27-Tg mice compared with nontransgenic littermates. Adenovirus-mediated TIP27 overexpression in db/db mice also decreased the expression of gluconeogenic genes and increased the phosphorylation of insulin signaling molecules in the liver compared with controls. Finally, LY294002, a phosphatidylinositol 3-kinase (PI3-kinase) inhibitor, abolished the suppressive effect of TIP27 overexpression on PEPCK and G6Pase expression.

CONCLUSIONS

TIP27 has an important role in glucose homeostasis through the regulation of hepatic glucose metabolism and insulin sensitivity. Furthermore, this regulation requires activation of PI3-kinase.

Association of JAZF1 and TSPAN8/LGR5 variants in relation to type 2 diabetes mellitus in a Saudi population

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a chronic and multifactorial disease with a rapidly rising incidence in Saudi Arabia. Various genes including zinc finger protein 1 (JAZF1) and tetraspanin 8/leucine-rich repeat-containing G protein-coupled receptor (TSPAN8/LGR5) have been previously described to be associated with T2DM. This study investigated the association of JAZF1 (rs864745) and TSPAN8 (rs7961581) with T2DM in a Saudi population.

METHODS

Genomic DNA samples from 400 Saudi T2DM patients and 400 healthy controls were genotyped and analyzed using a polymerase chain reaction-restriction fragment length polymorphism method. The difference between the genotype frequencies were carried out with Chi-square test. Odds ratio, 95 % confidence intervals and p values were calculated using multinomial logistic regression. Dominant and recessive models were implemented to show the statistical significances. Analysis of variance was used to compare differences between genotypes for the various parameters.

RESULTS

Distribution frequencies of the AA, AG, and GG genotypes of JAZF1 (rs864745) differed significantly among T2DM patients and healthy controls (p < 0.05). The AG and GG genotypes were independently and significantly associated with a T2DM risk after adjusting for factors such as age, sex, and body mass index [odds ratio (OR) 2.1 (95 % confidence interval (CI) 1.3-3.4); p = 0.002] and [OR 1.9 (95 % CI 1.2-3.1); p = 0.005], respectively. A genotype-based stratification of anthropometric and biochemical data revealed that the AG + GG genotype is associated with waist circumference (p = 0.04) and fasting blood glucose (p = 0.01) and high-density lipoprotein cholesterol levels (p = 0.02). None of the allele or genotype showed the significant association between the T2DM cases and control subjects in rs7961581 polymorphism in TSPAN8/LGR5 gene.

CONCLUSION

The rs864745 variant in JAZF1 gene may act as genetic risk factors for the development of T2DM in a Saudi population.

Association between KIAA0319L, PXK and JAZF1 gene polymorphisms and unexplained recurrent pregnancy loss in Chinese Han couples

KIAA0319L, PXK and JAZF1 gene polymorphisms were investigated to determine whether they conferred susceptibility to unexplained recurrent pregnancy loss (URPL) in a group of Chinese Han patients. Genotyping and sequencing of the single nucleotide polymorphisms (SNP) rs2275247(A/G) in KIAA0319L, rs2176082(C/T) and rs6445975(G/T) in PXK and the rs1635852(C/T) in JAZF1 were carried out in 84 couples with URPL and 102 healthy couples with at least one live birth. Frequencies of the SNP rs2176082(C/T) in PXK gene were significantly different between women with URPL and control women: P < 0.05; OR 95% CI 0.530 (0.287 to 0.979); OR 95% CI 0.482 (0.254 to 0.911) but were not significantly different after Bonferroni correction. The frequencies of the SNP rs2176082(C/T) in PXK gene showed no difference between the husband of a woman with URPL and a control husband: OR 95% CI 1.494 (0.821 to 2.721); OR 95% CI 1.567 (0.841 to 2.921). No statistically significant differences were observed in the distribution of any genotype or allele frequency or any genetic model of the other three SNPs between couples with URPL and control couples. Therefore, the rs2176082(C/T) polymorphism of PXK might play a possible role in the development of URPL in Chinese Han women.