Biology subjects

Grechi, N.

Publications and source records attributed to Grechi, N..

3 recordsLinked to original sources

bioRxiv2023

Microplastics are detected in bull and dog sperm and polystyrene microparticles impair sperm fertilization

The alarming increase in global infertility rates has coincided with the pervasive accumulation of microplastics (MPs) resulting from the poor management of plastic waste. This concerning trend is particularly troubling because only 10% of male infertility cases can be attributed to identifiable causes, leaving a significant knowledge gap in our understanding of their underlying factors. To bridge this critical gap, it is important to explore the connection between the accumulation of MPs and the observed decline in male fertility. Here, the presence of microplastics in reproductive fluids from bulls and dogs was assessed and used as baseline concentrations for bull sperm exposure. Bovine epididymal sperm (ES) presented a mean of 72.5 MP particles mL-1 (0.3691 g mL-1) while canine seminal plasma had an average of 35.4 MP particles mL-1 (0.0066 g mL-1). Bovine sperm was exposed to three different concentrations of a mixture of 1.1, 0.5, and 0.3 {micro}m polystyrene (PS) beads: (1) 0.7 g mL-1, blood concentration of PS in cows (bPS); (2) 0.37 g mL-1, concentration of total MPs in ES (esMP); and (3) 0.026 g mL-1, concentration of PS in ES (esPS). All sperm samples incubated with PS exhibited reduced motility compared with the CT at 0.5 h. However, PS exposure did not affect acrosome or induced oxidative stress. When used for in vitro fertilization, the sperm exposed to PS had decreased blastocyst rates, in addition to inducing ROS formation and apoptosis on resulting embryos. By employing realistic exposure concentrations, this research sought to shed light on the comprehensive impact of MPs on bovine sperm and the quality of resulting embryos, providing the first evidence of MPs in bovine and dog sperm and demonstrating the detrimental effect of PS MPs on sperm motility and functionality. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=80 SRC="FIGDIR/small/571802v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@5871acorg.highwire.dtl.DTLVardef@8ee9f2org.highwire.dtl.DTLVardef@a1416borg.highwire.dtl.DTLVardef@cde261_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIMicroplastics were found across the most diverse range of environments and their presence have been shown to affect reproductive parameters within different species. C_LIO_LITrue-to-life concentrations of exposure were used to assess the potential effects of polystyrene in sperm parameters and fertilization. C_LIO_LIPolystyrene microplastics attach to sperm and decrease motility, also reducing sperm functionality as seen by decreased blastocyst rate and increased oxidative stress in embryos. C_LI

developmental biology↗

bioRxiv2023

Mechanical Properties of Native and Decellularized Reproductive Tissues: Insights for Tissue Engineering Strategies

Understanding the mechanical properties and porosity of reproductive tissues is vital for regenerative medicine in tissue engineering. This study investigated the changes in Youngs modulus (YM), storage modulus (E'), loss modulus (E''), and porosity of native and decellularized bovine reproductive tissues during the estrous cycle. Testis tunica albuginea had significantly higher YM, E', and E'' than the inner testis, indicating greater stiffness and viscoelasticity. Endometrium showed no distinct differences in YM, E', or E' across the estrous cycle or between horns. Ovaries exhibited significant variations in YM, E', E'', and porosity, with higher YM and E' in the ipsilateral cortex and medulla during the luteal phase. Decellularized ovarian tissues displayed increased porosity. The oviduct displayed no significant differences in YM or E' in the isthmus, but the contralateral ampulla had reduced YM and E' in the luteal phase. These findings offer valuable insights into the dynamic mechanical properties and porosity of reproductive tissues, facilitating the development of biomimetic scaffolds for tissue engineering applications.

bioengineering↗

bioRxiv2022

Microplastics are present in follicular fluid and compromise gamete function in vitro: Is the Anthropocene throw-away society throwing away fertility?

The past several decades have seen alarming declines in the reproductive health of humans, animals and plants. While humans have introduced numerous pollutants that can impair reproductive systems (such as well-documented endocrine disruptors), the potential for microplastics (MPs) to be contributing to the widespread declines in fertility is particularly noteworthy. Over the same timespan that declines in fertility began to be documented, there has been a correlated shift towards a "throw-away society" that is characterised by the excessive consumption of single-use plastic products and a concomitant accumulation of MPs pollution. Studies are showing that MPs can impair fertility, but data have been limited to rodents that were force-fed hundreds of thousands of times more plastics than they would be exposed in the environment. As a first step to link in vitro health effects with in vivo environmental exposure, we quantified microplastics in the follicular fluid of women and domestic cows. We found that the concentrations of polystyrene microplastics that naturally occurred in follicular fluid were sufficient to compromise the maturation of bovine oocytes in vitro. Collectively, these findings demonstrate that microplastics may also be contributing to the widespread declines in fertility that have been occurring over recent Anthropocene decades.

developmental biology↗