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81.
Nanami Senoo Noriyuki Miyoshi Naoko Goto-Inoue Kimiko Minami Ryoji Yoshimura Akihito Morita Naoki Sawada Junichiro Matsuda Yoshihiro Ogawa Mitsutoshi Setou Yasutomi Kamei Shinji Miura 《Journal of lipid research》2015,56(12):2286-2296
Exercise training influences phospholipid fatty acid composition in skeletal muscle and these changes are associated with physiological phenotypes; however, the molecular mechanism of this influence on compositional changes is poorly understood. Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a nuclear receptor coactivator, promotes mitochondrial biogenesis, the fiber-type switch to oxidative fibers, and angiogenesis in skeletal muscle. Because exercise training induces these adaptations, together with increased PGC-1α, PGC-1α may contribute to the exercise-mediated change in phospholipid fatty acid composition. To determine the role of PGC-1α, we performed lipidomic analyses of skeletal muscle from genetically modified mice that overexpress PGC-1α in skeletal muscle or that carry KO alleles of PGC-1α. We found that PGC-1α affected lipid profiles in skeletal muscle and increased several phospholipid species in glycolytic muscle, namely phosphatidylcholine (PC) (18:0/22:6) and phosphatidylethanolamine (PE) (18:0/22:6). We also found that exercise training increased PC (18:0/22:6) and PE (18:0/22:6) in glycolytic muscle and that PGC-1α was required for these alterations. Because phospholipid fatty acid composition influences cell permeability and receptor stability at the cell membrane, these phospholipids may contribute to exercise training-mediated functional changes in the skeletal muscle. 相似文献
82.
Tanaka K Sato K Aoshiba K Azuma A Mizushima T 《American journal of physiology. Lung cellular and molecular physiology》2012,302(12):L1250-L1261
Bronchodilators (such as ipratropium bromide), steroids (such as fluticasone propionate), and newly developed anti-inflammatory drugs (such as roflumilast) are used for patients with chronic obstructive pulmonary disease (COPD). We recently reported that lecithinized superoxide dismutase (PC-SOD) confers a protective effect in mouse models of COPD. We here examined the therapeutic effect of the combined administration of PC-SOD with ipratropium bromide on pulmonary emphysema and compared the effect of PC-SOD to other types of drugs. The severity of emphysema in mice was assessed by various criteria. Lung mechanics (elastance) and respiratory function (ratio of forced expiratory volume in the first 0.05 s to forced vital capacity) were assessed. Administration of PC-SOD by inhalation suppressed elastase-induced pulmonary emphysema, alteration of lung mechanics, and respiratory dysfunction. The concomitant intratracheal administration of ipratropium bromide did not alter the ameliorating effects of PC-SOD. Administration of ipratropium bromide, fluticasone propionate, or roflumilast alone did not suppress the elastase-induced increase in the pulmonary level of superoxide anion, pulmonary inflammatory response, pulmonary emphysema, alteration of lung mechanics, or respiratory dysfunction as effectively as did PC-SOD. PC-SOD, but not the other drugs, showed a therapeutic effect even when the drug was administered after the development of emphysema. PC-SOD also suppressed the cigarette smoke-induced pulmonary inflammatory response and increase in airway resistance. Based on these results, we consider that the inhalation of PC-SOD would be therapeutically beneficial for COPD. 相似文献
83.
Velikkakath AK Nishimura T Oita E Ishihara N Mizushima N 《Molecular biology of the cell》2012,23(5):896-909
Macroautophagy is an intracellular degradation system by which cytoplasmic materials are enclosed by the autophagosome and delivered to the lysosome. Autophagosome formation is considered to take place on the endoplasmic reticulum and involves functions of autophagy-related (Atg) proteins. Here, we report the identification and characterization of mammalian Atg2 homologues Atg2A and Atg2B. Simultaneous silencing of Atg2A and Atg2B causes a block in autophagic flux and accumulation of unclosed autophagic structures containing most Atg proteins. Atg2A localizes on the autophagic membrane, as well as on the surface of lipid droplets. The Atg2A region containing amino acids 1723-1829, which shows relatively high conservation among species, is required for localization to both the autophagic membrane and lipid droplet and is also essential for autophagy. Depletion of both Atg2A and Atg2B causes clustering of enlarged lipid droplets in an autophagy-independent manner. These data suggest that mammalian Atg2 proteins function both in autophagosome formation and regulation of lipid droplet morphology and dispersion. 相似文献
84.
The activity patterns and substratum selection for foraging of checkered snapper Lutjanus decussatus were observed. The foraging rate of small‐sized individuals (<150 mm in total length, LT) was significantly greater than that of large‐sized individuals (≥150 mm LT). There was significant positive use of live branching corals, whereas negative use of coral rubble, rocks and sand for both small‐sized and large‐sized individuals. 相似文献
85.
Toshiki Uchihara Ayako Nakamura Hiroshi Nakayama Kunimasa Arima Norio Ishizuka Hiroshi Mori Setsuo Mizushima 《The journal of histochemistry and cytochemistry》2003,51(9):1201-1206
We established a triple-labeling method with two rabbit polyclonal antibodies and a mouse monoclonal antibody and examined autopsied brain tissue with cotton wool plaques (CWPs). One of the polyclonal antibodies was so diluted (anti-Abeta42 or anti-Abeta40/1:30,000 or anti-von Willebrand factor/1:1000) that its visualization was possible only after amplification with the catalyzed reporter deposition (CARD) method. The other polyclonal antibody (anti-Abeta40 or anti-Abeta42/1:1000) was visualized with a fluorochrome conjugated to an anti-rabbit antibody that specifically visualized the latter polyclonal antibody because of its lower sensitivity. A monoclonal antibody, AT8, was superimposed to yield triple immunofluorolabeling. Serial optical sections with an interval of 0.3 micro m were reconstructed to allow three-dimensional (3D) observation of these three epitopes. Abeta40 was localized to core-like structures, mainly in layers I-III, and was sometimes in contact with the vascular wall, both without neuritic reactions. CWPs, present in layers I-VI, were labeled with anti-Abeta42 and were accompanied by neuritic reactions. These differences suggest that mechanisms of Abeta deposition and its relation to neuritic reactions or to blood vessels differ according to the lesion, even in the same microscopic field. 相似文献
86.
Structure of the [2Fe-2S] ferredoxin I from the blue-green alga Aphanothece sacrum at 2.2 A resolution 总被引:4,自引:0,他引:4
T Tsukihara K Fukuyama M Mizushima T Harioka M Kusunoki Y Katsube T Hase H Matsubara 《Journal of molecular biology》1990,216(2):399-410
Crystals of a [2Fe-2S] ferredoxin (Fd) I with a relative molecular mass of 10,480 were obtained from the blue-green alga Aphanothece sacrum. Each asymmetric unit of the crystal contains four molecules. An electron density map calculated by the single isomorphous replacement method with the anomalous dispersion at 2.5 A resolution was refined by averaging the four molecules in the asymmetric unit. Positional and isotropic thermal parameters for the non-hydrogen atoms of the four molecules and 158 water molecules were refined to an R-factor (R = sigma[Fo-Fc[/sigma Fo) of 0.23 by the restrained least-squares method. The estimated root-mean-square (r.m.s.) error for the atomic positions is 0.3 A. The r.m.s. deviations of equivalent C alpha atoms of the asymmetric-unit molecules superposed by the least-squares method average 0.35 A. The Fd molecule has a structure like the beta-barrel in the molecule of the [2Fe-2S] Fd from Spirulina platensis. A [2Fe-2S] cluster is bonded covalently to the protein molecule by four Fe-S, in which three of the Fe-S bonds are in a loop segment from position 38 to 47. The hydrophobic core inside the beta-barrel is formed by seven conservative residues: Val15, Val18, Ile24, Leu51, Ile74, Ala79 and Ile87. The molecular surface around Tyr23, Tyr80 and the active center may interact with ferredoxin-NADP+ reductase. One of the two iron atoms of the [2Fe-2S] cluster should be more easily reduced than the other because of differences in the hydrogen-bonding scheme and the hydrophobicity around the atoms. 相似文献
87.
Tomohiro Ueda Tomohisa Takagi Kazuhiro Katada Takaya Iida Katsura Mizushima Osamu Dohi Tetsuya Okayama Naohisa Yoshida Kazuhiro Kamada Kazuhiko Uchiyama Osamu Handa Takeshi Ishikawa Hideyuki Konishi Yuji Naito Yukio Nagasaki Yoshito Itoh 《Biochemical and biophysical research communications》2018,495(2):2044-2049
Background
Intestinal ischemia-reperfusion (I-R) injury is a serious abdominal condition leading to multiple organ failure with high mortality. However, no reliable treatment is available. A redox nanoparticle (RNPO) was recently developed, and its efficacy for several intestinal inflammatory conditions has been reported. To this end, the aim of this study was to investigate the therapeutic effects of RNPO on intestinal I-R injury in mice.Methods
Ischemia was induced in the small intestine of C57BL/6 mice by occluding the superior mesenteric artery for 45 min under anesthesia followed by reperfusion for 4 h. Mice were orally administered the vehicle or RNPO 1 h before ischemia. Inflammatory markers such as histological findings, thiobarbituric acid (TBA)-reactive substances as an index of lipid peroxidation, myeloperoxidase (MPO) activity as an index of neutrophil infiltration, and expression of pro-inflammatory cytokine mRNA in the intestinal mucosa were assessed.Results
Induction of I-R caused a significant increase in inflammatory markers (histological scores, TBA-reactive substances, MPO activity, and expression of keratinocyte chemoattractant mRNA). These changes were significantly attenuated in RNPO-treated mice as compared to vehicle-treated mice.Conclusion
Orally administered RNPO attenuated intestinal I-R injury in mice in association with reductions in neutrophil infiltration and lipid peroxidation, suggesting the possibly potential of RNPO as a therapeutic agent for intestinal I-R injury. 相似文献88.
89.
Effects of prolonged delivery of brain-derived neurotrophic factor on the fate of neural stem cells transplanted into the developing rat retina 总被引:8,自引:0,他引:8
Suzuki T Ooto S Akagi T Amemiya K Igarashi R Mizushima Y Takahashi M 《Biochemical and biophysical research communications》2003,309(4):843-847
One of the major roles of brain-derived neurotrophic factor (BDNF) is to promote the differentiation and support the survival of neurons in the central nervous system. The objective of the present study was to evaluate the effect of BDNF on the fate of adult rat hippocampus-derived neural stem cells (AHPCs) transplanted into the developing rat retina. Immunohistochemical analysis showed a significant increase in the ratio of grafted AHPCs stained for MAP2ab (P<0.05) and a marked decrease in the ratio of nestin-positive grafted cells in the slow-releasing BDNF group compared with the control group. The respective changes in the ratios of MAP5 and GFAP-positive grafted cells were comparable for the two groups. The results reported here suggest a potentially beneficial role for extended delivery of BDNF in the differentiation of grafted neural stem cells, which may lead to a novel modification of stem cell transplantation. 相似文献
90.