Brilliant cresyl blue staining negatively affects mitochondrial functions in porcine oocytes.

The aim of the present study was to examine the effects of brilliant cresyl blue (BCB) staining on mitochondrial functions in porcine oocytes. Cumulus-oocyte complexes (COCs) collected from slaughterhouse-derived porcine ovaries were cultured with (13 µM) or without (0 µM, control) BCB for 60 min. Mitochondrial functions in oocytes were examined immediately after staining or after in vitro maturation. The BCB-stained oocytes produced reactive oxygen species (ROS) at higher levels than control oocytes immediately after staining (2.2-fold, P < 0.001) and after maturation (1.7-fold, P < 0.001). The adenosine triphosphate (ATP) content and mitochondrial membrane potential (MMP) in oocytes were similar for the two groups immediately after staining. However, ATP and relative MMP levels were significantly (P < 0.05) lower in BCB-treated oocytes than in the control (2.18 versus 2.83 pM and 0.82 versus 1.0, respectively). There was no difference in mitochondrial DNA copy number between the two groups after maturation. The ATP content in early developmental stage embryos (3 days after parthenogenetic activation) was lower in the BCB-stained group than that in the control group but the difference was not significant. In conclusion, BCB staining of oocytes at the immature stage compromises mitochondrial functions throughout oocyte maturation, but function is restored during early embryo development.

Anxiolytic-like, stimulant and neuroprotective effects of Ilex paraguariensis extracts in mice.

Yerba-mate (Ilex paraguariensis St. Hil.) is the most used beverage in Latin America with approximately 426 thousand of tons consumed per year. Considering the broad use of this plant, we aimed to investigate the anxiety-like and stimulant activity of both the hydroethanolic (HE) and aqueous (AE) extracts from leaves of I. paraguariensis. Swiss mice were treated with I. paraguariensis HE or AE chronically or acutely, respectively, followed by evaluation in the elevated plus-maze (EPM; anxiety-like paradigm), open field (OF; locomotor activity) or the step-down avoidance task (memory assessment). Following behavioral protocols the brains were collected for evaluation of acetylcholinesterase (AChE) activity ex vivo. Chronic treatment with HE induced an anxiolytic-like effect and increased motor activity besides augmented AChE activity. Additionally, acute treatment with AE prevented the scopolamine-induced memory deficit in the step-down avoidance task. Overall, our results indicate the importance of the I. paraguariensis-induced CNS effects, since it is a widely used nutraceutical. We have reported anxiolytic, stimulant and neuroprotective effects for this plant species. These effects are potentially modulated by the cholinergic system as well as by caffeine.

An MP2 and DFT study of heterocyclic hydrogen complexes CnHmY-HX with n=2, m=4 or 5, Y=O, S or N and X=F or Cl.

We present a theoretical study through MP2 ab initio molecular orbital calculations and B3LYP density functional theory with the 6-311++G(d,p) basis set of the heterocyclic hydrogen complexes, CnHmY-HX, where CnHmY = C2H4O, C2H5N and C2H4S, and X=F or Cl. This study aided in the elucidation the main changes in the structural, electronic and the vibrational properties in isolated species, due the hydrogen complexes formation, CnHmY-HX, revealing systematic tendencies in these chemical systems studied. The complexes has CS symmetry, with the HX subunit lying in the plane perpendicular to that of CYC nuclei of heterocyclic and acting as proton donor in forming a hydrogen bond to the heteroatom, Y. A weak secondary interaction between the CH2 groups of heterocyclics and the X atoms in HX causes a significant nonlinearity of the primary hydrogen bond. The hydrogen bond linearity deviations in these complexes due to secondary interactions are represented by theta angle. The MP2 intermolecular distances of complexes C2H5N-HF, C2H4O-HF and C2H4S-HF correspond the 1.652, 1.671 and 2.164 A, respectively, these results are in excellent agreement with experimental results of 1.700 and 2.193 A found for the last two complexes. In the same way, the MP2 values to theta angle, 14.7, 19.1 and 16.8 degrees, has a better reproduction in the experimental results of 16.5, 21.0 and 16.8 degrees, get to the C2H4O-HCl, C2H4S-HCl and C2H4S-HF complexes, respectively.

Cryopreservation of immature equine oocytes, comparing a solid surface vitrification process with open pulled straws and the use of a synthetic ice blocker.

The objective was to evaluate the effect of three cryopreservation methods on the in vitro maturation (IVM) and membrane integrity (MIn) of immature equine oocytes. An open pulled straw (OPS) method, a novel solid surface vitrification (SSV) process, and the addition of a synthetic ice blocker were evaluated. Compared with the control group (N=269), the OPS (N=159) and the SSV (N=202) cryopreservation methods decreased both IVM (50.9 vs. 13.3 and 9.4%, respectively; P<0.001) and MIn (76.6 vs. 31.1 and 33.7%; P<0.001) of immature equine oocytes. However, inclusion of 0.1% ice blocker in the OPS vitrification process increased the rates of both IVM (30.5%; P<0.01) and MIn (45.8%; P<0.05) of the oocytes (N=59). Including 0.1% ice blocker in the SSV process improved the IVM rate (20.9%; P<0.05), whereas MIn remained compromised in this group (N=67). However, increasing the concentration of the ice blocker (to 1.0%) in the cryopreservation methods did not significantly improve rates of IVM. In conclusion, the addition of a synthetic ice blocker (0.1%) to both cryopreservation processes significantly increased rates of both IVM and MIn of immature equine oocytes cryopreserved by OPS.