Estrous cycle-dependent changes of Fas expression in the bovine corpus luteum: influence of keratin 8/18 intermediate filaments and cytokines

Prostaglandin F2 Alpha Triggers the Disruption of Cell Adhesion with Cytokeratin and Vimentin in Bovine Luteal Theca Cells

Simple Summary

Luteolysis is an important event in the control of the corpus luteum function in bovines. However, some aspects of the luteolytic mechanism remain unclear. We evaluated changes in cell adhesion in luteal cells during regression of corpus luteum. Bovine luteal theca cells (LTCs) were treated in vitro with Prostaglandin F2 alpha (PGF2α). Cytokeratin, vimentin and desmoplakin proteins in LTCs were disrupted by PGF2α, affecting cell adhesion. These results suggest that PGF2α plays an important function in cell adhesion during the regression of corpus luteum.

Abstract

Intermediate filaments (IFs) maintain cell–cell adhesions and are involved in diverse cellular processes such as cytokinesis, cell migration and the maintenance of cell structure. In this study, we investigated the influence of prostaglandin F2 alpha (PGF2α) on cytokeratin and vimentin IFs, Rho-associated protein kinase (ROCK), and cell-cell adhesion in bovine luteal theca cells (LTCs). The luteal cells were isolated from bovine corpus luteum (CL), and the LTCs were treated with 0, 0.01, 0.1 and 1.0 mM PGF2α. Cytokeratin, vimentin and desmoplakin proteins were disrupted and the ROCK protein was significantly increased in PGF2α-treated LTCs. In addition, cell–cell adhesion was significantly (p < 0.05) decreased in the PGF2α-induced LTCs compared to control group (0 mM PGF2α). In conclusion, PGF2α affected the adhesion of cell to cell via disruption of desmoplakin, cytokeratin and vimentin, additionally increasing ROCK in bovine LTCs. These results may provide a better understanding of the mechanism of bovine CL regression.

Insights into molecular pathways of endometriosis and endometriosis-related ovarian carcinoma

Background: Endometriosis is a benign estrogen-dependent gynecological disease involving components of the female genital tract (uterus, Fallopian tubes, ovaries, large, round, and utero-sacral ligaments) and intra- and extraperitoneal regions. Since the moment of its etiopathogeny has been identified, the intrinsic capacity of endometriosis malignant transformation has been hypothesized. Patients,Materials and Methods: Our study included a total number of 50 patients diagnosed with endometriosis (31 cases) and endometriosis-related ovarian carcinoma (EOC) (19 cases). A clinicopathological and immunohistochemical study directed towards the detection of atypical transition lesions and the similitudes in epithelial–mesenchymal transition (EMT) phenomenon [E-cadherin/β-catenin/cytokeratin 18 (CK18)], apoptosis [B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X (Bax)], and hormonal dynamics mirrored by the immunoexpression of estrogen receptor (ER) and progesterone receptor (PR) in endometriosis and EOC glands and stroma has been performed. Results: Our study showed a higher immunoexpression of CK18 and E-cadherin in endometriosis than in neoplastic counterparts, while β-catenin had a stronger immunoexpression in tumors compared with endometriotic areas, with statistically significant differences between the studied groups. Bcl-2/Bax higher rate in endometriosis had a statistically significant association to a more aggressive tumor behavior (p=0.020). ER immunoexpression was stronger in endometriosis, with less negative scores compared to EOC, while PR immunoexpression was stronger in endometriosis, with a lower percent of negative scores compared to EOC. PR immunostaining was correlated to ovarian location of endometriosis (p=0.004) and tumor grade of EOC (p=0.027). Stromal ER and PR immunoexpression has been significantly lower in endometriosis in comparison to tumor stroma (p=0.001) and PR stromal immunoexpression had been higher in more differentiated tumors compared to less differentiated types (p=0.005). Conclusions: Our study supports that endometriosis is a precursor of EOC by the identification and the coexistence of both lesions in the investigated cases, the identification of intermediate lesions, as well as the expression of EMT immunomarkers, along with apoptosis and steroid receptors immunoexpression.

Genotype-by-environment interaction in Holstein heifer fertility traits using single-step genomic reaction norm models

Background

The effect of heat stress on livestock production is a worldwide issue. Animal performance is influenced by exposure to harsh environmental conditions potentially causing genotype-by-environment interactions (G × E), especially in highproducing animals. In this context, the main objectives of this study were to (1) detect the time periods in which heifer fertility traits are more sensitive to the exposure to high environmental temperature and/or humidity, (2) investigate G × E due to heat stress in heifer fertility traits, and, (3) identify genomic regions associated with heifer fertility and heat tolerance in Holstein cattle.

Results

Phenotypic records for three heifer fertility traits (i.e., age at first calving, interval from first to last service, and conception rate at the first service) were collected, from 2005 to 2018, for 56,998 Holstein heifers raised in 15 herds in the Beijing area (China). By integrating environmental data, including hourly air temperature and relative humidity, the critical periods in which the heifers are more sensitive to heat stress were located in more than 30 days before the first service for age at first calving and interval from first to last service, or 10 days before and less than 60 days after the first service for conception rate. Using reaction norm models, significant G × E was detected for all three traits regarding both environmental gradients, proportion of days exceeding heat threshold, and minimum temperature-humidity index. Through single-step genome-wide association studies, PLAG1, AMHR2, SP1, KRT8, KRT18, MLH1, and EOMES were suggested as candidate genes for heifer fertility. The genes HCRTR1, AGRP, PC, and GUCY1B1 are strong candidates for association with heat tolerance.

Conclusions

The critical periods in which the reproductive performance of heifers is more sensitive to heat stress are trait-dependent. Thus, detailed analysis should be conducted to determine this particular period for other fertility traits. The considerable magnitude of G × E and sire re-ranking indicates the necessity to consider G × E in dairy cattle breeding schemes. This will enable selection of more heat-tolerant animals with high reproductive efficiency under harsh climatic conditions. Lastly, the candidate genes identified to be linked with response to heat stress provide a better understanding of the underlying biological mechanisms of heat tolerance in dairy cattle.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07496-3.

Global Transcriptomic Analysis of the Canine corpus luteum (CL) During the First Half of Diestrus and Changes Induced by in vivo Inhibition of Prostaglandin Synthase 2 (PTGS2/COX2)

The canine luteal phase exhibits several peculiarities compared with other species. In early diestrus, the corpus luteum (CL) is, at least in part, independent of gonadotropins, and prostaglandins (PGs) appear to be among its main regulators. This was also observed with the inhibition in vivo of COX2, when also transcriptional capacity, vascularization and immune-related factors were affected. Here, we aimed to further investigate the potential effects of PGs withdrawal on the CL transcriptome by performing deep RNA sequencing (RNA-Seq). Samples from a previous in vivo study were used; bitches were treated for 5, 10, 20, or 30 days after ovulation with firocoxib (Previcox®), a PTGS2/COX2 inhibitor, or a placebo. Analysis of results was performed with SUSHI (framework from FGCZ) and with pathways and functional networks analyzers. Time-dependent effects were also investigated and used for quality control. More highly represented differentially expressed genes (DEGs, P < 0.01, FDR < 0.1) in the early CL (days 5 and 10) referred to proliferation and immune system, while in the mature CL (days 20 and 30) they were related with steroidogenesis. The absence of genes concomitantly affected by the treatment at all time-points suggested stage-dependency in the observed effects. Little effect was observed on days 5 and 10. Day 20 had the highest number of DEGs (n = 1,741), related with increased immune response. On day 30, DEGs found (n = 552) referred to decreased steroidogenesis and vascularization. Our results suggest the presence of strong compensatory effects in the early CL and multidirectional effects toward gonadotropin-dependency of the CL after COX2 inhibition.

The Study on Biological Function of Keratin 26, a Novel Member of Liaoning Cashmere Goat Keratin Gene Family

In our research, we explored the relationship between Keratin 26 and the regulation of fine hair, BMP signaling pathway, MT, FGF5, and IGF-I. The result of hybridization in situ revealed that Keratin 26 was specially expressed in cortex of skin hair follicles; the result of immunohistochemistry indicated that Keratin 26 was expressed in internal root sheath, external root sheath. Then, Real-time quantitative PCR results showed that relative expressive quantity of Keratin 26 was 1.08 or 3.3 × greater in secondary follicle than primary follicle during anagen or catagen; the difference during anagen was not remarkable (p>0.05), however, that of catagen was extremely significant (p<0.01). Relative expressive quantity of Keratin 26 increased during telogen; the difference was extremely significant (p<0.01). Moreover, after Noggin expression interference using RNAi technology, we found that relative expressive quantity of Keratin 26 extremely remarkably declined (p<0.01); after K26 overexpression, we found that relative expressive quantity of Noggin extremely remarkably increased (p<0.01). We detected expressive quantity change of Keratin 26 and Keratin 26 using Real-time quantitative PCR and immunofluorescence technologies after fibroblasts were treated with MT, FGF5 or IGF-I; the results indicated that MT and FGF5 played a positive role in Keratin 26 and Keratin 26 expression, IGF-I played a negative role in Keratin 26 expression, positive role in Keratin 26 expression. The results above showed that Keratin 26 could inhibit cashmere growth, and was related to entering to catagen and telogen of hair follicles; Keratin 26 and BMP signaling pathway were two antagonistic pathways each other which could inhibit growth and development of cashmere; MT, FGF5 and IGF-I could affect expression of Keratin 26 and Keratin 26, and Keratin 26 was one of the important pathways that MT induced cashmere production in advance, FGF5 regulated cashmere growth and IGF-I promoted cashmere growth and development.

Cooperation of PD-1 and LAG-3 Contributes to T-Cell Exhaustion in Anaplasma marginale-Infected Cattle

The CD4(+) T-cell response is central for the control of Anaplasma marginale infection in cattle. However, the infection induces a functional exhaustion of antigen-specific CD4(+) T cells in cattle immunized with A. marginale outer membrane proteins or purified outer membranes (OMs), which presumably facilitates the persistence of this rickettsia. In the present study, we hypothesize that T-cell exhaustion following infection is induced by the upregulation of immunoinhibitory receptors on T cells, such as programmed death 1 (PD-1) and lymphocyte activation gene 3 (LAG-3). OM-specific T-cell responses and the kinetics of PD-1-positive (PD-1(+)) LAG-3(+) exhausted T cells were monitored in A. marginale-challenged cattle previously immunized with OMs. Consistent with data from previous studies, OM-specific proliferation of peripheral blood mononuclear cells (PBMCs) and interferon gamma (IFN-γ) production were significantly suppressed in challenged animals by 5 weeks postinfection (wpi). In addition, bacteremia and anemia also peaked in these animals at 5 wpi. Flow cytometric analysis revealed that the percentage of PD-1(+) LAG-3(+) T cells in the CD4(+), CD8(+), and γδ T-cell populations gradually increased and also peaked at 5 wpi. A large increase in the percentage of LAG-3(+) γδ T cells was also observed. Importantly, in vitro, the combined blockade of the PD-1 and LAG-3 pathways partially restored OM-specific PBMC proliferation and IFN-γ production at 5 wpi. Taken together, these results indicate that coexpression of PD-1 and LAG-3 on T cells contributes to the rapid exhaustion of A. marginale-specific T cells following infection and that these immunoinhibitory receptors regulate T-cell responses during bovine anaplasmosis.

Human umbilical cord blood-mesenchymal stem cells transplantation renovates the ovarian surface epithelium in a rat model of premature ovarian failure: Possible direct and indirect effects

This study aimed to isolate mesenchymal stem cells (MSC) from human umbilical cord blood (HCB) and to explore their influence on the ovarian epithelium after paclitaxel-induced ovarian failure. Ninety-five rats were divided into 6 groups: control, paclitaxel, paclitaxel and saline, HCB-MSC-treated for 2 weeks, HCB-MSC-treated for 4 weeks, and HCB-MSC-treated for 6 weeks. HCB cells were studied for CD34, CD44, and Oct ¾ using flow cytometry. Serum levels of FSH and E2 were measured using ELISA, RT-PCR analysis for human gene; beta-actin (ACTB), immunohistochemical analysis for CK 8/18, TGF-ß, PCNA and CASP-3 were performed. We found that ACTB gene was expressed in all rats' ovaries received HCB-MSC. After 4 weeks of transplantation, there was significant reduction in FSH, elevation in E2 levels, stabilization of the surface epithelium morphostasis, an increase in the antral follicle count and increase in integrated densities (ID) of CK 8/18, TGF-ß, and PCNA expressions and decrease in ID of CASP-3 expression. We concluded that HCB-MSC can restore the ovarian function after paclitaxel injection through a direct triggering effect on the ovarian epithelium and/or indirect enrichment of ovarian niche through regulating tissue expression of CK 8/18, TGF-ß and PCNA. These molecules are crucial in regulating folliculogenesis and suppressing CASP-3-induced apoptosis.

Molecular manipulation of keratin 8/18 intermediate filaments: modulators of FAS-mediated death signaling in human ovarian granulosa tumor cells

Background

Granulosa cell tumors (GCT) are a rare ovarian neoplasm but prognosis is poor following recurrence. Keratin intermediate filaments expressed in these tumors are a diagnostic marker, yet paradoxically, may also constitute a target for therapeutic intervention. In the current study, we evaluated keratin 8/18 (K8/18) filament expression as a mechanism of resistance to apoptosis in GCT, specifically focusing on regulation of the cell surface death receptor, Fas (FAS).

Methods

The GCT cell line, KGN, was transiently transfected with siRNA to KRT8 and KRT18 to reduce K8/18 filament expression. Expression of K8/18, FAS, and apoptotic proteins (PARP, cleaved PARP) were evaluated by fluorescence microscopy, flow cytometric analysis, and immunoblotting, respectively. The incidence of FAS-mediated apoptosis in KGN cells was measured by caspase 3/7 activity. All experiments were performed independently three to six times, using a fresh aliquot of KGN cells for each experiment. Quantitative data were analyzed by one- or two-way analysis of variance (ANOVA), followed by a Tukey’s post-test for multiple comparisons; differences among means were considered statistically significant at P < 0.05.

Results

Control cultures of KGN cells exhibited abundant K8/18 filament expression (~90 % of cells), and minimal expression of FAS (<25 % of cells). These cells were resistant to FAS-activating antibody (FasAb)-induced apoptosis, as determined by detection of cleaved PARP and measurement of caspase 3/7 activity. Conversely, siRNA-mediated knock-down of K8/18 filament expression enhanced FAS expression (> 70 % of cells) and facilitated FasAb-induced apoptosis, evident by increased caspase 3/7 activity (P < 0.05). Additional experiments revealed that inhibition of protein synthesis, but not MEK1/2 or PI3K signaling, also prompted FasAb-induced apoptosis.

Conclusions

The results demonstrated that K8/18 filaments provide resistance to apoptosis in GCT by impairing FAS expression. The abundance of keratin filaments in these cells and their role in apoptotic resistance provides a greater mechanistic understanding of ovarian tumorgenicity, specifically GCT, as well as a clinically-relevant target for potential therapeutic intervention.

Apoptosis-Related Factors in the Luteal Phase of the Domestic Cat and Their Involvement in the Persistence of Corpora Lutea in Lynx

The corpus luteum (CL) is a transient gland formed in the ovary after ovulation and is the major source of progesterone. In the Iberian and Eurasian lynx, CL physiologically persist after parturition and retain their capacity to produce progesterone, thus suppressing the ovarian activity. This unique reproductive characteristic has a big impact on the success of assisted reproduction techniques in the endangered Iberian lynx. The mechanisms behind CL persistence are not yet understood and require extensive studies on potential luteotropic and luteolytic factors in felids. Because the apoptosis system has been shown to be involved in structural regression of CL in many species, we aimed to investigate the capacity of perCL to undergo apoptosis. In addition, we performed initial studies on the apoptosis system in the luteal phase of the domestic cat. No previous research on this system has been made in this species. Our factors of interest included agents of the intrinsic apoptosis pathway, i.e., pro-survival B-cell CLL/lymphoma 2 (BCL2) and pro-apoptotic BCL2-associated X protein (BAX), the executioner caspase-3 (CASP3), as well as of the extrinsic pathway, i.e., pro-apoptotic receptor FAS, and tumor necrosis factor (TNF) and its receptors (pro-apoptotic TNFRSF1A and pro-survival TNFRSF1B). We analyzed the relative mRNA levels of these factors, as well as protein localization of CASP3 and TNF during stages of pregnancy and the non-pregnant luteal phase in CL of domestic cats. The same factors were investigated in freshly ovulated CL (frCL) and perCL of Iberian and Eurasian lynx, which were histologically analyzed. All factors were present in the CL tissue of both domestic cat and lynx throughout all analyzed stages. The presence of pro-apoptotic factors BAX, CASP3, FAS and TNFRSF1A in perCL of the Eurasian and Iberian lynx might indicate the potential sensitivity of perCL to apoptotic signals. The expression of pro-survival factors BCL2 and TNFRSF1B was significantly higher in perCL compared to frCL of studied Iberian lynx, suggesting the potential involvement of these factors in the structural integrity of perCL. In both Iberian lynx and pregnant and non-pregnant domestic cats, the expression of TNFRSF1A was significantly higher in forming CL compared to other stages, suggesting the conserved involvement of this factor in the tissue reorganization during formation of the feline CL. The mRNA levels of CASP3 and TNFRSF1B were highest during regression stages of domestic cat CL. The current study provides initial results on the possible involvement of the apoptosis system in the structure and function of the feline CL and in its physiological persistence.