Improved clinical utility of preimplantation genetic testing through the integration of ploidy and common pathogenic microdeletions analyses

STUDY QUESTION

Can chromosomal abnormalities beyond copy-number aneuploidies (i.e. ploidy level and microdeletions (MDs)) be detected using a preimplantation genetic testing (PGT) platform?

SUMMARY ANSWER

The proposed integrated approach accurately assesses ploidy level and the most common pathogenic microdeletions causative of genomic disorders, expanding the clinical utility of PGT.

WHAT IS KNOWN ALREADY

Standard methodologies employed in preimplantation genetic testing for aneuploidy (PGT-A) identify chromosomal aneuploidies but cannot determine ploidy level nor the presence of recurrent pathogenic MDs responsible for genomic disorders. Transferring embryos carrying these abnormalities can result in miscarriage, molar pregnancy, and intellectual disabilities and developmental delay in offspring. The development of a testing strategy that integrates their assessment can resolve current limitations and add valuable information regarding the genetic constitution of embryos, which is not evaluated in PGT providing new level of clinical utility and valuable knowledge for further understanding of the genomic causes of implantation failure and early pregnancy loss. To the best of our knowledge, MDs have never been studied in preimplantation human embryos up to date.

STUDY DESIGN, SIZE, DURATION

This is a retrospective cohort analysis including blastocyst biopsies collected between February 2018 and November 2021 at multiple collaborating IVF clinics from prospective parents of European ancestry below the age of 45, using autologous gametes and undergoing ICSI for all oocytes. Ploidy level determination was validated using 164 embryonic samples of known ploidy status (147 diploids, 9 triploids, and 8 haploids). Detection of nine common MD syndromes (-4p=Wolf-Hirschhorn, -8q=Langer-Giedion, -1p=1p36 deletion, -22q=DiGeorge, -5p=Cri-du-Chat, -15q=Prader-Willi/Angelman, -11q=Jacobsen, -17p=Smith-Magenis) was developed and tested using 28 positive controls and 97 negative controls. Later, the methodology was blindly applied in the analysis of: (i) 100 two pronuclei (2PN)-derived blastocysts that were previously defined as uniformly euploid by standard PGT-A; (ii) 99 euploid embryos whose transfer resulted in pregnancy loss.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The methodology is based on targeted next-generation sequencing of selected polymorphisms across the genome and enriched within critical regions of included MD syndromes. Sequencing data (i.e. allelic frequencies) were analyzed by a probabilistic model which estimated the likelihood of ploidy level and MD presence, accounting for both sequencing noise and population genetics patterns (i.e. linkage disequilibrium, LD, correlations) observed in 2504 whole-genome sequencing data from the 1000 Genome Project database. Analysis of phased parental haplotypes obtained by single-nucleotide polymorphism (SNP)-array genotyping was performed to confirm the presence of MD.

MAIN RESULTS AND THE ROLE OF CHANCE

In the analytical validation phase, this strategy showed extremely high accuracy both in ploidy classification (100%, CI: 98.1-100%) and in the identification of six out of eight MDs (99.2%, CI: 98.5-99.8%). To improve MD detection based on loss of heterozygosity (LOH), common haploblocks were analyzed based on haplotype frequency and LOH occurrence in a reference population, thus developing two further mathematical models. As a result, chr1p36 and chr4p16.3 regions were excluded from MD identification due to their poor reliability, whilst a clinical workflow which incorporated parental DNA information was developed to enhance the identification of MDs. During the clinical application phase, one case of triploidy was detected among 2PN-derived blastocysts (i) and one pathogenic MD (-22q11.21) was retrospectively identified among the biopsy specimens of transferred embryos that resulted in miscarriage (ii). For the latter case, family-based analysis revealed the same MD in different sibling embryos (n = 2/5) from non-carrier parents, suggesting the presence of germline mosaicism in the female partner. When embryos are selected for transfer based on their genetic constitution, this strategy can identify embryos with ploidy abnormalities and/or MDs beyond aneuploidies, with an estimated incidence of 1.5% (n = 3/202, 95% CI: 0.5-4.5%) among euploid embryos.

LIMITATIONS, REASONS FOR CAUTION

Epidemiological studies will be required to accurately assess the incidence of ploidy alterations and MDs in preimplantation embryos and particularly in euploid miscarriages. Despite the high accuracy of the assay developed, the use of parental DNA to support diagnostic calling can further increase the precision of the assay.

WIDER IMPLICATIONS OF THE FINDINGS

This novel assay significantly expands the clinical utility of PGT-A by integrating the most common pathogenic MDs (both de novo and inherited ones) responsible for genomic disorders, which are usually evaluated at a later stage through invasive prenatal testing. From a basic research standpoint, this approach will help to elucidate fundamental biological and clinical questions related to the genetics of implantation failure and pregnancy loss of otherwise euploid embryos.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was used for this study. S.C., M.F., F.C., P.Z., I.P., L.G., C.P., M.P., D.B., J.J.-A., D.B.-J., J.M.-V., and C.R. are employees of Igenomix and C.S. is the head of the scientific board of Igenomix. A.C. and L.P. are employees of JUNO GENETICS. Igenomix and JUNO GENETICS are companies providing reproductive genetic services.

TRIAL REGISTRATION NUMBER

N/A.

P-555 Improved clinical validity of Preimplantation Genetic Testing for Aneuploidy (PGT-A) using a next-generation sequencing workflow for simultaneous detection of aneuploidy, ploidy and common pathogenic microdeletions

Study question

Can chromosomal abnormalities beyond aneuploidies (i.e., ploidy and microdeletions, MD) be detected on a single trophectoderm (TE) embryo biopsy using a next-generation sequencing (NGS)-based workflow?

Summary answer

This NGS-based integrated approach allows accurate detection of ploidy status and the most common microdeletions from a single TE-biopsy,expanding PGT-A clinical validity and diagnostic capabilities.

What is known already

Standard methodologies employed in PGT-A do not determine embryo ploidy status due to the normalization process during copy-number-variation analysis. Transferring embryos with abnormal ploidy variations is expected to result in miscarriage or molar pregnancy. Common pathogenic MD are undetected as they fall below the PGT-A resolution limit (<10Mb). MD are involved in genomic disorders associated with neurodevelopmental disabilities and multiple congenital anomalies. The development of this sequencing strategy can resolve current limitations and add valuable information regarding the genetic constitution of embryos, which is not usually evaluated in PGT and normally requires the use of later-stage invasive prenatal diagnosis.

Study design, size, duration

Ploidy determination was validated using 244 embryo samples of known ploidy status (226 diploids, 10 triploids, 8 haploids). We analysed nine common MD syndromes (-4p=Wolf-Hirschhorn, -8q=Langer-Giedion, -1p=1p36 deletion, -22q=DiGeorge, -5p=Cri-du-Chat, -15q=Prader-Willi/Angelman, -11q=Jacobsen, -17p=Smith-Magenis) using 24 positive controls (amniocentesis DNA from MD cases or TE biopsies from autosomal monosomy mimicking MD) and 96 negative controls (healthy newborns). Overall, the dataset included 72 cases of individual chromosomal abnormalities and 576 negative cases across the eight MD regions.

Participants/materials, setting, methods

PGT-A products were reamplified and sequenced (IonTorrentS5-ThermoFisher) using a custom AmpliSeq panel targeting 384 regions with at least one Single Nucleotide Polymorphism (SNP) of high B-allelic frequency. A bioinformatic algorithm based on gaussian-mixture modelling of sequencing data was developed. This algorithm calculates the conditional probability of the observed B-allelic ratio for each SNP, depending on the copy number, then estimates the likelihood of ploidy and the presence of MD based on the sequencing outcomes.

Main results and the role of chance

Ploidy was correctly determined in 233/234 cases (Accuracy=99.4%), with only one diploid sample misclassified as triploid (PPV=94.1%, NPV=100%, Non-informative rate=9/243=3.1%).

Microdeletions could be consistently detected with high reliability in 6 out of the 8 considered regions (-8q,-22q,-5p,-15q,-11q and -17p; PPV=98.5%, NPV=99.5%). Detection of microdeletions of 1p and 4p were less reliable due to the presence of recurrent haplotype blocks in the population at those genomic regions, as confirmed by the analysis of a dataset of 2504 whole genome sequencing from One Thousand Genome Project database (1kGP). The only MD false positive case showed extended loss of heterozygosity in the microdeletion region (-22q), which might be related to uniparental disomy or consanguinity and requires further testing in the family.

This analytical framework was blindly applied to: (i) the analysis of 9 embryos from a family affected by DiGeorge syndrome (female partner was carrier of del22.q11.21(20754422-21440514), resulting in all embryos classified consistently with the conventional PGT-M results (using indirect linkage analysis); (ii) the analysis of samples from 99 transferred human euploid embryos resulting in pregnancy losses. No ploidy alteration was detected in miscarried euploid embryos, but 2 microdeletions (-8q, -22q) were found, with an estimated prevalence of 2/99 in the miscarriage population.

Limitations, reasons for caution

Larger cohort studies will be required to accurately assess the incidence of ploidy alterations and microdeletions in preimplantation embryos and particularly in euploid miscarriages. Despite the high accuracy of the assay developed, the use of parental DNA to support diagnostic calling can further increase the precision of the assay.

Wider implications of the findings

This study provides, for the first time, detection of common pathogenic microdeletions and ploidy status from a single TE biopsy, expanding PGT-A clinical validity. This new assay will also help elucidate fundamental biological and clinical questions related to the genetics of implantation failure and pregnancy loss of apparently euploid embryos.

Trial registration number

not applicable

Diagnostic accuracy of sonohysterography and transvaginal sonography as compared with hysteroscopy and endometrial biopsy: a prospective study

AIM

The aim of the study was to compare the diagnostic accuracy between transvaginal sonography (TVS) and sonohysterography (SHG) versus hysteroscopy (Hys) plus endometrial biopsy (EB) to evaluate uterine cavity.

METHODS

One hundred and sixteen patients were enrolled. These presented with infertility and/or abnormal uterine bleeding and/or suspicious uterine cavity pathology. Women consecutively underwent during the same day, to TVS, SHG and Hys plus EB by three different operators.

RESULTS

TVS shows excellent specificity (95.7%) in uterine polyps detection, good sensitivity (85,7%) and specificity (89.2%) in investigating endometrial hyperplasia, and excellent NPV (92.2%) in the diagnosis of submucous myomas. Diagnostic accuracy of TVS for synechiae is not evaluable. SHG demonstrates high specificity (92.8%) in the detection of uterine polyps, and high sensitivity (92.9%) and specificity (96.8%) in the diagnosis of endometrial hyperplasia. In addition it shows high sensitivity (90%), specificity (99%), PPV (92.2%), and NPV (99%) for detection of submucous myomas. Finally, SHG shows high PPV (100%) and NPV (100%) for synechiae assessment.

CONCLUSION

TVS could be used as first step investigation to exclude uterine pathologies. TVS could reduce the number of diagnostic Hys normally performed in women with normal uterine cavity. Furthermore SHG should be useful to diagnose the pathologies and to decide between operative Hys in-office or resectoscopic treatment.

Lower embryonic loss rates among twin gestations following assisted reproduction

PURPOSE

To determine whether maternal age and number of transferred embryos influence early pregnancy losses in twin pregnancies compared to singletons following IVF/ICSI.

METHODS

We compared the pregnancy loss rates in singleton (n = 549) and twin (n = 252) gestations, stratified by maternal age (< or = 35 and > 35 years) and the number of transferred embryos (1-3 and 4-9).

RESULTS

Loss rates of singleton pregnancies were significantly higher than that in twins (OR 3.0, 95% CI 1.9, 4.9), especially among singletons conceived after transfer of 4-9 embryos (OR 5.0, 95% CI 2.2, 11.9). Younger mothers of twins had lower loss rates (OR 0.3, 95% CI 0.1, 0.9).

CONCLUSION

Twins have a significantly reduced spontaneous miscarriage rate compared with singletons following IVF/ICSI. Higher implantation rates per cycle (i.e., development of twins rather than one live embryo) may represent a better capacity of the uterus for early embryonic development.

Different concentrations of interleukins in the peritoneal fluid of women with endometriosis: relationships with lymphocyte subsets

The present study explored the possible relationships between immune cell subsets and interleukin (IL)-12 or IL-13 levels in the peritoneal fluid of patients with and without endometriosis. Peritoneal fluid samples were obtained from 80 women while they were undergoing laparoscopy for pain, infertility, tubal ligation or re-anastomosis. The American Fertility Society scoring system was used to determine the extension of endometriosis. The peritoneal fluid mononuclear cells were analyzed for immunophenotyping using cytometry, whereas peritoneal fluid concentrations of interleukins were measured using two ultrasensitive commercially available enzyme-linked imnunosorbent assay kits. Significantly higher peritoneal fluid IL-12 levels were found in women with moderate or severe endometriosis (stages III and IV) than in healthy controls (p < 0.01). Conversely, subjects with endometriosis showed remarkably lower peritoneal fluid IL-13 concentrations than controls, independent of the severity of the disease (p < 0.05). Considering immune system effectors, patients with endometriosis presented a significantly higher peritoneal fluid CD8+/CD4+ ratio when compared with healthy controls. Moreover, the number of peritoneal fluid CD8+ and CD4+ activated T cells was significantly lower in the former than in the latter group, independent of the endometriosis stage. Connections were observed between peritoneal fluid interleukins and peritoneal fluid T cells: both patients with endometriosis and controls presented an inverse correlation between peritoneal fluid activated T cells and IL-13 levels, and a direct correlation between peritoneal fluid T cells and IL-12 concentrations. These data seem to suggest that a reciprocal modulation exists between peritoneal fluid cytokines and T lymphocyte subsets in patients with endometriosis.

Immunological changes and stress are associated with different implantation rates in patients undergoing in vitro fertilization-embryo transfer

OBJECTIVE

To evaluate the possible correlation between immunological changes and implantation rates in patients who undergo in vitro fertilization-embryo transfer (IVF-ET).

DESIGN

Controlled clinical study.

SETTING

University hospital.

PATIENT(S)

Forty infertile women undergoing IVF-ET.

INTERVENTION(S)

Stroop Color Word (CW) test, State-Trait Anxiety Inventory (STAI) test, blood sampling.

MAIN OUTCOME MEASURE(S)

Heart rate and systolic and diastolic blood pressure responses to Stroop CW; circulating T, B, T-helper (CD4), and T-suppressor (CD8) lymphocytes.

RESULT(S)

The total number of T lymphocytes increased significantly during superovulation, resulting in significantly higher levels in subjects achieving embryo implantation than in those showing a failure of implantation. An opposite trend was observed for the activated T cells. The number of T-helper lymphocytes and the T-helper/T-suppressor ratio showed a significant increase from baseline to the time of pick-up only in patients with implantation.

CONCLUSION(S)

A prolonged condition of stress, which causes a decreased ability to adapt and a transitory anxious state, is associated with high amounts of activated T cells in the peripheral blood. Such a condition, in turn, is associated with a reduced implantation rate in women undergoing IVF-ET.

Autonomic and neuroendocrine responses to stress in patients with functional hypothalamic secondary amenorrhea

OBJECTIVE

To evaluate the ability of women affected by functional hypothalamic secondary amenorrhea (FHSA) or polycystic ovary syndrome (PCOS) to adapt to stress.

DESIGN

Controlled clinical study.

SETTING

University hospital.

PATIENT(S)

Thirty-one patients affected by FHSA, 29 patients with PCOS, and 30 eumenorrheic women.

INTERVENTION(S)

The subjects took the Stroop Color Word (Stroop CW) test and underwent blood sampling.

MAIN OUTCOME MEASURE(S)

Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and serum cortisol levels.

RESULT(S)

The healthy controls had better Stroop CW scores than patients with FHSA. Serum cortisol levels significantly increased during Stroop CW with respect to the baseline in patients with FHSA or PCOS but not in the healthy controls. The SBP, DBP, and HR of the controls as well as SBP and DBP of patients with PCOS were significantly higher than those measured in patients with FHSA both at the baseline and during Stroop CW.

CONCLUSION(S)

Patients with FHSA do not cope as well as healthy patients, and their autonomic response to stress is worse than both controls and patients with PCOS.

Color Doppler and hormone replacement therapy: the role of thromboxane and plasma viscosity

The aim of the study was to evaluate the plasma thromboxane and plasma viscosity in relation with Doppler flow parameters in postmenopausal patients treated with hormone replacement therapy. Thirty-two postmenopausal (follicle-stimulating hormone > 40 IU/l and estradiol < 100 pmol/l) women (mean age +/- SD, 54.7 +/- 2.9 years) participated in the study and were submitted to continuous estradiol transdermal supplementation and 12-day courses of medroxyprogesterone acetate every second month. Doppler resistances at the level of the uterine and internal carotid arteries, thromboxane plasma levels and plasma viscosity were analyzed in basal condition and after 1, 3 and 6 months. During hormone supplementation, the pulsatility index significantly decreased at the level of the analyzed arteries. Similarly, plasma thromboxane levels and plasma viscosity were significantly reduced. Significant correlations were found between thromboxane plasma concentrations, plasma viscosity and uterine artery resistances. Thus hormone replacement therapy seems to be responsible for both direct and indirect modifications at the level of the vessel wall physiology.

Hormonal replacement therapy and urinary problems as evaluated by ultrasound and color Doppler

OBJECTIVE

To determine how hormone replacement therapy modifies bladder vascularization and urinary symptoms.

STUDY DESIGN

Twenty-eight postmenopausal women with urinary symptoms (day-time frequency > 8; nocturia > 1; urgency and/or dysuria) were analyzed before and after 1, 3 and 6 months of hormone replacement therapy. The patients underwent transvaginal ultrasound evaluation of the pelvic organs and endometrial and bladder wall thickness. Transvaginal color Doppler analysis of blood flow impedance of the uterine and intramural bladder wall arteries was performed in all cases.

RESULTS

Hormone replacement therapy significantly increased bladder wall and endometrial thickness. This result was associated with significant improvements in uterine and bladder wall vascularization. Urinary symptoms also improved during therapy.

CONCLUSION

The study of bladder wall thickness and vascularization provides additional information regarding the beneficial effect of hormone replacement therapy on lower urinary tract symptoms in postmenopausal women.

Variations of cardiac performance and inotropism in healthy postmenopausal women treated with estroprogestin replacement therapy

OBJECTIVE

The aim of the present study was to evaluate possible variations in cardiac hemodynamic parameters related to the natural changes of ovarian estrogen production.

METHODS

Forty postmenopausal women aged 52.7 +/- 4.6 years, randomized into two groups (20 patients in each group) according to the administration (group A) or not (group B) of estroprogestin replacement therapy (ERT), were examined using thoracic electrical bioimpedence.

RESULTS

After 6 months of therapy, we observed the following: (1) the mean end-diastolic index was significantly higher in group A than in group B (70.27 and 57.13 mL/m2, respectively) (p < 0.05); (2) the mean acceleration index, indicator of heart contractility, and the mean cardiac index rate, indicators of cardiac performance, were significantly higher in group A than in group B (mean, 1.35 vs. 0.76 s [p < 0.01] and mean, 3.22 vs. 2.34 L/min/m2 [p < 0.05], respectively); and (3) the patients treated with ERT showed systemic vascular resistance index values significantly lower than the controls (mean, 2280 vs. 3150 fOhm/m2 [p < 0.01]), achieving standard levels after 6 months of therapy. Furthermore, the acceleration index showed a significant increase, within group A, between the third and sixth month of ERT (0.91 vs. 1.35 s [p < 0.05]).

CONCLUSIONS

Our findings suggest that postmenopausal women treated with a 6-month course of ERT have significantly improved end-diastolic index, heart contractility index, cardiac index, and systemic vascular resistance, whereas 3 months of ERT does not seem to induce the same effects. In our study, thoracic electrical bioimpedence was shown to be a sensitive and specific method of analysis with a very low cost of administration.

Proopiomelanocortin (POMC) mRNA and POMC-derived peptides immunolocalization in the skin of Protopterus annectens, an African lungfish

Antisera against adrenocorticotropic hormone (ACTH), alpha-melanocyte stimulating hormone (alpha-MSH) and beta-endorphin were used to localize, by immunohistochemistry, proopiomelanocortin (POMC)-derived peptides in the skin excised from different regions of the African lungfish Protopterus annectens. Immunoreactivity was observed in the epidermis mainly in the germinal layer. Using human POMC cDNA as hybridization probe, POMC-like mRNA was identified in situ in epidermal cells. The demonstration in the same cells of POMC mRNA and POMC-related peptides immunoreactivity indicates a local production of opiate hormones.

Increased anticardiolipin antibodies are positively related to the uterine artery pulsatility index in unexplained infertility

The objective of the study was to evaluate, in patients with unexplained infertilty, the possible relationship between anticardiolipin antibodies and indices of uterine artery Doppler measurements. A total of 46 infertile women participated in the study and underwent ovarian stimulation. Transvaginal ultrasonography and colour Doppler were performed on the day of embryo transfer and patients were divided on the basis of pulsatility index (PI): group I, PI <2.5; group II, PI 2.5-3.0; and group III, PI >3.0. On the same day that Doppler analysis took place, peripheral blood was obtained and circulating anticardiolipin antibodies were assayed. The response to ovarian stimulation was similar in the three studied groups. No significant differences in oestradiol and ultrasonographic parameters were observed between the groups. A significant increase in anticardiolipin antibodies was observed in those patients with higher resistance to flow at the level of the uterine artery. A significant relationship was found between the uterine artery PI and anticardiolipin immunoglobulin G class (F = 14.35; P = 0.001), and immunoglobulin M class (F = 5.88; P = 0.020). It is concluded that, in unexplained infertility, anticardiolipin antibodies may be involved in uterine vascular modifications and that Doppler flow analysis of uterine arteries may be an important tool in the assessment and management of ovarian stimulation.

Acetyl salmon endorphin-like and interrenal stress response in male gilthead sea bream, Sparus aurata

The present study investigates the role of melanotrope proopiomelanocortin-derived peptide in the interrenal stress response to different stressors in male gilthead sea bream, Sparus aurata. Plasma cortisol and acetyl salmon endorphin (acetyl s-EP), as well as pituitary acetyl s-EP contents, were measured during two stress paradigms: (a) long-term (1-month) confinement and crowding, and (b) short-term (60-min) confinement, crowding, and manipulation. In addition, naltrexone, a highly specific opioid receptor antagonist, was employed in some experimental groups to evaluate the adaptability of the opioid response to interrenal stress. In the long-term (1-month) confinement and crowding, higher plasma cortisol levels and acetyl s-EP concentrations than in the control group were found. However, although plasma cortisol levels significantly increased in both types of stress paradigm, a significant rise in plasma acetyl s-EP was observed only in the case of confinement plus crowding. These data seem to suggest a direct correlation of acetyl s-EP plasma levels exclusively in cases of specific stress, and support previous observations about the different nature of the pituitary-interrenal stress response in salmonids and in mammals. The results obtained in the short-term (60-min) experiments demonstrate the double activation of both the opioid and corticotrope systems when manipulation plus crowding was applied.

Expression of pro-opiomelanocortin (POMC) in the cerebral ganglion and ovary of a protochordate

The distribution of neurones expressing POMC mRNA in the cerebral ganglion of the protochordate ascidian, Styela plicata, was investigated using a non-radioactive in situ hybridization technique. Nerve cell bodies of mono and bipolar types expressing POMC mRNA, were observed mainly in the outer layer of the ganglion. Discrete groups of neurones containing POMC mRNA were also localized in the inner portion of the ganglion, and few small monopolar perykaria expressing POMC mRNA were visible at the emergence of the main nerve trunks. POMC mRNA labeling was also found at level of the cytoplasm of previtellogenic and vitellogenic oocytes, and of follicular cells. Our results demonstrate the expression of one or more genes in the cerebral ganglion and ovary, that may be similar to one or more regions of the mammalian POMC gene. Therefore POMC-related molecules seem to be involved in neuromodulatory pathways and regulatory mechanisms of the oogenesis of ascidians.

Pro-opiomelanocortin (POMC) expression and immunolocalization of POMC-related peptides in the ovary of Protopterus annectens, an African lungfish

Antisera against adrenocorticotropic hormone (ACTH), alpha-melanocyte-stimulating hormone (alpha MSH) and beta-endorphin were used to localize pro-opiomelanocortin (POMC)-derived peptides in the ovary of the African lungfish Protopterus annectens by immunohistochemistry. Immunoreactivity was observed in the granulosa and the internal theca of the vitellogenic follicles. No immunoreactivity was observed in immature follicles. Using human POMC cDNA as the hybridization probe POMC-like mRNA was identified in situ in cells of the granulosa and internal theca of the vitellogenic follicles. No labeling was observed in primordial follicles. The demonstration in the same cells of POMC mRNA and POMC-related peptides immunoreactivity indicates a local production of the opiate hormones.

Episodic secretion of activin A in pregnant women

The aim of the present study was to determine the characteristics of activin A secretion in women with normal and abnormal pregnancy. With this purpose, a prospective study was done to evaluate the putative pulsatile pattern of serum activin A in serial specimens of blood collected during a certain amount of time (every 15 min for 3 h). A group of pregnant women (N = 24) participated in a cross-sectional study. They were subdivided into three groups: healthy pregnant women (N = 8), patients with preterm labor (N = 8) and patients with gestational diabetes (N = 8) before and after insulin therapy. Secretory pulses of serum activin A were determined in all patients with a specific frequency and amplitude by using two different computerized analyses, i.e. DETECT and CLUSTER. Mean +/- SEM values of serum activin A were significantly higher in patients with preterm labor and gestational diabetes than in controls (p < 0.01), showing a significant decrease following insulin therapy in diabetic patients (p < 0.01). Specific pulses of serum activin A levels were observed in all women. The mean pulse frequency did not change significantly between healthy controls and the different pathological groups. Patients with gestational diabetes after insulin therapy showed a pulse frequency that was significantly higher than in controls (p < 0.05). When the mean peak amplitude of activin A pulses was evaluated, patients with preterm labor or gestational diabetes showed values that were significantly higher than in healthy pregnant women (p < 0.01) A significant, inverse correlation between pulse frequency and amplitude was found both in healthy pregnant women (p < 0.05) and in patients with gestational diabetes (p < 0.001). The present study showed that circulating activin A levels in pregnant women change in a pulsatile pattern whose pulse amplitude is modified in the presence of gestational diseases, such as preterm labor or gestational diabetes.

Impact of the L-arginine/nitric oxide system in pregnancy

Nitric Oxide (NO) recently becomes of clinical interest because of its relaxant effects on smooth muscle. In addition to endothelial cells, also myometrial cells contain the enzyme implicated in the NO production. This review is aimed toward those studies concerned with the production, metabolism, and effects of NO that could be relevant for the obstetricians. The potential clinical interest of such information covers the main areas of pregnancy complications, namely preterm delivery, preeclampsia, and intrauterine growth retardation. Moreover, original data are included in order to support the therapeutical implications of the manipulation of L-arginine-NO system in case of pregnancy disorders.

Hypertension in pregnancy: changes in activin A maternal serum concentration

Human placenta is the major source of activin A in maternal circulation. The aim of the present study was to evaluate maternal activin A serum concentration in pregnant women with chronic hypertension (n = 14), pregnancy-induced hypertension (n = 10) or pre-eclampsia (n = 16). In the group of pregnant women with chronic hypertension and of healthy pregnant women (n = 10) activin A was measured in samples collected longitudinally throughout gestation. Using a specific two-site enzyme-linked immunosorbent assay, it has been possible to measure maternal serum activin A concentration. In addition, the effect of recombinant human activin A administration on mean arterial pressure and heart rate in female rats have been also investigated. Mean +/- SEM of maternal serum activin A concentration in pre-eclamptic women (57.4 +/- 28.3 ng/ml), was significantly higher than in women with pregnancy-induced hypertension (14.8 +/- 10.5 ng/ml), chronic hypertension (10.3 +/- 5.4 ng/ml) or healthy control women (9.2 +/- 9.4 ng/ml) (P < 0.01). Serum activin A levels evaluated 2 weeks after anti-hypertensive treatment were not significantly different in pre-eclamptic women. Moreover, when exogenous recombinant human activin A was administered in female rats arterial pressure or frequency of heart rate did not change. The present study showed that maternal serum activin A concentration is abnormally high in patients with pre-eclampsia. Thus, since the patients with chronic hypertension or pregnancy-induced hypertension have activin A concentration in the normal range of values, activin A may be a prognostic marker of hypertension in pregnancy.

Steroid-protein interaction in human placenta

Human placenta produces a large variety of bioactive substances with endocrine and neural competence: pituitary and gonadal hormones, hypothalamic-like releasing or inhibiting hormones, growth factors, cytokines and neuropeptides. The most recent findings indicate that locally produced hormones regulate the secretion of other placental hormones supporting a paracrine/autocrine regulation. In placental endocrinology, a particular relevance is played by steroid hormones. In fact, a specific gonadotropin-releasing hormone (GnRH)-human chorionic gonadotropin (hCG) regulation of placental steroidogenesis has been proposed as a placental internal regulatory system acting on steroids production from human placenta. In addition, activin and inhibin have been proposed as further regulatory substances of the synthesis and secretion of steroids; the addition of activin A to placental culture augments GnRH, hCG and progesterone, and this effect can be significantly reduced by the addition of inhibins. Finally, a steroid-steroid interaction is suggested by the evidence that placental estrogen has a positive role in the regulation of progesterone biosynthesis. Other steroid-protein interactions have been observed in human placenta. In fact, recent data indicate that progesterone inhibits placental corticotropin-releasing factor (CRF) and estrogens act on placental conversion of cortisol to cortisone, activating cortisol secretion by the fetal adrenal and enhancing fetal adrenal function with advancing gestation.

Expression of pro-opiomelanocortin gene in human ovarian tissue

The high concentration of pro-opiomelanocortin (POMC)-derived peptides in human follicular fluid, which is several times higher than in plasma, suggested a local expression of the POMC gene. This has previously been observed in the animal ovaries. Peripheral POMC-like mRNAs are not translated in POMC-derived peptides but recent evidence supports the presence of a small amount of full-length transcript in human testes and lymphocytes. The purpose of this study was to test two hypotheses: firstly, that there is a different pattern of POMC mRNA expression in the human ovary of fertile and post-menopausal women, and secondly that there is a tissue-specific localization of POMC transcript. Northern blot analysis showed that a potential relationship exists between POMC gene expression and the reproductive age of a woman, and that POMC mRNA has a tissue-specific localization. The expression of POMC messenger in the ovarian parenchyma collected from women of fertile age and in the germinative follicles appeared higher than that observed in samples from post-menopausal women. No signals were detected in corpora lutea. In conclusion, we believe that the physiological role of the POMC gene in the human ovary remains an unsolved problem, necessitating more sensitive methods of mRNA detection as well as further studies in vitro.

[Beta-cell secretion in patients with thalassemia major]

Diabetes mellitus is one of the main endocrinological disease complicating the course of thalassemia major. This study aimed evaluate beta-cell secretion in 24 patients with thalassemia major attending the hematological Day Hospital at the Pediatric Clinic in Modena where transfusion therapy is performed in all thalassemic patients so as to maintain minimum hemoglobin levels above 10.5 g/dl, together with intensive ferrochelating therapy (desferrioxamine 50-60 mg/kg/die s.c. 6 days a week). A C peptide challenge with glucagon was performed in three patients already receiving insulin therapy for diabetes mellitus; this unexpectedly revealed a slight residual beta-cell secretion. An intravenous glucose tolerance test (IVGTT) was performed in the remaining 21 non-diabetic patients, with widely varying findings regarding insulin secretion: from below 50 microUl/ml in 5 patients to above 200 microUl/ml in 5 patients, and between 50 and 150 microUl/ml in the remaining 11 patients. This study therefore confirmed that insulin secretion frequently alters in thalassemic patients. Moreover, insulin secretion is not correlated to ferritinemia or influenced by familiar diabetes or patient age.

Abnormal concentration of maternal serum activin-A in gestational diseases

Serum plasma activin-A is measurable in the maternal circulation of healthy pregnant women, increases in specimens collected during the third trimester of gestation, and is highest at parturition. Hormone abnormalities are known to be associated with preterm labor or diabetes in pregnancy. Therefore, in the present study serum activin-A levels in normal controls were compared to those in pregnant women with preterm labor or gestational diabetes. In some cases, values were obtained before and after insulin therapy. In other controls and patients with preterm labor, the activin-A concentration in cord serum was also studied. A newly developed two-site immunotest was used to determine activin-A levels. Subjects included normal controls (n = 7), who were sampled throughout gestation every 5 weeks; pregnant women at term (38-40 weeks) not in labor (n = 22); pregnant women at term in spontaneous labor (< 3.0 cm dilated; n = 42); women in preterm labor (25-35 weeks; n = 38); and women with gestational diabetes (20-39 weeks; n = 9). In control women, serum activin-A levels increased from 4.8 +/- 5.5 micrograms/L (mean +/- SD) at 20 weeks to 25.4 +/- 27.8 micrograms/L at 40 weeks (P < 0.01), and values correlated with gestational age. Pregnant women in preterm labor had serum activin-A concentrations (89.04 +/- 173.31 micrograms/L) higher than those in normal controls (P < 0.01), and no significant correlation to gestational age was found in this group of pregnant women. Healthy women in labor showed serum activin-A concentrations higher than those in women at term but not in labor (P < 0.01). Diabetic patients had serum activin-A concentrations (52.39 +/- 23.32 micrograms/L) significantly higher than those in normal controls. In these patients, maternal serum activin-A concentrations significantly decreased to the range in healthy controls at the same gestational age after insulin therapy (9.48 +/- 3.82 micrograms/L). The present study shows that preterm labor is associated with increased concentrations of activin-A in the maternal circulation and cord serum. Hypersecretion of activin-A is also shown in same patients with gestation diabetes; this reverts to normal after insulin treatment.

Activin at parturition: changes of maternal serum levels and evidence for binding sites in placenta and fetal membranes

OBJECTIVE

To evaluate maternal serum activin A levels in pregnant women at parturition, correlated to the mode of delivery, and to localize activin receptor messenger RNA in human placenta and fetal membranes.

METHODS

A specific two-site enzyme-linked immunosorbent assay (ELISA) was used to measure maternal activin A levels. Activin receptor mRNA was localized in placenta and fetal membranes by in situ hybridization, using ActRII or ActRIIB antisense riboprobes.

RESULTS

Serum activin A levels increased significantly in pregnant women during vaginal or cesarean delivery after spontaneous labor. No significant changes of serum activin A were found in patients undergoing elective cesarean delivery. Syncytiotrophoblast and amnion cells hybridized to radiolabeled ActRIIB probe, whereas few cells within the structure of the villi and decidual cells hybridized to radiolabeled ActRII probe.

CONCLUSION

The present studies indicate that vaginal or cesarean delivery following spontaneous labor is characterized by increased activin A levels and that activin receptors are present on trophoblast and fetal membranes.

Pulsatile fluctuations of plasma-gonadotropin-releasing hormone and corticotropin-releasing factor levels in healthy pregnant women

Several data emphasize the neuroendocrine aspects of human placenta. Classical hypophyseotropic neurohormones are produced and secreted by the human placenta. Indeed, in contrast with non pregnant subjects, gonadotropin-releasing hormone (GnRH) and corticotropin-releasing factor (CRF) are measurable in maternal plasma during pregnancy. The aim of the present study was to investigate the characteristics of the secretory pattern of maternal plasma GnRH and CRF levels. A total of 25 healthy pregnant women participated in the present cross-sectional study. Plasma levels of the two neurohormones were measured according to three different time-intervals: 1) every five minutes for eight hours (n = 4), 2) every ten minutes for four hours (n = 15), 3) every four hours for 24 hours (n = 7). Following an acidic extraction plasma GnRH and CRF levels were measured by specific radioimmunoassay. Using two different algorithms (Detect and Cluster) a pulsatile pattern for both plasma GnRH and CRF levels was observed. Specific pulse frequency, amplitude, and duration were found. In the groups of women studied with a longer sampling interval, pulse frequency of GnRH or CRF levels did not differ between first and third trimester of gestation. However, amplitude of CRF pulses were significantly higher at term than at early stages of pregnancy (p < 0.01), while GnRH pulse amplitude was highest in women at first trimester of gestation. Evaluating the degree of concordance in all subjects, GnRH pulses significantly correlated with CRF pulses at 30 min. lag (p < 0.01). No significant circadian changes were found for any circulating neurohormone measured.(ABSTRACT TRUNCATED AT 250 WORDS)

Local production and action of follistatin in human placenta

The aim of the present study was to investigate the possible production, localization, and action of follistatin in human placenta, fetal membranes (amnion, chorion), and maternal decidua. Four different experimental approaches were used: 1) Southern blot analysis following reverse polymerase chain reaction to identify follistatin messenger RNA (mRNA) in tissue homogenates; 2) immunohistochemistry to localize immunoreactive (ir-) follistatin in the various intrauterine tissues; 3) measurement by RIA of ir-follistatin levels in culture medium of placental cells; and 4) possible action of follistatin on human CG (hCG) and progesterone release from cultured placental cells. Placental and decidual cells collected during first trimester or at term gestation express follistatin mRNA; fetal membranes (amnion, chorion) at term also express follistatin mRNA. Immunoreactive follistatin is localized in syncytial cells of placental villi at term as well as in large decidual cells, in amnion epithelium, and in chorionic cells. The placental secretion of follistatin has been confirmed by the evidence of measurable levels of ir-follistatin in the medium of cultured placental cells at term; the release is time dependent and is not modified by the addition of forskolin or progesterone. The addition of increasing doses of recombinant human follistatin does not significantly influence the release of hCG or progesterone from cultured placental cells, whereas the activin A-induced hCG and progesterone release are completely reversed. The present data showed that 1) human placenta, fetal membranes, and decidua express follistatin mRNA; 2) ir-follistatin is localized and released from placental cells at term; and 3) follistatin has a functional role in the local control system regulating placental hormone production.

Effect of different chronic intermittent stressors and acetyl-l-carnitine on hypothalamic beta-endorphin and GnRH and on plasma testosterone levels in male rats

Chronic stress affects the reproductive function by modifying the neuroendocrine homeostasis. The aim of the present study was to clarify the neuroendocrine and the gonadal changes following chronic intermittent stress in male rats and the action of a neuroactive drug, acetyl-l-carnitine (ALC). The effect of two different stressors, cold water swimming or ether, on central beta-endorphin (beta-EP) and GnRH contents, and on plasma testosterone levels was investigated. In addition, the response to an acute stress in chronically stressed rats, treated or untreated with ALC (10 mg/day/rat p.o.), was evaluated. The stressors were applied twice a day for 10 days, and rats were killed before, during and after the last stress session. Mediobasal hypothalamus (MBH) beta-EP and GnRH contents, and plasma testosterone levels were evaluated by radioimmunoassay. The following results were obtained: (1) both chronic swimming and ether stress caused a decrease in hypothalamic beta-EP contents; (2) MBH GnRH contents increased after chronic swimming stress but not after ether stress; (3) chronic swimming stress induced a twofold decrease in plasma testosterone levels, while no changes were observed after ether stress; (4) the treatment with ALC prevented the decrease in plasma testosterone levels after chronic swimming stress, and (5) acute stress in chronically stressed animals caused an increase in MBH-beta-EP. The present data showed that chronic swimming stress reduces the reproductive capacity and impairs the capacity to respond to the acute stress and that ALC modulates the hormonal changes to physical stress and prevents the antireproductive effect of chronic cold swimming.

Acetyl-L-carnitine effect on pituitary and plasma beta-endorphin responsiveness to different chronic intermittent stressors

The aims of the present study were: 1) to compare the effect of two different chronic intermittent stressors i.e. cold-swimming versus ether, on the pituitary opioidergic system; 2) to evaluate the response of pituitary and plasma beta-endorphin (beta-EP) to an acute stress in chronically stressed rats; and 3) to evaluate the effect of acetyl-l-carnitine treatment (10 mg/day/rat per os at night) on pituitary and plasma beta-EP changes induced by two different types of chronic stress. The stressors were applied twice a day for 10 days. Rats were killed either before, during or after the last swimming or ether stress session. beta-EP was measured by radioimmunoassay in anterior pituitary and in neurointermediate lobe extracts and in plasma. The following observations were made: 1) Chronic intermittent cold-swimming stress increased anterior pituitary contents and plasma beta-EP levels; 2) both chronic intermittent cold-swimming stress and ether stress caused an increase of neurointermediate lobe beta-EP contents; 3) as in control animals, rats exposed to chronic intermittent swimming stress reduced pituitary beta-EP contents and raised plasma beta-EP levels in response to the last acute swimming stress; 4) in contrast to control animals, rats exposed to chronic intermittent ether stress did not show any significant response of the pituitary-plasma opioidergic system to the last acute ether session; 5) the acetyl-l-carnitine treatment counteracted the changes evoked by chronic intermittent cold-swimming stress on the pituitary and plasma beta-EP levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Corticotropin-releasing hormone modulates cytokines release in cultured human peripheral blood mononuclear cells

Immune and neuroendocrine systems interact at various levels. In particular, either cytokines activate the hypothalamus-pituitary-adrenal axis (HPA) or corticotropin-releasing hormone (CRH) induces the release of beta-endorphin from peripheral human mononuclear cells. The aim of the present study was to investigate whether CRH may affect cytokine production and activity in human peripheral blood mononuclear cells (PBMC). Primary cultures of human PBMC and monocytes were used. They were incubated in presence of different doses of synthetic human CRH. Media were collected and interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) levels were measured by ELISA, while interferon-gamma (IFN-gamma) levels were measured by bioassay. In addition, phytohemoagglutinin-induced lymphocyte proliferation was evaluated by testing [3H]thymidine incorporation in the presence of various doses of CRH. CRH significantly increased IL-6 release from PBMC (p < 0.01). The addition of CRH to PBMC significantly decreased IFN-gamma levels, in a dose dependent manner (p < 0.01). No significant effect of CRH was observed on lymphocyte proliferation or IL-1 beta production. The present results suggest a role for CRH as a paracrine mediator for human immune cells, increasing the evidence of a clear correlation between immune and neuroendocrine system.

Deficit of galanin-like immunostaining in the median eminence of adult hypothyroid rats

In this paper we describe the modification of the galanin (GAL)-like immunostaining in the hypothalamus of rats, which were made hypothyroid at 52 days after birth. On 21st day after the surgical ablation of the thyroid gland, the staining of the GAL-immunoreactive fibers in the median eminence decreased and on the 84th day disappeared almost totally. The GAL-immunoreactive distribution in other areas of the hypothalamus, e.g. the anterior hypothalamus and the dorsomedial nucleus, is only slightly affected by the absence of thyroid hormones, whereas the GAL-staining of medulla oblongata (vagal complex) is equal in both control and hypothyroid rats. In hypothyroid colchicine-treated rats, we were unable to stain GAL-immunoreactive neurons in the paraventricular nucleus (PVN). Oxytocin- and vasopressin-like material was present in the magnocellular neurons and the staining pattern in hypothyroid rats was the same as that of control animals. Our data show a marked reduction in the expression of the GAL-like immunoreactivity of the PVN and median eminence of adult hypothyroid rats. The possible role of this deficit in the pathogenesis of the GH secretion impairment that is observed in hypothyroid rats is discussed.