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961.
Hiroshi Yamamoto Toshiaki Endo Tamotsu Kiya Taeko Goto Satoru Sagae Eiki Ito Hiroshi Watanabe Ryuichi Kudo 《Prostaglandins & other lipid mediators》1995,50(4)
In rat luteal cells labeled with (3H]oleic acid, PGF2α-stimulated phospholipase D (PLD) activation was investigated. The PLD activity was detected by measuring the accumulation of [3H]phosphatidylethanol (PtdEt) in the presence of ethanol. PGF2α stimulated PtdEt accumulation at concentrations of more than 100 nM in the presence of ethanol. However, PtdEt accumulation did not change in the absence of ethanol. PGF2α (1 μM) increased PtdEt accumulation after 1 min, and the accumulation reached a plateau by 2–3 min. These results indicate that PGF2α activates PLD in rat luteal cells. U-73122, a phospholipase C (PLC) inhibitor, and staurosporine, a protein kinase C (PKC) inhibitor, did not inhibit PGF2α-stimulated [3H]PtdEt accumulation. These results suggest that PGF2α-induced PLD activation is different from PLC-PKC systems. We reported previously that PGF2α stimulated the release of arachidonic acid. The effects of indomethacin, nordihydroguaiaretic acid (NDGA), and 5,8,11,14-eicosatetraynoic acid (ETYA), inhibitors of arachidonic acid metabolism, on PGF2α-stimulated PtdEt accumulation were examined. Pretreatment with indomethacin enhanced PGF2α-induced PtdEt accumulation. In contrast, pretreatment with NDGA and ETYA inhibited PGF2α-induced PtdEt accumulation. It is suggested that PGF2α-stimulated PLD activation is mediated via lipoxygenase products. 相似文献
962.
963.
Josephe Archie Honorat Makoto Kinoshita Tatsusada Okuno Kazushiro Takata Toru Koda Satoru Tada Takashi Shirakura Harutoshi Fujimura Hideki Mochizuki Saburo Sakoda Yuji Nakatsuji 《PloS one》2013,8(8)
Objectives
Oxidative stress plays an important role in the pathogenesis of multiple sclerosis (MS). Though reactive oxygen species (ROS) are produced by various mechanisms, xanthine oxidase (XO) is a major enzyme generating ROS in the context of inflammation. The objectives of this study were to investigate the involvement of XO in the pathogenesis of MS and to develop a potent new therapy for MS based on the inhibition of ROS.Methods
XO were assessed in a model of MS: experimental autoimmune encephalomyelitis (EAE). The contribution of XO-generated ROS to the pathogenesis of EAE was assessed by treating EAE mice with a novel XO inhibitor, febuxostat. The efficacy of febuxostat was also examined in in vitro studies.Results
We showed for the first time that the expression and the activity of XO were increased dramatically within the central nervous system of EAE mice as compared to naïve mice. Furthermore, prophylactic administration of febuxostat, a XO inhibitor, markedly reduced the clinical signs of EAE. Both in vivo and in vitro studies showed infiltrating macrophages and microglia as the major sources of excess XO production, and febuxostat significantly suppressed ROS generation from these cells. Inflammatory cellular infiltration and glial activation in the spinal cord of EAE mice were inhibited by the treatment with febuxostat. Importantly, therapeutic efficacy was observed not only in mice with relapsing-remitting EAE but also in mice with secondary progressive EAE by preventing axonal loss and demyelination.Conclusion
These results highlight the implication of XO in EAE pathogenesis and suggest XO as a target for MS treatment and febuxostat as a promising therapeutic option for MS neuropathology. 相似文献964.
Masafumi Toyoshima Yoshinori Tanaka Mitsuyo Matumoto Miyuki Yamazaki Satoru Nagase Kazuo Sugamura Nobuo Yaegashi 《Luminescence》2009,24(5):324-331
In order to facilitate the discovery and investigation of anti‐cancer therapeutics under physiological conditions, we have engineered the ovarian cancer cell line, HM‐1/luc, in mice. This cell stably expresses firefly luciferase and produces light that can be detected using an in vivo imaging system (IVIS). Parental HM‐1 cells cause severe carcinomatous peritonitis to B6C3F1 mice, but not to C57BL6 mice. Established HM‐1/luc cells showed pathologically similar findings to HM‐1 cells. HM‐1/luc cells were injected into the peritoneal cavity of B6C3F1 mice and IVIS 2000 was conducted weekly after inoculation to monitor intra‐peritoneal tumor growth. The mice were divided into three groups: non‐CDDP‐treated (control) and CDDP‐treated (0.2 and 0.4 mg). A disease‐suppressive effect of the CDDP was reflected by the significantly prolonged survival of the CDDP‐treated mice (control 23 ± 1.9 days, CDDP 0.2 mg 29.6 ± 2.9 days; p < 0.05); the total photon and area of flux were decreased. The optical imaging of intraperitoneal tumors via in vivo bioluminescence is effective for noninvasive monitoring and semi‐quantitative analysis. Our syngeneic mouse model has the relevant clinical features of ovarian cancer, which makes it a useful model for developing new ovarian cancer therapies. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
965.
Midori Okamura Keigyou Yoh Masami Ojima Naoki Morito Satoru Takahashi 《Experimental Animals》2014,63(2):133-140
Ulcerative colitis (UC) is an inflammatory bowel disease, and its pathogenesis includes
genetic, environmental, and immunological factors, such as T helper cells and their
secreted cytokines. T helper cells are classified as Th1, Th2, and Th17 cells. However, it
is unclear which T helper cells are important in UC. Dextran sulfate sodium (DSS)-induced
colitis is a commonly used model of UC. In this study, we induced DSS colitis in Th1
dominant (T-bet transgenic (Tg)) mice, Th2 dominant (GATA-3 Tg) mice, and Th17 dominant
(RORγt Tg) mice to elucidate the roles of T helper cell in DSS colitis. The results showed
that GATA-3 Tg mice developed the most severe DSS colitis compared with the other groups.
GATA-3 Tg mice showed a significant decreased in weight from day 1 to day 7, and an
increased high score for the disease activity index compared with the other groups.
Furthermore, GATA-3 Tg mice developed many ulcers in the colon, and many neutrophils and
macrophages were detected on day 4 after DSS treatment. Measurement of GATA-3-induced
cytokines demonstrated that IL-13 was highly expressed in the colon from DSS-induced
GATA-3 Tg mice. In conclusion, GATA-3 overexpression in T-cells and IL-13 might play
important roles in the development of DSS colitis. 相似文献
966.
Yuh Shiwa Hiroaki Yanase Yuu Hirose Shohei Satomi Tomoko Araya-Kojima Satoru Watanabe Takeshi Zendo Taku Chibazakura Mariko Shimizu-Kadota Hirofumi Yoshikawa Kenji Sonomoto 《DNA research》2014,21(4):369-377
Enterococcus mundtii QU 25, a non-dairy bacterial strain of ovine faecal origin, can ferment both cellobiose and xylose to produce l-lactic acid. The use of this strain is highly desirable for economical l-lactate production from renewable biomass substrates. Genome sequence determination is necessary for the genetic improvement of this strain. We report the complete genome sequence of strain QU 25, primarily determined using Pacific Biosciences sequencing technology. The E. mundtii QU 25 genome comprises a 3 022 186-bp single circular chromosome (GC content, 38.6%) and five circular plasmids: pQY182, pQY082, pQY039, pQY024, and pQY003. In all, 2900 protein-coding sequences, 63 tRNA genes, and 6 rRNA operons were predicted in the QU 25 chromosome. Plasmid pQY024 harbours genes for mundticin production. We found that strain QU 25 produces a bacteriocin, suggesting that mundticin-encoded genes on plasmid pQY024 were functional. For lactic acid fermentation, two gene clusters were identified—one involved in the initial metabolism of xylose and uptake of pentose and the second containing genes for the pentose phosphate pathway and uptake of related sugars. This is the first complete genome sequence of an E. mundtii strain. The data provide insights into lactate production in this bacterium and its evolution among enterococci. 相似文献
967.
Hajime Honma Makoto Hirai Shota Nakamura Hassan Hakimi Shin-ichiro Kawazu Nirianne M.Q. Palacpac Hajime Hisaeda Hiroyuki Matsuoka Satoru Kawai Hiroyoshi Endo Teruo Yasunaga Jun Ohashi Toshihiro Mita Toshihiro Horii Mitsuru Furusawa Kazuyuki Tanabe 《DNA research》2014,21(4):439-446
Plasmodium falciparum malaria imposes a serious public health concern throughout the tropics. Although genetic tools are principally important to fully investigate malaria parasites, currently available forward and reverse tools are fairly limited. It is expected that parasites with a high mutation rate can readily acquire novel phenotypes/traits; however, they remain an untapped tool for malaria biology. Here, we generated a mutator malaria parasite (hereinafter called a ‘malaria mutator’), using site-directed mutagenesis and gene transfection techniques. A mutator Plasmodium berghei line with a defective proofreading 3′ → 5′ exonuclease activity in DNA polymerase δ (referred to as PbMut) and a control P. berghei line with wild-type DNA polymerase δ (referred to as PbCtl) were maintained by weekly passage in ddY mice for 122 weeks. High-throughput genome sequencing analysis revealed that two PbMut lines had 175–178 mutations and a 86- to 90-fold higher mutation rate than that of a PbCtl line. PbMut, PbCtl, and their parent strain, PbWT, showed similar course of infection. Interestingly, PbMut lost the ability to form gametocytes during serial passages. We believe that the malaria mutator system could provide a novel and useful tool to investigate malaria biology. 相似文献
968.
Kanae Nakamura Tsunao Kishida Akika Ejima Riho Tateyama Satoru Morishita Tomoji Ono Michiaki Murakoshi Keikichi Sugiyama Hoyoku Nishino Osam Mazda 《Biometals》2018,31(3):415-424
Lactoferrin (LF) is a multifunctional protein in mammalian milk. We previously reported that enteric-coated bovine LF reduced the visceral fat in a double-blind clinical study. We further demonstrated that bovine LF (bLF) inhibited adipogenesis and promoted lipolysis in white adipocytes, but the effect of bLF on brown adipocytes has not been clarified. In this study, we investigated the effects of bLF on energy expenditure and cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) signaling pathway using human reprogrammed brown adipocytes generated by gene transduction. bLF at concentrations of ≥?100 μg/mL significantly increased uncoupling protein 1 (UCP1) mRNA levels, with the maximum value observed 4 h after bLF addition. At the same time point, bLF stimulation also significantly increased oxygen consumption. Signaling pathway analysis revealed rapid increases of intracellular cAMP and cAMP response element-binding protein (CREB) phosphorylation levels beginning 5 min after bLF addition. The mRNA levels of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) were also significantly increased after 1 h of bLF stimulation. H-89, a specific PKA inhibitor, abrogated bLF-induced UCP1 gene expression. Moreover, receptor-associated protein (Rap), an antagonist of low-density lipoprotein receptor-related protein 1 (LRP1), significantly reduced bLF-induced UCP1 gene expression in a dose-dependent manner. These results suggest that bLF promotes UCP1 gene expression in brown adipocytes through the cAMP-PKA signaling pathway via the LRP1 receptor, leading to increased energy expenditure. 相似文献
969.
Read-depths (RDs) are frequently used in identifying structural variants (SVs) from sequencing data. For existing RD-based SV callers, it is difficult for them to determine breakpoints in single-nucleotide resolution due to the noisiness of RD data and the bin-based calculation. In this paper, we propose to use the deep segmentation model UNet to learn base-wise RD patterns surrounding breakpoints of known SVs. We integrate model predictions with an RD-based SV caller to enhance breakpoints in single-nucleotide resolution. We show that UNet can be trained with a small amount of data and can be applied both in-sample and cross-sample. An enhancement pipeline named RDBKE significantly increases the number of SVs with more precise breakpoints on simulated and real data. The source code of RDBKE is freely available at https://github.com/yaozhong/deepIntraSV. 相似文献
970.
MicroRNAs (miRNAs) are endogenous non-coding small RNAs that have emerged as one of the central players of gene expression regulation. Endothelial cell apoptosis plays a fundamental role in the development of atherosclerosis. This study was designed to determine the effect of miR-513a-5p on apoptosis of human umbilical vein endothelial cells (HUVECs). HUVECs were treated with tumour necrosis factor-α (TNF-α) and lipopolysaccharide (LPS) and miR-513a-5p expression levels were determined. MiR-513a-5p target gene indentification, validation, and signalling pathways were investigated. Treatment of HUVECs with TNF-α and LPS up-regulated miR-513a-5p expressions more than 2-fold compared to control (P < 0.05). Inhibition of miR-513a-5p by antisense (AS) miR-513a-5p reversed TNF-α and LPS induced apoptosis (P < 0.01). Transfection of HUVECs with miR-513a-5p mimics also induced apoptosis (P < 0.01). Treatment of HUVECs with TNF-α and LPS attenuated X-linked inhibitor of apoptosis (XIAP) while increased caspase-3 expression, poly ADP-ribose polymerase (PARP) cleavage, and p53 expression. These effects were reversed by inhibition of miR-513a-5p. Of those miR-513a-5p candidate target genes, we identified and validated XIAP as a miR-513a-5p target gene. Targeting of the XIAP 3′-untranslated region by miR-513a-5p using luciferase reporter assay resulted in attenuated luciferase activity. Transfection of HUVECs with AS miR-513a-5p increased XIAP protein expression while miR-513a-5p mimics attenuated XIAP expression. These results together suggest that miR-513a-5p mediates TNF-α and LPS induced apoptosis via downregulation of XIAP in HUVECs. 相似文献