Vascular endothelial growth factor, interleukin-6 and interleukin-2 in serum and follicular fluid of patients with ovarian hyperstimulation syndrome

Intrafollicular fluid metabolic abnormalities in relation to ovarian hyperstimulation syndrome: Follicular fluid metabolomics via gas chromatography-mass spectrometry

INTRODUCTION

Ovarian hyperstimulation syndrome (OHSS) is the most serious iatrogenic complication of ovulation stimulation during assisted reproductive technology. The main objective of this study was to investigate intrafollicular fluid metabolic change profiles of OHSS in non-ovarian etiologic infertility women (CON) and polycystic ovarian syndrome patients (PCOS).

METHODS

87 infertile women were divided into four subgroups: CON-Norm (CON with normal ovarian response), CON-OHSS (CON with OHSS), PCOS-Norm (PCOS with normal ovarian response), and PCOS-OHSS (PCOS with OHSS). The intrafollicular fluid metabolic profiles were analyzed with gas chromatography-mass spectrometry. The multivariable-adjusted conditional logistic regression was applied to assess the association of metabolites with OHSS risk.

RESULTS

We identified 17 and 3 metabolites that related to OHSS risk in CON and PCOS, respectively. 13 OHSS risk-related metabolites in CON were unsaturated fatty acids, 8 of which were also the significantly altered metabolites between all PCOS and CON-Norm.

CONCLUSION

Our study may shed light on the role of intrafollicular fluid metabolic abnormalities in the pathophysiology of OHSS. The findings suggested that there might be some metabolic heterogeneities underlying the development of OHSS in CON and PCOS women and indicated possible shared etiological factors in the development of PCOS and OHSS.

Brain edema after oocyte retrieval: a case report

BACKGROUND

Brain edema is a rare and serious complication of assisted reproductive technology (ART). The increased intracranial pressure and injured brain parenchyma are life-threatening and may even result in death. The pathogenesis may involve increased vascular permeability mediated by vascular endothelial growth factor and other vasoactive substances, including interleukin 6, interleukin 1β, angiotensin II, insulin-like growth factor 1, transforming growth factor β, and the renin-angiotensin system.

CASE PRESENTATION

We presented a unique case report of a 29-year-old woman developed sudden irritability, blurred consciousness, and vomiting 8 h after oocyte retrieval. Blood examinations showed hyponatremia and cranial computed tomography showed swelling of the brain parenchyma. After therapeutic use of hypertonic saline and mannitol infusion, the patient's consciousness recovered and her neurological state improved.

CONCLUSIONS

Brain edema is a rare and serious complication of ART. Quick infusion of hypertonic salt solution and mannitol is a key treatment. A good prognosis can be achieved after prompt treatment.

Electroacupuncture Reduces Oocyte Number and Maintains Vascular Barrier Against Ovarian Hyperstimulation Syndrome by Regulating CD200

Ovarian hyperstimulation syndrome (OHSS) is a common complication caused by ovulatory stimulation therapy, which manifests as an increase in ovarian volume, an increase in the number of oocytes retrieved, and increased vascular permeability throughout the body and especially in ovarian tissue. In our previous study, we found that electroacupuncture (EA) could prevent the progression of OHSS, by mainly affecting ovary. However, the specific molecules and the mechanism of this process were still unknown. In order to explore the underlying mechanism, OHSS rat model was established and EA treatment was performed, which was followed by proteomic analysis of ovaries. Results showed a significant increase in the expression level of CD200 in the ovaries of OHSS group treated with EA than those of OHSS group. Clinical data showed that the level of CD200 in follicular fluid was negatively correlated with the number of oocytes retrieved and serum E2 level. Further in vitro experiments showed a concentration-dependent role of human chorionic gonadotropin (hCG) in reducing CD200 and CD200R levels, and increasing inflammatory cytokine levels in cultured KGN cells. In human umbilical vein endothelial cells (HUVECs), the vascular barrier function was improved by CM (cultural medium from KGN cell) which treated with CD200Fc (CD200R agonist). Meanwhile, the results of in vivo experiments indicated that EA reduced the number of ovarian corpora lutea, decreased inflammatory response, and improved the vascular barrier function by increasing the expression of CD200 and CD200R in rat ovaries. These findings suggest that EA treatment may reduce oocyte number and maintain vascular barrier against OHSS through ovarian anti-inflammatory response mediated by CD200. Therefore, this study is the first to identify CD200 as a main of EA in the ovary and elucidate the possible mechanism of EA on preventing and treating OHSS, which provide a scientific basis for CD200 as an effector and indicator in EA treatment.

Liver X Receptors: A Possible Link between Lipid Disorders and Female Infertility

A close relationship exists between cholesterol and female reproductive physiology. Indeed, cholesterol is crucial for steroid synthesis by ovary and placenta, and primordial for cell structure during folliculogenesis. Furthermore, oxysterols, cholesterol-derived ligands, play a potential role in oocyte maturation. Anomalies of cholesterol metabolism are frequently linked to infertility. However, little is known about the molecular mechanisms. In parallel, increasing evidence describing the biological roles of liver X receptors (LXRs) in the regulation of steroid synthesis and inflammation, two processes necessary for follicle maturation and ovulation. Both of the isoforms of LXRs and their bona fide ligands are present in the ovary. LXR-deficient mice develop late sterility due to abnormal oocyte maturation and increased oocyte atresia. These mice also have an ovarian hyper stimulation syndrome in response to gonadotropin stimulation. Hence, further studies are necessary to explore their specific roles in oocyte, granulosa, and theca cells. LXRs also modulate estrogen signaling and this could explain the putative protective role of the LXRs in breast cancer growth. Altogether, clinical studies would be important for determining the physiological relevance of LXRs in reproductive disorders in women.

Electroacupuncture decreases the progression of ovarian hyperstimulation syndrome in a rat model

This study aimed to elucidate the effect of electroacupuncture treatment on preventing early ovarian hyperstimulation syndrome (OHSS) and the potential mechanisms involved using an induced rat model. The ovarian response was examined by measuring ovary weight, vascular permeability, levels of inflammation (interleukin-6), tumour necrosis factor alpha, chemokine ligand 2 (also known as monocyte chemoactic protein 1), vascular endothelial growth factor and hormone concentrations (oestradiol, progesterone, testosterone and prolactin). Sprague-Dawley female rats underwent ovarian stimulation to induce OHSS. Hyperstimulated rats received consecutive electroacupuncture treatment from 3 days before the beginning of pregnant mare serum gonadotrophin treatment or the time point of pregnant mare serum gonadotrophin treatment respectively, and last until 3 days after HCG administration. Electroacupuncture treatment reduced ovary weight and vascular permeability in hyperstimulated rats. Electroacupuncture treatment also reduced the levels of serum steroid hormones (progesterone and testosterone), inflammatory cytokines (interleukin-6, tumour necrosis factor alpha and monocyte chemotactic protein 1 and vascular endothelial growth factor in hyperstimulated rats. The results indicate that electroacupuncture can modulate endocrine hormone secretion and affect the secretion of inflammatory cytokines and vascular endothelial growth factor, and thus prevent the progress of OHSS. Electroacupuncture may provide a simple and effective method for the prevention and treatment of OHSS.

Prevention of ovarian hyperstimulation syndrome in a rat model: comparison of the efficacy of tocilizumab with that of ranibizumab, cabergoline, and a gonadotropin-releasing hormone antagonist

The aim of the study is to investigate the effects of the interleukin-6 (IL-6) blocker tocilizumab in a hyperstimulated rat model and compare it with ranibizumab, a gonadotropin-releasing hormone antagonist (GnRHA), and cabergoline. Forty-seven rats were randomly divided into the following seven groups: Group 1: OHS; Group 2: OHS+ GnRHA; Group 3: OHS + ranibizumab; Group 4: OHS + cabergoline; Group 5: OHS + low-dose tocilizumab (TL); Group 6: OHS + high-dose tocilizumab (TH); Group 7: sham. Ovarian weight was significantly lower only in the ranibizumab group than in the OHS group. Estrogen levels were significantly lower in the GnRHA group than in the OHS and the treatment groups. Progesterone levels were significantly lower in the ranibizumab, cabergoline, and TL groups than in the OHS group. Among the treatment groups, corpus luteum counts were lower than in the OHS group. Corpus luteum counts were lowest in the tocilizumab groups. IL-6 intensity was lower in all treatment groups than in the OHS group. In the ranibizumab group IL-6 intensity was the lowest. The TL group did not significantly differ from the GnRHA and cabergoline groups regarding IL-6 expression. Ovarian VEGF expression was significantly lower in all treatment groups. For the TL, ranibizumab, and cabergoline groups VEGF intensity was similar. Tocilizumab may be a new strategy for preventing ovarian hyperstimulation syndrome by inhibition of IL-6.

The time interval between hCG priming and oocyte retrieval in ART program: a meta-analysis

OBJECTIVE

To evaluate the relationship between different hCG priming-to-oocyte retrieval intervals and assisted reproductive technology (ART) outcome.

METHODS

We systematically searched PubMed, EMBASE, the Cochrane Library, Science Citation Index, Chinese biomedicine (CBM) literature database, and Chinese Journal Full-text Database for randomized controlled trials (RCTs) published up to November 2010. Data was extracted from the studies by two independent reviewers. Statistical analysis was performed with Cochrane Collaboration's Review Manager (RevMan) 5.0.2. From extracted data, Risk Ratio (RR) with 95% confidence interval (CI) was calculated.

RESULTS

5 RCTs totaling 895 participants were included. Oocyte maturation rate was higher in the long interval group compared with short interval group (RR, 0.67; 95% CI, 0.62-0.73). There were no significant difference between the two groups with regard to fertilization rate (RR, 0.99; 95% CI, 0.94-1.04), implantation rate (RR, 0.91; 95% CI, 0.40-2.04), and pregnancy rate (RR, 0.79; 95% CI, 0.58-1.08).

CONCLUSION

The percentage of mature (MII) oocytes can be increased by prolonging the interval between hCG priming and oocyte retrieval. The prolonged interval could not increase the fertilization rate, implantation rate, and pregnancy rate. Although there was evidence to confirm the results, they still need to be confirmed by large-sample, multicenter, randomized controlled trials. The time interval dependent mechanisms responsible for ART performance need to be elucidated.

Low follicular fluid IL-6 levels in IVF patients are associated with increased likelihood of clinical pregnancy

PURPOSE

Relationships between follicular fluid levels of IL-6 with ovarian response and clinical pregnancy were evaluated in IVF-ET cycles.

METHODS

Follicular fluid was collected from ovarian follicles ≥ 14 mm, pooled for each patient, and IL-6 levels were assessed using ELISA (n = 68). Relationships between IL-6 levels and IVF cycle parameters were assessed using nonparametric tests, and between IL-6 levels and clinical pregnancy using multivariable logistic regression analyses.

RESULTS

Significant positive correlations were observed between IL-6 with age (p = 0.035), and IL-6 with estradiol on the day of hCG (p = 0.011). On adjusted analyses, IVF cycles in patients with IL-6 levels <4.0 pg/ml (median value for the group) demonstrated an almost 4-fold increase in likelihood for clinical pregnancy (p = 0.045).

CONCLUSIONS

Lower follicular fluid IL-6 levels in IVF patients are associated with increased likelihood of clinical pregnancy. We hypothesize that endometrial receptivity is a likely target for any deleterious influences of elevated IL-6 levels.

Continuous vaginal and bilateral thoracic fluid drainage for management of severe ovarian hyperstimulation syndrome

Severe ovarian hyperstimulation syndrome (OHSS) is a serious and potentially fatal complication of ovarian stimulation. A 29-year-old nulligravid patient with anovulatory infertility was treated with in vitro fertilization. Six days after embryo transfer, the patient presented with complaint of abdominal bloating, nausea, vomiting and shortness of breath. Severe late-onset OHSS, with massive ascites and pleural effusion, was diagnosed. Posterior colpotomy was performed under general anesthesia, a Foley catheter was inserted into the posterior cul-de-sac, and bilateral chest drainage tubes were left for continuous drainage. In total, 13.2 liters of ascites and 6.1 liters of pleural fluid were drained in 8 days. Continuous drainage of ascites and pleural effusion improved the patient's comfort without need for repeated transvaginal and thoracic aspirations.

Low-dose HCG is useful in preventing OHSS in high-risk women without adversely affecting the outcome of IVF cycles

Severe ovarian hyperstimulation syndrome (OHSS) is a rare but potentially fatal condition associated with conventional IVF treatment. It is found predominantly in women with polycystic ovaries who have an exaggerated response to exogenous FSH, leading to a large number of follicles and an overproduction of vascular endothelial growth factor with resultant excessive increases in vascular permeability. There is evidence to suggest that OHSS is also linked to the use of human chorionic gonadotrophin (HCG) to induce ovulation. Therefore, while HCG is essential for corpus luteum function, high amounts of HCG can lead to OHSS in high responders. In a pilot study, infertile patients at high risk of developing OHSS were given half the current minimum dose of HCG (i.e. 2500 IU). No woman developed moderate or severe OHSS; 13 women (61.9%) conceived and there were three twin pregnancies. In women at high risk of OHSS, a low dose of HCG appears to prevent the development of OHSS without compromising success rates.

Vascular endothelial growth factor levels in serum and plasma from patients undergoing controlled ovarian hyperstimulation for IVF

BACKGROUND

Vascular endothelial growth factor (VEGF) has been investigated as a marker of ovarian response to controlled ovarian hyperstimulation and as a predictor of ovarian hyperstimulation syndrome (OHSS) in IVF cycles. In most studies, serum has been used for circulating VEGF concentration measurement, but it has been suggested that plasma is the preferred medium to measure VEGF levels because of the potential contribution of VEGF released from platelets during blood clotting. This study investigated VEGF concentrations in paired serum and plasma samples from patients undergoing controlled ovarian hyperstimulation for IVF.

METHODS

Serum and plasma VEGF levels, as well as the number of platelets, were measured in 30 IVF patients who comprised three study groups delineated according to the estradiol (E(2)) serum concentration reached on the day of HCG administration: 10 patients having low E(2) serum levels (<1500 pg/ml, group L), 10 patients having intermediate E(2) serum levels (1500-3000 pg/ml, group I) and 10 patients having high E(2) serum levels (>3000 pg/ml, group H).

RESULTS

There was a statistically significant correlation between plasma and serum VEGF levels (rho = 0.61; P < 0.005) for the entire population studied, although serum values were higher by a factor of approximately 6-fold. No significant correlation was found between peripheral blood VEGF concentrations and serum E(2) or follicle number on HCG day or the number of oocytes collected. Similarly, paired serum and plasma VEGF measurements did not correlate with platelet count.

CONCLUSIONS

Serum and plasma VEGF concentrations are strongly correlated in paired samples from infertile patients undergoing controlled ovarian hyperstimulation. However, neither serum nor plasma VEGF levels were correlated with parameters associated with ovarian follicular activity. Peripheral blood VEGF levels were not correlated with platelet count.

Angiogenic activity of human chorionic gonadotropin through LH receptor activation on endothelial and epithelial cells of the endometrium

Successful embryo development requires an extensive endometrial angiogenesis in proximity of implantation site. The glycoprotein hCG is produced even before implantation by trophoblast in normal pregnancy. In this manuscript, we demonstrate an angiogenic effect of hCG in several in vivo (chick chorioallantoïc membrane, matrigel plug assay, aortic ring assay) and in vitro experimental models. In contrast, human placental lactogen (hPL) did not display angiogenic properties. LH/hCG receptor was detected in endothelial cells by reverse-transcriptase polymerase chain reaction (RT-PCR) and by Western blotting. In mice aortic ring assay, angiostimulation by hCG was abrogated by deletion of LH/hCG receptor (LuRKO mice). Use of recombinant hCG and anti-hCG antibody (Ab) further confirmed the specificity of this angiogenic activity. By using dibutyryl cAMP, adenylate cyclase, or protein kinase A inhibitors, we demonstrate that hCG-mediated angiogenesis involves adenylyl-cyclase-protein kinase A activation. Addition of hCG to endometrial epithelial epithelial cells, but not to cultured endothelial cells, stimulated vascular endothelial growth factor (VEGF). VEGF and hCG also displayed additive activities. Altogether, these data demonstrate that peritrophoblastic angiostimulation may result from a paracrine dialogue between trophoblast, epithelial, and endothelial cells through hCG and VEGF.

Serum leptin concentrations in patients with severe ovarian hyperstimulation syndrome during in vitro fertilization–embryo transfer treatment

OBJECTIVE

To investigate the changes in serum leptin concentration in the conception cycle of severe ovarian hyperstimulation syndrome (OHSS).

DESIGN

Prospective longitudinal study of 66 IVF-ET cycles between May 2000 and June 2002.

SETTING

Infertility outpatient clinic at a Japanese medical school.

PATIENT(S)

Infertile patients undergoing IVF-ET cycles at the infertility outpatient clinic were divided into three groups consisting of group 1 (conception-cycle patients with severe OHSS, n = 9), and group 2 (conception cycle, non-OHSS, n = 28), and group 3 (nonconception cycle, non-OHSS, n = 29).

INTERVENTION(S)

Blood samples were collected at five different periods. Period I, on the first day of ovarian stimulation with FSH; period II, at hCG administration before oocyte retrieval; period III, 7 days after oocyte retrieval; period IV, 14 days after oocyte retrieval; and period V, 21 days after oocyte retrieval.

MAIN OUTCOME MEASURE(S)

Serum leptin concentration.

RESULT(S)

The serum leptin concentration was low in the OHSS group compared with that of the non-OHSS groups in all serum samples, with significant levels at periods III (vs. groups 2 and 3; P<.05) and IV (vs. group 3; P<.01). A twofold increase of leptin concentration from period I to period II (P<.05) was observed in all groups.

CONCLUSION(S)

The change pattern in serum leptin concentration might provide a great contribution to the pathophysiology development of OHSS patients during assisted reproductive treatment.