As sperm production is costly, males are expected to strategically allocate resources to sperm production according to mating opportunities. While sperm number adjustments have been reported in several taxa, only a few studies investigated whether sperm quality shows adaptive plasticity as well. We tested this prediction in the guppy, Poecilia reticulata. A total of 46 males were initially stripped of all retrievable sperm before being randomly allocated to one of two treatments simulating different levels of mating opportunities (visual contact with females or female deprived). After 3 days, males were stripped and sperm velocity was assayed using Computer Assisted Sperm Analysis. Males in the presence of females produced significantly faster sperm than their counterparts. Implications for the evolution of this ejaculate plasticity in the light of results of sperm competition studies are discussed.
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http://dx.doi.org/10.1098/rsbl.2009.0413 | DOI Listing |
ACS Nano
January 2025
Department of Urology, Peking University First Hospital, Beijing 100034, China.
Although considered an "eco-friendly" biodegradable plastic, polylactic acid (PLA) microplastic (PLA-MP) poses a growing concern for human health, yet its effects on male reproductive function remain underexplored. This study investigated the reproductive toxicity of PLA in male mice and its potential mechanisms. To this end, our in vivo and in vitro experiments demonstrated that after degradation in the digestive system, a significant number of PLA-MP-derived nanoparticles could penetrate the blood-testis barrier (BTB) and localize within the spermatogenic microenvironment.
View Article and Find Full Text PDFPLoS One
January 2025
Laboratory of Developmental Biology, Department of Morphology and Genetics-Paulista Medicine School, Federal University of Sao Paulo (UNIFESP), Sao Paulo, SP, Brazil.
Melatonin is a pineal hormone synthesized exclusively at night, in several organisms. Its action on sperm is of particular interest, since they transfer genetic and epigenetic information to the offspring, including microRNAs, configuring a mechanism of paternal epigenetic inheritance. MicroRNAs are known to participate in a wide variety of mechanisms in basically all cells and tissues, including the brain and the sperm cells, which are known, respectively, to present 70% of all identified microRNAs and to transfer these molecules to the embryo.
View Article and Find Full Text PDFReprod Fertil
January 2025
M Bazrgar, Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran., Tehran, Iran (the Islamic Republic of).
It is believed that aneuploid embryos release cell-free DNA (cfDNA) into the blastocyst cavity during the self-correction process through the apoptotic mechanism. This study aimed to develop less invasive methods for predicting ploidy status by investigating how ploidy status affects blastocoel fluid DNA (BF-DNA) levels and apoptotic gene expression as indicators of embryo viability. Human blastocysts were classified into three groups; Survivable Embryo (SE), Fatal Single and double Aneuploidy (FSDA), and Multiple Aneuploidy (MA) using array comparative genomic hybridization (array-CGH) by trophectoderm (TE) biopsy.
View Article and Find Full Text PDFMicrobiol Spectr
January 2025
School of Public Health, the Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, Guizhou, China.
Unlabelled: Backed by advancements in technologies like microbial sequencing, many studies indicate that the vaginal microbiome is a key marker of female reproductive health. However, further studies are still needed to investigate the correlation between vaginal microbiota (VMB) and outcomes of assisted reproductive technology (ART). Therefore, this study compared the VMB of two types of infertile women undergoing fertilization (IVF) with normal control women during the implantation window period and investigated the effects of VMB characteristics on IVF outcomes.
View Article and Find Full Text PDFNucleic Acids Res
January 2025
Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong 226001, China.
Chromatin remodeling, which involves the histone-to-protamine exchange process during spermiogenesis, is crucial for sperm nuclear condensation and male fertility. However, the key regulators and underlying molecular mechanisms involved in this process remain largely unexplored. In this study, we discovered that deficiency in the family with sequence similarity 170 member A (Fam170a) led to abnormal sperm nuclear morphology and male infertility in mice, mirroring the observation of very low Fam170a transcription levels in sperm of infertile men with teratozoospermia.
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