81 VITRIFICATION OF IMMATURE PORCINE CUMULUS - OOCYTE COMPLEXES IN A CHEMICALLY DEFINED SOLUTION

A high concentration of serum supplements has been contained in basic vitrification solutions to protect plasma membranes. The objective of this study was to examine if vitrification of immature porcine oocytes could be achieved successfully in a chemical-defined solution containing 0.6 mg mL–1 hydroxypropyl cellulose (HPC). Cumulus–oocyte complexes (COC) were aspirated from follicles 3 to 6 mm in diameter in abattoir-derived porcine ovaries. The COC or denuded oocytes were vitrified according to a commercial protocol of Cryotop (Kitazato BioPharma Co. Ltd., Shizuoka, Japan) with original solutions or modified ones that had serum supplement replaced with HPC. After vitrification and warming, viabilities of oocytes and cumulus cells were evaluated under a fluorescent microscope after staining with fluorescein diacetate and propidium iodide (Table 1). Statistical analyses of results from 4 replicated trials were performed by ANOVA with a Bonferroni/Dunn post hoc test (significance, P < 0.05). Although viabilities of vitrified/warmed oocytes in all groups were significantly lower (82.7–89.1%) than those of fresh controls (99.5%), there were no significant differences among vitrified groups. When COC were vitrified, viability of cumulus cells (54.3%) in HPC group was not different from that of nonvitrified controls (72.5%) but higher than that in the original solution group (48.1%). In conclusion, these results demonstrate that HPC rather than serum supplement could be a suitable chemically defined supplement for vitrification of immature porcine COC. Table 1.Viabilities of vitrified/warmed porcine oocytes and cumulus cells1

57 TREHALOSE SUPPLEMENTED EXTENDER PRESERVE ACROSOMAL INTEGRITY IN POST-THAW BOAR SPERM

Cryopreservation of boar semen is still considered suboptimal due to lower fertility when compared to fresh semen. The use of glycerol for boar semen cryopreservation may be a reason of low fertility results. Trehalose is a nonreducing disaccharide known to stabilize proteins and biologic membranes during processes such as cryopreservation. The aim of this study was to evaluate the effects of trehalose on boar sperm cryosurvival in an egg-yolk-based extender. The semen samples collected from different individual Berkshires were diluted in egg-yolk-based freezing extender containing glycerol (final concentration 68.5 and 274 mM) or trehalose (50 and 100 mM). Then the samples were cryopreserved using the straw freezing procedure. Frozen sperms were thawed at 39°C in water. Post-thawed sperm were analyzed for motility (under microscope by a conventional method), viability, and acrosome integrity (under fluorescence microscope following LIVE/DEAD or CTC staining, respectively). Statistical analyses of results from 5 replicated trials were performed by ANOVA with a Bonferroni/Dunn post hoc test (significance; P < 0.05). The extender supplemented with 100 mM trehalose exhibited significantly higher acrosomal integrity (41.6%) compared with other extenders (P < 0.05, n = 5; Table 1). The trend of motility and viability was higher in 274 mM glycerol (28.0 and 52.9%) and 100 mM trehalose extenders (23.6 and 53.9%), but those were not significant. These results demonstrate that the presence of trehalose at 100 mM during cryopreservation improves the acrosome integrity of boar sperm, without any reduction in viability and motility, after thawing. Table 1.Effect of glycerol and trehalose on post-thaw boar sperm

265 HYALURONAN SYNTHESIS ABILITY OF PORCINE CUMULUS - OOCYTE COMPLEXES DERIVED FROM SMALL FOLLICLES

The degree of cumulus expansion, an important step in oocyte maturation, of porcine cumulus–oocyte complexes (COC) derived from small follicles (SF: 1 to 2 mm in diameter) is known to be lower than those derived from middle follicles (MF: 3 to 6 mm in diameter). The objective of this study was to compare the abilities of hyaluronan (HA) synthesis of COC from SF and MF. Furthermore, the effect of oestradiol during pre-incubation of COC on proliferation of the cumulus cells was examined. Cumulus–oocyte complexes from SF and MF of porcine ovaries were cultured for in vitro maturation [IVM, in modified porcine oocyte medium (Yoshioka et al. 2008 J. Reprod. Dev. 54, 208–213) supplemented with 50 µM β-mercaptoethanol, 10 IU mL–1 of eCG, 10 IU mL–1 of hCG, and 1 mM dbcAMP for 20 h and then in the fresh medium without those supplements for another 24 h]. Hyaluronan production was quantified at 20 h after the start of IVM with a commercial HA-ELISA kit (20 COC/tube × 4 times). The number of cumulus cells was assessed 0 and 20 h after the start of IVM (50 COC × 4 times). Furthermore, proliferation of cumulus cells was examined after pre-culture of COC (n = 40 COC × 5 times) in modified porcine oocyte medium with various concentrations of oestradiol (0, 0.1, 1, and 10 ng mL–1) for 6 h. Statistical analyses of results from 4 to 5 replicated trials were performed by ANOVA with a Bonferroni-Dunn post-hoc test (significance, P < 0.05). The degree of cumulus expansion of COC from MF (n = 152) was higher than that of COC from SF (n = 156). The incidence of metaphase-II oocytes was significantly lower in COC from SF (n = 133; 48.9%) than in COC from MF (n = 148; 74.7%). The HA content of COC was higher in those from MF (20.8 µg/COC) than in those from SF (10.8 µg/COC), whereas the content per cumulus cell was not different because the numbers of cumulus cells at 0 and 20 h were also higher in COC (n = 200 in each group) from MF (3.0 × 103 and 3.3 × 103 cells, respectively) than from SF (2.0 × 103 and 2.5 × 103 cells, respectively). Cumulus cells proliferated significantly in the presence of oestradiol, regardless of the concentration, during pre-incubation for 6 h (2.5 to 2.8 × 103 cells), as compared with the oestradiol-free controls (2.2 × 103 cells). These results demonstrate that the different abilities of cumulus expansion between COC (n = 200 in each group) from SF and MF may be due to the number of cumulus cells per COC. Pre-incubation in the presence of oestradiol stimulates the proliferation of cumulus cells and may improve the oocyte maturation of COC derived from SF.

224 SILDENAFIL ACCELERATES SPERM PENETRATION OF PORCINE OOCYTES IN A CHEMICALLY DEFINED MEDIUM

Sperm capacitation, a cyclic-adenosine monophosphate-dependent phenomenon, is an important initiation step for penetration into oocytes. In porcine IVF, the use of caffeine, as a nonspecific phosphodiesterase (PDE) inhibitor, is common to accelerate sperm capacitation and penetration. The objective of this study was to examine the effects of PDE inhibitors (cilostamide, rolipram, and sildenafil as PDE type 3-, type 4-, and type 5-specific inhibitors, respectively) on the capacitation of boar sperm and the penetration into porcine oocytes in the absence of caffeine and other capacitation inducers in a chemically defined medium. After washing sperm samples collected from an ejaculated sperm-rich fraction of different individual Berkshires, the sperm were resuspended in capacitation inducer-free (theophylline- and adenosine-free) PGM-tac4 (mPGM-tac) at 5 × 105 cells mL–1. The suspension was cultured in mPGM-tac nonsupplemented or supplemented with 2.5 mM cilostamide, rolipram, or sildenafil for 90 min at 39°C in an atmosphere of 5% CO2 in air, and then the capacitation status was assessed by chlortetracycline fluorescence assay. Other sperm suspensions were used to co-culture with denuded in vitro-matured oocytes in the same medium for 8 h in an atmosphere of 5% CO2 in air and fixed, and sperm penetration was then examined. Statistical analyses of results from 4 replicated trials were performed by ANOVA with a Bonferroni-Dunn post hoc test (significance, P < 0.05). In our result from the chlortetracycline fluorescence assay, although the incidence of intact sperm was significantly reduced in the presence of rolipram (54.3%) and sildenafil (52.7%) as compared with controls (66.7%), there were no differences in capacitated sperm among experimental groups (24.3 to 34.3%). The incidence of acrosome-reacted sperm was higher in the presence of cilostamide (17.3%) than in the others (9.0 to 13.0%). High sperm penetration was observed only in the presence of sildenafil (76.6%) as compared with the control (0%) or the presence of rolipram (4.4%) or cilostamide (1.8%). These results demonstrate that inhibition of PDE type 5, but not PDE type 3 and type 4, significantly accelerates the penetration of boar sperm into the oocytes in a capacitation inducer-free chemically defined medium, whereas inhibition of PDE type 3 may induce an acrosome reaction.

Cytosol and serum concentration of cytokeratin subunit-19 fragment (cyfra-21-1) in breast-cancer

Cytokeratin 19 is a subunit of cytokeratin intermediate filament. CYFRA 21-1 is a new tumor marker using monoclonal antibodies which recognize a fragment of cytokeratin 19. CYFRA 21-1 was measured in cytosol of breast cancer tissues or in sera of patients with breast cancer or benign breast diseases to study the significance of this protein as a tumor marker. The cytosol concentration of CYFRA 21-1 was elevated in cancerous tissue compared to that in adjacent noncancerous tissue, and correlated with the tumor stage or the estrogen receptor status. In the serum, the mean value and positive rate for CYFRA 21-1 (assuming 2.2 ng/ml as the cut-off value) were 0.61 ng/ml (0%) in benign breast diseases, 0.98 ng/ml (6.7%) in stage I/II primary breast cancer, 75.67 ng/ml (60.0%) in stage III/IV primary breast cancer, 45.28 ng/ml (60.0%) in recurrent breast cancer, and 0.64 ng/ml (2.6%) in those with no evidence of recurrence. From the above, we concluded that CYFRA 21-1 could be a tumor marker with high specificity in breast cancer.

Glucose requirement at different developmental stages of in vitro fertilized bovine embryos cultured in semi-defined medium

Three experiments were conducted in which 2-cell bovine embryos were prepared from oocytes, obtained from abattoir ovaries, by in-vitro maturation for 22 to 24 hours, followed by exposure to spermatozoa for 8 hours and culture for 40 hours within the cumulus. The cumulus cells were then removed, and the cleaved embryos were cultured for a further 120 hours or longer, in the presence or absence of glucose, pyruvate and lactate. Very few embryos developed in the complete absence of energy substrates. Lactate and pyruvate, alone or combined, supported development to the 8-cell stage, but pyruvate was required to support development to the morula stage (Experiment 1). When present throughout culture or when added at 48 or 96 hours postinsemination, 5.56 mM glucose was detrimental to development (Experiments 1 and 2). However, when added at 120 hours postinsemination, 5.56 mM glucose improved development to the blastocyst and expanded blastocyst stages, compared with no glucose or 11.12 mM glucose (Experiment 3).

88 COMPARISON BETWEEN STATIC AND DYNAMIC CULTURE RESULTS USING A NOVEL AIR ACTUATION SYSTEM

Mammalian embryos experience not only hormonal stimuli, but also mechanical stimuli (MS), such as shear stress (SS), compression and friction force, in the fallopian tube before nidation. Embryo development performed using previously described in vitro dynamic culture systems is significantly better than that performed using conventional static culture systems. Previously, we found that thawed human embryos showed developmental improvement in the blastocyst stage following a tilting embryo culture system (TECS) culture compared with static culture. However, a disadvantage of the system is the need to use electric devices inside the incubator under humidified conditions. To solve the problem, we developed a dynamic embryo culture system using air actuation and evaluated the applied MS and embryo culture results. We developed an air actuation system with microfluidic channels to apply MS by deforming a 0.1-mm-thick poly(dimethylsiloxane) (PDMS) membrane. The PDMS microfluidic device was placed in a humidified incubator and the mechanical actuator was placed outside the incubator. The embryos' motion in the microfluidic channel was recorded using an inverted microscope and a colour CCD camera with a frame rate of 30 frames s–1. Syringe velocity (VS) was controlled using a software model of the actuation system. The observed maximum velocity of the embryos (VE) and fluid velocity (VF) were calculated by tracking the images of the embryos and the particles in the medium, respectively. The experiments were repeated 3 times. Frozen 2-cell-stage embryos of imprinting control region (ICR) mouse were thawed. 10 to 13 embryos were applied into the microfluidic channel and cultured in ∼200 μL of potassium simplex optimized embryo culture medium covered with mineral oil for 3 days in a humidified environment of 5% CO2 in air at 37°C. The experiments were repeated 5 times. Chi-squared test and Student's t-test were used to determine differences in the blastocyst development rate and in the number of cells in the blastocysts between the groups, respectively. A P-value <0.05 was considered significant. Results: When syringe velocity (VS) was 0.5 mm over a period of seconds, the embryos rotated and did not slide. When VS and fluid velocity (VF) increased, the embryos slipped, did not come in contact with the floor. We conclude that different types and amounts of MS can be applied to the embryos by changing VS. We compared embryo development from the 2-cell stage to the blastocyst stage between static and dynamic cultures in the medium channel. Dynamic culture significantly improved the rate of development to the blastocyst stage (dynamic, 74% (n = 126); static, 62% (n = 118); P < 0.05). The average number of cells (mean ± standard error of the mean) in blastocysts obtained in dynamic and static cultures was 83 ± 3 (n = 54) and 76 ± 3 (n = 51) (P < 0.05), respectively. When the mouse embryos moved at VE of 0.2 mm s–1, there were significant differences in both blastocyst development rate and the average cell number of blastocysts between the 2 groups.

194 IN VITRO MATURATION AND RNA CONTENT AND DISTRIBUTION OF PORCINE OOCYTES DERIVED FROM SMALL AND MEDIUM FOLLICLES AND CLASSIFIED BY BRILLIANT CRESYL BLUE ASSAY

Oocytes collected from the surface of slaughterhouse ovaries clearly have heterogeneous quality. The objective was to characterize a change or difference in RNA distribution and the content of porcine oocytes that were collected from small (SF; 1–2 mm in diameter) and medium follicles (MF; 3–6 mm in diameter) and assessed for glucose-6-phosphate dehydrogenase (G6PD) activity by brilliant cresyl blue (BCB) assay. Following BCB staining, porcine cumulus–oocyte complexes (COC) with dark blue (DB; G6PD-inactive, suggesting good quality) and light blue (LB; G6PD-active, suggesting immaturity) ooplasm were then separately cultured in vitro to evaluate nuclear maturation and analyze the characteristics of the RNA aspect. RNA distributions in cumulus cell mass and ooplasm were labeled with fluorescence, SYTO RNA select green and then examined at different periods of culture for in vitro maturation (IVM; with gonadotropins and dbcAMP for 20 h and then without those for 24 h). Total RNA content of oocytes and cumulus cell mass were measured by using a manufacture's kit (Invitrogen Quant-iT RNA assay kit). Statistical analyses of results from 3 to 5 replicated trials were performed by ANOVA with a Bonferroni/Dunn post-hoc test (significance, P < 0.05). When oocytes were classified by BCB assay, the percentage of oocytes with DB cytoplasm was much higher (P < 0.05) in oocytes from MF (72.5% of 208) compared with those of SF (53.6% of 352). Regardless of the origin of oocytes (SF vs MF), the incidence of mature oocytes following culture was higher in DB than LB (64.0% of 147 and 72.1% of 133 vs 50.9% of 108 and 52.8% of 54, respectively). Twenty hours after the start of IVM, the DB oocytes had a higher proportion of RNA-free zone inside the germinal vesicle compared to the LB oocytes (66.1% of 193 and 26.8% of 159 in MF; 47.9% of 185 and 17.9% of 184 in SF; P < 0.05). When the total content of RNA was examined during IVM, both oocytes from SF and MF contained higher levels of total RNA at the beginning of IVM as compared with 20 and 44 h after the start of IVM, whereas the content (40 denuded oocytes/sample) was higher in oocytes with DB cytoplasm from MF than those from SF (P < 0.05). Regardless of the origin of oocytes from SF and MF, the total content of RNA in oocytes with LB cytoplasm was significantly lower than in oocytes with DB cytoplasm (P < 0.05) before the start of IVM. The total RNA content of cumulus cells (40 COC/sample) before IVM culture was also higher in the cell mass surrounding the DB oocytes than the LB ones and in the cell mass surrounding the oocytes from MF rather than SF (P < 0.05). These results demonstrate a possibility that differences in RNA distribution and content in oocytes, as well as the content in cumulus cells, reflect in the ability of porcine oocytes to mature in vitro.

Effect of the addition of beta-mercaptoethanol to a thawing solution supplemented with caffeine on the function of frozen-thawed boar sperm and on the fertility of sows after artificial insemination

We have reported that artificial insemination (AI) with frozen-thawed boar semen supplemented with caffeine increased the number of uterine sperm by inhibiting the migration of polymorphonuclear leukocytes (PMNs) into the uterine lumen, thereby improving the fertility of gilts and sows. The objective of the present study was to examine the effects of the addition of the antioxidant beta-mercaptoethanol (bME) and caffeine to the thawing solution on the function of frozen-thawed sperm, on the phagocytic activity of PMNs for sperm, and on the fertility of sows after AI. When frozen-thawed sperm were cultured in the presence of 25 or 50 μm bME, sperm capacitation and spontaneous acrosome reactions were inhibited (P < 0.01). There was no effect of bME on phagocytic activity of PMNs for sperm in vitro. When hormonally treated (400 IU of equine chorionic gonadotropin + 200 IU of human chorionic gonadotropin) weaned sows experienced a single intrauterine insemination with frozen-thawed sperm (25 × 10(8) sperm per 50 ml dose) 40 h after subsequent hCG administration, pregnancy and farrowing rates were unaffected by the addition of 50 μm bME (pregnancy rate, 20 vs 21% in controls; farrowing rate, 20 vs 21%; n = 15 and 14, respectively). However, litter size tended to be higher than in the presence of 50 μm bME compared to its absence (10.0 ± 1.0 vs 5.7 ± 1.5, respectively; P < 0.07). Thus, the addition of bME to the thawing solution containing caffeine could be of benefit for improving the function of frozen-thawed sperm without influencing the phagocytic activity of PMNs for sperm. Although there were no statistically significant effects of bME on pregnancy or farrowing rates, the litter size tended to be higher in the sows subjected to a fixed-time single AI treatment with synchronized ovulation.

223 CHANGE IN THE DISTRIBUTION OF RNA IN BOAR SPERM DURING CULTURE IN A CAPACITATION MEDIUM CONTAINING CAFFEINE

Mammalian sperm are known to contain various types of RNA. Recently, translation of RNA to proteins occurring during capacitation was reported to be important for sperm function and fertilization. The objective of this study was to examine the change in the distribution of RNA in boar sperm during culture in a capacitation medium containing caffeine by using fluorescence specifically binding to RNA. The sperm-rich fraction from Berkshire boars (n = 4) was diluted (cells mL–1) with modified Modena solution containing 20% seminal fluid, cooled to 15°C for 4 h, and kept at the same temperature until use. Stored, diluted semen was washed by centrifugation (1500 rpm for 35 min at room temperature) in a Percoll gradient (45/90%). A sperm suspension (concentration 1 × 107 cells mL–1) in modified TCM-199 containing 0.4% BSA and 5 mM caffeine was then prepared and cultured in an atmosphere of 5% CO2 in air at 39°C for 1 or 4 h. Before and after culture, sperm were stained by using SYTO RNA Select Green Fluorescence Cell Stain (Molecular Probes, Eugene, OR) according to the manufacturer’s protocol, and then the mounted specimens were observed and the intensity of fluorescence images was measured under a fluorescence microscope (BIOREVO, Keyence, Osaka, Japan). Viability of sperm was also determined following SYBR-Green–propidium iodide staining under a fluorescence microscope. Statistical analyses were carried out by ANOVA and with a Bonferroni-Dunn post-hoc test (P < 0.05). Although the viability of sperm decreased before (96.7%) and 1 h after the start of culture (79.8%), it did not decline until 4 h after the start of culture (80.9%). Before culture, fluorescence indicating the presence of RNA was observed at the head, especially the postacrosomal region and the midpiece region of the sperm. The intensity of fluorescence changed during culture. The fluorescence intensity of RNA at the sperm head region was higher (P < 0.01) at 1 h of culture (36.11 × 104) than before culture (30.50 × 104) and at 4 h of culture (28.60 × 104). The intensity of RNA at the midpiece region was higher (P < 0.01) at 1 h (11.42 × 104) and was lower (P < 0.01) at 4 h of culture (4.93 × 104) than before culture (8.45 × 104). From these results, we concluded that the distribution and content of RNA changes drastically during culture in a capacitation medium containing caffeine. Additional study of the kinetics of sperm RNA during capacitation is ongoing to further understand the post-transcriptional regulation.

14 EFFECT OF PORCINE SEMINAL PLASMA AND EGG YOLK ON CHEMOTAXIS AND PHAGOCYTOSIS OF NEUTROPHILS DERIVED FROM PERIPHERAL BLOOD OF PIGS AND COWS

The aim of this study was to determine the effects of porcine seminal plasma (0 to 20%, vol/vol) and egg yolk (0 to 20%, vol/vol) on chemotaxis and phagocytosis of porcine and bovine polymorphonuclear neutrophil (PMN) in vitro. Chemotaxis was determined using a blind well chamber. The phagocytosis assay was performed according to (Matthijs et al. 2000 J. Reprod. Fertil. 120, 265–273) with modification in pigs and cows. The serum-stimulated chemotactic activity of PMN (porcine, 1126.1 ± 14.4 cells/mm2 and bovine, 1067.1 ± 9.5 cells/mm2) was reduced (n = 4; P < 0.05) in the presence of 5% pig seminal plasma (pig, 1009.3 ± 12.4 cells/mm2 and cow, 800.0 ± 17.3 cells/mm2). More than 5% (vol/vol) of pig seminal plasma significantly decreased the chemotaxis of PMN in pigs and cows. The presence of 1% and higher concentrations (vol/vol) of seminal plasma reduced (n = 4; P < 0.05) leukocyte phagocytosis in pigs (37.1 ± 1.4 v. 41.7 ± 1.0%) and cows (36.4 ± 1.6 v. 42.1 ± 1.1%) compared with controls, and higher concentrations decreased the phagocytotic activity of PMNs in a concentration-dependent manner (n = 4; P < 0.05). Interestingly, 20% egg yolk increased (n = 4; P < 0.05) chemotaxis of PMN in pigs (953.5 ± 11.6 v. 789.9 ± 13.1 cells/mm2) and cow (988.6 ± 14.6 v. 790.4 ± 19.4 cells/mm2) compared with controls. The egg yolk increased (n = 4; P < 0.05) phagocytosis ability of porcine PMN (35.3 ± 1.6 v. 24.9 ± 2.4%) compared with the control. However, 20% egg yolk did not affect phagocytotic ability of PMN in cows (15.1 ± 1.6 v. 15.8 ± 1.0%). These results demonstrated that porcine seminal plasma, regardless of whether the species was pigs or cows, reduced chemotactic and phagocytotic activities of PMN. However, egg yolk significantly increased chemotactic activity of PMN in pigs and cows, while the egg yolk increased phagocytosis of PMN in pigs, but not in cows. In addition, porcine seminal plasma and caffeine reduced the egg yolk-induced increase in chemotactic and phagocytotic activities of PMN in both species. Supported by JSPS Grants-in-Aid (B20380154).

245 ANALYSIS OF CORTICAL GRANULE EXUDATE OBTAINED BY CHEMICAL OOCYTE ACTIVATION IN PIGS

Cortical granules (CG) are clue organelles in the mammalian oocyte because once released, their content modifies the zona pellucida (ZP) and oolema, thus preventing polyspermy. However, research on putative CG proteins has progressed slowly because of the picogram amount of proteins contained in CG. Isolation and identification of CG contents in porcine oocytes would help to elucidate the molecular mechanism involved in blocking polyspermic fertilization. Our objective was to study the contents of CG from in vitro-matured (IVM) porcine oocytes, and to achieve this objective, CG exudate was collected after its release from chemically activated oocytes. Oocytes were subjected to IVM in porcine oocyte medium supplemented with 50 μM β-mercaptoethanol for 44 h. After the IVM period, the ZP was removed by protease treatment (0.5% pronase in PBS), and the ZP-free oocytes were activated with calcium ionophore A23187 (6.5 μM, 2 min) in a medium consisting of 114.06 mM NaCl, 3.20 mM KCl, 0.50 mM MgCl2·6H2O, 10.00 mM sodium lactate, 0.35 mM NaH2PO4, 5.00 mM glucose, 25.07 mM NaHCO3, and 8.00 mM calcium lactate·5H2O. After activation, oocytes were transferred to fresh medium without calcium ionophore and kept for 30 min to allow release of the CG content. After this time, medium containing the CG exudate was collected, as well as the activated oocytes, and both samples were stored at –80°C until analysis. Samples were thawed and the CG proteins were concentrated by centrifugation in 10-kDa centrifugal devices (Microcon, Millipore, Billerica, MA) following the manufacturer’s instructions. The CG exudates from activated oocytes (n = 300) and activated oocytes (n = 125) were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. In brief, 4% stacking and 12% separating gel was used and run using 25 mM Tris–0.2 M glycine buffer, pH 8.6, containing 0.1% SDS for 1.5 h at 150 V and room temperature. After electrophoresis, the gel was silver stained. Thirteen strong bands were identified in the CG exudate lane, with an approximate molecular mass from approximately 45 to 105 kDa. However, the lane for activated oocytes showed faint protein bands. The presence of well-defined bands in the CG exudate lane might correspond to different CG-derived proteins. These preliminary results show a new approach for studying CG content. Further proteomic analysis of the bands will help to describe specific proteins contained in these organelles, shedding light on the role of the cortical reaction in pigs. Supported by MEC and FEDER (AGL2009-12512-C02-01) and Okayama Universit R. R. was granted funding by JSPS (Ref. S-09210).

263 REGULATION OF SEVERAL TRANSCRIPTS DURING IN VITRO MATURATION IN PORCINE OOCYTES COLLECTED FROM DIFFERENT SIZE FOLLICLES

Oocyte-specific transcripts play important roles in oocyte maturation, fertilization, and early embryonic development. Currently, oocytes from medium-size follicles have been used for different assisted reproductive techniques after in vitro maturation (IVM). The aim of this study was to compare the mRNA expression level in porcine oocytes collected from medium (3–6 mm) and small (<2 mm) size follicles. Genes were selected based on their described maternal effect (NALP9, HSF1), their identification as markers of oocyte maturation (AURK-A, AURK-B, MOS, and C-mos), their involvement in fertilization (ZP3, ZP4), and anti-apoptotic effect (Bcl-2). All transcripts were studied in oocytes just after collection [germinal vesicle (GV) stage] and after in vitro maturation (IVM; metaphase II stage). To ensure nuclear stage of immature oocytes, oocytes were mechanically denuded just after collection, centrifuged (10 000 rpm, 5 min, RT), and observed under the microscope (60×). Those oocytes with clear nucleolus and evident nuclear membrane were selected and stored (n = 10) until study. For metaphase II oocytes, only those exhibiting the extrusion of first polar body after IVM (n = 10) were selected. Total RNA was extracted from the pool of 10 immature and mature oocytes. One picogram of luciferase mRNA per oocyte was added as an exogenous standard. Total RNA was extracted from oocytes and cDNA was obtained and used as a template for quantitative PCR to analyse the level of different transcripts. The whole process was replicated 4 times. Data were normalized to the luciferase RNA and analysed by one-way ANOVA with maturational stage (GV or metaphase II) and follicle size (small or medium) as fixed factors. Results show that all transcripts were significantly decreased during IVM (P < 0.05). Therefore, after IVM, NALP9, AURK-A, MOS, C-mos, ZP3, ZP4, and Bcl-2 transcripts were significantly reduced in matured oocytes compared with immature ones irrespective of follicle diameter. Transcripts of AURKAB and HSF1 decreased after IVM in oocytes from medium follicles or small follicles, respectively. A significant effect of follicular size was only detected in MOS transcripts in GV-stage oocytes because those collected from middle follicles had a higher amount than the ones from small follicles (Table 1). These results suggest that the variations in the maternal store of RNA during IVM are not related with follicle diameter for the studied genes. Further investigations are necessary to determinate the developmental competence of oocytes that came from different types of follicles (small and medium follicles). Table 1.Variation of transcripts during in vitro maturation in porcine oocytes collected from small and medium follicles This study was supported by Okayama University. R. Romar was given a grant by JSPS (Ref. S-09210).

216 PRONUCLEAR FORMATION AND DEVELOPMENTAL COMPETENCE OF MATURE PORCINE OOCYTES DERIVED FROM SMALL- AND MEDIUM-SIZED FOLLICLES

The maturation rate of oocytes derived from small follicles (SF) is known to be lower than that of oocytes from medium follicles (MF). The objective of this study was to assess the fertilizability and developmental competence of mature SF oocytes that were selected by the presence of the first polar body. Cumulus–oocyte complexes (COC) were aspirated from SF (1 to 2 mm in diameter) or MF (3 to 6 mm in diameter) of prepuberal ovaries. The COC were cultured in modified porcine oocyte medium supplemented with gonadotropins and dibutyryl cAMP for the first 20-h period and then in gonadotropin-free and dibutyryl cAMP-free porcine oocyte medium for another 24 h. Following IVM culture, mature oocytes with the first polar body were selected under a stereomicroscope, co-incubated with spermatozoa in a drop of modified TCM-199 containing 0.4% BSA and 5 mM caffeine for 6 h, and then incubated in porcine zygote medium-5 for 7 days. Sperm penetration, cleavage, and early development of the oocytes were examined before culture in porcine zygote medium-5 on Days 2 and 7 of culture. To analyse the fertilizability and developmental competence of oocytes from the SF and MF groups, sperm penetration, pronuclear formation, cleavage, blastocyst formation, and mean cell number in a blastocyst (as determined by fluorescence observation following Hoechst 33342 staining) were examined. Statistical analysis was performed by ANOVA with a Bonferroni-Dunn post-hoc test (P < 0.05). The percentages of oocytes in which the first polar body could be observed were 51.0 ± 4.5% and 78.5 ± 2.8% for SF- and MF-oocytes, respectively, whereas the maturation rates were 83.8 ± 4.0% and 62.8 ± 4.4% following fixation and staining. When only mature oocytes were co-cultured with sperm for 6 and 9 h, sperm penetration, monospermic penetration, and pronuclear formation were not different (P > 0.33) between mature SF- and MF-oocytes. Although there was no difference in cleavage rates between the mature SF- and MF-oocyte groups, blastocyst formation rate and mean cell number in the blastocyst were higher in mature MF-oocytes (31.0 ± 3.6% and 38.7 ± 1.9 cells, respectively) than in mature SF-oocytes (14.7 ± 3.2% and 31.2 ± 2.0 cells). From these results, we conclude that mature oocytes derived from SF have a similar fertilizability when compared with mature MF-oocytes, but the developmental competence to the blastocyst stage following IVF is significantly lower in mature SF-oocytes than in mature MF-oocytes.

272 INTRACELLULAR NITRIC OXIDE LEVEL OF PORCINE OOCYTES IS NEGATIVELY CORRELATED WITH OOCYTE MATURATION RATE AND CUMULUS EXPANSION INDEX IN A CHEMICALLY DEFINED MEDIUM

Nitric oxide (NO) has been known to inhibit nuclear maturation in cumulus–enclosed oocytes in rodents. The objective of this study was to examine if meiotic stimulators, such as dibutyryl cAMP and epidermal growth factor (EGF), influence intracellular NO level of oocytes and if the level is correlated with oocyte maturation rate and cumulus expansion in a chemically defined medium. Oocyte–cumulus complexes (OCC) were aspirated from mid-size follicles (3–6 mm in diameter) of prepuberal porcine ovaries. The OCC were cultured in modified porcine oocyte medium with various supplements – gonadotropins plus dibutyryl cAMP (Gn + cAMP), EGF plus dibutyryl cAMP (EGF + cAMP), dibutyryl cAMP alone (cAMP), EGF alone (EGF), and non-supplements (none) – for a first 20-h period and then in fresh porcine oocyte medium (without those supplements) for another 24 h in an atmosphere of 5% CO2 in air at 39°C. Following in vitro maturation culture, OCC were assessed for the degree of cumulus expansion (scored from 0 as cumulus free to 5 as full expansion) and then additionally cultured with DAF2-DA, an indicator of NO, for an additional 1-h period in the same condition. The oocytes were denuded with 0.1% hyaluronidase, and the intensity of fluorescence was measured. The oocytes were also fixed, stained with acetic orcein, and observed for meiotic stage. Statistical analysis was performed by ANOVA with a Bonferroni-Dunn post hoc test (significance, P < 0.05). Maturation rates and cumulus expansion indexes were significantly affected by various supplement conditions (Table 1). The intensity of fluorescence showing intracellular NO level was also different among experimental groups (Table 1). A negative correlation was found between intracellular NO intensity and maturation rate (r2 = 0.71) or cumulus expansion index (r2 = 0.70). From these results, we conclude that there is a synergistic effect of cAMP and EGF on cumulus expansion and oocyte maturation and the reduction of oocyte NO levels in a chemically defined medium. Furthermore, a reduction of oocyte NO level seems to be included in the induction of cumulus expansion and oocyte maturation. Table 1.Effects of supplements on nuclear maturation, cumulus expansion, and intracellular NO level of porcine oocytes1

24 EFFECT OF CULTURE OF SEMEN IN A LOW PRESSURE CONDITION AT ROOM TEMPERATURE ON VIABILITY AND CAPACITATION STATUS OF BOAR SPERM

Sperm are affected by physical conditions, such as centrifugation and temperature. The objective of this study was to examine the effect of a low atmospheric pressure on viability and capacitation status of boar sperm during semen preservation at room temperature. Sperm-rich fraction from Berkshire boars was diluted at cells mL–1 with modified Modena containing 20% seminal fluid after washing with centrifugation (300 × g for 35 min at room temperature) in a Percoll gradient (45%/90%). The sperm suspension was stored at a pressure of 0.5 or 1.0 atmospheres in the dark at room temperature (25°C). Following storage for 4 h or 4 days, the semen samples were analysed for viability, intracellular calcium level, and acrosome status of the sperm. Viability and intracellular calcium level of sperm were assessed by flow cytometry following staining with SYBR-Green/PI and Furo-3/PL, respectively. Sperm status associated with capacitation and acrosome reaction was analysed by CTC-assay under fluorescence microscope. Statistical analyses of data from 4 or 5 replicated trials were carried out by ANOVA and with a Bonferroni-Dunn post hoc test (significance, P < 0.05). Viability of sperm was not different (P = 0.50) between 2 pressures (0.5 and 1.0 atm) 4 h and 4 days after the start of storage (94.6% v. 95.6% and 92.7% v. 94.3%, respectively). Although the percentage of live sperm with high intracellular calcium levels drastically increased (P < 0.01) 4 days after the start of storage (20.2% v. 23.4%) compared with 4 h of storage (5.5% v. 4.9%), there were no differences between sperm stored in 0.5 and 1.0 atm at 4 h (P = 0.80) and 4 days of storage (P = 0.40). After 4 h of storage, there were no differences in the percentage of intact (93.3% v. 94.7%), capacitated (5.5% v. 4.3%), and acrosome-reacted sperm (1.5% v. 1.5%) between sperm stored in 0.5 and 1.0 atm. After 4 days of storage, however, the percentage of intact sperm decreased when the sperm suspension was cultured in 0.5 atm (71.8%) compared with 1.0 atm (88.5%), and the incidence of capacitated sperm increased (14.3% v. 7.8%, respectively), whereas there was no difference in the acrosome-reacted cells. These results demonstrate that the status of sperm associated capacitation is stimulated in a low atmospheric pressure without any effects of the viability of sperm, during storage for 4 days.

Cancer cell-derived IL-1α promotes HGF secretion by stromal cells and enhances metastatic potential in pancreatic cancer cells

BACKGROUND AND OBJECTIVES

Interleukin (IL)-1α and hepatocyte growth factor (HGF) play an important role in pancreatic cancer proliferation, angiogenesis, and invasiveness. The aim of this study was to investigate the cooperative role of HGF and IL-1α in metastatic processes promoted by interactions between pancreatic cancer cells and stromal cells.

METHODS

Expression of IL-1α and HGF mRNA and protein was determined by RT-PCR and ELISA. The effect of HGF on metastatic potential was evaluated by proliferation, invasion, and angiogenesis assays using an in vitro system consisting of co-cultured tumor cells and stromal cells.

RESULTS

IL-1α expression was closely correlated with metastatic potential, and cancer cell-derived IL-1α significantly promoted HGF expression by fibroblasts (P < 0.01). HGF not only enhanced the invasiveness and proliferation of pancreatic cancer cells, but also enhanced migration and proliferation of human umbilical vein endothelial cells (HUVECs). HGF significantly enhanced HUVEC tube formation (P < 0.01). Furthermore, the high liver-metastatic pancreatic cancer cell line (BxPC-3), which secretes IL-1α, significantly enhanced HUVEC tube formation compared with the low liver-metastatic cell line (Capan-2), which does not produce IL-1α (P < 0.01).

CONCLUSION

Autocrine IL-1α and paracrine HGF co-enhance the metastatic potential of pancreatic cancer cells via both IL-1α and HGF signaling pathways.

Strategies for gastric cancer in the modern era

Gastric cancer is one of the most common neoplasms in Japan, and it is also the second leading cause of cancer-related deaths worldwide. Nowadays, infection with Helicobacter pylori (H. pylori) is a known risk factor for the development of gastric cancer. Therefore, gastric cancer should be considered as an infectious disease, and in fact, prophylactic eradication of H. pylori may prevent the development of metachronous gastric carcinoma. Before the role of H. pylori was understood, a different approach was used. Recently even after the cancer has developed, some newer therapeutic approaches have been pursued. These newer treatments have been summarized as “minimally invasive therapies” and use endoscopic or laparoscopic techniques. In addition, robotic approaches are being developed that seem to hold a great potential to change the surgical approach. Since basic understanding and treatment of the disease have both changed significantly over the last decade, we present a review of current advances in gastric cancer research and therapy.

Proteasome inhibitor MG132 inhibits angiogenesis in pancreatic cancer by blocking NF-kappaB activity

Since angiogenesis enables solid tumors, including pancreatic cancer (PaCa), to grow and metastasize, the development of anti-angiogenic agents is currently one of the urgent issues. Proteasome inhibitors are well known for inhibiting nuclear factor-kappa B (NF-kappaB) activity in various cancer cells, but little is known about their biologic mechanisms against angiogenesis in PaCa. We divided human PaCa cell lines into high-angiogenic (BxPC-3 and SW 1990) and low-angiogenic (MIA PaCa-2 and Capan-2) groups. The high-angiogenic PaCa cell lines constitutively expressed high NF-kappaB activity and produced high levels of vascular endothelial growth factor (VEGF) and interleukin 8 (IL-8). The conditioned media from BxPC-3 significantly enhanced both proliferation of and tube formation by human umbilical vein endothelial cells (HUVECs) and these enhancements were significantly inhibited by the proteasome inhibitor MG132 treatment. Collectively, MG132 blocked PaCa-derived VEGF and IL-8 production through inhibition of NF-kappaB activity. Thus, proteasome inhibitors may prove beneficial as anti-angiogenic therapy for PaCa. Our studies show that MG132, a proteasome inhibitor, significantly blocked pancreatic-cancer-associated angiogenesis through inhibition of NF-kappaB and NF-kappaB-dependent proangiogenic gene products VEGF and IL-8.

348 CO-CULTURE OF PORCINE OOCYTES - CUMULUS COMPLEXES DERIVED FROM SMALL FOLLICLE WITH CUMULUS-CELL MASSES FROM MIDDLE FOLLICLE IMPROVES MEIOTIC MATURATION OF THE OOCYTES

It is known that maturation rate of oocytes derived from small follicles (SF) is lower than that of oocytes from middle follicles (MF). Since it has been reported that cumulus cells have important role during oocytes maturation, the ability of SF oocytes to complete the meiotic maturation may be affected by additional cumulus-cell mass. The present study was undertaken to examine the effects of co-culture of oocyte-cumulus complexes (OCCs) derived from SF with additional cumulus-cell masses on in vitro maturation and developmental competence of the oocytes. OCCs were aspirated from small (SF; 1-2 mm in diameter) or middle follicles (MF; 3-6 mm in diameter) of prepuberal ovaries. OCCs were cultured in porcine oocyte medium (POM; Research Institute for the Functional Peptide, Yamagata, Japan) supplemented with gonadotropins and dbcAMP for a first 20-h period and then in gonadotropin-free and dbcAMP-free POM for another 24 h. Culture medium was collected after the first 20-h culture and the end of IVM, and analyzed for the protein profiles. Following IVM, some oocytes were co-incubated with spermatozoa in a drop of modified Medium199 containing 0.4% BSA and 5 mM caffeine for 8 h and then incubated in PZM5 (Research Institute for the Functional Peptide, Yamagata, Japan) for 6 days. Sperm penetration, cleavage, and the early development of the oocytes were examined before culture in PZM5 or Day 2 and Day 6 of culture, respectively. OCCs derived from SF were co-cultured with cumulus-cell masses derived from SF or MF during IVM (SFO-SFC and SFO-MFC groups, respectively). Some OCCs derived from SF or MF were cultured for IVM without additional cumulus-cell masses (SFO and MFO, respectively). After culture, meiotic maturation of the oocytes was examined. To analyze the developmental competence of oocytes of SF, MF, and SFO-MFC groups, sperm penetration, pronuclear formation, cleavage, and blastocyst formation were examined. Protein profiles in the IVM media were examined by 10% SDS-PAGE. Statistical analysis was performed by ANOVA with a Bonferroni-Dunn post hoc test (significance, P ≤ 0.05). After culture for IVM, the diameters of SFO and SFO-MFC were not different from that of MFO (113.3-114.5 μm). The maturation rate of SFO-MFC oocytes (75.5 ± 6.2%) was higher than SFO (52.2 ± 2.8%) and comparable with the rate of MFO oocytes (83.2 ± 6.3%), while there was not significant difference between the mature rate of SFO+SFC oocytes (63.6 ± 4.0%) and SFO oocytes. There were no significant differences between groups in sperm penetration, pronuclear formation, and cleavage. Blastocyst formation of SF oocytes was not improved by co-culture with MF cumulus-cell masses. Certain band was detected only in MF medium of collected at 20 h (24.5 kD). From these results, we conclude that secretions from cumulus-cell masses derived from MF well improve the meiotic progress of oocytes derived from SF, but not the early development following IVF.

IL-1alpha secreted by colon cancer cells enhances angiogenesis: the relationship between IL-1alpha release and tumor cells' potential for liver metastasis

BACKGROUND AND OBJECTIVES

Interleukin (IL)-1alpha plays an important role in colon cancer progression and angiogenesis. We here asked whether IL-1alpha derived from cancer cells modulates vascular endothelial cell growth, migration and tubule formation.

METHODS

The existence of IL-1alpha mRNA and protein in colon cancer cell lines (WiDr, HT-29, Caco-2, COLO 320) were investigated with RT-PCR and ELISA. Proliferation and invasion were investigated by MTS assay and Matrigel-double chamber assay. To answer our main question, we performed angiogenesis assay used an in vitro model consisting of co-cultivated tumor cells and stromal cells.

RESULTS

IL-1alpha mRNA and protein were detected in highly metastatic colon cancer cells (WiDr and HT-29). Recombinant IL-1alpha significantly enhanced growth and invasiveness of human umbilical vein endothelial cells (HUVEC) (P < 0.01). Moreover, HUVEC growth and migration were significantly enhanced by WiDr compared to control (without co-culture) or Caco-2 (P < 0.05). Exogenous rIL-1alpha significantly enhanced HUVEC tube-like formation in a dose-dependent manner (P < 0.01) in a HUVEC/fibroblast co-cultivation system. Moreover, WiDr significantly enhanced HUVEC tubule formation compared with control or Caco-2 (P < 0.01).

CONCLUSION

Based on these findings, we conclude that colon cancer cell-derived IL-1alpha up-regulates angiogenesis by modulating stromal cells within the tumor cells' microenvironment.