Paternal Age Amplifies Cryopreservation-Induced Stress in Human Spermatozoa

The global fall in male fertility is a complicated process driven by a variety of factors, including environmental exposure, lifestyle, obesity, stress, and aging. The availability of assisted reproductive technology (ART) has allowed older couples to conceive, increasing the average paternal age at first childbirth. Advanced paternal age (APA), most often considered male age ≥40, has been described to impact several aspects of male reproductive physiology. In this prospective cohort study including 200 normozoospermic patients, 105 of whom were ≤35 years (non-APA), and 95 of whom were ≥42 years (APA), we assessed the impact of paternal age on different endpoints representative of sperm quality and cryopreservation tolerance. Non-APA patients had superior fresh semen quality; DNA fragmentation was notably increased in APA as compared to non-APA individuals (21.7% vs. 15.4%). Cryopreservation further increased the DNA fragmentation index in APA (26.7%) but not in non-APA patients. Additionally, APA was associated with increased mtDNAcn in both fresh and frozen/thawed sperm, which is indicative of poorer mitochondrial quality. Cryopreservation negatively impacted acrosome integrity in both age groups, as indicated by reduced incidences of unreacted acrosome in relation to fresh counterparts in non-APA (from 71.5% to 57.7%) and APA patients (from 75% to 63%). Finally, cryopreservation significantly reduced the phosphorylation status of proteins containing tyrosine residues in sperm from young males. Therefore, the present findings shed light on the effects of paternal age and cryopreservation on sperm quality and serve as valuable new parameters to improve our understanding of the mechanisms underlying sperm developmental competence that are under threat in current ART practice.

Exposure to Cumulus Cell Secretome Improves Sperm Function: New Perspectives for Sperm Selection In Vitro

In the literature, there is a well-known correlation between poor semen quality and DNA sperm integrity, which can turn into negative outcomes in terms of embryo development and clinical pregnancy. Sperm selection plays a pivotal role in clinical practice, and the most widely used methods are mainly based on sperm motility and morphology. The cumulus oophorus complex (COC) during natural fertilization represents a barrier that spermatozoa must overcome to reach the zona pellucida and fertilize the oocyte. Spermatozoa that can pass through the COC have better structural and metabolic characteristics as well as enhanced acrosome reaction (AR). The present study aimed to evaluate the exposure of sperm to cumulus cell secretome during swim-up treatment (SUC) compared with the routinely used swim-up method (SU). To determine the effectiveness of this method, biological factors critical for the ability of sperm to fertilize an oocyte, including capacitation, AR, tyrosine phosphorylation signature, DNA integrity, and mitochondrial functionality, were assessed. The SUC selection assures recovery of high-quality spermatozoa, with enhanced mitochondrial functionality and motility compared with both SU-selected and unselected (U) sperm. Furthermore, using this modified swim-up procedure, significantly reduced sperm DNA damage (p < 0.05) was detected. In conclusion, the SUC approach is a more physiological and integrated method for sperm selection that deserves further investigation for its translation into clinical practice.

Case report: The CCDC103 variant causes ultrastructural sperm axonemal defects and total sperm immotility in a professional athlete without primary ciliary diskinesia

Primary ciliary dyskinesia (PCD) is an inherited autosomal-recessive disorder characterized by abnormal ciliary motion, due to a defect in ciliary structure and/or function. This genetic condition leads to recurrent upper and lower respiratory infections, bronchiectasis, laterality defect, and subfertility. Male infertility is often associated with PCD, since the ultrastructure of the axoneme in the sperm tail is similar to that of the motile cilia of respiratory cells. We present the first reported case of a male patient from a non-consanguineous Italian family who exhibited a severe form of asthenozoospermia factor infertility but no situs inversus and absolutely no signs of the clinical respiratory phenotype, the proband being a professional basketball player. Whole-exome sequencing (WES) has identified a homozygote mutation (CCDC103 c.461 A>C, p.His154Pro) in the proband, while his brother was a heterozygous carrier for this mutation. Morphological and ultrastructural analyses of the axoneme in the sperm flagellum demonstrated the complete loss of both the inner and outer dynein arms (IDA and ODA, respectively). Moreover, immunofluorescence of DNAH1, which is used to check the assembly of IDA, and DNAH5, which labels ODA, demonstrated that these complexes are absent along the full length of the flagella in the spermatozoa from the proband, which was consistent with the IDA and ODA defects observed. Noteworthy, TEM analysis of the axoneme from respiratory cilia showed that dynein arms, although either IDAs and/or ODAs seldom missing on some doublets, are still partly present in each observed section. This case reports the total sperm immotility associated with the CCDC103 p.His154Pro mutation in a man with a normal respiratory phenotype and enriches the variant spectrum of ccdc103 variants and the associated clinical phenotypes in PCD, thus improving counseling of patients about their fertility and possible targeted treatments.

3D model of the maternal-fetal interface: challenges, recent advances and beyond

Embryo implantation is a complex and highly coordinated process that involves an intricate network of factors establishing intimate contact at the maternal-fetal interface. Knowledge of the human implantation process is compromised by both ethical issues, which do not allow the study of this process in vivo, and by the accuracy and reproducibility of in vitro models of human endometrium. Effective and reliable embryo implantation models are, therefore, necessary to mimic the molecular event cascade that occurs in vivo. 3D models are considered a new step to foster precision medicine and an advanced tool for the study of endometrial biology, endometrium associated diseases and to understand the complex mechanisms surrounding endometrium-embryo crosstalk. In this review we explore the various methods by which 3D cultures of endometrium and trophoblast can be created, exploring targets and applications of these in vitro models.

Bitter Taste Receptors and Endocrine Disruptors: Cellular and Molecular Insights from an In Vitro Model of Human Granulosa Cells

Endocrine disrupting chemicals (EDCs) are compounds that interfere with the synthesis, transport and binding action of hormones responsible for reproduction and homeostasis. Some EDCs compounds are activators of Taste bitter Receptors, a subclass of taste receptors expressed in many extraoral locations, including sperm and follicular somatic cells. This makes TAS2Rs attractive molecules to study and investigate to shed light on the effect of EDCs on female reproduction and fertility. This study aims to assess the effect of selected EDCs [namely Biochanin A (BCA), caffeine, Daidzein, Genistein and Isoflavone] on hGL5, an immortalized cell line exhibiting characteristics coherent with primary follicular granulosa cells. After demonstrating that this model expresses all the TAS2Rs (TAS2R3, TAS2R4, TAS2R14, TAS2R19, TAS2R43) specifically expressed by the primary human granulosa cells, we demonstrated that BCA and caffeine significantly affect mitochondrial footprint and intracellular lipid content, indicating their contribution in steroidogenesis. Our results showed that bitter taste receptors may be involved in steroidogenesis, thus suggesting an appealing mechanism by which these compounds affect the female reproductive system.

Neurodegenerative Disorder Risk in Krabbe Disease Carriers

Krabbe disease (KD) is a rare autosomal recessive disorder caused by mutations in the galactocerebrosidase gene (GALC). Defective GALC causes aberrant metabolism of galactolipids present almost exclusively in myelin, with consequent demyelinization and neurodegeneration of the central and peripheral nervous system (NS). KD shares some similar features with other neuropathies and heterozygous carriers of GALC mutations are emerging with an increased risk in developing NS disorders. In this work, we set out to identify possible variations in the proteomic profile of KD-carrier brain to identify altered pathways that may imbalance its homeostasis and that may be associated with neurological disorders. The differential analysis performed on whole brains from 33-day-old twitcher (galc ^−/−), heterozygous (galc ^+/−), and wild-type mice highlighted the dysregulation of several multifunctional factors in both heterozygous and twitcher mice. Notably, the KD-carrier mouse, despite its normal phenotype, presents the deregulation of vimentin, receptor of activated protein C kinase 1 (RACK1), myelin basic protein (MBP), 2′,3′-cyclic-nucleotide 3′-phosphodiesterase (CNP), transitional endoplasmic reticulum ATPase (VCP), and N-myc downstream regulated gene 1 protein (NDRG1) as well as changes in the ubiquitinated-protein pattern. Our findings suggest the carrier may be affected by dysfunctions classically associated with neurodegeneration: (i) alteration of (mechano) signaling and intracellular trafficking, (ii) a generalized affection of proteostasis and lipid metabolism, with possible defects in myelin composition and turnover, and (iii) mitochondrion and energy supply dysfunctions.

Cellular and Molecular Mechanisms of In Vivo and In Vitro SARS-CoV-2 Infection: A Lesson from Human Sperm

Despite the major target of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, being the respiratory system, clinical evidence suggests that the male reproductive system may represent another viral target organ. Revealing the effect of SARS-CoV-2 infection on testis and sperm is a priority for reproductive biology, as well as for reproductive medicine. Here, we confirmed that the SARS-CoV-2 receptor angiotensin-converting enzyme 2 (ACE2) is highly expressed on human testis and ejaculated sperm; moreover, we provide evidence for the expression of the co-receptors transmembrane protease/serine (TMPRSS2), Basigin (BSG), and Catepsin L (CTSL). Human sperm were readily infected, both in vivo and in vitro, by SARS-CoV-2, as demonstrated by confocal and electron microscopy. The demonstration that the seminiferous epithelium and sperm support SARS-CoV-2 viral replication suggests the possibility that the spermatogenetic process may be detrimentally affected by the virus, and at the same time, supports the need to implement safety measures and guidelines to ensure specific care in reproductive medicine.

P-460 SARS-CoV-2 infection of human ovarian cells: an in vitro model for the detection of the virus entry into the host cells

Study question

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can enter and actively infect human follicular and granulosa cells?

Summary answer

Follicular Granulosa (GCs) and Cumulus cells (CCs) are susceptible to SARS-CoV-2 infection that is able to reproduce.

What is known already

To enter host cells, SARS-CoV-2 uses Spike S1 subunit to bind the receptor angiotensin-converting enzyme2 (ACE2), S2 subunit is cleaved by the host transmembrane serine protease 2 (TMPRSS2) or by cathepsin L (CSTL) to produce unlocked, fusion-catalyzing viral forms. CD147 (BSG) has been proposed as an additional host receptor for SARS-CoV-2. Female fertility is strictly dependent on oocyte quality and competence. ACE2 is highly expressed in the human ovaries and in the stromal endometrial cells, as well as in GCs and oocytes. The expression of ACE2 strongly suggests that it is potentially at a high risk of SARS-CoV-2 infection.

Study design, size, duration

In order to analyze the presence of host receptors ACE2 and co-receptors TMPRSS2-CSTL and BSG and consequently the susceptibility of GCs and CCs to SARS-CoV2 infection. GCs and CCs were collected from about 25 patients undergoing IVF/ICSI cycles at the UOSA of Assisted Reproductive techniques, from March 2020 to October 2021 at the Center of Couple Sterility, Siena University Hospital.

Participants/materials, setting, methods

GCs and CCs were collected from women undergoing IVF cycle. GCs were recovered from the follicular fluid according to the procedure previously published. After oocyte denuding, CCs were isolated and both GCs and CCs co-cultured with SARS-CoV-2 then the supernatant was used to infect VERO6 Cells. Host factors and SARS-CoV2 expression/localization were confirmed by RT-PCR, Western blot and Immunofluorescence. SARS-CoV2 infection and its effect on GCs and CCs were evaluated by Transmission and Immuno-electron microscopy.

Main results and the role of chance

qRT-PCR analysis and WB showed that ACE2, TMPRSS2, BSG and CTSL transcripts were expressed in both GCs and CCs cells, even if at different levels. ACE2 transcript was significantly increased in the CCs (0.43 vs 0.15; p < 0.05) with respect to GCs; this datum is very interesting since CCs are the follicular cells able to establish intimate connections with the developing oocyte (e.g. gap junctions). Therefore, contrary to what can be assumed, human CCs cannot act as a barrier against virus entry into the oocyte. Coreceptor BSG and CTSL were the most expressed in GCs with respect to TMPRSS2, (0.7 vs 0.3 and 0.8 vs 0.4 respectively; p < 0.05). Ultrastructural evaluation of human GCs and CCs infected with SARS-CoV-2 was carried out at different time points post-infection (24h, 48h and 72h). Infected human GCs showed cell-associated virus-like particles, virions were approximately spherical, with a diameter outside the lipid bilayer ranging from 50-150 nm and ultrastructural characteristics consistent with those described for other coronaviruses. Complete virions were also observed inside the cytoplasm as single or small groups of particles, either dispersed or within large vesicles. Immunoelectron microscopy confirmed these particles as SARS-CoV2.

Limitations, reasons for caution

This is a human in vitro study, and we cannot predict all the implications in female fertility and related to the oocyte

Wider implications of the findings

We provide evidence in favor of SARS-CoV-2 infection in GCs and CCs, the ovarian somatic cells that support oocyte development and competence acquisition. The close relationship between oocytes and follicular cells raises the hypothesis that these cells may represent a vehicle for the oocyte SARS-CoV-2 infection

Trial registration number

Not applicable

P-801 Human endometrial Organoids (hEOs): a non invasive powerful tool to study receptivity and a step forward precision medicine in IVF

Study question

Organoids from menstrual blood (MB) can mimic human receptive endometrium?

Summary answer

This research provides a reliable and less invasive 3D endometrial model able to mimic the window of implantation (WOI).

What is known already

Investigating the physiology and function of the normal cycling endometrium is challenging due to its great individual variability. hEOs are considered a new step forward in precision medicine and a tool for the study of endometrial biology, associated diseases (i.e. endometriosis) and to understand the complex mechanism surrounding endometrium-embryo cross talk. During the WOI apical cytoplasmic protrusions traditionally called “pinopodes” are reported to be a specific marker of endometrial receptivity.Initially hypothesized to form at the sites of blastocyst attachment, pinopodes have typically been correlated with successful implantation and are strongly regulated by the ovarian steroid hormones.

Study design, size, duration

hEOs are usually obtained from endometrial biopsy, here a much less invasive source was employed. Menstrual blood (MB) retrieved by menstrual cups was processed to isolate epithelial (Ep) and stromal endometrial cells (hESC). hEOswere created to investigate the morphological changes occurring in vivo during the menstrual cycle, specifically at the WOI. For a proof of concept, we recruited five healthy volunteers from January 2021 to december 2022 signing an informed written consent for this study.

Participants/materials, setting, methods

All the participants provided written informed consent for the use of their MB samples. Female healthy volunteers received instruction for the use of menstrual cups. hEOs obtained from MB have been exposed to hormonal treatments to mimic the endometrial hormonal milieu typical of the proliferative and mid secretory phase of the menstrual cycle. Cultured hEOs were then observed in a Quanta 400 (FEI) scanning electron microscope (SEM).

Main results and the role of chance

In this study we succeeded to establish a reliable 3Dmodel using both Ep cells and hESC using a less invasive approach. The hEOs generated from the co-culture of these two types of cells were used to mimic the mid secretory phase. The expansion media has been supplemented with 10 − 8 M E2 + 10 − 6 M P4 and 50 mM cAMP. Treated hEOs have been cultured for 4 days; washed with PBS and fixed for 2 h at 4 °C in cold Karnovsky’s. Using Scanning electron Microscopy, we closely observed the luminal surface of hEOs in the proliferative phase. The inner side of Ep cells was characterized by the presence of pinopodes large 5-10 μm, apical plasma membrane of uterine epithelial cells protrusions, not present in unstimulated hEOs. Generally, during days 17-19 of the menstrual cycle, cellular bulging increases with the formation of small (1-2 μm) pinopodes. Their full development was reported to be present at day 20and is a specific marker of the WOI.

Limitations, reasons for caution

There are discrepancies in the literature regarding pinopode morphology on specific days of the cycle, and of course, these changes may vary between individuals. Further studies, comprising individuals undergoing IVF treatments should be explored.

Wider implications of the findings

Effective and reliable embryo implantation modeling is necessary to mimic the molecular event cascade that occurs in vivo. Pinopodes responds to stimuli, in particular to Progesterone, these findings can be used to calibrate hormonal treatments of women undergoing IVF.

Trial registration number

Not applicable

P-073 SARS-CoV2 infection in human testis and sperm: in vivo and in vitro studies

Study question

Can severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) enter somatic and germinal cells of human testis or ejaculated sperm, thus affecting male reproductive function?

Summary answer

This research provides a biological background of the potential route for infection of SARS-CoV-2 and may enable rapid deciphering of COVID-19-induced male-related reproductive disorders.

What is known already

Epidemiologic studies suggest a significant male sex susceptibility for severe COVID19 symptoms. SARS-CoV-2 is known to affect certain cell types based on their expression of angiotensin-converting enzyme 2 (ACE2) and Transmembrane serine protease2 (TMPRSS2). ACE2 makes available the binding site for the Spike protein of SARS-CoV-2. TMPRSS2 facilitates virus entry by cleaving the S antigen into S1 (the active binding site). Several studies reported the presence of ACE2 in Leydig and Sertoli cells as well as in germ cells from spermatogonia to spermatozoa. These data suggest that the human testis and gametes are a target for SARS-CoV-2.

Study design, size, duration

To address this question, we examined the gene expression profile of SARS-CoV-2-associated receptors and proteases (ACE2-TMPRSS2) as well as their protein expression and localization in testicular tissue of males undergoing diagnostic surgery and in sperm of healthy, normozoospermic donors referring to the Unit of Assisted Reproduction, Siena University Hospital, from April 2020 to January 2022.

Participants/materials, setting, methods

Assays were performed on tissue biopsies (n = 3) or on freshly ejaculated sperm of men (n = 6) undergoing routine semen analysis after granting informed consent. To this end, tissue biopsies and ejaculated sperm have been co-cultivated for 5-12h with infected VERO E6 cells. Immunoelectron microscopy, in situ hybridization, and highly sensitive digital droplet PCR analysis, have been used to assess if particles containing SARS-CoV- 2 antigens can be detected in testicular tissue or spermatozoa in vitro.

Main results and the role of chance

We carefully investigated the presence of the SARS-CoV-2 virus and the possible effect on male fertility, both at the molecular and ultrastructural levels. To elucidate the mechanisms underlying virus infection in germ cells and male gametes, we analyzed the expression of both ACE2 and TMPRSS2. Both genes are expressed in testes and ejaculated sperm, confirming the possibility that SARS-CoV2 can enter these cells. We also provided evidence of the expression of the corresponding proteins in both testis and sperm by immunofluorescence assays. The immunofluorescence staining of paraffin-embedded slices of testicular tissue with anti-ACE2 antibody revealed a strong signal in Leydig cells. However, ACE2 staining was also present in human Sertoli cells and was concentrated in the adluminal half of the cell, i.e. surrounding spermatocytes and spermatids.

The analysis of TRPMSS2 showed similar results. Indeed, this protease is localized mainly in the interstitium, at the level of Leydig cells. This is an intriguing datum, since, while Leydig cells may be considered as a high-risk cells because of the co-expression of TMPRSS2 and ACE2, germ cells may not be at increased risk of ACE2and TMPRSS2-mediated viral entry and spread, given the lack of co-expression in these testicular cell type.

Limitations, reasons for caution

The low number of analyzed samples may limit the statistical power of this study. Whether the SARS-CoV-2 infection change the gene expression profile of other SARS-CoV-2-associated proteases is under investigation

Wider implications of the findings

This validated RT-PCR assay allows reliable screening of SARS-CoV-2 in sperm, useful for investigating the presence of the virus in patients undergoing ART, as well as for explaining the molecular and cellular mechanisms related to the gender specificity of the more severe infection-related symptoms.

Trial registration number

Not applicable

P-089 Characterization of Epididymosomes and Prostasomes in Seminal Plasma of Infertile Males

Study question

Could Extracellular Vesicles such as Epididymosomes and Prostasomes be employed as a new tool to characterize the male fertility potential?

Summary answer

Extracellular vesicles (EVs) content represents a new approach to the discovery of novel molecular mechanisms involved in sperm cell maturation and acquisition of fertilizing ability.

What is known already

Cells throughout the reproductive tract release EVs that are sorted by the endosomal compartment. These vesicles attract great attention because they contain lipids, proteins, nucleic acids that have been shown to be transferred to maturing sperm cells. EVs in seminal plasma, such as epididymosomes and prostasomes, contribute about 3% of the total associated seminal plasma proteins and are recognized as being responsible for sperm maturation, positively influencing actual fertilization. Several studies have documented the proteomic profile of these vesicles, but little is known about their specific contribution to sperm maturation, motility and acquisition of fertilizing capacity.

Study design, size, duration

48 Caucasian males underwent semen evaluation at the IVF Unit, Siena University Hospital, from October 2020 to November 2021. According to seminal parameters (WHO,2010), they were divided into Normozoospermic (N; n = 18); OligoAsthenoTeratozoospermic (OAT; n = 15); Azoospermic (A; n = 15). We excluded patients with an intake of spermiotoxic drugs, smoking, alcohol, or drugs abuse. The mean age was 33 years; the BMI ranged between 18-25. All participants signed a written informed consent, approved by the ethics committee.

Participants/materials, setting, methods

EVs from seminal plasma were isolated by an in-house modified EvGAG®-polymer precipitation-based protocol and characterized for their size and morphology by Nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM), respectively. Full proteomic profiling of these vesicles was obtained by 2-D electrophoresis and mass spectrometry, and further investigations by functional Omics analysis by bioinformatic tools (as. Metacore, STRING). Gene expression was evaluated by digital PCR (ddPCR).

Main results and the role of chance

The present work highlights the impact of EVs on male fertility due to their ability to transport selected molecules to maturing sperm cells, thus providing a specific proteomic and transcriptomic profile based on their fertilizing capacity. Proteomic profiling of OAT and A vs N samples provided crucial information regarding differential protein expression, thus obtaining information on the correlation between the encapsulated content of EVs and sperm parameters.

The ddPCR analysis of specific genes encoding for proteins expressed differently among patients confirmed that EVs may not only be potential biomarkers for male infertility, but at the same time contribute as an important regulator of specific pathways concerning sperm cell modification through the male reproductive tract. Genes involved in sperm-egg binding and zona pellucida interactions were overexpressed in N compared to OAT and A. Congruent results were obtained for genes involved in sperm cell metabolism. Meanwhile, regarding the acquisition of motility, some genes were found overexpressed in the OAT groups compared to N, indicating that some proteins delivered by EVs have a negative impact on sperm cell motility and function.

Limitations, reasons for caution

This study represents a preliminary experiment. A confirmatory study on an enlarged number of samples is needed to provide more statistical strength by reducing the effect of inter-sample variability.

Wider implications of the findings

Seminal extracellular vesicles secreted along the male reproductive tract have been demonstrated to be involved in the process of sperm maturation and could represent a new appealing therapeutic and diagnostic tool in the field of human reproduction for male fertility/infertility.

Trial registration number

Not applicable

Positive Effect of a New Combination of Antioxidants and Natural Hormone Stimulants for the Treatment of Oligoasthenoteratozoospermia

Oligoasthenoteratozoospermia (OAT) accounts for about 90% of male infertility; in many cases this disorder may be associated with oxidative stress, a condition that decreases the success of fertilization. Therefore, the empirical treatment of male infertility is often based on the use of antioxidants. The aim of the present study was to assess the effectiveness of three months’ administration of a new nutraceutical preparation on hormone profile, sperm parameters and fertilization capability in men undergoing in vitro fertilization (IVF). A total of 36 OAT patients were daily treated for 3 months with a dose of a formulation containing: Inositol, L-Carnitine, Vitamins C, D, E, Coenzyme Q10 and Selenium. Selected parameters were analysed before (T0) and after (T1) treatment, and IVF outcomes were evaluated. We observed an improvement of sperm concentration, motility, morphology and vitality; blood level of testosterone also showed an increase. A significant increase of fertilization rate was detected in 14 couples, whose male partner were treated with the nutraceutical preparation. The present results indicate that a formulation containing antioxidant and energy supply substances was effective in the treatment of sperm alterations and led to significant recovery of fertilizing capacity.

Oxidative Stress Measurement in Frozen/Thawed Human Sperm: The Protective Role of an In Vitro Treatment with Myo-Inositol

Despite its widespread use, sperm cryopreservation induces serious detrimental alterations in sperm function; indeed, it is commonly associated with decreased sperm viability and motility, and DNA fragmentation. Mechanisms of human sperm cryodamage are thought to be multifactorial, but oxidative stress seems to have a prominent role. A huge amount of data supported the cryoprotective effect of different antioxidants able to minimize the detrimental effects of reactive oxygen species (ROS) and improve the quality of spermatozoa. Among others, myo-inositol is one of the most powerful and has been reported to be effective in improving sperm quality and motility when used both in vivo and in vitro. This study aimed to determine the in vitro impact of myo-inositol in ameliorating sperm oxidative status during sperm cryopreservation. In particular, we demonstrated a significant improvement of sperm parameters (vitality and motility) when myo-inositol was added after sperm thawing (p < 0.05). Moreover, we showed that myo-inositol induces a significant increase in oxygen consumption, the main index of oxidative phosphorylation efficiency and ATP production. Finally, by means of 2D-electrophoresis, we demonstrated a significant decrease in the level of carbonyl groups, the main structural changes occurring in conditions of oxidative stress (p < 0.05). In conclusion, the sperm cryopreservation procedure we developed, assuring the reduction of ROS-induced sperm modifications, may improve the in vitro procedure currently used in ART laboratory for sperm cryostorage.

O-217 Bitter Taste Receptors expression in human follicular cells: new perspectives in female fertility

Study question

Bitter TasteReceptors (TAS2Rs)role in female reproductive system cells: potential implications in mechanisms underlying oocyte maturation and sperm-oocytes interaction.

Summary answer

TAS2Rs and genes involved in their transduction cascade are differentially expressed in granulosa (GCs)and cumulus cells(CCs).

What is known already

TASRs expression can be found also in extraoral location wherein their function appears less obvious. TASRs are reported to be involved in signal transduction cascade induced by chemotactic activation in spermatozoa and the expression of TAS2Rs in ejaculated human sperm has been demonstrated. The presence of these receptors in male reproductive system and in sperm gives cues to investigate their possible role in sperm-oocyte interaction. Functional implications have been collected indicating that taste receptors are also important to increase the number of highly fertilization-competent sperm cells within the female genital tract hypothesizing a role in the field of female reproduction.

Study design, size, duration

We enrolled for this study 30patients undergoing IVF cycles because of couple infertilityfrom June 2019 to October 2020at the UOSA of Assisted Reproductive techniques, Siena University Hospital(Italy).

Participants/materials, setting, methods

Female patients referring to UOSA of Assisted Reproductive techniques(median age 35 years) underwent a personalised controlled ovarian hyperstimulation protocol. After oocyte pickup, GCs were isolated from the follicular fluid through differential gradient. CCs were collected after oocytes denuding. TAS2Rs and genes involved in the transduction cascade elicited expression/localization in both GCs and CCs were confirmed by Droplet Digital PCR, western blot andimmunofluorescence.

Main results and the role of chance

For the first time, the expression and cellular localization of the TAS2Rs (TAS2R3, TAS2R4, TAS2R14, TAS2R19 and TAS2R43), their G-coupled proteins (GNAT1 orα-transducinandGNAT3 or α-gustducin) and enzymes involved in the transduction signal (PDE4A, TRPM5 and PLCB2)were demonstrated in the female reproductive system. Overall expression of TAS2Rs emerged higher in GCs than in CCs, confirming the specific molecular fingerprinting during differentiation of ovarian somatic cells. TAS2R14 is the most expressed gene in both GCs and CCs, this could account for its potential involvement in follicular cells physiology and/or for a key role of this receptor in fertilization, as supported by data showing TAS2R14 to be correlated with sperm progressive motility. We demonstrated a positive correlation in GCs between the expression of the TAS2Rs and GNAT3; interestingly, when each subset of TAS2Rs genes was correlated with the signaling gene, TAS2R14 emerged as the one with the higher correlation with GNAT3. Immunofluorescence showed different localization of TAS2Rs and their G-coupled proteins between GCs and CCs. Interestingly some of them presented some fluorescent granules, suggesting a possible involvement of proteins in membrane trafficking. Finally, results of G-coupled proteins western blot, revealed the higher expression of α-gustducin then α-transducin, confirming the gene expression.

Limitations, reasons for caution

All findings have to be validated in a larger cohort. Moreover, our data pave the way to the understanding of biological functions exerted by these receptors in the female reproductive tract.

Wider implications of the findings

Further studies might contribute to better understanding the physiologic role of taste receptorsfemale reproductive system. This should becrucial to clarify the role of these receptors in maturation or competence acquiring of oocytes, or also in sperm-oocytes attraction and recognition, crucial point in fertilization process

Trial registration number

Not applicable

P–026 Seminal plasma exosomes: a promising source of biomarkers for fertility evaluation

Study question

Do exosomes from seminal plasma have a role in male fertility?

Summary answer

Exosomes isolated from seminal plasma have a pivotal role during spermatogenesis and sperm maturation and may represent eligible biomarkers for male fertility/infertility.

What is known already

During their journey along the male reproductive tract, exosomes contained in seminal fluid are involved in the transfer of several molecules to the maturing sperm. Exosomes are extracellular vesicles (EVs) released by all the cells; they carry a cargo of nucleic acids, proteins and lipids. In the male genital tract, they are released at various levels and their composition differs between men of proven fertility and infertile male patients. Recent studies reported the proteomic profile of exosomes, revealing the presence of several proteins with a well know role in sperm maturation and fertilizing ability acquiring.

Study design, size, duration

This prospective study consisted of 36 Caucasian men; according to seminal parameters (WHO 2010) they were divided in normozoospermic (N; n = 12), oligoasthenoteratozoospermic (OAT: n = 12) and azoospermic (A; n = 12). Semen samples were collected between October 2020 and January 2021 at the Assisted Reproductive Unit, Siena University Hospital (Italy) after institutional ethical approval and signed written consent from all the participants.

Participants/materials, setting, methods

Ejaculated sperm were analyzed according to WHO–2010 criteria and divided into the three groups: N, OAT and A. Exosomes were isolated by an in-house modified ExoGAG®-polymer precipitation-based protocol and characterized for size and ultrastructure by Nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM). The exosomal proteins were extracted and analyzed by 2D-electrophoresis and the identified profiles were examined by applying bioinformatic tools. The expression of selected genes was evaluated by digital droplets PCR (ddPCR).

Main results and the role of chance

The present work is readily providing an improvement of the standard ExoGAG® protocol and underlines its advantages over more conventional EVs isolation protocols used to date for recovery from seminal fluid: the number of recovered EVs and their size were finely included in the range of exosomes.

This isolation protocol provides samples suitable for proteomic analyses, representing the first 2D-electrophoresis reference map of exosome-pay loaded proteins in N respect to OAT/A groups and providing an innovative and comprehensive functional overview of its proteins. Moreover, the STRING protein-protein interaction analysis revealed the deregulation of specific pathways (e.g. signaling proteins, chromatin packaging and/or remodeling, protein folding and apoptosis) in A and OAT in comparison with N group.

Gene expression by ddPCR analysis highlighted that most of the analyzed genes are modulated in according to seminal parameters, in particular: GAPDHS (Glyceraldehyde–3-Phosphate Dehydrogenase, Spermatogenic); SPAM1 (Sperm Adhesion Molecule–1) encoding a members of hyaluronidase family; ADAM2 (ADAM Metallopeptidase Domain–2) that plays an important role in sperm-egg interactions; CRISP1,2,3 (Cysteine Rich Secretory Protein 1,2,3) expressed in the epididymis and secreted into the epididymal lumen; CLGN (Calmegin) encoding a testis-specific chaperone protein and PGK2 (Phosphoglycerate Kinase–2) expressed in the later stages of spermatogenesis.

Limitations, reasons for caution

This study represents a preliminary experiment. We suggest further comparative studies in larger study cohorts.

Wider implications of the findings: This pilot study, demonstrating the unique proteomic and transcriptomic pattern of exosomes in N/OAT/A groups, supports the importance of exosomes in sperm production and maturation. This methodological set-up is expected to open new ways for advancement in the use of exosomes as fertility biomarkers, making possible personalized approaches in ART.

Trial registration number

Not applicable

Extracellular matrix remodeling and inflammatory pathway in human endometrium: insights from uterine leiomyomas

OBJECTIVE

To compare the expression profiles of matrix metalloproteinases (MMPs) and their inhibitors (tissue inhibitors of matrix metalloproteinases, TIMPs) in the endometrium of women with and without type 3 leiomyomas and to understand their relationship with inflammatory status.

DESIGN

Molecular and in silico studies.

SETTING

University hospital.

PATIENT(S)

Patients with type 3 leiomyomas ranging from 3 to 10 cm in diameter (n = 18) and control age-matched women undergoing surgery for ovarian cysts (n = 18) who underwent endometrial biopsies.

INTERVENTION(S)

Endometrial biopsies.

MAIN OUTCOME MEASURE(S)

To evaluate the expression levels of MMPs and TIMPs in the endometrium, quantitative reverse transcriptase polymerase chain reaction and Western blot were performed. With the use of immunofluorescence analysis, the investigated proteins were localized in the tissues. The expression levels of inflammatory mediators such as IL-1β, IL-6, IL-10, TGF, COX1, COX2, STAT3, and VEGF were evaluated by quantitative reverse transcriptase polymerase chain reaction, and their relationships were detected by the STRING approach.

RESULT(S)

The endometrium of women with type 3 leiomyomas exhibited differential expression of MMPs and TIMPs, particularly MMP2, MMP11, and MMP14, as well as different topographic distribution, suggesting that leiomyomas may influence the endometrial molecular profile. Significant decreases in IL-1β, IL-6, and IL-10 expression, along with increases in COX1 and COX2, as well as VEGF, were highlighted. The STRING approach suggests that this altered gene expression profile may affect the Th17 cell differentiation pathway.

CONCLUSION(S)

The differential expression and localization of MMPs and TIMPs observed in women with type 3 leiomyomas, along with the reported derangement in the expression of key molecules involved in the inflammatory pathway, may contribute to changes in endometrial receptivity in these patients.

Telomere Length and Male Fertility

Over the past decade, telomeres have attracted increasing attention due to the role they play in human fertility. However, conflicting results have been reported on the possible association between sperm telomere length (STL) and leukocyte telomere length (LTL) and the quality of the sperm parameters. The aim of this study was to run a comprehensive study to investigate the role of STL and LTL in male spermatogenesis and infertility. Moreover, the association between the sperm parameters and 11 candidate single nucleotide polymorphisms (SNPs), identified in the literature for their association with telomere length (TL), was investigated. We observed no associations between sperm parameters and STL nor LTL. For the individual SNPs, we observed five statistically significant associations with sperm parameters: considering a p < 0.05. Namely, ACYP2˗rs11125529 and decreased sperm motility (p = 0.03); PXK˗rs6772228 with a lower sperm count (p = 0.02); NAF1˗rs7675998 with increased probability of having abnormal acrosomes (p = 0.03) and abnormal flagellum (p = 0.04); ZNF208˗rs8105767 and reduction of sperms with normal heads (p = 0.009). This study suggests a moderate involvement of telomere length in male fertility; however, in our analyses four SNPs were weakly associated with sperm variables, suggesting the SNPs to be pleiotropic and involved in other regulatory mechanisms independent of telomere homeostasis, but involved in the spermatogenic process.

Sperm DNA Methylation at Metabolism-Related Genes in Vegan Subjects

Objective

To investigate if epigenome of sperm cells could be dynamically affected by nutrition.

Design and Methods

We assessed 40 healthy volunteers with different dietary habits and collected their demographic characteristics, as well as clinical and anthropometric parameters. We compared methylation profiles in sperm quantified by bisulfite pyrosequencing, at promoter-associated CpG sites of genes involved in metabolism including fat mass and obesity-associated (FTO) and melanocortin-4 receptor (MC4R) from six vegans and 34 omnivores. In addition, the FTO rs9939609 (T>A) was genotyped.

Results

Higher DNA methylation levels were detected in the sperm of vegan at FTO gene CpG1 (p=0.02), CpG2 (p=0.001), CpG3 (p=0.004), and CpG4 (p=0.003) sites and at MC4R-CpG2 site [p=0.016] as compared to sperm of omnivores. This association was not related to FTO genotype.

Conclusions

Although limited by the small number of investigated cases, our data provide insight into the role of diet on sperm DNA methylation in genes involved in metabolism.

Emerging role of embryo secretome in the paracrine communication at the implantation site: a proof of concept

OBJECTIVE

To assess the role of embryo secretome in modifying the molecular profile of glycodelin A (GdA) in endometrial organoids (ORG) mimicking the implantation window. To verify whether the use of embryo-conditioned culture medium at the time of the embryo transfer may increase in vitro fertilization outcome.

DESIGN

Molecular study with human endometrial ORG and embryo-conditioned culture medium. Retrospective study using prospectively recorded data.

SETTING

University hospital.

PATIENT(S)

For isolation and culture of endometrial glandular ORG, endometrial biopsy specimens from five white women of proven fertility undergoing laparoscopy for tubal sterilization. A total of 75 women undergoing intracytoplasmic sperm injection for tubal and/or male infertility factor.

INTERVENTIONS(S)

In vitro fertilization.

MAIN OUTCOME MEASURE(S)

Pinopodes presence in human endometrial ORG. Glycodelin A expression profile by means of two-dimensional electrophoresis. In vitro fertilization outcome.

RESULT(S)

This in vitro study demonstrated that the treatment of endometrial ORG with the secretome of medium conditioned by the growing embryo increased the GdA relative abundance and induced a different glycoform pattern. Biochemical and clinical pregnancy rate significantly increased when the spent medium was loaded during the transfer (17.5% vs. 36.6% and 16.5% vs. 35.1%, respectively).

CONCLUSION(S)

This study demonstrated that the secretome of implanting embryos is able to induce the expression as well as to determine the relative abundance and the glycosilation profile of endometrial GdA, a protein having a key role in the embryo-endometrial cross talk. Moreover, a significant increase in pregnancy rate was observed when the embryo transfer was performed by using the culture medium conditioned by the growing embryo.

Increased expression of neurogenic factors in uterine fibroids

STUDY QUESTION

Are selective markers for the neuronal differentiation such as microtubule-associated protein 2 (MAP-2) and synaptophysin (SYP) as well as the nerve growth factor (NGF) expressed by fibroids, myometrium and eutopic endometrium?

SUMMARY ANSWER

Neuronal markers NGF, MAP-2 and SYP are highly expressed in fibroids compared with matched myometrium, and this neurogenic pathway is upregulated by tumor necrosis factor (TNF) alpha in cultured smooth muscle cells (SMCs).

WHAT IS KNOWN ALREADY

Uterine fibroids or leiomyomas are the most common benign tumors, accounting for approximately one-third of hysterectomies. The present trend is to improve the medical treatment avoiding surgery, also for fertility sparing; hence, the pathogenic mechanisms are investigated, aiming to develop new therapeutic strategy.

STUDY DESIGN, SIZE, DURATION

This laboratory-based case-control study is focused on fibroids and myometrial specimens obtained between 2015 and 2017 from 15 women of reproductive age at the proliferative phase of the menstrual cycle. Leiomyomas, matched myometrium and endometrium from each woman were analyzed. Control endometrium was obtained from women undergoing surgery for ovarian cyst (n = 15).

PARTICIPANTS/MATERIALS, SETTING, METHODS

qRT-PCR, western blotting and immunostaining were applied to evaluate the expression of neurogenic markers; the effects of TNF on NGF, MAP-2 and SYP expression in cultured SMCs from leiomyomas and matched myometrium were analyzed.

MAIN RESULTS AND THE ROLE OF CHANCE

qRT-PCR analyses using tissues from clinical patients showed that the levels of NGF, MAP-2 and SYP mRNA were significantly higher in uterine leiomyomas compared with their matched myometrium (P < 0.05), whereas only NGF was significantly increased in eutopic endometrium compared with healthy endometrium. In primary SMCs, isolated from fibroids or from the adjacent myometrium, NGF, MAP-2 and SYP mRNA expression were significantly increased by TNF treatment (P < 0.05). Finally, human endometrial stromal cells prepared from the endometrium of patients affected by uterine fibroids display higher TNF expression (P < 0.001).

LIMITATIONS, REASONS FOR CAUTION

qRT-PCR analysis and immunofluorescence validation are robust methods demonstrating a clear upregulation of neurogenic factors in leiomyomas, even though additional studies are needed to establish a correlation between increased neuronal gene expression and degree of pain, as well as the involvement of inflammation mediators in the development of the neurogenic unhinge. Therefore, more in vivo studies are needed to confirm the results achieved from primary cultured SMCs.

WIDER IMPLICATIONS OF THE FINDINGS

The increased expression of neurogenic factors in uterine fibroids and endometrium may contribute to explain the painful stimuli. Accordingly, these neurogenic pathways may represent potential therapeutic avenues to treat the fibroid-related disorders.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by research grants from the University of Siena. The authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Characterization of the Age-Dependent Changes in Antioxidant Defenses and Protein's Sulfhydryl/Carbonyl Stress in Human Follicular Fluid

The oxidative stress, characterized by the imbalance between pro-oxidants and antioxidants molecules, seems to be involved in the pathogenesis of female subfertility. In particular, the presence of different markers of oxidative stress has been reported in human follicular fluid (FF) surrounding oocytes. Based on its distinctive composition and on the close proximity to the oocyte, FF creates a unique microenvironment having a direct impact on oocyte quality, implantation, and early embryo development. An imbalance in reactive oxygen species (ROS) production in ovarian follicular fluid may have a negative effect on these processes and, as a consequence, on female fertility. Therefore, the aim of this study was to evaluate the redox state of the FF through various methodological approaches. By means of 2D-electrophoresis we demonstrated that the main structural changes occurring in the proteins of the follicular fluid of normovulatory women were correlated to the age of the patients and to the antioxidant defenses present in the FF. Measurement of these parameters could have clinical relevance, since the assessment of the oxidative stress rate may be helpful in evaluating in vitro fertilization potential.

Relationship between the metabolic and lipid profile in follicular fluid of women undergoing in vitro fertilization

Among the follicular fluid (FF) components promoting the development of the oocyte are included glycoproteins, several fatty acids, and steroid hormones synthesized by the dominant follicle. For this, the analysis of the metabolites present in FF can determine the quality of the oocyte. FF composition is in part determined by local follicular metabolic processes and in part a plasma transudate. Since the causes of impaired fertility may be due to a metabolic imbalance, metabolomics is useful to identify low molecular weight metabolites. Oxidative stress is involved in human infertility and the use of metabolomics can be crucial to identify which other metabolites besides reactive oxygen species are involved in oxidative stress correlated to infertility. To obtain new information on the study of signaling molecules in FF, the knowledge of the lipid content will be important to improve information on the understanding of follicular development. The objective of this study is to identify (a) a metabolic profile and a lipid profile of FF in women undergoing in vitro fertilization and (b) to correlate the previous information obtained regarding adiponectin and oxidative stress with the metabolic and lipid profile obtained in the present study. As result, we found an increase in oxidative stress due to both an increase of androgens and an accumulation of lipids in the follicular environment and we suggest that this might be one of the causes of reduced fertility.

Metformin doses and body mass index: clinical outcomes in insulin resistant polycystic ovary syndrome women

OBJECTIVE

PCOS is the most common endocrinopathy among reproductive age women. Approximately 60% of PCOS women have insulin resistance. While the efficacy of metformin in reducing insulin resistance and decreasing androgen level has been widely validated, there is no agreement on the dose of metformin to be used.

PATIENTS AND METHODS

Prospective non-randomized cohort study of 108 insulin resistant, overweight and obese PCOS women, aged between 22 and 35 years. All patients received 1500 mg of metformin (500 mg x 3 times/day) for the first 6 months. At the end of this period, the patients' HOMA index was evaluated. In subjects, who did not demonstrate normalization of the HOMA index, the dose was increased to 2500 mg/day (500 mg at breakfast and 1000 mg at lunch and dinner) for additional 6 months. The hormonal blood profile, fasting insulin and fasting glucose levels, HOMA index, anthropometric assessment, pelvic ultrasound, FAI index and cholesterol were evaluated.

RESULTS

Overall results showed a good response to metformin therapy in insulin-resistant PCOS patients with BMI >25, while in patients with higher BMI (31.15 ± 0.40), no normalization of HOMA was found. At the higher dose of metformin, obese patients achieved a good response to therapy, with improvement in BMI, menstrual pattern, cholesterol levels and hyperandrogenism.

CONCLUSIONS

Our results demonstrate a correlation between the required dose of metformin, BMI and hyperandrogenism. The dose of metformin should be adjusted to patients' BMI in order to obtain significant results in terms of clinical, metabolic and hormonal responses.

Expression of Matrix Metalloproteinases and Their Inhibitors in Endometrium: High Levels in Endometriotic Lesions

Endometriosis is a condition defined as presence of endometrium outside of the uterine cavity. These endometrial cells are able to attach and invade the peritoneum or ovary, thus forming respectively the deep infiltrating endometriosis (DIE) and the ovarian endometrioma (OMA), the ectopic lesions feature of this pathology. Endometriotic cells display high invasiveness and share some features of malignancy with cancer cells. Indeed, the tissue remodeling underlining lesion formation is achieved by matrix metalloproteinases (MMPs) and their inhibitors. Therefore, these molecules are believed to play a key role in development and pathogenesis of endometriosis. This study investigated the molecular profile of metalloproteinases and their inhibitors in healthy (n = 15) and eutopic endometrium (n = 19) in OMA (n = 10) and DIE (n = 9); moreover, we firstly validated the most reliable housekeeping genes allowing accurate gene expression analysis in these tissues. Gene expression, Western blot, and immunofluorescence analysis of MMP2, MMP3, and MMP10 and their tissue inhibitors TIMP1 and TIMP2 demonstrated that these enzymes are finely tuned in these tissues. In OMA lesions, all the investigated MMPs and their inhibitors were significantly increased, while DIE expressed high levels of MMP3. Finally, in vitro TNFα treatment induced a significant upregulation of MMP3, MMP10, and TIMP2 in both healthy and eutopic endometrial stromal cells. This study, shedding light on MMP and TIMP expression in endometriosis, confirms that these molecules are altered both in eutopic endometrium and endometriotic lesions. Although further studies are needed, these data may help in understanding the molecular mechanisms involved in the extracellular matrix remodeling, a crucial process for the endometrial physiology.

Expression of Taste Receptor 2 Subtypes in Human Testis and Sperm

Taste receptors (TASRs) are expressed not only in the oral cavity but also throughout the body, thus suggesting that they may play different roles in organ systems beyond the tongue. Recent studies showed the expression of several TASRs in mammalian testis and sperm, indicating an involvement of these receptors in male gametogenesis and fertility. This notion is supported by an impaired reproductive phenotype of mouse carrying targeted deletion of taste receptor genes, as well as by a significant correlation between human semen parameters and specific polymorphisms of taste receptor genes. To better understand the biological and thus clinical significance of these receptors for human reproduction, we analyzed the expression of several members of the TAS2Rs family of bitter receptors in human testis and in ejaculated sperm before and after in vitro selection and capacitation. Our results provide evidence for the expression of TAS2R genes, with TAS2R14 being the most expressed bitter receptor subtype in both testis tissue and sperm cells, respectively. In addition, it was observed that in vitro capacitation significantly affects both the expression and the subcellular localization of these receptors in isolated spermatozoa. Interestingly, α-gustducin and α-transducin, two Gα subunits expressed in taste buds on the tongue, are also expressed in human spermatozoa; moreover, a subcellular redistribution of both G protein α-subunits to different sub-compartments of sperm was registered upon in vitro capacitation. Finally, we shed light on the possible downstream transduction pathway initiated upon taste receptor activation in the male reproductive system. Performing ultrasensitive droplets digital PCR assays to quantify RNA copy numbers of a distinct gene, we found a significant correlation between the expression of TAS2Rs and TRPM5 (r = 0.87), the cation channel involved in bitter but also sweet and umami taste transduction in taste buds on the tongue. Even if further studies are needed to clarify the precise functional role of taste receptors for successful reproduction, the presented findings significantly extend our knowledge of the biological role of TAS2Rs for human male fertility.

Proteostasis network alteration in lysosomal storage disorders: Insights from the mouse model of Krabbe disease

In Krabbe disease, a mutation in GALC gene causes widespread demyelination determining cell death by apoptosis, mainly in oligodendrocytes and Schwann cells. Less is known on the molecular mechanisms induced by this deficiency. Here, we report an impairment in protein synthesis and degradation and in proteasomal clearance with a potential accumulation of the misfolded proteins and induction of the endoplasmic reticulum stress in the brain of 6-day-old twitcher mice (TM) (model of Krabbe disease). In particular, an imbalance of the immunoproteasome function was highlighted, useful for shaping adaptive immune response by neurological cells. Moreover, our data show an involvement of cytoskeleton remodeling in Krabbe pathogenesis, with a lamin meshwork disaggregation in twitcher oligodendrocytes in 6-day-old TM. This study provides interesting protein targets and mechanistic insight on the early onset of Krabbe disease that may be promising options to be tested in combination with currently available therapies to rescue Krabbe phenotype.

Functional polymorphism within NUP210 encoding for nucleoporin GP210 is associated with the risk of endometriosis

OBJECTIVE

To investigate whether nucleoporin 210 (GP210, encoded by NUP210 gene) is involved in endometriosis.

DESIGN

Immunohistofluorescence analysis for assessing whether GP210 is expressed in endometrial tissues from patients and controls; genotyping and case-control study for assessing the association between rs354476 within NUP210 and risk of endometriosis; in vitro luciferase assay for assessing the functional activity of rs354476.

SETTING

University.

PATIENT(S)

Histologically diagnosed cases (n = 175) of endometriosis: minimal or mild (stage I-II) in 48 cases (28%), moderate (stage III) in 69 cases (39%), and severe (stage IV) in 58 cases (33%). Controls (n = 557) were female blood donors collected at Meyer Hospital of Florence.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

GP210 tissue expression; genotype distribution and risk of endometriosis; in vitro gene expression measurements.

RESULT(S)

GP210 had positive nuclear immunohistofluorescence staining in endometrial glandular epithelium. Carriers of the variant allele were associated with increased risks: C/T, odds ratio (OR) 1.83, 95% confidence interval (CI) 1.04-3.21; T/T, OR 2.55, 95% CI 1.36-4.80. In vitro, luciferase assay showed that rs354476 is a bona fide target for hsa-miR-125b-5p.

CONCLUSION(S)

Nucleoporin GP210 is involved in endometriosis. Rs354476 polymorphism affects the regulation of NUP210 gene expression by altering the binding with hsa-miR-125b-5p, a microRNA already known as playing an important role for endometriosis. This provides the rationale for the observed increased risk of endometriosis in carriers of the variant allele.

Taste Receptors: New Players in Sperm Biology

Taste receptors were first described as sensory receptors located on the tongue, where they are expressed in small clusters of specialized epithelial cells. However, more studies were published in recent years pointing to an expression of these proteins not only in the oral cavity but throughout the body and thus to a physiological role beyond the tongue. The recent observation that taste receptors and components of the coupled taste transduction cascade are also expressed during the different phases of spermatogenesis as well as in mature spermatozoa from mouse to humans and the overlap between the ligand spectrum of taste receptors with compounds in the male and female reproductive organs makes it reasonable to assume that sperm "taste" these different cues in their natural microenvironments. This assumption is assisted by the recent observations of a reproductive phenotype of different mouse lines carrying a targeted deletion of a taste receptor gene as well as the finding of a significant correlation between human male infertility and some polymorphisms in taste receptors genes. In this review, we depict recent findings on the role of taste receptors in male fertility, especially focusing on their possible involvement in mechanisms underlying spermatogenesis and post testicular sperm maturation. We also highlight the impact of genetic deletions of taste receptors, as well as their polymorphisms on male reproduction.

Matrix metalloproteinases and their inhibitors in human cumulus and granulosa cells as biomarkers for oocyte quality estimation

OBJECTIVE

To study the molecular profile of metalloproteinases and their tissue inhibitors in granulosa and cumulus cells in a subset of fertile and infertile women.

DESIGN

Molecular study with granulosa and cumulus cells.

SETTING

University hospital.

PATIENT(S)

Forty-four women undergoing assisted reproductive techniques for female infertility factor, with partners having a normal spermiogram and 15 normally fertile women with male partner affected by severe oligoasthenoteratozoospermia or nonobstructive azoospermia.

INTERVENTION(S)

In vitro fertilization.

MAIN OUTCOME MEASUREMENT(S)

We investigated gene expression level of metalloproteinases (MMP2, MMP9, MMP11) and their tissue inhibitors (TIMP1, TIMP2) by means of quantitative reverse-transcription polymerase chain reaction, protein quantification by means of Western blot, and localization by means of immunofluorescence.

RESULT(S)

We firstly validated HPRT1 as the most reliable housekeeping gene enabling correct gene expression analysis in both granulosa and cumulus cells. Gene expression, Western blot, and immunofluorescence analysis of MMP2, MMP9, and MMP11 and their tissue inhibitors TIMP1 and TIMP2 demonstrated that these enzymes are finely tuned in these cells. MMP9 is specifically expressed only in granulosa, whereas MMP2 is more expressed in cumulus and granulosa cells in cases of reduced ovarian response and decreased fertilization rate.

CONCLUSION(S)

This study sheds light on MMP and TIMP expression in granulosa and cumulus cells, and it may help in understanding the fine regulation of oocyte maturation inside the follicle. Although further studies are needed to fully understand the molecular mechanisms involved in these processes, our findings may be useful in the identification of biomarkers of oocyte maturation, competence acquiring, and fertilization.

Impact of asymptomatic genital tract infections on in vitro Fertilization (IVF) outcome

Background

Infertility is estimated to affect approximately 9–30% of reproductive-aged couples. Several conditions involving one or both partners may contribute to infertility. The aim of this study is to evaluate the role of asymptomatic genital tract infections in the outcome of In Vitro Fertilization (IVF) in couples with infertility.

Methods

A total of 285 infertile couples were enrolled in the study. Vaginal/endocervical swabs and semen samples were collected and subjected to microbiological analysis. Spermiograms were carried out on semen specimens, and lactobacilli were quantified in vaginal swabs. Data were associated with IVF results and analysed by using non parametric tests and multivariate analysis.

Results

Microbiological analysis showed that 46.3% of couples presented with an asymptomatic genital tract infection. Spermiogram results showed a significantly diminished motility of sperm cells in samples positive to microbiological testing compared to negative specimens. Enterococcus faecalis was the most prevalent species (11.6%) in positive semen samples and was found to negatively affect both sperm morphology (p = 0.026) and motility (p = 0.003). Analysis of genital swabs from females showed that the presence of E. faecalis (p<0.0001), Escherichia coli (p = 0.0123), Streptococcus agalactiae (p<0.0001), and Gardnerella vaginalis (p = 0.0003) was significantly associated to reduced levels of vaginal lactobacilli. Association of microbiological data with IVF outcome showed that 85.7% of IVF+ couples was microbiologically negative, while IVF was successful in just 7.5% of couples infected with E. faecalis and/or U. urealyticum and/or M. hominis (p = 0.02).

Conclusions

The results show the negative impact of E. faecalis on sperm quality and the association of definite bacterial pathogens with reduced levels of vaginal lactobacilli. The presence of E. faecalis and/or U. urealyticum and/or M. hominis in genital samples of infertile couples is predictive for a negative outcome of IVF.

Taste receptor polymorphisms and male infertility

STUDY QUESTION

Are polymorphisms of taste receptor genes associated with male infertility?

SUMMARY ANSWER

This study has showed the associations between three single nucleotide polymorphisms (SNPs) in taste receptors genes (TASR) and male infertility.

WHAT IS KNOWN ALREADY

Recent studies showed the expression of taste receptors in the testis and in spermatozoa, suggesting their possible role in infertility. The vast genetic variability in taste genes results in a large degree of diversity in various human phenotypes.

STUDY DESIGN, SIZE, DURATION

In this study, we genotyped 19 SNPs in 12 taste related genes in a total of 494 Caucasian male patients undergoing semen evaluation at the Centre of Couple Sterility of the Siena University Hospital. Consecutive patients were enrolled during infertility investigations from October 2014 to February 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Median age of the patients was 36 years (18-58) and 141 were smokers. Genotyping was performed using the allele-specific PCR. The statistical analysis was carried out using generalized linear model (GLM) to explore the association between age, smoking, the genetic polymorphisms and sperm parameters.

MAIN RESULTS AND THE ROLE OF CHANCE

We observed that the homozygous carriers of the (G) allele of the TAS2R14-rs3741843 polymorphism showed a decreased sperm progressive motility compared to heterozygotes and (A) homozygotes (P = 0.003). Moreover, the homozygous carriers of the (T) allele of the TAS2R3-rs11763979 SNP showed fewer normal acrosome compared with the heterozygous and the homozygous carriers of the (G) allele (P = 0.002). Multiple comparisons correction was applied and the Bonferroni-corrected critical P-value was = 0.003.

LIMITATIONS, REASONS FOR CAUTION

The analysis is restricted to SNPs within genes and to men of Caucasian ancestry.

WIDER IMPLICATIONS OF THE FINDINGS

In silico analyses strongly point towards a functional effect of the two SNPs: TAS2R14-rs3741843 regulates TAS2R43 expression, a gene that is involved in cilia motility and therefore could influences sperm mobility; the (T) allele of TAS2R3-rs11763979 increases the expression of the WEE2 antisense RNA one gene (WEE2-AS1). According to Genotype-Tissue Expression (GTEx) project the WEE2 gene is expressed in the testes where presumably it has the role of down regulating meiotic cell division. It is plausible to hypothesize that the WEE2-AS1 increased expression may down regulate WEE2 which in turn can alter the natural timing of sperm maturation increasing the number of abnormal sperm cells.

STUDY FUNDING/COMPETING INTEREST(S)

None.

SA1/SA2 cohesion proteins and SIRT1-NAD+ deacetylase modulate telomere homeostasis in cumulus cells and are eligible biomarkers of ovarian aging

STUDY QUESTION

Are cohesins SA1/SA2 and the NAD-dependent deacetylase SIRT1 involved in telomere homeostasis of cumulus cells and thus eligible as biomarkers of follicular physiology and ovarian aging?

SUMMARY ANSWER

SA1/SA2 cohesins and SIRT1 are associated with telomere length in cumulus cells and may be eligible biomarkers of follicular physiology and ovarian aging.

WHAT IS KNOWN ALREADY

In somatic cells, cohesins SA1/SA2 mediate sister chromatid cohesion at the telomere termini (for SA1) and along chromatid arms (for SA2). The NAD+-dependent protein deacetylase Sirtuin 1 (SIRT1), which preserves DNA integrity from oxidative stress, may also modulate genome stability and telomere length.

STUDY DESIGN, SIZE, DURATION

Collectively 280 cumulus/oocyte complex samples were recovered from a total of 50 women undergoing in vitro fertilization.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Cumulus cells were separated from the oocyte-cumulus complex. DNA and total mRNA were extracted from cumulus cells and assayed for telomere length and for SA1, SA2 and SIRT1 gene expression profiling. Telomere length was determined by quantitave PCR and analyzed relative to the single copy of the housekeeping gene (albumin) to generate a T/S ratio (Telomere/single copy gene). Gene expression levels of SA1, SA2 and SIRT1 mRNA were assayed by quantitative RT-PCR and confirmed by western blotting and immunofluorescent studies (SIRT1). SA1/SA2 and SIRT1 gene expression levels and telomere length analysis of patients/samples were ranked in relation to their clinical setting parameters (BMI, age) and to the number of oocyte retrieved.

MAIN RESULTS AND THE ROLE OF CHANCE

SA1 and SA2 transcripts were both detected in all cumulus cells analyzed and the relative amount showed a clear decreasing trend according to the age of patients. A significant increase in SA1 and SA2 was disclosed in high responder women (>6 oocytes retrieved) compared to poor responders (<4 oocytes) (P < 0.05). Furthermore, statistically significant positive correlations were also recorded between the transcripts levels of the two cohesin molecules (r = 0.89; P < 0.05) and, to a lesser extent, between telomere length and SA1 (r = 0.42; P < 0.001) and SA2 (r = 0.36; P < 0.001) mRNA levels. SIRT1 expression was also significantly increased in high responders (>6 oocytes) compared to poor responders. Significant correlations were found between SIRT1 and SA1 (r = 0.69; P < 0.001), between SIRT1 and SA2 (r = 0.78; P < 0.001), and between SIRT1 and telomere length (r = 0.36; P < 0.001). However, in the older patient group (>38 years), SIRT1 mRNA levels were twice as high as the levels recorded in the younger patient cohort (<34 years). Western blot analysis and immunofluorescent studies confirmed the increments in SIRT1 protein levels in patients over 38 years old.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

Cumulus/oocyte complexes were retrieved by patients undergoing ovarian stimulation protocol for IVF. We cannot exclude the possibility that different stimulation protocols affect the correlations highlighted in this study. Future investigations should shed light on cumulus cells molecular profile according to different stimulation protocols.

WIDER IMPLICATIONS OF THE FINDINGS

The overall results of our study point to the involvement of cohesins SA1/SA2 and SIRT1 deacetylase in telomere homeostasis in cumulus cells and highlight their possible eligibility as biomarkers of follicular physiology and ovarian aging.

STUDY FUNDING/COMPETING INTEREST(S)

Merck Serono S.P.A Italy sponsored the study with financial support. There are no competing interests to declare.

Suppression of galactocerebrosidase premature termination codon and rescue of galactocerebrosidase activity in twitcher cells

Krabbe's disease (KD) is a degenerative lysosomal storage disease resulting from deficiency of β-galactocerebrosidase activity. Over 100 mutations are known to cause the disease, and these usually occur in compound heterozygote patterns. In affected patients, nonsense mutations leading to a nonfunctional enzyme are often found associated with other mutations. The twitcher mouse is a naturally occurring model of KD, containing in β-galactocerebrosidase a premature stop codon, W339X. Recent studies have shown that selected compounds may induce the ribosomal bypass of premature stop codons without affecting the normal termination codons. The rescue of β-galactocerebrosidase activity induced by treatment with premature termination codon (PTC) 124, a well-characterized compound known to induce ribosomal read-through, was investigated on oligodendrocytes prepared from twitcher mice and on human fibroblasts from patients bearing nonsense mutations. The effectiveness of the nonsense-mediated mRNA decay (NMD) inhibitor 1 (NMDI1), a newly identified inhibitor of NMD, was also tested. Incubation of these cell lines with PTC124 and NMDI1 increased the levels of mRNA and rescued galactocerebrosidase enzymatic activity in a dose-dependent manner. The low but sustained expression of β-galactocerebrosidase in oligodendrocytes was sufficient to improve the morphology of the differentiated cells. Our in vitro approach provides the basis for further investigation of ribosomal read-through as an alternative therapeutic strategy to ameliorate the quality of life in selected KD patients. © 2016 Wiley Periodicals, Inc.

Impaired spermatogenesis in the twitcher mouse: A morphological evaluation from the seminiferous tubules to epididymal transit

Spermatogenesis is a complex process of proliferation and differentiation during male germ cell development whereby undifferentiated spermatogonial germ cells evolve into maturing spermatozoa. In this developmental process the interactions between different cell types are finely regulated, hence any disruption in these relationships leads to male infertility. The twitcher mouse, the murine model of Krabbe disease, is characterized by deficiency of galactosylceramidase, an enzyme also involved in the metabolism of the galactosyl-alkyl-acyl-glycerol, the precursor of sulfogalactosyl-alkyl-acyl-glycerol, the most abundant glycolipid in spermatozoa. Twitcher mice are sterile due to alterations of spermatogenesis resulting in the production of spermatozoa with abnormally swollen acrosomes and bent flagella, mainly at the midpiece-principal piece junction. The current study employs light, fluorescence, and electron microscopy to examine the defective spermiogenesis leading to the morphological abnormalities of mature sperm. This study reveals that alterations in germ cell development can be initially detected at the stage VIII and IX of spermatogenesis. The disrupted spermatogenetic process leads to a reduced number of elongating spermatids and spermatozoa in these mutant animals. Electron microscopy analysis demonstrates major acrosomal and chromatin condensation defects in the mutants. In addition, in twitcher mice, the epididymal architecture is impaired, with stereocilia of caput and corpus broken, detached and completely spread out into the lumen. These findings indicate that seminolipid expression is crucial for proper development of spermatocytes and spermatids and for their normal differentiation into mature spermatozoa.

ABBREVIATIONS

GALC: galactosylceramidase; GalAAG: galactosyl-alkyl-acyl-glycerol; SGalAAG: sulfogalactosylalkylacylglycerol; PND: postnatal day; PAS: periodic acid-Schiff stain; TEM: transmission electron microscopy; SEM: scanning electron microscopy; PFA: paraformaldheyde.

Single nucleotide polymorphisms of USP26 in azoospermic men

Some studies have focused on the association between male infertility and single nucleotide polymorphisms (SNPs) in the ubiquitin-specific protease 26 (USP26) gene, but the results are controversial. In this case-control study including both normozoospermic men and patients with nonobstructive azoospermia, we analyzed both the entire coding region and 5' and 3' untranslated regions of USP26 in order to identify genetic variants in this gene to investigate the role of USP26 on spermatogenesis. We reported variations in the USP26 gene sequence in 82% of azoospermic and in 50% normospermic men. The synonymous variation c.576G>A has a frequency significantly different in the azoospermic (60.2%) and normozoospermic (23.6%) groups, while the frequencies in the two groups of both c.1090C>T and c.1737G>A missense mutations did not reach statistical significance. A cluster mutation (c.371insACA, c.494T>C) was detected in 2 normozoospermic men (2.7%). In the 5'UTR we identified the -33C>T variation both in azoospermic (3.8%) and in normozoospermic (2.7%) men. In a normozoospermic man we detected the nonsense mutation c.882C>A, never reported to date. According to our results, we suggest that only the variation c.576G>A has a frequency significantly different in azoospermic compared to normozoospermic men. Moreover, the identification in a normozoospermic man of a nonsense mutation (c.882C>A) which causes the production of a truncated protein, suggests a marginal role of USP26 in male spermatogenesis. Additional studies may be useful as we cannot exclude that the other SNPs may represent risk factors for male fertility acting by an oligogenic/polygenic mechanism.

Antioxidants reduce oxidative stress in follicular fluid of aged women undergoing IVF

BACKGROUND

The status characterized by the imbalance between pro-oxidants and antioxidants molecules, defined as oxidative stress, has been suggested to be involved in the pathogenesis of subfertility in females. This study aims to evaluate the impact of a complete micronutrients supplementation on oxidative stress levels in follicular microenvironment as well as on in vitro fertilization (IVF) outcome.

METHODS

This preliminary study was conducted between January 2014 and July 2015 at the Siena University Hospital Infertility Clinic. Serum and follicular fluid were collected from infertile women aged > 39 years who underwent two in vitro fertilization cycles: in the first cycle they were treated with GnRH-antagonist protocol and gonadotropins for controlled ovarian hyperstimulation, whereas in the second cycle ovarian stimulation protocol was associated to micronutrients supplementation, starting three months earlier. Protein oxidation levels and total antioxidant capacity in serum and in follicular fluid were evaluated in IVF cycles with or without micronutrients supplementation. Differences in IVF outcome parameters were statistically evaluated.

RESULTS

Two-dimensional electrophoresis analyses demonstrated that when patients assumed micronutrients before IVF cycles, follicular fluid and serum proteins were protected from oxidative damage. Comparable results were obtained when total antioxidant capacity was measured. Moreover, the mean number of good quality oocytes retrieved when patients received micronutrients supplementation was significantly increased.

CONCLUSION

The additional treatment with micronutrients, starting three months before IVF cycles, protects the follicular microenvironment from oxidative stress, thus increasing the number of good quality oocytes recovered at the pick up.

Urocortin and corticotrophin-releasing hormone receptor type 2 mRNA are highly expressed in deep infiltrating endometriotic lesions

Ovarian endometrioma (OMA) and deep infiltrating endometriosis (DIE) are the most severe forms of endometriosis, but different pathogenetic mechanisms and clinical symptoms distinguish these two forms. Corticotrophin-releasing hormone (CRH) and urocortin (Ucn) are endometrial neuropeptides involved in tissue differentiation and inflammation. The expression of CRH, Ucn, Ucn2, CRH-receptors (type-1 and type-2) and inflammatory enzymes phospholipase-A2 group IIA (PLA2G2A) and cycloxygenase-2 (COX2) were evaluated in OMA (n = 22) and DIE (n = 26). The effect of CRH or Ucn on COX2 mRNA expression was evaluated in cultured human endometrial stromal cells. In DIE lesions, CRH, Ucn and CRH-R2 mRNA levels were significantly higher than in OMA (P < 0.01, P < 0.001 and P < 0.05, respectively); DIE lesions showed a higher expression of COX2 (P < 0.01) and PLA2G2A (P < 0.05) mRNA than OMA, which was positively correlated with CRH-R2 mRNA expression (P < 0.05). Intense immunostaining for CRH and Ucn was shown in DIE. Treatment of cultured endometrial stromal cells with Ucn significantly increased COX2 mRNA expression (P < 0.01); this effect was reversed by the CRH-R2 antagonist astressin-2B. In DIE, DIE lesions highly express neuropeptide and enzyme mRNAs, supporting a strong activation of inflammatory pathways.

Intravenous injection of AAVrh10-GALC after the neonatal period in twitcher mice results in significant expression in the central and peripheral nervous systems and improvement of clinical features

Globoid cell leukodystrophy (GLD) or Krabbe disease is an autosomal recessive disorder resulting from the defective lysosomal enzyme galactocerebrosidase (GALC). The lack of GALC enzyme leads to severe neurological symptoms. While most human patients are infants who do not survive beyond 2 years of age, older patients are also diagnosed. In addition to human patients, several naturally occurring animal models, including dog, mouse, and monkey, have also been identified. The mouse model of Krabbe disease, twitcher (twi) mouse has been used for many treatment trials including gene therapy. Using the combination of intracerebroventricular, intracerebellar, and intravenous (iv) injection of the adeno-associated virus serotype rh10 (AAVrh10) expressing mouse GALC in neonate twi mice we previously have demonstrated a significantly extended normal life and exhibition of normal behavior in treated mice. In spite of the prolonged healthy life of these treated mice and improved myelination, it is unlikely that using multiple injection sites for viral administration will be approved for treatment of human patients. In this study, we have explored the outcome of the single iv injection of viral vector at post-natal day 10 (PND10). This has resulted in increased GALC activity in the central nervous system (CNS) and high GALC activity in the peripheral nervous system (PNS). As we have shown previously, an iv injection of AAVrh10 at PND2 results in a small extension of life beyond the typical lifespan of the untreated twi mice (~40 days). In this study, we report that mice receiving a single iv injection at PND10 had no tremor and continued to gain weight until a few weeks before they died. On average, they lived 20-25 days longer than untreated mice. We anticipate that this strategy in combination with other therapeutic options may be beneficial and applicable to treatment of human patients.

Morphological and molecular characterisation of Twitcher mouse spermatogenesis: an update

Spermatogenesis is a complex developmental program in which interactions between different cell types are finely regulated. Mouse models in which any of the sperm maturation steps are perturbed provide major insights into the molecular control of spermatogenesis. The Twitcher mouse is a model of Krabbe disease, characterised by the deficiency of galactosylceramidase, the enzyme that hydrolyses galactosylceramide and galactosylsphingosine. Galactosyl-alkyl-acyl-glycerol, a precursor of seminolipid, the most abundant glycolipid in spermatozoa, is also a substrate for galactosylceramidase. Altered sphingolipid metabolism has been suggested to be the cause of the morphological abnormalities reported previously in the spermatogenesis of Twitcher. However, given the frequency of infertility associated with neurological impairment, we hypothesised that an unbalanced hormonal profile could contribute to male infertility in this mutant. In order to clarify this issue, we investigated potential variations in the expression of hormones and hormone receptors involved in the regulation of spermatogenesis. Our data show that, in the brain of Twitcher mouse, gonadotrophin-releasing hormone (GnRH), LH and FSH gene expression is decreased, whereas expression of androgen receptor (AR) and inhibin ?A (INH?A) is increased. The changes in gene expression for the LH and FSH receptors and AR in the testes support the hypothesis that altered sphingolipid metabolism is not the only cause of Twitcher infertility.

Protein modification as oxidative stress marker in follicular fluid from women with polycystic ovary syndrome: the effect of inositol and metformin

PURPOSE

The purpose of this study was to evaluate the oxidative stress status (OS) of follicular fluid (FF) and the oocyte quality in women with polycystic ovary syndrome (PCOS) undergoing different ovarian stimulation protocols.

METHODS

FF samples were collected after gonadotropin administration in association or not with metformin or D-chiro-inositol (DCI). OS status was then evaluated by checking the follicular fluid protein oxidation profile after specific labeling of aminoacidic free-SH groups, and two-dimensional electrophoresis followed by qualitative and semiquantitative analysis. Oocyte quality was assessed by international morphological criteria.

RESULTS

Our data indicated that both treatments, even if to different extent, recovered a significantly high level of free-SH groups in FF proteins of PCOS women clearly indicating a decrease of OS level with respect to that found in FF samples from gonadotropins alone treated women. A higher number of good quality MII oocytes was also observed in DCI (P < 0.05) or metformin (P < 0.05) study groups in comparison to untreated control group.

CONCLUSION

A natural supplement and a drug both showed a statistically significant positive effect on follicular milieu by decreasing the oxidative damage on FF proteins, as well as in recovering good quality oocytes.

Pharmacological chaperones increase residual β-galactocerebrosidase activity in fibroblasts from Krabbe patients

Krabbe disease or globoid cell leukodystrophy is a degenerative, lysosomal storage disease resulting from the deficiency of β-galactocerebrosidase activity. This enzyme catalyzes the lysosomal hydrolysis of galactocerebroside and psychosine. Krabbe disease is inherited as an autosomal recessive trait, and many of the 70 disease-causing mutations identified in the GALC gene are associated with protein misfolding. Recent studies have shown that enzyme inhibitors can sometimes translocate misfolded polypeptides to their appropriate target organelle bypassing the normal cellular quality control machinery and resulting in enhanced activity. In search for pharmacological chaperones that could rescue the β-galactocerebrosidase activity, we investigated the effect of α-Lobeline or 3',4',7-trihydroxyisoflavone on several patient-derived fibroblast cell lines carrying missense mutations, rather than on transduced cell lines. Incubation of these cell lines with α-lobeline or 3',4',7-trihydroxyisoflavone leads to an increase of β-galacocerebrosidase activity in p.G553R + p.G553R, in p.E130K + p.N295T and in p.G57S + p.G57S mutant forms over the critical threshold. The low but sustained expression of β-galactocerebrosidase induced by these compounds is a promising result; in fact, it is known that residual enzyme activity of only 15-20% is sufficient for clinical efficacy. The molecular interaction of the two chaperones with β-galactocerebrosidase is also supported by in silico analysis. Collectively, our combined in silico-in vitro approach indicate α-lobeline and 3',4',7-trihydroxyisoflavone as two potential pharmacological chaperones for the treatment or improvement of quality of life in selected Krabbe disease patients.

FOXL2 in human endometrium: hyperexpressed in endometriosis

The present study investigated expression and protein localization of FOXL2 messenger RNA (mRNA) in endometrium of healthy women and in patients with endometriosis during endometrial cycle. In endometriotic lesions, FOXL2 mRNA and protein were evaluated and a possible correlation with activin A mRNA expression changes was also studied. Endometrium was collected from healthy women (n = 52) and from women with endometriosis (n = 31) by hysteroscopy; endometriotic tissues were collected by laparoscopy (n = 38). FOXL2 gene expression analysis in endometrium of healthy women showed a significant expression and no significant changes in mRNA levels between proliferative and secretory phases; a similar pattern was observed in endometrium of patients with endometriosis. Immunohistochemical evaluation showed that FOXL2 protein localized in stromal and glandular cells and colocalized with SUMO-1. FOXL2 mRNA expression was 3-fold higher in endometriosis than in healthy endometrium (P < .01) and a positive correlation between FOXL2 and activin A mRNA was found (P < .05) in endometriosis. In conclusion, FOXL2 mRNA expression and its protein localization do not change during endometrial cycle in eutopic endometrium from healthy individuals or patients with endometriosis; the hyperexpression of FOXL2 in endometriotic lesions suggests an involvement of this transcriptional regulator, probably associated with activin A expression and related to the pathogenesis of endometriosis.

New players in the infertility of a mouse model of lysosomal storage disease: the hypothalamus-pituitary-gonadal axis

Mammalian spermatogenesis is a complex hormone-dependent developmental program where interactions between different cell types are finely regulated. Mouse models in which any of the sperm maturation steps are perturbed provide major insights into the molecular control of spermatogenesis. The Twitcher mouse is a model for the Krabbe disease, characterized by the deficiency of galactosylceramidase (GALC), a lysosomal enzyme that hydrolyzes the terminal galactose from galactosylceramide, a typical component of the myelin membrane. In addition, GALC catalyzes the hydrolysis of the terminal galactose from galactosyl-alkyl-acyl-glycerol, precursor of seminolipids, specifically expressed on the membrane of germ cells. Previous data reported by our group demonstrated that glycolipids play an important role in sperm maturation and differentiation. Moreover, we hypothesized that the severe impairment of the central nervous system that affects the Twitcher mouse could interfere with the hypothalamus-pituitary-gonadal axis function, contributing to infertility. To highlight this hypothesis we have determined, at molecular level, the potential variation in expression pattern of brain hormones involved in spermatogenesis regulation.

HLA-DQ typing in the diagnostic algorithm of celiac disease

OBJECTIVE

celiac disease (CD) is an immune-mediated chronic inflammatory disease associated with HLA-DQ2 and DQ8 molecules. We evaluated the role of HLA in the CD diagnostic algorithm in order to contribute to the development of practical indications for the use of HLA typing.

MATERIAL AND METHODS

we selected 317 subjects typed for DR-DQ genes. CD was present in 123 patients, and 89 were included in the study; a control sample of 70 healthy individuals was recruited.

RESULTS

64% of patients with CD carried DQ2 heterodimer (α5β2), 13.5% carried DQ8 heterodimer without DQ2, 21.4% only showed β2 chain and 1.1% were positive for DQ2 α5 chain. The only presence of α5 chain did not predispose to CD, while DQB1*02 allele resulted more frequent than in other reports, pointing out the intrinsic correlation between β2 chain and CD. In the case-control study we observed a progression of increased risk, ranging from 1:7 for HLA-DQ2 homozygous to 1:85 for DQ8 heterozygous subjects. Overall, 8,6% of first degree family members were affected, exclusively in presence of HLA-DQ2, -DQ8 or DQB1*02, and CD was significantly more frequent among siblings than parents. Finally, considering the different patterns of clinical presentation among the HLA-DQ risk classes identified we found no relationship between CD clinical presentation and HLA-DQ risk categories.

CONCLUSIONS

our results strengthen the evidence that HLA-DQ status strongly influences the development of CD and demonstrate that knowledge of a patient's HLA-DQ genotype allows to establish clinically relevant genetic risk profiles.