Influence of Bariatric Surgery on Gut Microbiota Composition and Its Implication on Brain and Peripheral Targets

Obesity remains a significant global health challenge, with bariatric surgery remaining as one of the most effective treatments for severe obesity and its related comorbidities. This review highlights the multifaceted impact of bariatric surgery beyond mere physical restriction or nutrient malabsorption, underscoring the importance of the gut microbiome and neurohormonal signals in mediating the profound effects on weight loss and behavior modification. The various bariatric surgery procedures, such as Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG), act through distinct mechanisms to alter the gut microbiome, subsequently impacting metabolic health, energy balance, and food reward behaviors. Emerging evidence has shown that bariatric surgery induces profound changes in the composition of the gut microbiome, notably altering the Firmicutes/Bacteroidetes ratio and enhancing populations of beneficial bacteria such as Akkermansia. These microbiota shifts have far-reaching effects beyond gut health, influencing dopamine-mediated reward pathways in the brain and modulating the secretion and action of key gut hormones including ghrelin, leptin, GLP-1, PYY, and CCK. The resultant changes in dopamine signaling and hormone levels contribute to reduced hedonic eating, enhanced satiety, and improved metabolic outcomes. Further, post-bariatric surgical effects on satiation targets are in part mediated by metabolic byproducts of gut microbiota like short-chain fatty acids (SCFAs) and bile acids, which play a pivotal role in modulating metabolism and energy expenditure and reducing obesity-associated inflammation, as well as influencing food reward pathways, potentially contributing to the regulation of body weight and reduction in hedonic eating behaviors. Overall, a better understanding of these mechanisms opens the door to developing non-surgical interventions that replicate the beneficial effects of bariatric surgery on the gut microbiome, dopamine signaling, and gut hormone regulation, offering new avenues for obesity treatment.

Nutrition at the Intersection between Gut Microbiota Eubiosis and Effective Management of Type 2 Diabetes

Nutrition is one of the most influential environmental factors in both taxonomical shifts in gut microbiota as well as in the development of type 2 diabetes mellitus (T2DM). Emerging evidence has shown that the effects of nutrition on both these parameters is not mutually exclusive and that changes in gut microbiota and related metabolites such as short-chain fatty acids (SCFAs) and branched-chain amino acids (BCAAs) may influence systemic inflammation and signaling pathways that contribute to pathophysiological processes associated with T2DM. With this background, our review highlights the effects of macronutrients, carbohydrates, proteins, and lipids, as well as micronutrients, vitamins, and minerals, on T2DM, specifically through their alterations in gut microbiota and the metabolites they produce. Additionally, we describe the influences of common food groups, which incorporate varying combinations of these macronutrients and micronutrients, on both microbiota and metabolic parameters in the context of diabetes mellitus. Overall, nutrition is one of the first line modifiable therapies in the management of T2DM and a better understanding of the mechanisms by which gut microbiota influence its pathophysiology provides opportunities for optimizing dietary interventions.

"Knee-Ding" a Diagnosis: A Case of Nail Patella Syndrome

Nail Patella Syndrome (NPS) is a rare genetic disorder with pathognomonic signs including dystrophic fingernails, iliac horns, and limb abnormalities, which commonly include hypoplastic development of the patellae, causing patients to experience patellar instability. This resulting patellar instability increases susceptibility to recurrent subluxations or dislocations in NPS patients. Since these anatomical abnormalities are present at birth or in childhood, early recognition may prevent the need for surgical intervention if appropriate preventive measures are taken. This case report describes a 54-year-old woman with a history of NPS, diagnosed later in adulthood, with a prior patellectomy at age 18 secondary to an unspecified left knee injury that occurred at age 4. A combination of radiographic and clinical findings are presented, which support the diagnosis of NPS, including dystrophic nails, left knee x-ray consistent with prior patellectomy, and right knee x-ray showing inferolateral subluxation of a hypoplastic patella. Additional signs associated with NPS are also discussed, including mood disorders, Raynaud's, and a high hairline which may assist in early diagnosis. This case report emphasizes earlier identification of NPS by clinicians through recognition of signs and symptoms while also considering proactive measures to lessen recurrent subluxations or dislocations to preserve patellar integrity and reduce the need for surgical intervention.

Should we perform oocyte accumulation to preserve fertility in women with Turner syndrome? A multicenter study and systematic review of the literature

STUDY QUESTION

Should we perform oocyte accumulation to preserve fertility in women with Turner syndrome (TS)?

SUMMARY ANSWER

The oocyte cryopreservation strategy is not well adapted for all TS women as their combination of high basal FSH with low basal AMH and low percentage of 46,XX cells in the karyotype significantly reduces the chances of freezing sufficient mature oocytes for fertility preservation.

WHAT IS KNOWN ALREADY

An oocyte cryopreservation strategy requiring numerous stimulation cycles is needed to preserve fertility in TS women, to compensate for the low ovarian response, the possible oocyte genetic alterations, the reduced endometrial receptivity, and the increased rate of miscarriage, observed in this specific population. The validation of reliable predictive biomarkers of ovarian response to hormonal stimulation in TS patients is necessary to help practitioners and patients choose the best-personalized fertility preservation strategy.

STUDY DESIGN, SIZE, DURATION

A retrospective bicentric study was performed from 1 January 2011 to 1 January 2023. Clinical and biological data from all TS women who have received from ovarian stimulation for fertility preservation were collected. A systematic review of the current literature on oocyte retrieval outcomes after ovarian stimulation in TS women was also performed (PROSPERO registration number: CRD42022362352).

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 14 TS women who had undergone ovarian stimulation for fertility preservation were included, representing the largest cohort of TS patients published to date (n = 14 patients, 24 cycles). The systematic review of the literature identified 34 additional TS patients with 47 oocyte retrieval outcomes after ovarian stimulation in 14 publications (n = 48 patients, n = 71 cycles in total).

MAIN RESULTS AND THE ROLE OF CHANCE

The number of cryopreserved mature oocytes on the first cycle for TS patients was low (4.0 ± 3.7). Oocyte accumulation was systematically proposed to increase fertility potential and was accepted by 50% (7/14) of patients (2.4 ± 0.5 cycles), leading to an improved total number of 10.9 ± 7.2 cryopreserved mature oocytes per patient. In the group who refused the oocyte accumulation strategy, only one patient exceeded the threshold of 10 mature cryopreserved oocytes. In contrast, 57.1% (4/7) and 42.9% (3/7) of patients who have underwent the oocyte accumulation strategy reached the threshold of 10 and 15 mature cryopreserved oocytes, respectively (OR = 8 (0.6; 107.0), P = 0.12; OR= 11 (0.5; 282.1), P = 0.13). By analyzing all the data published to date and combining it with our data (n = 48 patients, n = 71 cycles), low basal FSH and high AMH concentrations as well as a higher percentage of 46,XX cells in the karyotype were significantly associated with a higher number of cryopreserved oocytes after the first cycle. Moreover, the combination of low basal FSH concentration (<5.9 IU/l), high AMH concentration (>1.13 ng/ml), and the presence of 46,XX cells (>1%) was significantly predictive of obtaining at least six cryopreserved oocytes in the first cycle, representing objective criteria for identifying patients with real chances of preserving an adequate fertility potential by oocyte cryopreservation.

LIMITATIONS, REASONS FOR CAUTION

Our results should be analyzed with caution, as the optimal oocyte number needed for successful live birth in TS patients is still unknown due to the low number of reports their oocyte use in the literature to date.

WIDER IMPLICATIONS OF THE FINDINGS

TS patients should benefit from relevant clinical evaluation, genetic counseling and psychological support to make an informed choice regarding their fertility preservation technique, as numerous stimulation cycles would be necessary to preserve a high number of oocytes.

STUDY FUNDING/COMPETING INTEREST(S)

This research received no external funding. The authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Dietary Fat Modulation of Gut Microbiota and Impact on Regulatory Pathways Controlling Food Intake

Obesity is a multifactorial disease that continues to increase in prevalence worldwide. Emerging evidence has shown that the development of obesity may be influenced by taxonomic shifts in gut microbiota in response to the consumption of dietary fats. Further, these alterations in gut microbiota have been shown to promote important changes in satiation signals including gut hormones (leptin, ghrelin, GLP-1, peptide YY and CCK) and orexigenic and anorexigenic neuropeptides (AgRP, NPY, POMC, CART) that influence hyperphagia and therefore obesity. In this review, we highlight mechanisms by which gut microbiota can influence these satiation signals both locally in the gastrointestinal tract and via microbiota-gut-brain communication. Then, we describe the effects of dietary interventions and associated changes in gut microbiota on satiety signals through microbiota-dependent mechanisms. Lastly, we present microbiota optimizing therapies including prebiotics, probiotics, synbiotics and weight loss surgery that can help restore beneficial gut microbiota by enhancing satiety signals to reduce hyperphagia and subsequent obesity. Overall, a better understanding of the mechanisms by which dietary fats induce taxonomical shifts in gut microbiota and their impact on satiation signaling pathways will help develop more targeted therapeutic interventions in delaying the onset of obesity and in furthering its treatment.

Reduced Striatal Dopamine Transporter Availability and Heightened Response to Natural and Pharmacological Stimulation in CCK-1R-Deficient Obese Rats

Alterations in dopamine neurotransmission are associated with obesity and food preferences. Otsuka Long-Evans Tokushima Fatty (OLETF) rats that lack functional cholecystokinin receptor type-1 (CCK-1R), due to a natural mutation, exhibit impaired satiation, are hyperphagic, and become obese. In addition, compared to lean control Long-Evans Tokushima (LETO) rats, OLETF rats have pronounced avidity for over-consuming palatable sweet solutions, have greater dopamine release to psychostimulants, reduced dopamine 2 receptor (D2R) binding, and exhibit increased sensitivity to sucrose reward. This supports altered dopamine function in this strain and its general preference for palatable solutions such as sucrose. In this study, we examined the relationship between OLETF's hyperphagic behavior and striatal dopamine signaling by investigating basal and amphetamine stimulated motor activity in prediabetic OLETF rats before and after access to sucrose solution (0.3 M) compared to non-mutant control LETO rats, as well as availability of dopamine transporter (DAT) using autoradiography. In the sucrose tests, one group of OLETF rats received ad libitum access to sucrose while the other group received an amount of sucrose equal to that consumed by the LETO. OLETFs with ad libitum access consumed significantly more sucrose than LETOs. Sucrose exerted a biphasic effect on basal activity in both strains, i.e., reduced activity for 1 week followed by increased activity in weeks 2 and 3. Basal locomotor activity was reduced (-17%) in OLETFs prior to sucrose, compared to LETOs. Withdrawal of sucrose resulted in increased locomotor activity in both strains. The magnitude of this effect was greater in OLETFs and the activity was increased in restricted compared to ad-libitum-access OLETFs. Sucrose access augmented AMPH-responses in both strains with a greater sensitization to AMPH during week 1, an effect that was a function of the amount of sucrose consumed. One week of sucrose withdrawal sensitized AMPH-induced ambulatory activity in both strains. In OLETF with restricted access to sucrose, withdrawal resulted in no further sensitization to AMPH. DAT availability in the nucleus accumbens shell was significantly reduced in OLETF compared with aged-matched LETO. Together, these findings show that OLETF rats have reduced basal DA transmission and a heightened response to natural and pharmacological stimulation.

Rhinitis associated with asthma is distinct from rhinitis alone: The ARIA-MeDALL hypothesis

Asthma, rhinitis and atopic dermatitis (AD) are interrelated clinical phenotypes that partly overlap in the human interactome. The concept of "one-airway-one-disease", coined over 20 years ago, is a simplistic approach of the links between upper- and lower-airway allergic diseases. With new data, it is time to reassess the concept. This article reviews (i) the clinical observations that led to Allergic Rhinitis and its Impact on Asthma (ARIA), (ii) new insights into polysensitisation and multimorbidity, (iii) advances in mHealth for novel phenotype definition, (iv) confirmation in canonical epidemiologic studies, (v) genomic findings, (vi) treatment approaches and (vii) novel concepts on the onset of rhinitis and multimorbidity. One recent concept, bringing together upper- and lower-airway allergic diseases with skin, gut and neuropsychiatric multimorbidities, is the "Epithelial Barrier Hypothesis". This review determined that the "one-airway-one-disease" concept does not always hold true and that several phenotypes of disease can be defined. These phenotypes include an extreme "allergic" (asthma) phenotype combining asthma, rhinitis and conjunctivitis. Rhinitis alone and rhinitis and asthma multimorbidity represent two distinct diseases with the following differences: (i) genomic and transcriptomic background (Toll-Like Receptors and IL-17 for rhinitis alone as a local disease; IL-33 and IL-5 for allergic and non-allergic multimorbidity as a systemic disease), (ii) allergen sensitisation patterns (mono- or pauci-sensitisation versus polysensitisation), (iii) severity of symptoms and (iv) treatment response. In conclusion, rhinitis alone (local disease) and rhinitis with asthma multimorbidity (systemic disease) should be considered as two distinct diseases, possibly modulated by the microbiome, and may be a model for understanding the epidemics of chronic and auto-immune diseases.

Fecal microbiota transplantation in non-communicable diseases: Recent advances and protocols

Fecal microbiota transplant (FMT) is a therapeutic method that aims to restore normal gut microbial composition in recipients. Currently, FMT is approved in the USA to treat recurrent and refractory Clostridioides difficile infection and has been shown to have great efficacy. As such, significant research has been directed toward understanding the potential role of FMT in other conditions associated with gut microbiota dysbiosis such as obesity, type 2 diabetes mellitus, metabolic syndrome, neuropsychiatric disorders, inflammatory bowel disease, irritable bowel syndrome, decompensated cirrhosis, cancers and graft-versus-host disease. This review examines current updates and efficacy of FMT in treating conditions other than Clostridioides difficile infection. Further, protocols for administration of FMT are also discussed including storage of fecal samples in stool banks, inclusion/exclusion criteria for donors, fecal sample preparation and methods of treatment administration. Overall, understanding the mechanisms by which FMT can manipulate gut microbiota to provide therapeutic benefit as well as identifying potential adverse effects is an important step in clarifying its long-term safety and efficacy in treating multiple conditions in the future.

[What issues, changes and adaptations for French ART centers in the context of the new bioethics law?]

OBJECTIVE

This review intends to introduce the changes of the new Bioethics law in the reproductive field and its application in French ART centers.

MATERIAL AND METHODS

The review details the main provisions of the Bioethics Law of August 2nd 2021 as well as the three decrees published since: the first one on September 29th 2021, which specifies in particular the age conditions to benefit from ART and self-preservation of one's gametes; another decree on December 31st, 2021, to set the terms and conditions for gamete self-preservation activities for non-medical reasons and the last decree on April 14th 2022, relating to the allocation of donated gametes and embryo donation.

RESULTS

Since the law of August 2nd, 2021, access conditions to assisted reproductive technology (ART) have evolved in France. Previously based on pathological infertility or the risk of transmission of a serious disease, ART is now intended to respond to the parental project of a couple formed by a man and a woman, two women or an unmarried woman. With the widening of access conditions, the use of gamete donation will likely increase. The upcoming raise of children born from gamete donation has led the legislator to question their right to access their origin. From September 1st 2022, adults born from gamete donation will be able to request a special administrative authority in order to access the donor's non identifying data (age, physical characteristics, family and professional situation, motivation for the donation…) and/or the donor's identity. Moreover, the new bioethics law opens up the possibility of autologous gamete cryopreservation without medical reasons, under specific age conditions, in order to carry out an assisted reproduction technique later. If gametes are not used, autologous gamete preservation could also allow an increase in gamete donation. However, the modification of gamete donation conditions could suggest a short term decrease in donors' number. Finally, the new bioethics law further opens up research on human embryos and embryonic stem cells.

CONCLUSION

The arrangements introduced by the Bioethics Law promulgated on August 2nd, 2021 represent a major revolution in the field of Reproductive Medicine and are expected to transform the practices of reproductive biology centers and CECOS in France.

[HLA-C KIR interactions and placental defects: Implications in ART pregnancy issues]

OBJECTIVE

The aim of this review is to update data concerning the impact of HLA-C KIR system on placental disorders and assess the involvement on ART clinical outcomes.

METHOD

Ensuring the maintenance of human pregnancy requires the set up of immunological tolerance to prevent foetus rejection. This phenomenon involves different actors of the immune system: among them, uterine NK cells (uNK) hold specific KIR (killer-cell immunoglobulin-like) receptors linking to HLA molecules on the surface of trophoblastic cells at implantation. Many studies provided evidence that the specific interaction between maternal KIR and foetal HLA-C could influence the process of placentation; according to the KIR haplotype and the type of HLA-C, the interaction could be detrimental for placental function. We reviewed the latest data available regarding HLA-C KIR interactions and ART outcomes.

RESULTS

The available results highlight a significant increase of preeclampsia risk and recurrent miscarriages when the maternal inhibitory haplotype KIR AA is present, this risk is all the more enhanced when the interaction occurs with foetal HLA-C2. Recent data suggest the consequences of this detrimental interaction in case of DET (double embryo transfer) or use of donor's oocytes in ART practice. On the other hand, maternal KIR AB or BB haplotypes haven't been related to an additional obstetrical risk, as well as the foetal HLA-C1 homozygous allotype.

CONCLUSION

Despite the existence of many confoundings in current literature on the subject, interaction between maternal KIR and foetal HLA-C represent a promising target lead to broaden the spectrum of placental defects etiologies, especially in the reproductive health area.

P-219 Does artificial shrinkage prior to fresh blastocyst transfer improve ongoing pregnancy rate? A prospective double blind randomized controlled trial

Study question

Does artificial shrinkage (AS) of blastocoelic cavity (BC) prior to fresh elective single blastocyst transfer (SBET) increase ongoing pregnancy rate?

Summary answer

Ongoing pregnancy rates were similar with or without AS of blastocoelic cavity. AS does not seem to provide benefit before fresh blastocyst transfer.

What is known already

AS of the vitrified blastocysts enhances success rate in frozen embryo transfer cycles.

In vitro cultured embryos suffer changes in temperature, pH and osmotic pressure. Moreover, manipulations such as pipetting, fertilization, microscopic observations and changes of dishes can induce oxidative stress and apoptosis. The presence of cell free DNA (cfDNA) in blastocyst fluids could be the consequence of its release from dead cells. The quantity of cfDNA in blastocyst fluids could possibly be related to the rate of cell death. It is thus interesting to estimate whether AS of BC could improve the implantation rate in cycles with fresh blastocyst transfer.

Study design, size, duration

Prospective, randomized, double blind controlled study. From May 20th 2018 to June 30th 2021, 150 couples elected for fresh SBET were included in the study and were randomly selected as “AS +” group (n = 100), where AS of blastocoel was performed by laser pulse before fresh blastocyst transfer, and “AS -” group (n = 50), where fresh blastocysts were transferred without any additional intervention.

Participants/materials, setting, methods

On day 5 after fertilization, one blastocyst with a grade of expansion B3, B4, B5 or B6 and type A or B quality trophectoderm (Gardner and Schoolcraft classification, 1999) was selected for transfer. After replacement, the droplet that contained the embryo from day 3 was collected for cfDNA level quantification.

Ongoing pregnancy rate was determined by the visualization of a gestational sac with a foetal heartbeat 6 weeks later and cfDNA was assessed by ALU-qPCR.

Main results and the role of chance

The two groups were similar for age, BMI, infertility duration and cause, stimulation characteristics and embryological parameters. The global ongoing pregnancy rate per transfer after SBET was 49.7 %. The pregnancy rate in the AS + group was slightly higher than in the control group but not significantly (respectively 50.00 % and 48,9 %, p = 0,91).

cfDNA median value in the AS+ group was comparable to the control group (0.493 (0.219; 0.915) mg/ml and 0.595 (0.271; 1.129) mg/ml respectively (p = 0.45)). No link was found between cfDNA rate and clinical pregnancy rate.

Limitations, reasons for caution

Patients included in the study are still followed to evaluate the impact of AS on live birth rate, wastage rate, obstetrical and neonatal complications. cfDNA rate was evaluated in spent culture media and not by blastocentesis, which could provide a more accurate quantification.

Wider implications of the findings

To our knowledge, this is the first prospective randomized controlled study assessing the benefit of AS of BC before fresh blastocyst transfer. The inclusion of live birth rate is crucial to ascertain the interest of this technique and more studies are needed to improve the use of cfDNA in routine.

Trial registration number

NCT02988544

Role of Microbiota-Gut-Brain Axis in Regulating Dopaminergic Signaling

Dopamine is a neurotransmitter that plays a critical role both peripherally and centrally in vital functions such as cognition, reward, satiety, voluntary motor movements, pleasure, and motivation. Optimal dopamine bioavailability is essential for normal brain functioning and protection against the development of neurological diseases. Emerging evidence shows that gut microbiota have significant roles in maintaining adequate concentrations of dopamine via intricate, bidirectional communication known as the microbiota-gut-brain axis. The vagus nerve, immune system, hypothalamus–pituitary–adrenal axis, and microbial metabolites serve as important mediators of the reciprocal microbiota-gut-brain signaling. Furthermore, gut microbiota contain intrinsic enzymatic activity that is highly involved in dopamine metabolism, facilitating dopamine synthesis as well as its metabolite breakdown. This review examines the relationship between key genera of gut microbiota such as Prevotella, Bacteroides, Lactobacillus, Bifidobacterium, Clostridium, Enterococcus, and Ruminococcus and their effects on dopamine. The effects of gut dysbiosis on dopamine bioavailability and the subsequent impact on dopamine-related pathological conditions such as Parkinson’s disease are also discussed. Understanding the role of gut microbiota in modulating dopamine activity and bioavailability both in the periphery and in the central nervous system can help identify new therapeutic targets as well as optimize available methods to prevent, delay, or restore dopaminergic deficits in neurologic and metabolic disorders.

[Environmental endocrine disruptors and fertility]

Endocrine disruptor chemicals (EDCs) are ubiquitous contaminants in the environment, wildlife, and humans. During the last 20 years, several epidemiological, clinical and experimental studies have demonstrated the role of EDCs on the reduction of male and female fertility. The concept of foetal origins of adult disease is particularly topical in the field of reproduction. Moreover, exposure to EDCs during pregnancy has been shown to influence epigenetic programming of endocrine signalling and other important physiological pathways, and provided the basis for multi- and transgenerational transmission of adult diseases. However, the large panel of EDCs simultaneously present in the air, sol and water makes the quantification of human exposition still a challenge. Gas chromatography coupled with mass spectrometry, the measurement of total plasmatic hormonal bioactivity on stably transfected cell lines as well as the EDC analysis in hair samples are useful methods of evaluation. More recently, microRNAs analysis offers a new perspective in the comprehension of the mechanisms behind the modulation of cellular response to foetal or post-natal exposure to EDCs. They will help researchers and clinicians in identifying EDCs exposition markers and new therapeutic approaches in the future.

O-141 Mapping of SARS-CoV-2-associated receptors and proteases mRNA in human endometrium during natural and stimulated cycles

Study question

Covid-19 pandemic has significantly affected the assisted reproductive technology (ART) practice. Understanding whether SARS-CoV-2 could infect endometrial tissues during ART is crucial for risk mitigation

Summary answer

Analyses of gene expression profiles of SARS-CoV-2 host entry candidates from microarray data suggest that endometrium should be considered as potential target for SARS-CoV-2 infection.

What is known already

Very few studies analyzed the gene expression profiles of SARS-CoV-2-associated receptors and proteases, mainly focusing on ACE2 and TMPRSS2 expression, resulting incomplete knowledge in different specimens from female genital tract. However, no studies have analyzed the potential impact of controlled ovarian stimulation (COS) protocols during ART procedure on the endometrial gene expression profiles of SARS-CoV-2-associated receptors and proteases

Study design, size, duration

To address this question, we retrospectively examined the gene expression profile of SARS-CoV-2-associated receptors and proteases in endometrial biopsies of a cohort of ART candidates using Affymetrix microarray data

Participants/materials, setting, methods

Human endometrial tissue under natural (n = 62) and COS cycles (n = 42) were analyzed. A focus was particularly made on the renin-angiotensin system relates genes with a prominent role in the virus infection, and gene expression levels of receptors and proteases closely related to SARS-CoV-2 infectionwas also studied.

Main results and the role of chance

Using our large cohort of endometrial samples, we reported a high prevalence of genes related to the ACE2 pathway, including AGT, AGTR1, ANPEP, CTSA, ENPEP, LNPEP, MME, NLN, THOP1, BSG and CTSL during both phases(early- and mid-secretory phase), and mainly during the mid-secretory phase for ACE2. The highest signal intensities were found for CTSA, LNPEP, MME, NLN, BSG and CTSL. The most representative of dual coexpression of SARS-CoV-2-associated receptor and protease in endometrium was BSG-CSTL and BSG-CTSA. It s also important to note high variation of SARS-CoV-2 receptors inter-patients under natural cycle.Globally, the impact of COS on endometrial gene expression profile of SARS-CoV-2-associated receptors and proteases of non Covid-19 patients is low, suggesting no additional potential risks of SARS-CoV-2 infection during stimulated ART procedure compared with natural cycles.

Limitations, reasons for caution

Analyses of Affymetrix microarray gene expression data were performed in non-COVID-19 patients. Whether the SARS-CoV-2 infection changes the endometrial gene expression profile of SARS-CoV-2-associated receptors and proteases is under investigation

Wider implications of the findings

Specimens from female genital tract may be considered as potential targets for SARS-CoV-2.

Trial registration number

not applicable

P–242 Gene expression profiles of SARS-CoV–2-associated receptors and proteases in human early embryonic development and follicular cells

Study question

Are the oocytes, embryos, granulosa and cumulus cells, used during ART, susceptible to the SARS-CoV–2 infection?

Summary answer

Transcriptomic analyses of SARS-CoV–2-associated receptors and proteases strongly suggest that blastocysts are most permissive to SARS-CoV–2 compared with mature oocytes and day 3 embryos.

What is known already

Very few studies analyzed the gene expression profiles of SARS-CoV–2-associated receptors and proteases, mainly focusing on ACE2 and TMPRSS2 expression, resulting in partial knowledge in different specimens from female genital tract. To date, the gene expression profile of SARS-CoV–2 host entry candidates in the entire preimplantation embryos is scarcely available. Moreover, reports on oocyte and granulosa cells susceptibilityto SARS-CoV–2 are very sparse.

Study design, size, duration

To address this question, we retrospectively examined the gene expression profiles of SARS-CoV–2-associated receptors and proteases in human granulosa cells (GCs), cumulus cells (CCs), mature oocytes, day 3 embryos, blastocysts and trophectoderm cells obtained from our previously described Affymetrix microarray data.

Participants/materials, setting, methods

Human GCs and CCs (n = 17), mature oocytes (n = 6), and preimplantation embryos (n = 20) were analyzed. The comparison of gene expression levels of receptors and proteases closely related to SARS-CoV–2 infection. For each gene, the number of samples with the probe set ‘present’, based on the detection call, was analyzed. Each probe set was classified according to the signal intensity value median, as low (&lt;100), medium (100–200) or high expression level (&gt;200).

Main results and the role of chance

ACE2, BSG, CTSL, CTSA were detectable at high expression level in all mature oocyte samples, while only CTSL was strongly expressed in all day 3 embryos. The most representative dual co-expression of SARS-CoV–2-associated receptor and protease (60% of samples) during the embryonic genome activation stage (EGA) was ACE2-CTSL and BSG-CTSL. In blastocysts, ACE2, BSG, CTSL, CTSA and FURIN were detectable in the entire cohort at high expression level, and the prevalence of the different dual co-expression of SARS-CoV–2-associated proteases and receptors was optimal (100% of samples). Interestingly, only CTSL was detectable in all trophectoderm samples and a prevalence of 60% was found for the BSG-CTSL co-expression. ACE2, BSG, CTSL and CTSA were present at high expression level in CCs samples. In contrast, ACE2 and BSG expression was very low while CTSL and CTSA showed a high expression level in GCs.A prevalence of 100% was reported for ACE2-CTSL, ACE2-CTSA co-expression for both cell types. In addition, BSG-CTSL and BSG-CTSA co-expression were also present in all CCs against ∼70% in GCs samples. This data suggest a potential risks of SARS-CoV–2 infection either GC or early embryo development.

Limitations, reasons for caution

Analyses of Affymetrix microarray gene expression data were performed in non-COVID–19 patients. Whether the SARS-CoV–2 infection change the gene expression profile of SARS-CoV–2-associated receptors and proteases is under investigation.

Wider implications of the findings: Specimens from female genital tract may be considered as potential targets for SARS-CoV–2.

Trial registration number

Not applicable

[Cesarean scare niche: Definition, diagnosis, risk factors, prevention, symptoms, adverse effects, and treatments]

OBJECTIVES

To review the definitions, diagnostic methods, risk factors, symptoms, and treatments for caesarean scar niche.

METHODS

Review of the literature, critical reflection, and pragmatic advice.

RESULTS

There is no consensus on the definition of caesarean scar niche. Some suggest an indentation≥2mm of the myometrium of the caesarean scar, but this is present in more than half of women with caesarean history and takes no account of woman's symptoms. The most popular diagnostic method is ultrasound±hysterosonography. Risks factors for niche are multiple Caesareans, Cesarean during labor with too low incision, and retroverted uterus. Symptoms include abnormal gynaecologic bleeding and pelvic pain, and their presence establish the "Caesarean scar syndrome". The risks of pregnancy with niche is poorly studied, but pregnancy is not contraindicated, even if the niche is untreated. The treatment of caesarean scar niche is mainly surgery and conservative. The former should be reserved for symptomatic patients, and those with secondary infertility and fertility treatment failure. Patients with residual myometrium thickness≥2.5mm may benefit from first-line hysteroscopic treatment, whereas a laparoscopic or vaginal approach could be offered in other cases.

CONCLUSIONS

A pragmatic definition of caesarean scar niche as a disease including symptoms is the necessary prerequisite for the management of women. The treatment is mainly surgical, or conservative depending on the desire for subsequent pregnancy.

[Assessment of genital microbiota: An emerging approach in assisted reproductive techniques]

The genital microbiota actively participates in women's reproductive health. Indeed, a genital dysbiosis (microbial imbalance associated with adverse effects on host health) can lead to vaginal infections (such as mycoses or bacterial vaginosis). Recent data reported that genital dysbiosis (e.g. vaginal or endometrial) was associated with fewer chances of live births in assisted reproductive technologies (ART), via decreased pregnancy rates and an increased risk of miscarriages. The presence or diversity of certain bacterial strains (in particular Gardenellavaginalis, Proteobacteria, Lactobacillusjensenii, Lactobacilluscrispatus or Atopobiumvaginae) within the genital microbiota seem to be associated with the outcomes of ART cycles, suggesting new approaches to improve ART results. In this review, we aim at presenting the state of art on the association between the female genital microbiota and ART success. The diagnostic and therapeutic approaches (i.e. probiotics, antibiotic therapy and transplantation of vaginal microbiota) in the management of patients with altered microbiota will also be discussed. The confirmation of these data in the coming years could significantly improve the management of infertile patients in ART with a more personalized approach partially based on the female genital microbiotic profile.

[Endometrial receptivity in assisted reproductive techniques: An aspect to investigate in embryo implantation failure]

Infertility affects between 8 and 12% of reproductive-age couples worldwide. Despite improvements in assisted reproductive techniques (ART), live birth rates are still limited. In clinical practice, imaging and microscopy are currently widely used, but their diagnostic effectiveness remains limited. In research, the emergence of innovative techniques named OMICS would improve the identification of the implantation window, while progressing in the understanding of the pathophysiological mechanisms involved in embryo implantation failures. To date, transcriptomic analysis seems to be the most promising approach in clinical research. The objective of this review is to present the results obtained with the different approaches available in clinical practice and in research to assess endometrial receptivity in patients undergoing ART.

Avian Primordial Germ Cells Contribute to and Interact With the Extracellular Matrix During Early Migration

During early avian development, primordial germ cells (PGC) are highly migratory, moving from the central area pellucida of the blastoderm to the anterior extra-embryonic germinal crescent. The PGCs soon move into the forming blood vessels by intravasation and travel in the circulatory system to the genital ridges where they participate in the organogenesis of the gonads. This complex cellular migration takes place in close association with a nascent extracellular matrix that matures in a precise spatio-temporal pattern. We first compiled a list of quail matrisome genes by bioinformatic screening of human matrisome orthologs. Next, we used single cell RNA-seq analysis (scRNAseq) to determine that PGCs express numerous ECM and ECM-associated genes in early embryos. The expression of select ECM transcripts and proteins in PGCs were verified by fluorescent in situ hybridization (FISH) and immunofluorescence (IF). Live imaging of transgenic quail embryos injected with fluorescent antibodies against fibronectin and laminin, showed that germinal crescent PGCs display rapid shape changes and morphological properties such as blebbing and filopodia while surrounded by, or in close contact with, an ECM fibril meshwork that is itself in constant motion. Injection of anti-β1 integrin CSAT antibodies resulted in a reduction of mature fibronectin and laminin fibril meshwork in the germinal crescent at HH4-5 but did not alter the active motility of the PGCs or their ability to populate the germinal crescent. These results suggest that integrin β1 receptors are important, but not required, for PGCs to successfully migrate during embryonic development, but instead play a vital role in ECM fibrillogenesis and assembly.

[Comparison of birth weights of children born after slow frozen embryo replacement versus fresh embryo transfer]

OBJECTIVE

It is already known that children born after slow frozen embryo replacement have a significantly higher birth weight compared to children born after fresh embryo transfer. Similar data have been reported related to frozen embryo transfer using an open vitrification system. However, few data relative to birth weight using a complete embryo closed vitrification system has been reported. The purpose of this study was to know if frozen embryo in closed vitrification system is associated with a higher birth weight compared to fresh embryo replacement.

DESIGN

This was a monocentric retrospective cohort study, 371 children were issued from fresh embryo replacement and 127 from vitrified embryo transfer.

MATERIALS AND METHODS

All singletons born after fresh or vitrified embryo transfer between January 2011 and April 2015 were included. Births from the vitrified or fresh transfers of egg or sperm donation, and preimplantation genetic diagnosis were excluded. In addition, pregnancies with more than one gestational sac at the first ultrasound were excluded. An analysis of covariance (ANCOVA) was used for multivariate analysis.

RESULTS

Mean birth weight was 205g higher in the frozen embryo compared with fresh embryos transfer groups (3368g vs. 3163g respectively, P<0.001). This difference remained after multivariate analysis adjusted on confounding factors such as gestational age, maternal age, maternal body mass index (BMI), tobacco exposure, number of embryo transferred and birth order (P<0.001)..

CONCLUSIONS

Embryo frozen in closed vitrification system is associated with a higher birth weight compared to fresh embryo replacement. Our findings are consistent with the previous studies related to slow freezing and open vitrification systems data. The effects of controlled ovarian stimulation (COS), ex vivo culture conditions and cryopreservation systems on birth weight of children born should be further explored.

[Birth weight and frozen embryo transfer: State of the art]

The aim of this study was to update our acknowledgment if there is a link between assisted embryo cryopreservation and epigenetics in human? Animal studies have demonstrated epigenetics consequence and especially imprinting disorders due to in vitro culture. In human, it is important to note that after frozen embryo transfer birth weight is significantly increased by 81 to 250g. But these studies cannot identify the reasons of such difference. This review strongly suggests that embryo cryopreservation is responsible for birth weight variations but mechanisms not yet elucidated. Epigenetics is probably one of these but to date, none study is able to prove it. We have to be attentive on a possible link between assisted reproductive technology (ART) and epigenetics reprogrammation.

[Natural cycle for frozen-thawed embryo transfer: Spontaneous ovulation or triggering by HCG]

OBJECTIVE

To compare frozen-thawed embryo transfer (FET) outcomes in natural cycles according to ovulation induction: spontaneous versus recombinant human chorionic gonadotrophin (r-hCG) triggering.

METHODS

This retrospective study included all patients monitored for natural cycle FET during one year. When serial monitoring were performed until spontaneous LH rise, patients were included in group A (n=38) whereas those receiving r-hCG for ovulation triggering formed group B (n=43). All embryos had been cryopreserved by a vitrification method following a previous IVF cycle. No luteal phase support had been given. We compared outcomes between the 2 groups.

RESULTS

After checking groups comparability, we didn't find significant difference for the implantation rate, clinical pregnancy rate and live birth (31% vs 45%, 32% vs 51% et 21% vs 32%, respectively for group A and B). The number of monitoring was significantly lower in group B (1,9±0,8 versus 2,5±1, P=0,006).

DISCUSSION

Although no consensus has been yet established, natural cycle seems indicated for normo-ovulating patients but the question of ovulation induction is still debated. In our study, triggering ovulation by r-hCG, respecting strict criteria, seems provide good results while reducing both protocol's constraints and cost.

[Quality of oocytes and embryos from women with polycystic ovaries syndrome: State of the art]

The frequency of polycystic ovary syndrome (PCOS) and the consequent fertility disorders cause many difficulties in the management of the assisted reproductive technics. Some studies are focused on different additional treatments, stimulation protocols or techniques that could optimize the in vitro fertilization cycles. The quality of the oocytes and embryos of these patients is also an outstanding issue. They remain difficult to actually evaluate during management, and none of the few published studies on this subject demonstrated any inferiority, compared to control patients. However, many differences have been highlighted, studying intra- and extra-ovarian factors. The advent of new genetic techniques could allow a better understanding of the pathophysiological mechanisms of the syndrome, as well as refining the evaluation of oocytes and embryos, in order to better predict the results of in vitro fertilization attempts. Pregnancy and birth rates, however, appear to be comparable to those of the general population.

[Biomarkers of the cumulus cells in medically assisted procreation: State-of-the-art]

The oocyte grows within a follicle composed of layers of somatic cells. It undergoes with the cumulus cells that form the innermost layer a dialogue that is critical for its maturation. Based on the assumption that the transcriptome of the cumulus cells reflects the physiology of the oocyte, it may prove a useful non-invasive tool in embryo selection to improve assisted reproduction outcomes. During the past decade, various studies have been conducted with the objective of identifying cumulus biomarker genes as prognosis tools for oocyte quality and competence. Remarkably no common biomarkers stand out among all these studies. In this review we perform a critical analysis of the literature in order to reveal some of the parameters that may account for these discrepancies, such as patients' inclusion criteria (maternal age, stimulation protocols), day of embryo transfer (day 3 or 5), outcome criteria (oocyte potential, embryo competence, pregnancy). Moreover there is a lack of standardization in the experimental designs used for RNA extraction and gene expression assessment (microarrays, RT-qPCR) and for the statistical analyses. In conclusion, critical analyses such as the present one are indispensable to pave the way for future searches of predictive biomarkers of pregnancy.

Male infertility: an obstacle to sexuality?

Interactions between infertility and sexuality are numerous and complex. Infertile men may suffer from sexual dysfunction (SD) when undergoing an assisted reproductive technology programme. We undertook a review both in French and English of the available data on male SD when being diagnosed with a fertility problem with a specific focus on azoospermic men. The review was performed over a 30-year time period using PubMed/Medline. The sexual concerns and needs of infertile/sterile men for whom potential parenting can be compromised were evaluated. When diagnosed with infertility, men usually go through a crisis that can have a deleterious effect on their sexuality with sometimes a feeling of sexual inadequacy. Infertile men will feel stigmatized because they are perceived as being deficient in a specific component of their masculinity. Hence, subsequent SD may occur that can impact the couple sexuality and the infertility management. However, little is known on how the announcement of azoospermia may affect male on a sexual and psychological point of view. The present review suggests that a global management through a healthcare network (biologist, andrologist, sexologist and psychologist) is required which will allow to consider infertility and its subsequent sexual disorders as a whole and not as dichotomized issues.

[Comparison of frozen embryo transfer outcomes at blastocyst stage according to freezing method and type of endometrial preparation]

OBJECTIVE

This study intended to compare frozen embryo transfer (FET) outcomes at blastocyst stage according to freezing methods, slow freezing versus vitrification and according to the type of endometrial preparation.

PATIENTS AND METHODS

A total of 172 FET at blastocyst stage (day 5 or 6) were included retrospectively from April, 2007 to December, 2012. The FET outcomes from slow freezing (group 1, n=86) were compared with those from vitrification (group 2, n=86). More particularly, the survival rate after thawing, as well as implantation and pregnancy rates (clinical and ongoing pregnancy rates) were compared respectively between these two groups, after matching on women's age at freezing day, embryo number and embryo development stage for transfer. Furthermore, for each freezing method, FET outcomes were compared according to the type of endometrial preparation, i.e. natural cycle (group N) versus stimulated cycle (group S).

RESULTS

The survival rate as well as implantation and clinical pregnancy rates were significantly higher for FET after vitrification compared to FET after slow freezing (97% vs 85%, P<0.0001; 32% vs 20%, P=0.02; 43% vs 28%, P=0.04, respectively). By taking into account the number of transferred embryos for each group, the multiple pregnancy rate was three-fold higher in the group of FET after vitrification compared to the group of FET after slow freezing but not significantly (27.3% vs 8.3%, NS). However, FET outcomes were not affected significantly by the type of endometrial preparation whatever freezing methods. Nevertheless, the early spontaneous abortion (ESA) rate was lower in the case of embryos that were frozen by vitrification and transferred in natural cycle (group N2 vs group S2: 20% vs 47%, NS).

DISCUSSION AND CONCLUSION

Our study confirms that the survival rate after thawing at blastocyst stage (day 5 or 6) is significantly improved after freezing by vitrification compared to slow freezing method. Likewise, implantation and clinical pregnancy rates are significantly increased in the case of FET at blastocyst stage when these embryos were frozen by vitrification. The results obtained by vitrification are very satisfactory but are also associated with an increased multiple pregnancy rate. Moreover, FET associated with natural or stimulated cycle does not modify significantly the outcomes of attempts, whatever the freezing method. However, the risk of ESA is reduced in the case of FET with natural cycle and after embryo vitrification.

Developmental regulated expression of anti- and pro-apoptotic BCL-2 family genes during human early embryonic development

Apoptotic cell death has been reported in human oocytes and preimplantation embryos under in vivo and in vitro conditions. BCL-2 family proteins comprise both anti- and pro-apoptotic members, which are likely to play a key role in controlling oocyte and early embryo survival. However, very limited data are available on their expression kinetics during human early embryonic development. Using our DNA microarray data, we analyzed the expression pattern of 21 BCL-2 family genes in human mature MII oocytes, day 3 embryos and day 5/6 blastocysts from patients who underwent in vitro fertilization (IVF). Selected genes were further validated by qRT-PCR and their subcellular localization analyzed by immunofluorescence confocal microscopy. Our results suggest a switch from oocyte-inherited BCL-2 family transcripts, such as BCL2L10, to embryo-produced transcripts after embryonic genome activation, including BIK, BCL2L11 and NOXA. Moreover, the pro-apoptotic gene BCL2L13 was constitutively expressed throughout human early embryonic development. Remarkably, day 3 embryos expressed more BCL-2 pro-apoptotic genes than mature MII oocytes and day 5/6 blastocysts, suggesting that embryos at this stage are more prone to apoptosis. This is further supported by an absence of cleaved Caspase-3 in the oocyte and its presence in the embryo. Using a drug that induces apoptosis (gambogic acid), we were able to show activated Caspase-3 in the oocyte in addition to an alteration of BCL2L13 protein localization. Similarly BCL2L13 localization was altered in degenerated oocytes. This study opens new perspectives for understanding the molecular regulation of human oocyte and pre-implantation embryo survival and death.

[Effects of artificial shrinkage prior to vitrification in a closed system: a randomized controlled trial]

OBJECTIVE

To evaluate the effect of induced blastocoele shrinkage before vitrification in a closed carrier device.

PATIENTS AND METHODS

Prior to vitrification, blastocyst cavity was artificially shrinked by laser pulse or not treated according to a 2:1 randomized procedure. A total of 185 warming cycles from April 2011 to March 2013 have been analyzed. Clinical pregnancy rate and survival rate were compared between the two groups. The mean (±SD) women age was 33.5±5.7 years for both groups.

RESULTS

The pregnancy rate in the group with artificial reduction of the cavity was higher ([32/67] 47.7%) than in the control group but not significantly ([43/113] 38%). The survival rate in the artificial shrinkage group was significantly higher compared with the control group : 99% (102/103) and 91.8% (168/183) respectively (P=0.01).

DISCUSSION AND CONCLUSION

This study reveals that artificial shrinkage of blastocoelic cavity by laser pulse before vitrification in a closed carrier device improves survival rate after warming.

[Oncofertility program at the Montpellier university hospital 2 years after]

OBJECTIVE

Female fertility preservation in the context of cancer management is crucial for patient's health care. The aim of this study was to evaluate the oncofertility practice at our university hospital of Montpellier since 2011.

PATIENTS AND METHODS

The evaluation of management of young patients referred to Montpellier University Hospital from September 2011 to September 2013 for oncofertility counselling before cancer treatment.

RESULTS

Seventy-one patients were referred to a specialized oncofertility center. Forty-two patients (59.1%) were included in the oncofertility program. Twenty-two patients (31%) were proposed for oocyte vitrification after COS protocol, eight patients (11.3%) for ovarian tissue cryoconservation, seven patients (9.9%) for GnRH injections, three patients (4.2%) ovarian transposition and two patients (2.8%) for embryo cryopreservation. Among the 42 indications of fertility preservation, only 18 will have finally taken place.

CONCLUSION

Oncofertility counselling for young patients should now be part of the cancer management. It involves multidisciplinary teams. Further information of both oncologists and patients is needed to improve this new approach in the field of cancer treatments.