Reference gene selection for real-time quantitative PCR analysis of the mouse uterus in the peri-implantation period

The effect of folic acid supplementation and folate deficiency on embryo implantation

Implantation is a critical stage of pregnancy, which occurs in a short period of interaction between the receptive endometrium and the embryo. Folic acid (FA) is a synthetic derivative of folate and is recommended as a pre-conceptional supplement. However, the impact of different doses of FA supplementation and folate deficiency during the early stages of pregnancy requires further investigation. The aim of this study was to investigate the possible effects of FA supplementation and folate deficiency on expression of Estrogen Receptor Alpha (ER-α), Vascular Endothelial Growth Factor-A (VEGFA), and Integrin alpha V and beta3 (Integrin αVβ3). A total of 32, 6-8-week old Wistar albino rats were divided into four groups of control, folate-deficiency, low-dose, and high-dose FA supplement groups. After five weeks of FA supplementation and folate deficiency model formation, mated rats were sacrificed on the 5th gestational day (GD), and implantation sites were collected. The expression of ER- α, VEGFA, and Integrin αVβ3 in the implantation sites were examined with immunohistochemistry and real-time PCR. The results revealed that the mRNA levels of ESR1, VEGFA, and Integrin αV and β3 were significantly increased in the high-dose FA group and significantly decreased in the folate deficiency group compared to the control group (p < 0.05). Based on these results, it can be concluded that FA supplementation before pregnancy has positive effects on the maintenance of pregnancy, and folate deficiency may lead to implantation disorders.

Transcriptome profiling reveals dysregulation of inflammatory and protein synthesis genes in PCOS

To analyze the differential expression genes of polycystic ovary syndrome (PCOS), clarify their functions and pathways, as well as the protein-protein interaction network, identify HUB genes, and explore the pathological mechanism. PCOS microarray datasets were screened from the GEO database. Common differentially expressed genes (co-DEGs) were obtained using GEO2R and Venn analysis. Enrichment and pathway analyses were conducted using the DAVID online tool, with results presented in bubble charts. Protein-protein interaction analysis was performed using the STRING tool. HUB genes were identified using Cytoscape software and further interpreted with the assistance of the GeneCards database. A total of two sets of co-DEGs (108 and 102), key proteins (15 and 55), and hub genes (10 and 10) were obtained. The co-DEGs: (1) regulated inflammatory responses and extracellular matrix, TNF, and IL-17 signaling pathways; (2) regulated ribosomes and protein translation, ribosome and immune pathways. The key proteins: (1) regulated inflammation, immunity, transcription, matrix metabolism, proliferation/differentiation, energy, and repair; (2) regulated ubiquitination, enzymes, companion proteins, respiratory chain components, and fusion proteins. The Hub genes: (1) encoded transcription factors and cytokines, playing vital roles in development and proliferation; (2) encoded ribosomes and protein synthesis, influencing hormone and protein synthesis, associated with development and infertility. The dysregulated expression of inflammation and protein synthesis genes in PCOS may be the key mechanism underlying its onset and progression.

Activated eosinophils in early life impair lung development and promote long-term lung damage

Exaggeration of type 2 immune responses promotes lung inflammation and altered lung development; however, eosinophils, despite expansion in the postnatal lung, have not been specifically assessed in the context of neonatal lung disease. Furthermore, early life factors including prematurity and respiratory infection predispose infants to chronic obstructive pulmonary disease later in life. To assess eosinophils in the developing lung and how they may contribute to chronic lung disease, we generated mice harboring eosinophil-specific deletion of the negative regulatory enzyme SH2 domain-containing inositol 5' phosphatase-1. This increased the activity and number of pulmonary eosinophils in the developing lung, which was associated with impaired lung development, expansion of activated alveolar macrophages (AMφ), multinucleated giant cell formation, enlargement of airspaces, and fibrosis. Despite regression of eosinophils following completion of lung development, AMφ-dominated inflammation persisted, alongside lung damage. Bone marrow chimera studies showed that SH2 domain-containing inositol 5' phosphatase-1-deficient eosinophils were not sufficient to drive inflammatory lung disease in adult steady-state mice but once inflammation and damage were present, it could not be resolved. Depletion of eosinophils during alveolarization alleviated pulmonary inflammation and lung pathology, demonstrating an eosinophil-intrinsic effect. These results show that the presence of activated eosinophils during alveolarization aggravates AMφs and promotes sustained inflammation and long-lasting lung pathology.

Impaired fertility in adenomyosis: a murine model reveals endometrial receptivity and progesterone resistance imbalances

In brief

The impact of adenomyosis on reproductive health needs to be fully understood. By using a murine model, this study provides novel insights into the nuanced mechanisms associated with fertility challenges and offers a foundation for targeted interventions.

Abstract

This study investigates the intricate relationship between adenomyosis and reproductive health using a murine model, offering novel insights into this prevalent gynecological disorder. Adenomyosis, characterized by the invasive growth of endometrial tissue into the myometrium, is believed to negatively impact fertility. However, the challenge lies in disentangling this influence, as adenomyosis often coexists with other gynecological diseases. A tamoxifen-induced mice model presents a significant advantage by enabling the specific study of adenomyosis, devoid of confounding influences of concurrent gynecological diseases such as endometriosis. Focusing exclusively on adenomyosis, our study aims to elucidate pathogenic mechanisms underlying fertility issues, focusing on estrous cyclicity, ovarian follicle development, and overall fertility. Our findings uncover disruptions in estrous cyclicity, characterized by an increased duration of time spent in the estrus phase in adenomyosis-induced mice. These disturbances are potentially linked to observed compromised folliculogenesis and the remarkable reduction in litter number and size in mice affected by adenomyosis. Moreover, this study unveils potential drivers of subfertility such as progesterone resistance and altered endometrial receptivity. Within the uteri of mice with adenomyosis, reduced expression of the progesterone receptor and a decreased expression of two implantation-related markers (HoxA10 and integrin β3) were observed. This comprehensive examination sheds light on the nuanced complexities of adenomyosis-associated reproductive challenges, providing a foundation for targeted interventions in addressing fertility issues related to this disease.

Ghrelin misbalance affects mice embryo implantation and pregnancy success by uterine immune dysregulation and nitrosative stress

Introduction

In a previous study we found that ghrelin (Ghrl) misbalance during the peri-implantation period significantly impaired fetus development. In this study we aimed to evaluate the putative mechanisms underlying these effects, including embryo implantation success, uterine nitric oxide synthase (NOS) activity, nitric oxide synthesis and the inflammatory/immune uterine profile.

Methods

Ghrelin misbalance was induced by injecting 4nmol/animal/day of Ghrl (hyperghrelinemia) or 6nmol/animal/day of a Ghrl antagonist (Ant: (D-Lys3)GHRP-6) from day 3 to 8 of pregnancy. Control animals (C) were injected with de vehicle. Females were euthanized at pregnancy day 8 and their uteri excised in order to evaluate: the percentage of reabsorbed embryos (microscopically), eNOS, iNOS and nytrotirosine expression (by immunohistochemistry), nitrite synthesis (by Griess technique), VEGF, IL-10, IL-17, IL-6, MMP9 and GM-CSF expression (by qPCR) and leukocyte infiltration by flow cytometry (evaluating T cells, NK cells, granulocytes, dendritic cells and macrophages).

Results

Ant-treatment significantly increased the percentage of reabsorbed embryos and the uterine expression of eNOS, iNOS and nytrotirosine. (D-Lys3)GHRP-6-treatment increased also the expression of the inflammatory cytokines IL-6, IL-17 and MMP9, and decreased that of IL-10 (anti-inflammatory). Moreover, Ant-treatment increased also the NK cells population and that of CD11b+ dendritic cells; and decreased T cells percentages. Similarly, hyperghrelinemia showed a significant increase vs. C on eNOS, iNOS and nytrotirosineuterine expression and a decrease in T cells percentages.

Conclusion

Ghrl misbalance during the peri-implantation period induces pro-inflammatory changes and nitrosative stress in the gravid uterus, impairing significantly embryo implantation and/or development.

Development of severe colitis is associated with lung inflammation and pathology

Inflammatory bowel diseases (IBD) such as Crohn’s disease and ulcerative colitis are chronic relapsing diseases that affect the gastrointestinal tract, most commonly the colon. A link between the gut and the lung is suggested since patients with IBD have an increased susceptibility for chronic inflammatory lung disease. Furthermore, in the absence of overt lung disease, IBD patients have worsened lung function and more leukocytes in sputum than healthy individuals, highlighting a conduit between the gut and lung in disease. To study the gut-lung axis in the context of IBD, we used TCRδ-/- mice, which are highly susceptible to dextran sulfate sodium (DSS) due to the importance of γδ T cells in maintenance of barrier integrity. After induction of experimental colitis using DSS, the lungs of TCRδ-/- mice exhibited signs of inflammation and mild emphysema, which was not observed in DSS-treated C57BL/6 mice. Damage to the lung tissue was accompanied by a large expansion of neutrophils in the lung parenchyma and an increase in alveolar macrophages in the lung wash. Gene expression analyses showed a significant increase in Csf3, Cxcl2, Tnfa, and Il17a in lung tissue in keeping with neutrophil infiltration. Expression of genes encoding reactive oxygen species enzymes and elastolytic enzymes were enhanced in the lungs of both C57BL/6 and TCRδ-/- mice with colitis. Similarly, surfactant gene expression was also enhanced, which may represent a protective mechanism. These data demonstrate that severe colitis in a susceptible genetic background is sufficient to induce lung inflammation and tissue damage, providing the research community with an important tool for the development of novel therapeutics aimed at reducing co-morbidities in IBD patients.

Identification of differentially expressed genes associated with precocious puberty by suppression subtractive hybridization in goat pituitary tissues

The aim of this study was to identify genes related to precocious puberty expressed in the pituitary of goats at different growth stages by suppression subtractive hybridization (SSH). The pituitary glands from Jining Gray (JG) goats (early puberty) and Liaoning Cashmere (LC) goats (late puberty) at 30, 90, and 180 days were used in this study. To identify differentially expressed genes (DEGs) in the pituitary glands, mRNA was extracted from these tissues, and SSH libraries were constructed and divided into the following groups: juvenile group (30-JG vs. 30-LC, API), puberty group (90-JG vs. 180-LC, BPI), and control group (90-JG vs. 90-LC, EPI). A total of 60, 49, and 58 DEGs were annotated by 222 Gene Ontology (GO) terms and 75 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Most of the DEGs were significantly enriched in GO terms related to 'structural constituent of ribosome', 'translation' and 'GTP binding', and numerous DEGs were also significantly enriched in KEGG terms related to the Jak-STAT signaling and oocyte meiosis pathways. Candidate genes associated with precocious puberty and sexual development were screened from the SSH libraries. These genes were analyzed to determine if they were expressed in the pituitary tissues of the goats at different growth stages and to identify genes that may influence the hypothalamic-pituitary-gonadal (HPG) axis. In this study, we found precocious puberty-related genes (such as PRLP0, EIF5A, and YWHAH) that may be interesting from an evolutionary perspective and that could be investigated for use in future goat breeding programs. Our results provide a valuable dataset that will facilitate further research into the reproductive biology of goats.

Granulocyte colony-stimulating factor is not pathogenic in lupus nephritis

Systemic lupus erythematosus (lupus) is an autoimmune disease characterized by autoantibodies that form immune complexes with self‐antigens, which deposit in various tissues, leading to inflammation and disease. The etiology of disease is complex and still not completely elucidated. Dysregulated inflammation is an important disease feature, and the mainstay of lupus treatment still utilizes nonspecific anti‐inflammatory drugs. Granulocyte colony‐stimulating factor (G‐CSF) is a growth, survival, and activation factor for neutrophils and a mobilizer of hematopoietic stem cells, both of which underlie inflammatory responses in lupus. To determine whether G‐CSF has a causal role in lupus, we genetically deleted G‐CSF from Lyn‐deficient mice, an experimental model of lupus nephritis. Lyn^−/−G‐CSF^−/− mice displayed many of the inflammatory features of Lyn‐deficient mice; however, they had reduced bone marrow and tissue neutrophils, consistent with G‐CSF's role in neutrophil development. Unexpectedly, in comparison to aged Lyn‐deficient mice, matched Lyn^−/−G‐CSF^−/− mice maintained neutrophil hyperactivation and exhibited exacerbated numbers of effector memory T cells, augmented autoantibody titers, and worsened lupus nephritis. In humans, serum G‐CSF levels were not elevated in patients with lupus or with active renal disease. Thus, these studies suggest that G‐CSF is not pathogenic in lupus, and therefore G‐CSF blockade is an unsuitable therapeutic avenue.

Improved diabetic wound healing by LFcinB is associated with relevant changes in the skin immune response and microbiota

Bovine lactoferricin (LFcinB) has antimicrobial and immunomodulatory properties; however, the effects on diabetic wound healing remain poorly understood. The wound healing potential of LFcinB was investigated with in vitro, ex vivo, and in vivo models. Cell migration and proliferation were tested on keratinocytes and on porcine ears. A type 1 diabetic mouse model was also used to evaluate wound healing kinetics, bacterial diversity patterns, and the effect of LFcinB on oxidative stress, macrophage phenotype, angiogenesis, and collagen deposition. LFcinB increased keratinocyte migration in vitro (p < 0.05) and ex vivo (p < 0.001) and improved wound healing in diabetic mice (p < 0.05), though not in normoglycemic control mice. In diabetic mouse wounds, LFcinB treatment led to the eradication of Bacillus pumilus, a decrease in Staphylococcus aureus, and an increase in the Staphylococcus xylosus prevalence. LFcinB increased angiogenesis in diabetic mice (p < 0.01), but this was decreased in control mice (p < 0.05). LFcinB improved collagen deposition in both diabetic and control mice (p < 0.05). Both oxidative stress and the M1-to-M2 macrophage ratios were decreased in LFcinB-treated wounds of diabetic animals (p < 0.001 and p < 0.05, respectively) compared with saline, suggesting a downregulation of inflammation in diabetic wounds. In conclusion, LFcinB treatment demonstrated noticeable positive effects on diabetic wound healing.

Testosterone Reduces Tight Junction Complexity and Down-regulates Expression of Claudin-4 and Occludin in the Endometrium in Ovariectomized, Sex-steroid Replacement Rats

BACKGROUND/AIM

It was hypothesized that endometrial tight junction morphology and expression of tight junction proteins i.e., claudin-4 and occludin in the uterus, are affected by testosterone. Therefore, the effects of testosterone on these parameters in the uterus during receptivity period were investigated.

MATERIALS AND METHODS

Ovariectomized adult female rats were given testosterone (1 mg/kg/day) alone or in combination with flutamide or finasteride between days 6 to 8 of sex-steroid replacement treatment, which was considered the period of uterine receptivity. Ultramorphology of tight junctions was visualized by transmission electron microscopy while distribution and expression of claudin-4 and occludin were examined by immunofluorescence and real-time polymerase chain reaction respectively.

RESULTS

Administration of testosterone caused loss of tight junction complexity and down-regulated expression of claudin-4 and occludin in the uterus.

CONCLUSION

Decreased endometrial tight junction complexity and expression of claudin-4 and occludin in the uterus during receptivity period by testosterone may interfere with embryo attachment and subsequent implantation.

Zearalenone Induces Endoplasmic Reticulum Stress and Modulates the Expression of Phase I/II Enzymes in Human Liver Cells

Zearalenone (ZEN) is a mycotoxin produced by Fusarium species; however, its mechanisms of action in human livers have not been fully elucidated. Thus, we investigated the toxic mechanisms of ZEN in human liver cells. HepG2 cells were treated with ZEN (0-40 μg/mL) for up to 24 h. A significant decrease in cell viability was observed after treatment with 20 and 40 μg/mL of ZEN, including a significant increase in apoptosis and reactive oxygen species production. ZEN increased GRP78 and CHOP, and eIF2α phosphorylation, indicating ER stress; elevated transcription of the autophagy-associated genes, beclin1 and LC3, and translation of LC3; and increased phase I metabolism by increasing PXR and CYP3A4. The protein expression level of CYP3A4 was higher with ZEN treatment up to 20 μg/mL, but remained at the control level after treatment with 40 μg/mL ZEN. In phase II metabolism, Nrf2 activation and UGT1A expression were increased with ZEN treatment up to 20 μg/mL. Treating cells with an ER stress inhibitor alleviated ZEN-induced cell death and autophagy, and inhibited the expression of phase I/II enzymes. Overall, high ZEN concentrations can modulate the expression of phase I/II enzymes via ER stress and reduced protein levels in human liver cells.

Validation of Reference Genes for Gene Expression Normalization in RAW264.7 Cells under Different Conditions

RAW264.7 is a macrophage strain derived from mice tumour and shows a significant ability in antigen uptake. Real-time quantitative PCR (RT-qPCR) is one of the most commonly used methods in gene studies and requires suitable reference genes to normalize and quantitate the expression of gene of interest with sensitivity and specificity. However, suitable reference genes in RAW264.7 cells have not yet been identified for accurate gene expression quantification. In the current study, we evaluated expression levels of ten candidate reference genes in RAW264.7 cells under different conditions. RT-qPCR results indicated significant differences in the expression levels among the ten reference genes. Statistical analyses were carried out using geNorm, NormFinder, and BestKeeper software to further investigate the stability of the reference genes. Integrating the results from the three analytical methods, cytochrome c-1 and hydroxymethylbilane synthase were found to be the most stable and therefore more suitable reference genes, while ribosomal protein L4 and cyclophilin A were the least stable. This study emphasises the importance of identifying and selecting the most stable reference genes for normalization and provides a basis for future gene expression studies using RAW264.7 cells.

Construction of industrial baker's yeast with high level of cAMP

Cyclic adenosine monophosphate (cAMP) plays an important role in modulating the activity of microbe cell. In this study, PKA (protein kinase A) activity was weakened through truncation of TPK2 promoter (-150 bp and -300 bp) and gene deletion of BCY1 (encodes the regulatory subunit of PKA), TPK1 and TPK3, generating strains BY9a-T2-150 and BY9a-T2-300, respectively. High-performance liquid chromatography analysis showed cAMP levels in BY9a-T2-150 and BY9a-T2-300 were increased by 5- and 18-fold, respectively, compared with that of parent strain, BY9a. The expression levels of TPK2 gene in two engineered strains were decreased by 95% and 97% compared with that of BY9a, respectively. The PKA activity reflected by heat resistance of engineered strains enhanced compared with parent strain BY9a. This study show a new method to increase the intracellular cAMP concentration in industrial yeast by fine-tuning of PKA activity, without influence in growth and fermentation properties. PRACTICAL APPLICATIONS: cAMP as the "second messenger," is essential for plant, animal, and microorganisms and human life. But its synthesis is still limited by expensive cost and time-consuming method. We constructed the industrial baker's yeast with high level of cAMP and desired to be used to produce functional food for relaxing smooth muscle, expanding blood vessels, improving liver function, and promoting nerve regeneration and as a food additive for treating hyperthyreosis and hepatopathy. The methods of two step homologous recombination and backcross operated in this study eliminate the exogenous gene in engineered strains, made it safety to be used in food production. Fine-tuning of PKA activity in engineered strains ensure produce high level of cAMP and exhibit normal growth performance in engineering strains. Therefore, this work is significant in functional foods product and has the potential to be used in practical application.

Alternation of ten-eleven translocation 1, 2, and 3 expression in eutopic endometrium of women with endometriosis-associated infertility

Little is known about the differences in ten-eleven translocation 1, 2, and 3 (TET1-3) expression in the endometrial phases in eutopic endometrium from infertile women with endometriosis (IWE) and fertile women without endometriosis (FW). Using RT-qPCR and western blot analysis, we assessed the TET expression in the mid-follicular and mid-luteal phases in eutopic endometrium from IWE (n = 38) and FW (n = 18). Both IWE and FW underwent laparoscopic and histological examinations for endometriosis. In the mid-luteal eutopic endometrium in IWE, compared to that of FW, we found significantly reduced levels of TET1 transcripts and proteins (p = .001 and p = .003, respectively) at the severity stage of I/II (p = .029 and p = .003, respectively) and transcripts only at the severity stage of III/IV (p = .003). In the mid-follicular eutopic endometrium of IWE, compared to that of FW, there was a statistically significant reduction in TET2 transcript levels at the severity stage of III/IV (p = .037). Compared to the mid-follicular endometrium, we found a statistically significant increase in TET3 transcript levels during the mid-luteal phase in the eutopic endometrium of all IWE (p = .034) and in the severity stage of III/IV (p = .025). We observed a change in the expression levels of TET1-3 in the eutopic endometrium of IWE.

Selection of reference genes for expression analysis in mouse models of acute alcoholic liver injury

Investigations of hepatic gene expression are crucial for determining the molecular factors involved in acute alcoholic liver injury. The results of liver molecular investigations may reveal etiologically important genomic alterations. Therefore, it is necessary to normalize gene expression data to identify stable genes, which may be used as a reference under different experimental conditions. The aim of the present study was to apply reverse transcription‑quantitative polymerase chain reaction analysis and use analysis software to investigate the expression stability of candidate reference genes in hepatic tissues from mice with acute alcoholic liver injury. The acute alcoholic liver injury models were established by the intragastric administration of alcohol (5 mg/kg) in Imprinting Control Region mice. Total RNA was isolated from the mouse livers, following which the expression levels of seven reference genes, β-actin, glyceraldehyde 3-phosphate dehydrogenase (Gadph), glucuronidase β, hypoxanthine phosphoribosyltransferase 1 (Hprt1), 18S ribosomal RNA, TATA binding protein and β‑2 microglobulin, were examined, and gene expression stability was assessed using the geNorm, NormFinder and BestKeeper tools. The geNorm analysis revealed that the gene with the lowest variability was Hprt1. Hprt1 and Gapdh were validated as the optimal reference gene pair in all samples from all groups. The NormFinder and BestKeeper results showed that Hprt1 was the most stable gene in all samples. Alcohol induces endoplasmic reticulum (ER) stress, causing changes in the expression levels of ER stress‑associated genes. The stability of Hprt1 was verified by the expression analysis of ER stress‑associated genes, and gene expression levels in the ethanol groups were upregulated, with a significant difference in expression, compared with those in the control group. Therefore, Hprt1 was selected as the most stable gene, and Hprt1 and Gapdh were determined to be the optimum gene pair in mouse models of acute alcoholic liver injury. The reliability of the Hprt1 gene was confirmed by expression analysis of ER stress‑associated genes.

Reference Gene Selection for Quantitative Real-Time Reverse-Transcriptase PCR in Annual Ryegrass (Lolium multiflorum) Subjected to Various Abiotic Stresses

To select the most stable reference genes in annual ryegrass (Lolium multiflorum), we studied annual ryegrass leaf tissues exposed to various abiotic stresses by qRT-PCR and selected 11 candidate reference genes, i.e., 18S rRNA, E2, GAPDH, eIF4A, HIS3, SAMDC, TBP-1, Unigene71, Unigene77, Unigene755, and Unigene14912. We then used GeNorm, NormFinder, and BestKeeper to analyze the expression stability of these 11 genes, and used RefFinder to comprehensively rank genes according to stability. Under different stress conditions, the most suitable reference genes for studies of leaf tissues of annual ryegrass were different. The expression of the eIF4A gene was the most stable under drought stress. Under saline-alkali stress, Unigene14912 has the highest expression stability. Under acidic aluminum stress, SAMDC expression stability was highest. Under heavy metal stress, Unigene71 expression had the highest stability. According to the software analyses, Unigene14912, HIS3, and eIF4A were the most suitable for analyses of abiotic stress in tissues of annual ryegrass. GAPDH was the least suitable reference gene. In conclusion, selecting appropriate reference genes under abiotic stress not only improves the accuracy of annual ryegrass gene expression analyses, but also provides a theoretical reference for the development of reference genes in plants of the genus Lolium.

Combinatorial effects of quercetin and sex-steroids on fluid and electrolytes' (Na+, Cl-, HCO3-) secretory mechanisms in the uterus of ovariectomised female Sprague-Dawley rats

Dysregulation of uterine fluid environment could impair successful reproduction and this could be due to the effect of environmental estrogens. Therefore, in this study, effect of quercetin, an environmental estrogen on uterine fluid and electrolytes concentrations were investigated under sex-steroid influence. Ovariectomised adult female Sprague-Dawley rats were given 10, 50 or 100mg/kg/day quercetin subcutaneously with 17-β estradiol (E) for seven days or three days E, then three days E plus progesterone (P) (E+P) treatment. Uterine fluid secretion rate, Na⁺, Cl^- and HCO₃^- concentrations were determined by in-vivo perfusion. Following sacrifice, uteri were harvested and levels of the proteins of interest were identified by Western blotting and Realtime PCR. Distribution of these proteins in the uterus was observed by immunofluorescence. Levels of uterine cAMP were measured by enzyme-linked immunoassay (EIA). Administration of quercetin at increasing doses increased uterine fluid secretion rate, Na⁺, Cl^- and HCO₃^- concentrations, but to the levels lesser than that of E. In concordant, levels of CFTR, SLC4A4, ENaC (α, β and γ), Na⁺/K⁺-ATPase, GPα/β, AC and cAMP in the uterus increased following increased in the doses of quercetin. Co-administration of quercetin with E caused uterine fluid secretion rate, Na⁺, Cl^- and HCO₃^- concentrations to decrease. In concordant, uterine CFTR, SLC26A6, SLC4A4, ENaC (α, β and γ), Na⁺/K⁺-ATPase, GPα/β, AC and cAMP decreased. Greatest effects were observed following co-administration of 10mg/kg/day quercetin with E. Co-administration of quercetin with E+P caused uterine fluid Na⁺ and HCO₃^- concentrations to increase but no changes in fluid secretion rate and Cl^- concentration were observed. Co-administration of high dose quercetin (100 mg/kg/day) with E+P caused uterine CFTR, SLC26A6, AC, GPα/β and ENaC (α, β and γ) to increase. Quercetin-induced changes in the uterine fluid secretion rate and electrolytes concentrations could potentially affect the uterine reproductive functions under female sex-steroid influence.

Combinatorial effect of genistein and female sex-steroids on uterine fluid volume and secretion rate and aquaporin (AQP)-1, 2, 5, and 7 expression in the uterus in rats

We hypothesized that genistein can interfere with the regulation of uterine fluid volume, secretion rate and expression of aquaporin in the uterus by female sex-steroids, i.e., estrogen and progesterone. Therefore, the aims of this study were to investigate changes in these parameters in the presence of genistein and female sex-steroids.

METHODS

Female Sprague-Dawley rats were ovariectomized and received 3-days estradiol-17β benzoate (E2) plus genistein (25, 50, or 100 mg kg^-1  day^-1 ) or 3-days E2 followed by 3-days E2 plus progesterone with genistein (25, 50, or 100 mg kg^-1  day^-1 ). A day after last treatment, uterine fluid secretion rate was determined by in vivo uterine perfusion with rats under anesthesia. Animals were sacrificed and uteri were harvested and subjected for histological analyses. Luminal/outer uterine circumference was determined and distribution of AQP-1, 2, 5, and 7 in endometrium was visualized by immunofluorescence. Expression of AQP-1, 2, 5, and 7 proteins and mRNAs were determined by Western blotting and Real-time PCR respectively.

RESULTS

Combined treatment of E2 with high dose genistein (50 and 100 mg kg^-1  day^-1 ) resulted in significant decrease in uterine fluid volume, secretion rate and expression of AQP-1, 2, 5, and 7 proteins and mRNAs in uterus (p < 0.05). No significant changes in these parameters were observed when 25 mg kg^-1  day^-1 genistein was given with E2 or when genistein was given with E2 followed by E2 plus progesterone Conclusions: Decreased in uterine fluid volume, secretion rate and AQP-1, 2, 5, and 7 expression in the uterus by high dose genistein in the presence of E2 could potentially affect female fertility. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 832-844, 2017.

Estradiol, progesterone and genistein differentially regulate levels of aquaporin (AQP)-1, 2, 5 and 7 expression in the uteri of ovariectomized, sex-steroid deficient rats

In this study, effects of estradiol, progesterone and genistein on uterine aquaporin (AQP)-1, 2, 5 and 7 expression were investigated in sex-steroid deficient state which could help to elucidate the mechanisms underlying uterine fluid volume changes that were reported under these hormone and hormone-like compound influences.

METHODS

Uteri from ovariectomized, female Sprague-Dawley rats receiving seven days estradiol, progesterone or genistein (25, 50 and 100mg/kg/day) were harvested and levels of AQP-1, 2, 5 and 7 proteins and mRNAs were determined by Western blotting and Real-time PCR (qPCR) respectively. Distribution of these proteins in uterus was observed by immunohistochemistry.

RESULTS

Genistein caused a dose-dependent increase in uterine AQP-1, 2, 5 and 7 protein and mRNA expression, however at the levels lower than following estradiol or progesterone stimulations. Effects of genistein were antagonized by estradiol receptor blocker, ICI 182780. Estradiol caused the highest AQP-2 protein and mRNA expression while progesterone caused the highest AQP-1, 5 and 7 protein and mRNA expression in uterus. AQP-1, 2, 5 and 7 protein were found to be distributed in the myometrium as well as in uterine luminal and glandular epithelia and endometrial blood vessels. In conclusion, the observed effects of estradiol, progesterone and genistein on uterine AQP-1, 2, 5 and 7 expression could help to explain the differences in the amount of fluid accumulated in the uterus under these different conditions.

The 60S ribosomal protein L13 is the most preferable reference gene to investigate gene expression in selected organs from turkeys and chickens, in context of different infection models

Evaluation of reference genes for expression studies in chickens and turkeys is very much limited and unavailable for various infectious models. In this study, eight candidate reference genes HMBS, HPRT1, TBP, VIM, TFRC, RPLP0, RPL13 and RPS7 were evaluated by five different algorithms (GeNorm, NormFinder, BestKeeper©, delta CT, RefFinder) to assess their stability. In order to analyze a broad variation of tissues, spleen, liver, caecum and caecal tonsil of different aged specific pathogen free (SPF) layer chickens and commercial turkeys, uninfected or infected with the extracellular pathogen Histomonas meleagridis, were included. For tissue samples from SPF chickens RPL13 and TBP were found to be the most stable reference genes. Further testing of RPL13 and TBP in the same organs of uninfected and infected SPF broiler chickens with the intracellular pathogen fowl aviadenovirus confirmed this finding. In tissue samples from turkeys, a stable expression of RPL13 and TFRC genes was noticed. Overall, the determined reference genes should be considered whenever gene expression studies in spleen, liver, caecum and caecal tonsil of chickens and turkeys are performed.

An immortalized steroidogenic goat granulosa cell line as a model system to study the effect of the endoplasmic reticulum (ER)-stress response on steroidogenesis

With granulosa and theca cells, the ovaries are responsible for producing oocytes and secreting sex steroids such as estrogen and progesterone. Endoplasmic reticulum stress (ERS) plays an important role in follicle atresia and embryo implantation. In this study, goat granulosa cells were isolated from medium-sized (4-6 mm) healthy follicles. Primary granulosa cells were immortalized by transfection with human telomerase reverse transcriptase (hTERT) to establish a goat granulosa cell line (hTERT-GGCs). These hTERT-GGCs expressed hTERT and had relatively long telomeres at passage 50. Furthermore, hTERT-GGCs expressed the gonadotropin receptor genes CYP11A1, StAR, and CYP19A1, which are involved in steroidogenesis. Additionally, progesterone was detectable in hTERT-GGCs. Although the proliferation potential of hTERT-GGCs significantly improved, there was no evidence to suggest that the hTERT-GGCs are tumorigenic. In addition, thapsigargin (Tg) treatment led to a significant dose-dependent decrease in progesterone concentration and steroidogenic enzyme expression. In summary, we successfully generated a stable goat granulosa cell line. We found that Tg induced ERS in hTERT-GGCs, which reduced progesterone production and steroidogenic enzyme expression. Future studies may benefit from using this cell line as a model to explore the molecular mechanisms regulating steroidogenesis and apoptosis in goat granulosa cells.

Expression and regulation of ATF6α in the mouse uterus during embryo implantation

BACKGROUND

ATF6α, one of the sensor proteins in the stress signaling pathway of the endoplasmic reticulum, is located in the membrane of the endoplasmic reticulum. To date, the physiological function of ATF6α in the process of embryo implantation has not been reported.

METHODS

In this study, the expression pattern of ATF6α in the mouse uterus during peri-implantation and the estrous cycle was detected by real-time PCR, western blot and immunohistochemistry.

RESULTS

ATF6α mRNA and protein levels were higher in the uterus near the implantation site on day 5 and were intensely expressed in the secondary decidual zone (SDZ) on days 7-8. In the uteri of pseudopregnant mice, ATF6α mRNA and protein levels were lower on day 5 than on other days. The activating blastocyst and artificial decidualization had an obvious effect of increasing the expression of ATF6α. In addition, the expression of ATF6α was affected by progesterone (P₄) and estrogen (E₂) in ovariectomized mice. This finding is further supported by evidence from mice during the estrous cycle.

CONCLUSIONS

Thus, we have concluded that ATF6α may play an important role during embryo implantation and decidualization.

Effects of whole genome duplication on cell size and gene expression in mouse embryonic stem cells

Alterations in ploidy tend to influence cell physiology, which in the long-term, contribute to species adaptation and evolution. Polyploid cells are observed under physiological conditions in the nerve and liver tissues, and in tumorigenic processes. Although tetraploid cells have been studied in mammalian cells, the basic characteristics and alterations caused by whole genome duplication are still poorly understood. The purpose of this study was to acquire basic knowledge about the effect of whole genome duplication on the cell cycle, cell size, and gene expression. Using flow cytometry, we demonstrate that cell cycle subpopulations in mouse tetraploid embryonic stem cells (TESCs) were similar to those in embryonic stem cells (ESCs). We performed smear preparations and flow cytometric analysis to identify cell size alterations. These indicated that the relative cell volume of TESCs was approximately 2.2–2.5 fold that of ESCs. We also investigated the effect of whole genome duplication on the expression of housekeeping and pluripotency marker genes using quantitative real-time PCR with external RNA. We found that the target transcripts were 2.2 times more abundant in TESCs than those in ESCs. This indicated that gene expression and cell volume increased in parallel. Our findings suggest the existence of a homeostatic mechanism controlling the cytoplasmic transcript levels in accordance with genome volume changes caused by whole genome duplication.

Estrogen maintains myometrial tumors in a lymphangioleiomyomatosis model

Lymphangioleiomyomatosis (LAM) is a rare disease in women. Patients with LAM develop metastatic smooth-muscle cell adenomas within the lungs, resulting in reduced pulmonary function. LAM cells contain mutations in tuberous sclerosis genes (TSC1 or TSC2), leading to up-regulation of mTORC1 activity and elevated proliferation. The origin of LAM cells remains unknown; however, inactivation of Tsc2 gene in the mouse uterus resulted in myometrial tumors exhibiting LAM features, and approximately 50% of animals developed metastatic myometrial lung tumors. This suggests that LAM tumors might originate from the uterine myometrium, possibly explaining the overwhelming prevalence of LAM in female. Here, we demonstrate that mouse Tsc2-null myometrial tumors exhibit nearly all the features of LAM, including mTORC1/S6K activation, as well as expression of melanocytic markers and matrix metalloproteinases (MMPs). Estrogen ablation reduces S6K signaling and results in Tsc2-null myometrial tumor regression. Thus, even without TSC2, estradiol is required to maintain tumors and mTORC1/S6K signaling. Additionally, we find that MMP-2 and -9, as well as neutrophil elastase (NE), are overexpressed in Tsc2-null myometrial tumors in an estrogen-dependent fashion. In vivo fluorescent imaging using MMP- or NE-sensitive optical biomarkers confirms that protease activity is specific to myometrial tumors. Similar to LAM cells, uterine Tsc2-null myometrial cells also overexpress melanocytic markers in an estrogen-dependent fashion. Finally, we identify glycoprotein NMB (GPNMB) as a melanocytic marker up-regulated in Tsc2-null mouse uteri and human LAM samples. Our data highlight the potential importance of estradiol in LAM cells, suggesting that anti-estrogen therapy may be a treatment modality. Furthermore, proteases and GPNMB might be useful LAM biomarkers.

Estrogen and progesterone differentially regulate carbonic anhydrase II, III, IX, XII, and XIII in ovariectomized rat uteri

Changes in the uterus expression of carbonic anhydrase (CA) II, III, IX, XII, and XIII were investigated under the influence of sex-steroids in order to elucidate mechanisms underlying differential effects of these hormones on uterine pH. Uteri of ovariectomised rats receiving over three days either vehicle, estrogen, or progesterone or three days estrogen followed by three days either vehicle or progesterone were harvested. Messenger RNA (mRNA) and protein levels were quantified by real-time PCR and Western blotting, respectively. The distribution of CA isoenzymes proteins were examined by immunohistochemistry. The levels of CAII, III, XII, and XIII mRNAs and proteins were elevated while levels of CAIX mRNA and protein were reduced following progesterone-only and estrogen plus progesterone treatment, compared to the control and estrogen plus vehicle, respectively. Following estrogen treatment, expression of CAII, IX, XII, and CAXIII mRNAs and proteins were reduced, but remained at a level higher than control, except for CAIX, where its level was higher than the control and following progesterone treatment. Under progesterone-only and estrogen plus progesterone influences, high levels of CAII, III, XII, and XIII were observed in uterine lumenal and glandular epithelia and myometrium. However, a high level of CAIX was observed only under the influence of estrogen at the similar locations. In conclusion, high expression of CAII, III, XII, and XIII under the influence of progesterone and estrogen plus progesterone could result in the reduction of uterine tissue and fluid pH; however, the significance of high levels of CAIX expression under the influence of estrogen remains unclear.

Genome-wide identification and characterization of reference genes with different transcript abundances for Streptomyces coelicolor

The lack of reliable reference genes (RGs) in the genus Streptomyces hampers effort to obtain the precise data of transcript levels. To address this issue, we aimed to identify reliable RGs in the model organism Streptomyces coelicolor. A pool of potential RGs containing 1,471 genes was first identified by determining the intersection of genes with stable transcript levels from four time-series transcriptome microarray datasets of S. coelicolor M145 cultivated in different conditions. Then, following a strict rational selection scheme including homology analysis, disturbance analysis, function analysis and transcript abundance analysis, 13 candidates were selected from the 1,471 genes. Based on real-time quantitative reverse transcription PCR assays, SCO0710, SCO6185, SCO1544, SCO3183 and SCO4758 were identified as the top five genes with the most stable transcript levels among the 13 candidates. Further analyses showed these five genes also maintained stable transcript levels in different S. coelicolor strains, as well as in Streptomyces avermitilis MA-4680 and Streptomyces clavuligerus NRRL 3585, suggesting they could fulfill the requirements of accurate data normalization in streptomycetes. Moreover, the systematic strategy employed in this work could be used for reference in other microorganism to select reliable RGs.

Combinatorial effects of genistein and sex-steroids on the level of cystic fibrosis transmembrane regulator (CFTR), adenylate cyclase (AC) and cAMP in the cervix of ovariectomised rats

The combinatorial effects of genistein and estrogen (E) or estrogen plus progesterone (E+P) on CFTR, AC and cAMP levels in cervix were investigated. Ovariectomised adult female rats received 50 or 100mg/kg/day genistein with E or E followed by E+P [E+(E+P)] for seven consecutive days. Cervixes were harvested and analyzed for CFTR mRNA levels by Real-time PCR. Distribution of AC and CFTR proteins in endocervix were observed by immunohistochemistry. Levels of cAMP were measured by enzyme-immunoassay. Molecular docking predicted interaction between genistein and AC. Our results indicate that levels of CFTR, AC and cAMP in cervix of rats receiving genistein plus E were higher than E-only treatment (p<0.05) while genistein plus [E+(E+P)] were higher than E+(E+P)-only treatment (p<0.05). In conclusions, increased levels of CFTR, AC and cAMP in cervix of E and E+(E+P)-treated rats by genistein could affect the cervical secretory function which could influence the female reproductive processes.

Vacuolar-ATPase (V-ATPase) Mediates Progesterone-Induced Uterine Fluid Acidification in Rats

We hypothesized that progesterone-induced decrease in uterine fluid pH involves V-ATPase. In this study, expression and functional activity of V-ATPase in uterus were investigated under progesterone influence. Ovariectomized adult female rats received subcutaneous injection of estradiol-17β (1 µg/kg/day) or progesterone (20 mg/kg/day) for 3 days or 3 days estradiol-17β followed by 3 days vehicle, progesterone, or estradiol-17β plus progesterone. Mifepristone, a progesterone receptor blocker, was concomitantly given to the rats which received progesterone. A day after last injection, rate of uterine fluid secretion, its HCO3 (-) concentration, and pH were determined via in vivo uterine perfusion in rats under anesthesia. V-ATPase inhibitor, bafilomycin, was introduced into the perfusion buffer, and changes in these parameters were observed. Expression of V-ATPase A1 and B1/2 proteins and mRNAs in uterus were quantified by Western blotting and real-time PCR, respectively. Distribution of these proteins was observed by immunohistochemistry. Our findings showed that under progesterone influence, uterine fluid secretion rate, HCO3 (-) concentration, and pH were significantly reduced. Administration of bafilomycin did not cause significant changes in fluid secretion rate; however, HCO3 (-) concentration and pH were significantly elevated. In parallel with these changes, expression of V-ATPase A1 and B1/2 proteins and mRNAs were significantly increased with these proteins highly distributed in uterine luminal and glandular epithelia. In conclusion, increased expression and functional activity of V-ATPase were most likely responsible for the decreased in uterine fluid pH observed under progesterone influence.

Genome-wide selection of superior reference genes for expression studies in Ganoderma lucidum

Quantitative real-time polymerase chain reaction (qRT-PCR) is widely used for the accurate analysis of gene expression. However, high homology among gene families might result in unsuitability of reference genes, which leads to the inaccuracy of qRT-PCR analysis. The release of the Ganoderma lucidum genome has triggered numerous studies to be done on the homology among gene families with the purpose of selecting reliable reference genes. Based on the G. lucdum genome and transcriptome database, 38 candidate reference genes including 28 novel genes were systematically selected and evaluated for qRT-PCR normalization. The result indicated that commonly used polyubiquitin (PUB), beta-actin (BAT), and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) were unsuitable reference genes because of the high sequence similarity and low primer specificity. According to the evaluation of RefFinder, cyclophilin 5 (CYP5) was ranked as the most stable reference gene for 27 tested samples under all experimental conditions and eighteen mycelial samples. Based on sequence analysis and expression analysis, our study suggested that gene characteristic, primer specificity of high homologous genes, allele-specificity expression of candidate genes and under-evaluation of reference genes influenced the accuracy and sensitivity of qRT-PCR analysis. This investigation not only revealed potential factors influencing the unsuitability of reference genes but also selected the superior reference genes from more candidate genes and testing samples than those used in the previous study. Furthermore, our study established a model for reference gene analysis by using the genomic sequence.

Quercetin Induces Dose-Dependent Differential Morphological and Proliferative Changes in Rat Uteri in the Presence and in the Absence of Estrogen

Quercetin could have profound effects on uterine morphology and proliferation, which are known to be influenced by estrogen. This study investigated the effect of quercetin on these uterine parameters in the presence and in the absence of estrogen. Ovariectomized adult female rats received peanut oil, quercetin (10, 50, and 100 mg/kg/day), estrogen, or estrogen+quercetin (10, 50, or 100 mg/kg/day) treatment for 7 consecutive days. At the end of the treatment, uteri were harvested for histological and molecular biological analyses. Distribution of proliferative cell nuclear antigen (PCNA) protein in the uterus was observed by immunohistochemistry. Levels of expression of PCNA protein and mRNA in uterine tissue homogenates were determined by Western blotting and real-time polymerase chain reaction, respectively. Our findings indicated that administration of 10 mg/kg/day of quercetin either alone or with estrogen resulted in decreased uterine expression of PCNA protein and mRNA with the percentage of PCNA-positive cells in uterine luminal and glandular epithelia markedly reduced compared with estrogen-only treatment. Changes in uterine morphology were the opposite of changes observed following estrogen treatment. Treatment with 100 mg/kg/day of quercetin either alone or with estrogen resulted in elevated PCNA protein and mRNA expression. In addition, the percentages of PCNA-positive cells in the epithelia, which line the lumen and glands, were increased with morphological features mimicking changes that occur following estrogen treatment. Following 50 mg/kg/day quercetin treatment, the changes observed were in between those changes that occur following 10 and 100 mg/kg/day quercetin treatment. In conclusion, changes in uterine morphology and proliferation following 10 mg/kg/day quercetin treatment could be attributed to quercetin's antiestrogenic properties, while changes that occur following 100 mg/kg/day quercetin treatment could be attributed to quercetin's estrogenic properties.

Enhanced expression of sodium hydrogen exchanger (NHE)-1, 2 and 4 in the uteri of rat model for post-menopause under phytoestrogen genistein influence

Maintaining near normal uterine fluid pH is important for restoring uterine function after menopause. We hypothesized that genistein could restore uterine fluid pH via its effect on NHE expression. This study therefore investigated changes in uterine NHE-1, 2 and 4 expression under genistein influence. Ovariectomized female rats received genistein (25, 50 or 100mg/kg/day) for seven consecutive days. Uteri were harvested and NHE-1, 2 and 4 mRNA expression were analyzed by Real-time PCR while distribution of these transporters' protein was observed by immunohistochemistry. Expression of NHE-1, 2 and 4 mRNA increased with increasing doses of genistein which was antagonized by ICI 182780. Under genistein influence, NHE-1, 2 and 4 proteins were found to be distributed at apical membrane of endometrial luminal epithelia. Enhanced expression of NHE-1, 2 and 4 in ovariectomised rat uteri by genistein might help to restore pH of uterine fluid which could be useful for women after menopause.

Estrogen, progesterone, and genistein differentially regulate levels of expression of α-, β-, and γ-epithelial sodium channel (ENaC) and α-sodium potassium pump (Na⁺/K⁺-ATPase) in the uteri of sex steroid-deficient rats

Estrogen, progesterone, and genistein could induce changes in uterine fluid volume and Na(+) concentration. Progesterone upregulates expression of epithelial sodium channel (ENaC) and Na(+)/K(+)-ATPase which contributed toward these changes. However, effects of estrogen and genistein were unknown. This study therefore investigated changes in expression of these proteins in the uterus under estrogen, progesterone, and genistein influences to further understand mechanisms underlying sex steroids and phytoestrogen effects on uterine fluid Na(+) regulation. In this study, uteri of ovariectomized female rats receiving 7-day treatment with genistein (25, 50, and 100 mg/kg/day), estrogen (0.8 × 10(-4) mg/kg/day), or progesterone (4 mg/kg/day) were harvested, and expression levels of α-, β-, and γ-ENaC proteins and messenger RNAs (mRNAs) and α-Na(+)/K(+)-ATPase protein were determined by Western blotting (proteins) and real-time polymerase chain reaction (mRNA). Meanwhile, distribution of α-, β-, and γ-ENaC and α-Na(+)/K(+)-ATPase proteins in the uterus was identified by immunohistochemistry. Our findings indicated that expression of α-, β-, and γ-ENaC proteins and mRNAs and α-Na(+)/K(+)-ATPase protein were enhanced under progesterone influence. Lower expressions were noted under estrogen and genistein influences compared to progesterone. Under estrogen, progesterone, and genistein influences, α- and β-ENaC were distributed at apical membrane and γ-ENaC was distributed at apical and basolateral membranes of uterine luminal epithelia. Under progesterone influence, α-Na(+)/K(+)-ATPase was highly expressed at basolateral membrane. In conclusion, high expression of α-, β-, and γ-ENaC and α-Na(+)/K(+)-ATPase under progesterone influence would contribute toward increased uterine fluid Na(+) reabsorption, whereas lesser expression of these proteins under estrogen and genistein influences would contribute toward lower reabsorption of uterine fluid Na(+).

Estrogen and progesterone differentially regulate the levels of cystic fibrosis transmembrane regulator (CFTR), adenylate cyclase (AC), and cyclic adenosine mono-phosphate (cAMP) in the rat cervix

The consistency of the cervical mucus changes with the reproductive cycle, which we hypothesized involved changing levels of cystic fibrosis transmembrane regulator (CFTR), adenylate cyclase (AC), and cyclic adenosine mono-phosphate (cAMP). We therefore measured the abundance of each in the rat cervix under estrogen and progesterone influence to determine if the activity of these components could explain the changes in the consistency of cervical mucus. Ovariectomised adult female rats were treated with three days of either estrogen (1 μg/kg/day) or progesterone (20 mg/kg/day), or three days of estrogen followed by two days of either vehicle or progesterone or estrogen plus progesterone. In some groups, mifepristone (7 mg/kg/day) was concurrently given with progesterone. Animals were then sacrificed, and the cervix was harvested for protein and mRNA expression analyses by Western blot and real-time PCR, respectively. The distribution of proteins was investigated by immunohistochemistry, and levels of cAMP were determined by enzyme-linked immunosorbent assay (ELISA). Cftr mRNA, AC protein, and cAMP levels in cervical homogenates as well as the tissue distribution of CFTR and AC in endocervical epithelia were highest under estrogen influence; the opposite pattern was seen under progesterone influence. Cervical lumen circumference was highest under estrogen and lowest under progesterone. The effects of progesterone were antagonized by mifepristone. Therefore, increased abundance of CFTR, AC, and cAMP under estrogen influence could account for the increased fluid accumulation within the cervical lumen, which would contribute to lower cervical mucus consistency, whereas progesterone reverses this effect at the molecular and organ level.

Mycotoxin zearalenone induces apoptosis in mouse Leydig cells via an endoplasmic reticulum stress-dependent signalling pathway

Zearalenone (ZEN) is a Fusarium mycotoxin that causes several reproductive disorders and genotoxic effects. This study demonstrated the involvement of endoplasmic reticulum (ER) stress in ZEN-induced mouse Leydig cell death. Our study showed that ZEN reduced cell proliferation in a murine Leydig tumour cell line in a dose-dependent manner. The involvement of apoptosis as a major cause of ZEN-induced cell death was further confirmed by the results of a caspase-3 activity assay, which showed a ZEN dose-dependent increase in cell death. Treatment of MLTC-1 and primary mouse Leydig cells with ZEN upregulated the expression of the ER stress-typical markers GRP78, CHOP and caspase-12 protein. Further, pre-treating the cells with 4-phenylbutyrate or knocking down GRP78 using lentivirus-encoded shRNA significantly diminished ZEN-induced apoptosis and inhibited the expression of CHOP and caspase-12. In summary, these results suggest that the activation of an ER stress pathway plays a key role in ZEN-induced apoptosis in the mouse Leydig cells.

Enhanced Expression of Sodium Hydrogen Exchanger (NHE)-1, 2 and 4 in the Cervix of Ovariectomised Rats by Phytoestrogen Genistein

Restoring the pH of cervicovaginal fluid is important for the cervicovaginal health after menopause. Genistein, which is a widely consumed dietary health supplement to overcome the post-menopausal complications could help to restore the cervicovaginal fluid pH. We hypothesized that genistien effect involves changes in expression of NHE-1, 2 and 4 proteins and mRNAs in the cervix. This study investigated effect of genistein on NHE-1, 2 and 4 protein and mRNA expression in the cervix in order to elucidate the mechanisms underlying possible effect of this compound on cervicovaginal fluid pH after menopause.

METHODS

Ovariectomised adult female rats received 25, 50 and 100 mg/kg/day genistein for seven consecutive days. At the end of the treatment, animals were sacrificed and cervix was harvested. Expression of Nhe-1, 2 and 4 mRNA were analyzed by Real-time PCR while distribution of NHE-1, 2 and 4 protein were observed by immunohistochemistry.

RESULTS

Treatment with 50 and 100 mg/kg/day genistein caused marked increase in the levels of expression and distribution of NHE-1, 2 and 4 proteins in the endocervical epithelia. Levels of Nhe-1, 2 and 4 mRNA in the cervix were also increased. Coadministration of ICI 182 780 and genistein reduced the expression levels of NHE-1, 2 and 4 proteins and mRNAs in the cervix.

CONCLUSIONS

Enhanced expression of NHE-1, 2 and 4 proteins and mRNAs expression in cervix under genistein influence could help to restore the cervicovaginal fluid pH that might help to prevent cervicovaginal complications related to menopause.

Testosterone decreases fluid and chloride secretions in the uterus of adult female rats via down-regulating cystic fibrosis transmembrane regulator (CFTR) expression and functional activity

OBJECTIVES

Estrogen is known to stimulate uterine fluid and Cl(-) secretion via CFTR. This study investigated testosterone effect on these changes in a rat model.

METHODS

Ovariectomized adult female rats received estrogen for five days or estrogen for three days followed by two days peanut oil or testosterone either alone or in the presence of flutamide or finasteride. At the end of treatment, uteri were perfused with perfusate containing CFTRinh-172. The rate of fluid and Cl(-) secretion were determined. Dose-dependent effect of testosterone and effect of forskolin on fluid secretion rate were measured. Animals were sacrificed and uteri were removed for CFTR protein and mRNA expression analyses, histology and cAMP measurement. Morphology of uterus, levels of expression of CFTR protein and mRNA and distribution of CFTR protein were observed.

RESULTS

Estrogen causes increase while testosterone causes decrease in uterine fluid and Cl(-) secretions. The effects of estrogen but not testosterone were antagonized by CFTRinh-172. Luminal fluid volume and apical expression of CFTR in the luminal epithelia were highest under estrogen and lowest under testosterone influences. Similar changes were observed in CFTR protein and mRNA expressions. Uterine cAMP level was highest under estrogen and lowest under testosterone influence. Forskolin increases fluid secretion rate in estrogen but not in testosterone-treated animals. Testosterone effects were dose-dependent and were antagonized by flutamide however, not finasteride.

CONCLUSIONS

Testosterone inhibition of estrogen-induced uterine fluid and Cl(-) secretion occurs via inhibition of CFTR expression and functional activities. These changes could explain the adverse effects of testosterone on fertility.

Quercetin induces morphological and proliferative changes of rat's uteri under estrogen and progesterone influences

This study investigated the effect of 10 or 100 mg/kg/day quercetin on the uterus of ovariectomized adult female rats receiving sex-steroid replacement regime mimicking changes in hormonal profiles during the reproductive cycle. Following seven days of treatment with estrogen and progesterone with or without quercetin, uteri were harvested for histological and proliferative cell nuclear antigen (PCNA) protein and mRNA expression and PCNA protein distribution analyses. Our findings indicated that co-administration of 10 mg/kg/day quercetin with estrogen and progesterone caused a significant decrease in the size of uterine lumen and epithelial heights with lower PCNA protein and mRNA expression as compared to estrogen plus progesterone-only treatment (P < 0.05). Concomitant treatment with estrogen and progesterone with 100 mg/kg/day quercetin resulted in a marked increase in the number of glands with increased PCNA protein and mRNA expression. Significantly higher PCNA distribution was observed in the stroma and glands as compared to estrogen plus progesterone-only treatment (P < 0.05). In conclusion, at 10 mg/kg/day, quercetin affects uterine morphology but not proliferation, however at 100 mg/kg/day, quercetin induced significant stromal and glandular proliferation which could predispose the uterus towards neoplastic development.

Genistein induces increase in fluid pH, Na+ and HCO3(-) concentration, SLC26A6 and SLC4A4 (NBCe1)-B expression in the uteri of ovariectomized rats

Genistein has been reported to stimulate luminal HCO₃⁻ secretion. We hypothesized that genistein mediates this effect via SLC26A6 and SLC4A4 (NBCe1) transporters. Our study aimed to: investigate changes in uterine fluid pH, Na⁺ and HCO₃⁻ concentration and expression of uterine SLC26A6 and NBCe1 under genistein effect. Ovariectomized adult female rats received 25, 50 and 100 mg/kg/day genistein for a week with and without ICI 182780. A day after the last injection, in vivo uterine perfusion was performed to collect uterine fluid for Na⁺, HCO₃⁻ and pH determination. The animals were then sacrificed and uteri were removed for mRNA and protein expression analyses. SLC26A6 and NBCe1-A and NBCe1-B distribution were visualized by immunohistochemistry (IHC). Genistein at 50 and 100 mg/kg/day stimulates uterine fluid pH, Na⁺ and HCO₃⁻ concentration increase. Genistein at 100 mg/kg/day up-regulates the expression of SLC26A6 and SLC4A4 mRNA, which were reduced following concomitant ICI 182780 administration. In parallel, SLC26A6 and NBCe1-B protein expression were also increased following high dose genistein treatment and were localized mainly at the apical membrane of the luminal epithelia. SLC26A6 and NBCe1-B up-regulation by genistein could be responsible for the observed increase in the uterine fluid pH, Na⁺ and HCO₃⁻ concentration under this condition.

CREBZF expression and hormonal regulation in the mouse uterus

BACKGROUND

CREBZF is a member of the mammalian ATF/CREB family of the basic region-leucine zipper (bZIP) transcription factors. Two isoforms of CREBZF have been identified from the alternative usage of initiation codons, SMILE (long isoform of CREBZF) and Zhangfei (short isoform of CREBZF). Until recently, the physiological function of CREBZF in mammalian reproductions has not been reported.

METHODS

Multiple techniques were performed to investigate the spatiotemporal expression and hormonal regulation of the CREBZF gene in the mouse uterus and its role in embryo implantation.

RESULTS

Zhangfei was not detected in the mouse uterus. SMILE immunostaining was mainly expressed in the uterine luminal and glandular epithelium, and the expression levels of both SMILE mRNA and protein gradually decreased from days 1-3 of pregnancy, peaked on day 4, and then declined again on day 6. On day 5 of pregnancy, SMILE protein expression was detected only in the luminal epithelium at implantation sites compared with the expression at inter-implantation sites. SMILE protein was not detected in decidual cells from days 6-8 of pregnancy or artificial decidualisation. Furthermore, SMILE protein was not detected in the mouse uterus on days 3-6 of pseudopregnancy, and SMILE expression was also induced in the delayed-implantation uterus, indicating that the presence of an active blastocyst was required for SMILE expression at the implantation site. Oestrogen significantly stimulated SMILE expression in the ovariectomised mouse uterus. In addition, in cycling mice, high levels of SMILE protein and mRNA expression were also observed in proestrus and oestrus uteri.

CONCLUSIONS

Taken together, these results suggested that SMILE expression was closely related to mouse implantation and up-regulated by oestrogen.

Modulation of sodium-bicarbonate co-transporter (SLC4A4/NBCe1) protein and mRNA expression in rat's uteri by sex-steroids and at different phases of the oestrous cycle

Oestrogen-induced uterine fluid sodium (Na(+)) and bicarbonate (HCO3(-)) secretion may involve SLC4A4. We hypothesized that uterine SLC4A4 expression changes under different sex-steroid influence, therefore may account for the fluctuation in uterine fluid Na(+) and HCO3(-) content throughout the oestrous cycle. The aim of this study is to investigate the differential effects of sex-steroids and oestrous cycle phases on uterine SLC4A4 expression.

METHODS

Adult female WKY rats were ovariectomised and treated with different doses of 17β-oestradiol (E2) (0.2, 2, 20 and 50 μg/ml/day) or progesterone (P4) (4 mg/ml/day) for three consecutive days and 3 days treatment with 0.2 μg/ml/day E2 followed by another 3 days with P4 to mimic the hormonal changes in early pregnancy. Oestrous cycle phases in intact, non-ovariectomised rats were determined by vaginal smear. The animals were then sacrificed and uteri were removed for protein and mRNA expression analyses by Western blotting and Real Time PCR, respectively. SLC4A4 distribution was observed by immunohistochemistry.

RESULTS

Treatment with increasing E2 doses resulted in a dose-dependent increase in SLC4A4 protein expression. High SLC4A4 protein and mRNA expression can be seen at estrus. SLC4A4 is distributed mainly at the apical as well as basolateral membranes of the luminal and glandular epithelia following E2 treatment and at Es. Meanwhile, SLC4A4 expression was reduced following P4 treatment and was low at diestrus.

CONCLUSION

High SLC4A4 expression under estrogen dominance may contribute to the increase in uterine fluid Na(+) and HCO3(-) content, while its low expression under P4 dominance may result in vice versa.