Thrombospondin-1 inhibits angiogenesis and promotes follicular atresia in a novel in vitro angiogenesis assay

Endothelial PDGF-D contributes to neurovascular protection after ischemic stroke by rescuing pericyte functions

Ischemic stroke induces neovascularization of the injured tissue as an attempt to promote structural repair and neurological recovery. Angiogenesis is regulated by pericytes that potently react to ischemic stroke stressors, ranging from death to dysfunction. Platelet-derived growth factor (PDGF) receptor (PDGFR)β controls pericyte survival, migration, and interaction with brain endothelial cells. PDGF-D a specific ligand of PDGFRβ is expressed in the brain, yet its regulation and role in ischemic stroke pathobiology remains unexplored. Using experimental ischemic stroke mouse model, we found that PDGF-D is transiently induced in brain endothelial cells at the injury site in the subacute phase. To investigate the biological significance of PDGF-D post-ischemic stroke regulation, its subacute expression was either downregulated using siRNA or upregulated using an active recombinant form. Attenuation of PDGF-D subacute induction exacerbates neuronal loss, impairs microvascular density, alters vascular permeability, and increases microvascular stalling. Increasing PDGF-D subacute bioavailability rescues neuronal survival and improves neurological recovery. PDGF-D subacute enhanced bioavailability promotes stable neovascularization of the injured tissue and improves brain perfusion. Notably, PDGF-D enhanced bioavailability improves pericyte association with brain endothelial cells. Cell-based assays using human brain pericyte and brain endothelial cells exposed to ischemia-like conditions were applied to investigate the underlying mechanisms. PDGF-D stimulation attenuates pericyte loss and fibrotic transition, while increasing the secretion of pro-angiogenic and vascular protective factors. Moreover, PDGF-D stimulates pericyte migration required for optimal endothelial coverage and promotes angiogenesis. Our study unravels new insights into PDGF-D contribution to neurovascular protection after ischemic stroke by rescuing the functions of pericytes.

Duocarmycin SA Reduces Proliferation and Increases Apoptosis in Acute Myeloid Leukemia Cells In Vitro

Acute myeloid leukemia (AML) is a hematological malignancy that is characterized by an expansion of immature myeloid precursors. Despite therapeutic advances, the prognosis of AML patients remains poor and there is a need for the evaluation of promising therapeutic candidates to treat the disease. The objective of this study was to evaluate the efficacy of duocarmycin Stable A (DSA) in AML cells in vitro. We hypothesized that DSA would induce DNA damage in the form of DNA double-strand breaks (DSBs) and exert cytotoxic effects on AML cells within the picomolar range. Human AML cell lines Molm-14 and HL-60 were used to perform 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT), DNA DSBs, cell cycle, 5-ethynyl-2-deoxyuridine (EdU), colony formation unit (CFU), Annexin V, RNA sequencing and other assays described in this study. Our results showed that DSA induced DNA DSBs, induced cell cycle arrest at the G2M phase, reduced proliferation and increased apoptosis in AML cells. Additionally, RNA sequencing results showed that DSA regulates genes that are associated with cellular processes such as DNA repair, G2M checkpoint and apoptosis. These results suggest that DSA is efficacious in AML cells and is therefore a promising potential therapeutic candidate that can be further evaluated for the treatment of AML.

POI-associated EIF4ENIF1 mutations exhibit impaired translation regulation abilities

Various genetic variants have been found to be associated with the clinical onset of premature ovarian insufficiency (POI). However, when measured in vitro, the functional influence of the variants can be difficult to determine. By whole-exome sequencing (WES) of 93 patients with sporadic POI, we found a missense variant c.623G > A;p.R208H in the EIF4ENIF1 gene. In silico prediction of the variant using different algorithms suggested it might be a damaging variant. We compared the property of EIF4ENIF1 R208H and Q842P, a POI-related mutant that we reported previously, with wildtype (WT) protein using 293FT cells in vitro. Surprisingly, a change in subcellular distribution and granule forming ability (Q842P) and nuclear import capacity (R208H) was not observed, despite domain prediction evidences. Since EIF4ENIF1 was reported to inhibit translation, we employed T&T-seq, a translation-transcription dual-omics sequencing method, to profile gene expression upon overexpression of EIF4ENIF1 WT and mutants. EIF4ENIF1 WT overexpression group exhibited significantly (P < 0.0001) lower translation efficiency (TE) than empty vector or GFP overexpression control group. Surprisingly, EIF4ENIF1 Q842P overexpression failed to repress global translation, showing an overall TE significantly higher than WT group. Overexpression R208H significantly (P < 0.0001) lowered the overall TE, whereas exhibiting a reduced translation inhibitory effect on high-TE genes (TE > 2 in GFP control group). Several fertility-associated genes, such as AMH in Q842P group and SERPINE1 and THBS1 in R208H group, was translationally up-regulated in mutant groups versus WT control, suggesting a potential mechanism of mutated EIF4ENIF1 causing POI via impaired translation repression. It is further proposed that T&T-seq can be a sensitive evaluation tool for the measurement of functional alteration by variants in many other translational regulator genes, not only EIF4ENIF1, helping to eliminate misinterpretation of clinical significance of genetic variants.

Evaluation of the p53 pathway in polycystic ovarian syndrome pathogenesis and apoptosis enhancement in human granulosa cells through transcriptome data analysis

The polycystic ovarian syndrome (PCOS) is closely associated with enhanced apoptosis of granulosa cells, which have a vital role in maturation of oocytes. p53 plays a critical role in the regulation of apoptosis and cell cycle arrest, metabolism and insulin resistance. The aim of this study was to investigate the impact of p53 pathway in enhancing apoptosis and abnormal function of granulosa cells. In this study, microarray analysis and RNA sequencing were downloaded from the GEO and used as datasets. Principal Component Analysis (PCA) and online SSizer tool were applied to evaluate the experiment quality control and sample sufficiency, respectively. Bioinformatics' analyses were performed on the selected datasets, and validated by qRT-PCR and western blot analyses. Three datasets out of five ones were chosen for re-analyzing based on the PCA outcomes. 21 deregulated genes were identified via filters including p < 0.05 and |log2FC|≥ 1. Functional enrichment analysis confirmed the relevance of cell cycle regulation and apoptosis as common biological hallmarks in PCOS. Results have shown differentially expressed p53 target genes involved in apoptosis (BAX, FAS, PMAIP1, and CASP8), cell cycle (Cyclins, Cyclin dependent kinases), glucose metabolism and insulin resistance (THBS1), and p53 regulation (MDM2). Subsequently, the relative mRNA expression of FAS, PMAIP1 and MDM2 genes, and protein levels of p53 and MDM2 were confirmed using granulosa cells collected from 20 PCOS women and 18 control individuals by qRT-PCR and western blot, respectively. Results of this study represent the possible role of p53 pathway in pathogenesis of PCOS particularly, through the enhancement of apoptosis in granulosa cells.

Integrated transcriptome and proteome revealed that the declined expression of cell cycle-related genes associated with follicular atresia in geese

BACKGROUND

Geese exhibit relatively low reproductive performance, and follicular atresia is an important factor that restricts the egg production of geese. Systematic analysis of the regulation of follicle atresia in geese through transcriptome and proteome levels could provide meaningful information on clarifying the mechanism of follicle atresia in poultry.

RESULT

The granulosa cell layer was loose, disintegrated and showed apoptosis in atretic follicles and remained intact in normal follicles. The hormone levels of FSH and LH were significantly decreased in the atresia follicles compared to the normal follicles (P < 0.05). A total of 954 differentially expressed genes (DEGs, 315 increased and 639 decreased) and 161 differentially expressed proteins (DEPs, 61 increased and 100 decreased) were obtained in atresia follicles compared to normal follicles, of which, 15 genes were differentially expressed in both transcriptome and proteome. The DEGs were mainly enriched in sodium transmembrane transport, plasma membrane, and transmembrane transporter activity based on the GO enrichment analysis and in the cell cycle pathway based on the KEGG enrichment analysis. The DEPs were mainly enriched in localization, lysosome, and phospholipid-binding based on the GO enrichment analysis. Candidate genes Smad2/3, Smad4, Annexin A1 (ANXA1), Stromelysin-1 (MMP3), Serine/threonine-protein kinase (CHK1), DNA replication licensing factor (MCM3), Cyclin-A2 (CCNA2), mitotic spindle assembly checkpoint protein (MAD2), Cyclin-dependent kinase 1 (CDK1), fibroblast growth factor 12 (FGF12), and G1/S-specific cyclin-D1 (CCND1) were possibly responsible for the regulation of atresia.

CONCLUSION

The cell cycle is an important pathway for the regulation of follicular atresia. Sodium outflow and high expression of MMP3 and MMP9 could be responsible for structural destruction and apoptosis of follicular cells.

Hormone regulation of thrombospondin-1 mRNA in porcine granulosa cells in vitro

Thrombospondin-1 (THBS1) is involved in the process of angiogenesis and is down-regulated by insulin-like growth factor 1 (IGF1) in porcine granulosa cells (GC), but what other hormones regulate GC THBS1 and its role in follicular growth is unclear. Thus, six experiments were conducted to determine the influence of other hormones on THBS1 gene expression in porcine GC, and to determine if THBS1 mRNA changes during follicular development. For Exp. 1-5, small (1-5 mm) follicles from ovaries of abattoir gilts were aspirated, GC collected and treated with FSH, IGF1, fibroblast growth factor 9 (FGF9), Sonic hedgehog (SHH), estradiol, cortisol, and/or prostaglandin E2 (PGE2). FSH, IGF1 and FGF9 each decreased (P < 0.05) THBS1 mRNA abundance. Alone, PGE2 increased (P < 0.05) THBS1 mRNA abundance. PGE2 significantly attenuated the FSH-induced inhibition of THBS1 mRNA expression. Estradiol, cortisol, and SHH had no effect on THBS1 mRNA abundance. In Exp. 6, small (1-3 mm), medium (4-6 mm) and large (7-14 mm) follicles were aspirated to measure abundance of THBS1 mRNA in GC which did not differ (P > 0.10) between small and medium-sized follicles but was threefold greater (P < 0.05) in large compared to small or medium follicles. We hypothesize that the inhibitory effects of FSH, IGF1 and FGF9 on the antiangiogenic gene THBS1 could contribute to promoting angiogenesis in the developing follicle, while stimulation of THBS1 mRNA by PGE2 may help reduce angiogenesis during the preovulatory period when PGE2 and THBS1 mRNA are at their greatest levels.

Anti-Obesity Effect of Rice Bran Extract on High-Fat Diet-Induced Obese Mice

Obesity involving adipose tissue growth and development are associated with angiogenesis and extracellular matrix remodeling. Rice bran has antioxidant and cardioprotective properties, and can act as a food supplement with potential health benefits, such as lowering blood pressure, hepatic steatosis, and inflammation. Therefore, we hypothesized that rice bran extract (RBE) can regulate adipose tissue growth and obesity. Male Institute of Cancer Research mice were fed with a high-fat diet (HFD) for 8 weeks and then supplemented with 220 and 1,100 mg/kg/d RBE while the low-fat diet group (control) were not. In addition to body weight, adipose tissue mass, and vessel density, we evaluated the mRNA expression of angiogenic factors such as matrix metalloproteinases, Mmp-2, Mmp-9, and the vascular endothelial growth factor (Vegf) in visceral and subcutaneous adipose tissues using real-time polymerase chain reaction. Administration of RBE to HFD-induced obese mice reduced the body weight and adipose tissue mass compared with untreated mice. It also decreased blood vessel density in the adipose tissue. Furthermore, RBE downregulated Vegf and Mmp-2 mRNA levels in visceral fat tissue. These results demonstrate that RBE, at high concentrations, significantly reduces adipose tissue mass and prevents obesity development in HFD-induced obese mice, which might be partly mediated via an anti-angiogenic mechanism.

Delta-9-tetrahydrocannabinol increases vascular endothelial growth factor (VEGF) secretion through a cyclooxygenase-dependent mechanism in rat granulosa cells

While the effects of delta-9-tetrahydrocannabinol (THC), the psychoactive component of cannabis, have been studied extensively in the central nervous system, there is limited knowledge about its effects on the female reproductive system. The aim of this study was to assess the effect of THC on the expression and secretion of the angiogenic factor vascular endothelial growth factor (VEGF) in the ovary, and to determine if these effects were mediated by prostaglandins. Spontaneously immortalized rat granulosa cells (SIGCs) were exposed to THC for 24hours. Gene expression, proliferation and TNFα-induced apoptosis were evaluated in the cells and concentrations of VEGF and prostaglandin E2 (PGE₂), a known regulator of VEGF production, were determined in the media. To evaluate the role of the prostanoid pathway, cells were pre-treated with cyclooxygenase (COX) inhibitors prior to THC exposure. THC-exposed SIGCs had a significant increase in VEGF and PGE₂ secretion, along with an increase in proliferation and cell survival when challenged with an apoptosis-inducing factor. Pre-treatment with COX inhibitors reversed the THC-induced increase in both PGE₂ and VEGF secretion. Alterations in granulosa cell function, such as the ones observed after THC exposure, may impact essential ovarian processes including folliculogenesis and ovulation, which could in turn affect female reproductive health and fertility. With the ongoing increase in cannabis use and potency, further study on the impact of cannabis and its constituents on female reproductive health is required.

Transcriptomic analyses of the HPG axis-related tissues reveals potential candidate genes and regulatory pathways associated with egg production in ducks

Background

Egg production is one of the most important economic traits in the poultry industry. The hypothalamic-pituitary–gonadal (HPG) axis plays an essential role in regulating reproductive activities. However, the key genes and regulatory pathways within the HPG axis dominating egg production performance remain largely unknown in ducks.

Results

In this study, we compared the transcriptomic profiles of the HPG-related tissues between ducks with high egg production (HEP) and low egg production (LEP) to reveal candidate genes and regulatory pathways dominating egg production. We identified 543, 759, 670, and 181 differentially expressed genes (DEGs) in the hypothalamus, pituitary, ovary stroma, and F5 follicle membrane, respectively. Gene Ontology (GO) analysis revealed that DEGs from four HPG axis-related tissues were enriched in the "cellular component" category. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that the neuroactive ligand-receptor interaction pathway was significantly enriched based on DEGs commonly identified in all four HPG axis-related tissues. Gene expression profiles and Protein–Protein Interaction (PPI) network were performed to show the regulatory relationships of the DEGs identified. Five DEGs encoding secreted proteins in the hypothalamus and pituitary have interaction with DEGs encoding targeted proteins in the ovary stroma and F5 follicle membrane, implying that they were these DEGs might play similar roles in the regulation of egg production.

Conclusions

Our results revealed that neuroactive ligand-receptor interaction pathway and five key genes(VEGFC, SPARC, BMP2, THBS1, and ADAMTS15) were identified as the key signaling pathways and candidate genes within the HPG axis responsible for different egg production performance between HEP and LEP. This is the first study comparing the transcriptomic profiles of all HPG axis-related tissues in HEP and LEP using RNA-seq in ducks to the best of our knowledge. These data are helpful to enrich our understanding of the classical HPG axis regulating the egg production performance and identify candidate genes that can be used for genetic selection in ducks.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08483-y.

Transcriptome analysis reveals that long noncoding RNAs contribute to developmental differences between medium-sized ovarian follicles of Meishan and Duroc sows

Ovulation rate is an extremely important factor affecting litter size in sows. It differs greatly among pig breeds with different genetic backgrounds. Long non-coding RNAs (lncRNAs) can regulate follicle development, granulosa cell growth, and hormone secretion, which in turn can affect sow litter size. In this study, we identified 3554 lncRNAs and 25,491 mRNAs in M2 follicles of Meishan and Duroc sows. The lncRNA sequence and open reading frame lengths were shorter than mRNAs, and lncRNAs had fewer exons, were less abundant, and more conserved than protein-coding RNAs. Furthermore, 201 lncRNAs were differentially expressed (DE) between breeds, and quantitative trait loci analysis of DE lncRNAs were performed. A total of 127 DE lncRNAs were identified in 119 reproduction trait-related loci. In addition, the potential target genes of lncRNAs in cis or trans configurations were predicted. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that some potential target genes were involved in follicular development and hormone secretion-related biological processes or pathways, such as progesterone biosynthetic process, estrogen metabolic process, ovarian steroidogenesis, and PI3K-Akt signaling pathway. Furthermore, we also screened 19 differentially expressed lncRNAs in the PI3K-Akt signaling pathway as candidates. This study provides new insights into the roles of lncRNAs in follicular growth and development in pigs.

Pathways and factors regulated by bone marrow-derived stem cells in human ovarian tissue

OBJECTIVE

To describe molecular and paracrine signaling changes produced by human bone marrow-derived stem cells (BMDSC) in human ovarian cortex.

DESIGN

Experimental study.

SETTING

University hospital research laboratories.

PATIENT(S)

Ovarian cortex from poor responder women (n = 7).

ANIMALS

Immunodeficient NOD/SCID female mice (n = 18).

INTERVENTION(S)

Human ovarian cortex strips were xenografted into ovariectomized NOD/SCID female mice. A week later, mice were infused with phosphate-buffered saline, 1 × 106 BMDSC, or 3 × 105 CD133+ cells via tail vein. Gene expression changes and enriched pathways were assessed by RT2 Profiler Arrays. Several upregulated genes were validated in individual samples by real-time quantitative PCR, and transcriptomic results were reinforced by a proteomic assessment.

MAIN OUTCOME MEASURE(S)

Gene expression changes, enriched Kyoto Encyclopedia of Genes and Genomes pathways, and paracrine factors.

RESULT(S)

Seventy-four Kyoto Encyclopedia of Genes and Genomes pathways were upregulated, with the PI3K-Akt signaling pathway the most enriched after BMDSC and CD133 treatments. The greatest transcriptomic changes were seen on day 14 in the BMDSC group, affecting the regulation of paracrine factors such as KITLG, THBS1, SERPINF1, and TIMP2. Proteomics data verified changes in FoxO signaling, actin cytoskeleton remodeling, and apoptosis by BMDSC.

CONCLUSION(S)

We identified paracrine factors and pathways regulated by BMDSC that may be future targets of treatment for the increasing number of poor responder women. Our findings suggest that BMDSC upregulated soluble factors such as KITLG, THBS1, SERPINF1, and TIMP2 as well as PI3K-Akt signaling and regulation of actin cytoskeleton pathways. The identification of these putative underlying mechanisms informs future experiments aiming to optimizing clinical application of BMDSC.

Stem cell-secreted factor therapy regenerates the ovarian niche and rescues follicles

BACKGROUND

Ovarian senescence is a normal age-associated phenomenon, but increasingly younger women are affected by diminished ovarian reserves or premature ovarian insufficiency. There is an urgent need for developing therapies to improve ovarian function in these patients. In this context, previous studies suggest that stem cell-secreted factors could have regenerative properties in the ovaries.

OBJECTIVE

This study aimed to test the ability of various human plasma sources, enriched in stem cell-secreted factors, and the mechanisms behind their regenerative properties, to repair ovarian damage and to promote follicular development.

STUDY DESIGN

In the first phase, the effects of human plasma enriched in bone marrow stem cell soluble factors by granulocyte colony-stimulating factor mobilization, umbilical cord blood plasma, and their activated forms on ovarian niche, follicle development, and breeding performance were assessed in mouse models of chemotherapy-induced ovarian damage (n=7 per group). In addition, the proteomic profile of each plasma was analyzed to find putative proteins and mechanism involved in their regenerative properties in ovarian tissue. In the second phase, the most effective plasma treatment was validated in human ovarian cortex xenografted in immunodeficient mice (n=4 per group).

RESULTS

Infusion of human plasma enriched bone marrow stem cell soluble factors by granulocyte colony-stimulating factor mobilization or of umbilical cord blood plasma-induced varying degrees of microvessel formation and cell proliferation and reduced apoptosis in ovarian tissue to rescue follicular development and fertility in mouse models of ovarian damage. Plasma activation enhanced these effects. Activated granulocyte colony-stimulating factor plasma was the most potent inducing ovarian rescue in both mice and human ovaries, and proteomic analysis indicated that its effects may be mediated by soluble factors related to cell cycle and apoptosis, gene expression, signal transduction, cell communication, response to stress, and DNA repair of double-strand breaks, the most common form of age-induced damage in oocytes.

CONCLUSION

Our findings suggested that stem cell-secreted factors present in both granulocyte colony-stimulating factor-mobilized and umbilical cord blood plasma could be an effective treatment for increasing the reproductive outcomes in women with impaired ovarian function owing to several causes. The activated granulocyte colony-stimulating factor plasma, which is already enriched in both stem cell-secreted factors and platelet-enclosed growth factors, seems to be the most promising treatment because of its most potent restorative effects on the ovary together with the autologous source.

Human Granulosa Cells-Stemness Properties, Molecular Cross-Talk and Follicular Angiogenesis

The ovarian follicle is the basic functional unit of the ovary, comprising theca cells and granulosa cells (GCs). Two different types of GCs, mural GCs and cumulus cells (CCs), serve different functions during folliculogenesis. Mural GCs produce oestrogen during the follicular phase and progesterone after ovulation, while CCs surround the oocyte tightly and form the cumulus oophurus and corona radiata inner cell layer. CCs are also engaged in bi-directional metabolite exchange with the oocyte, as they form gap-junctions, which are crucial for both the oocyte’s proper maturation and GC proliferation. However, the function of both GCs and CCs is dependent on proper follicular angiogenesis. Aside from participating in complex molecular interplay with the oocyte, the ovarian follicular cells exhibit stem-like properties, characteristic of mesenchymal stem cells (MSCs). Both GCs and CCs remain under the influence of various miRNAs, and some of them may contribute to polycystic ovary syndrome (PCOS) or premature ovarian insufficiency (POI) occurrence. Considering increasing female fertility problems worldwide, it is of interest to develop new strategies enhancing assisted reproductive techniques. Therefore, it is important to carefully consider GCs as ovarian stem cells in terms of the cellular features and molecular pathways involved in their development and interactions as well as outline their possible application in translational medicine.

Microvascularization and Expression of Fibroblast Growth Factor and Vascular Endothelial Growth Factor and Their Receptors in the Mare Oviduct

Simple Summary

The oviduct provides the ideal conditions for fertilization and early embryonic development. Adequate vascularization is essential for proper oviduct physiological function. In this work on the mare oviduct, differences in the oviductal artery and arterioles and their ramifications in the infundibulum, ampulla and isthmus were examined. Locally, vascularization is modulated by the action of angiogenic factors, mediated by their specific receptors. In the present study, the isthmus presented the largest vascular area and the highest number of vascular structures in the follicular phase. We have also shown that the relative abundance of angiogenic transcripts and proteins, such as fibroblast growth factor 1 (FGF1) and 2 (FGF2) and vascular endothelial growth factor (VEGF), and their respective receptors (FGFR1, FGFR2, VEGFR2 = KDR), were present in all portions of the oviduct throughout the estrous cycle. There was an increase in the transcripts of angiogenic receptors FGF1 and FGFR1 in the ampulla and isthmus, and of FGF2 and KDR in the isthmus. This was also observed in the isthmus, where the relative abundance of proteins FGFR1 and KDR was the highest. This study shows that the equine oviduct presents differences in microvascular density in its portions. The angiogenic factors VEGF, FGF1, FGF2 and their respective receptors are expressed in all studied regions of the mare oviduct, in agreement with microvascular patterns.

Abstract

The oviduct presents the ideal conditions for fertilization and early embryonic development. In this study, (i) vascularization pattern; (ii) microvascular density; (iii) transcripts of angiogenic factors (FGF1, FGF2, VEGF) and their receptors—FGFR1, FGFR2, KDR, respectively, and (iv) the relative protein abundance of those receptors were assessed in cyclic mares’ oviducts. The oviductal artery, arterioles and their ramifications, viewed by means of vascular injection-corrosion, differed in the infundibulum, ampulla and isthmus. The isthmus, immunostained with CD31, presented the largest vascular area and the highest number of vascular structures in the follicular phase. Transcripts (qPCR) and relative protein abundance (Western blot) of angiogenic factors fibroblast growth factor 1 (FGF1) and 2 (FGF2) and vascular endothelial growth factor (VEGF), and their respective receptors (FGFR1, FGFR2, VEGFR2 = KDR), were present in all oviduct portions throughout the estrous cycle. Upregulation of the transcripts of angiogenic receptors FGF1 and FGFR1 in the ampulla and isthmus and of FGF2 and KDR in the isthmus were noted. Furthermore, in the isthmus, the relative protein abundance of FGFR1 and KDR was the highest. This study shows that the equine oviduct presents differences in microvascular density in its three portions. The angiogenic factors VEGF, FGF1, FGF2 and their respective receptors are expressed in all studied regions of the mare oviduct, in agreement with microvascular patterns.

Exposure to Benzo[a]pyrene impairs the corpus luteum vascular network in rats during early pregnancy

Benzo [a]pyrene (BaP) is a well-known endocrine disruptor. Exposure to BaP is known to impair embryo implantation. The corpus luteum (CL), the primary source of progesterone during early pregnancy, plays a pivotal role in embryo implantation and pregnancy maintenance. The inappropriate luteal function may result in implantation failure and spontaneous abortions. However, the effect of BaP on CL remains unknown. This study investigated the deleterious effects of BaP on the structure and function of CL during early pregnancy. Pregnant rats were dosed with BaP at 0.2 mg.kg-1. d from day 1 (D1) to day 9 (D9) of gestation. We found that BaP reduced the number of CLs, disturbed the secretion of steroid and impacted the luteal vascular networks. BaP significantly decreased the angiogenesis factor (VEGFR, Ang-1 and Tie2) and increased the anti-angiogenic factor THBS1. Inhibited THBS1 function by LSKL partially rescued the angiogenesis defect caused by BaP. In vitro, BaP metabolite BPDE also interfered the expression levels of angiogenesis-related factors in HUVECs and impaired the angiogenesis, whereas supplemented with rAng-1 can alleviate the anti-angiogenic effect of BPDE. Furthermore, Notch signaling molecules, including Notch1, Dll4, Jag1 and Hey2, which are essential for the establishment and maturation of vascular networks, were affected by BaP exposure. Collectively, BaP broke the molecular regulatory balance between luteal angiogenesis and vascular maturation, impaired the construction of luteal vascular networks, and further affected luteal formation and endocrine function during early pregnancy. Our findings might provide new insight into the relationship between BaP and luteal insufficiency in early pregnancy. These data also give a new line of evidence for curtailing BaP emissions and protecting the women of childbearing age from occupational exposure.

mRNA and miRNA Transcriptome Profiling of Granulosa and Theca Layers From Geese Ovarian Follicles Reveals the Crucial Pathways and Interaction Networks for Regulation of Follicle Selection

Follicle development is characterized by the recruitment, growth, selection, and dominance of follicles, and follicle selection determines the lifetime reproductive performance. However, in birds, the molecular mechanisms underlying follicle selection still remain elusive. This study analyzed genome-wide changes in the mRNA and miRNA expression profiles in both the granulosa and theca layers of geese ovarian follicles before selection (4–6- and 8–10-mm follicles) and after selection (F5). The sequencing results showed that a higher number of both differentially expressed (DE) mRNAs and DE miRNAs were identified between 8–10-mm and F5 follicles compared with those between the 4–6- and 8–10-mm follicles, especially in the granulosa layer. Moreover, a Short Time-series Expression Miner analysis identified a large number of DE mRNAs and DE miRNAs that are associated with follicle selection. The functional enrichment analysis showed that DE genes in the granulosa layer during follicle selection were mainly enriched in five pathways related to junctional adhesion and two pathways associated with lipid metabolism. Additionally, an interaction network was constructed to visualize interactions among protein-coding genes, which identified 53 junctional adhesion- and 15 lipid regulation-related protein-coding genes. Then, a co-expression network between mRNAs and miRNAs in relation to junctional adhesion was also visualized and mainly included acy-miR-2954, acy-miR-218, acy-miR-2970, acy-miR-100, acy-miR-1329, acy-miR-199, acy-miR-425, acy-miR-181, and acy-miR-147. Furthermore, miRNA–mRNA interaction pairs related to lipid regulation were constructed including acy-miR-107, acy-miR-138, acy-miR-130, acy-miR-128, and acy-miR-101 during follicular selection. In summary, these data highlight the key roles of junctional adhesion and lipid metabolism during follicular selection and contribute to a better understanding of the mechanisms underlying follicle selection in birds.

MiR-222 inhibits apoptosis in porcine follicular granulosa cells by targeting the THBS1 gene

Apoptosis of granulosa cells affects follicular atresia and reproduction and is regulated by miRNAs and the expression of certain genes. For the present study, we investigated the regulatory relationship between microRNA-222 (miR-222) and THBS1 in porcine follicular granulosa cells (pGCs) and its effects on apoptosis to provide empirical data for developing methods to improve pig fecundity. Results revealed that miR-222 promotes the proliferation of pGCs. MiRNA mimics and luciferase reporter assays revealed that miR-222 functions as an anti-apoptotic factor in pGCs. MiR-222 mimics in pGCs result in the upregulation of the anti-apoptotic BCL-2 gene, down-regulation of the proapoptotic caspase-3 gene, and inhibition of apoptosis. MiR-222 inhibitors reduced BCL-2 and had no significant effect on caspase-3. MiR-222 mimics promoted estrogen levels. Inhibition of THBS1 inhibited pGC apoptosis. Transfection of THBS1-siRNA reduced the proapoptotic BAX gene. MiR-222 can directly target the 3'-untranslated region of the THBS1 gene. MiR-222 mimics suppressed THBS1 mRNA and proteins, but these were upregulated by the miR-222 inhibitor. Transfection of THBS1-siRNA resulted in the inhibition of the miR-222 inhibitor, which suggests that miR-222 inhibits pGC apoptosis by targeting THBS1. These findings suggest that miR-222 and THBS1 play important roles in follicular atresia, ovarian development, and female reproduction.

Regulation of steroidogenic function of luteal cells by thrombospondin and insulin in water buffalo (Bubalus bubalis)

The present study examined the effect of exogenous thrombospondin 1 (TSP1) on the steroidogenic function of luteal cells cultured invitro. Furthermore, the transcriptional interaction of insulin with TSP1 and its receptor, cluster of differentiation 36 (CD36) were also investigated. At the highest dose (500ngmL−1) TSP1 significantly downregulated the expression of the angiogenic marker von Willebrand factor (vWF) and progesterone production in cultured luteal cells. Moreover, the simultaneous upregulation in the expression of caspase 3 by exogenous TSP1 was consistent with a reduction in the number of viable luteal cells as determined by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltertrazolium bromide (MTT) assay after 72h of culture. However, the expression of critical enzymes in the progesterone synthetic pathway was not significantly modulated by treatment with TSP1 in cultured luteal cells. Knocking out of endogenous TSP1 with the clustered regularly interspaced short palindromic repeats (CRISPR)/ CRISPRassociated protein9 (Cas9) system improved the viability of luteal cells as well as increasing progesterone production and decreasing caspase 3 activation. Insulin treatment suppressed the expression of TSP1 and CD36 in cultured luteal cells in a dose- and time-dependent manner. To conclude, TSP1 acts as a negative endogenous regulator of angiogenesis that attenuates progesterone production, possibly by reducing the number of luteal cells via apoptosis during luteal regression, whereas insulin as a luteinising signal may have inhibited the thrombospondin system for the efficient development of luteal function.

Autologous stem cell ovarian transplantation to increase reproductive potential in patients who are poor responders

OBJECTIVE

To evaluate effects of autologous stem cell ovarian transplant (ASCOT) on ovarian reserve and IVF outcomes of women who are poor responders with very poor prognosis.

DESIGN

Prospective observational pilot study.

SETTING

University hospital.

PATIENT(S)

Seventeen women who are poor responders.

INTERVENTION(S)

Ovarian infusion of bone marrow-derived stem cells.

MAIN OUTCOME MEASURE(S)

Serum antimüllerian hormone levels and antral follicular count (AFC), punctured follicles, and oocytes retrieved after stimulation (controlled ovarian stimulation) were measred. Apheresis was analyzed for growth factor concentrations.

RESULT(S)

The ASCOT resulted in a significant improvement in AFC 2 weeks after treatment. With an increase in AFC of three or more follicles and/or two consecutive increases in antimüllerian hormone levels as success criteria, ovarian function improved in 81.3% of women. These positive effects were associated with the presence of fibroblast growth factor-2 and thrombospondin. During controlled ovarian stimulation, ASCOT increased the number of stimulable antral follicles and oocytes, but the embryo euploidy rate was low (16.1%). Five pregnancies were achieved: two after ET, three by natural conception.

CONCLUSION(S)

Our results suggest that ASCOT optimized the mobilization and growth of existing follicles, possibly related to fibroblast growth factor-2 and thrombospondin-1 within apheresis. The ASCOT improved follicle and oocyte quantity enabling pregnancy in women who are poor responders previously limited to oocyte donation.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02240342.

Melatonin protects against cisplatin-induced ovarian damage in mice via the MT1 receptor and antioxidant activity

This study evaluated the receptor- and/or antioxidant stress-mediated mechanisms by which melatonin prevents the ovarian toxicity of cisplatin treatment. The expression of the MT1 receptor in mouse ovaries was investigated by immunohistochemistry. Pretreatment with melatonin (5, 10, or 20 mg/kg body weight, i.p.) before cisplatin (5 mg/kg body weight, i.p.) was administered to mice once daily for 3 days (phase I). The pharmacological modulation via melatonin type 1 and/or 2 receptors was analyzed by administration of receptor antagonists (luzindole: nonselective MT1/MT2 antagonist; 5 mg/kg body weight or 4-phenyl-2-propionamidotetralin: selective MT2 antagonist; 4 mg/kg body weight) once daily for 3 days, 15 min before the treatment with melatonin and cisplatin (phase II). Thereafter, the ovaries were harvested and used for histological (morphology and activation), immunohistochemical (PCNA, activated caspase-3 and bcl-2 expression), terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling, and fluorescence (reactive oxygen species [ROS], glutathione [GSH], and active mitochondria levels) analyses. The expression of the MT1 protein in mouse ovaries was documented. Pretreatment with 20 mg/kg melatonin before cisplatin administration preserved the normal follicular morphology and cell proliferation rate, reduced apoptosis, ROS production, mitochondrial damage and increased GSH expression, as compared to the cisplatin treatment alone. Additionally, administration of the nonselective MT1/MT2 receptor antagonist inhibited the melatonin ovarian protection from the cytotoxic effects of cisplatin. However, administration of a selective MT2 antagonist did not modify the protective effects observed at 20 mg/kg melatonin. In conclusion, pretreatment with 20 mg/kg melatonin effectively protected the ovaries against cisplatin-induced damage. Moreover, the MT1 receptor and melatonin antioxidant effects mediated this cytoprotective activity.

Localization of thrombospondin-1 and its receptor CD36 in the ovary of the ostrich (Struthio camelus)

Angiogenesis, the formation of new blood vessels from pre-existing vasculature, plays a decisive role for the rapid growth of avian follicles. Compared to mammals, few data on the angiogenesis in the avian ovary are available. However, whereas several pro-angiogenic factors in the avian ovary have been recently studied in detail, little information is available on the localization of anti-angiogenic factors. The aim of this study was to determine the localization and possible function of the anti-angiogenic factor thrombospondin-1 (TSP-1) and its receptor CD36 in the ovary of the ostrich using immunohistochemistry and to correlate the results with ultrastructural data. Whereas the oocytes and granulosa cells of all follicular stages were negative for TSP-1, myofibroblasts of the theca externa and smooth muscle cells of blood vessels showed distinct reactions. A distinctly different staining pattern was observed for CD36. The oocytes were CD36 negative. No immunostaining for CD36 could be observed neither in the granulosa cells nor in the adjacent theca interna of vitellogenic follicles. In the theca externa, blood vessels protruding towards the oocyte showed CD36-positive endothelial cells. In conclusion, a fine balance between angiogenic and anti-angiogenic processes assures that a dense net of blood vessels develops during the rapid growth of a selected follicle. Anti-angiogenic molecules, such as TSP-1 and its receptor CD36 may, after the oocyte has reached its final size, inhibit further angiogenesis and limit the transport of yolk material to the mature oocyte. By this mechanism, the growth of the megalecithal oocyte during folliculogenesis may cease.

Transcriptional profiling of porcine granulosa cells exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a toxic man-made chemical compound contaminating the environment. An exposure of living organisms to TCDD may result in numerous disorders, including reproductive pathologies. The aim of the current study was to examine the effects of TCDD on the transcriptome of porcine granulosa cell line AVG-16. By employing next-generation sequencing (NGS) we aimed to identify genes potentially involved in the mechanism of TCDD action and toxicity in porcine granulosa cells. The AVG-16 cells were treated with TCDD (100 nM) for 3, 12 or 24 h, and afterwards total cellular RNA was isolated and sequenced. In TCDD-treated cells we identified 141 differentially expressed genes (DEGs; p_adjusted < 0.05 and log2 fold change ≥1.0). The DEGs were assigned to GO term, covering biological processes, molecular functions and cellular components. Due to the large number of genes with altered expression, in the current study we analyzed only the genes involved in follicular growth, development and functioning. The obtained results showed that TCDD may affect ovarian follicle fate by influencing granulosa cell cycle, proliferation and DNA repair. The demonstrated over-time changes in the quantity and quality of genes being affected by TCDD treatment showed that the effects of TCDD on granulosa cells changed dramatically between 3-, 12- and 24-h of cell culture. This finding indicate that timing of gene expression measurement is critical for drawing correct conclusions on detailed relationships between the TCDD-affected genes and resulting intracellular processes. These conclusions have to be confirmed and extended by research involving proteomic and functional studies.

Expression and localization of members of the thrombospondin family during final follicle maturation and corpus luteum formation and function in the bovine ovary

The aim of this study was to characterize the expression patterns and localization of the thrombospondin family members (THBS1, THBS2) and their receptors (CD36 and CD47) in bovine ovaries. First, the antral follicles were classified into 5 groups based on the follicle size and estradiol-17beta (E2) concentration in the follicular fluid (< 0.5, 0.5-5, 5-40, 40-180 and >180 E2 ng/ml). Second, the corpus luteum (CL) was assigned to the following stages: days 1-2, 3-4, 5-7, 8-12, 13-16 and >18 of the estrous cycle and of pregnancy (month 1-2, 3-4, 6-7 and > 8). Third, the corpora lutea were collected by transvaginal ovariectomy before and 0.5, 2, 4, 12, 24, 48 and 64 h after inducing luteolysis by injecting a prostaglandin F2alpha analog. The mRNA expression of examined factors was measured by RT-qPCR, steroid hormone concentration by EIA, and localization by immunohistochemistry. The mRNA expression of THBS1, THBS2, CD36, and CD47 in the granulosa cells and theca interna was high in the small follicles and reduced in the preovulatory follicles. The mRNA expression of THBS1, THBS2, and CD47 in the CL during the estrous cycle was high, but decreased significantly during pregnancy. After induced luteolysis, thrombospondins increased significantly to reach the maximum level at 12 h for THBS1, 24 h for THBS2, and 48 h for CD36. The temporal expression and localization pattern of the thrombospondins and their specific receptors in the antral follicles and corpora lutea during the different physiological phases of the estrous cycle and induced luteolysis appear to be compatible with their inhibitory role in the control of ovarian angiogenesis.

Pterostilbene carboxaldehyde thiosemicarbazone, a resveratrol derivative inhibits 17β-Estradiol induced cell migration and proliferation in HUVECs

Angiogenesis plays important roles in tumor growth and metastasis, thus development of a novel angiogenesis inhibitor is essential for the improvement of therapeutics against cancer. Thrombospondins-1 (TSP-1) is a potent endogenous inhibitor of angiogenesis that acts through direct effects on endothelial cell migration, proliferation, survival, and activating apoptotic pathways. TSP-1 has been shown to disrupt estrogen-induced endothelial cell proliferation and migration. Here we investigated the potential of pterostilbene carboxaldehyde thiosemicarbazone (PTERC-T), a novel resveratrol (RESV) derivative, to inhibit angiogenesis induced by female sex steroids, particularly 17β-Estradiol (E2), on Human umbilical vein endothelial cells (HUVECs) and to elucidate the involvement of TSP-1 in PTERC-T action. Our results showed that PTERC-T significantly inhibited 17β-E2-stimulated proliferation of HUVECs and induced apoptosis as determined by annexin V/propidium iodide staining and cleaved caspase-3 expression. Furthermore, PTERC-T also inhibited endothelial cell migration, and invasion in chick chorioallantoic membrane (CAM) assay. In contrast, RESV failed to inhibit 17β-E2 induced HUVECs proliferation and invasion at similar dose. PTERC-T was also found to increase TSP-1 protein expression levels in a dose-dependent manner which, however, was counteracted by co-incubation with p38MAPK or JNK inhibitors, suggesting involvement of these pathways in PTERC-T action. These results suggest that the inhibitory effect of PTERC-T on 17β-E2 induced angiogenesis is associated, at least in part, with its induction of endothelial cell apoptosis and inhibition of cell migration through targeting TSP-1. Thus, PTERC-T could be considered as a potential lead compound for developing a class of new drugs targeting angiogenesis-related diseases.

Serum levels of TSP-1, NF-κB and TGF-β1 in polycystic ovarian syndrome (PCOS) patients in northern China suggest PCOS is associated with chronic inflammation

OBJECTIVE

The objective of this study was to determine the levels of thrombospondin-1 (TSP-1), transforming growth factor-β1 (TGF-β1) and nuclear factor kappaβ (NF-κβ) in polycystic ovarian syndrome (PCOS) patients with and without insulin resistance and after treatment with cyproterone acetate/ethinyloestradiol with or without concomitant metformin.

DESIGN

Prospective.

PATIENTS

Patients with PCOS and healthy women were recruited. Patients were subdivided into obese and nonobese based on body mass index. Patients with PCOS were also grouped according to homoeostasis model assessment-insulin resistance (HOMA-IR) ≥ 2·69 or <2·69, and by PCOS phenotype. Patients with PCOS-IR were treated with a 6-month course of cyproterone acetate/ethinyloestradiol with or without concomitant metformin.

MEASUREMENTS

Inflammatory markers were examined at baseline, and after 6 months of treatment.

RESULTS

A total of 445 women with PCOS (mean age 25·9 ± 2·7 years; 298 obese, 147 nonobese) and 213 normal controls (mean age 24·9 ± 3·0 years) were included. Regardless of obesity status, testosterone, free androgen index (FAI), luteinizing hormone/follicle-stimulating hormone (LH/FSH) ratio, HOMA-IR, TSP-1 and NF-κB in the PCOS groups were significantly higher than in the control group, whereas TSP-1 was lower in the PCOS groups (all, P < 0·05). Patients with PCOS without IR had lower TSP-1 levels than control patients (P < 0·05). Treatment with cyproterone acetate/ethinyloestradiol with addition of metformin reduced the level of NF-κB, TGF-β1 and HOMA-IR and increased the level of TSP-1.

CONCLUSIONS

These results support the association between PCOS and chronic inflammation.

Functions and transcriptional regulation of thrombospondins and their interrelationship with fibroblast growth factor-2 in bovine luteal cells

Previously, we showed luteal stage-specific regulation of angiogenesis-modulating factors by prostaglandin F2 alpha (PGF2alpha). Fibroblast growth factor 2 (FGF2) and thrombospondins (THBSs) exhibited the most divergent profile of induction by PGF2alpha. We therefore examined the transcriptional regulation and roles of THBSs in luteal cells and studied their interaction with FGF2. THBSs and their receptors exhibited cell-specific expression: THBS1 was the predominant form in luteal endothelial cells (LEC), whereas luteinized granulosa cells (LGC) expressed mostly THBS2. CD36 was confined to LGC, but CD47 did not exhibit preferential expression between LEC and LGC. THBS1 and THBS2 were both stimulated in vitro by PGF2a and its analog in LGC. In contrast, luteinizing signals (LH and insulin) decreased the expression of THBS1, THBS2, and CD36. Importantly, LH increased FGF2 expression, suggesting that THBSs and FGF2 are conversely regulated. We found that FGF2 inhibited THBS1 and vice versa, and that THBS1 treatment decreased FGF2 expression, suggesting reciprocal inhibition. In agreement, ablation of THBS1 by specific small interference RNAs elevated FGF2 levels. THBS1 reduced LEC numbers and promoted apoptosis by activation of caspase-3. In contrast, FGF2 reduced basal and THBS1-induced caspase-3 levels. Consistent with these findings, small interference RNA silencing of THBS1 in luteal cells reduced the levels of active caspase-3 and improved the survival of cells when challenged with staurosporine. Taken together, these studies suggest that THBSs are suppressed during luteinization but are induced by PGF2alpha in luteolysis. THBS1 has antiangiogenic, proapoptotic properties; these, together with its ability to inhibit FGF2 expression and activity, can promote luteolysis.

Development and bioevaluation of nanofibers with blood-derived growth factors for dermal wound healing

The aim of our work was to produce a modern nanomaterial with incorporated blood-derived growth factors, produced by electrospinning, applicable in treatment of chronic wounds. Platelet-rich plasma was chosen as a natural source of growth factors. Results showed that platelet-rich plasma stimulates keratinocyte and fibroblast cell growth in vitro. Its optimal concentration in growth medium was 2% (v/v) for both types of skin cells, while higher concentrations caused alterations in cell morphology, with reduced cell mobility and proliferation. In the next step hydrophilic nanofibers loaded with platelet-rich plasma were produced from chitosan and poly(ethylene oxide), using electrospinning. The morphology of nanofibers was stable in aqueous conditions for 72 h. It was shown that electrospinning does not adversely affect the biological activity of platelet-rich plasma. The effects of nanofibers with incorporated platelet-rich plasma on cell proliferation, survival, morphology and mobility were examined. Nanofibers limited cell mobility, changed morphology and stimulated cell proliferation. Despite of the small amount of blood-derived growth factors introduced in cell culture via platelet-rich plasma-loaded nanofibers, such nanofibrillar support significantly induced cell proliferation, indicating synergistic effect of nanotopography and incorporated growth factors. The overall results confirm favorable in vitro properties of produced nanofibers, indicating their high potential as a nanomaterial suitable for delivery of platelet-rich plasma in wound healing applications.

The thrombospondin-1 receptor CD36 is an important mediator of ovarian angiogenesis and folliculogenesis

BACKGROUND

Ovarian angiogenesis is a complex process that is regulated by a balance between pro- and anti-angiogenic factors. Physiological processes within the ovary, such as folliculogenesis, ovulation, and luteal formation are dependent upon adequate vascularization and anything that disrupts normal angiogenic processes may result in ovarian dysfunction, and possibly infertility. The objective of this study was to evaluate the role of the thrombospondin-1 (TSP-1) receptor CD36 in mediating ovarian angiogenesis and regulating ovarian function.

METHODS

The role of CD36 was evaluated in granulosa cells in vitro and ovarian morphology and protein expression were determined in wild type and CD36 null mice.

RESULTS

In vitro, CD36 inhibition increased granulosa cell proliferation and decreased apoptosis. Granulosa cells in which CD36 was knocked down also exhibited an increase in expression of survival and angiogenic proteins. Ovaries from CD36 null mice were hypervascularized, with increased expression of pro-angiogenic vascular endothelial growth factor (VEGF) and its receptor VEGFR-2. Ovaries from CD36 null mice contained an increase in the numbers of pre-ovulatory follicles and decreased numbers of corpora lutea. CD36 null mice also had fewer number of offspring compared to wild type controls.

CONCLUSIONS

The results from this study demonstrate that CD36 is integral to the regulation of ovarian angiogenesis by TSP-1 and the expression of these family members may be useful in the control of ovarian vascular disorders.

Transcriptome profiling of granulosa cells from bovine ovarian follicles during atresia

Background

The major function of the ovary is to produce oocytes for fertilisation. Oocytes mature in follicles surrounded by nurturing granulosa cells and all are enclosed by a basal lamina. During growth, granulosa cells replicate and a large fluid-filled cavity (the antrum) develops in the centre. Only follicles that have enlarged to over 10 mm can ovulate in cows. In mammals, the number of primordial follicles far exceeds the numbers that ever ovulate and atresia or regression of follicles is a mechanism to regulate the number of oocytes ovulated and to contribute to the timing of ovulation. To better understand the molecular basis of follicular atresia, we undertook transcriptome profiling of granulosa cells from healthy (n = 10) and atretic (n = 5) bovine follicles at early antral stages (< 5 mm).

Results

Principal Component Analysis (PCA) and hierarchical classification of the signal intensity plots for the arrays showed primary clustering into two groups, healthy and atretic. These analyses and size-frequency plots of coefficients of variation of signal intensities revealed that the healthy follicles were more heterogeneous. Examining the differentially-expressed genes the most significantly affected functions in atretic follicles were cell death, organ development, tissue development and embryonic development. The overall processes influenced by transcription factor gene TP53 were predicted to be activated, whereas those of MYC were inhibited on the basis of known interactions with the genes in our dataset. The top ranked canonical pathway contained signalling molecules common to various inflammatory/fibrotic pathways such as the transforming growth factor-β and tumour necrosis factor-α pathways. The two most significant networks also reflect this pattern of tissue remodelling/fibrosis gene expression. These networks also contain molecules which are present in the canonical pathways of hepatic fibrosis/hepatic stellate cell activation and transforming growth factor-β signalling and were up regulated.

Conclusions

Small healthy antral follicles, which have a number of growth outcomes, exhibit greater variability in gene expression, particularly in genes associated with cell division and other growth-related functions. Atresia, on the other hand, not only involves cell death but clearly is an active process similar to wound healing.

The distinguishing cellular and molecular features of the endometriotic ovarian cyst: from pathophysiology to the potential endometrioma-mediated damage to the ovary

BACKGROUND

Clinical data suggest that the presence of an ovarian endometrioma may cause per se damage to the surrounding otherwise healthy ovarian tissue. However, the basic research has so far done a limited job in trying to understand the potential detrimental effect of an endometrioma presence in the context of the ovarian physiology. We have reviewed the literature with the aim of characterizing the pathophysiology of the endometrioma focusing mostly on factors and mechanisms potentially affecting the surrounding, otherwise normal, ovarian tissue.

METHODS

Comprehensive searches of PUBMED were conducted to identify human studies published from 1991 to 2013 in the English language on the cellular and molecular characterization of the various endometrioma components.

RESULTS

An endometrioma contains free iron, reactive oxygen species (ROS), proteolytic enzymes and inflammatory molecules in concentrations from tens to hundreds of times higher than those present in peripheral blood or in other types of benign cysts. The cyst fluid causes substantial changes in the endometriotic cells that it baths from gene expression modifications to genetic mutations The physical barrier between the cyst contents and the normal ovarian tissue is a thin wall composed of the ovarian cortex itself or fibroreactive tissue. ROS potentially permeating the surrounding tissues and proteolytic substances degrading the adjacent areas are likely to cause the substitution of normal ovarian cortical tissue with fibrous tissue in which the cortex-specific stroma is reduced. The fibrosis is associated with smooth muscle metaplasia and followed by follicular loss and intraovarian vascular injury. Follicular density in tissue surrounding the endometriotic cyst was consistently shown to be significantly lower than in healthy ovaries but this pathological change does not appear to be caused by the stretching of surrounding tissues owing to the presence of a cyst.

CONCLUSIONS

There is sufficient molecular, histological and morphological evidence, in part deriving from knowledge of the pathophysiology, to support a deleterious effect of the endometrioma on the adjacent ovarian cortical tissue, independent of the mere mechanical stretching owing to its size.

Targeting angiogenesis in the pathological ovary

The ovary is a key tissue in the study of physiological neo-vascularisation in the adult and its study has highlighted important molecules involved in the regulation of angiogenesis in vivo. These include vascular endothelial growth factor, delta-like ligand 4, thrombospondin-1, prokineticin-1 and prostaglandin E2. Targeting these molecular pathways has therapeutic potential and their manipulation has an increasing preclinical and clinical role in the management of the pathological ovary. Targeting angiogenic pathways has utility in the promotion of ovarian angiogenesis to improve tissue and follicle survival and function as well as the prevention and management of ovarian hyperstimulation syndrome. There is a theoretical possibility that targeting angiogenesis may improve the function of the polycystic ovary and a real role for targeting angiogenesis in ovarian cancer.

Differential gene expression of granulosa cells after ovarian superstimulation in beef cattle

Microarray analysis was used to compare the gene expression of granulosa cells from dominant follicles with that of those after superstimulatory treatment. Cows were allocated randomly to two groups (superstimulation and control, n=6/group). A new follicular wave was induced by ablation of follicles ≥5 mm in diameter, and a progesterone-releasing device controlled internal drug release (CIDR) was placed in the vagina. The superstimulation group was given eight doses of 25 mg FSH at 12-h intervals starting from the day of wave emergence (day 0), whereas the control group was not given FSH treatment. Both groups were given prostaglandin F2α twice, 12 h apart, on day 3 and the CIDR was removed at the second injection; 25 mg porcine luteinizing hormone (pLH) was given 24 h after CIDR removal, and cows were ovariectomized 24 h later. Granulosa cells were collected for RNA extraction, amplification, and microarray hybridization. A total of 190 genes were downregulated and 280 genes were upregulated. To validate the microarray results, five genes were selected for real-time PCR (NTS, FOS, THBS1, FN1, and IGF2). Expression of four genes increased significantly in the three different animals tested (NTS, FOS, THBS1, and FN1). The upregulated genes are related to matrix remodeling (i.e. tissue proliferation), disturbance of angiogenesis, apoptosis, and oxidative stress response. We conclude that superstimulation treatment i) results in granulosa cells that lag behind in maturation and differentiation (most of the upregulated genes are markers of the follicular growth stage), ii) activates genes involved with the NFE2L2 oxidative stress response and endoplasmic reticulum stress response, and iii) disturbs angiogenesis.

Caffeine-induced endothelial cell death and the inhibition of angiogenesis

Numerous studies have shown that adenosine or adenosine agonists can stimulate angiogenesis. However, the effect of caffeine (a known adenosine receptor antagonist) on angiogenesis has not been previously studied. Accordingly, this study was undertaken to examine the effect of caffeine on angiogenesis and to clarify the mechanism involved. Chick chorioallantoic membrane assays were used to investigate the effect of caffeine on angiogenesis and proliferation assays using human umbilical vein endothelial cells (HUVECs), were used to study its effects on specific aspects of angiogenesis. The expressions of caspase-3 and Bcl-2 were examined by western blotting, immunofluorescence staining was used to identify HUVEC morphological changes, and fluorescence activated cell sorting (FACS) and DAPI staining were used to detect HUVEC apoptosis. Caffeine was found to inhibit blood vessel formation dose-dependently and to inhibit the proliferation of HUVECs time- and dose-dependently. FACS analysis and DAPI staining showed that inhibitory effect of caffeine on HUVEC proliferation was the result of apoptosis and the up-regulation of thrombospondin-1 (TSP-1). Furthermore, TSP-1 levels were down-regulated by NECA but were unaffected by CGS21680, indicating that caffeine regulated TSP-1 expression via adenosine A2B receptor. In addition, caffeine up-regulated caspase-3 and down-regulated Bcl-2 at the protein level. These results suggest that the inhibitory effect of caffeine on angiogenesis is associated, at least in part, with its induction of endothelial cell apoptosis, probably mediated by a caspase-3 dependent mechanism.

Estradiol supports in vitro development of bovine early antral follicles

Antrum formation and estradiol (E2) secretion are specific features of oocyte and granulosa cell complexes (OGCs). This study investigates the effect of E2 on the in vitro development of bovine OGCs derived from early antral follicles as well as on the expression of genes in granulosa cells (GCs). The supplementation of culture medium with either E2 or androstenedione (A4) improved the in vitro development of OGCs and the nuclear maturation of enclosed oocytes. When OGCs were cultured in medium containing A4, developmentally competent OGCs secreted more E2 than OGCs that were not competent. In addition, fulvestrant inhibited the effect of both E2 and A4 on OGCs development. Comprehensive gene expression analysis using next-generation sequence technology was conducted for the following three types of GCs: i) GCs of OGCs cultured for 4 days with E2 (1 μg/ml; E2(+)), ii) GCs of OGCs cultured for 4 days without E2 (E2(−)) or iii) OGCs that formed clear antrum after 8 days of in vitro culture in medium containing E2 (1 μg/ml; AF group). GCs of the E2(+) group had a similar gene expression profile to the profile reported previously for the in vivo development of large follicles. This genetic profile included factors implicated in the up-regulation of E2 biosynthesis and down-regulation of cytoskeleton and extracellular matrices. In addition, a novel gene expression profile was found in the AF group. In conclusion, E2 impacts the gene expression profile of GCs to support the in vitro development of OGCs.

Hormonal regulation of pigment epithelium-derived factor (PEDF) in granulosa cells

Angiogenesis is critical for the development of ovarian follicles. Blood vessels are abrogated from the follicle until ovulation, when they invade it to support the developing corpus luteum. Granulosa cells are known to secrete anti-angiogenic factors that shield against premature vascularization; however, their molecular identity is yet to be defined. In this study we address the physiological role of pigment epithelium-derived factor (PEDF), a well-known angiogenic inhibitor, in granulosa cells. We have shown that human and mouse primary granulosa cells express and secrete PEDF, and characterized its hormonal regulation. Stimulation of granulosa cells with increasing doses of estrogen caused a gradual decrease in the PEDF secretion, while stimulation with progesterone caused an abrupt decrease in its secretion. Moreover, We have shown, by time- and dose-response experiments, that the secreted PEDF and vascular endothelial growth factor (VEGF) were inversely regulated by hCG; namely, PEDF level was nearly undetectable under high doses of hCG, while VEGF level was significantly elevated. The anti-angiogenic nature of the PEDF secreted from granulosa cells was examined by migration, proliferation and tube formation assays in cultures of human umbilical vein endothelial cells. Depleting PEDF from primary granulosa cells conditioned media accelerated endothelial cells proliferation, migration and tube formation. Collectively, the dynamic expression of PEDF that inversely portrays VEGF expression may imply its putative role as a physiological negative regulator of follicular angiogenesis.

Regulation of angiogenesis-related prostaglandin f2alpha-induced genes in the bovine corpus luteum

We recently compared prostaglandin F2alpha (PG)-induced global gene expression profiles in PG-refractory, bovine corpus luteum (CL) collected on Day 4 of the estrous cycle, versus PG-responsive, Day 11 CL. Transcriptome analyses led us to study the regulation of angiogenesis-related genes by PG and their functions in luteal endothelial cells (ECs). We found that PG regulated angiogenesis-modulating factors in a luteal stage-dependent way. A robust increase in FGF2 expression (mRNA and protein) occurred in the PG-refractory Day 4 CL promoting CL survival and function. Inhibitors of FGF2 action, thrombospondin 1 and 2, their receptor (CD36), and PTX3 were upregulated by PG specifically in Day 11 CL undergoing luteolysis. VEGF mRNA decreased 4 h post-PG in both Day 4 and Day 11 CL. The resulting destabilization of blood vessels in Day 11 CL is expected to weaken the gland and reduce its hormonal output. These genes were expressed in dispersed luteal ECs and steroidogenic cells; however, thrombospondin 1 and FGF2 were more abundant in luteal ECs. Expression of such genes and their ability to modulate FGF2 actions were investigated. Similar to its in vivo effect, PG, in vitro, stimulated the expression of thrombospondins and PTX3 genes in several luteal cell models. Importantly, these factors influenced the angiogenic properties of luteal ECs. FGF2 dose-dependently enhanced cell migration and proliferation, whereas thrombospondin 1 and PTX3 inhibited FGF2 actions in luteal ECs. Collectively, the data presented here suggest that, by tilting the balance between pro- and antiangiogenic factors, PG can potentially control the ability of the CL to resist or advance toward luteolysis.

Therapies using anti-angiogenic peptide mimetics of thrombospondin-1

INTRODUCTION

The role of hrombospondin-1 (TSP1) as a major endogenous angiogenesis inhibitor has been confirmed by numerous studies and subsequent mechanistic discoveries. It has yielded a new class of potential drugs against cancer and other angiogenesis-driven diseases.

AREAS COVERED

An overview of TSP1 functions and molecular mechanisms, including regulation and signaling. Functions in endothelial and non-endothelial cells, with emphasis on the role of TSP1 in the regulation of angiogenesis and inflammation. The utility of duplicating these activities for drug discovery. Past and current literature on endogenous TSP1 and its role in the progression of cancer and non-cancerous pathological conditions is summarized, as well as the research undertaken to identify and optimize short bioactive peptides derived from the two TSP1 anti-angiogenic domains, which bind CD47 and CD36 cell surface receptors. Lastly, there is an overview of the efficacy of some of these peptides in pre-clinical and clinical models of angiogenesis-dependent disease.

EXPERT OPINION

It is concluded that TSP1-derived peptides and peptide mimetics hold great promise as future agents for the treatment of cancer and other diseases driven by excessive angiogenesis. They may fulfill unmet medical needs including neovascular ocular disease and the diseases of the female reproductive tract including ovarian cancer.

Immediate early inflammatory gene responses of human umbilical vein endothelial cells to hemorrhagic venom

OBJECTIVE AND DESIGN

This report describes a focused immediate early gene response by human umbilical vein endothelial cells (HUVEC) to Echis carinatus snake venom.

MATERIALS OR SUBJECTS

Primary cultures of HUVEC were used to assess acute inflammatory gene responses.

TREATMENTS

Crude E. carinatus venom (2.5 µg/ml) was used to stimulate HUVEC.

RESULTS

HUVEC stimulated for 3 h with E. carinatus venom showed a focused response to the venom, with significant increases in metallothionein (e.g., MT1H, MT2A, MT1X) and cytochrome P450 (e.g., CYP1A1, CYP1B1) gene expressions compared to non-stimulated controls. Several other genes involved in cell growth and matrix attachment were repressed [e.g., thrombospondin 1 (THBS1), connective tissue growth factor (CTGF)].

CONCLUSIONS

These data suggest that acute vascular injury induced by hemorrhagic snake venom initiates an anti-oxidant response primarily involving metallothioneins.

A thrombospondin-mimetic peptide, ABT-898, suppresses angiogenesis and promotes follicular atresia in pre- and early-antral follicles in vivo

Using a novel in vitro angiogenesis assay, we previously showed that thrombospondin (TSP)-1 has antiangiogenic effects on rat follicles and induces apoptosis in granulosa cells in vitro. ABT-898 is an octapeptide mimetic of TSP-1 closely related to ABT-510. Here, we demonstrate the inhibitory effects of ABT-898 on follicular angiogenesis and its proapoptotic effect on granulosa cells. To investigate the potential of this peptide to inhibit follicular angiogenesis in vivo, marmoset monkeys were treated with 2.5 mg/kg ABT-898 twice daily throughout the follicular phase of the cycle. Although treatment did not block emergence of dominant follicles, angiogenesis was reduced in preantral and early-antral follicles. Furthermore, the incidence of atresia at these follicle stages was increased. To investigate whether treatment with ABT-898 would interfere with the timing or duration of the normal ovulatory rise in plasma progesterone, marmosets were treated with a depot formulation containing 25 mg ABT-898 at the start of the follicular phase, with a second injection after 2 wk. Despite active concentrations of peptide being maintained in the circulation, no apparent effects on the ovulatory cycle were observed. Taken together, these results indicate that ABT-898 is capable of having a dual effect by inhibiting follicular angiogenesis and promoting atresia of antral follicles in vivo but does not prevent ovulation or induce luteolysis, as has been observed with direct vascular endothelial growth factor inhibitors. These results suggest that ABT-898 could be a novel therapeutic to inhibit abnormal angiogenesis and induce atresia of accumulated follicles in polycystic ovary syndrome.