133 research outputs found
Effects of Resveratrol on Vitrified Porcine Oocytes
Vitrified MII porcine oocytes are characterized by reduced developmental competence, associated with the activation of the apoptotic pathway. Resveratrol (R), a polyphenolic compound present in several vegetal sources, has been reported to exert, among all its other biological effects, an antiapoptotic one. The aim of this study was to determine the effects of R (2 µM) on the apoptotic status of porcine oocytes vitrified by Cryotop method, evaluating phosphatidylserine (PS) exteriorization and caspases activation. R was added during IVM (A); 2 h postwarming incubation (B); vitrification/warming and 2 h postwarming incubation (C); all previous phases (D). Data on PS exteriorization showed, in each treated group, a significantly higher (P<0.05) percentage of live nonapoptotic oocytes as compared with CTR; moreover, the percentage of live apoptotic oocytes was significantly (P<0.05) lower in all R-treated groups relative to CTR. The results on caspase activation showed a tendency to an increase of viable oocytes with inactive caspases in B, C, and D, while a significant (P<0.05) increase in A compared to CTR was recorded. These data demonstrate that R supplementation in various phases of IVM and vitrification/warming procedure can modulate the apoptotic process, improving the resistance of porcine oocytes to cryopreservation-induced damage
Sex-sorted canine sperm cryopreservation: Limits and procedural considerations
The aim of this study was to define a protocol to store dog sperm before and after sorting
to obtain an insemination dose sufficient to allow the conception by artificial insemination.
Experiment 1 and 2 were performed to evaluate the more appropriate extender for preserving
at room temperature dog sperm before and after sorting. Four extenders were
tested: (1) Tris-fructose-citrate (TFC), (2) Tris-glucose-citrate (TGC), (3) modified Tyrode\u2019s
albumin lactate pyruvate medium (mTALP), and (4) third fraction of the ejaculate (after
centrifugation at 5000 g for 10 minutes; III FRAC). Experiment 3 and 4 were performed to
evaluate the ability of dog semen to withstand sex sorting and freezing/thawing. Modified
Tyrode\u2019s albumin lactate pyruvate medium was the best extender for canine sperm storage
at room temperature (20 C\u201325 C) before (total motility: TFC, 8.3 1.7; TGC, 50.0 11.5;
mTALP, 70.0 0.1; III FRAC, 25.0 1 0.4; P < 0.05) and after sorting (total motility: TFC,
7.3 1.5; TGC, 10.3 1.5; mTALP, 33.3 6.7; III FRAC, 8.7 5.8; P < 0.05), even if at 24-
hour sorted sperm quality was impaired in all extenders tested herein. Sperm quality
decreased after sorting (total motility: control, 92.5 0.9; sorted, 52.9 6.0; P < 0.05) and,
especially, after freezing/thawing (total motility: frozen control, 25.7 4.1; frozen sorted,
2.4 1.2; P < 0.05). In conclusion, mTALP is an appropriate medium for canine sperm
storage before and soon after sorting (hours), but a long storage period of sexed sperm at
room temperature is not adequate. Cryopreservation greatly impaired sperm quality, and
further studies are needed to optimize the freezing protocol for sexed dog sperm
Combined effects of resveratrol and epigallocatechin-3-gallate on post thaw boar sperm and IVF parameters
Frozen-thawed boar semen suffer a fertility decrease that negatively affects its widespread use. In recent years supplementing frozen-thawed boar sperm with different antioxidants gave interesting and promising results; the aim of the present work was to study the effect of supplementing boar sperm thawing medium for 1 h with combination of epigallocatechin-3-gallate (EGCG, 50 ÎĽM) and Resveratrol (R, 2 mM), on boar sperm motility (assessed by CASA), viability, acrosome integrity, mitochondrial function, lipid peroxidation and DNA integrity (assessed by flow cytometry), protein tyrosine phosphorylation (assessed by immunofluorescence) and on in vitro fertilization (IVF). Our results demonstrate that sperm motility is negatively affected by R (alone or associated with EGCG, p < 0.05) in comparison to control and EGCG groups both at 1 h and 4 h; this effect is evident both in average motility parameters and in single cells kinematics, studied by cluster analysis, that showed the presence of a specific cell population with simil-hyperactivated features in R group (p < 0.01). Viability, acrosome integrity, mitochondrial functionality and lipid peroxidation are not influenced by the addition of the antioxidants; finally, DNA integrity is negatively influenced by R (both alone or associated with EGCG) both at 1 h and 4 h incubation (p < 0.05). Finally, tyrosine phosphorylated protein immunolocalization, used as capacitation parameter, is not affected by the different treatments. Penetration rate is strongly enhanced by R, both alone or associated with EGCG (p < 0.05); EGCG increases penetration rate as well but to a lower extent. Our findings demonstrate that the combination of R and EGCG could positively affect frozen-thawed boar sperm fertility in vitro; the effect is evident also in R groups, thus demonstrating that this antioxidant is predominant, and no synergic effect is present. Some insights are needed to understand if, in particular R (that showed the strongest effect) could be profitably used for artificial insemination in vivo, given the detrimental effect of this molecule on both sperm motility and DNA integrity
PCV2 infection in vaccinated conventional gilts inseminated with PCV2b-spiked semen
The present trial investigated the effect of PCV2 vaccination on viremia, virus shedding and viral load in maternal tissues and foetuses of conventional gilts inseminated with PCV2b-spiked semen. Twelve gilts were randomly divided into two groups of six animals each (vaccinated infected, VI; non-vaccinated infected, NVI). Estrus synchronization was followed by artificial insemination (AI) with a single PCV2 negative semen dose supplemented with 0.2 mL of a PCV2b suspension containing 104.4 TCID50/50 \u3bcL (total viral dose: 105 TCID50). Vaginal, nasal and faecal swabs, and blood samples were collected weekly from two days before artificial insemination till the end of the experimental period (55 days post AI; DPAI) and tested by real-time PCR (qPCR) for PCV2; sera were tested for anti- PCV2 antibodies. During necropsy foetal and maternal tissues were collected for qPCR and histopathology. In each of the VI and NVI groups three out of the six gilts were pregnant at 29 DPAI. The VI group showed a significantly lower proportion of PCR-positive swabs: 24.6% VI vs 71.3% NVI. PCV2 clearance was demonstrated by qPCR in lymphoid tissue during the trial in the VI group. Only one foetus was PCV2-positive (in the NVI group) and three amniotic fluids of the NVI group. PCV2 was found in a significantly lower proportion of the placenta of foetuses in the VI group (39%) than the NVI group (77%). The PCV2 vaccine seems to play an active role in reducing virus shedding, tissue viral load and foetoplacental infection
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