Female B6D2F1 Mice Research Articles

Intracytoplasmic oxidative stress reverses epigenetic modifications in polycystic ovary syndrome.

In polycystic ovary syndrome (PCOS), substantial genetic and environmental alterations, along with hyperandrogenism, affect the quality of oocytes and decrease ovulation rates. To determine the mechanisms underlying these alterations caused specifically by an increase in plasma androgens, the present study was performed in experimentally-induced PCOS mice. As the study model, female B6D2F1 mice were treated with dehydroepiandrosterone (DHEA, 6mg per 100g bodyweight). After 20 days, oocytes at the germinal vesicle and metaphase II stages were retrieved from isolated ovaries and subsequent analyses of oocyte quality were performed for each mouse. DHEA treatment resulted in excessive abnormal morphology and decreased polar body extrusion rates in oocytes, and was associated with an increase in oxidative stress. Analysis of fluorescence intensity revealed a significant reduction of DNA methylation and dimethylation of histone H3 at lysine 9 (H3K9) in DHEA-treated oocytes, which was associated with increased acetylation of H4K12. Similarly, mRNA expression of DNA methyltransferase-1 and histone deacetylase-1 was significantly decreased in DHEA-treated mice. There was a significant correlation between excessive reactive oxygen species (ROS) production and increased histone acetylation, which is a novel finding and may provide new insights into the mechanism causing PCOS. The results of the present study indicate that epigenetic modifications of oocytes possibly affect the quality of maturation and ovulation rates in PCOS, and that the likely mechanism may be augmentation of intracytoplasmic ROS.

Early markers of phenotypic heterogeneity in the induced model of systemic lupus erythematosus

The study aimed at evaluating the predisposition for development of different variants of SLE based on an inflammatory response in intact mice. Materials and methods. Low-dose systemic inflammatory response was modeled by the administration of lipopolysaccharide (LPS) of E. coli (strain 111: B4) by intact B6D2F1 recipients in the dose of 10 ng/mouse or 1 μg / mouse. We evaluated the number of leukocytes, neutrophils, and lymphocytes in the blood, the index of neutrophils / lymphocytes (ratio N/L), and the level of free DNA (cf DNA cell free) in dynamics. The first day after LPS injection we induced SLE model: the female B6D2F1 mice were injected 60–70 x 106 spleen cells of the DBA / 2 parent mice twice with interval five days. Three months after the induction of the model, the level of protein in the urine was measured twice: the mice with proteinuria 3 mg/ml and more were assigned to the group SLEnephritis+, and mice with less than 3 mg/ml of protein in the urine were assigned to the group SLEnephritis–. Results. It was established that administration of LPS does not change the frequency of nephritis in mice. The retrospective analysis of the number of leukocytes, neutrophils, and lymphocytes does not allow the prediction of the development of nephritis. We observed a significant increase in the frequency and the absolute value of the N/L index at week 8 relative to 4 weeks four weeks before the appearance of proteinuria in the group of mice SLEnephritis+ in contrast to mice SLEnephritis– when LPS was administered at a dose of 10 ng/mouse. Mice SLEnephritis+ and SLEnephritis– show different kinetics of the inflammatory response by an increase in the N/L index every subsequent hour relative to the previous one when LPS was administered at a dose of 1 μg/mouse. The dynamics of the cfDNA level is similar to the kinetics of an index N/L in the group SLEnephritis+ and the SLEnephritis–. The data obtained indicate the possibility of using of the index N/L and cfDNA level as a parameter of inflammatory response in mice and prediction of the susceptibility the development of nephritis.

Effects of Angiopoietin-2 on Transplanted Mouse Ovarian Tissue.

Transplantation of ovarian tissue (OT) is currently the only clinical option to restore fertility with cryopreserved OT. However, follicle loss caused by ischemia and slow revascularization occurs in transplanted OT. To shorten the ischemic period and promote angiogenesis, some angiogenic factors have been used. Angiopoietin-2 (Ang2) is one of the major angiogenic factors and has been reported to promote blood vessels and increase vascular permeability in ischemic and/or hypoxic environment. This study was performed to investigate the effects of Ang2 on follicle integrity and revascularization of transplanted mouse OT. Five-week-old B6D2F1 female mice were divided into a control group and two Ang2 groups, followed by ovary collection and vitrification. After warming, the ovaries were autotransplanted into kidney capsules with/without Ang2 injection (50 or 500 ng/kg), and then the mice were sacrificed at days 2, 7, 21, and 42 after transplantation. A total 2,437 follicles in OT grafts were assessed for follicular density, integrity, and classification by using hematoxylin and eosin staining. Apoptosis and revascularization were evaluated by using TUNEL assay and CD31 immunohistochemistry, respectively. Serum follicle-stimulating hormone (FSH) levels were measured by using enzyme-linked immunosorbent assay. Both Ang2 groups showed remarkable increase in morphologically intact follicle ratio across all grafting durations except D21. The numbers of CD31(+) vessels were significantly increased in both Ang2 groups compared with the control group at all durations, except in the 50 ng Ang2 group at D42. However, the mean numbers of follicles of the grafts, apoptosis ratios, and serum FSH levels showed no significant differences among the groups. Our results show that Ang2 treatment significantly increased the intact follicle ratios and the number of blood vessels of the mouse OT grafts. However, further studies performed with large animal or human OT are necessary before clinical application for fertility preservation in cancer patients, and the reliability of the systemic effects of Ang2 should be verified.

Effects of the histone deacetylase inhibitor 'Scriptaid' on the developmental competence of mouse embryos generated through round spermatid injection.

Can the histone deacetylase inhibitor Scriptaid improve the efficiency of the development of round spermatid injection (ROSI)-fertilized embryos in a mouse model? Treatment of ROSI mouse zygotes with Scriptaid increased the expression levels of several development-related genes at the blastocyst stage, resulting in more efficient in vitro development of the blastocyst and an increased birth rate of ROSI-derived embryos. The full-term development of embryos derived through ROSI is significantly lower than that following ICSI in humans and other species. Oocytes, spermatozoa and round spermatids were collected from BDF1 (C57BL/6 × DBA/2) mice. For in vitro development experiments, mouse ROSI-derived zygotes were treated with Scriptaid at different concentrations (0, 125, 250, 500 and 1000 nM) and for different exposure times (0, 6, 10, 16 or 24 h). Next, blastocysts of the optimal Scriptaid-treated group and the non-treated ROSI group were separately transferred into surrogate ICR mice to compare in vivo development with the ICSI group (control). Each experiment was repeated at least three times. Metaphase II (MII) oocytes, spermatozoa and round spermatids were obtained from sexually mature BDF1 female or male mice. The developmental potential of embryos among the three groups (the ICSI, ROSI and optimal Scriptaid-treated ROSI groups) was assessed based on the rates of obtaining zygotes, two-cell stage embryos, four-cell stage embryos, blastocysts and full-term offspring. In addition, the expression levels of development-related genes (Oct4, Nanog, Klf4 and Sox2) were analysed using real-time PCR, and the methylation states of imprinted genes (H19 and Snrpn) in these three groups were detected using methylation-specific PCR (MS-PCR) sequencing following bisulfite treatment. The in vitro experiments revealed that treating ROSI-derived zygotes with 250 nM Scriptaid for 10 h significantly improved the blastocyst formation rate (59%) compared with the non-treated group (38%) and further increased the birth rates of ROSI-derived embryos from 21% to 40% in vivo. Moreover, in ROSI-derived embryos, the expression of the Oct4, Nanog and Sox2 genes at the blastocyst stage was decreased, but the optimal Scriptaid treatment restored expression to a level similar to their ICSI counterparts. In addition, Scriptaid treatment moderately repaired the abnormal DNA methylation pattern in the imprinting control regions (ICRs) of H19 and Snrpn. N/A LIMITATIONS, REASONS FOR CAUTION: Because of the ethics regarding the use of human gametes for ROSI studies, the mouse model was used as an approach to explore the effects of Scriptaid on the developmental potential of ROSI-derived embryos. However, to determine whether these findings can be applied to humans, further investigation will be required. Scriptaid treatment provides a new means of improving the efficiency and safety of clinical human ROSI. The study was financially supported through grants from the National Key Research Program of China (No. 2016YFC1304800); the National Natural Science Foundation of China (Nos: 81170756, 81571486); the Natural Science Foundation of Shanghai (Nos: 15140901700, 15ZR1424900) and the Programme for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning. There are no conflicts of interest to declare.

Effect of hexavalent chromium-treated sperm on in vitro fertilization and embryo development.

Hexavalent chromium (Cr(VI)) is an environmental contaminant that is associated with reproductive abnormalities in both humans and animals. In the present study, we evaluated the cytotoxic effect of Cr(VI) on sperm function and subsequent embryo development after in vitro fertilization (IVF). Sperm obtained from BDF1 male mice were treated with potassium dichromate (0, 3.125, 6.25, 12.5, 25, or 50 μM) for 3 h. Cr(VI) significantly decreased sperm viability and acrosome reaction with increasing dose. These Cr(VI)-treated sperms were further used for IVF of oocytes obtained from BDF1 female mice. Results showed that Cr(VI)-treated sperm caused a significant reduction in IVF success, higher developmental arrest at the two-cell stage of embryos, and delayed blastocyst formation with increasing dose. In particular, most blastocysts from the Cr(VI)-treated sperm resulted in hatching failure as well as decreased inner cell mass and trophectoderm (TE). Furthermore, blastocysts obtained from Cr(VI)-treated sperm showed lower expression of not only TE-associated genes (eomes, cdx2, and krt8) but also pluripotent marker genes (sox2, pou5f1, and klf4) that are responsible for further embryo development of blastocyst embryos. The results of our current study showed that Cr(VI)-treated sperm had negative effects on oocyte fertilization and subsequent embryo development.

Embryonic development after exposure of mouse oocyte to various amount of ovarian endometriotic fluid.

This study assesses the fertilization and blastocyst-forming rate in mice cumulus-oocyte complexes (COCs) after the exposure of human ovarian endometriotic fluid. Endometriotic fluid was obtained from a single patient by aspiration at the time of a laparoscopic cystectomy and serially diluted. COCs were obtained from 46-week-old female BDF1 mice. After exposure to ovarian endometriotic fluid for five minutes, the COCs were washed three times and the oocytes were then fertilized by mice sperm. The fertilization and blastocyst formation rate and the proportion of hatching/hatched blastocyst in the four treatment groups were not inferior to those in non-exposure group.

Skin wound trauma, following high-dose radiation exposure, amplifies and prolongs skeletal tissue loss

The present study investigated the detrimental effects of non-lethal, high-dose (whole body) γ-irradiation on bone, and the impact that radiation combined with skin trauma (i.e. combined injury) has on long-term skeletal tissue health. Recovery of bone after an acute dose of radiation (RI; 8Gy), skin wounding (15–20% of total body skin surface), or combined injury (RI+Wound; CI) was determined 3, 7, 30, and 120days post-irradiation in female B6D2F1 mice and compared to non-irradiated mice (SHAM) at each time-point. CI mice demonstrated long-term (day 120) elevations in serum TRAP 5b (osteoclast number) and sclerostin (bone formation inhibitor), and suppression of osteocalcin levels through 30days as compared to SHAM (p<0.05). Radiation-induced reductions in distal femur trabecular bone volume fraction and trabecular number through 120days post-exposure were significantly greater than non-irradiated mice (p<0.05) and were exacerbated in CI mice by day 30 (p<0.05). Negative alterations in trabecular bone microarchitecture were coupled with extended reductions in cancellous bone formation rate in both RI and CI mice as compared to Sham (p<0.05). Increased osteoclast surface in CI animals was observed for 3days after irradiation and remained elevated through 120days (p<0.01). These results demonstrate a long-term, exacerbated response of bone to radiation when coupled with non-lethal wound trauma. Changes in cancellous bone after combined trauma were derived from extended reductions in osteoblast-driven bone formation and increases in osteoclast activity.

Orally active αvβ3 integrin inhibitor MK-0429 reduces melanoma metastasis.

Melanoma remains one of the most aggressive types of cancer with a historically low survival rate. The αvβ3 integrin is involved in the progression of malignant melanoma. In the present study, the efficacy of MK-0429, a selective inhibitor of the αvβ3 integrin, was evaluated for its potential in the prevention of melanoma metastasis. Female B6D2F1 mice injected via the tail vein with murine B16F10 melanoma developed lung metastases within ~10 days. In the first experiment, the prevention of lung metastasis was assessed in the model treated with either vehicle, MK-0429 at 100 and 300 mg/kg orally twice daily or cyclophosphamide at 300 mg/kg, i.p. once daily. Study endpoints included determination of the study time period to achieve metastasis in lungs in this model, evaluation of the health effects on the study animals, the total number of lung colonies identified and lung tumor area. Unlike cyclophosphamide, the MK-0429 treatment did not lead to a significant weight reduction in mice. MK-0429 at 100 and 300 mg/kg reduced the number of metastatic tumor colonies by 64 and 57%, respectively, and the high dose also reduced the tumor area by 60% as compared to the vehicle. The second experiment employed B16F10 luciferase-expressing cells to examine the de novo progression of melanoma metastasis over 15 days with bioluminescent imaging of mice treated with MK-0429 at 300 mg/kg as compared to the vehicle. Tumor burden progressively advanced in the lungs of the B16F10-treated animals. However, MK-0429 reduced the progression of ventral and dorsal lung metastases by 22 and 38%, respectively, as compared to the vehicle, by study completion. Quantification of ex vivo tumor burden showed a 30–40% reduction in lung colonies by MK-0429. The two studies collectively demonstrated that MK-0429 was safe and efficacious in significantly decreasing melanoma metastasis in the lungs. The results emphasized the potential of MK-0429 as a novel, therapeutic agent for the prevention of metastatic melanoma.

Antioxidant supplementation during in vitro culture improves mitochondrial function and development of embryos from aged female mice.

Maternal aging results in reduced oocyte and blastocyst quality, thought to be due, in part, to mitochondrial dysfunction and accumulation of reactive oxygen species. To reduce oxidative stress, the antioxidants α-lipoic acid (ALA; 10µM), α-tocopherol (250µM), hypotaurine (1mM) and N-acetylcysteine (NAC; 1mM), and sirtuin (100ngmL(-1)) were added to embryo culture medium (AntiOX) and compared with a control (CON) without antioxidants to assess blastocyst development after in vitro maturation and fertilisation of oocytes from aged B6D2F1 female mice (13.5 months). Development to the blastocyst stage increased in the AntiOX compared with CON group (87.6% vs 72.7%, respectively; P<0.01), in addition to higher mitochondrial membrane potential and ATP levels in the AntiOX group. Expression of genes associated with oxidative stress (PI3K, FOXO3A and GLRX2) was upregulated in the CON compared with AntiOX group. In addition to AntiOX, a medium containing only NAC and ALA (rAntiOX) was used to culture embryos from young CF1 females (6-8 weeks). More blastocysts developed in the rAntiOX compared with CON group (64.1% vs 43.3%, respectively; P<0.01), although AntiOX (48.0% blastocysts) did not result in improved development in young mice. Antioxidants improved mitochondrial activity, gene expression and development in embryos of older female mice, whereas a reduced level of antioxidants during culture was beneficial to embryos from young mice.

41 UPDATING THE ZONA-FREE METHOD FOR MOUSE CLONING USING HM1 EMBRYONIC STEM CELLS

The zona-free method of SCNT designed for bovine and pig cloning (Booth et al. 2001; Vajta et al. 2001; Oback et al. 2003) was successfully used for horse (Galli et al. 2003). Although simple and efficient in farm animals, its application in the mouse met several problems (Ribas et al. 2005, 2006). The aim of our work was to produce cloned mice using HM1 embryonic stem (ES)cells adapting a zona-free method. Seven- to 24-week-old superovulated B6D2F1 female mice were used as oocytes donors. Cumulus cells were removed by 0.3% hyaluronidase and the zona pellucida by 0.5% pronase in KSOM-HEPES (KSOM-H) 1 h later (Ribas et al. 2006) or immediately after hyaluronidase treatment at 37°C. The HM1 ES cells were cultured in KnockOut DMEM supplemented with leukemia inhibitory factor and 15% fetal bovine serum with or without 2i (Ying et al. 2008) and were synchronized at M phase by 3 ng mL–1 nocodazole for 3 h before fusion. Only spherical cells were selected for NT. Metaphase II chromosome spindle complexes were removed by micromanipulation in KSOM-H medium with 5 μg mL–1 cytochalasin B. Lectin-treated enucleated oocytes were attached to the donor cells in KSOM-H with nocodazole and fused by 2 pulses of 1.3 kV cm–1 DC for 30 μs in 0.3 M mannitol medium. Following 10- to 15-min incubation in KSOM-H, the fusion was assessed and repeated if the constructs were nonfused. Cloned embryos were activated in 1 mM SrCl2 in Ca2+-free KSOM medium for 2 to 2.5 or 5 to 6 h and cultured in 20-μL KSOM droplets using the well-of-the-well (WOW) method (Vajta et al. 2000) under mineral oil at 37°C and 5% CO2. Day 4 compacted morulae and blastocysts were surgically transferred into the uterus of Day-2.5 pseudopregnant recipients that were sacrificed on Day 19.5 to examine fetal development. The donor mice age was important for oocyte survival: ~16% of oocytes of 7- to 10-week-old mice lysed before or during fusion in 33% of experiments (n experiments = 15), whereas oocytes of older mice were not sensitive to enzymatic treatment and electric impulses even after 3 fusion rounds (n = 19). The time of pronase treatment did not affect oocyte survival, whereas extending the time between hyaluronidase treatment and enucleation revealed self-activation in ~25% of oocytes. The fusion efficiency of ES cells was significantly lower compared with serum-starved fibroblasts (61%, n = 623 v. 100%, n = 80). The duration of SrCl2 treatment did not affect embryo development (cleavage: 82% v. 84%; Day 4 blastocysts: 49% v. 52%). ES cell culture with 2i increased Day 4 blastocyst development (60.7% v. 50.4%; P = 0.07), and their ability to implant (52.6% v. 38.2%; P = 0.06). Moreover, only NT embryos derived from 2i-ES cells developed to term (8.2%, n = 5; P = 0.08), and produced live fetuses (4.9%, n = 3). In light of these results, the fusion of ES cells remains the critical step in the mouse zona-free protocol.Partially supported by grant Superpig from Regione Lombardia.

Effects of T-2 mycotoxin on in vitro development and chromatin status of mouse embryos in preimplantation stages.

T-2 toxin is a mycotoxin produced by phytopathogenic fungi of the Fusarium genus and has many well-studied deleterious effects on mammalian cells and reproductive tract. Despite the wide scale studies, the effects on preimplantation stage embryos are lacking. The aim of our study was to investigate the impact of T-2 on the cleavage stage of mouse embryos with regard to development to blastocysts and nuclear chromatin status.Six-weeks-old BDF1 female mice were superovulated and placed together overnight with mature males. Zygotes were flushed 20 h after human chorionic gonadotropin injection and divided randomly into treated (supplemented with 0.5, 0.75, and 1 ng/ml T-2) and nontreated (control) groups. Embryos were cultured in vitro for 96 h. Developmental stage was evaluated in the 72(nd)- and 96(th)-h for assessment of development dynamics. At the end of culture period, blastocysts from treated and control groups with normal morphology were selected for nuclear chromatin analysis. Blastocysts were categorized (grade A, B, and C) depending on the proportion of blasomeres with micronuclei and/or lobulated nuclei.Our data show significant decrease in the proportions of blastocysts in the 0.75 and 1 ng/ml toxin-supplemented groups compared with the control group. Blastocyst rate did not differ in embryos treated with 0.5 ng/ml T-2 but 24 h delay was found in blastocoel formation in all the treated groups. Only grade A (21.1%) and B (78.9%) blastocysts were found in low-toxin-contaminated group similar to the control ones (50-50%). Grade C embryos appeared in the 0.75 ng/ml (10%) treated group and the rate increased significantly (33.3%) in the highest contaminated group.T-2 mycotoxin has a harmful effect on early embryo development which results in decreased blastocyst proportion, delayed blastulation, and increased rate of chromatin damage.

The impact of vitrification on murine germinal vesicle oocyte In vitro maturation and aurora kinase A protein expression.

Investigate the effect of vitrification on in vitro maturation (IVM) and expression of Aurora kinases A, B, and C in germinal vesicle (GV)-stage oocytes. GV-stage oocytes from B6D2F1 female mice 7-11weeks of age were vitrified after collection, thawed, and matured in vitro for 0, 4, 8, and 12h (hrs). The rate of germinal vesicle breakdown (GVBD), spindle apparatus assembly, and Aurora kinase mRNA and protein expression during IVM was measured. Oocyte vitrification was associated with significant delays in both GVBD and normal spindle apparatus assembly at 4 and 8h of IVM (p < 0.05). There was no difference in mRNA levels between control and vitrified oocytes for any of the Aurora kinases. Aurora A protein levels were reduced in vitrified compared to control oocytes at 0h (p = 0.008), and there was no difference at 4 and 8h (p = 0.08 and 0.69, respectively) of IVM. Vitrified oocytes have delayed GVBD and normal spindle assembly during in vitro maturation. Reduced levels of Aurora A protein immediately post-thaw may be associated with the impaired oocyte maturation manifested by the delayed progression through meiosis I and II, and the atypical timing of the formation of meiotic spindles in vitrified GV-stage oocytes.

Effect of Human Endothelial Progenitor Cell (EPC)- or Mouse Vascular Endothelial Growth Factor-Derived Vessel Formation on the Survival of Vitrified/Warmed Mouse Ovarian Grafts

The aim of this study was to evaluate the effectiveness of improving angiogenesis at graft sites on the survival of follicles in transplanted ovarian tissue. Matrigel containing 5 × 105 of cord blood-derived endothelial progenitor cells (EPCs) or 200 ng of mouse vascular endothelial growth factor (VEGF) was injected subcutaneously into BALB/c-Nu mice. After 1 week, vitrified/warmed ovaries from female B6D2F1 mice were subcutaneously transplanted into the injection sites. After 1, 2, and 4 weeks posttransplantation, the ovaries were recovered and subjected to histological analysis. Oocytes were collected from the transplanted ovaries, and their fertilization, embryonic development, and delivery were also observed. Vitrified/warmed ovaries transplanted into EPC- or VEGF-treated sites developed more blood vessels and showed better follicle survival than those transplanted into sham-injected sites. Normal embryonic development and consequent live births were obtained using oocytes recovered from cryopreserved/transplanted ovaries. Treatment with EPCs or VEGF could prevent the ischemic damage during the early revascularization stage of ovarian transplantation.

Effect of Imatinib Coadministration on in Vitro Oocyte Acquisition and Subsequent Embryo Development in Cyclophosphamide-Treated Mice

The study aimed to investigate the effect of imatinib coadministration on in vitro oocyte acquisition and subsequent embryo development in cyclophosphamide (Cp)-treated mice. Female BDF1 mice were injected with 5 IU equine chorionic gonadotropin (eCG) followed by 5 IU human chorionic gonadotropin 48 hours later and then oocytes were retrieved 14 hours later. Twenty-four hours prior to eCG administration, 25, 50, or 75 mg/kg Cp with or without 7.5 mg/kg imatinib was injected. In the 25 and 50 mg/kg Cp groups, imatinib coadministration significantly enhanced the percentage of mature oocytes (+16.4% and +10.4%) and significantly decreased the percentage of dead oocytes (-25.9% and -15.3%). Imatinib coadministration significantly enhanced the fertilization rate (FR) in the 50 mg/kg Cp group (+12.2%). Intraoocyte spindle integrity was significantly affected by Cp and was rescued by imatinib coadministration. Coadministration of imatinib prior to ovarian stimulation has the benefit of enhancing oocyte maturity and the in vitro FR in Cp-treated mice .

PD9-06 GABAPENTIN SUPPRESSES THE MICTURITION REFLEXES AND VISCERAL PAIN-RELATED VISCEROMOTOR REFLEX IN THE MICE WITH CYCLOPHOSPHAMIDE-INDUCED CYSTITIS

You have accessJournal of UrologyInfections/Inflammation of the Genitourinary Tract: Interstitial Cystitis1 Apr 2014PD9-06 GABAPENTIN SUPPRESSES THE MICTURITION REFLEXES AND VISCERAL PAIN-RELATED VISCEROMOTOR REFLEX IN THE MICE WITH CYCLOPHOSPHAMIDE-INDUCED CYSTITIS Huiyi Chang and Gamal Ghoniem Huiyi ChangHuiyi Chang More articles by this author and Gamal GhoniemGamal Ghoniem More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.788AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The present study is to investigate the lower urinary tract function and visceral pain-related visceromotor reflex (VMR) in a mouse model with cyclophosphamide (CYP)-induced cystitis. A potential method integrating sensing and diagnosing functionalities at the end of the study can offer physicians a powerful tool to examine the visceral pain and offer the treatment of Gabapentin to relieve the pain. METHODS A total of 12 female BDF1 mice were used. Mice were intraperitoneally given either 0.2 mL of saline (n=5) or 200 mg/kg of CYP (n=7) 48 hours before the urodynamic recordings. At the day of urodynamic recording session, the animals were anesthetized by urethane (1.5 g/kg, ip). The bladder pressure, EMG activity of EUS and VMR were obtained during the continuously saline infusion. RESULTS In CYP-treated group, signs of pain were observed during 48 hours. Longer duration of VMR (11 ± 2 sec) and shorter inter-contraction intervals (ICI, 62 ± 11 sec) were significantly (p<0.05) shown in CYP-treated group compared to the controls (5 ± 1 sec in VMR duration and 89 ± 16 sec in ICI). Gabapentin was then given (50 mg/kg, ip) in CYP-treated group. The effect of gabapentin started to affect the voiding contractions 1-2 hours after administration. Gabapentin gradually suppressed the EMG activity of EUS and VMR as well as bladder contractions in 1 hour. CONCLUSIONS Increased duration of VMR and decreased ICI showed respectively induced visceral pain and detrusor overactivity in CYP-treated group. Gabapentin have acted centrally to inhibit both somatic and parasympathetic nervous systems due to suppression of EMG activity of EUS and VMR, and detrusor contractions, respectively. BDF1 female mice is a suitable model to investigate the changes of urodynamic recording as well as the level of visceral pain and detrusor overactivity with CYP-induced cystitis. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e213-e214 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Huiyi Chang More articles by this author Gamal Ghoniem More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Dose-dependent embryotrophic effect of recombinant granulocyte-macrophage colony-stimulating factor and brain-derived neurotrophic factor in culture medium for mouse preimplantation embryo.

ObjectiveTo evaluate the dose effect of recombinant mouse granulocyte-macrophage colony-stimulating factor (rmGM-CSF) or brain-derived neurotrophic factor (BDNF) in culture medium on the development of in vitro fertilized mouse embryos.MethodsMature oocytes were retrieved from superovulated female BDF1 mice and inseminated by sperm from male BDF1 mice. On day 1, two-cell stage embryos were divided and cultured until day 5 in the embryo maintenance medium supplemented with 0, 1, 2, 5, or 10 ng/mL of rmGM-CSF or supplemented with 0, 5, 10, or 20 ng/mL of BDNF. Blastocyst formation rate and their cell numbers were assessed.ResultsThe blastocyst formation rate and the total cell count in blastocyst was similar in all the rmGM-CSF treatment groups when compared with the control. However, the blastocyst formation rate and the total cell count was significantly higher in the group supplemented with 10 ng/mL of BDNF compared with the control (63.9%, 45.8±11.5 vs. 52.3%, 38.0±6.8; P<0.05, respectively).ConclusionSupplementation of 10 ng/mL of BDNF enhanced the developmental potential of mouse preimplantation embryos, but supplementation of rmGM-CSF did not.

Optimization of irinotecan chronotherapy with P-glycoprotein inhibition

The relevance of P-glycoprotein (P-gp) for irinotecan chronopharmacology was investigated in female B6D2F1 mice. A three-fold 24h change in the mRNA expression of Abcb1b was demonstrated in ileum mucosa, with a maximum at Zeitgeber Time (ZT) 15 (p<0.001). No rhythm was found for abcb1a in ileum mucosa, or for Abcb1a/b in Glasgow osteosarcoma (GOS), a mouse tumor cell line moderately sensitive to irinotecan. Non-tumor-bearing mice received irinotecan (50mg/kg/day i.v.×4days) as a single agent or combined with P-gp inhibitor PSC833 (6.25mg/kg/day i.p.×4 days) at ZT3 or ZT15, respectively corresponding to the worst or the best irinotecan tolerability. Endpoints involved survival, body weight change and hematologic toxicity. Antitumor efficacy was studied in GOS-bearing mice receiving irinotecan (25, 30 or 40mg/kg/day×4days) and +/−PSC833 at ZT3 or ZT15, with survival, body weight change, and tumor growth inhibition as endpoints. Non-tumor bearing mice lost an average of 17% or 9% of their body weight according to irinotecan administration at ZT3 or ZT15 respectively (p<0.001). Dosing at ZT15 rather than ZT3 reduced mean leucopenia (9% vs 53%; p<0.001). PSC833 aggravated irinotecan lethal toxicity from 4 to ~60%. In tumor-bearing mice, body weight loss was ~halved in the mice on irinotecan or irinotecan–PSC833 combination at ZT15 as compared to ZT3 (p<0.001). PSC833–irinotecan at ZT15 increased tumor inhibition by ~40% as compared to irinotecan only at ZT15. In conclusion, P-gp was an important determinant of the circadian balance between toxicity and efficacy of irinotecan.

Addition of lysophosphatidic acid to mouse oocyte maturation media can enhance fertilization and developmental competence

Does exposure to lysophosphatidic acid (LPA) during in vitro maturation (IVM) enhance the maturation and developmental competence of mouse oocytes? Supplementation of IVM medium with 30 μM LPA enhanced the developmental competence of in vitro matured oocytes and so made them more comparable to in vivo matured control oocytes. LPA is a small phospholipid that acts as an extracellular signaling molecule by binding to and activating at least five G protein-coupled receptors. LPA has various biological actions, with both developmental and physiological effects. During IVM, LPA at six different doses (0, 1, 10, 30, 50 or 100 μM) was added into the TCM-199 medium. After maturation, the developmental competence and other parameters of the oocytes were assessed. Immature GV stage oocytes from 5- to 6-week-old female BDF-1 mice were incubated for 17-18 h in IVM medium containing 0, 1, 10 or 30 μM LPA and then either fertilized in vitro with epididymal sperm, or assessed for spindle morphology, mitochondrial membrane potential (ΔΨm) or the mRNA expression of a meiotic checkpoint gene (Mad2), a microtubule structure gene (Hook1), two maternally derived genes (Mater and Hsf1) and an apoptosis-related gene (Caspase6). The fertilized embryos were grown in vitro to assess blastocyst-formation rates, differential cell counts and apoptosis. Rates of maturation, fertilization and blastocyst formation and hatching were significantly higher in the 30 μM LPA-supplemented group (94.3, 96.3, 79.1 and 51.3%, respectively) than in the unsupplemented control (0 μM) group (80.5, 87.5, 61.3 and 37.8%, respectively) and more comparable to that of the in vivo matured oocytes (100, 96.5, 95.3 and 92.9%, respectively). LPA did not adversely affect mitochondrial activity, spindle integrity, blastocyst cell number, caspase positivity or Mad2 expression. Oocytes matured in 30 μM LPA had reduced Caspase6 expression, but Hook1, Mater and Hsf1 were up-regulated in all of the LPA-supplemented groups. Chromosomal aneuploidy in the resultant blastocysts and the production of normal pups were not assessed. Only mouse oocytes were assessed. Supplementation of IVM medium with 30 μM LPA may enhance the developmental competence of mouse oocytes without affecting apoptosis, spindle normalcy or mitochondrial integrity. This study was supported by a research grant (02-2012-021) from the Seoul National University Bundang Hospital. The authors declare that they have no competing interests.

Proliferative Activity and Subpopulation Pattern of Cells in Murine Thymus and Spleen on the Model of Graft-Versus-Host Chronic Reaction under Various Diurnal Regimens of IL-2 Administration

We studied the effects of IL-2 administration at different times of day to female B6D2F1 mice with experimental immunopathology, graft-versus-host chronic reaction induced by the administration of lymphoid cells from parental female DBA/2 mice. Recombinant murine IL-2 was injected subcutaneously at 10.00 (group 1) or 16.00 (group 2) after the first cell transfer. Evening administration of IL-2 in contrast to its morning injection prevented cell proliferation in the thymus and spleen, decreased the number of apoptotic splenocytes, significantly stimulated differentiation processes in the thymus, increased the amount of CD4 (+) 25 (high) thymocytes, and decreased the number of CD4 (+) 27 (low) splenocytes. These findings can serve as a prerequisite for the development of chronotherapeutic schemes for immunocorrection.

Subchronic toxicity and carcinogenicity studies of 1,2-dichloropropane inhalation to mice

The subchronic toxicity and carcinogenicity of 1,2-dichloropropane (DCP) in male and female B6D2F1 mice exposed to DCP by inhalation for 13 weeks or for 2 years was investigated. The DCP concentrations used were 50, 100, 200, 300 or 400 ppm (v/v) in the 13-week study, and 32, 80 or 200 ppm (v/v) in the 2-year study. Thirteen weeks inhalation exposure of mice to DCP caused death in the mice exposed to 300 ppm and above, and was found to induce hemolytic anemia and lesions of the liver, forestomach and heart. Two years exposure to DCP significantly increased the combined incidence of bronchiolo-alveolar adenomas and carcinomas in females and marginally increased the incidence of Harderian gland adenomas in males. As non-neoplastic lesion, atrophy and respiratory metaplasia in the olfactory epithelium, and respiratory metaplasia in the submucosal gland of the nasal cavity were increased. Thus, two years inhalation exposure to DCP is carcinogenic in female mice and there is a marginal evidence of carcinogenicity in males.