BACKGROUND: Bisphenol S (BPS) is increasingly used as a replacement for bisphenol A in the manufacture of products containing polycarbonates and epoxy resins. However, further studies of BPS exposure are needed for the assessment of health risks to humans. In this study we assessed the potential harmfulness of low-dose BPS on reproduction in male mice. METHODS: To simulate human exposure under experimental conditions, 8-week-old outbred ICR male mice received 8 weeks of drinking water containing a broad range of BPS doses [0.001, 1.0, or 100 μg/kg body weight (bw)/day, BPS1-3] or vehicle control. Mice were sacrificed and testicular tissue taken for histological analysis and protein identification by nano-liquid chromatography/mass spectrometry (MS) and sperm collected for immunodetection of acetylated lysine and phosphorylated tyrosine followed by protein characterisation using matrix-assisted laser desorption ionisation time-of-flight MS (MALDI-TOF MS). RESULTS: The results indicate that compared to vehicle, 100 μg/kg/day exposure (BPS3) leads to 1) significant histopathology in testicular tissue; and, 2) higher levels of the histone protein γH2AX, a reliable marker of DNA damage. There were fewer mature spermatozoa in the germ layer in the experimental group treated with 1 μg/kg bw (BPS2). Finally, western blot and MALDI-TOF MS studies showed significant alterations in the sperm acetylome and phosphorylome in mice treated with the lowest exposure (0.001 μg/kg/day; BPS1), although the dose is several times lower than what has been published so far. CONCLUSIONS: In summary, this range of qualitative and quantitative findings in young male mice raise the possibility that very low doses of BPS may impair mammalian reproduction through epigenetic modifications of sperm proteins.
- MeSH
- acetylace účinky léků MeSH
- endokrinní disruptory farmakologie MeSH
- epigeneze genetická MeSH
- fenoly farmakologie MeSH
- fosforylace účinky léků MeSH
- myši MeSH
- poškození DNA účinky léků MeSH
- posttranslační úpravy proteinů účinky léků MeSH
- spermie účinky léků MeSH
- sulfony farmakologie MeSH
- testis účinky léků patologie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zrání spermie účinky léků MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Cinnamtannin B-1 (CNB-1) is a naturally occurring trimeric A-type proanthocyanidin contained in several plants such as cinnamon (Cinnamomum zeylanicum). It is considered to be a potent antioxidant. The protective effect of CNB-1 against oxidative stress was assessed in red deer epididymal sperm incubated at 37 °C. Cryopreserved sperm from six stags were thawed, pooled and extended to 400 × 106 sperm/ml in BGM (bovine gamete medium). After being aliquoted, the samples were supplemented with different concentrations of CNB-1 (0, 0.1, 1, 10 and 100 μg/mL), with or without induced oxidative stress (100 μM Fe2+/ascorbate). The samples were evaluated after 0, 2 and 4 h of incubation at 37 °C. This experiment was replicated six times. Spermmotility (CASA), viability, mitochondrial membrane potential, acrosomal status, lipoperoxidation (C11 BODIPY 581/591), intracellular reactive oxygen species (ROS) production and DNA status (TUNEL) were assessed. After 4 h of incubation, CNB-1 prevented the deleterious effects of oxidative stress, thus improved sperm progressivity and velocity (P<0.05). Furthermore, 1 and 10 μM CNB-1 improved sperm linearity, even when compared to those samples that had not been subjected to oxidative stress (P<0.05). The greatest concentration, 100 μM, prevented sperm lipoperoxidation and reduced ROS production in samples subjected to oxidative stress.
- MeSH
- antioxidancia farmakologie MeSH
- fragmentace DNA MeSH
- motilita spermií účinky léků MeSH
- oxidační stres účinky léků MeSH
- peroxidace lipidů MeSH
- proantokyanidiny farmakologie MeSH
- reaktivní formy kyslíku metabolismus MeSH
- spermie účinky léků MeSH
- uchování spermatu veterinární MeSH
- viabilita buněk účinky léků MeSH
- vysoká zvěř * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The aim of this study was to assess the effect of insemination timing on pregnancy rates in red deer (Cervus elaphus) when using sex-sorted sperm samples. Semen was collected by electroejaculation from 8 mature stags and processed to obtain: Conventional samples, following standard freezing procedures for commercial purposes; Control sorted samples, diluted and handled as per sorted samples but without being submitted to the sorter passage; and Y Sex Sorted (YSS) samples. Hinds were synchronized via intravaginal CIDR (Controlled Internal Drug Release) placement and given eCG (Folligon® PMSG Serum Gonadotrophin) on day 12, upon CIDR removal. They were then inseminated with one of each sperm treatment, at the following post-eCG intervals: I_1, 55:01-55:30 h; I_2, 55:31-56:00 h; I_3, 56:01-56:30 h; or, I_4, 56:31-57:00 h. Pregnancy rates were assessed at parturition. Average pregnancy rates were highest (P < 0.05) for Conventional samples (77.6%), but similar between YSS (49.8%) and Control sorted (51.3%) samples. However, when insemination interval was taken into account, pregnancy rates within the YSS group, pregnancy rates were 80 and 83.1% for I_1 and I_2, respectively were obtained. Notably, these rates were similar (P > 0.05) to the average pregnancy rates obtained with Conventional samples (77.6%). As expected, YSS sperm yielded 94% male offspring contrasting with the 57% males obtained with Conventional and Control sorted samples. Our findings support the importance of developing specific insemination timing protocols to improve pregnancy rates when using frozen-thawed sex-sorted sperm. These findings provide the foundation for further investigations in order to determine why the YSS sperm are able to fertilize the oocyte in a shorter period of time than the conventional samples.
- MeSH
- fertilita fyziologie MeSH
- kryoprezervace veterinární MeSH
- předvýběr pohlaví veterinární MeSH
- spermie fyziologie MeSH
- těhotenství MeSH
- uchování spermatu veterinární MeSH
- umělá inseminace veterinární MeSH
- vysoká zvěř fyziologie MeSH
- zmrazování * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Reactive oxygen species (ROS) are fundamental for intracellular signalling. In spermatozoa, they are involved both to apoptosis and to capacitation, and changes in ROS levels can alter the balance between these two processes. Oestrous sheep serum (OSS) is considered an efficient agent for in vitro capacitation of ram spermatozoa. We have explored the effects of OSS on ram sperm physiology, especially on ROS production, during in vitro capacitation. Semen samples from 15 rams were cryopreserved. After thawing, samples were submitted to four treatments: control (CTL), 10% OSS supplementation for in vitro sperm capacitation, caspase inhibitor (INH, Z-VAD-FMK 100 μM) and OSS (10%) plus caspase inhibitor (I + E). Sperm samples were incubated for 30 min at 38.5°C and 5% CO2 and evaluated motility and kinetic parameters by computer-assisted semen analysis (CASA) and viability (propidium iodide), apoptotic-like membrane changes (YO-PRO-1), acrosomal status (PNA-FITC), intracellular calcium (FLUO-3), membrane fluidity (M540) and ROS production (CM-H2 DCFDA) by flow cytometry. OSS induced changes in kinetic parameters compatible with capacitation, with a decrease in the percentage of progressive motility and linearity, and an increase in the amplitude of the lateral displacement of the sperm head (p < .05). Moreover, OSS increased the proportion of M540+ viable spermatozoa, YO-PRO-1+ and acrosome-reacted spermatozoa (p < .05). After incubation, OSS and I+E achieved lower ROS levels (p < .05). Ca(2+) levels did not change with the incubation, but were slightly higher (p < .05) when both OSS and the inhibitor were present. We suggest that OSS may modulate ROS levels, allowing intracellular signalling for capacitation to occur while preventing higher levels that could trigger apoptosis.
- MeSH
- estrus krev fyziologie MeSH
- kapacitace spermií fyziologie MeSH
- kaspasy farmakologie MeSH
- motilita spermií MeSH
- ovce krev fyziologie MeSH
- reaktivní formy kyslíku MeSH
- spermie fyziologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The spermatozoon is the most diverse cell type known and this diversity is considered to reflect differences in sperm function. How the diversity in sperm morphology arose during speciation and what role the different specializations play in sperm function, however, remain incompletely characterized. This work reviews the hypotheses proposed to explain sperm morphological evolution, with a focus on some aspects of sperm morphometric evaluation; the ability of morphometrics to predict sperm cryoresistance and male fertility is also discussed. For this, the evaluation of patterns of change of sperm head morphometry throughout a process, instead of the study of the morphometric characteristics of the sperm head at different stages, allows a better identification of the males with different sperm cryoconservation ability. These new approaches, together with more studies employing a greater number of individuals, are needed to obtain novel results concerning the role of sperm morphometry on sperm function. Future studies should aim at understanding the causes of sperm design diversity and the mechanisms that generate them, giving increased attention to other sperm structures besides the sperm head. The implementation of scientific and technological advances could benefit the simultaneous examination of sperm phenotype and sperm function, demonstrating that sperm morphometry could be a useful tool for sperm assessment.
