Publications by authors named "Darya A Tourzani"

To become fertile, mammalian sperm are required to undergo capacitation in the female tract or in vitro in defined media containing ions (e.g. HCO3 -, Ca2+, Na+, and Cl-), energy sources (e.

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Background: Phthalates have been linked to adverse male reproductive health, including poor sperm quality and embryo quality as well as a longer time to pregnancy (months of unprotected intercourse before conception occurs). The present study aimed to evaluate the effect of preconception exposure to two ubiquitous phthalate chemicals, di(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP), and their mixture on sperm function, fertilization, and embryo development in mice.

Materials And Methods: Adult male C57BL/6J mice aged 8-9 weeks were exposed to di(2-ethylhexyl) phthalate, di-n-butyl phthalate, or their mixture (di-n-butyl phthalate + di(2-ethylhexyl) phthalate) at 2.

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The sperm energy restriction and recovery (SER) treatment developed in our laboratory was shown to improve fertilization and blastocyst development following in vitro fertilization (IVF) in mice. Here, we investigated the effects of SER on early embryogenesis. Developmental events observed during the first cell cycle indicated that progression through the pronuclear stages of SER-generated embryos is advanced in comparison with control-generated embryos.

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The CatSper cation channel is essential for sperm capacitation and male fertility. The multi-subunit CatSper complexes form highly organized calcium signaling nanodomains on flagellar membranes. Here, we report identification of an uncharacterized protein, C2CD6, as a subunit of the mouse CatSper complex.

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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.

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We have previously shown that members of the family of testis-specific serine/threonine kinases (TSSKs) are post-meiotically expressed in testicular germ cells and in mature sperm in mammals. The restricted post-meiotic expression of TSSKs as well as the importance of phosphorylation in signaling processes strongly suggest that TSSKs have an important role in germ cell differentiation and/or sperm function. This prediction has been supported by the reported sterile phenotype of the TSSK6 knock-out (KO) mice and of the double TSSK1/TSSK2 KO.

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Mammalian sperm have to undergo capacitation to fertilize the egg. At the molecular level, capacitation involves cAMP synthesis, protein kinase A activation, and downstream increase in tyrosine phosphorylation. In addition, during capacitation, mammalian sperm actively generate reactive oxygen species (ROS).

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The X-linked gene plays major roles in female mouse development and reproduction, where it is crucial for the maintenance of imprinted X chromosome inactivation in extraembryonic tissues of embryos. However, while females carrying a systemic knockout (KO) die around implantation, male KO mice appear healthy and are fertile. Here, we report an important role for in testis where it is highly expressed in post-meiotic round spermatids as well as in Sertoli cells.

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Male contraception is a very active area of research. Several hormonal agents have entered clinical trials, while potential non-hormonal targets have been brought to light more recently and are at earlier stages of development. The general strategy is to target genes along the molecular pathways of sperm production, maturation, or function, and it is predicted that these novel approaches will hopefully lead to more selective male contraceptive compounds with a decreased side effect burden.

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To become fertile, mammalian sperm must undergo a series of biochemical and physiological changes known as capacitation. These changes involve crosstalk between metabolic and signaling pathways and can be recapitulated . In this work, sperm were incubated in the absence of exogenous nutrients (starved) until they were no longer able to move.

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Mammalian sperm undergo a series of biochemical and physiological changes collectively known as capacitation in order to acquire the ability to fertilize. Although the increase in phosphorylation associated with mouse sperm capacitation is well established, the identity of the proteins involved in this signaling cascade remains largely unknown. Tandem mass spectrometry (MS/MS) has been used to identify the exact sites of phosphorylation and to compare the relative extent of phosphorylation at these sites.

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After leaving the testis, sperm undergo two sequential maturational processes before acquiring fertilizing capacity: sperm maturation in the male epididymis, and sperm capacitation in the female reproductive tract. During their transit through the epididymis, sperm experience several maturational changes; the acquisition of motility is one of them. The molecular basis of the regulation of this process is still not fully understood.

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