Isolation and characterization of FMRFamide-like peptides in the venoms of solitary sphecid wasps

Purification of small peptide components in the venoms of the solitary sphecid wasps, Sphex argentatus argentatus and Isodontia harmandi, led to the isolation of several major peptides. Analysis of MS/MS spectra by MALDI-TOF/TOF revealed the sequence of a new peptide Sa112 (EDVDHVFLRF-NH₂), which is structurally very similar to leucomyosupressin (pQDVDHVFLRF-NH₂) and SchistoFLRFamide (PDVDHVFLRF-NH₂), the FMRFamide-like peptides from cockroach and locust, respectively. Indeed, this new peptide, like SchistoFLRFamide, inhibited the frequency and amplitude of spontaneous contractions of the locust oviduct in a dose-dependent manner. A non-amidated peptide Sa12b (EDVDHVFLRF) was also isolated, but this peptide had no effect on spontaneous locust oviduct contraction. This is the first example of a FMRF-like peptide to be found in solitary wasp venom. Additionally, a truncated form of the myosuppressins, which has previously been synthesized and tested for biological activity, DVDHVFLRF-NH₂ (Sh5b), was found for the first time as a natural product. Four other novel peptides were isolated and characterized as Sa81 (EDDLEDFNPTVS), Sa10 (EDDLEDFNPTIA), Sh41 (DDLSDFNPKV), and Sh42 (EDDLSDFNPKV). They are structurally related to each other, having a high content of acidic amino acids, but no structural similarity to any known peptides. Ion channel associated activities of Sh41 and Sh42 were tested, but did not show any activity for Na⁺, K⁺, Ca²⁺ channels.

Exposure to xenoestrogens alters the expression of key morphoregulatory proteins of oviduct adenogenesis in the broad-snouted caiman (Caiman latirostris)

Endocrine disrupting compounds (EDCs) are contaminants ubiquitously found in the environment, which pose a potential threat to aquatic and wetland ecosystems. Caiman latirostris, a crocodilian species that inhabits South American wetlands, is highly sensitive to EDC exposure. Previously, we reported that early postnatal exposure to EDCs such as Bisphenol A (BPA) and 17β-Estradiol (E₂) alters C. latirostris oviduct differentiation. The aim of this work was to elucidate the molecular mechanisms behind this alteration. To accomplish this, we established the ontogenic changes in histological features and the expression of Wnt-7a, Wnt-5a, β-catenin, FoxA2, desmin, and alpha smooth muscle actin (α-SMA) in the oviduct of C. latirostris. Then, we evaluated the effects of BPA and E₂ exposure on these histological features and protein expressions. Our results showed that during the postnatal differentiation of the oviduct the presence of histological features related to adenogenesis is associated with the levels of expression of FoxA2, β-catenin, Wnt-5a and Wnt-7a. Early postnatal exposure to BPA and E₂ decreased the presence of histological features related to adenogenesis and altered the levels of expression of FoxA2, β-catenin, Wnt-5a and Wnt-7a, as well as the desmin/α-SMA ratio. These findings suggest that altered levels of Wnt-7a, Wnt-5a, β-catenin and FoxA2 could play a role in the BPA and E₂-induced alteration in oviduct differentiation in C. latirostris. Thus, impaired adenogenesis and, probably, impaired reproduction in wildlife naturally exposed to BPA and other estrogenic agonists cannot be completely ruled out.

Cell-type specific analysis of physiological action of estrogen in mouse oviducts

One of the endogenous estrogens, 17β-estradiol (E2 ) is a female steroid hormone secreted from the ovary. It is well established that E2 causes biochemical and histological changes in the uterus. However, it is not completely understood how E2 regulates the oviductal environment in vivo. In this study, we assessed the effect of E2 on each oviductal cell type, using an ovariectomized-hormone-replacement mouse model, single-cell RNA-sequencing (scRNA-seq), in situ hybridization, and cell-type-specific deletion in mice. We found that each cell type in the oviduct responded to E2 distinctively, especially ciliated and secretory epithelial cells. The treatment of exogenous E2 did not drastically alter the transcriptomic profile from that of endogenous E2 produced during estrus. Moreover, we have identified and validated genes of interest in our datasets that may be used as cell- and region-specific markers in the oviduct. Insulin-like growth factor 1 (Igf1) was characterized as an E2 -target gene in the mouse oviduct and was also expressed in human fallopian tubes. Deletion of Igf1 in progesterone receptor (Pgr)-expressing cells resulted in female subfertility, partially due to an embryo developmental defect and embryo retention within the oviduct. In summary, we have shown that oviductal cell types, including epithelial, stromal, and muscle cells, are differentially regulated by E2 and support gene expression changes, such as growth factors that are required for normal embryo development and transport in mouse models. Furthermore, we have identified cell-specific and region-specific gene markers for targeted studies and functional analysis in vivo.

Altering the Microbiome Inhibits Tumorigenesis in a Mouse Model of Oviductal High-Grade Serous Carcinoma

Studies have shown bacteria influence the initiation and progression of cancers arising in sites that harbor rich microbial communities, such as the colon. Little is known about the potential for the microbiome to influence tumorigenesis at sites considered sterile, including the upper female genital tract. The recent identification of distinct bacterial signatures associated with ovarian carcinomas suggests microbiota in the gut, vagina, or elsewhere might contribute to ovarian cancer pathogenesis. Here, we tested whether altering the microbiome affects tumorigenesis in a mouse model of high-grade serous carcinoma (HGSC) based on conditional oviduct-specific inactivation of the Brca1, Trp53, Rb1, and Nf1 tumor suppressor genes. Cohorts of control (n = 20) and antibiotic-treated (n = 23) mice were treated with tamoxifen to induce tumor formation and then monitored for 12 months. The antibiotic cocktail was administered for the first 5 months of the monitoring period in the treatment group. Antibiotic-treated mice had significantly fewer and less advanced tumors than control mice at study endpoint. Antibiotics induced changes in the composition of the intestinal and vaginal microbiota, which were durable in the fecal samples. Clustering analysis showed particular groups of microbiota are associated with the development of HGSC in this model. These findings demonstrate the microbiome influences HGSC pathogenesis in an in vivo model that closely recapitulates the human disease. Because the microbiome can modulate efficacy of cancer chemo- and immunotherapy, our genetically engineered mouse model system may prove useful for testing whether altering the microbiota can improve the heretofore poor response of HGSC to immunotherapies. SIGNIFICANCE: This study provides strong in vivo evidence for a role of the microbiome in ovarian cancer pathogenesis.

Chemical and functional analyses of Rhinella icterica (Spix, 1824) toad secretion screened on contractions of the heart and oviduct in Locusta migratoria

Rhinella icterica is a Brazilian toad with a parotoid secretion that is toxic to insects. In this work, we examined the entomotoxicity of this secretion in locust (Locusta migratoria) semi-isolated heart and oviduct preparations in vitro. The parotoid secretion caused negative chronotropism in semi-isolated heart preparations (at the highest dose tested: 500 μg) and markedly enhanced the amplitude of spontaneous contractions and tonus of oviduct muscle (0.001-100 μg). In addition, the secretion enhanced neurally-evoked contractions of oviduct muscle, which was more sensitive to low concentrations of secretion than the semi-isolated heart. The highest dose of secretion (100 μg) caused neuromuscular blockade. In zero calcium-high magnesium saline, the secretion still enhanced muscle tonus, suggesting the release of intracellular calcium to stimulate contraction. Reverse-phase HPLC of the secretion yielded eight fractions, of which only fractions 4 and 5 affected oviduct muscle tonus and neurally-evoked contractions. No phospholipase A₂ activity was detected in the secretion or its chromatographic fractions. The analysis of fractions 4 and 5 by LC-DAD-MS/MS revealed the following chemical compounds: suberoyl arginine, hellebrigenin, hellebrigenin 3-suberoyl arginine ester, marinobufagin 3-pimeloyl arginine ester, telocinobufagin 3-suberoyl arginine ester, marinobufagin 3-suberoyl arginine ester, bufalin 3-adipoyl arginine, marinobufagin, bufotalinin, and bufalitoxin. These findings indicate that R. icterica parotoid secretion is active in both of the preparations examined, with the activity in oviduct possibly being mediated by bufadienolides.

The effect of polychlorinated biphenyls (PCBs) on bovine oviductal contractions and LIF synthesis during estrous cycle, in vitro studies

Polychlorinated biphenyls (PCBs) are a group of synthetic xenobiotics that have been used in many industrial applications. Currently, PCBs are among the most prominent environmental contaminants. Previously we showed that PCBs impair secretion of prostaglandins (PGs) at the oviduct. PGs are involved in the regulation of oviductal contractions and the synthesis of leukemia inhibitory factors LIF. Since oviductal contractions are crucial for gamete and embryo transport, and LIF is essential for embryo implantation, the direct effect of PCBs on oviductal motor activity and LIF mRNA expression were investigated. Oviductal strips and cells were taken from cows during the estrous cycle and were treated with PCBs at concentrations close to their environmental ranges. All the studied PCBs decreased the force of the contractions of the longitudinal and circular muscles of the isthmus. Additionally, these PCBs decreased the amplitude of the longitudinal muscle of the oviduct. Moreover, PCB-30-OH and PCB-153 increased the mRNA expression of LIF. Since PCBs inhibit the motor function of the oviduct and stimulate the synthesis of LIF, it is possible that PCBs can slow gamete or embryo transport and increase the potential for pathological embryo implantation in the oviduct.

Mechanism of luminal ATP activated chloride secretion in a polarized epithelium

There are both secretory and absorptive pathways working in tandem to support ionic movement driving fluid secretion across epithelia. The mechanisms exerting control of fluid secretion in the oviduct is yet to be fully determined. This study explored the role of apical or luminal extracellular ATP (ATPe)-stimulated ion transport in an oviduct epithelium model, using the Ussing chamber short-circuit current (Isc) technique. Basal Isc in oviduct epithelium in response to apical ATPe comprises both chloride secretion and sodium absorption and has distinct temporal phases. A rapid transient peak followed by a sustained small increase above baseline. Both phases of the apical ATPe Isc response are sensitive to anion (HCO3-, Cl-) and cation (Na+) replacement. Additionally, the role of apical chloride channels, basolateral potassium channels and intracellular calcium in supporting the peak Isc current was confirmed. The role of ATP breakdown to adenosine resulting in the activation of P2 receptors was supported by examining the effects of non-hydrolyzable forms of ATP. A P2YR2 potency profile of ATP = UTP > ADP was generated for the apical membrane, suggesting the involvement of the P2YR2 subtype of purinoceptor. A P2X potency profile of ATP = 2MeSATP > alpha,beta-meATP > BzATP was also generated for the apical membrane. In conclusion, these results provide strong evidence that purinergic activation of apical P2YR2 promotes chloride secretion and is thus an important factor in fluid formation by the oviduct.

Involvement of P38 and ERK1/2 in mitochondrial pathways independent cell apoptosis in oviduct magnum epithelial cells of layers challenged with vanadium

Vanadium (V) can induce cell apoptosis in layers' oviduct resulting in egg quality reduction. In this study, we investigated the relationship between the mitogen-activated protein kinase (MAPK)-signaling pathway and V-induced apoptosis in poultry oviduct magnum epithelial cells (OMECs). Cultured OMECs were divided into 8 treatment groups: 0 μmol/L V (control), 100 μmol/L V (V100), V100 + P38MAPK inhibitor (SB203580), SB203580, V100 + extracellular signal-regulated kinases 1 and 2 (ERK1/2) inhibitor (U0126), U0126, V100 + c-JUN NH₂ -terminal kinase (JNK) inhibitor (SP600125), and SP600125. The OMECs were pretreated with the MAPK inhibitors before their treatment with V100 for 12 h. V100 increased the apoptosis of OMECs (P < .05), while 3 MAPK inhibitors suppressed V100-induced apoptosis P < .05); V100 enhanced the depolarization of △ψm (P < .05), and SB203580 and U0126 alleviated the V100-induced △ψm decrease (P < .05); V100 downregulated B-cell lymphoma-2 (Bcl-2) and poly [Adenosine diphosphate ribose] polymerase 1 (PARP1) mRNA expression (P < .05), meanwhile it upregulated Bcl-2 associated x (Bax), Apaf1, cytochrome C (CytC) and cysteine aspartase (caspase) 3, 8, 9 mRNA expression (P < .05). All MAPKs inhibitors alleviated the up-regulation of V100 for Bax and caspase 3 mRNA expression and down-regulation of V100 for Bcl-2 expression (P < .05). SB203580 and U0126 upregulated CytC expression treated by V100 (P < .05), except SP600125, while SB203580 administration resulted in a similar upregulation of PARP1 expression (P < .05). SP600125 can alleviated V triggered p-P38MAPK (phosphor-P38), p-ERK1/2 (phosphor-ERK1/2), p-JNK (phosphor-JNK) increase on OME cells, and SB203580 and U0126 had a similar response to phosphor-P38 and p-JNK (P < .05). It concluded that V-induced apoptosis in OMECs through the activation of P38 and ERK1/2, and by increasing the ratio of Bax/Bcl-2, which resulted in △ψm decrease, CytC release into the cytosol; consequently caspase 3 is recruited and activated, PARP1 is cleaved, eventually leading to apoptosis.

Sublethal Effects of Solanum nigrum Fruit Extract and Its Pure Glycoalkaloids on the Physiology of Tenebrio molitor (Mealworm)

BACKGROUND

Solanaceae plants produce glycoalkaloids (GAs) that affect various physiological processes of herbivorous insects and they are being tested as potential alternatives for synthetic pesticides. They cause lethal and sublethal effects. Nevertheless, their mode of action remains unclear. Therefore, we examined the effects of Solanum nigrum fruit extracts and pure glycoalkaloids on a model beetle, Tenebrio molitor.

METHODS

Plant extracts or pure alkaloids were added to the food of the larvae for three days. The lipid, glycogen, and protein content in the fat body and the midgut were determined, and the contractility of the heart, hindgut, and oviduct muscles was tested using the video-microscopy technique. Finally, the ultrastructure of the fat body and the midgut was observed using electron microscopy.

RESULTS

No lethal effects were noted. Sublethal changes were observed in the content of biomolecules, malformations of organelles, chromatin condensation, and heart and oviduct contractility. The observed effects differed between the tested glycoalkaloids and the extract.

CONCLUSIONS

Both the extract and pure GAs have a wide range of effects that may result in impaired development, food intake, and reproduction. Some early effects may be used as bioindicators of stress. The effects of the extract and pure alkaloids suggest that the substances produced by the plant may act additively or synergistically.

In Vitro Mimicking of Estrous Cycle Stages: Dissecting the Impact of Estradiol and Progesterone on Oviduct Epithelium

We have previously mimicked the morphological and functional changes occurring in the oviduct epithelium during the estrous cycle in vitro by using an air-liquid interface (ALI) culture system and basolateral application of 17β-estradiol (E2) and progesterone (P4). In the current study we aimed to explore the transcriptomic changes elicited by E2 and P4 together during estrous cycle simulation and to dissect the individual effects of E2 and P4 on oviduct epithelium physiology. Primary porcine oviduct epithelial cells (POECs) (N = 6 animals) were cultured at the ALI. After differentiation for 11 days, we sequentially simulated diestrus (10 days) and estrus (2.5 days) by adding serum levels of E2 and P4 to the basolateral compartment either in combination (mix trial) or separately (P4 trial and E2 trial, respectively). Cell response was evaluated by microarray analysis (mix and P4 trials), quantitative RT-PCR, and histomorphometry (all trials). When we compared simulated diestrus with estrus stage in the mix trial, there were 169 (142 upregulated and 27 downregulated) differentially expressed genes (DEGs; fold change ≥1.5). In the P4 trial, 108 DEGs (83 upregulated and 25 downregulated) were detected. Gene enrichment analysis revealed that immune-related pathways were exclusively affected in the mix trial. In both mix and P4 trials, POECs exhibited in vivo-like morphological changes regarding epithelium height and portion of ciliated cells. However, E2 alone did not trigger morphological changes. We deduce that P4 mainly drives structural variations, and E2 is imperative for regulating immune function of the oviduct epithelium during estrous cycle.

Effects of Levonorgestrel and progesterone on Oviductal physiology in mammals

BACKGROUND

Our previous study indicated that emergency contraception, including levonorgestrel and progesterone, could lead to ectopic pregnancy following contraception failure. However, our understanding of the effects of levonorgestrel and progesterone on oviductal physiology is limited.

METHODS

The receptivity of the fallopian tubal epithelium after levonorgestrel and progesterone treatment was examined through western blots for receptivity markers and JAr-spheroid-fallopian tubal epithelial cell attachment assays. The ciliary beat frequency was analyzed using an inverted bright-field microscope. Furthermore, an in vivo animal model of embryo-tubal transplantation was also studied to determine the effects of levonorgestrel- and progesterone-induced ciliary beat reduction.

RESULTS

Our results showed that levonorgestrel and progesterone did not change the levels of fallopian tubal epithelial cell receptive markers, including LIF, STAT3, IGFBP1, ITGB3, MUC1, and ACVR1B, or affect JAr-spheroid implantation. However, levonorgestrel and progesterone reduced the ciliary beat frequency in fallopian tubes in a dose-dependent manner. An in vivo model also showed that levonorgestrel and progesterone could lead to embryo retention in the oviducts.

CONCLUSIONS

These findings show that levonorgestrel and progesterone can reduce the ciliary beat frequency without altering receptivity, indicating a possible mechanism for progesterone- or levonorgestrel-induced tubal pregnancy.

Bisphenol A disrupts the temporal pattern of histofunctional changes in the female reproductive tract of Caiman latirostris

Recently, we have described the ontogeny of histofunctional differentiation changes in the oviduct of Caiman latirostris. The expression of estrogen receptor alpha and progesterone receptor shows that the caiman oviduct could be a target of the action of xenoestrogens such as the widely environmentally present Bisphenol A (BPA), early in life. The aims of this study were: to complement oviduct characterization by establishing the ontogenetic changes in androgen receptor (AR) expression and assessing the effects of early postnatal exposure to 17-β-estradiol (E2) or BPA on the histofunctional features of the oviduct. AR was expressed in all the stages studied. The spatial pattern of AR immunostaining changed from neonatal to juvenile caimans. In the luminal epithelium, changes were at the subcellular level, from cytoplasmic to nuclear. In the subepithelium, although both cytoplasmic and nuclear AR expression was observed, changes were mainly at tissue level, from the subepithelial compartment to the outer muscular layer. The oviduct was highly sensitive to E2 and BPA at the early postnatal developmental stage. E2- and BPA-exposed caimans showed increased luminal epithelial height and higher proliferative activity. Changes in histomorphological features (measured by a scoring system), steroid hormone receptors, collagen remodeling and muscle-associated proteins suggest a precocious oviduct histofunctional differentiation in E2- and BPA-exposed caimans. The modification of the temporal pattern of oviductal biomarkers suggests that organizational changes could impair C. latirostris reproductive health later in life. The alterations in the caiman female reproductive tract exposed to BPA highlight the importance of preserving aquatic environments from plastic pollution.

Effect of estrogen on prostaglandin synthetase in bovine oviduct smooth muscle

Gamete and embryo transport is an important function of the oviduct. This type of transport involves both smooth muscle contraction and epithelial cell secretions, and the former is mediated by prostaglandins (PGs) and their receptors. Our objective was to study the regulation of prostaglandin synthetase (prostaglandin-endoperoxide synthase-1 (PTGS1), prostaglandin-endoperoxide synthase-2 (PTGS2), mPGES-1, mPGES-2, cPGES, and PGFS) by estradiol (E₂) in bovine oviduct smooth muscle. Prostaglandin synthetase mRNA and protein expression were investigated using real-time RT-PCR and Western blot analyses, respectively. Prostaglandin synthetase mRNA and protein expression were increased in oviductal smooth muscle tissue after treatment with different concentrations of estradiol for various time periods. The results indicated that there was no increase in expression observed after treatment with fulvestrant, a selective antagonist of the E₂ receptor, indicating that E₂ interacts with specific E₂ nuclear receptors to upregulate PTGS1, PTGS2, mPGES-1, and PGFS expression. In conclusion, E₂ increases PTGS1, mPGES-1, and PGFS mRNA and protein expression in bovine oviductal smooth muscle when added for different periods of time and at different concentrations. Additionally, E₂ is transported intracellularly and interacts with specific E₂ nuclear receptors to increase PTGS1, PTGS2, mPGES-1 and PGFS expression.

Downregulation of LH and FSH receptors after hCG and eCG treatments in the porcine oviduct

The influence of induction of ovulation and superovulation with eCG and hCG on LH and FSH receptor levels in porcine oviducts on day 3 postcoitum was studied. In experiment I, gilts were assigned into cyclic (control; n = 5) and inseminated (n = 5) groups. In experiment II, there were 3 groups of animals: inseminated (n = 5), induced ovulation/inseminated (750 IU eCG, 500 IU hCG; n = 5) and superovulated/inseminated (1500 IU eCG, 1000 IU hCG; n = 5) gilts. Oviduct tissues were collected 3 d after insemination or PBS infusion. The messenger RNA (mRNA) expression of FSH receptor (FSHR) and luteinizing hormone/chorionic gonadotropin receptor (LH/CGR) was measured by real-time reverse transcription PCR and protein levels using Western blots. Localization of LH/CGR and FSHR-positive cells was studied by immunohistochemical staining. Insemination by itself did not influence mRNA and protein levels of LH/CGR. However, FSHR mRNA expression in the isthmus and ampulla of the oviduct was affected by insemination (P < 0.05). Similarly, insemination decreased FSHR protein level in the isthmus (P < 0.05). Stimulation with hCG and eCG did not affect LH/CGR and FSHR mRNA expression, either in the isthmus or in the ampulla. Nevertheless, superovulation decreased LH/CGR protein level in the oviductal ampulla (P < 0.05) in comparison with inseminated gilts. Similarly, protein levels of FSHR in the oviductal ampulla decreased after superovulation (P < 0.05). LH/CGR-positive cells were observed in the mucosa as well as in smooth muscle cells of both parts of the oviduct. Follicle-stimulating hormone receptor-positive cells were observed in smooth muscle cells and blood vessels of the isthmus. In the ampulla, FSHR-positive cells were observed in the smooth muscle as well as in the mucosa. Summarizing, the present study revealed for the first time that stimulation with eCG and hCG, especially in high doses, can change LH/CGR and FSHR levels in porcine oviducts. This may in turn alter many signaling pathways, eg, PGs or vascular endothelial growth factor synthesis, and consequently disturb the oviductal environment, with possible detrimental effects on fertilization and/or embryonic development.

Ethanol impedes embryo transport and impairs oviduct epithelium

Most studies have demonstrated that alcohol consumption is associated with decreased fertility. The aim of this study was to investigate the effects of alcohol on pre-implantation embryo transport and/or early embryo development in the oviduct. We reported here that ethanol concentration-dependently suppressed the spontaneous motility of isolated human oviduct strips (EC50 50±6mM), which was largely attenuated in the present of L-NAME, a classical nitric oxide synthase(NOS) competitive inhibitor. Notably, either acute or chronic alcohol intake delayed egg transport and retarded early development of the embryo in the mouse oviduct, which was largely rescued by co-administration of L-NAME in a acute alcohol intake group but not in chronic alcohol intake group. It is worth mentioning that the oviductal epithelium destruction was verified by scanning electron microscope (SEM) observations in chronic alcohol intake group. In conclusion, alcohol intake delayed egg transport and retarded early development of the embryo in the oviduct by suppressing the spontaneous motility of oviduct and/or impairing oviductal epithelium. These findings suggested that alcohol abuse increases the incident of ectopic pregnancy.

Atrazine triggers developmental abnormality of ovary and oviduct in quails (Coturnix Coturnix coturnix) via disruption of hypothalamo-pituitary-ovarian axis

There has been a gradual increase in production and consumption of atrazine (ATR) in agriculture to meet the population rising demands. Female reproduction is necessary for growth and maintenance of population. However, ATR impact on females and particularly ovarian developmental toxicity is less clear. The aim of this study was to define the pathways by which ATR exerted toxic effects on ovarian development of ovary and hypothalamo-pituitary-ovarian (HPO) axis. Female quails were dosed by oral gavage from sexual immaturity to maturity with 0, 50, 250 and 500 mg ATR/kg/d for 45 days. ATR had no effect on mortality but depressed feed intake and growth and influenced the biochemical parameters. Notably, the arrested development of ovaries and oviducts were observed in ATR-exposed quails. The circulating concentrations of E2, P, LH and PRL were unregulated and FSH and T was downregulated in ATR-treated quails. The mRNA expression of GnRH in hypothalamo and LH in pituitary and FSH in ovary was downregulated significantly by ATR exposure and FSH and PRL in pituitary were upregulated. ATR exposure upregulated the level of P450scc, P450arom, 3β-HSD and 17β-HSD in ovary and downregulated ERβ expression in female quails. However, ATR did not change ERα expression in ovary. This study provides new insights regarding female productive toxicology of ATR exposure. Ovary and oviduct in sexually maturing females were target organs of ATR-induced developmental toxicity. We propose that ATR-induced developmental abnormality of ovary and oviduct is associated with disruption of gonadal hormone balance and HPO axis in female quails.

Estrogen regulation of phosphoserine phosphatase during regression and recrudescence of female reproductive organs

Phosphoserine phosphatase (PSPH) is a well-known mediator of l-serine biosynthesis in a variety of tissues and its dysregulation causes various diseases, specifically most cancers. However, little is known about the expression and hormonal regulation of PSPH gene in the female reproductive tract. Therefore, in the current study, we focused on relationships between PSPH expression and estrogen during growth, development, differentiation, remodeling and recrudescence of the chicken oviduct and in the progression of epithelial-derived ovarian carcinogenesis in laying hens. The results revealed that PSPH mRNA and protein levels increased in the glandular (GE) and luminal epithelial (LE) cells in the developing oviduct of chicks treated with exogenous estrogen. Additionally, PSPH mRNA and protein expression was up-regulated in GE and LE of the oviduct in response to endogenous estrogen during the recrudescence phase after induced molting. Furthermore, PSPH mRNA and protein were predominantly detected in GE of cancerous, but not normal ovaries. In conclusion, PSPH is a novel estrogen-responsive gene involved in development of the oviduct of chicks and recrudescence of the oviduct of laying hens after molting. PSPH is also a potential target molecule that may help elucidate mechanism responsible for the progression of epithelial cell-derived ovarian carcinogenesis and be of use in therapeutic applications as a biomarker for early diagnosis of epithelial cell-derived ovarian cancer in laying hen as well as women.

Myoinhibitors controlling oviduct contraction within the female blood-gorging insect, Rhodnius prolixus

Muscle activity can be regulated by stimulatory and inhibitory neuropeptides allowing for contraction and relaxation. There are various families of neuropeptides that can be classified as inhibitors of insect muscle contraction. This study focuses on Rhodnius prolixus and three neuropeptide families that have been shown to be myoinhibitors in insects: A-type allatostatins, myoinhibiting peptides (B-type allatostatins) and myosuppressins. FGLa/AST-like immunoreactive axons and blebs were found on the anterior of the dorsal vessel and on the abdominal nerves. FGLa/AST-like immunoreactive axons were also seen in the trunk nerves and on the bursa. The effects of RhoprAST-2 (FGLa/AST or A-type allatostatins) and RhoprMIP-4 (MIP/AST or B-type allatostatins) were similar, producing dose-dependent inhibition of R. prolixus spontaneous oviduct contractions with a maximum of 70% inhibition and an EC50 at approximately 10(-8)M. The myosuppressin of R. prolixus (RhoprMS) has an unusual FMRFamide C-terminal motif (pQDIDHVFMRFa) as compared to myosuppressins from other insects. Quantitative PCR results show that the RhoprMS receptor transcript is present in adult female oviducts; however, RhoprMS does not have an inhibitory effect on R. prolixus oviduct contractions, but does have a dose-dependent inhibitory effect on the spontaneous contraction of Locusta migratoria oviducts. SchistoFLRFamide, the myosuppressin of Schistocerca gregaria and L. migratoria, also does not inhibit R. prolixus oviduct contractions. This implies that FGLa/ASTs and MIP/ASTs may play a role in regulating egg movement within the oviducts, and that the myosuppressin although myoinhibitory on other muscles in R. prolixus, does not inhibit the contractions of R. prolixus oviducts and may play another role in the reproductive system.

Expression and regulation of avian cathepsin L in the oviduct during molting

Cathepsins (CTSs) are peptidases that have biological roles in degrading extracellular matrix, catabolism of intracellular proteins, and processing of pro-hormones. Of these, cathepsin L (CTSL) is closely associated with morphological changes in reproductive organs required for proper function in mammals, including humans and mice, but little is known about CTSL in avian species. In the present study, the expression of CTSL was investigated in the oviduct of hens during regression and recrudescence in response to molting. Our results revealed that expression of CTSL mRNA increased (P<0.001) when the oviduct underwent regression during the molting period in hens. In situ hybridization and immunohistochemial analyses detected CTSL mRNA and protein predominantly in the luminal (LE) and glandular epithelia (GE) during regression of the oviduct, but not during regeneration of the oviduct. Expression of CTSL decreased in the oviduct of chicks treated with diethylstilbestrol (DES, a synthetic estrogen agonist). Furthermore, we discovered four miRNAs including miR-23b, miR-551, miR-1464 and miR-1803 that regulate expression of the CTSL gene at the post-transcriptional level, which suggests that CTSL mRNA can be regulated by specific miRNAs via 3'-UTR in chickens. Results of the present research suggest that estrogen regulates expression of CTSL during regression of the oviduct during molting and that down-regulation of CTSL is likely a prerequisite for the normal regeneration of oviductal tissues following molting in laying hens.

Avian SERPINB12 expression in the avian oviduct is regulated by estrogen and up-regulated in epithelial cell-derived ovarian carcinomas of laying hens

Serine protease inhibitors (SERPINs) are involved in a variety of biological processes such as blood clotting, angiogenesis, immune system, and embryogenesis. Although, of these, SERPINB12 is identified as the latest member of clade B in humans, little is known of it in chickens. Thus, in this study, we investigated SERPINB12 expression profiles in various tissues of chickens and focused on effects of steroid hormone regulation of its expression. In the chicken oviduct, SERPINB12 mRNA and protein are abundant in the luminal (LE) and glandular (GE) epithelia of the magnum in response to endogenous or exogenous estrogen. Furthermore, SERPINB12 mRNA and protein increase significantly in GE of cancerous ovaries of laying hens with epithelia-derived ovarian cancer. Collectively, these results indicate that SERPINB12 is a novel estrogen-stimulated gene that is up-regulated by estrogen in epithelial cells of the chicken oviduct and that it is a potential biomarker for early detection of ovarian carcinomas in laying hens and women.

Ornithokinin (avian bradykinin) from the skin of the Chinese bamboo odorous frog, Odorrana versabilis

One of the most widespread and abundant families of pharmacologically active peptides in amphibian defensive skin secretions is the bradykinins and related peptides. Despite retaining certain primary structural attributes that assign them to this peptide family, bradykinins and related peptides are unique among amphibian skin peptides in that they exhibit a wide range of primary structural variations, post-translational modifications and/or N-terminal or C-terminal extensions. Initially it was believed that their high degree of primary structural heterogeneity was reflective of random gene mutations within species, but latterly, there is an increasing body of evidence that the spectrum of structural modifications found within this peptide family is reflective of the vertebrate predator spectrum of individual species. Here we report the discovery of ornithokinin (avian bradykinin - Thr(6) , Leu(8) -bradykinin) in the skin secretion of the Chinese bamboo odorous frog, Odorrana versabilis. Molecular cloning of its biosynthetic precursor-encoding cDNA from a skin secretion-derived cDNA library revealed a deduced open-reading frame of 86 amino acid residues, encoding a single copy of ornithokinin towards its C-terminus. The domain architecture of this ornithokinin precursor protein was consistent with that of a typical amphibian skin peptide and quite different to that of the ornithokininogen from chicken plasma. Ornithokinin was reported to induce hypotension in the chicken and to contract the chicken oviduct but to have no obvious effect on the rat uterus. However, in this study, synthetic ornithokinin was found to contract the rat ileum (EC50  = 539 nM) and to increase contraction frequency in the rat uterus (EC50  = 1.87 μM).

Hormonal regulation of beta-catenin during development of the avian oviduct and its expression in epithelial cell-derived ovarian carcinogenesis

Beta-catenin (CTNNB1) is a dual function molecule that acts as a key component of the cadherin complex and WNT signaling pathway. It has a crucial role in embryogenesis, tumorigenesis, angiogenesis and progression of metastasis. Recently, it has been suggested that the CTNNB1 complex is a major regulator of development of the mouse oviduct and uterus. However, little is known about the CTNNB1 gene in chickens. Therefore, in this study, we focused on the CTNNB1 gene in the chicken reproductive tract and hormonal control of its expression in the chicken oviduct. CTNNB1 was localized specifically to the luminal and glandular epithelium of the four segments of chicken oviduct and DES (diethylstilbestrol, a synthetic non-steroidal estrogen) increased its expression primarily in LE of the magnum. In addition, CTNNB1 mRNA and protein were expressed abundantly in glandular epithelium of endometrioid-type ovarian carcinoma, but not in normal ovaries. Moreover, CTNNB1 expression was post-transcriptionally regulated via its 3'-UTR by binding with target miRNAs including miR-217, miR-1467, miR-1623 and miR-1697. Collectively, these results indicate that CTNNB1 is a novel gene regulated by estrogen in epithelial cells of the chicken oviduct and that it is also abundantly expressed in epithelial cells of endometrioid-type ovarian carcinoma suggesting that it could be used as a marker for diagnosis of ovarian cancer in laying hens and women.

Morphology of the oviduct of commercial egg-laying hens supplemented with organic minerals

OBJECTIVE

To analyze the morphology of the oviduct of commercial egg-laying hens supplemented with organic minerals.

STUDY DESIGN

A total of 2,400 Dekalb hens at 42 weeks of age were included in the study. Throughout the period of the experiment (10 months, divided into 4 periods of 10 weeks each) a supplement was administered. The animals were divided at random into 2 groups, each consisting of 1,200 hens: Group I, the control group of hens that did not receive the supplement, and Group II, the group of hens that were administered the supplement. The morphology of the oviduct was evaluated; all tests were performed from 52 to 82 weeks. After the hens were sacrificed by cervical dislocation, fragments of the oviduct were collected, 10 hens per group, which were fixed in Bouin liquid for 6 hours. Then they were processed and analyzed for light microscopy.

RESULTS

Analyzing the hens' oviduct, there was no change in weight of organs, but microscopy revealed that the hens' oviduct epithelium in Group II was preserved, with uniform cilia.

CONCLUSION

Based on our results we can conclude that the organic mineral supplementation causes an improvement in hens' oviduct morphology.

The duration of Chlamydia muridarum genital tract infection and associated chronic pathological changes are reduced in IL-17 knockout mice but protection is not increased further by immunization

IL-17 is believed to be important for protection against extracellular pathogens, where clearance is dependent on neutrophil recruitment and local activation of epithelial cell defences. However, the role of IL-17 in protection against intracellular pathogens such as Chlamydia is less clear. We have compared (i) the course of natural genital tract C. muridarum infection, (ii) the development of oviduct pathology and (iii) the development of vaccine-induced immunity against infection in wild type (WT) BALB/c and IL-17 knockout mice (IL-17-/-) to determine if IL-17-mediated immunity is implicated in the development of infection-induced pathology and/or protection. Both the magnitude and duration of genital infection was significantly reduced in IL-17-/- mice compared to BALB/c. Similarly, hydrosalpinx was also greatly reduced in IL-17-/- mice and this correlated with reduced neutrophil and macrophage infiltration of oviduct tissues. Matrix metalloproteinase (MMP) 9 and MMP2 were increased in WT oviducts compared to IL-17-/- animals at day 7 post-infection. In contrast, oviducts from IL-17-/- mice contained higher MMP9 and MMP2 at day 21. Infection also elicited higher levels of Chlamydia-neutralizing antibody in serum of IL-17-/- mice than WT mice. Following intranasal immunization with C. muridarumMajor Outer Membrane Protein (MOMP) and cholera toxin plus CpG adjuvants, significantly higher levels of chlamydial MOMP-specific IgG and IgA were found in serum and vaginal washes of IL-17-/- mice. T cell proliferation and IFNγ production by splenocytes was greater in WT animals following in vitro re-stimulation, however vaccination was only effective at reducing infection in WT, not IL-17-/- mice. Intranasal or transcutaneous immunization protected WT but not IL-17-/- mice against hydrosalpinx development. Our data show that in the absence of IL-17, the severity of C. muridarum genital infection and associated oviduct pathology are significantly attenuated, however neither infection or pathology can be reduced further by vaccination protocols that effectively protect WT mice.

Avian WNT4 in the female reproductive tracts: potential role of oviduct development and ovarian carcinogenesis

The wingless-type MMTV integration site family of proteins (WNTs) is highly conserved secreted lipid-modified signaling molecules that play a variety of pivotal roles in developmental events such as embryogenesis, tissue homeostasis and cell polarity. Although, of these proteins, WNT4 is known to be involved in genital development in fetuses of mammalian species, its role is unknown in avian species. Therefore, in this study, we investigated expression profiles, as well as hormonal and post-transcriptional regulation of WNT4 expression in the reproductive tract of female chickens. Results of this study demonstrated that WNT4 is most abundant in the stromal and luminal epithelial cells of the isthmus and shell gland of the oviduct, respectively. WNT4 is also most abundant in the glandular epithelium of the shell gland of the oviduct of laying hens at 3 h post-ovulation during the laying cycle. In addition, treatment of young chicks with diethylstilbestrol (DES, a synthetic estrogen agonist) stimulated WNT4 only in the glandular epithelial cells of the isthmus and shell gland of the oviduct. Moreover, results of our study demonstrated that miR-1786 influences WNT4 expression via specific binding sites in its 3'-UTR. On the other hand, our results also indicate that WNT4 is expressed predominantly in the glandular epithelium of cancerous ovaries, but not in normal ovaries of hens. Collectively, these results indicate cell-specific expression of WNT4 in the reproductive tract of chickens and that it likely has crucial roles in development and function of oviduct as well as initiation of ovarian carcinogenesis in laying hens.

Expression and regulation of beta-defensin 11 in the oviduct in response to estrogen and in ovarian tumors of chickens

Avian beta-defensins (AvBDs), also known as gallinacins, are small cationic peptides having three cysteine disulfide bonds between their cysteine residues. They play essential roles in the innate immune system as well as stimulate proliferation of epithelial cells and fibroblasts. Although we found the avian homolog of human beta-defensin 11 to be highly expressed in chicks treated with the diethylstilbestrol (DES, a synthetic estrogen agonist), little is known about the hormonal and transcriptional regulation of AvBD-11 in the chicken oviduct and its expression in cancerous ovaries of chickens. Results of this study of young chicks revealed that DES induced AvBD-11 mRNA and protein in the oviduct, specifically luminal and glandular epithelial cells. In addition, microRNA-1615 was discovered to influence AvBD-11 expression via its 3'-UTR which suggests post-transcriptional regulation of AvBD-11 expression in chickens. Furthermore, we compared the expression patterns of the AvBD-11 gene in normal and cancerous ovaries from laying hens which are models for human epithelial ovarian cancer. Our results demonstrated that AvBD-11 is most abundant in the glandular epithelium of endometrioid-type ovarian tumors, but not normal ovaries of laying hens. Collectively, these results suggest that AvBD-11 is an estrogen-induced gene during oviduct development and that it may be used as a biomarker for diagnosis of ovarian cancer and for monitoring effects of therapeutics on progression of ovarian carcinogenesis.

Stromal liver kinase B1 [STK11] signaling loss induces oviductal adenomas and endometrial cancer by activating mammalian Target of Rapamycin Complex 1

Germline mutations of the Liver Kinase b1 (LKB1/STK11) tumor suppressor gene have been linked to Peutz-Jeghers Syndrome (PJS), an autosomal-dominant, cancer-prone disorder in which patients develop neoplasms in several organs, including the oviduct, ovary, and cervix. We have conditionally deleted Lkb1 in Müllerian duct mesenchyme-derived cells of the female reproductive tract and observed expansion of the stromal compartment and hyperplasia and/or neoplasia of adjacent epithelial cells throughout the reproductive tract with paratubal cysts and adenomyomas in oviducts and, eventually, endometrial cancer. Examination of the proliferation marker phospho-histone H3 and mammalian Target Of Rapamycin Complex 1 (mTORC1) pathway members revealed increased proliferation and mTORC1 activation in stromal cells of both the oviduct and uterus. Treatment with rapamycin, an inhibitor of mTORC1 activity, decreased tumor burden in adult Lkb1 mutant mice. Deletion of the genes for Tuberous Sclerosis 1 (Tsc1) or Tsc2, regulators of mTORC1 that are downstream of LKB1 signaling, in the oviductal and uterine stroma phenocopies some of the defects observed in Lkb1 mutant mice, confirming that dysregulated mTORC1 activation in the Lkb1-deleted stroma contributes to the phenotype. Loss of PTEN, an upstream regulator of mTORC1 signaling, along with Lkb1 deletion significantly increased tumor burden in uteri and induced tumorigenesis in the cervix and vagina. These studies show that LKB1/TSC1/TSC2/mTORC1 signaling in mesenchymal cells is important for the maintenance of epithelial integrity and suppression of carcinogenesis in adjacent epithelial cells. Because similar changes in the stromal population are also observed in human oviductal/ovarian adenoma and endometrial adenocarcinoma patients, we predict that dysregulated mTORC1 activity by upstream mechanisms similar to those described in these model systems contributes to the pathogenesis of these human diseases.

Peutz-Jeghers Syndrome patients have autosomal dominant mutations in the LKB1/STK11 gene and are prone to developing cancer, predominantly in the intestinal tract but also in other tissues, including the reproductive tracts and gonads. To elucidate the mechanisms disrupted by the loss of LKB1 in the reproductive tract, we have developed a mouse model with deletion of Lkb1 specifically in stromal cells of gynecologic tissues. These mice show stromal cell expansion and develop oviductal adenomas and endometrial cancer. Deletion of either Tsc1 or Tsc2 genes, which are mutated in patients with Tuberous Sclerosis Complex and whose protein products are indirect downstream targets of LKB1 signaling, resulted in some of the same defects observed in Lkb1 mutant mice. Activation of mammalian Target Of Rapamycin Complex 1 (mTORC1), a common effector of disrupted LKB1, TSC1, and TSC2 signaling, was observed in all mutant tissues examined, suggesting that uninhibited mTORC1 activity is necessary for the phenotypes. Suppression of mTORC1 signaling by rapamycin reduced tumor burden in Lkb1 mutant mice, confirming the link between dysregulation of mTORC1 to development of the Lkb1 mutant phenotype and suggesting that therapeutic targeting of LKB1/TSC1/TSC2/mTORC1 signaling would benefit human Peutz-Jeghers Syndrome and Tuberous Sclerosis patients with reproductive tract disease.

New myotropic and metabotropic actions of pyrokinins in tenebrionid beetles

Pyrokinins are a large family of insect neuropeptides exhibiting pleiotropic activity, but are predominantly myostimulatory hormones. In this study, four pyrokinins Tenmo-PK-1 (HVVNFTPRLa), Tenmo-PK-2 (SPPFAPRLa), Tenmo-PK-3 (HLSPFSPRLa) and Zopat-PK-1 (LPHYPRLa) from the neuro-endocrine system of two tenebrionid beetles, Tenebrio molitor and Zophobas atratus, were tested in homologous bioassays to evaluate their putative myotropic and glycaemic actions. The four investigated bioassays systems (the heart, oviduct, ejaculatory duct and hindgut) revealed species-specific and organ-specific myotropic actions for the pyrokinins tested. In most bioassays with both beetles, the peptides showed myostimulatory properties with different efficacy. However, the T. molitor heart is not sensitive to Tenmo-PK-1, Tenmo-PK-2 and Tenmo-PK-3, and one of the peptides Tenmo-PK-1, is myoinhibitory on the oviduct. Tenmo-PK-2, which is also present in Z. atratus, exerted an inhibitory effect on the contractions of the heart and ejaculatory duct muscles in this beetle. Such myoinhibitory properties of pyrokinins in insects are shown here for the first time. Only one of the peptides tested, Tenmo-PK-2, stimulated a hyperglycaemic response in the haemolymph of larvae of T. molitor and Z. atratus, and this effect suggests a possible additional metabotropic function of this peptide in beetles. The differences in the myotropic and glycaemic responses to pyrokinins suggest that these peptides modulate contractions of muscles from visceral organs and free sugar levels in the haemolymph of the beetles, through complex and species-specific mechanisms.

Differential expression of secreted phosphoprotein 1 in response to estradiol-17β and in ovarian tumors in chickens

Secreted phosphoprotein 1 (SPP1), a highly phosphorylated protein containing a polyaspartic acid sequence and a conserved RGD motif, plays important roles in physiological processes such as inflammatory responses, calcification, organ development, immune cell function and carcinogenesis. Results of the present study indicate expression of SPP1 mRNA in various organs such as oviduct, small intestine and kidney from chickens, particularly in the glandular epithelium (GE) of the shell gland and, to a lesser extent, in luminal epithelium (LE) of the infundibulum and magnum, and GE of the isthmus of the oviduct. We determined that DES (diethylstilbestrol, a synthetic nonsteroidal estrogen) decreases SPP1 expression in the oviduct and that SPP1 mRNA and protein are significantly more abundant in GE of ovarian endometrioid carcinoma, but not the other cancerous and normal ovaries of hens. Further, microRNA-140 was discovered to influence SPP1 expression via its 3'-UTR which suggests that post-transcriptional regulation influences SPP1 expression in chickens. Collectively, results of this study indicate that SPP1 is novel in that its expression is down-regulated by estrogen in epithelial cells of the chicken oviduct and that it is up-regulated in chicken ovarian endometrioid tumor that could be used for monitoring effects of therapies for this disease in laying hens.

Chicken pleiotrophin: regulation of tissue specific expression by estrogen in the oviduct and distinct expression pattern in the ovarian carcinomas

Pleiotrophin (PTN) is a developmentally-regulated growth factor which is widely distributed in various tissues and also detected in many kinds of carcinomas. However, little is known about the PTN gene in chickens. In the present study, we found chicken PTN to be highly conserved with respect to mammalian PTN genes (91–92.6%) and its mRNA was most abundant in brain, heart and oviduct. This study focused on the PTN gene in the oviduct where it was detected in the glandular (GE) and luminal (LE) epithelial cells. Treatment of young chicks with diethylstilbesterol induced PTN mRNA and protein in GE and LE, but not in other cell types of the oviduct. Further, several microRNAs, specifically miR-499 and miR-1709 were discovered to influence PTN expression via its 3′-UTR which suggests that post-transcriptional regulation influences PTN expression in chickens. We also compared expression patterns and CpG methylation status of the PTN gene in normal and cancerous ovaries from chickens. Our results indicated that PTN is most abundant in the GE of adenocarcinoma of cancerous, but not normal ovaries of hens. Bisulfite sequencing revealed that 30- and 40% of −1311 and −1339 CpG sites are demethylated in ovarian cancer cells, respectively. Collectively, these results indicate that chicken PTN is a novel estrogen-induced gene expressed mainly in the oviductal epithelia implicating PTN regulation of oviduct development and egg formation, and also suggest that PTN is a biomarker for epithelial ovarian carcinoma that could be used for diagnosis and monitoring effects of therapies for the disease.

Gonadotropin-induced changes in oviducal mRNA expression levels of sex steroid hormone receptors and activin-related signaling factors in the alligator

Oviducts respond to hormonal cues from ovaries with tissue proliferation and differentiation in preparation of transporting and fostering gametes. These responses produce oviducal microenvironments conducive to reproductive success. Here, we investigated changes in circulating plasma sex steroid hormones concentrations and ovarian and oviducal mRNA expression to an in vivo gonadotropin (FSH) challenge in sexually immature, five-month-old alligators. Further, we investigated differences in these observed responses between alligators hatched from eggs collected at a heavily-polluted (Lake Apopka, FL) and minimally-polluted (Lake Woodruff, FL) site. In oviducts, we measured mRNA expression of estrogen, progesterone, and androgen receptors and also beta A and B subunits which homo- or heterodimerize to produce the transforming growth factor activin. In comparison, minimal inhibin alpha subunit mRNA expression suggests that these oviducts produce a primarily activin-dominated signaling milieu. Ovaries responded to a five-day FSH challenge with increased expression of steroidogenic enzyme mRNA which was concomitant with increased circulating sex steroid hormone concentrations. Oviducts in the FSH-challenged Lake Woodruff alligators increased mRNA expression of progesterone and androgen receptors, proliferating cell nuclear antigen, and the activin signaling antagonist follistatin. In contrast, Lake Apopka alligators displayed a diminished increase in ovarian CYP19A1 aromatase expression and no increase in oviducal AR expression, as compared to those observed in Lake Woodruff alligators. These results demonstrate that five-month-old female alligators display an endocrine-responsive ovarian-oviducal axis and environmental pollution exposure may alter these physiological responses.

Tissue specific expression and estrogen regulation of SERPINB3 in the chicken oviduct

Serine protease inhibitors (SERPINs) comprise the largest superfamily of protease inhibitors and appear to be ubiquitously expressed in a variety of species. Of these, squamous cell carcinoma antigen 1 (SCCA1), also known as a SERPINB3, was first identified in squamous cell carcinoma tissue from the cervix of women. However, there is little known about the expression and hormonal regulation of SERPINB3 in chickens. Therefore, the avian SERPINB3 gene was compared with those of other species with respect to structure, phylogenetic evolution and tissue- and cell-specific expression in hens. Chicken SERPINB3 has moderate homology to mammalian SERPINB3 proteins (36-47%). Of particular note, SERPINB3 mRNA was most abundant in the chicken oviduct and cell-specific expression was in glandular (GE) and luminal (LE) epithelial cells of the oviduct of laying hens. Treatment of young chicks with DES (diethylstilbestrol, a synthetic nonsteroidal estrogen) induced SERPINB3 mRNA and protein in GE and LE, but not in other cell types of the oviduct. Western blot analyses determined that immunoreactive SERPINB3 protein was also increased by DES in LE and GE of the oviduct of chicks. Collectively, these results indicate that SERPINB3 is an estrogen-induced gene expressed only in LE and GE of the chicken oviduct and implicate SERPINB3 in regulation of oviduct development and egg formation.

Permanent oviduct posteriorization after neonatal exposure to the phytoestrogen genistein

BACKGROUND

Preimplantation embryo loss during oviduct transit has been observed in adult mice after a 5-day neonatal exposure to the phytoestrogen genistein (Gen; 50 mg/kg/day).

OBJECTIVE

We investigated the mechanisms underlying the contribution of the oviduct to infertility.

METHODS

Female mice were treated on postnatal days 1-5 with corn oil or Gen (50 mg/kg/day). We compared morphology, gene expression, and protein expression in different regions of the reproductive tracts of Gen-treated mice with those of control littermates at several time points.

RESULTS

Neonatal Gen treatment resulted in substantial changes in expression of genes that modulate neonatal oviduct morphogenesis, including Hoxa (homeobox A cluster), Wnt (wingless-related MMTV integration site), and hedgehog signaling genes. An estrogen receptor antagonist blocked these effects, indicating that they were induced by the estrogenic activity of Gen. Oviducts of adults treated neonatally with Gen had abnormal morphology and were stably "posteriorized," as indicated by altered Hoxa gene patterning during the time of treatment and dramatic, permanent up-regulation of homeobox genes (e.g., Pitx1, Six1) normally expressed only in the cervix and vagina.

CONCLUSIONS

Neonatal exposure to estrogenic environmental chemicals permanently disrupts oviduct morphogenesis and adult gene expression patterns, and these changes likely contribute to the infertility phenotype.

Early life progestin exposure causes arrested oocyte development, oviductal agenesis and sterility in adult Xenopus tropicalis frogs

Levonorgestrel (LNG) is a commonly used pharmaceutical progestin found in the environment. Information on the long-term toxicity of progestins following early life exposure is scant. We investigated the effects of developmental LNG exposure on sex differentiation, reproductive organ development and fertility in the model frog Xenopus tropicalis. Tadpoles were exposed to 0, 0.06 or 0.5nM LNG via the water from hatching until metamorphosis. At metamorphosis effects on gonadal differentiation were evaluated using a subsample of frogs. Remaining animals were held unexposed for nine months, at which time reproductive organ structure, function and fertility were determined. LNG exposure severely impaired oviduct and ovary development and fertility. All adult females in the 0.5nM group (n=10) completely lacked oviducts. They also displayed a significantly larger fraction of immature oocytes, arrested in meiotic prophase, than control females. Upon mating with unexposed males, only one of 11 LNG-exposed females laid eggs, whereas all control females did. No effects on testicular development, sperm count or male fertility were observed. At metamorphosis, no effects on sex ratio or gonadal histology were evident. The effects on ovarian and oviductal development were detected at adult age but not at metamorphosis, emphasising the importance of investigating the long-term consequences of developmental exposure. This is the first developmental reproductive toxicity study of a progestin in an aquatic vertebrate. Considering that several progestins are present in contaminated surface waters, further investigation into the sensitivity of frogs to progestins is warranted to understand the risk such compounds may pose to wild frog populations.

Histological changes in the uterus of the hens after embryonic exposure to bisphenol A and diethylstilbestrol

Many employed chemicals in industries have estrogenic hormone effects on organisms, and these are called as environmental estrogens. Environmental estrogens have adverse effects on development and function of reproductive organs of the birds. Bisphenol A (BPA) is one of the best known environmental estrogens widely found in plastic products. In this study, we injected BPA and the synthetic estrogen diethylstilbestrol (DES) in ovo and then examined and compared the effects of those on the uteri (shell gland) of the adult hens by histological methods. Five groups have been designed in the current study. Only vehicle substance was given in ovo to the control group and BPA (67 or 134 μg/g egg) and DES (0.02 or 0.2 μg/g egg) were administered in the experimental groups. Tissue specimens were taken from uteri of hens at 21 weeks of age, prior to the laying period. Estrogen receptor alpha (ERα) was immunohistochemically stained. It was observed that the hatching proportion in BPA (67 μg and 134 μg/g) was lesser than the other groups (P<0.01). Uterine tubular glandular density and thickness of tunica mucosa were found to have reduced (P<0.01) in BPA (134 μg/g) and DES (0.2 μg/g) groups, in comparison with those of the control and the other experimental groups. Uterine gland epithelium revealed positive immunoreaction for ERα. These findings suggested that administration of BPA and DES at high doses affected embryonic development in a negative way, and this adverse effect was seen less in adult period.

Adrenomedullin regulates sperm motility and oviductal ciliary beat via cyclic adenosine 5'-monophosphate/protein kinase A and nitric oxide

Cilium and flagellum beating are important in reproduction and defects in their motion are associated with ectopic pregnancy and infertility. Adrenomedullin (ADM) is a polypeptide present in the reproductive system. This report demonstrates a novel action of ADM in enhancing the flagellar/ciliary beating of human spermatozoa and rat oviductal ciliated cells. At the concentration found in the seminal plasma, it increases the progressive motility of spermatozoa. ADM binds to its classical receptor, calcitonin receptor-like receptor/receptor activity-modifying protein complex on spermatozoa. ADM treatment increases the protein kinase A activities, the cyclic adenosine monophosphate, and nitric oxide levels of spermatozoa and oviductal cells. Pharmacological activators and inhibitors confirmed that the ADM-induced flagella/ciliary beating was protein kinase A dependent. Whereas nitric oxide donors had no effect on sperm motility, they potentiated the motility-inducing action of protein kinase A activators, demonstrating for the first time the synergistic action of nitric oxide and protein kinase A signaling in flagellar/ciliary beating. The ADM-induced motility enhancement effect in spermatozoa also depended on the up-regulation of intracellular calcium, a known key regulator of sperm motility and ciliary beating. In conclusion, ADM is a common activator of flagellar/ciliary beating. The study provides a physiological basis on possible use of ADM as a fertility regulation drug.

Identification of a novel role for endothelins within the oviduct

Endothelins were first identified as potent vasoactive peptides; however, diversity in the biological function of these hormones is now evident. We have identified a novel role for endothelins: a requirement for these peptides within the oviduct during fertilization and/or early embryo development. In vivo, treatment after ovulation with a dual endothelin receptor antagonist (tezosentan) decreased the number of two-cell embryos that could be collected from within the oviducts. In vitro fertilization experiments showed that gamete viability and their ability to fertilize were not affected by treatment with this antagonist, suggesting that the effect observed in vivo was mediated by the oviduct itself. Expression of mRNA for all three isoforms of the endothelins and both receptor subtypes was detectable within the oviduct. Expression of mRNA for endothelin-3 was regulated by gonadotropins in epithelial cells of the oviduct and increased specifically within the isthmus of this structure. Immunostaining revealed localization of both endothelin receptors A and B to the columnar epithelial cells within the oviduct, suggestive of a local role for endothelins in the regulation of epithelial function and ultimately oviductal secretions. A microarray analysis revealed three likely endothelin-regulated protein networks for future analysis: the TGFbeta, IL-10, and CCAAT/enhancer-binding protein superfamilies. Overall, these results suggest a novel and requisite role for endothelins within the oviduct during fertilization and/or early embryo development.

Effects of tumor necrosis factor-alpha and nitric oxide on prostaglandins secretion by the bovine oviduct differ in the isthmus and ampulla and depend on the phase of the estrous cycle

To determine the possible roles of tumor necrosis factor-alpha (TNFalpha) and nitric oxide (NO) in the bovine oviduct, ampulla and isthmus collected during the estrous cycle were exposed for 18 h to TNFalpha, NO donor (NONOate), NO synthase inhibitors (L-NOARG, L-NAME and AMT) and oxytocin (OT) as a positive control. Prostaglandins (PGs) and NO(2)/NO(3) in conditioned media were measured. TNFalpha stimulated PGF(2alpha) secretion on Day 0 (onset of estrus = Day 0) and Days 2-3, in both the ampulla and isthmus, but on Days 18-20 only in ampulla. TNFalpha increased PGE(2) secretion in both fragments in each phase. NONOate did not affect PGF(2alpha) secretion on Days 18-20, whereas this NO donor stimulated PGF(2alpha) secretion in both fragments on Day 0 and Days 2-3. TNFalpha increased NO(2)/NO(3) production in every examined phase in the ampulla and on Days 2-3 in the isthmus. L-NAME lowered NO(2)/NO(3) production regardless of phase or fragment. L-NOARG and AMT lowered NO(2)/NO(3) production in both fragments on Day 0 and Days 2-3. The possible role of TNFalpha, NO or PGs on the oviductal contractility during the early-luteal phase was also examined. Neither TNFalpha nor NONOate influenced contractility in either fragment. Although PGF(2alpha) stimulated the contraction in both fragments, PGE(2) decreased it. When taken together, TNFalpha seems to play some role as a modulator of PGF(2alpha) and PGE(2) production and for transferring the embryo from the oviduct to the uterus by stimulating NO production in the bovine oviduct.

Reproductive and developmental effects of transovarian exposure to o,p'-DDT in Japanese quails

Avian species have the possible risk of embryonic exposure to persistent, lipophilic environmental contaminants, such as dichlorodiphenyltrichloroethane (DDT), by transfer of chemicals accumulated in mother birds to eggs. To model developmental and reproductive disorders of wild birds living in contaminated areas, we exposed Japanese quails in ovo to o,p'-DDT prior to incubation. A positive estrogenic substance diethylstilbestrol (DES; 1 and 10 ng/g of egg) and o,p'-DDT (1-100 microg/g of egg) were injected into the yolk before incubation. Treatment with o,p'-DDT (10 or 100 microg/g) but not with DES significantly reduced the hatchability of eggs. After sexual maturation, o,p'-DDT affected eggshell formation in female quails but had little influence on laying; high doses of o,p'-DDT significantly reduced eggshell strength, shell weight, and shell thickness, and several females treated with 100 microg o,p'-DDT/g laid eggs lacking shells. Diethylstilbestrol decreased egg production itself but had little effect on the eggshell. Both o,p'-DDT and DES caused dose-dependent shortening of the left oviduct and abnormal development of the right oviduct in females, while testis asymmetry was observed in males treated with a high dose of DES. In the uterus of the oviduct, the mRNAs for calcium-regulating factors osteopontin and calbindin D28K were reduced by both treatments, particularly that with o,p'-DDT. The results indicated that transovarian exposure to o,p'-DDT could bring about population declines in avian species through loss of fecundity caused by depression of hatchability and dysfunction of the reproductive tract.

Effects of calcium channel blockers on the female genital tract

Contractile activity and vascular resistance in the female genital tract are influenced by several smooth muscle tissues with individual mechanisms for control of mechanical activation. Calcium channel blockers have potent relaxant effects on preparations of human myometrium. The myometrial arteries utilize multiple sources of calcium for contractile activation, and excitation-contraction coupling in isolated vessels from non-pregnant uteri seems comparatively less sensitive to nifedipine than in corresponding myometrial preparations. Contractile activation of myometrial and placental arteries at term is inhibited by nitrendipine and nifedipine. Human oviductal smooth muscle depends on superficially bound calcium for mechanical activation, but only phasic contractions can be abolished by nifedipine, while tonic contractions induced by various agents are more resistant to the calcium channel blocker. Menstrual uterine contractions and pain are effectively counteracted by nifedipine in normal and dysmenorrhoeic women. Such therapy may represent an alternative principle in the treatment of dysmenorrhea. Nifedipine has potent relaxant effects on the mid-term pregnant and the post-partum uterus and calcium channel blockers may prove useful in the treatment of premature labor. Nifedipine and related compounds may further show effective in the treatment of pregnancy-associated hypertension. Whether such treatment in late pregnancy involves maintained or even improved placental perfusion could be assumed from in vitro data but needs further studies.

Selective activation of estrogen receptor alpha in Japanese quail embryos affects reproductive organ differentiation but not the male sexual behavior or the parvocellular vasotocin system

Estradiol is crucial for normal female differentiation in birds. Developmental effects of estrogen are believed to be mediated by slow genomic actions through the nuclear estrogen receptors alpha (ERalpha) and/or beta (ERbeta). Consequently, exogenous compounds that interfere with the ERs may disrupt sexual differentiation of the reproductive organs and of the brain areas controlling sexual behaviors. The present study was conducted to elucidate the role of ERalpha in xenoestrogen-induced disruption of sexual differentiation in the Japanese quail (Coturnix japonica). Embryonic treatment with the synthetic estrogen, ethinylestradiol (EE(2)), and with the ERalpha-selective agonist, propyl pyrazole triol (PPT), induced oviductal malformations in females and retention of oviducts in males. Both EE(2) and PPT caused weight asymmetry between left and right testes and reduced the cloacal gland area in males. EE(2) significantly reduced the copulatory behavior in males whereas PPT had no effect on this behavior. The sexually dimorphic parvocellular vasotocin-immunoreactive (VT-ir) system in the medial preoptic nucleus (POM), the lateral septum (SL) and the medial part of the nucleus of the stria terminalis (BSTm), was not affected by EE(2) or PPT. Our results suggest that xenoestrogen-induced effects on reproductive organ differentiation are mediated by ERalpha, whereas demasculinization of male copulatory behavior and the VT-ir system appears not to be induced by activation of ERalpha alone.

Reproductive tissue regression: Involvement of caspases, inducible nitric oxide synthase and nitric oxide during moulting in White Leghorn hens

Moulting is a natural physiological process where the reproductive system of birds undergoes complete remodeling in preparation for the next laying cycle. In domestic chickens, moulting is artificially induced by feed withdrawal to recycle the old laying flock for best profit margins. This has received severe criticism from animal welfare organizations, forcing several countries to stop this practice. Several alternative methods to feed withdrawal methods were developed but were found to produce inconsistent results. Understanding the actual mechanism of moulting would help in designing a new animal welfare friendly method. The present investigation attempted to study the molecular mechanism of moulting in White Leghorn hens. Eighty-four layers (75 weeks) were divided into two groups. The birds in the first group were subjected to moulting by feed withdrawal (FW) while the other group received high dietary Zn (ZnF) treatment for 10 days. Six birds from each group were sacrificed on 0, 1-4, 6 and 10 days of moulting and mRNA expression of caspases-1, -2 and iNOS, along with the apoptotic ladder pattern and nitric oxide (NO) in the ovary and oviduct, was investigated. The mRNA expression of iNOS was upregulated with a corresponding increase in NO levels. Caspases-1 and -2 were differentially upregulated in the ovary and oviduct of moulted birds. A constant decline in serum estradiol and progesterone levels was also observed. It can be concluded that the pattern of reproductive regression during moulting by the two methods is different, as the expression of genes studied in the present investigation is different.

Bacterial artificial chromosome transgenesis through pronuclear injection of fertilized mouse oocytes

In the mouse, conventional transgenes often produced unpredictable results mainly because they were too small to recapitulate a natural gene context. Bacterial artificial chromosomes (BACs) are large enough to encompass the natural context of most mammalian genes and consequently deliver more reliable recapitulations of their endogenous counterparts. Furthermore, recombineering methods now make it easy to engineer precise changes in a BAC transgene. Consequently, BACs have become the preferred vehicle for mouse transgenesis. Here, we detail methods for BAC transgenesis through pronuclear injection of fertilized oocytes.

Morphology and function of the rat oviduct: effects of thyroidectomy and thyroxine administration

The effect of thyroidectomy and thyroxine administration on the morphology and function of the oviduct was studied in 40 albino rats. Chronic administration of 10 microg/100g for 60 days resulted in atrophy of the smooth muscle and mucosal folds. The thyroidectomized rats had reduced smooth muscle wall thickness, the epithelium reduced from columnar to cuboidal; and also flattening of mucosal folding. The contractile responses to oxytocin, acetylcholine and indeed the spontaneous contraction in the four thyroid states suggest a dependence of oviductal contraction on adequate plasma level of thyroid hormone in the vicinity of the contracting smooth muscle of the oviduct. The results suggest that thyroid hormone affects the morphology and function of the oviduct.

Female reproductive toxicology of cadmium

The aim of this study was to determine effects of Cd on the structure of ovary, oviduct and uterus after an experimental administration. Animals were divided into three groups. In group A rabbits received cadmium i.p. and were killed after 48 h. In group C Cd was administered p.o. for 5 month. The group K was the control. Decreased relative volume of growing follicles and increased stroma after Cd administration were detected. The number of atretic follicles was significantly higher after administration of Cd. The most frequent ultrastructural alterations observed were undulation of external nuclear membrane, dilatation of perinuclear cistern and endoplasmic reticulum. In all studied types of cells mitochondria with altered structure were found. In the oviduct the highest amount of epithelium in the group with long-term Cd administration was found. Microscopic analysis showed oedematization of the oviduct tissue, caused by disintegration of the capillary wall. An electron microscopic analysis showed dilatation of perinuclear cistern. The intercellular spaces were enlarged and junctions between cells were affected. Mainly after a long-term cadmium administration nuclear chromatin disintegration was present. In the uterus a significant change was determined in the relative volume of glandular epithelium. Increase of stroma was a sign of uterus oedamatization caused by damage in the wall of blood vessels and subsequent diapedesis. After Cd administration alteration in uterus were less expressed, in comparison with ovary and oviduct. Alteration of nuclear chromatin contain following Cd administration suggests degenerative functional changes.

Effect of dietary daidzein on egg production, shell quality, and gene expression of ER-alpha, GH-R, and IGF-IR in shell glands of laying hens

Our previous studies demonstrated that dietary daidzein improves egg production in ducks during the late period of the laying cycle. The present study was aimed to investigate the effect of daidzein in laying hens, with more focus on eggshell quality. The expression of ER-alpha, GH-R, and IGF-IR mRNA in shell glands was determined to identify the target genes of daidzein action and to reveal the relationship between shell quality and profiles of gene expression in shell glands of laying hens. 1000 ISA hens, at 445 days of age, were allotted at random to two groups and given the basal diet with or without 10 mg of daidzein per kg diet for 9 weeks. Daidzein supplement significantly increased the egg laying rate and the feed conversion ratio. The eggshell thickness increased, while the percentage of cracked eggs decreased in daidzein-treated hens. Serum E2 and phosphate concentrations were not altered, but the level of serum Ca2+ and the tibia bone mineral density were significantly increased in the daidzein-treated group compared with their control counterparts. In parallel with the significant increase of oviduct weight, significant down-regulation of GH-R and IGF-IR mRNA and a trend of decrease in ERalpha mRNA expression in shell glands were observed in daidzein-treated hens. The results indicate that dietary daidzein improves egg laying performance and eggshell quality during the late (postpeak) laying stage of hens, which is associated with modulations in gene expression in the shell gland.

Long-term adverse effects of neonatal exposure to bisphenol A on the murine female reproductive tract

The developing fetus is uniquely sensitive to perturbation by chemicals with hormone-like activity. The adverse effects of prenatal diethylstilbestrol (DES) exposure are a classic example. Since concern has been mounting regarding the human health and environmental effects of bisphenol A (BPA), a high-production-volume chemical with estrogenic activity used in the synthesis of plastics, we investigated its long-term effects in an experimental animal model that was previously shown useful in studying the adverse effects of developmental exposure to DES. Outbred female CD-1 mice were treated on days 1-5 with subcutaneous injections of BPA (10, 100 or 1000 microg/kg/day) dissolved in corn oil or corn oil alone (Control). At 18 months, ovaries and reproductive tract tissues were examined. There was a statistically significant increase in cystic ovaries and cystic endometrial hyperplasia (CEH) in the BPA-100 group as compared to Controls. Progressive proliferative lesion (PPL) of the oviduct and cystic mesonephric (Wolffian) duct remnants were also seen in all of the BPA groups. More severe pathologies of the uterus following neonatal BPA treatment included adenomyosis, leiomyomas, atypical hyperplasia, and stromal polyps. These data suggest that BPA causes long-term adverse effects if exposure occurs during critical periods of differentiation.

Extracellular calcium induces activation of Ca(2+)/calmodulin-dependent protein kinase II and mediates spontaneous activation in rat oocytes

Ovulated rat oocytes are activated spontaneously soon after recovery from the oviducts. To investigate the kinetics and mechanism of rat oocyte spontaneous activation (OSA), we investigated the effect of aging in oviducts, hyaluronidase treatment, and extracellular and intracellular calcium, and examined the activity of CaMKII and the effect of its inhibitor on OSA. Oocyte aging in oviducts and hyaluronidase did not affect OSA. However, OSA was significantly decreased in calcium-free medium and in calcium-containing medium containing L-type calcium channel blocker and IP(3)R inhibitor. Moreover, significantly lower OSA was shown with an inhibitor of CaMKII. There was a significant increase of CaMKII activity at 30min after oocyte recovery and constitutively active CaMKII was located near the meiotic spindle in freshly recovered oocytes. Therefore, CaMKII is one of the upstream signals to activate rat oocytes spontaneously after recovery and rat oocytes respond very sensitively to extracellular calcium.

Expression of AGR-2 in Chicken Oviduct during Laying Period

The chicken oviduct is a dynamic organ that produces secretory proteins such as ovalbumin during the laying period. In this study, we identified oviduct-specific proteins in hens during the egg-laying period by proteomic analysis. Proteins extracted from the magnum of hens of different ages (5, 35, and 65 weeks) were analyzed by two-dimensional gel electrophoresis to compare the intensity of proteins among samples. Approximately 300 spots were detected on each gel. Based on the comparison of image gels, we found that the intensity of eight spots in 35-week magnums was increased at least by 2-fold compared with the others. Five of the eight spots were identified as calumenin, acidic ribosomal phosphoproteins (ARP), prohibitin, heart fatty acid-binding protein, and anterior gradient-2 (AGR-2). In particular, ARP and AGR-2 were highly expressed in 35- week magnums compared with 5- and 65-week magnums. In addition, the level of these proteins was consistent with their RNA levels. Expression of AGR-2 mRNA was detected in the mature magnum, whereas no signal was observed in premature tissue. Among various tissues, expression of AGR-2 mRNA was highest in the magnum, high in the isthmus, and five fold lower in muscle. It was undetectable in the liver and in other tissues (heart and kidney). However, the mRNA levels of other proteins were ubiquitous among tissues. In transcriptional activity of AGR-2, a 3.0 kb fragment of promoter region containing potential estrogen receptor binding sites had enhanced its activity strongly. In conclusion, these results suggest that AGR-2 has functional regulatory roles in the chicken oviduct during the egglaying period.

Neuropeptidergic control of Octopus oviducal gland

The oviducal gland of the female of Octopus vulgaris lies about halfway along the oviduct. Progesterone and 17beta-estradiol receptors have been immunolocalized in the nuclei of the cells of the glandular compartment of previtellogenic glands. We also have evidence of FMRFamide-like and cGnRH-I-like immunoreactivity in the nerve endings that reach the oviducal gland. Moreover, we have recently shown APGWamide immunoreactivity in the glandular cells of the inner part of the oviducal gland. Here we report a review on these findings as well as our latest studies on the effect that neuropeptides may exert on the secretory activity of the oviducal gland. cAMP seems to be a possible second messenger involved in such a process. We discuss the findings of a neuropeptidergic action on the glandular cells of oviducal gland in a more complex frame of molecules, such as steroids, biogenic amines and neuromodulators, controlling the activity of the gland.