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141.
Jung Tak Park Mitsuo Kato Hang Yuan Nancy Castro Linda Lanting Mei Wang Rama Natarajan 《The Journal of biological chemistry》2013,288(31):22469-22480
Glomerular hypertrophy is a hallmark of diabetic nephropathy. Akt kinase activated by transforming growth factor-β1 (TGF-β) plays an important role in glomerular mesangial hypertrophy. However, the mechanisms of Akt activation by TGF-β are not fully understood. Recently, miR-200 and its target FOG2 were reported to regulate the activity of phosphatidylinositol 3-kinase (the upstream activator of Akt) in insulin signaling. Here, we show that TGF-β activates Akt in glomerular mesangial cells by inducing miR-200b and miR-200c, both of which target FOG2, an inhibitor of phosphatidylinositol 3-kinase activation. FOG2 expression was reduced in the glomeruli of diabetic mice as well as TGF-β-treated mouse mesangial cells (MMC). FOG2 knockdown by siRNAs in MMC activated Akt and increased the protein content/cell ratio suggesting hypertrophy. A significant increase of miR-200b/c levels was detected in diabetic mouse glomeruli and TGF-β-treated MMC. Transfection of MMC with miR-200b/c mimics significantly decreased the expression of FOG2. Conversely, miR-200b/c inhibitors attenuated TGF-β-induced decrease in FOG2 expression. Furthermore, miR-200b/c mimics increased the protein content/cell ratio, whereas miR-200b/c inhibitors abrogated the TGF-β-induced increase in protein content/cell. In addition, down-regulation of FOG2 by miR-200b/c could activate not only Akt but also ERK, which was also through PI3K activation. These data suggest a new mechanism for TGF-β-induced Akt activation through FOG2 down-regulation by miR-200b/c, which can lead to glomerular mesangial hypertrophy in the progression of diabetic nephropathy. 相似文献
142.
143.
Kazuyoshi Kitaoka Mitsuo Kitamura Shun Aoi Noriyuki Shimizu Kazuo Yoshizaki 《Bioelectromagnetics》2013,34(1):43-51
An extremely low‐frequency magnetic field (ELF‐MF) is generated by power lines and household electrical devices. Many studies have suggested an association between chronic ELF‐MF exposure and anxiety and/or depression. The mechanism of these effects is assumed to be a stress response induced by ELF‐MF exposure. However, this mechanism remains controversial. In the present study, we investigated whether chronic ELF‐MF exposure (intensity, 3 mT; total exposure, 200 h) affected emotional behavior and corticosterone synthesis in mice. ELF‐MF‐treated mice showed a significant increase in total immobility time in a forced swim test and showed latency to enter the light box in a light–dark transition test, compared with sham‐treated (control) mice. Corticosterone secretion was significantly high in the ELF‐MF‐exposed mice; however, no changes were observed in the amount of the adrenocorticotropic hormone and the expression of genes related to stress response. Quantification of the mRNA levels of adrenal corticosteroid synthesis enzymes revealed a significant reduction in Cyp17a1 mRNA in the ELF‐MF‐exposed mice. Our findings suggest the possibility that high intensity and chronic exposure to ELF‐MF induces an increase in corticosterone secretion, along with depression‐ and/or anxiety‐like behavior, without enhancement of the hypothalamic–pituitary–adrenal axis. Bioelectromagnetics 34:43–51, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
144.
Masamitsu Konno Atsushi Hamabe Shinichiro Hasegawa Hisataka Ogawa Takahito Fukusumi Shimpei Nishikawa Katsuya Ohta Yoshihiro Kano Miyuki Ozaki Yuko Noguchi Daisuke Sakai Toshihiro Kudoh Koichi Kawamoto Hidetoshi Eguchi Taroh Satoh Masahiro Tanemura Hiroaki Nagano Yuichiro Doki Masaki Mori Hideshi Ishii 《Development, growth & differentiation》2013,55(3):309-318
Adipose tissue‐derived mesenchymal stem cells (ADSCs) are multipotent and can differentiate into various cell types, including osteocytes, adipocytes, neural cells, vascular endothelial cells, cardiomyocytes, pancreatic β‐cells, and hepatocytes. Compared with the extraction of other stem cells such as bone marrow‐derived mesenchymal stem cells (BMSCs), that of ADSCs requires minimally invasive techniques. In the field of regenerative medicine, the use of autologous cells is preferable to embryonic stem cells or induced pluripotent stem cells. Therefore, ADSCs are a useful resource for drug screening and regenerative medicine. Here we present the methods and mechanisms underlying the induction of multilineage cells from ADSCs. 相似文献
145.
Ahmed Abdelmoniem Mousa Shinuo Cao Gabriel Oluga Aboge Mohamad Alaa Terkawi Ahmed El Kirdasy Akram Salama Mabrouk Attia Mahmoud Aboulaila Mo Zhou Ketsarin Kamyingkird Paul Franck Adjou Moumouni Tatsunori Masatani Sami Ahmed Abd El Aziz Waheed Mohammed Moussa Bayin Chahan Shinya Fukumoto Yoshifumi Nishikawa Salah Sayed El Ballal Xuenan Xuan 《Experimental parasitology》2013
Identification and molecular characterization of Babesia gibsoni proteins with potential antigenic properties are crucial for the development and validation of the serodiagnostic method. In this study, we isolated a cDNA clone encoding a novel B. gibsoni 76-kDa protein by immunoscreening of the parasite cDNA library. Computer analysis revealed that the protein presents a glutamic acid-rich region in the C-terminal. Therefore, the protein was designated as B. gibsoni glutamic acid-rich protein (BgGARP). A BLASTp analysis of a translated BgGARP polypeptide demonstrated that the peptide shared a significant homology with a 200-kDa protein of Babesia bigemina and Babesia bovis. A truncated BgGARP cDNA (BgGARPt) encoding a predicted 13-kDa peptide was expressed in Escherichia coli (E. coli), and mouse antisera against the recombinant protein were used to characterize a corresponding native protein. The antiserum against recombinant BgGARPt (rBgGARPt) recognized a 140-kDa protein in the lysate of infected erythrocytes, which was detectable in the cytoplasm of the parasites by confocal microscopic observation. In addition, the specificity and sensitivity of enzyme-linked immunosorbent assay (ELISA) with rBgGARPt were evaluated using B. gibsoni-infected dog sera and specific pathogen-free (SPF) dog sera. Moreover, 107 serum samples from dogs clinically diagnosed with babesiosis were examined using ELISA with rBgGARPt. The results showed that 86 (80.4%) samples were positive by rBgGARPt-ELISA, which was comparable to IFAT and PCR as reference test. Taken together, these results demonstrate that BgGARP is a suitable serodiagnostic antigen for detecting antibodies against B. gibsoni in dogs. 相似文献
146.
Kentaro Takai Yasunao Inoue Yasuko Konishi Atsushi Suwa Yoshiharu Uruno Harumi Matsuda Tomokazu Nakako Mutsuko Sakai Hiroyuki Nishikawa Gakuji Hashimoto Takeshi Enomoto Atsushi Kitamura Yasuaki Uematsu Akihiko Kiyoshi Takaaki Sumiyoshi 《Bioorganic & medicinal chemistry letters》2013,23(16):4644-4647
We designed and synthesized N-substituted 8-azatetrahydroquinolone derivatives as selective M1 and M4 muscarinic acetylcholine receptors agonists. Optimization of selected derivatives led to the discovery of compound 7 as a highly potent M1 and M4 agonist with weak hERG inhibition. Oral administration of compound 7 improved psychosis-like behavior in rats. 相似文献
147.
Mitsuo Namiki Yoshishige Okazawa Akira Matsuyama 《Bioscience, biotechnology, and biochemistry》2013,77(6):509-514
Inactivation of crystalline enzyme, Streptomyces protease G, by γ-ray irradiation in an aqueous system has been investigated. It is indicated that inactivation of the enzyme is attributable mainly to the indirect action of radiation. The inactivation curve is exponential and the G-value for enzyme inactivation is calculated as 0.1 at an enzyme concentration of 1×10?5m, which is not influenced by varying pH. Effects of various other solutes on radiation inactivation have been also studied. Halogen ions, especially iodine ion, and nitrite ion are most protective among various inorganic anions examined, and alkali metal and alkali earth metal cations are ineffective. Among various organic compounds examined, sulfur-containg compounds and unsaturated compounds are generally effective for protection of enzyme activity against radiation damages. The protective effect of benzene is enhanced by the substitution of electron donating groups. Chloroform and chloral are found to act as a synergist for irradiation inactivation. 相似文献
148.
Sretsei Saittagaroon Shunro Kawakishi Mitsuo Namiki 《Bioscience, biotechnology, and biochemistry》2013,77(9):2301-2307
The volatile components of roasted and unroasted dried coconut shreds, isolated by steam distillation, were analyzed by GC and GC-MS. Seventeen compounds were identified from the unroasted coconut, and nine of them were newly identified in coconut meat aroma. Saturated delta-C8, C10, and C12 lactones were determined as the main components giving the characteristic mild, sweet, and pleasant coconut flavor. The roasted coconut gave the strong characteristic sweet and nutty aroma, and the GC-MS indicated the saturated delta-lactones as main components, and six pyrazines, two furans, and two pyrroles also found seemed to contribute greatly to the nut-like aroma of roasted coconut. The defatted and roasted meal gave a strong nut-like and burnt odor, but not the characteristic sweet aroma. A large increase in pyrazines and other Maillard reaction products and an absence of lactones and fatty acid esters were observed in the volatiles of the roasted-defatted coconut meal. 相似文献
149.
Mitsuo Namiki Yoshishige Okazawa Akira Matsuyama 《Bioscience, biotechnology, and biochemistry》2013,77(2):115-123
Effects of various chemical agents on the synergistic action of NaCl to the radiation inactivation of bacteria and yeast were studied. The remarkable modification of the radiation lethal effect by some reagents is considered to be a strong evidence for an indirect nature of NaCl synergistic action during irradiation. Most of these modification effects were restricted to the actions during irradiation, supporting the free radical hypothesis in which the short-life active species formed by radiation were considered to attack bacterial cells. Furthermore, pre-irradiation effects under various conditions suggest that the enhancement of radiation lethal effect by NaCl may involve the intracellular events. 相似文献
150.
The toxicity of dimethyl sulfoxide (Me2SO) was examined in HeLa cells cultured at 37°C for up to 72 hr. The growth of the cells was measured by a colorimetric method with the use of 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), which gave good correlation between the cell number and the color development from the reduction of MTT under suitable conditions. When the initial number of cells was 3 × 104/ml, Me2SO at 1% or less had no apparent effect on prolifiration for up to 48 hr of incubation, but in longer incubations, cell growth was repressed. When the initial number of cells was 3 × 105/ml, the effect of Me2SO was similar. 相似文献