scholarly journals SLO3 auxiliary subunit LRRC52 controls gating of sperm KSPER currents and is critical for normal fertility

2015 ◽  
Vol 112 (8) ◽  
pp. 2599-2604 ◽  
Author(s):  
Xu-Hui Zeng ◽  
Chengtao Yang ◽  
Xiao-Ming Xia ◽  
Min Liu ◽  
Christopher J. Lingle
Keyword(s):  
Reproductive Tract ◽  
Mammalian Species ◽  
Critical Role ◽  
Membrane Conductance ◽  
Female Reproductive Tract ◽  
Vitro Fertilization ◽  
Mammalian Sperm ◽  
Auxiliary Subunit ◽  
Common Facet

Following entry into the female reproductive tract, mammalian sperm undergo a maturation process termed capacitation that results in competence to fertilize ova. Associated with capacitation is an increase in membrane conductance to both Ca2+ and K+, leading to an elevation in cytosolic Ca2+ critical for activation of hyperactivated swimming motility. In mice, the Ca2+ conductance (alkalization-activated Ca2+-permeable sperm channel, CATSPER) arises from an ensemble of CATSPER subunits, whereas the K+ conductance (sperm pH-regulated K+ current, KSPER) arises from a pore-forming ion channel subunit encoded by the slo3 gene (SLO3) subunit. In the mouse, both CATSPER and KSPER are activated by cytosolic alkalization and a concerted activation of CATSPER and KSPER is likely a common facet of capacitation-associated increases in Ca2+ and K+ conductance among various mammalian species. The properties of heterologously expressed mouse SLO3 channels differ from native mouse KSPER current. Recently, a potential KSPER auxiliary subunit, leucine-rich-repeat-containing protein 52 (LRRC52), was identified in mouse sperm and shown to shift gating of SLO3 to be more equivalent to native KSPER. Here, we show that genetic KO of LRRC52 results in mice with severely impaired fertility. Activation of KSPER current in sperm lacking LRRC52 requires more positive voltages and higher pH than for WT KSPER. These results establish a critical role of LRRC52 in KSPER channels and demonstrate that loss of a non-pore-forming auxiliary subunit results in severe fertility impairment. Furthermore, through analysis of several genotypes that influence KSPER current properties we show that in vitro fertilization competence correlates with the net KSPER conductance available for activation under physiological conditions.

scholarly journals Integration of Sperm Motility and Chemotaxis Screening with a Microchannel-Based Device

2010 ◽  
Vol 56 (8) ◽  
pp. 1270-1278 ◽  
Author(s):  
Lan Xie ◽  
Rui Ma ◽  
Chao Han ◽  
Kai Su ◽  
Qiufang Zhang ◽  
...  
Keyword(s):  
Sperm Motility ◽  
Reproductive Tract ◽  
Cumulus Cells ◽  
Female Reproductive Tract ◽  
Straight Channel ◽  
Vitro Fertilization ◽  
Mammalian Sperm ◽  
Reaction Capability ◽  
Mammalian Female

BACKGROUND Sperm screening is an essential step in in vitro fertilization (IVF) procedures. The swim-up method, an assay for sperm motility, is used clinically to select the ideal sperm for subsequent manipulation. However, additional parameters, including acrosome reaction capability, chemotaxis, and thermotaxis, are also important indicators of mammalian sperm health. To monitor both sperm motility and chemotaxis simultaneously during sperm screening, we designed and constructed a microdevice comprising a straight channel connected with a bibranch channel that mimics the mammalian female reproductive tract. METHODS The width and length of the straight channel were optimized to select the motile sperms. We selectively cultured cumulus cells in the bibranch channel to generate a chemoattractant-forming chemical gradient. Sperm chemotaxis was represented by the ratio of the sperm swimming toward different branches. RESULTS The percentage of motile sperms improved from 58.5% (3.8%) to 82.6% (2.9%) by a straight channel 7 mm in length and 1 mm in width. About 10% of sperms were found to be chemotactically responsive in our experiment, which is consistent with previous studies. CONCLUSIONS For the first time, we achieved the combined evaluation of both sperm motility and chemotaxis. The motile and chemotactically responsive sperms can easily be enriched on a lab-on-a-chip device to improve IVF outcome.

scholarly journals CatSperζ regulates the structural continuity of sperm Ca2+ signaling domains and is required for normal fertility

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Jean-Ju Chung ◽  
Kiyoshi Miki ◽  
Doory Kim ◽  
Sang-Hee Shim ◽  
Huanan F Shi ◽  
...  
Keyword(s):  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Targeted Disruption ◽  
Vitro Fertilization ◽  
Male Subfertility ◽  
Epididymal Spermatozoa ◽  
Mammalian Female ◽  
Signaling Domains

We report that the Gm7068 (CatSpere) and Tex40 (CatSperz) genes encode novel subunits of a 9-subunit CatSper ion channel complex. Targeted disruption of CatSperz reduces CatSper current and sperm rheotactic efficiency in mice, resulting in severe male subfertility. Normally distributed in linear quadrilateral nanodomains along the flagellum, the complex lacking CatSperζ is disrupted at ~0.8 μm intervals along the flagellum. This disruption renders the proximal flagellum inflexible and alters the 3D flagellar envelope, thus preventing sperm from reorienting against fluid flow in vitro and efficiently migrating in vivo. Ejaculated CatSperz-null sperm cells retrieved from the mated female uterus partially rescue in vitro fertilization (IVF) that failed with epididymal spermatozoa alone. Human CatSperε is quadrilaterally arranged along the flagella, similar to the CatSper complex in mouse sperm. We speculate that the newly identified CatSperζ subunit is a late evolutionary adaptation to maximize fertilization inside the mammalian female reproductive tract.

Capacitation mechanisms, and the role of capacitation as seen in eutherian mammals

1996 ◽  
Vol 8 (4) ◽  
pp. 581 ◽  
Author(s):  
RA Harrison
Keyword(s):  
Cell Death ◽  
Reproductive Tract ◽  
Physiological State ◽  
Hormonal Control ◽  
Female Reproductive Tract ◽  
Functional Heterogeneity ◽  
Vitro Fertilization ◽  
Range Of Functions

Capacitation, the process whereby spermatozoa are rendered capable of interacting with and fertilizing the egg, was discovered more than 40 years ago. However, our understanding of it is still far from satisfactory. Several factors conspire to obfuscate studies of capacitation mechanisms: the inherent functional heterogeneity of sperm populations, the range of functions used as parameters of capacitation (whence the endpoint of the process has become conceptually uncertain), and the several profound differences between model in vitro fertilization (IVF) systems and the situation in vivo in the female reproductive tract. Recent investigations in the author's laboratory have shown that bicarbonate/CO2, an essential component for successful IVF, causes rapid changes in lipid architecture of the sperm plasma membrane and slower changes in surface coating. These changes are accompanied by membrane destabilization and cell death. Evidence suggests that bicarbonate's actions are mediated through cyclic nucleotide signalling. Of particular note is the heterogeneity in rate of response to bicarbonate shown by individual cells in the sperm populations. Taken together with other observations, the findings suggest that capacitation is a series of positive destabilizing events that eventually lead to cell death. The 'capacitated' state would then be a window of destabilization within which spermatozoa can undergo a zona-induced acrosome reaction and display hyperactivated motility. Further along the destabilization pathway, spontaneous acrosome reactions would occur before total membrane degeneration. In vivo, capacitation would be a conflict between destabilization and sperm survival. Concentrations of bicarbonate are maintained low in the cauda epididymidis, where sperm survive for long periods, and one may speculate that hormonal control of local bicarbonate/CO2 in oviducal 'storage' sites in the female tract could allow 'safe' sequestering of live spermatozoa until around the time of ovulation; the environment may then change to produce a 'capacitating' effect, whence, due to the inherent functional heterogeneity of the sequestered population, small numbers of capacitated spermatozoa are released sequentially. In this way, a succession of spermatozoa in the correct physiological state may be provided for the freshly ovulated egg.

P–196 Bacterial influence on oocyte quality - the secret of a successful fertilization

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
M Schenk ◽  
E Voroshilina ◽  
M Boldyreva ◽  
M Koranda ◽  
N Reinschissler ◽  
...  
Keyword(s):  
Follicular Fluid ◽  
Genital Tract ◽  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Lactobacillus Species ◽  
Bacterial Composition ◽  
Vitro Fertilization ◽  
Dna Technology ◽  
Follicular Fluids

Abstract Study question Is there a difference in bacterial composition of follicular fluid between oocytes developing a good quality blastocyst and oocytes that fail fertilization? Summary answer Follicular fluids of oocytes failing fertilization show a different bacterial profile compared to follicular fluids of oocytes that were successfully fertilized. What is known already The presence of pathogens in the female reproductive tract has been intensively investigated. Lactobacillus species are mainly associated with a healthy genital tract and good prognosis for a successful pregnancy. Studies of the bacterial composition of follicular fluids have been mainly undertaken in women participating in reproductive medicine treatment because of the nature to obtain the specimen. In most studies follicular fluids have been pooled for analysis. Information on separately collected follicular fluids is still rare. We hypothesized that the composition of bacteria within follicular fluids is responsible for the success of the fertilization process. Study design, size, duration The study was designed and conducted at the Kinderwunsch Institut Schenk GmbH (Dobl, Austria) together with DNA-Technology. Follicular fluids from 46 patients undergoing IVF (in vitro fertilization) and ICSI (intracytoplasmic sperm injection) treatment were included and analyzed. Participants/materials, setting, methods Follicular fluids from 46 patients were collected separately. 2 follicular fluids from each patient were screened for common bacteria of the genital tract. One from an oocyte developing a good quality blastocyst and one displaying fertilization failures. Samples were analyzed for bacterial composition using the Femoflor16 (DNA-Technology). Main results and the role of chance Quantitative analysis revealed a higher total bacteria mass in follicles from oocytes that failed fertilization. Furthermore, Lactobacillus were not present in those follicles compared to good blastocyst follicles. In addition, Chlamydia trachomatis was found mainly in follicular fluid of not fertilized oocytes together with Eubacterium, Gardnarella and Trichomonas species. Interestingly, a trend of elevated levels of Ureaplasma species in follicular fluids of oocytes developing good quality blastocysts was observed. Limitations, reasons for caution Contamination of follicular fluids due to the procedure of oocyte pick up and follicular fluid retrieval cannot be completely excluded. Results should be confirmed with a higher sample size. Wider implications of the findings: We assume that different bacterial compositions in follicular fluids are responsible for the destiny of the oocyte. It is tempting to speculate that bacterial analysis of follicular fluids may be beneficial to select to best oocytes in future IVF/ICSI treatments. Trial registration number Not applicable

scholarly journals Dynamic Expression of Interleukin-33 and ST2 in the Mouse Reproductive Tract Is Influenced by Superovulation

2020 ◽  
Vol 68 (4) ◽  
pp. 253-267
Author(s):  
Salma Begum ◽  
Barry E. Perlman ◽  
Nuriban Valero-Pacheco ◽  
Valerie O’Besso ◽  
Tracy Wu ◽  
...  
Keyword(s):  
Estrous Cycle ◽  
Reproductive Tract ◽  
Ovarian Function ◽  
Expression Patterns ◽  
Follicular Development ◽  
Female Reproductive Tract ◽  
Soluble Form ◽  
Vitro Fertilization ◽  
Interleukin 33

Interleukin-33 (IL-33) is an IL-1 family cytokine with pleiotropic effects on diverse cell types. Dysregulated IL-33 signaling has been implicated in pregnancy-related disorders, including preeclampsia and recurrent pregnancy loss, and in ovarian function in women undergoing controlled ovarian stimulation for in vitro fertilization. To date, expression of IL-33 and its receptor subunit, ST2, in the female reproductive tract remains poorly characterized. We identify IL-33-expressing oocytes surrounded by ST2-expressing granulosa cells at all stages of follicular development, in addition to IL-33+ and ST2+ non-endothelial cells in the ovarian stroma and theca layer in ovaries from adult mice. These expression patterns are similar in estrus- and diestrus-stage adults and in pubescent mice, suggesting a role for IL-33 signaling in ovarian function throughout development and in the estrous cycle. In the uterus, we find expression of IL-33 and ST2 in glandular and luminal epithelia during estrus and at the initiation of pregnancy. Uterine IL-33 expression was modulated by the estrous cycle and was reduced in pubescent females. Last, superovulation increases transcripts for IL-33 and the soluble form of ST2 (sST2) in ovaries, and for IL-33 in uteri. Collectively, our findings lay the foundation for studies identifying cell type-specific requirements for IL-33/ST2 signaling in the establishment and maintenance of mouse pregnancy.

scholarly journals LYPD4, mouse homolog of a human acrosome protein, is essential for sperm fertilizing ability and male fertility†

2020 ◽  
Vol 102 (5) ◽  
pp. 1033-1044
Author(s):  
Dan Wang ◽  
Liping Cheng ◽  
Wenjuan Xia ◽  
Xiaofei Liu ◽  
Yueshuai Guo ◽  
...  
Keyword(s):  
Male Fertility ◽  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Mass Spectrometry Analysis ◽  
Small Subset ◽  
Vitro Fertilization ◽  
Spectrometry Analysis ◽  
Human Fertilization ◽  
Sperm Migration

Abstract Fertilization is one of the fundamental biological processes, but so far, we still do not have a full understanding of the underlying molecular mechanism. We have identified a human acrosome protein, LY6/PLAUR domain containing 4 (LYPD4), expressed specifically in human testes and sperm, and conserved within mammals. Mouse Lypd4, also specific to the testis and sperm, is essential for male fertility. LYPD4 protein first appeared in round spermatids during acrosome biogenesis and became part of acrosomes during spermatogenesis and in mature sperm. Lypd4 knockout mice are infertile with normal sperm number and motility. Mutant sperm, however, failed to reach oviduct during sperm migration inside the female reproductive tract, leading to fertilization failure and infertility. In addition, Lypd4 mutant sperms were unable to fertilize denuded egg via IVF (in vitro fertilization) but could fertilize eggs within intact Cumulus-Oocyte Complex, supporting an additional role in sperm-zona interaction. Out of more than five thousand spermatozoa proteins identified by mass spectrometry analysis, only a small subset of proteins (26 proteins) was changed in the absence of LYPD4, revealing a whole proteome picture of mutant sperm defective in sperm migration and sperm-zona binding. ADAM3, a key component of fertilization complex, as well as other sperm ADAM proteins are significantly reduced. We hence propose that LYPD4 plays an essential role in mammalian fertilization, and further investigation of its function and its interaction with other sperm membrane complexes may yield insights into human fertilization and novel strategy to improve IVF success.

scholarly journals Microgrooves and fluid flows provide preferential passageways for sperm over pathogen Tritrichomonas foetus

2015 ◽  
Vol 112 (17) ◽  
pp. 5431-5436 ◽  
Author(s):  
Chih-kuan Tung ◽  
Lian Hu ◽  
Alyssa G. Fiore ◽  
Florencia Ardon ◽  
Dillon G. Hickman ◽  
...  
Keyword(s):  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Tritrichomonas Foetus ◽  
Reproductive Process ◽  
Near Surface ◽  
Vitro Fertilization ◽  
Sexually Transmitted ◽  
Posterior Flagellum ◽  
Sperm Migration

Successful mammalian reproduction requires that sperm migrate through a long and convoluted female reproductive tract before reaching oocytes. For many years, fertility studies have focused on biochemical and physiological requirements of sperm. Here we show that the biophysical environment of the female reproductive tract critically guides sperm migration, while at the same time preventing the invasion of sexually transmitted pathogens. Using a microfluidic model, we demonstrate that a gentle fluid flow and microgrooves, typically found in the female reproductive tract, synergistically facilitate bull sperm migration toward the site of fertilization. In contrast, a flagellated sexually transmitted bovine pathogen, Tritrichomonas foetus, is swept downstream under the same conditions. We attribute the differential ability of sperm and T. foetus to swim against flow to the distinct motility types of sperm and T. foetus; specifically, sperm swim using a posterior flagellum and are near-surface swimmers, whereas T. foetus swims primarily via three anterior flagella and demonstrates much lower attraction to surfaces. This work highlights the importance of biophysical cues within the female reproductive tract in the reproductive process and provides insight into coevolution of males and females to promote fertilization while suppressing infection. Furthermore, the results provide previously unidentified directions for the development of in vitro fertilization devices and contraceptives.

scholarly journals Co-Adaptation of Physical Attributes of the Mammalian Female Reproductive Tract and Sperm to Facilitate Fertilization

Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1297
Author(s):  
Chih-Kuan Tung ◽  
Susan S. Suarez
Keyword(s):  
Reproductive Tract ◽  
Fluid Flows ◽  
Fertilization Success ◽  
Female Reproductive Tract ◽  
Vitro Fertilization ◽  
Invasive Pathogens ◽  
Sperm Migration ◽  
Physical Attributes ◽  
Mammalian Female

The functions of the female reproductive tract not only encompass sperm migration, storage, and fertilization, but also support the transport and development of the fertilized egg through to the birth of offspring. Further, because the tract is open to the external environment, it must also provide protection against invasive pathogens. In biophysics, sperm are considered “pusher microswimmers”, because they are propelled by pushing fluid behind them. This type of swimming by motile microorganisms promotes the tendency to swim along walls and upstream in gentle fluid flows. Thus, the architecture of the walls of the female tract, and the gentle flows created by cilia, can guide sperm migration. The viscoelasticity of the fluids in the tract, such as mucus secretions, also promotes the cooperative swimming of sperm that can improve fertilization success; at the same time, the mucus can also impede the invasion of pathogens. This review is focused on how the mammalian female reproductive tract and sperm interact physically to facilitate the movement of sperm to the site of fertilization. Knowledge of female/sperm interactions can not only explain how the female tract can physically guide sperm to the fertilization site, but can also be applied for the improvement of in vitro fertilization devices.

scholarly journals OVARIAN GRANULOSA CELLS FROM WOMEN WITH PCOS EXPRESS LOW LEVELS OF SARS-COV-2 RECEPTORS AND CO-FACTORS

2021 ◽  
Author(s):  
Aalaap Anand Naigaonkar ◽  
Krutika Madhukar Patil ◽  
Shaini Joseph ◽  
Indira Hinduja ◽  
Srabani Mukherjee
Keyword(s):  
Granulosa Cells ◽  
Reproductive Tract ◽  
Polycystic Ovary ◽  
Ovarian Follicle ◽  
Cell Types ◽  
Female Reproductive Tract ◽  
Vitro Fertilization ◽  
Ovarian Granulosa Cells ◽  
Lower Expression

Purpose: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is global pandemic with more than 3 million deaths so far. Female reproductive tract organs express coronavirus-associated receptors and factors (SCARFs); suggesting they may be susceptible to SARS-CoV-2 infection however the susceptibility of ovary/follicle/oocyte to the same is still elusive. Co-morbidities like obesity, type-2 diabetes mellitus, cardiovascular disease etc. increase the risk of SARS-CoV-2 infection. These features are common in women with polycystic ovary syndrome (PCOS), warranting further scope to study SCARFs expression in ovary of these women. Materials and methods: SCARFs expression in ovary and ovarian tissues of women with PCOS and healthy women was explored by analyzing publically available microarray datasets. Transcript expression of SCARFs were investigated in mural and cumulus granulosa cells (MGCs and CGCs) from control and PCOS women undergoing in vitro fertilization (IVF). Results: Microarray data revealed that ovary expresses all genes necessary for SARS-CoV-2 infection. PCOS women mostly showed down-regulated/unchanged levels of SCARFs. MGCs and CGCs from PCOS women showed lower expression of receptors ACE2, BSG and DPP4 and protease CTSB than in controls. MGCs showed lower expression of protease CTSL in PCOS than in controls. Expression of TMPRSS2 was not detected in both cell types. Conclusions: Human ovarian follicle may be susceptible to SARS-CoV-2 infection. Lower expression of SCARFs in PCOS indicate that the risk of SARS-CoV-2 infection to the ovary may be lesser in these women than controls. This knowledge may help in safe practices at IVF settings in the current pandemic. Keywords: SARS-CoV-2, COVID-19, Ovarian granulosa cells, Oocyte, PCOS, IVF

scholarly journals Caput Ligation Renders Immature Mouse Sperm Motile and Capable to Undergo cAMP-Dependent Phosphorylation

2021 ◽  
Vol 22 (19) ◽  
pp. 10241
Author(s):  
Darya A. Tourzani ◽  
Maria A. Battistone ◽  
Ana M. Salicioni ◽  
Sylvie Breton ◽  
Pablo E. Visconti ◽  
...  
Keyword(s):  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Sperm Maturation ◽  
Molecular Pathways ◽  
Epididymal Sperm ◽  
Mammalian Sperm ◽  
Maturation In Vitro ◽  
Epididymal Maturation ◽  
Immature Mouse

Mammalian sperm must undergo two post-testicular processes to become fertilization-competent: maturation in the male epididymis and capacitation in the female reproductive tract. While caput epididymal sperm are unable to move and have not yet acquired fertilization potential, sperm in the cauda epididymis have completed their maturation, can move actively, and have gained the ability to undergo capacitation in the female tract or in vitro. Due to the impossibility of mimicking sperm maturation in vitro, the molecular pathways underlying this process remain largely unknown. We aimed to investigate the use of caput epididymal ligation as a tool for the study of sperm maturation in mice. Our results indicate that after seven days of ligation, caput sperm gained motility and underwent molecular changes comparable with those observed for cauda mature sperm. Moreover, ligated caput sperm were able to activate pathways related to sperm capacitation. Despite these changes, ligated caput sperm were unable to fertilize in vitro. Our results suggest that transit through the epididymis is not required for the acquisition of motility and some capacitation-associated signaling but is essential for full epididymal maturation. Caput epididymal ligation is a useful tool for the study of the molecular pathways involved in the acquisition of sperm motility during maturation.

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