To determine where and when hyperactivation is initiated in vivo, the flagellar curvature ratios (fcr) of mouse sperm within the female reproductive tract were measured from videotape recordings and compared with those of epididymal sperm incubated under capacitating conditions in vitro. The fcrs and linearities of trajectory were significantly lowered after 90 min of incubation in vitro, indicating that hyperactivation had been initiated by that time. The flagellar curvature ratios of sperm at the colliculus tubarius, within the uterotubal junction, and in the isthmus, measured at 1-2 h postcoitus and approximately 1 h before and 1 h after ovulation, were found to have fcrs that were not different from those of sperm incubated for 90 min in vitro. It was concluded that the tract sperm had initiated hyperactivated flagellar bending before the time of ovulation and before entering the oviduct. Only sperm in the lower isthmus 1 h before ovulation had fcrs that were significantly different from sperm incubated for 90 min in vitro, but not from sperm measured at the beginning of incubation in vitro. This could be the result of motility suppression in the lower isthmus.
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http://dx.doi.org/10.1095/biolreprod36.5.1191 | DOI Listing |
Andrology
January 2025
Department of Surgery, Division of Urology, Human Reproduction Section, São Paulo Federal University, São Paulo, Brazil.
Background: Varicocele is associated with a progressive decrease in male fertile potential, but it has yet to be determined if the duration of varicocele is associated with altered sperm functional quality.
Objectives: This experimental study investigated the time-dependent effects of varicocele on spermatogenesis, sperm parameters, and sperm functional traits.
Materials And Methods: Thirty-five mature male Wistar rats (200 ± 25 g) were included.
iScience
January 2025
Institute of Marine Sciences, Spanish National Research Council (CSIC), 08003 Barcelona, Spain.
Translational silence of spermatozoa has long been considered the norm in animals. However, studies in mammals have shown that the mitochondrial ribosomal machinery is selectively activated during capacitation in the female reproductive tract, while cytosolic ribosomes remain inactive. Here, using quantitative proteomics in a piscine model species, we show that proteins involved in mRNA processing and cytoplasmic translation are predominantly accumulated in immature spermatozoa within the extratesticular excurrent ducts, while those related to flagellar motility are enriched in ejaculated (mature) sperm.
View Article and Find Full Text PDFTheriogenology
January 2025
Department of Animal Science and Biotechnology, Kyungpook National University, Sangju, 37224, Republic of Korea; Research Institute for Innovative Animal Science, Kyungpook National University, Sangju, 37224, Republic of Korea. Electronic address:
Spermatozoa must undergo a complex maturation process within the female genital tract known as capacitation. This process entails the phosphorylation or dephosphorylation of various proteins, and multiple signaling pathways are recognized to play a role. The present study aims to identify alterations in the expression of proteins related to the phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT) signaling pathway and assess sperm functions during capacitation.
View Article and Find Full Text PDFHum Reprod
January 2025
IRSD, Université de Toulouse, INSERM, INRAE, ENVT, Univ Toulouse III-Paul Sabatier (UPS), Toulouse, France.
Study Question: Does a human fallopian tube (HFT) organoid model offer a favourable apical environment for human sperm survival and motility?
Summary Answer: After differentiation, the apical compartment of a new HFT organoid model provides a favourable environment for sperm motility, which is better than commercial media.
What Is Known Already: HFTs are the site of major events that are crucial for achieving an ongoing pregnancy, such as gamete survival and competence, fertilization steps, and preimplantation embryo development. In order to better understand the tubal physiology and tubal factors involved in these reproductive functions, and to improve still suboptimal in vitro conditions for gamete preparation and embryo culture during IVF, we sought to develop an HFT organoid model from isolated adult stem cells to allow spermatozoa co-culture in the apical compartment.
J Hypertens
December 2024
Institute for Fetology, The First Affiliated Hospital of Soochow University, Jiangsu.
Background: Paternal preconception alcohol exposure affects fetal development; however, it is largely unknown about the influences on offspring vasculature and mechanisms.
Methods: Offspring born form paternal rats treated with alcohol or water before pregnant was raised until 3 months of age. Vessel tone of mesenteric arteries was detected using myograph system; whole-cell calcium channel current in smooth muscle cells was tested using patch-clamp; molecule expressions were detected with real-time PCR, western blotting, and Dihydroethidium (DHE); DNA methylations were determined using targeted bisulfate sequencing assay.
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