203 SUPPLEMENTATION WITH LINOLENIC ACID, L-CARNITINE, ALONE OR ASSOCIATED, DURING IVM RESULTED IN DECREASE OF ROS LEVELS AND APOPTOTIC INDEX OF BOVINE IN VITRO PRODUCED EMBRYOS

2016 ◽  
Vol 28 (2) ◽  
pp. 232
Author(s):  
B. C. S. Leão ◽  
N. A. S. R. Frigoni ◽  
P. C. Dall'Acqua ◽  
M. Ambrogi ◽  
G. Z. Mingoti
Keyword(s):  
Reactive Oxygen Species ◽  
Embryonic Development ◽  
Linolenic Acid ◽  
Lipid Content ◽  
Reactive Oxygen ◽  
Antioxidant Effect ◽  
Apoptotic Index ◽  
Control Group ◽  
Oxygen Species

Supplementation of in vitro maturation (IVM) medium with linolenic acid (ALA) has been used in order to reduce oocyte lipid content and have beneficial effects on maturation and acquisition of competence for embryonic development. Besides the effect of reducing cellular lipid content, l-carnitine (l-car) has an antioxidant effect by reducing the levels of reactive oxygen species (ROS) and protecting cells from apoptosis. However, the association of ALA and l-car has never been tested. This study was conducted to evaluate the effects of supplementation of IVM medium of bovine oocytes with ALA, l-car or the association of both (ALA+l-car) on embryonic development and blastocysts reactive oxygen species (ROS) levels and occurrence of apoptosis. Cumulus-oocyte complexes (n = 2241, in 11 replicates) were matured during 22 h at 38.5°C and 5% CO2 in air, in TCM-199 medium with bicarbonate, hormones and 10% FCS (control group), also supplemented with 100 μM ALA group; or 5 mM l-car (l-car group); or 100 μM ALA associated with 5 mM l-car (ALA+l-car group). After fertilisation (Day 0), zygotes were cultured 7 days in SOF that was supplemented with 0.5% BSA and 2.5% FCS, in 5% CO2 in air at 38.5°C. The cleavage and blastocysts rates were evaluated, respectively, at Days 3 and 7. Blastocysts were stained with 5 mM of H2DCFDA (Molecular Probes, Invitrogen, Carlsbad, CA, USA) and TUNEL (In Situ Cell Death Detection Kit, Roche Applied Science, Boston, MA, USA), to evaluate the ROS levels and the blastomers apoptotic index, respectively. The ROS (n = 115) and TUNEL (n = 102) stained blastocysts were evaluated under an epifluorescence microscope (excitation 495 nm/510–550 nm and emission 404 nm/590 nm), and the ROS levels (expressed as arbitrary fluorescence units) were measured by Q-Capture Pro image software (Q Imaging, Surrey, BC, Canada). The fluorescence intensity values were subtracted from mean values of background in the images. The variables were analysed by ANOVA followed by Tukey’s test (P < 0.05) and data are presented as mean ± s.e.m. There was no effect (P > 0.05) of the supplements during IVM on cleavage and blastocysts rates (%), respectively, for control (81.1 ± 1.8 and 29.0 ± 3.1), ALA (80.5 ± 2.1 and 29.7 ± 2.3), l-car (79.5 ± 2.8 and 29.2 ± 2.3), and ALA+l-car (82.2 ± 1.1 and 30.5 ± 2.0) groups. The oocytes supplementation resulted in a decrease (P < 0.05) in ROS levels for ALA (0.84 ± 0.04), l-car (0.85 ± 0.03) and ALA+l-car (0.82 ± 0.02) groups, compared to the Control (1.00 ± 0.05). Consequently, the percentage of apoptotic blastomeres decreased (P < 0.05) after ALA (6.9 ± 1.0%), l-car (7.5 ± 1.2%) and ALA+l-car (4.6 ± 0.7%) supplementations, unlike to the Control group (12.0 ± 1.2%). In conclusion, the supplementation with ALA, l-car or ALA+l-car during IVM did not affect the blastocyst development, but led to a reduction in ROS levels and in the apoptotic index of such blastocysts. These findings may be due to some antioxidant effect of these supplements in the oocytes and/or the produced embryos. Financial support was through FAPESP (#2012/10084–4 and #2013/07382–6).

scholarly journals Qizhi Jiangtang Jiaonang Improves Insulin Signaling and Reduces Inflammatory Cytokine Secretion and Reactive Oxygen Species Formation in Insulin Resistant HepG2 Cells

2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Xiao-Tian Zhang ◽  
Chun-Jiang Yu ◽  
Jian-Wei Liu ◽  
Yan-Ping Zhang ◽  
Chao Zhang ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Palmitic Acid ◽  
Hepg2 Cells ◽  
Reactive Oxygen ◽  
Glucose Consumption ◽  
Control Group ◽  
High Dose ◽  
Oxygen Species ◽  
Insulin Resistant

We analyzed the effects of a traditional Chinese medicine, Qizhi Jiangtang Jiaonang (QJJ), on insulin resistance (IR) in vitro. After an in vitro model of IR was established by treating human liver cancer cells (HepG2 cells) with palmitic acid, the cells were then treated with various concentrations of QJJ. Treatment with 400 µM palmitic acid for 24 h induced IR in HepG2 cells. The survival rate for HepG2 cells in the IR group was significantly lower than that of the untreated control group (P< 0.001); however, QJJ restored HepG2 cell survival (P< 0.001). As compared with HepG2 cells in the IR group, QJJ at all doses analyzed significantly increased glucose consumption (allP< 0.05). Moreover, treatment with all the QJJ doses significantly reduced the mean intracellular reactive oxygen species levels as compared with the IR group (allP< 0.05). Furthermore, high-dose QJJ reduced both TNF-αand IL-6 levels as compared to the IR group (allP< 0.05). QJJ ameliorated the altered PI3K, GLUT4, and RAGE expression observed with IR. In conclusion, QJJ can improve IR in HepG2 cells, which may be mediated through the IRS-1/PI3K/GLUT4 signaling pathway as well as regulation of NF-κB-mediated inflammation and oxidative stress.

183 ADDITION OF DIPHENYLENEIODONIUM OR DEHYDROEPIANDROSTERONE TO CULTURE MEDIA INHIBITS REACTIVE OXYGEN SPECIES PRODUCTION DURING THE EARLY CLEAVAGE STAGES OF IN VITRO-PRODUCED PORCINE EMBRYOS

2007 ◽  
Vol 19 (1) ◽  
pp. 208
Author(s):  
N. W. K. Karja ◽  
K. Kikuchi ◽  
M. Ozawa ◽  
M. Fahrudin ◽  
T. Somfai ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Nadph Oxidase ◽  
Culture Media ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Reactive Oxygen ◽  
Blastocyst Stage ◽  
Control Group ◽  
Ros Production ◽  
Oxygen Species

Nicotinamide adenine dinucleotide phosphate-oxidase (NADPH oxidase), an enzyme required to catalyze the oxidation of NADPH to NADP during the metabolism of glucose via the pentose phosphate pathway (PPP), was considered as contributing to intracellular reactive oxygen species (ROS) production. Production of superoxide anion and H2O2 via NADPH oxidase has been reported on a rabbit blastocyst surface (Manes and Lai 1995 J. Reprod. Fertil. 104, 69–75). The objective of this study was to examine the effects on in vitro development and intracellular ROS content after the addition of diphenyleneiodonium (DPI), an inhibitor of NADPH oxidase, or dehydroepiandrosterone (DHEA), an inhibitor of glucose-6-phosphate dehydrogenase (G6PDH), to culture medium during the early embryonic development of in vitro-produced (IVP) porcine embryos. To confirm that these inhibitors lead to reduction in NADPH concentration in the embryo and hence likely to be inhibiting the PPP, a brilliant cresyl blue (BCB) test was performed on Day 2 (the day of insemination = Day 0) of culture. Porcine cumulus–oocyte complexes were matured and fertilized in vitro as described previously (Kikuchi et al. 2002 Biol. Reprod. 66, 1033–1041). Prezumptive zygotes were then cultured in NCSU-37 supplemented with 5.5 mM glucose and DPI at concentrations of 0.5 or 1 nM or DHEA at concentrations of 10 or 100 �M (DPI-0.5, DPI-1, DHEA-10 and DHEA-100 groups, respectively) from Day 0 to Day 2 of culture. All of the embryos were cultured subsequently until Day 6 in NCSU-37 supplemented with only 5.5 mM glucose. Data were analyzed by ANOVA. On Day 6, the development to the blastocyst stage of embryos in DPI-0.5, DPI-1, DHEA-10, and DHEA-100 groups were 16.1, 17.6, 16.1, and 19.5%, respectively, which were not significantly different from that of the control group (17.5%) (n d 165 per group, 5 replicates). However, the mean cell number in blastocysts derived from DPI-1, DHEA-10, and DHEA-100 groups (40.8 � 2.3, 39.3 � 1.7, and 42.5 � 2.7, respectively) was significantly higher (P &lt; 0.01) than those in the control (33.4 � 1.6) and DPI-0.5 (32.7 � 1.6) groups. At 20 min after an exposure to BCB, the percentage of BCB+ embryos in DPI-1, DHEA-10, and DHEA-100 groups (73.8, 79.9, and 77.8%, respectively) were significantly higher (P &lt; 0.01) than those in the control and DPI-0.5 groups (42% and 53.9%, respectively) (n = 81-92 per group, 6 replicates), indicating that these two inhibitors effectively induce the reduction of NADPH concentration in the embryos. Moreover, the addition of DPI at 1 nM or DHEA at 10 or 100 �M significantly decreased the H2O2 content of Day 2 embryos as compared with control embryos (n = 48-53 per group, 7 replicates). These results suggest that the addition of either DPI or DHEA to the medium during the first 2 days of culture did not impair the development of the embryos to the blastocyst stage. Decrease of cellular ROS production in Day 2 embryos in this study is interpreted as a result of inhibition of the NADPH oxidase by DPI or of the G6PDH by DHEA.

Reduced levels of intracellular reactive oxygen species and apoptotic status are not correlated with increases in cryotolerance of bovine embryos produced in vitro in the presence of antioxidants

2014 ◽  
Vol 26 (6) ◽  
pp. 797 ◽  
Author(s):  
Nathália A. S. Rocha-Frigoni ◽  
Beatriz C. S. Leão ◽  
Ériklis Nogueira ◽  
Mônica F. Accorsi ◽  
Gisele Z. Mingoti
Keyword(s):  
Reactive Oxygen Species ◽  
Reactive Oxygen ◽  
Intracellular Reactive Oxygen Species ◽  
Control Group ◽  
Bovine Embryo ◽  
Oxygen Species ◽  
Antioxidant Supplementation ◽  
In Vitro Production ◽  
Intracellular Ros

The effects of intracellular (cysteine and β-mercaptoethanol) and extracellular (catalase) antioxidant supplementation at different times during in vitro production (IVM and/or in vitro culture (IVC)) on bovine embryo development, intracellular reactive oxygen species (ROS) levels, apoptosis and re-expansion rates after a vitrification–thawing process were examined. Blastocyst frequencies were not affected by either antioxidant supplementation (40.5%–56.4%) or the timing of supplementation (41.7%–55.4%) compared with control (48.7%; P > 0.05). Similarly, antioxidants and the moment of supplementation did not affect (P > 0.05) the total number of blastomeres (86.2–90.5 and 84.4–90.5, respectively) compared with control (85.7). However, the percentage of apoptotic cells was reduced (P < 0.05) in groups supplemented during IVM (1.7%), IVC (2.0%) or both (1.8%) compared with control (4.3%). Intracellular ROS levels measured in Day 7 blastocysts were reduced (P < 0.05) in all groups (0.60–0.78), with the exception of the group supplemented with β-mercaptoethanol during IVC (0.88), which did not differ (P > 0.05) from that in the control group (1.00). Re-expansion rates were not affected (P > 0.05) by the treatments (50.0%–93.0%). In conclusion, antioxidant supplementation during IVM and/or IVC reduces intracellular ROS and the rate of apoptosis; however, supplementation does not increase embryonic development and survival after vitrification.

Tretinoin-loaded lipid-core nanocapsules decrease reactive oxygen species levels and improve bovine embryonic development during in vitro oocyte maturation

2015 ◽  
Vol 58 ◽  
pp. 131-139 ◽  
Author(s):  
Caroline Gomes Lucas ◽  
Mariana Härter Remião ◽  
Eliza Rossi Komninou ◽  
William Borges Domingues ◽  
Cristina Haas ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Embryonic Development ◽  
Oocyte Maturation ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Lipid Core ◽  
In Vitro Oocyte Maturation

Effect of dibutyryl cyclic adenosine monophosphate on reactive oxygen species and glutathione of porcine oocytes, apoptosis of cumulus cells, and embryonic development

Zygote ◽  
2012 ◽  
Vol 21 (3) ◽  
pp. 305-313 ◽  
Author(s):  
Sang-Hyoun Park ◽  
Il-Jeoung Yu
Keyword(s):  
Reactive Oxygen Species ◽  
Embryonic Development ◽  
Reactive Oxygen ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Cumulus Cells ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Oxygen Species ◽  
Cell Numbers

SummaryThe present study was conducted to investigate the effect of dibutyryl cyclic adenosine monophosphate (dbcAMP) supplemented into porcine maturation medium on reactive oxygen species (ROS) and glutathione (GSH) levels of oocytes, and apoptosis of cumulus cells (CC). In addition, the effect of dbcAMP on embryonic development following in vitro fertilization (IVF) or parthenogenetic activation (PA) was determined. Cumulus–oocyte complexes (COCs) were cultured in 0 mM (control), 0.5 mM, 1 mM, 5 mM, or 10 mM dbcAMP-supplemented medium for 22 h, then for another 22 h without dbcAMP. GSH and ROS levels of oocytes were assessed at 44 h of culture by dichlorohydrofluorescein diacetate or 4-chloromethyl-6,8-difluoro-7-hydroxycoumarin staining, respectively. Additionally, COCs were cultured in 0.5 mM or 1 mM dbcAMP and then fertilized in vitro or activated parthenogenetically. Embryonic development and blastocyst cell numbers and apoptosis levels on day 8 of culture were investigated. CC apoptosis at 44 h of culture and blastocyst apoptosis were assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. GSH levels in the 0.5 mM dbcAMP and control groups were increased (P < 0.05), while levels of oocyte ROS and CC apoptosis in the control, 0.5 mM, and 1 mM dbcAMP groups were significantly lower than the levels in other groups. Cleavage and blastocyst rates, cell numbers, and apoptosis levels were not significantly different in embryos derived by either IVF or PA among the groups, with the exception of significantly increased apoptotic levels in IVF blastocysts produced from oocytes treated with 1 mM dbcAMP. In conclusion, dbcAMP treatment during in vitro maturation (IVM) did not improve embryonic development under our study's parameters compared with control conditions, although 0.5 mM dbcAMP showed significantly higher GSH levels and lower blastocyst apoptotic levels compared with 1 mM dbcAMP.

78 SUPPLEMENTATION WITH CARNOSINE DURING IN VITRO CULTURE IMPROVES THE QUALITY OF IN VITRO-PRODUCED BOVINE EMBRYOS

2017 ◽  
Vol 29 (1) ◽  
pp. 146
Author(s):  
D. Le Bourhis ◽  
M. Verachten ◽  
P. Salvetti ◽  
M. Hochet ◽  
L. Schibler
Keyword(s):  
Reactive Oxygen Species ◽  
Reactive Oxygen ◽  
Control Group ◽  
Hatching Rate ◽  
Bovine Embryo ◽  
Oxygen Species ◽  
Cleavage Rate ◽  
Cell Stage ◽  
Blastocyst Rate

The objective of the present study was to determine the effect of supplementation of culture medium with carnosine (β-alanyl-l-histidine; Sigma, St-Quentin Fallavier, France), a reactive oxygen species scavenger, on in vitro bovine embryo development and survival following cryopreservation. Abattoir-derived bovine oocytes (4 replicates) were in vitro matured and fertilized with frozen-thawed semen of one bull, according to our standard procedures. In Experiment 1, 20 h after IVF, groups of presumptive zygotes were cultured in 30 μL of SOF BSAaa + 1% oestrus cow serum with 0 (control; n = 205) or 5 μg mL−1 of carnosine (n = 209) under humidified air with 5% CO2, 5% O2, and 88% N2. Cleavage rates were determined on Day 2, and the blastocyst rates and grade were assessed on Day 7 according to IETS classification. Day 7 grade 1 expanded blastocysts (n = 25 control and n = 27 carnosine) were frozen in 1.5 M ethylene glycol + 0.1 M sucrose. Embryos were thawed and then cultured for 72 h in SOF-BSAaa + 1% oestrus cow serum for re-expansion and hatching rate assessments at +24 h, +48 h, and +72 h post-thawing. In Experiment 2, presumed zygotes were cultured in SOF BSAaa + 1% oestrus cow serum with 0 (control; n = 48) or 5 μg mL−1 of carnosine (n = 48) in a WOW dish and observed with Time Laps Cinematography (Primo Vision®, VitroLife, Göteborg, Sweden). Images were recorded every 15 min for up to 168 h post-insemination. For embryos that reached the blastocyst stage, mean timing of the first cleavage (C1; 2-cell stage), second cleavage (C2; 4-cell stage), second cleavage to compaction (C3), and blastocoel cavity appearance (B4) were recorded. Chi-square test for Experiment 1 and Student’s t-test for Experiment 2 were used, and differences were considered significant at P < 0.05. In Experiment 1, no differences were observed in cleavage rate, blastocyst rate on Day 7, and grade 1 blastocyst rate between both control and carnosine groups (84.0 ± 4.2 v.85.2 ± 3.8, P = 0.7; 46.9 ± 7.1 v. 45.0 ± 7.5, P = 0.7; 24.1 ± 2.0 v. 24.0 ± 6.5, P = 0.6; respectively). After thawing, the re-expansion at +24 h was not different between groups (74.1 v. 48.0% for carnosine and control groups, respectively; P = 0.06). However, at +48 h and +72 h, the survival rate of carnosine treated blastocysts was significantly higher than that of blastocysts in the control group: 70.4 ± 4.5% v. 40.0 ± 3.8% and 59.3 ± 3.8% v. 24.0 ± 3.6%, respectively. Results from Experiment 2 indicated no difference between control and carnosine groups for C1 (32.1 ± 3.9 v. 33.8 ± 6.1; P = 0.3), C2 (8.2 ± 8.9 v. 8.9 ± 0.9; P = 0.07), and B4 (147.0 ± 9.5 v. 145.4 ± 11.6; P = 0.6), whereas C3 was significantly different within groups: 59.9 ± 9.6 v. 51.8 ± 6.7 (P = 0.008). In conclusion, bovine blastocysts derived from zygotes cultured in the presence of 5 μg mL−1 carnosine possess a significantly faster kinetic from 4-cell stage to compaction and show a higher post-thawing viability. However, further analyses are still needed to clarify the relationship between the reactive oxygen species intracellular levels after carnosine treatment and in vitro bovine embryo quality. This work was supported by FECUND European project (grant agreement number 312097).

Reactive Oxygen Species Might Have Important Roles On Angiogenesis of Endothelial Progenitor Cells Derived From HCB(Human Cord Blood) Which Are Stimulated by VEGF.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1445-1445
Author(s):  
Eun-Sun Yoo ◽  
Yeung-Chul Mun ◽  
Kyoung-Eun Lee ◽  
Eunmi Nam ◽  
Jee-Young Ahn ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Nadph Oxidase ◽  
Progenitor Cells ◽  
Endothelial Progenitor Cells ◽  
Reactive Oxygen ◽  
Tube Formation ◽  
Control Group ◽  
Oxygen Species ◽  
Endothelial Progenitor

Abstract Abstract 1445 Poster Board I-468 Purpose VEGF is a key angiogenic growth factor stimulating proliferation, migration, and tube formation on endothelial cells (ECs), that works through the VEGF receptor type 2 (VEGR2, KDR/Flk1). Reactive oxygen species (ROS) such as superoxide and H2O2 have roles signaling for molecules on angiogenesis. In present study, the aim is to investigate the roles of reactive oxygen species on neovascularization in endothelial progenitor cells. Methods Mononuclear cells isolated from UCB were cultured using EGM-2 medium with VEGF, IGF-1 and FGF or basal medium in presence or absence of VEGF for 7 days. Outgrowing endothelail progenitor cells (Yoo et al, STEM CELLS 21:228-235, 2003) at first week of culture were analyzed ROS production by dichlorofluorescein (DCF) fluorescence by use of 2,7-dichlorodihydro-fluoresceine-diacetate (H2DCF-DA). In order to determine that ROS production might involve in EPC proliferation and migration, we had analyzed the impact of N-acetyl-L-cysteine (NAC), broad spectrum ROS scavenger, and NAD(P)H oxidase inhibitor, diphenylene iodonium (DPI) using the proliferation, in vitro tube formation matrigel assay, migration assay with SDF-1/VEGF. We also analyzed the expression of NOX2-based NADPH oxidase (gp91phox) and activation of ERK2 and Akt (Thr308 and Ser473) using VEGF with or without DPI. Results Intracellular ROS level were increased during endothelial progenitor cell culture and were higher in UCB compared to that of BM and increased by VEGF treatment. Proliferation, in vitro tube formation matrigel assay and migration assay on endothelial progenitor cells using SDF-1/VEGF were decreased with additions of ROS scavenger DPI when compared with that of control group. In western blot data, NOX2-based NADPH oxidase(gp91phox) was increased by VEGF and decreased by addition of DPI. VEGF induced pERK2 expression was also decreased by DPI and that finding was correlated on down-regulation of endothelial cell proliferation by DPI. Activation of Ser473 Akt was found in control group and decreased by VEGF and rebounded by VEGF and DPI. But Thr308 Akt was not activated in our experiments. Conclusions These results suggested that NOX2-based NADPH oxidase(gp91phox)-induced ROS might play important roles on EPCs migration and proliferation by VEGF. Namely, manipulating the level of ROS biochemically may alter the pathogenesis in cardiovascular and in ischemic limb diseases. In results, these data may be useful to develop new therapeutic strategies. Disclosures No relevant conflicts of interest to declare.

247 EFFECTS OF SILDENAFIL OR SNAP SUPPLEMENTATION, OR BOTH, DURING IN VITRO MATURATION ON LIPID AND REACTIVE OXYGEN SPECIES ACCUMULATION IN BOVINE OOCYTES AND EMBRYOS

2015 ◽  
Vol 27 (1) ◽  
pp. 213
Author(s):  
M. Del Collado ◽  
R. C. Botigelli ◽  
K. R. L. Schwarz ◽  
C. Elias ◽  
C. L. V. Leal ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Lipid Accumulation ◽  
Reactive Oxygen ◽  
Epifluorescence Microscopy ◽  
Control Group ◽  
Oxygen Species ◽  
Lipid Quantification ◽  
Development Rates ◽  
Bovine Oocytes

Previous studies have demonstrated that a nitric oxide (NO) donor (S-nitroso-N-acetylpenicillmaine, SNAP) and a phosphodiesterase inhibitor (Sildenafil, SILD) delay the meiotic resumption of oocytes removed from the follicular environment, and therefore could be used to improve the quality of in vitro-matured (IVM) oocytes. However, it has been reported that SILD-treated cells have increased lipid metabolism and that NO supplementation can modulate the oxidative stress. This study aims to determine the effects of SNAP or SILD supplementation, or both, during IVM on embryo developmental rates, on lipid accumulation of IVM oocytes and on reactive oxygen species (ROS) and lipid accumulation of embryos derived from IVM oocytes. Bovine oocytes were cultured in TCM199 containing 1.0 μg mL–1 of FSH, 50 μg mL–1 of hCG, 1.0 μg mL–1 of oestradiol, 0.2 mM pyruvate, 83.4 μg mL–1 of amikacin, 10% FBS (control group; GCONT), supplemented with 10 µM SILD (GSILD), 0.1 µM SNAP (GSNAP) or both (GS+S). After 24 h of IVM, matured oocytes were assessed for lipid quantification (approximately 49 per group) or used for in vitro embryo production (IVP; approximately 340 oocytes per group). For lipid quantification, denuded oocytes were fixed with 5% triton in 4% paraformaldehyde (PFA) for 30 min and stained with 1 ng mL–1 of Nile Red for 30 min. Embryo lipid analyses (approximately 55 per group) were performed as described for oocytes. For ROS assessment (approximately 58 per group), IVP embryos were stained with 10 µM of H2DFFDA for 1 h and fixed for 30 min in 4% PFA. Stained oocyte and embryo assessments were performed on epifluorescence microscopy, and captured images were analysed on ImageJ (NIH, Bethesda, MD, USA) to quantify the fluorescence intensity (f.i). Statistical analyses were performed with data from 3 replicates for oocytes and 4 for embryos: statistical differences were assessed for lipid and ROS quantity and development rates by split-plot ANOVA. Variables considered in the model were SNAP (presence/absence) and SILD (presence/absence). Means were compared by Student's t at P < 0.05. Regarding oocyte lipid accumulation, groups with SILD (GSILD and GS+S) presented higher lipid quantity (f.i: 52.11 and 47.24, respectively) compared with GCONT and GSNAP (f.i: 38.86 and 41.86, respectively). Supplementation during IVM did not affect development rates (cleavage of 88.1, 88.2, 88.8, and 89.5% and blastocyst rates of 41.2, 38.6, 40, and 41.2% for GCONT, GSNAP, GSILD, and GS+S, respectively). Regarding embryo lipid quantity, similar to oocyte results, SILD groups (GSILD and GS+S) presented higher lipid accumulation (f.i: 68.9 and 68.5, respectively) compared with GCONT (f.i: 55.8) and GSNAP (f.i: 58.9). Considering embryo ROS quantity, GCONT (f.i: 35.9) and GS+S (f.i: 34.2) had the highest levels; however, GS+S did not differ from GSNAP (f.i: 32.85), which was similar to GSILD (f.i: 30.4). In conclusion, SILD had a negative effect on lipid accumulation, which could be due to increased lipid synthesis without increasing lipid oxidation because no increase of embryo ROS levels was observed.

90 INTRACELLULAR REACTIVE OXYGEN SPECIES IN BOVINE EMBRYOS CULTURED IN VITRO WITH CATALASE UNDER VARIOUS OXYGEN TENSIONS

2012 ◽  
Vol 24 (1) ◽  
pp. 157 ◽  
Author(s):  
N. A. S. Rocha ◽  
B. C. S. Leão ◽  
M. F. Accorsi ◽  
G. Z. Mingoti
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Embryonic Development ◽  
Embryo Development ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Bovine Embryos ◽  
Intracellular Ros ◽  
Oxygen Tensions

The production of reactive oxygen species (ROS), such as superoxide anion (O2–), hydroxyl radical (OH–) hydrogen peroxide (H2O2) and organic peroxides, is a normal process that occurs in the cellular mitochondrial respiratory chain. The high oxygen tension in in vitro culture (IVC) conditions is believed to induce oxidative stress, as a result of increase in ROS intracellular production, that can be correlated with embryonic developmental failure. Supplementation with antioxidants during IVC appears to increase the resistance of bovine embryos to the oxidative stress and consequently improve embryo development. The aim of this study was to evaluate the effects of antioxidant (catalase) and oxygen tensions during IVC on the embryonic development and quantification of intracellular ROS. Cumulus–oocyte complexes (COC; n = 337) were in vitro matured (IVM) in TCM-199 supplemented with 0.2 mM pyruvate, 25 mM sodium bicarbonate, 75 μg mL–1 gentamicin, 10% FCS and hormones for 24 h at 38.5°C and 5% CO2 in air. Then they were fertilized and the presumptive zygotes were cultured in SOFaa medium without (control) or with 100 UI catalase (CAT) for 7 days at 38.5°C in one of 2 types of humified atmosphere: 5% CO2 in air (≈20% O2) or in gaseous mixture (7% O2, 5% CO2 and 88% N2). The cleavage rate was evaluated at 72 hours post-insemination (hpi) and the embryonic development at 168 hpi. At this time, the level of intracellular ROS was measured using the fluorescent probe 6-carboxy-2′,7′-dichlorodihydrofluorescein diacetate (H2DCFDA; Molecular Probes, Invitrogen, Oakville, Canada), at 5 μM (Bain et al. 2011 Reprod. Fertil. Dev. 23, 561–575). Stained embryos were imaged immediately using an inverted microscope and analysed by Q-Capture Pro image software (QImaging, Surrey, BC, Canada). The signal intensity values of embryos were subtracted by the average of backgrounds in the images. Embryo development was analysed by chi-squared test and means of the intensity of fluorescence were compared by ANOVA followed by Tukey's test (P < 0.05). The cleavage rates were 84.04%a (control 20% O2), 77.55%a (CAT 20% O2), 77.03%a (control 7% O2) and 71.83%a (CAT 7% O2). The embryonic development rates were 40.43%a (control 20% O2), 33.67%a (CAT 20% O2), 20.27%b (control 7% O2) and 16.90%b (CAT 7% O2). The fluorescent intensity were 3.9 ± 0.4a (control 20% O2), 1.8 ± 0.2b (CAT 20% O2), 2.7 ± 0.2ab (control 7% O2) and 2.8 ± 0.2ab (CAT 7% O2). Although catalase did not significantly affect blastocyst frequencies (P > 0.05), embryo development was adversely affected by reduced O2 tension (P < 0.05). H2DCFDA staining indicated a significant (P < 0.05) reduction in the levels of intracellular ROS within embryos cultured with catalase under 20% O2 compared with the control group in the same O2 tension. Additionally, a consistent but insignificant reduction in intracellular ROS within embryos cultured under 7% O2 was found. We can conclude that supplementation with catalase to IVC medium at 20% O2 is suitable for lowering intracellular ROS levels in IVP bovine embryos, without lowering the rates of blastocysts production. This finding corroborates with theory that antioxidants are beneficial to embryo quality. Alta Genetics Brazil, Deoxi Biotecnologia.

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