Annemieke Hoek

Characterization of the Human Visceral Adipose Tissue Secretome

Adipose tissue is an endocrine organ involved in storage and release of energy but also in regulation of energy metabolism in other organs via secretion of peptide and protein hormones (adipokines). Especially visceral adipose tissue has been implicated in the development of metabolic syndrome and type 2 diabetes. Factors secreted by the stromal-vascular fraction contribute to the secretome and modulate adipokine secretion by adipocytes. Therefore, we aimed at the characterization of the adipose tissue secretome rather than the adipocyte cell secretome. The presence of serum proteins and intracellular proteins from damaged cells, released during culture, may dramatically influence the dynamic range of the sample and thereby identification of secreted proteins. Part of the study was therefore dedicated to the influence of the culture setup on the quality of the final sample. Visceral adipose tissue was cultured in five experimental setups, and the quality of resulting samples was evaluated in terms of protein concentration and protein composition. The best setup involved one wash after the 1st h in culture followed by two or three additional washes within an 8-h period, starting after overnight culture. Thereafter tissue was maintained in culture for an additional 48–114 h to obtain the final sample. For the secretome experiment, explants were cultured in media containing l-[13C6,15N2]lysine to validate the origin of the identified proteins (adipose tissue- or serum-derived). In total, 259 proteins were identified with ≥99% confidence. 108 proteins contained a secretion signal peptide of which 70 incorporated the label and were considered secreted by adipose tissue. These proteins were classified into five categories according to function. This is the first study on the (human) adipose tissue secretome. The results of this study contribute to a better understanding of the role of adipose tissue in whole body energy metabolism and related diseases.

Anti-Müllerian Hormone, Inhibin B, and Antral Follicle Count in Young Women with Ovarian Failure

CONTEXT Ovarian dysfunction is classically categorized on the basis of cycle history, FSH, and estradiol levels. Novel ovarian markers may provide a more direct insight into follicular quantity in hypergonadotropic women. OBJECTIVE The objective of the study was to investigate the distribution of novel ovarian markers in young hypergonadotropic women as compared with normogonadotropic regularly menstruating women. DESIGN This was a nationwide prospective cohort study. SETTING The study was conducted at 10 hospitals in The Netherlands. PATIENTS Women below age 40 yr with regular menses and normal FSH (controls; n = 83), regular menstrual cycles and elevated FSH [incipient ovarian failure (IOF); n = 68]; oligomenorrhea and elevated FSH [referred to as transitional ovarian failure (TOF); n = 79]; or at least 4 months amenorrhea together with FSH levels exceeding 40 IU/liter [premature ovarian failure (POF); n = 112]. MAIN OUTCOME MEASURES Serum levels of anti-Müllerian hormone (AMH), inhibin B, and antral follicle count (AFC) was measured. RESULTS All POF patients showed AMH levels below the fifth percentile (p(5)) of normoovulatory women. Normal AMH levels (>p(5)) could be identified in 75% of IOF, 33% of TOF patients, and 98% of controls. AFC and AMH levels changed with increasing age (P < 0.0001), whereas inhibin B did not (P = 0.26). AMH levels were significantly different between TOF and IOF over the entire age range, whereas AFC became similar for TOF and IOF at higher ages. CONCLUSIONS Compared with inhibin B and AFC, AMH was more consistently correlated with the clinical degree of follicle pool depletion in young women presenting with elevated FSH levels. AMH may provide a more accurate assessment of the follicle pool in young hypergonadotropic patients, especially in the clinically challenging subgroups of patients with elevated FSH and regular menses (i.e. IOF) and in hypergonadotropic women with cycle disturbances not fulfilling the POF diagnostic criteria (i.e. TOF).

Regulation of adipokine production in human adipose tissue by propionic acid

Eur J Clin Invest 2010; 40 (5): 401–407

Insulin sensitizing drugs for weight loss in women of reproductive age who are overweight or obese: systematic review and meta-analysis

BACKGROUND Women of reproductive age, who are overweight or obese, are prone to infertility. Weight loss in these women leads to increased fecundity, higher chances of conception after infertility treatment and improved pregnancy outcome. In spite of the advantages, most patients have difficulty in losing weight and often regain lost weight over time. This review assesses whether treatment with insulin sensitizing drugs contributes to weight loss, compared with diet or a lifestyle modification programme. METHODS After a systematic search of the literature, only randomized controlled trials (RCTs), investigating the effect of insulin sensitizing drugs on weight loss compared with placebo and diet and/or a lifestyle modification programme, were included. Subjects were restricted to women of reproductive age. The main outcome measure was change in body mass index (BMI). RESULTS Only 14 trials, unintentionally all but two on women with polycystic ovary syndrome (PCOS) only, were included in the analysis. Treatment with metformin showed a statistically significant decrease in BMI compared with placebo (weighted mean difference, -0.68; 95% CI -1.13 to -0.24). There was some indication of greater effect with high-dose metformin (>1500 mg/day) and longer duration of therapy (>8 weeks). Limitations were power, low use of intention-to-treat analysis and heterogeneity of the studies. CONCLUSION A structured lifestyle modification programme to achieve weight loss should still be the first line treatment in obese women with or without PCOS. Adequately powered RCTs are required to confirm the findings of this review and to assess whether the addition of high-dose metformin therapy to a structured lifestyle modification programme might contribute to more weight loss.

Decreased androgen concentrations and diminished general and sexual well-being in women with premature ovarian failure

Objective: To describe general and sexual well-being in women with premature ovarian failure (POF) and to investigate whether there is a relationship between androgen levels and sexual functioning. Design: Women with POF and healthy volunteers with regular menstrual cycles participated. Participants completed a written questionnaire and underwent hormonal screening. The questionnaire included standardized measures: the Questionnaire for Screening Sexual Dysfunctions, the Shortened Fatigue Questionnaire, and the Symptom Check List-90. Serum hormone measurements included estradiol, total testosterone, bioavailable testosterone, androstenedione, dehydroepiandrosterone, and dehydroepiandrosterone sulfate. Results: Eighty-one women with POF and 68 control women participated in the study. Compared with control women, women with POF reported more complaints of anxiety, depression, somatization, sensitivity, hostility, and psychological distress. Overall women with POF were less satisfied with their sexual life. They had fewer sexual fantasies and masturbated less frequently. Sexual contact was associated with less sexual arousal, reduced lubrication, and increased genital pain. However, the frequency of desire to have sexual contact and the frequency of actual sexual contact with the partner did not differ between women with POF and control women. Women with POF had lower levels of estradiol, total testosterone, and androstenedione. Multiple regression analysis revealed that androgen levels had only a weak influence on sexual functioning; higher total testosterone levels were associated with increased frequency of desire for sexual contact, and higher androstenedione levels were associated with elevated frequency of sexual contact. Conclusions: Women with POF have diminished general and sexual well-being and are less satisfied with their sexual lives than control women. Although women with POF had lower androgen levels, we did not find an important independent role for androgens in various aspects of sexual functioning.

Genome-wide association study in premature ovarian failure patients suggests ADAMTS19 as a possible candidate gene

BACKGROUND Spontaneous premature ovarian failure (POF) occurs in 1% of women and has major implications for their fertility and health. Besides X chromosomal aberrations and fragile X premutations, no common genetic risk factor has so far been discovered in POF. Using high-density single nucleotide polymorphism (SNP) arrays, we set out to identify new genetic variants involved in this condition. METHODS A genome-wide association study involving 309 158 SNPs was performed in 99 unrelated idiopathic Caucasian POF patients and 235 unrelated Caucasian female controls. A replication study on the most significant finding was performed. We specifically focused on chromosomal areas and candidate genes previously implicated in POF. RESULTS Suggestive genome-wide significant association was observed for rs246246 (allele frequency P = 6.0 x 10(-7)) which mapped to an intron of ADAMTS19, a gene known to be up-regulated in the female mouse gonads during sexual differentiation. However, replication in an independent Dutch cohort (60 POF patients and 90 controls) could not confirm a clear association (P = 4.1 x 10(-5) in a joint analysis). We did not observe strong evidence for any of 74 selected POF candidate genes or linkage regions being associated with idiopathic POF in Caucasian females, although suggestive association (P < 0.005) was observed for SNPs that mapped in BDNF, CXCL12, LHR, USP9X and TAF4B. CONCLUSION We observed a possible association between POF and a SNP in a biologically plausible candidate gene. Although limited by sample size, this proof-of-principle studys findings reveal ADAMTS19 as a possible candidate gene for POF and thus a larger follow-up study is warranted.

Propionic acid affects immune status and metabolism in adipose tissue from overweight subjects

Eur J Clin Invest 2012; 42 (4): 357–364

PREDICTIVE VALUE OF BASAL FOLLICLE-STIMULATING HORMONE CONCENTRATIONS IN A GENERAL SUBFERTILITY POPULATION

OBJECTIVE To assess the predictive value of elevated basal FSH concentrations during the initial subfertility workup with respect to fecundity in a general subfertility population with ovulatory menstrual cycles. DESIGN Nested case-control study. SETTING Fertility center of a university hospital. PATIENT(S) Fifty subfertile women with basal FSH levels >10.0 IU/L and 50 age-matched controls. INTERVENTION(S) Long-term follow-up (3-7 years). MAIN OUTCOME MEASURE(S) Pregnancies, deliveries, and time to pregnancy. RESULT(S) Patients with elevated basal FSH levels and controls were comparable with regard to basic characteristics, clinical diagnoses, and subfertility treatment. Long-term follow-up showed that 52% of the women with elevated basal FSH concentrations became pregnant (positive predictive value 48%) versus 62% of the controls, and 42% versus 46% eventually delivered a child, respectively. The mean time to pregnancy was 3.0 years in the elevated-FSH group and 3.4 years in controls. Most of the pregnancies in both groups occurred after spontaneous conceptions. CONCLUSION(S) The results of this study suggest that screening for elevated basal FSH concentrations is of no additional value in a general subfertility population with ovulatory menstrual cycles.

A Randomized Trial of Progesterone in Women with Recurrent Miscarriages

BACKGROUND Progesterone is essential for the maintenance of pregnancy. However, whether progesterone supplementation in the first trimester of pregnancy would increase the rate of live births among women with a history of unexplained recurrent miscarriages is uncertain. METHODS We conducted a multicenter, double-blind, placebo-controlled, randomized trial to investigate whether treatment with progesterone would increase the rates of live births and newborn survival among women with unexplained recurrent miscarriage. We randomly assigned women with recurrent miscarriages to receive twice-daily vaginal suppositories containing either 400 mg of micronized progesterone or matched placebo from a time soon after a positive urinary pregnancy test (and no later than 6 weeks of gestation) through 12 weeks of gestation. The primary outcome was live birth after 24 weeks of gestation. RESULTS A total of 1568 women were assessed for eligibility, and 836 of these women who conceived naturally within 1 year and remained willing to participate in the trial were randomly assigned to receive either progesterone (404 women) or placebo (432 women). The follow-up rate for the primary outcome was 98.8% (826 of 836 women). In an intention-to-treat analysis, the rate of live births was 65.8% (262 of 398 women) in the progesterone group and 63.3% (271 of 428 women) in the placebo group (relative rate, 1.04; 95% confidence interval [CI], 0.94 to 1.15; rate difference, 2.5 percentage points; 95% CI, -4.0 to 9.0). There were no significant between-group differences in the rate of adverse events. CONCLUSIONS Progesterone therapy in the first trimester of pregnancy did not result in a significantly higher rate of live births among women with a history of unexplained recurrent miscarriages. (Funded by the United Kingdom National Institute of Health Research; PROMISE Current Controlled Trials number, ISRCTN92644181.).

Salpingotomy versus salpingectomy in women with tubal pregnancy (ESEP study): an open-label, multicentre, randomised controlled trial.

BACKGROUND Tubal ectopic pregnancy can be surgically treated by salpingectomy, in which the affected Fallopian tube is removed, or salpingotomy, in which the tube is preserved. Despite potentially increased risks of persistent trophoblast and repeat ectopic pregnancy, salpingotomy is often preferred over salpingectomy because the preservation of both tubes is assumed to offer favourable fertility prospects, although little evidence exists to support this assumption. We aimed to assess whether salpingotomy would improve rates of ongoing pregnancy by natural conception compared with salpingectomy. METHODS In this open-label, multicentre, international, randomised controlled trial, women aged 18 years and older with a laparoscopically confirmed tubal pregnancy and a healthy contralateral tube were randomly assigned via a central internet-based randomisation program to receive salpingotomy or salpingectomy. The primary outcome was ongoing pregnancy by natural conception. Differences in cumulative ongoing pregnancy rates were expressed as a fecundity rate ratio with 95% CI, calculated by Cox proportional-hazards analysis with a time horizon of 36 months. Secondary outcomes were persistent trophoblast and repeat ectopic pregnancy (expressed as relative risks [RRs] with 95% CIs) and ongoing pregnancy after ovulation induction, intrauterine insemination, or IVF. The researchers who collected data for fertility outcomes were masked to the assigned intervention, but patients and the investigators who analysed the data were not. All endpoints were analysed by intention to treat. We also did a (non-prespecified) meta-analysis that included the findings from the present trial. This trial is registered, number ISRCTN37002267. FINDINGS 446 women were randomly assigned between Sept 24, 2004, and Nov 29, 2011, with 215 allocated to salpingotomy and 231 to salpingectomy. Follow-up was discontinued on Feb 1, 2013. The cumulative ongoing pregnancy rate was 60·7% after salpingotomy and 56·2% after salpingectomy (fecundity rate ratio 1·06, 95% CI 0·81-1·38; log-rank p=0·678). Persistent trophoblast occurred more frequently in the salpingotomy group than in the salpingectomy group (14 [7%] vs 1 [<1%]; RR 15·0, 2·0-113·4). Repeat ectopic pregnancy occurred in 18 women (8%) in the salpingotomy group and 12 (5%) women in the salpingectomy group (RR 1·6, 0·8-3·3). The number of ongoing pregnancies after ovulation induction, intrauterine insemination, or IVF did not differ significantly between the groups. 43 (20%) women in the salpingotomy group were converted to salpingectomy during the initial surgery because of persistent tubal bleeding. Our meta-analysis, which included our own results and those of one other study, substantiated the results of the trial. INTERPRETATION In women with a tubal pregnancy and a healthy contralateral tube, salpingotomy does not significantly improve fertility prospects compared with salpingectomy. FUNDING Netherlands Organisation for Health Research and Development (ZonMW), Region Västra Götaland Health & Medical Care Committee.