Computational modelling of maternal interactions with spermatozoa: potentials and prospects

2011 ◽  
Vol 23 (8) ◽  
pp. 976 ◽  
Author(s):  
Mark Burkitt ◽  
Dawn Walker ◽  
Daniela M. Romano ◽  
Alireza Fazeli
Keyword(s):  
Reproductive Tract ◽  
Computational Modelling ◽  
Female Reproductive Tract ◽  
In Vivo Experiments ◽  
Complex Interactions ◽  
Maternal Communication ◽  
In Silico Models

Understanding the complex interactions between gametes, embryos and the maternal tract is required knowledge for combating infertility and developing new methods of contraception. Here we present some main aspects of spermatozoa interactions with the mammalian oviduct before fertilisation and discuss how computational modelling can be used as an invaluable aid to experimental investigation in this field. A complete predictive computational model of gamete and embryo interactions with the female reproductive tract is a long way off. However, the enormity of this task should not discourage us from working towards it. Computational modelling allows us to investigate aspects of maternal communication with gametes and embryos, which are financially, ethically or practically difficult to look at experimentally. In silico models of maternal communication with gametes and embryos can be used as tools to complement in vivo experiments, in the same way as in vitro and in situ models.

scholarly journals 3D in situ imaging of the female reproductive tract reveals molecular signatures of fertilizing spermatozoa in mice

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Lukas Ded ◽  
Jae Yeon Hwang ◽  
Kiyoshi Miki ◽  
Huanan F Shi ◽  
Jean-Ju Chung
Keyword(s):  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Sperm Selection ◽  
Pharmacological Studies ◽  
Sperm Migration ◽  
Selection For ◽  
Insight Into

Out of millions of ejaculated sperm, a few reach the fertilization site in mammals. Flagellar Ca2+ signaling nanodomains, organized by multi-subunit CatSper calcium channel complexes, are pivotal for sperm migration in the female tract, implicating CatSper-dependent mechanisms in sperm selection. Here using biochemical and pharmacological studies, we demonstrate that CatSper1 is an O-linked glycosylated protein, undergoing capacitation-induced processing dependent on Ca2+ and phosphorylation cascades. CatSper1 processing correlates with protein tyrosine phosphorylation (pY) development in sperm cells capacitated in vitro and in vivo. Using 3D in situ molecular imaging and ANN-based automatic detection of sperm distributed along the cleared female tract, we demonstrate that spermatozoa past the utero-tubal junction possess the intact CatSper1 signals. Together, we reveal that fertilizing mouse spermatozoa in situ are characterized by intact CatSper channel, lack of pY, and reacted acrosomes. These findings provide molecular insight into sperm selection for successful fertilization in the female reproductive tract.

scholarly journals 3D in situ imaging of female reproductive tract reveals molecular signatures of fertilizing spermatozoa in mice

2020 ◽  
Author(s):  
Lukas Ded ◽  
Jae Yeon Hwang ◽  
Kiyoshi Miki ◽  
Huanan F. Shi ◽  
Jean-Ju Chung
Keyword(s):  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Sperm Selection ◽  
Pharmacological Studies ◽  
Sperm Migration ◽  
Selection For ◽  
Insight Into

AbstractOut of millions of ejaculated sperm, only a few reach the fertilization site in mammals. Flagellar Ca2+ signaling nanodomains, organized by multi-subunit CatSper calcium channel complexes, are pivotal for sperm migration in the female tract, implicating CatSper-dependent mechanisms in sperm selection. Here, using biochemical and pharmacological studies, we demonstrate that CatSper1 is an O-linked glycosylated protein, undergoing capacitation-induced processing dependent on Ca2+ and phosphorylation cascades. CatSper1 processing correlates with protein tyrosine phosphorylation (pY) development in sperm cells capacitated in vitro and in vivo. Using 3D in situ molecular imaging and ANN-based automatic detection of sperm distributed along the cleared female tract, we demonstrate that all spermatozoa past the UTJ possess intact CatSper1 signals. Together, we reveal that fertilizing mouse spermatozoa in situ are characterized by intact CatSper channel, lack of pY, and reacted acrosomes. These findings provide molecular insight into sperm selection for successful fertilization in the female reproductive tract.

scholarly journals Enlisting the Ixodes scapularis Embryonic ISE6 Cell Line to Investigate the Neuronal Basis of Tick—Pathogen Interactions

Pathogens ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 70
Author(s):  
Lourdes Mateos-Hernández ◽  
Natália Pipová ◽  
Eléonore Allain ◽  
Céline Henry ◽  
Clotilde Rouxel ◽  
...  
Keyword(s):  
Cell Line ◽  
Peripheral Nerves ◽  
Ixodes Scapularis ◽  
Embryonic Cell ◽  
Cell Subpopulation ◽  
In Vivo Experiments

Neuropeptides are small signaling molecules expressed in the tick central nervous system, i.e., the synganglion. The neuronal-like Ixodes scapularis embryonic cell line, ISE6, is an effective tool frequently used for examining tick–pathogen interactions. We detected 37 neuropeptide transcripts in the I. scapularis ISE6 cell line using in silico methods, and six of these neuropeptide genes were used for experimental validation. Among these six neuropeptide genes, the tachykinin-related peptide (TRP) of ISE6 cells varied in transcript expression depending on the infection strain of the tick-borne pathogen, Anaplasma phagocytophilum. The immunocytochemistry of TRP revealed cytoplasmic expression in a prominent ISE6 cell subpopulation. The presence of TRP was also confirmed in A. phagocytophilum-infected ISE6 cells. The in situ hybridization and immunohistochemistry of TRP of I. scapularis synganglion revealed expression in distinct neuronal cells. In addition, TRP immunoreaction was detected in axons exiting the synganglion via peripheral nerves as well as in hemal nerve-associated lateral segmental organs. The characterization of a complete Ixodes neuropeptidome in ISE6 cells may serve as an effective in vitro tool to study how tick-borne pathogens interact with synganglion components that are vital to tick physiology. Therefore, our current study is a potential stepping stone for in vivo experiments to further examine the neuronal basis of tick–pathogen interactions.

Phosphofructokinase activity and acidosis during short-term tetanic contractions

1991 ◽  
Vol 69 (2) ◽  
pp. 298-304 ◽  
Author(s):  
Lawrence L. Spriet
Keyword(s):  
Glycolytic Enzyme ◽  
Test Tube ◽  
Mammalian Skeletal Muscle ◽  
Short Term ◽  
Short Supply ◽  
In Vivo Experiments ◽  
Anaerobic Energy

Anaerobic energy production is essential for the production of muscular tension when the demand for energy is greater than can be provided aerobically and when oxygen is in short supply. The largest source of anaerobic energy is from the glycolytic pathway. With sustained tetanic contractions, muscle glycolytic activity is high and hydrogen ions (H+) accumulate while tension production decreases. The increasing [H+] and decreasing tension led to the suggestion that H+ inhibits the activity of the regulatory glycolytic enzyme phosphofructokinase (PFK). Early in vitro work confirmed the H+ sensitivity of PFK in the test tube, indicating that little PFK activity should persist at a pH of 6.9–7.0. However, in situ and in vivo experiments suggested that significant PFK activity was maintained during intense contractions when muscle pH decreased to 6.4–6.6. There are several concerns associated with the application of in vitro findings to in vivo exercise situations: (i) there is little in vitro work in mammalian skeletal muscle with substrate and modulator concentrations representative of exercise, (ii) most in vitro analyses of PFK activity are performed following the dilution of the enzyme in mediums with low protein concentration, and (iii) do the modulators identified in vitro exist in high enough in vivo concentrations at rest and during exercise to contribute to the regulation of PFK? More recent in vitro and in situ PFK experiments have overcome some of these concerns. They confirm that during intense, short-term tetanic contractions, PFK activity is well matched to the ATP demand despite decreases in pH to ~6.4–6.5. A combination of decreased inhibitor (ATP) and increased substrate (fructose 6-phosphate) contents coupled with increases in the contents of several positive modulators may be responsible for the maintained PFK activity. This combination reduces the pH-dependent ATP inhibition of PFK and extends the physiological pH range of the enzyme to the range normally measured during this type of muscular activity.Key words: glycolysis, phosphofructokinase, anaerobic metabolism, acidosis.

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.

301 THE EFFECT OF EQUINE FOLICULLAR FLUID ON IN VITRO INDUCTION OF THE ACROSOME REACTION IN FROZEN - THAWED STALLION SPERMATOZOA

2010 ◽  
Vol 22 (1) ◽  
pp. 307
Author(s):  
D. S. Silva ◽  
P. Rodriguez ◽  
N. S. Arruda ◽  
R. Rodrigues ◽  
J. L. Rodrigues
Keyword(s):  
Contact Area ◽  
Follicular Fluid ◽  
Acrosome Reaction ◽  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Heparin Group ◽  
Fluorescent Stain ◽  
In Vitro Induction

The capacitation process occurs in vivo upon exposure of the spermatozoa through the female reproductive tract, but can be induced in vitro in the presence of several compounds. This study was conducted to assess the effect of heparin or equine follicular fluid on hyperactivated motility and in vitro induction acrosome reaction swim-up method with frozen-thawed stallion semen. Two hundred microliters of frozen-thawed equine semen was placed in a tube (45°C) to increase contact area and incubated at 37°C for 1 h. After incubation 800 μL of the supernatant was collected by centrifugation (500 × g, 10 min) to collect spermatozoa. The resulting pellet was resuspended in capacitation medium Fert-TALP supplemented with 5.0 μg mL-1 heparin or 100% follicular fluid and incubated for different times (1, 2, 3, 4, and 5 h) at 37°C. After incubation the hyperactivated motility and acrosome-reacted spermatozoa were evaluated. Hoechst stain was used to differentiate live and dead spermatozoa, and chlortetracycline (CTC) fluorescent stain was used to assess the capacitation response of sperm; data were analyzed by ANOVA. The effect of equine follicular fluid resulted in improved percentage of spermatozoa with acrosome reaction at all times of incubation (60, 63, 57, 52, and 58%) but immediately after 3 h of incubation, the hyperactivated motility decreased in heparin group and follicular fluid (42 and 30%, respectively).

scholarly journals ESR1 Mutations Associated With Estrogen Insensitivity Syndrome Change Conformation of Ligand-Receptor Complex and Altered Transcriptome Profile

Endocrinology ◽  
2020 ◽  
Vol 161 (6) ◽  
Author(s):  
Yin Li ◽  
Katherine J Hamilton ◽  
Lalith Perera ◽  
Tianyuan Wang ◽  
Artiom Gruzdev ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Reproductive Tract ◽  
Biological Effects ◽  
Estrogen Receptor Α ◽  
Female Reproductive Tract ◽  
Receptor Complexes ◽  
Esr1 Gene ◽  
Esr1 Mutations

Abstract Estrogen insensitivity syndrome (EIS) arises from rare mutations in estrogen receptor-α (ERα, encoded by ESR1 gene) resulting in the inability of estrogen to exert its biological effects. Due to its rarity, mutations in ESR1 gene and the underlying molecular mechanisms of EIS have not been thoroughly studied. Here, we investigate known ESR1 mutants, Q375H and R394H, associated with EIS patients using in vitro and in vivo systems. Comparison of the transcriptome and deoxyribonucleic acid methylome from stable cell lines of both Q375H and R394H clinical mutants shows a differential profile compared with wild-type ERα, resulting in loss of estrogen responsiveness. Molecular dynamic simulation shows that both ESR1 mutations change the ERα conformation of the ligand-receptor complexes. Furthermore, we generated a mouse model Esr1-Q harboring the human mutation using CRISPR/Cas9 genome editing. Female and male Esr1-Q mice are infertile and have similar phenotypes to αERKO mice. Overall phenotypes of the Esr1-Q mice correspond to those observed in the patient with Q375H. Finally, we explore the effects of a synthetic progestogen and a gonadotropin-releasing hormone inhibitor in the Esr1-Q mice for potentially reversing the impaired female reproductive tract function. These findings provide an important basis for understanding the molecular mechanistic consequences associated with EIS.

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.

scholarly journals In vivo exposure to 17β-estradiol triggers premature sperm capacitation in cauda epididymis

Reproduction ◽  
2013 ◽  
Vol 145 (3) ◽  
pp. 255-263 ◽  
Author(s):  
Lukas Ded ◽  
Natasa Sebkova ◽  
Martina Cerna ◽  
Fatima Elzeinova ◽  
Pavla Dostalova ◽  
...  
Keyword(s):  
Reproductive Tract ◽  
Negative Impact ◽  
Reproductive Potential ◽  
Female Reproductive Tract ◽  
Sperm Capacitation ◽  
Epididymal Sperm ◽  
Knock Out ◽  
17Β Estradiol

Estrogens play a crucial role in spermatogenesis and estrogen receptor α knock-out male mice are infertile. It has been demonstrated that estrogens significantly increase the speed of capacitation in vitro; however this may lead to the reduction of reproductive potential due to the decreased ability of these sperm to undergo the acrosome reaction. To date the in vivo effect of estrogens on the ability of sperm to capacitate has not been investigated. Therefore, in this study, we exposed mice (n=24) to 17β-estradiol (E2) at the concentration of 20 ng/ml either during puberty from the fourth to seventh week of age (n=8), or continuously from birth for a period of 12 weeks (n=8) at which age the animals from both groups were killed. The capacitation status of epididymal and testicular sperm was analysed by tyrosine phosphorylation (TyrP) antibody (immunofluorescence and western blot) and chlortetracycline (CTC) assay. According to our results, in vivo exposure to increased E2 concentrations caused premature sperm capacitation in the epididymis. The effect of E2, however, seems reversible because after the termination of the exposure premature epididymal sperm capacitation is decreased in animals treated during puberty. Furthermore the changes in epididymal sperm capacitation status detected by TyrP and CTC positively correlate with plasma levels of E2 and the expression of the estrogen-dependent trefoil factor 1 (Tff1) gene in testicular tissue. Therefore, our data implicate that in vivo exposure to E2 under specific conditions leads to the premature capacitation of mouse sperm in epididymis with a potential negative impact on the sperm reproductive fitness in the female reproductive tract.

scholarly journals In vitro 3D Model of Female Reproductive Tract: An Overview and Future Aspect

2021 ◽  
Author(s):  
Arnaud Martino Capuzzo
Keyword(s):  
Reproductive Tract ◽  
Three Dimensional ◽  
Reproductive Organs ◽  
Experimental Models ◽  
Female Reproductive Tract ◽  
Complex Interactions ◽  
Current State ◽  
Pregnancy And Delivery ◽  
Recent Developments

Hormones must be balanced and dynamically controlled for the Female Reproductive Tract (FRT) to function correctly during the menstrual cycle, pregnancy, and delivery. Gamete selection and successful transfer to the uterus, where it implants and pregnancy occurs, is supported by the mucosal epithelial lining of the FRT ovaries, uterus, cervix, fallopian tubes, and vagina. Successful implantation and placentation in humans and other animals rely on complex interactions between the embryo and a receptive female reproductive system. The FRT's recent breakthroughs in three-dimensional (3D) organoid systems now provide critical experimental models that match the organ's physiological, functional, and anatomical characteristics in vitro. This article summarizes the current state of the art on organoids generated from various parts of the FRT. The current analysis examines recent developments in the creation of organoid models of reproductive organs, as well as their future directions.

Sign in / Sign up

Export Citation Format

Share Document