The Effect of Boron (B) and Copper (Cu) on the Microstructure and Graphite Morphology of Spheroidal Graphite Cast Iron.

This study examines the impacts of copper and boron in parts per million (ppm) on the microstructure and mechanical properties of spheroidal graphite cast iron (SCI). Boron's inclusion increases the ferrite content whereas copper augments the stability of pearlite. The interaction between the two significantly influences the ferrite content. Differential scanning calorimetry (DSC) analysis indicates that boron alters the enthalpy change of the α + Fe3C → γ conversion and the α → γ conversion. Scanning electron microscope (SEM) analysis confirms the locations of copper and boron. Mechanical property assessments using a universal testing machine show that the inclusion of boron and copper decreases the tensile strength and yield strength of SCI, but simultaneously enhances elongation. Additionally, in SCI production, the utilization of copper-bearing scrap and trace amounts of boron-containing scrap metal, especially in the casting of ferritic nodular cast iron, offers potential for resource recycling. This highlights the importance of resource conservation and recycling in advancing sustainable manufacturing practices. These findings provide critical insights into the effects of boron and copper on SCI's behavior, contributing to the design and development of high-performance SCI materials.

PKC-ß modulates Ca2+ mobilization through Stim1 phosphorylation.

BACKGROUND: Calcium ions play a pivotal role in cell proliferation, differentiation, and migration. Under basal conditions, the calcium level is tightly regulated; however, cellular activation by growth factors increase the ion level through calcium pumps in the plasma membrane and endoplasmic reticulum for calcium signaling. Orai1 is a major calcium channel in the cell membrane of non-excitable cells, and its activity depends on the stromal interaction molecule 1 (Stim1). Several groups reported that the store-operated calcium entry (SOCE) can be modulated through phosphorylation of Stim1 by protein kinases such as extracellular signal-regulated kinase (ERK), protein kinase A (PKA), and p21-activated kinase (PAK). PKC is a protein kinase that is activated by calcium and diacylglycerol (DAG), but it remains unclear what role activated PKC plays in controlling the intracellular calcium pool. OBJECTIVES: Here, we investigated whether PKC-ß controls intracellular calcium dynamics through Stim1. METHODS: Several biochemical methods such as immune-precipitation, site directed mutagenesis, in vitro kinase assay were employed to investigate PKC interaction with and phosphorylation of Stim1. Intracellular calcium mobilization, via Stim1 mediated SOCE channel, were studied using in the presence of PKC activator or inhibitor under a confocal microscope. RESULTS: Our data demonstrate that PKC interacts with and phosphorylates Stim1 in vitro. phosphorylation of Stim1 at its C-terminal end appears to be important in the regulation of SOCE activity in HEK293 and HeLa cells. Additionally, transient intracellular calcium mobilization assays demonstrate that the SOCE activity was inhibited by PKC activators or activated by PKC inhibitors. CONCLUSION: In sum, our data suggest a repressive role of PKC in regulating calcium entry through SOCE.

The Anticancer Effects of Garlic Extracts on Bladder Cancer Compared to Cisplatin: A Common Mechanism of Action via Centromere Protein M.

Although garlic induces apoptosis in cancer cells, it is unclear whether the effects are similar to those of cisplatin against bladder cancer (BC). Therefore, this study investigated whether garlic extracts and cisplatin show similar activity when used to treat BC. The effect of garlic on T24 BC cell line was examined in a BALB/C-nude mouse xenograft model and compared with that of cisplatin. Tissue microarray analysis and gene network analysis were performed to identify differences in gene expression by control tumors and tumors exposed to garlic extract or cisplatin. Investigation of gene expression based on tissues from 165 BC patients and normal controls was then performed to identify common targets of garlic and cisplatin. Tumor volume and tumor weight in cisplatin (0.05[Formula: see text]mg/kg)- and garlic-treated mice were significantly smaller than those in negative control mice. However, cisplatin-treated mice also showed a significant reduction in body weight. Microarray analysis of tumor tissue identified 515 common anticancer genes in the garlic and cisplatin groups ([Formula: see text]). Gene network analysis of 252 of these genes using the Cytoscape and ClueGo software packages mapped 17 genes and 9 gene ontologies to gene networks. BC (NMIBC and MIBC) patients with low expression of centromere protein M (CENPM) showed significantly better progression-free survival than those with high expression. Garlic extract shows anticancer activity in vivo similar to that of cisplatin, with no evident of side effects. Both appear to act by targeting protein-DNA complex assembly; in particular, expression of CENPM.

Protein Expression Level of Skin Wrinkle-Related Factors in Hairless Mice Fed Hyaluronic Acid.

The aim of this study was to evaluate the wrinkle improving effect of hyaluronic acid intakes. Wrinkles were induced by exposing the skin of hairless mice to ultraviolet B (UVB) irradiation for 14 weeks. Hyaluronic acid was administered to the mice for 14 weeks including 4 weeks before experiments. Skin tissue was assayed by enzyme-linked immunosorbent assay to determine protein expression of wrinkle-related markers. The group supplemented with high concentrations of hyaluronic acid appeared significantly better than control group for collagen, matrix metalloproteinase 1, interleukin (IL)-1ß, and IL-6 assay. Transforming growth factor-ß1 (TGF-ß1) and hyaluronic acid synthase 2 (HAS-2) were not shown to be significantly different. In conclusion, hyaluronic acid administration regulated expression levels of proteins associated with skin integrity, and improved the wrinkle level in skin subjected to UVB irradiation.

Establishment and antitumor effects of dasatinib and PKI-587 in BD-138T, a patient-derived muscle invasive bladder cancer preclinical platform with concomitant EGFR amplification and PTEN deletion.

Muscle-invasive bladder cancer (MIBC) consists of a heterogeneous group of tumors with a high rate of metastasis and mortality. To facilitate the in-depth investigation and validation of tailored strategies for MIBC treatment, we have developed an integrated approach using advanced high-throughput drug screening and a clinically relevant patient-derived preclinical platform. We isolated patient-derived tumor cells (PDCs) from a rare MIBC case (BD-138T) that harbors concomitant epidermal growth factor receptor (EGFR) amplification and phosphatase and tensin homolog (PTEN) deletion. High-throughput in vitro drug screening demonstrated that dasatinib, a SRC inhibitor, and PKI-587, a dual PI3K/mTOR inhibitor, exhibited targeted anti-proliferative and pro-apoptotic effects against BD-138T PDCs. Using established patient-derived xenograft models that successfully retain the genomic and molecular characteristics of the parental tumor, we confirmed that these anti-tumor responses occurred through the inhibition of SRC and PI3K/AKT/mTOR signaling pathways. Taken together, these experimental results demonstrate that dasatinib and PKI-587 might serve as promising anticancer drug candidates for treating MIBC with combined EGFR gene amplification and PTEN deletion.

Sensitive Tumorigenic Potential Evaluation of Adult Human Multipotent Neural Cells Immortalized by hTERT Gene Transduction.

Stem cells and therapeutic genes are emerging as a new therapeutic approach to treat various neurodegenerative diseases with few effective treatment options. However, potential formation of tumors by stem cells has hampered their clinical application. Moreover, adequate preclinical platforms to precisely test tumorigenic potential of stem cells are controversial. In this study, we compared the sensitivity of various animal models for in vivo stem cell tumorigenicity testing to identify the most sensitive platform. Then, tumorigenic potential of adult human multipotent neural cells (ahMNCs) immortalized by the human telomerase reverse transcriptase (hTERT) gene was examined as a stem cell model with therapeutic genes. When human glioblastoma (GBM) cells were injected into adult (4-6-week-old) Balb/c-nu, adult NOD/SCID, adult NOG, or neonate (1-2-week-old) NOG mice, the neonate NOG mice showed significantly faster tumorigenesis than that of the other groups regardless of intracranial or subcutaneous injection route. Two kinds of ahMNCs (682TL and 779TL) were primary cultured from surgical samples of patients with temporal lobe epilepsy. Although the ahMNCs were immortalized by lentiviral hTERT gene delivery (hTERT-682TL and hTERT-779TL), they did not form any detectable masses, even in the most sensitive neonate NOG mouse platform. Moreover, the hTERT-ahMNCs had no gross chromosomal abnormalities on a karyotype analysis. Taken together, our data suggest that neonate NOG mice could be a sensitive animal platform to test tumorigenic potential of stem cell therapeutics and that ahMNCs could be a genetically stable stem cell source with little tumorigenic activity to develop regenerative treatments for neurodegenerative diseases.

Application of single-cell RNA sequencing in optimizing a combinatorial therapeutic strategy in metastatic renal cell carcinoma.

BACKGROUND: Intratumoral heterogeneity hampers the success of marker-based anticancer treatment because the targeted therapy may eliminate a specific subpopulation of tumor cells while leaving others unharmed. Accordingly, a rational strategy minimizing survival of the drug-resistant subpopulation is essential to achieve long-term therapeutic efficacy. RESULTS: Using single-cell RNA sequencing (RNA-seq), we examine the intratumoral heterogeneity of a pair of primary renal cell carcinoma and its lung metastasis. Activation of drug target pathways demonstrates considerable variability between the primary and metastatic sites, as well as among individual cancer cells within each site. Based on the prediction of multiple drug target pathway activation, we derive a combinatorial regimen co-targeting two mutually exclusive pathways for the metastatic cancer cells. This combinatorial strategy shows significant increase in the treatment efficacy over monotherapy in the experimental validation using patient-derived xenograft platforms in vitro and in vivo. CONCLUSIONS: Our findings demonstrate the investigational application of single-cell RNA-seq in the design of an anticancer regimen. The approach may overcome intratumoral heterogeneity which hampers the success of precision medicine.

Antioxidant and anti-ageing activities of citrus-based juice mixture.

The production of excessive reactive oxygen species by exposure to oxidative stress and solar radiation are primary factors in skin damage. We examined the effects of a citrus-based juice mixture and its bioactive compounds on antioxidant and anti-ageing activities in human dermal fibroblasts and hairless mice via the regulation of antioxidant enzymes and the mitogen-activated protein kinase pathway. The citrus-based juice mixture reduced H2O2-induced cell damage and intracellular reactive oxygen species production in human dermal fibroblasts. Citrus-based juice mixture pretreatment suppressed the activation of the H2O2-mediated mitogen-activated protein kinase pathway by activating the expression of activator protein 1 and matrix metalloproteinases. Moreover, it increased the expression levels of antioxidant enzymes such as glutathione reductase, catalase and manganese superoxide dismutase. In addition, oral administration of the citrus-based juice mixture decreased skin thickness and wrinkle formation and increased collagen content on an ultraviolet light B-exposed hairless mouse. These results indicate that the citrus-based juice mixture is a potentially healthy beverage for the prevention of oxidative stress-induced premature skin ageing.

Natural killer (NK) cells inhibit systemic metastasis of glioblastoma cells and have therapeutic effects against glioblastomas in the brain.

BACKGROUND: Glioblastoma multiforme (GBM) is characterized by extensive local invasion, which is in contrast with extremely rare systemic metastasis of GBM. Molecular mechanisms inhibiting systemic metastasis of GBM would be a novel therapeutic candidate for GBM in the brain. METHODS: Patient-derived GBM cells were primarily cultured from surgical samples of GBM patients and were inoculated into the brains of immune deficient BALB/c-nude or NOD-SCID IL2Rgamma(null) (NSG) mice. Human NK cells were isolated from peripheral blood mononucleated cells and expanded in vitro. RESULTS: Patient-derived GBM cells in the brains of NSG mice unexpectedly induced spontaneous lung metastasis although no metastasis was detected in BALB/c-nude mice. Based on the difference of the innate immunity between two mouse strains, NK cell activities of orthotopic GBM xenograft models based on BALB/c-nude mice were inhibited. NK cell inactivation induced spontaneous lung metastasis of GBM cells, which indicated that NK cells inhibit the systemic metastasis. In vitro cytotoxic activities of human NK cells against GBM cells indicated that cytotoxic activity of NK cells against GBM cells prevents systemic metastasis of GBM and that NK cells could be effective cell therapeutics against GBM. Accordingly, NK cells transplanted into orthotopic GBM xenograft models intravenously or intratumorally induced apoptosis of GBM cells in the brain and showed significant therapeutic effects. CONCLUSIONS: Our results suggest that innate NK immunity is responsible for rare systemic metastasis of GBM and that sufficient supplementation of NK cells could be a promising immunotherapeutic strategy for GBM in the brain.

The Synergistic Local Immunosuppressive Effects of Neural Stem Cells Expressing Indoleamine 2,3-Dioxygenase (IDO) in an Experimental Autoimmune Encephalomyelitis (EAE) Animal Model.

Neurodegenerative diseases provoke robust immunological reactions in the central nervous system (CNS), which further deteriorate the neural tissue damage. We hypothesized that the expression levels of indoleamine 2,3-dioxygenase (IDO), an enzyme that has potent immune suppressive activities, in neural stem cells (NSCs) would have synergistic therapeutic effects against neurodegenerative diseases, since NSCs themselves have low IDO expression. In this study, the synergistic immune suppressive effects of rat fetal NSCs expressing IDO (rfNSCs-IDO) were validated by mixed leukocyte reaction (MLR) in vitro and an experimental autoimmune encephalomyelitis (EAE) animal model in vivo. rfNSCs-IDO showed significantly more suppressive effects on T cell proliferation in the MLR compared to control rfNSCs (rfNSCs-Cont). Importantly, IDO inhibition using 1-methyl-DL-tryptophan (1-MT), an IDO inhibitor, reversed the synergistic effects, confirming IDO-specific effects in rfNSCs-IDO. In the EAE animal model, systemic rfNSCs-IDO injections resulted in significant local immune suppression in the cervical lymph nodes and CNS, evidenced by a reduction in the number of activated T lymphocytes and an increase in regulatory T cell numbers, which induced significantly fewer clinical symptoms and faster recovery. In contrast, rfNSCs-Cont failed to reduce symptoms in the EAE animal models, although they showed local immune suppression, which was significantly less than that in rfNSCs-IDO. Taken together, IDO expression in NSCs synergistically potentiates the immune suppression activities of NSCs and could be applicable for the development of therapeutic modalities against various neurodegenerative diseases.

Repurposing the anti-malarial drug artesunate as a novel therapeutic agent for metastatic renal cell carcinoma due to its attenuation of tumor growth, metastasis, and angiogenesis.

Despite advances in the development of molecularly targeted therapies, metastatic renal cell carcinoma (RCC) is still incurable. Artesunate (ART), a well-known anti-malarial drug with low toxicity, exhibits highly selective anti-tumor actions against various tumors through generation of cytotoxic carbon-centered free radical in the presence of free iron. However, the therapeutic efficacy of ART against metastatic RCC has not yet been fully elucidated. In the analysis on a dataset from The Cancer Genome Atlas (TCGA) (n = 469) and a tissue microarray set from Samsung Medical Center (n = 119) from a cohort of patients with clear cell RCC (ccRCC), up-regulation of transferrin receptor 1 (TfR1), which is a well-known predictive marker for ART, was correlated with the presence of distant metastasis and an unfavorable prognosis. Moreover, ART exerted potent selective cytotoxicity against human RCC cell lines (Caki-1, 786-O, and SN12C-GFP-SRLu2) and sensitized these cells to sorafenib in vitro, and the extent of ART cytotoxicity correlated with TfR1 expression. ART-mediated growth inhibition of human RCC cell lines was shown to result from the induction of cell cycle arrest at the G2/M phase and oncosis-like cell death. Furthermore, ART inhibited cell clonogenicity and invasion of human RCC cells and anti-angiogenic effects in vitro in a dose-dependent manner. Consistent with these in vitro data, anti-tumor, anti-metastatic and anti-angiogenic effects of ART were also validated in human 786-O xenografts. Taken together, ART is a promising novel candidate for treating human RCC, either alone or in combination with other therapies.

Overexpression of microRNA-95-3p suppresses brain metastasis of lung adenocarcinoma through downregulation of cyclin D1.

Despite great efforts to improve survival rates, the prognosis of lung cancer patients is still very poor, mainly due to high invasiveness. We developed brain metastatic PC14PE6/LvBr4 cells through intracardiac injection of lung adenocarcinoma PC14PE6 cells. Western blot and RT-qPCR analyses revealed that PC14PE6/LvBr4 cells had mesenchymal characteristics and higher invasiveness than PC14PE6 cells. We found that cyclin D1 was upregulated, miR-95-3p was inversely downregulated, and pri-miR-95 and its host gene, ABLIM2, were consistently decreased in PC14PE6/LvBr4 cells. MiR-95-3p suppressed cyclin D1 expression through direct binding to the 3' UTR of cyclin D1 mRNA and suppressed invasiveness, proliferation, and clonogenicity of PC14PE6/LvBr4 cells. Ectopic cyclin D1 reversed miR-95-3p-mediated inhibition of invasiveness and clonogenicity, demonstrating cyclin D1 downregulation is involved in function of miR-95-3p. Using bioluminescence imaging, we found that miR-95-3p suppressed orthotopic tumorigenicity and brain metastasis in vivo and increased overall survival and brain metastasis-free survival. Consistent with in vitro metastatic cells, the levels of miR-95-3p, pri-miR-95, and ABLIM2 mRNA were decreased in brain metastatic tissues compared with lung cancer tissues and higher cyclin D1 expression was involved in poor prognosis. Taken together, our results demonstrate that miR-95-3p is a potential therapeutic target for brain metastasis of lung adenocarcinoma cells.

Patient-derived xenografts from non-small cell lung cancer brain metastases are valuable translational platforms for the development of personalized targeted therapy.

PURPOSE: The increasing prevalence of distant metastases from non-small cell lung cancer (NSCLC) indicates an urgent need for novel therapeutic modalities. Brain metastasis is particularly common in NSCLC, with severe adverse effects on clinical prognosis. Although the molecular heterogeneity of NSCLC and availability of various targeted agents suggest personalized therapeutic approaches for such brain metastases, further development of appropriate preclinical models is needed to validate the strategies. EXPERIMENTAL DESIGN: We established patient-derived xenografts (PDX) using NSCLC brain metastasis surgical samples and elucidated their possible preclinical and clinical implications for personalized treatment. RESULTS: NSCLC brain metastases (n = 34) showed a significantly higher successful PDX establishment rate than primary specimens (n = 64; 74% vs. 23%). PDXs derived from NSCLC brain metastases recapitulated the pathologic, genetic, and functional properties of corresponding parental tumors. Furthermore, tumor spheres established in vitro from the xenografts under serum-free conditions maintained their in vivo brain metastatic potential. Differential phenotypic and molecular responses to 20 targeted agents could subsequently be screened in vitro using these NSCLC PDXs derived from brain metastases. Although PDX establishment from primary NSCLCs was significantly influenced by histologic subtype, clinical aggressiveness, and genetic alteration status, the brain metastases exhibited consistently adequate in vivo tumor take rate and in vitro tumor sphere formation capacity, regardless of clinical and molecular conditions. CONCLUSIONS: Therefore, PDXs from NSCLC brain metastases may better represent the heterogeneous advanced NSCLC population and could be utilized as preclinical models to meet unmet clinical needs such as drug screening for personalized treatments.

Tpl2 induces castration resistant prostate cancer progression and metastasis.

Progression to metastatic castration resistant prostate cancer (CRPC) is the major lethal pathway of prostate cancer (PC). Herein, we demonstrated that tumor progression locus 2 (Tpl2) kinase is the fundamental molecule provoking progression and metastasis of CRPC. Tpl2 upregulates CXCR4 and focal adhesion kinase (FAK) to activate CXCL12/CXCR4 and FAK/Akt signalling pathway. Consequently, epithelial-mesenchymal transition (EMT) and stemness of androgen depletion independent (ADI) PC cells are induced, which is dependent on the kinase activity of Tpl2. In vitro, proliferation, clonogenicity, migration, invasion and chemoresistance of ADI PC cells were enhanced by Tpl2. In vivo, Tpl2 overexpression and downregulation showed significant stimulatory and inhibitory effects on tumorigenic and metastatic potential of ADI PC cells, respectively. Moreover, the prognostic effects of Tpl2 and expressional correlation between Tpl2 and EMT-related molecules/CXCR4 were validated in clinical PC databases. Since Tpl2 exerts metastatic progression promoting activities in CRPC, Tpl2 could serve as a novel therapeutic target for metastatic CRPC.

Comparative Analysis of Various Photoelectrodes for Dye-Sensitized Solar Cells.

We prepared nanopastes containing various additives such as acetylene black (AB paste), 3,5-dinitrosalicylic acid (NSA paste) and SiC2 particles (SO paste), and these nanopastes were employed in preparation of photoelectrodes for dye sensitized solar cells (DSSCs). Photoelectrodes of AB, NSA and SO paste have characteristics of large pore size, superior interconnection among particles, and scattering due to spherical particle shape, respectively. Photovoltaic parameters of cells formed from the pastes were compared with cell formed from the paste without additive. Among the pastes, AB paste exhibited the best cell efficiency improvement of 9.647%. NSA paste also exhibited considerable cell efficiency improvement without much deleterious impact on transparency. The advantages and disadvantages of each nanopastes were analysed for the commercialization of DSSCs.

Comparative study of various growth factors and cytokines on type I collagen and hyaluronan production in human dermal fibroblasts.

BACKGROUND: Dermal fibroblast is a primary cell type responsible for synthesis and remodeling of extracellular matrix in human skin. Type I collagen and hyaluronan are main components that have roles in skin fibrosis, wound healing, tissue remodeling as well as skin aging. Several studies have reported cytokine-dependent changes in collagen expression or hyaluronan production; however, the cytokines' effect was controversial in human dermal fibroblasts. AIMS: To clarify the role of various growth factors, cytokines or chemokines on the production of interstitial type I collagen and hyaluronan in dermal fibroblasts. METHODS: We confirmed the presence of various corresponding receptors and assessed the effects of 33 human recombinants on the production of type I collagen and hyaluronan using the assay system in dermal fibroblasts. RESULTS: Platelet-derived growth factor (PDGF)-AA, PDGF-BB, epidermal growth factor (EGF), transforming growth factor (TGF)-ß1, MCP-1, IP-10, interleukin (IL)-1α, IL-1ß, and IL-15 were effective on both type I collagen and hyaluronan production, as compared with no stimulated control. On the other hand, IL-10 and IFN- α caused a significant decrease in type I collagen production, and IL-8 and GM-CSF caused a decrease in hyaluronan production compared with no cytokine-treated control. Interestingly, some chemokines, such as MCP-1 (CCL2), RANTES (CCL5), eotaxin-2 (CCL24), IP-10 (CXCL10), or fractalkine (CX3CL1) significantly induced the type I collagen or hyaluronan production. CONCLUSIONS: Various growth factors and cytokines on the regulation of type I collagen and hyaluronan in human dermal skin probably function as key factors in skin remodeling and skin aging. Our profile may help to apply to cosmeceutical area maintaining as young skin through the increase in extracellular matrix.

Ubiquilin 1 interacts with Orai1 to regulate calcium mobilization.

Store-operated calcium entry (SOCE) channels composed of Stim and Orai proteins play a critical role in diverse biological processes. Upon endoplasmic reticulum (ER)-mediated calcium (Ca(2+)) depletion, Stim proteins oligomerize with Orai to initiate Ca(2+) influx across the plasma membrane. The ubiquitin-like (UBL) and ubiquitin-associated (UBA) domains of ubiquilin 1 are involved in the degradation of presenilin and polyglutamine proteins. Through screening of Orai1 interaction partner(s) that might have an effect on SOCE, ubiquilin 1 was identified as a target of Orai1. However, the UBL and UBA domains of ubiquilin 1 were dispensable for this interaction. Additionally, ubiquilin 1 and Orai1 colocalized in the cytosolic compartment. Ubiquilin 1 increased the ubiquitination of Orai1, resulting in the formation of a high-molecular-weight form. MG132, a proteasome inhibitor, failed to block the degradation of Orai1, whereas bafilomycin A, a lysosome inhibitor, prevented Orai1 degradation. Confocal microscopy studies demonstrated that a fraction of Orai1 colocalized with ubiquilin 1 and the autophagosomal marker LC3. Because Orai1 is a constituent of SOCE, we determined the effect of ubiquilin 1 on Orai1-mediated Ca(2+) influx. As we expected, intracellular Ca(2+) mobilization, a process normally potentiated by Orai1, was downregulated by ubiquilin 1. Taken together, these findings suggest that ubiquilin 1 downregulates intracellular Ca(2+) mobilization and its downstream signaling by promoting the ubiquitination and lysosomal degradation of Orai1.

Influence of parthenogenetic activation on nuclear maturation of canine oocytes.

This study was designed to evaluate the nuclear maturation and maturation promoting factor (MPF) level at different maturation times, and the effect of parthenogenetic activation on nuclear maturation in canine oocytes. Cumulus-oocyte complexes (COCs) were matured in TCM-199 supplemented with 10% fetal bovine serum, hormones, 0.57 mM cysteine, and 10 ng/ml epidermal growth factor for 72 hr at 38.5 degrees C. In Experiment 1, COCs at 0, 24, 48 and 72 hr of culture were assessed for nuclear maturation and MPF levels using histone H1 kinase activity assay. A significantly higher rate of oocytes at 72 hr than 0, 24 and 48 hr of culture developed to metaphase I-anaphase I and metaphase II. Relative abundance of histone H1 kinase activity of oocytes matured for 48 hr increased to ~1.5 x, with a marked increase to approximately 2.5 x for 72 hr, significantly higher than others. In Experiment 2, oocytes matured for 48 hr were parthenogenetically activated with 5 microm ionomycin for 5 min (Group 1) and followed by 10 microg/ml cycloheximide for 3 hr (Group 2), or no treatment (Control). Oocytes were then cultured for 24 hr and assessed for nuclear maturation. A significantly higher rate of oocytes in Group 1 developed to metaphase II than in Group 2 and the control. These results indicated that ionomycin treatment at 48 hr of in vitro maturation had a positive influence on oocyte progression to the metaphase II stage.

Effect of alpha-tocopherol supplementation during boar semen cryopreservation on sperm characteristics and expression of apoptosis related genes.

Boar semen is extremely vulnerable to cold shock and sensitive to peroxidative damage due to high content of unsaturated fatty acids in the phospholipids of the plasma membrane and the relatively low antioxidant capacity of seminal plasma. The present study evaluated the influence of alpha-tocopherol supplementation at various concentrations in the boar semen extender during cryopreservation on post-thawed sperm motility characteristics (total sperm motility, MOT; local motility, LCM; curvilinear velocity, VCL; straight linear velocity, VSL; and average path velocity, VAP), sperm qualities (viability, acrosomal integrity and apoptosis), expression of stress protein (HSP70), and the expression of pro-apoptotic (Bax and Bak) and anti-apoptotic (Bcl-2l and Bcl-xl) genes. Semen collected from 10 Duroc boars was cryopreserved in lactose-egg yolk buffer supplemented with various concentrations of alpha-tocopherol (0, 100, 200, 400, 600 and 800 microM) using the straw-freezing procedure and stored at -196 degrees C for a minimum period of one month. In frozen-thawed groups, sperm motility was significantly (P<0.05) lower than that of fresh sperm. In fresh sperm, HSP70 immunoreactivity expression was observed in the equatorial region, but in frozen-thawed groups, expressions were mostly observed in the sperm head. Higher apoptosis rates were observed in 600 and 800 microM alpha-tocopherol supplemented frozen-thawed groups. In alpha-tocopherol supplemented frozen-thawed groups immediately after thawing, the expression was similar to that of fresh group. But after incubation at 37 degrees C for 3h, the expression in 200 and 800 microM alpha-tocopherol supplemented groups was higher than that of others. Expression of pro-apoptotic genes was significantly higher and anti-apoptotic genes was significantly (P<0.01) lower in alpha-tocopherol supplemented frozen-thawed groups compared to fresh sperm group. In conclusion, alpha-tocopherol, supplemented at 200 microM concentration in boar semen extender during cryopreservation had a positive effect on post-thawed sperm survivability.