Analysis of the cytokine interaction among interleukin-1beta, interleukin-8, and interleukin-1 receptor antagonist in the rabbit ovulatory process

Participation of follicular superoxides, inflammatory modulators, and endocrine factors in zebrafish (Danio rerio) ovulation: Cross-talk between PKA and MAPK signaling in Pgr regulation of ovulatory markers

The ovulatory response involves diverse molecular determinants, the interplay between which remains less investigated in fish. This study explores the temporal changes in the follicular microenvironment, regulatory factors, and underlying signaling events during ovulation in female zebrafish subjected to 14L:10D at 28 ± 1 °C in vivo vis-à-vis in hCG-stimulated full-grown (FG) follicles in vitro. Congruent with reduced GSH levels, SOD, and GPx activity, a graded increase in follicular free radicals, Nox4, and p38 MAPK phosphorylation in the morning hour groups (05:00 and 06:30) correlates positively with the ovulatory surge in inflammatory mediators (Tnf-α, Il-1β, Il-6, Nos2, and Cox-2). Further, elevated Pgr expression and its nuclear translocation, congruent with follicular lhcgr, star, and hsd20b2 upregulation in vivo, corroborates well with the transcriptional activation of genes (pla2g4aa, ptgesl, ptger4b, mmp9, adamts9), triggering ovulation in this species. Mechanistically, an elevated ovulatory response in hCG-treated FG follicles in vitro involves the upregulation of inflammatory mediators, pgr and ovulation-associated genes in a manner sensitive to PKA- and MAPK3/1-mediated signaling.

Ovulation Induced by Intrauterine Seminal Plasma Increases Total Protein, PGE2, IL-8, and IL-1β in Uterine Fluid of Llamas (Lama glama)

The establishment of a state of immunotolerance in the female reproductive tract is important for embryo development, implantation and placentation. Llamas are induced ovulators and more than 98% of pregnancies occur in the left uterine horn. The objective of this study was to determine the uterine immune response of llamas in different stages of the reproductive cycle. Adult llamas (n = 20) were examined daily by transrectal ultrasonography to determine follicular growth and then randomly assigned to four groups: Follicular phase (n = 5); Luteal phase induced by an intramuscular administration of 50 ug of GnRH analogue (n = 5); Luteal phase induced by intrauterine infusion of seminal plasma (n = 5); and Luteal phase induced by mating (n = 5). Uterine fluid was collected separately from both uterine horns by non-surgical flushing to determine the presence of cells, total proteins and concentration of IL-1β, IL-6, IL-8, IFN γ, TNF-α and PGE2. Inflammatory cells were not observed in the uterine fluid and total protein pattern and inflammatory mediators did not differ between the left and the right horn amongst groups. Llamas treated with an intrauterine infusion of seminal plasma showed the highest concentration of total proteins, inflammatory cytokines PGE2, IL-8 and IL-1β in the uterine fluid. In conclusion, seminal plasma is made up of significant numbers of signaling molecules that are able to modify the uterine immune response in llamas.

Rapid and transient upregulation of CCL11 (eotaxin-1) in mouse ovary during terminal stages of follicular development

PROBLEM

This study aimed to investigate the regulation of expression, localization and physiological role of the CCL11/CCR3 axis in mouse ovary during the periovulatory period.

METHOD OF STUDY

CCL11/CCR3 expression in the mouse ovary after treatment with pregnant mare serum gonadotropin (PMSG) followed by human chorionic gonadotropin (hCG) 48 hr later was assessed in vivo and in 3-dimensional cultures in vitro.

RESULTS

Real-time RT-PCR analyses revealed transient CCL11 mRNA upregulation 6 hr after hCG treatment. Immunohistochemical staining of serial ovarian sections demonstrated overlapping expression of CCL11, CCR3 and CD31 endothelial cell marker in the theca-interstitial layer at 10 hr after hCG treatment. In vitro 3-dimensional cultures of periovulatory ovarian tissues demonstrated that treatment with anti-CCL11 neutralizing antibody significantly decreased CD31 transcript.

CONCLUSIONS

Gonadotropin surge leads to transient CCL11/CCR3 axis upregulation in the ovarian theca-interstitial layer, suggesting that it is involved in periovulatory physiological processes by affecting follicular vessels.

Transient expression of CC chemokine TECK in the ovary during ovulation: its potential role in ovulation

PROBLEM

Chemokine thymus-expressed chemokine (TECK), which is expressed exclusively in the thymus and small intestine, plays a critical role in T-cell development. Our previous study revealed its expression in the ovary also. This study investigated its ovarian expression during ovulatory process.

METHOD OF STUDY

Super-ovulation was induced in young female CD1 mice by equine chorionic gonadotropin (eCG) and human chorionic gonadotropic (hCG). Ovarian TECK expression during ovulation was determined by: (1) reverse transcriptase-polymerase chain reaction (RT-PCR) at mRNA level, (2) Western blot and immunohistology at the protein level, and (3) leukocyte infiltration assay at the bioactive level.

RESULTS

A transient, high-level expression of TECK in murine ovaries at the mRNA level during hCG-induced ovulation was detected. Sequencing of directly cloned PCR product confirmed the ovarian expression of TECK. The peak expression of TECK was observed at 10-12 hr post-hCG injection; real-time PCR revealed an 800-fold increase during its expression peak over 0 hr. The expressed ovarian TECK protein was readily detectable by Western blot. Immunohistochemistry localized TECK expression to the ovarian interstitial tissue surrounding, or in the theca layer of the mature follicles undergoing ovulatory process. Expression of TECK receptor, the CC chemokine receptor (CCR9) was also detected in the ovulating ovaries. Using in vitro leukocyte infiltration assay, we first demonstrated that ovaries undergoing the ovulatory process were able to selectively chemoattract mononuclear cells. Importantly, neutralization of TECK by the antibody resulted in a 85% reduction in the chemotactic activities of the ovaries.

CONCLUSION

This study suggested that ovarian expression of TECK is under a tight hormonal regulation, and expressed TECK may be responsible for recruitment of mononuclear cells into the ovary to participate in the ovulatory process.

Preservation of tear film integrity and inhibition of corneal injury by dexamethasone in a rabbit model of lacrimal gland inflammation-induced dry eye

PURPOSE

The aim of this study was to establish a clinically relevant short-term animal model of dry eye with utility in identifying compounds with potential therapeutic efficacy.

METHODS

Rabbit lacrimal glands were injected with the T-cell mitogen Concanavalin A (Con A) and inflammation, tear function, and corneal epithelial cell integrity were subsequently assessed. The inflammatory response was characterized by quantifying biochemical markers of inflammation ex vivo and by confirming inflammatory cell influx by histology. Matrix metalloproteinase-9 (MMP-9) and proinflammatory cytokines IL-1beta, IL-8, and TGF-beta1 were quantified in tissue extracts. Tear function was monitored by measuring tear fluorescein clearance and tear breakup time (TBUT). Corneal epithelial cell integrity was determined by quantifying the uptake of methylene blue dye following the exposure of rabbits to a low-humidity environment. The anti-inflammatory corticosteroid, dexamethasone, was administered topically as indicated for each study.

RESULTS

Histopathologic evaluation of lacrimal glands injected with Con A revealed a pronounced inflammatory process characterized by lymphocytic infiltration, multifocal necrosis, and fibroplasia. Elevated levels of MMP-9 and cytokines IL-1beta, IL-8, and TGF-beta1 were detected in the lacrimal gland and cornea. Inflammation of the rabbit lacrimal gland following an injection of Con A significantly reduced tear clearance and TBUT and increased susceptibility to desiccation-induced corneal damage. Dexamethasone was prophylactically and therapeutically effective in this inflammation model of dry eye, restoring tear function and inhibiting corneal injury following topical ocular application.

CONCLUSIONS

Characteristics of this rabbit lacrimal gland inflammation model of dry eye are consistent with the current understanding of dry eye as a local ocular surface inflammatory response to abnormal tear volume and composition. These results suggest that this rabbit model of dry eye may be employed to assess the therapeutic efficacy of mechanistically diverse agents on clinically relevant signs of ocular surface disease. These methods were strategically developed to be applicable for advancing drug discovery for a broad spectrum of dry eye patients.

Interleukin-8 gene and protein expression are up-regulated by interleukin-1beta in normal human ovarian cells and a granulosa tumor cell line

OBJECTIVE

To evaluate the expression, regulation, and role of interleukin (IL)-8 in human ovary.

DESIGN

Prospective study.

SETTING

University hospital.

PATIENT(S)

Sixteen premenopausal women.

INTERVENTION

Follicular fluid and granulosa lutein cells (GLCs) were collected during IVF cycles. Ovarian stromal and theca cells were obtained from women underwent surgery. KGN cells, the human granulosa cell tumor cell line, were also used.

MAIN OUTCOME MEASURES

The levels of IL-8 and IL-1beta in follicular fluid and IL-8 protein production were determined using ELISA. Interleukin-8 and IL-8 receptor gene expression in ovarian cells and the effect of IL-8 on the proliferation of stromal cells were determined. The expression of pIkappaB was evaluated by Western blot, and the effect of NF-kappaB inhibitor APDC was examined by Northern blot analysis and ELISA in KGN cells. The levels of IL-8 and IL-1beta in follicular fluid; each concentration and the volume showed a positive correlation. Reverse transcription polymerase chain reaction showed the presence of IL-8 mRNA in all ovarian cells. In contrast, IL-8 receptor mRNA was only detected in stromal cells. The expression of IL-8 in GLCs and KGN cells was increased by addition of IL-1beta and TNFalpha. Interleukin-8 increased the proliferation of ovarian stromal cells. The expression of pIkappaB in KGN cells was induced by IL-1beta, and the effects were reduced by APDC.

CONCLUSION(S)

Interleukin 8 induced by IL-1beta via activation of NF-kappaB in granulosa cells may have a role in the periovulatory period of follicular maturation.

Relationship between ovarian stimulation regimen and interleukin level in pre-ovulatory follicular fluid and their effect on ICSI outcome

PROBLEM

The aims of this study were (i) to identify the presence and concentration of interleukin-6 (IL-6), IL-8 and granulocyte-macrophage colony-stimulating factor (GM-CSF) in pre-ovulatory follicular fluid (FF) in patients undergoing controlled ovarian hyperstimulation regimen for intracytoplasmic sperm injection (ICSI) with recombinant human follicle stimulating hormone (rFSH) (G.1), hMG (G.2) or rFSH/ hMG (G.3) treatment and (ii) to determine whether controlled ovarian hyperstimulation stimulation regimen could affect the concentration of these investigated interleukins and as a consequences the ICSI outcome. (iii) Moreover, it was intended to clarify the association between these investigated parameters and the peripheral blood level of estradiol 17-beta, progesterone, leuteinizing hormone (LH) at the day of oocyte retrieval and (iv) finally to find out whether these interleukin concentrations in FF could be considered as an additional parameter for predicting fertilization and pregnancy outcome in ICSI patients.

MATERIAL AND METHODS

Interleukin-6, IL-8 and GM-CSF concentrations were determined in the FF of 85 patients. The levels of these interleukins were measured by the enzyme-linked immunosorbent assay (ELISA) technique, using commercially available kits.

RESULTS

Interleukin-6 (6.5 +/- 4.6 pg/mL), IL-8 (222.9 +/- 163.4 pg/mL) and GM-CSF (1.6 +/- 2.7 pg/mL) were present in pre-ovulatory FF in ICSI patients. No significant difference in the mean concentration of IL-6, IL-8 and GM-CSF was found between the groups. Moreover, there was no correlation between these interleukin levels in FF and steroid hormone concentration in the peripheral blood.

CONCLUSIONS

Interleukin-6, IL-8 and GM-CSF were found in FF of patients undergoing ovarian hyperstimulation for ICSI treatment. The stimulation protocols showed no influence on these interleukin levels in FF. Moreover, no correlation was found between these investigated interleukins and steroid hormone concentrations in peripheral blood or ICSI outcome. Therefore, the determination of interleukin level in FF of patients undergoing ovarian hyperstimulation for ICSI therapy could not be recommended as a prognostic factor for ICSI outcome.

Expression, hormonal regulation, and cyclic variation of chemokines in the rat ovary: key determinants of the intraovarian residence of representatives of the white blood cell series

A growing body of evidence suggests that mammalian ovulation bears similarities to local inflammatory reactions. Monocytes/macrophages, eosinophils, and neutrophils are known to infiltrate the area surrounding the dominant follicle before ovulation. Candidate local chemoattractants may include a family of small cytokines, also known as chemokines. In the present study, quantitative RT-PCR was used to initially identify and quantify the chemokines expressed in the preovulatory rat ovary. The chemokines monocyte chemotatic protein 1 (MCP-1), MCP-3, macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-1beta, MIP-1gamma, regulated upon activation normal T cell expressed and secreted, eotaxin, interferon-inducible protein of 10 kDa, growth-regulated oncogene, lymphotactin, and fractalkine were all expressed in the PMSG-primed rat ovary 6 h post human CG. C10, T cell activation gene 3, exodus, exodus-2, cytokine-induced neutrophil chemoattractant-2, MIP-2, and lipopolysaccharide-induced C-X-C were not expressed in the PMSG-primed rat ovary 6 h post human CG. The cyclic variation of the ovary-positive chemokines was also evaluated throughout the course of a superovulated ovarian cycle. Significant preovulatory up-regulation relative to the untreated control state was documented for MCP-1 (18-fold), MCP-3 (12-fold), and growth-regulated oncogene (25-fold). In contrast, the preovulatory ovarian expression of eotaxin, fractalkine and regulated upon activation normal T cell expressed and secreted was not increased. These observations suggest that intraovarian chemokines may be responsible for the cyclic intraovarian residence of representatives of the white blood cell series.

Expression of tumor necrosis factor-stimulated gene-6 in the rat ovary in response to an ovulatory dose of gonadotropin

Current evidence supports the hypothesis that the biochemical events of mammalian ovulation are analogous to an acute inflammatory reaction. This study reveals that tumor necrosis factor-stimulated gene-6 (TSG-6), which encodes a member of the superfamily of hyaluronan-binding proteins that is specifically translated in inflammatory reactions, is expressed in ovarian follicles that have been induced to ovulate. Immature Wistar rats were primed with 10 IU equine CG s.c.; and 48 h later, the 12-h ovulatory process was initiated by 10 IU human CG (hCG), s.c.. Ovarian RNA was extracted at 0, 2, 4, 8, 12, and 24 h after the primed animals were injected with hCG. The RNA extracts were used for RT-PCR differential display of amplified complementary DNAs (cDNAs) that represented gene expression in the stimulated ovarian tissue. Northern analysis of one of the differentially amplified cDNAs confirmed that it was part of a gene that was substantially up-regulated at 4-8 h after the ovaries had been stimulated by hCG. Subcloning and sequence analysis revealed that the cDNA matched the gene for TSG-6. In situ hybridization indicated that the TSG-6 messenger RNA was primarily located in the cumulus mass and the antral granulosa cells of large ovarian follicles. In conclusion, the data show that expression of TSG-6 is an integral part of the cascade of inflammatory-like changes that occur in an ovulatory follicle in response to a trophic hormone that couples with luteinizing hormone/hCG receptors.

Production and regulation of cytokine-induced neutrophil chemoattractant in rat ovulation

A cytokine-induced neutrophil chemoattractant (CINC/gro), which belongs to the interleukin (IL)-8 family, acts as a functional chemoattractant for neutrophils in rats. In the present study, we examined whether CINC/gro contributes to the ovulation process in the rat ovulation system. In rat ovaries, CINC/gro was immunohistochemically recognized in the theca layer of the antral follicle but not in the granulosa cells. To clarify the role of CINC/gro in the ovulation process, CINC/gro protein and mRNA were examined during pregnant mare serum gonadotropin (PMSG)-hCG treatment. CINC/gro protein did not increase as a result of PMSG injection. However, it increased rapidly after hCG injection and peaked at 6 h after hCG. CINC/gro mRNA was also strongly expressed after hCG injection. The increase of CINC/gro protein followed increases in IL-1beta and tumor necrosis factor alpha (TNFalpha). In the whole ovarian dispersate culture, FSH, hCG, IL-1beta, and TNFalpha stimulated the production of CINC/gro protein in a dose-dependent manner. In particular, the stimulatory effects of IL-1beta and TNFalpha were stronger than those of gonadotropins. These results suggest that CINC/gro plays an important role in the rat ovulation process by attracting neutrophils. CINC/gro increased just prior to ovulation, and it may be regulated directly by cytokines such as IL-1beta and TNFalpha and indirectly by gonadotropins.