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131.
Huifang Hao Yutaka Maeda Takuya Fukazawa Tomoki Yamatsuji Munenori Takaoka Xiao-Hong Bao Junji Matsuoka Tatsuo Okui Tsuyoshi Shimo Nagio Takigawa Yasuko Tomono Motowo Nakajima Iris M. Fink-Baldauf Sandra Nelson William Seibel Ruben Papoian Jeffrey A. Whitsett Yoshio Naomoto 《PloS one》2013,8(8)
Midkine (MDK) is a heparin-binding growth factor that is highly expressed in many malignant tumors, including lung cancers. MDK activates the PI3K pathway and induces anti-apoptotic activity, in turn enhancing the survival of tumors. Therefore, the inhibition of MDK is considered a potential strategy for cancer therapy. In the present study, we demonstrate a novel small molecule compound (iMDK) that targets MDK. iMDK inhibited the cell growth of MDK-positive H441 lung adenocarcinoma cells that harbor an oncogenic KRAS mutation and H520 squamous cell lung cancer cells, both of which are types of untreatable lung cancer. However, iMDK did not reduce the cell viability of MDK-negative A549 lung adenocarcinoma cells or normal human lung fibroblast (NHLF) cells indicating its specificity. iMDK suppressed the endogenous expression of MDK but not that of other growth factors such as PTN or VEGF. iMDK suppressed the growth of H441 cells by inhibiting the PI3K pathway and inducing apoptosis. Systemic administration of iMDK significantly inhibited tumor growth in a xenograft mouse model in vivo. Inhibition of MDK with iMDK provides a potential therapeutic approach for the treatment of lung cancers that are driven by MDK. 相似文献
132.
Satoshi Mizuno Soichi Ogishima Kazuyuki Kitatani Masataka Kikuchi Hiroshi Tanaka Nobuo Yaegashi Jun Nakaya 《PloS one》2016,11(2)
Alzheimer’s disease (AD) is the most common cause of senile dementia. Many inflammatory factors such as amyloid-β and pro-inflammatory cytokines are known to contribute to the inflammatory response in the AD brain. Sphingolipids are widely known to have roles in the pathogenesis of inflammatory diseases, where the precise roles for sphingolipids in inflammation-associated pathogenesis of AD are not well understood. Here we performed a network analysis to clarify the importance of sphingolipids and to model relationships among inflammatory factors and sphingolipids in AD. In this study, we have updated sphingolipid signaling and metabolic cascades in a map of AD signaling networks that we named “AlzPathway,” a comprehensive knowledge repository of signaling pathways in AD. Our network analysis of the updated AlzPathway indicates that the pathways related to ceramide are one of the primary pathways and that ceramide is one of the important players in the pathogenesis of AD. The results of our analysis suggest the following two prospects about inflammation in AD: (1) ceramide could play important roles in both inflammatory and anti-inflammatory pathways of AD, and (2) several factors such as Sphingomyelinase and Siglec-11 may be associated with ceramide related inflammation and anti-inflammation pathways in AD. In this study, network analysis of comprehensive knowledge repository reveals a dual role for ceramide in AD. This result provides a clue to clarify sphingolipids related inflammatory and anti-inflammatory pathways in AD. 相似文献
133.
134.
Keiko Yasuma Jun-ichirou Yasunaga Keiko Takemoto Kenji Sugata Yuichi Mitobe Norihiro Takenouchi Masanori Nakagawa Yutaka Suzuki Masao Matsuoka 《PLoS pathogens》2016,12(1)
Human T-cell leukemia virus type 1 (HTLV-1) infects CD4+ T cells and induces proliferation of infected cells in vivo, which leads to the onset of adult T-cell leukemia (ATL) in some infected individuals. The HTLV-1 bZIP factor (HBZ) gene, which is encoded in the minus strand of HTLV-1, plays critical roles in pathogenesis. In this study, RNA-seq and ChIP-seq analyses using HBZ transduced T cells revealed that HBZ upregulates the expression and promoter acetylation levels of a co-inhibitory molecule, T cell immunoglobulin and ITIM domain (TIGIT), in addition to those of regulatory T cells related genes, Foxp3 and Ccr4. TIGIT was expressed on CD4+ T cells from HBZ-transgenic (HBZ-Tg) mice, and on ATL cells and HTLV-1 infected CD4+ T cells of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in vivo. Expression of Blimp1 and IL-10 was upregulated in TIGIT+CD4+ cells of HBZ-Tg mice compared with TIGIT-CD4+ T cells, suggesting the correlation between TIGIT expression and IL-10 production. When CD4+ T cells from HBZ-Tg mice were stimulated with TIGIT’s ligand, CD155, their production of the inhibitory cytokine IL-10 was enhanced. Furthermore, dendritic cells from HBZ-Tg mice produced high levels of IL-10 after stimulation. These data suggest that HBZ alters immune system to suppressive state via TIGIT and IL-10. Importantly, TIGIT suppressed T-cell responses to another HTLV-1 virus protein, Tax, in vitro. Blocking of TIGIT and PD-1 slightly increased anti-Tax T-cell activity in some HAM/TSP patients. These results suggest that HBZ-induced TIGIT on HTLV-1 infected cells impairs T-cell responses to viral antigens. This study shows that HBZ-induced TIGIT plays a pivotal role in attenuating host immune responses and shaping a microenvironment favorable to HTLV-1. 相似文献
135.
Mikako Saito Asako Kaneda Hajime Shigeto Nobuaki Hanata Keiko Otokuni Hideaki Matsuoka 《Cytotechnology》2016,68(4):987-998
In order to produce insulin-secreting cells with a high value of glucose-stimulated insulin secretion (GSIS) from mouse embryonic stem cells, we have developed an optimized 5-stage protocol by referring to culture conditions so far reported elsewhere. This protocol is characterized by 4 points: (1) use of an activin-free medium in the first stage, (2) use of gelatin/fibronectin coated culture dishes in 1–4 stages throughout, (3) removal of undifferentiated cells by cell sorter at the end of 4th stage, and (4) sedimental culture in the 5th stage. GSIS value of the produced cells reached 2.4, that was at a higher rank of those so far reported. The produced cells were transplanted in diabetes model mice but no remedy effect was observed. Then transplantation was conducted in pre-diabetes model mice, in which GSIS was impaired without affecting insulin producing function. The transplantation of 5 × 106 cells resulted in a marked improvement of glucose tolerance within 20 days. This effect decreased but was still observed at 120 days post-transplantation. This demonstrates the feasibility of the novel optimized protocol. 相似文献
136.
Takashi Yazawa Yoshitaka Imamichi Koh‐ichi Yuhki Junsuke Uwada Daisuke Mikami Masayuki Shimada Kaoru Miyamoto Takeshi Kitano Satoru Takahashi Toshio Sekiguchi Nobuo Suzuki Md. Rafiqul Islam Khan Fumitaka Ushikubi Akihiro Umezawa Takanobu Taniguchi 《Molecular reproduction and development》2019,86(7):786-797
137.
Kamichika Hayashi Takeshi Onda Hirona Honda Natsuo Ozawa Hitoshi Ohata Nobuo Takano Takahiko Shibahara 《Biochemistry and Biophysics Reports》2019
No effective, reliable treatment for stomatitis associated with cancer therapy has been established. This study focused on the its effectiveness of ozone nano-bubble water (ONBW) for the treatment of chemotherapy-induced stomatitis. Oral mucositis was induced in 14-week-old male Sprague-Dawley rats (N = 21). The animals were randomly divided into 3 groups: 7 without treatment (control); 7 treated with physiological salt solution (saline); and 7 treated with ONBW. Animals were weighed on Days 7, 9, 11, and 16. Stomatitis grade evaluation and bacterial count measurements were performed before rinsing in all animals 3, 5, and 10 days after acetic acid irritation (Days 9, 11, and 17 respectively). Weight loss after stomatitis creation was observed in all groups, with significant differences between the control and ONBW groups and between the saline and ONBW groups on Day 16. The stomatitis grade did not worsen during the experimental period in any group, with the lowest grades in the ONBW group on Days 11 and 16. Significant differences were identified between the control and ONBW groups and between the saline and ONBW groups on Days 11 and 16. Oral bacterial counts tended to decrease over time in all three groups, with the greatest decrease in the ONBW group, followed by the saline group. The decrease in the bacterial count was steepest in the ONBW group. Rinsing out the oral cavity with ONBW decreased bacterial counts and encouraged the healing of oral chemotherapy-induced stomatitis. ONBW may be an effective treatment for chemotherapy-induced stomatitis. 相似文献
138.
Uemoto Y Suzuki S Terada N Ohno N Ohno S Yamanaka S Komada M 《The Journal of biological chemistry》2007,282(9):6548-6555
At axon initial segments and nodes of Ranvier in neurons, the spectrin membrane skeleton plays roles in physically stabilizing the plasma membrane integrity and in clustering voltage-gated sodium channels for proper conduction of the action potential. betaIV-Spectrin, an essential component of the membrane skeleton at these sites, has an N-terminal-truncated isoform, Sigma6, which is expressed at much higher levels than the full-length isoform Sigma1. To investigate the role of betaIV-spectrin Sigma6, we generated Sigma1-deficient mice with a normal level of Sigma6 expression (Sigma1(-/-) mice), and compared their phenotypes with those of previously generated mice lacking both Sigma1 and Sigma6(Sigma1Sigma6(-/-) mice). The gross neurological defects observed in Sigma1Sigma6(-/-) mice, such as hindleg contraction, were apparently ameliorated in Sigma1(-/-) mice. At cellular levels, Sigma1Sigma6(-/-) and Sigma1(-/-) neurons similarly exhibited waving and swelling of the plasma membrane at axon initial segments and nodes of Ranvier. By contrast, the levels of ankyrin G and voltage-gated sodium channels at these sites, which are significantly reduced in Sigma1Sigma6(-/-) mice, were substantially recovered in Sigma1(-/-) mice. We conclude that the truncated betaIV-spectrin isoform Sigma6 plays a specific role in clustering voltage-gated sodium channels, whereas it is dispensable for membrane stabilization at axon initial segments and nodes of Ranvier. 相似文献
139.
This protocol details a method for monitoring glucose uptake into single, living mammalian cells using a fluorescent D-glucose derivative, 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NBDG), as a tracer. The specifically designed chamber and superfusion system for evaluating 2-NBDG uptake into cells in real time can be combined with other fluorescent methods such as Ca2+ imaging and the subsequent immunofluorescent classification of cells exhibiting divergent 2-NBDG uptake. The whole protocol, including immunocytochemistry, can be completed within 2 d (except for cell culture). The procedure for 2-NBDG synthesis is also presented. 相似文献
140.
Journal of Ichthyology - The Serranidae are well known for protogynous sex change. The red-belted anthias Pseudanthias rubrizonatus inhabits Kagoshima Bay. We aimed to estimate the body size and... 相似文献