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51.
Kumiko Kitamura Yusuke Takamura Taku Iwamoto Mitsuru Nomura Hideaki Iwasaki Motoyasu Ohdera 《Bioscience, biotechnology, and biochemistry》2017,81(2):335-342
Skeletal muscle is an important organ for controlling the development of type 2 diabetes. We discovered Panax notoginseng roots as a candidate to improve hyperglycemia through in vitro muscle cells screening test. Saponins are considered as the active ingredients of ginseng. However, in the body, saponins are converted to dammarane-type triterpenes, which may account for the anti-hyperglycemic activity. We developed a method for producing a dammarane-type triterpene extract (DTE) from Panax notoginseng roots and investigated the extract’s potential anti-hyperglycemic activity. We found that DTE had stronger suppressive activity on blood glucose levels than the saponin extract (SE) did in KK-Ay mice. Additionally, DTE improved oral glucose tolerance, insulin sensitivity, glucose uptake, and Akt phosphorylation in skeletal muscle. These results suggest that DTE is a promising agent for controlling hyperglycemia by enhancing glucose uptake in skeletal muscle. 相似文献
52.
Masanao Watanabe Keiji Itoh Kuniya Abe Toshifumi Akizawa Kohji Ikenishi Mitsuru Furusawa 《Development, growth & differentiation》1992,34(2):223-231
In order to investigate whether a vasa -like protein is present in germ line cells of Xenopus , antibodies were produced which react specifically with synthetic oligopeptides of sequences from near the N- or C-termini or with one including the DEAD box of the Drosophila vasa protein.
Only the antibody against the oligopeptide including the DEAD box reacted strongly with germ plasm (GP) or with cytoplasm of germ line cells of Xenopus embryos by immunofluorescence microscopy. By immunoelectron microscopy, the antibody was demonstrated to react with the GP-specific structure, germinal granules, in cleaving embryos, and with their derivatives in the germ line cells of embryos at stages extending from gastrula to feeding tadpole. It also reacted with mitochondria not only in the GP and the germ line cells but also in somatic cells, and with myofibrils in muscle cells. By Western blotting, the antibody was shown to react with several bands of Mr 42–69 ± 103 in protein samples from Xenopus embryos. In samples from Drosophila ovaries, it reacted with a Mr 71 ± 103 band which was probably the vasa protein. This indicates the possibility that Xenopus embryos contain several DEAD family proteins. One of these is present on germinal granules, resembling the vasa protein on polar granules of Drosophila . 相似文献
Only the antibody against the oligopeptide including the DEAD box reacted strongly with germ plasm (GP) or with cytoplasm of germ line cells of Xenopus embryos by immunofluorescence microscopy. By immunoelectron microscopy, the antibody was demonstrated to react with the GP-specific structure, germinal granules, in cleaving embryos, and with their derivatives in the germ line cells of embryos at stages extending from gastrula to feeding tadpole. It also reacted with mitochondria not only in the GP and the germ line cells but also in somatic cells, and with myofibrils in muscle cells. By Western blotting, the antibody was shown to react with several bands of Mr 42–69 ± 10
53.
Kumpei Tanisawa Tomoko Ito Xiaomin Sun Ryuken Ise Satomi Oshima Zhen-Bo Cao Shizuo Sakamoto Masashi Tanaka Mitsuru Higuchi 《Genes & nutrition》2014,9(5):1-9
Genome-wide association studies identified single nucleotide polymorphisms (SNPs) associated with body mass index (BMI) in middle-aged populations; however, it is unclear whether these SNPs are associated with body fatness in elderly people. We examined the association between genetic risk score (GRS) from BMI-associated SNPs and body fatness in elderly Japanese men. We also examined the contribution of GRS, dietary macronutrient intake, and physical activity to body fatness by different age groups. GRS was calculated from 10 BMI-associated SNPs in 84 middle-aged (30–64 years) and 97 elderly (65–79 years) Japanese men; subjects were divided into low, middle, and high GRS groups. Dietary macronutrient intake was assessed using a questionnaire, and physical activity was evaluated using both a questionnaire and an accelerometer. The middle-aged individuals with a high GRS had greater BMI; waist circumference; and total abdominal fat, visceral fat, and subcutaneous fat areas than the middle-aged individuals with low GRS, whereas the indicators were not different between the GRS groups in elderly individuals. Multiple linear regression analysis showed that GRS was the strongest predictor of BMI, total abdominal fat, and visceral fat in the middle-aged group, whereas fat, alcohol, and protein intakes or vigorous-intensity physical activity were more strongly associated with these indicators than was GRS in the elderly group. These results suggest that GRS from BMI-associated SNPs is not predictive of body fatness in elderly Japanese men. The stronger contribution of dietary macronutrient intake and physical activity to body fatness may attenuate the genetic predisposition in elderly men. 相似文献
54.
Makoto Kiso Mitsuru Maeda Norio Kurihara Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(2):459-461
Meso-(1245/36)-1,2,4,5,6-pentachloro-3-methylthiocyclohexane, and (124/356)-1,2,4,5,6-pentachloro-3-methylthio and ethylthiocyclohexanes were prepared from (1234/56)-1,4,5,6-tetrachloro-2,3-epoxycyclohexane (α-BTC cis-epoxide). 相似文献
55.
Zui Fujimoto Rintaro Suzuki Takahiro Shiotsuki Wataru Tsuchiya Akira Tase Mitsuru Momma Toshimasa Yamazaki 《PloS one》2013,8(2)
Juvenile hormones (JHs) control a diversity of crucial life events in insects. In Lepidoptera which major agricultural pests belong to, JH signaling is critically controlled by a species-specific high-affinity, low molecular weight JH-binding protein (JHBP) in hemolymph, which transports JH from the site of its synthesis to target tissues. Hence, JHBP is expected to be an excellent target for the development of novel specific insect growth regulators (IGRs) and insecticides. A better understanding of the structural biology of JHBP should pave the way for the structure-based drug design of such compounds. Here, we report the crystal structure of the silkworm Bombyx mori JHBP in complex with two molecules of 2-methyl-2,4-pentanediol (MPD), one molecule (MPD1) bound in the JH-binding pocket while the other (MPD2) in a second cavity. Detailed comparison with the apo-JHBP and JHBP-JH II complex structures previously reported by us led to a number of intriguing findings. First, the JH-binding pocket changes its size in a ligand-dependent manner due to flexibility of the gate α1 helix. Second, MPD1 mimics interactions of the epoxide moiety of JH previously observed in the JHBP-JH complex, and MPD can compete with JH in binding to the JH-binding pocket. We also confirmed that methoprene, which has an MPD-like structure, inhibits the complex formation between JHBP and JH while the unepoxydated JH III (methyl farnesoate) does not. These findings may open the door to the development of novel IGRs targeted against JHBP. Third, binding of MPD to the second cavity of JHBP induces significant conformational changes accompanied with a cavity expansion. This finding, together with MPD2-JHBP interaction mechanism identified in the JHBP-MPD complex, should provide important guidance in the search for the natural ligand of the second cavity. 相似文献
56.
Yuriko Osakabe Naoko Arinaga Taishi Umezawa Shogo Katsura Keita Nagamachi Hidenori Tanaka Haruka Ohiraki Kohji Yamada So-Uk Seo Mitsuru Abo Etsuro Yoshimura Kazuo Shinozaki Kazuko Yamaguchi-Shinozaki 《The Plant cell》2013,25(2):609-624
Osmotic adjustment plays a fundamental role in water stress responses and growth in plants; however, the molecular mechanisms governing this process are not fully understood. Here, we demonstrated that the KUP potassium transporter family plays important roles in this process, under the control of abscisic acid (ABA) and auxin. We generated Arabidopsis thaliana multiple mutants for K+ uptake transporter 6 (KUP6), KUP8, KUP2/SHORT HYPOCOTYL3, and an ABA-responsive potassium efflux channel, guard cell outward rectifying K+ channel (GORK). The triple mutants, kup268 and kup68 gork, exhibited enhanced cell expansion, suggesting that these KUPs negatively regulate turgor-dependent growth. Potassium uptake experiments using 86radioactive rubidium ion (86Rb+) in the mutants indicated that these KUPs might be involved in potassium efflux in Arabidopsis roots. The mutants showed increased auxin responses and decreased sensitivity to an auxin inhibitor (1-N-naphthylphthalamic acid) and ABA in lateral root growth. During water deficit stress, kup68 gork impaired ABA-mediated stomatal closing, and kup268 and kup68 gork decreased survival of drought stress. The protein kinase SNF1-related protein kinases 2E (SRK2E), a key component of ABA signaling, interacted with and phosphorylated KUP6, suggesting that KUP functions are regulated directly via an ABA signaling complex. We propose that the KUP6 subfamily transporters act as key factors in osmotic adjustment by balancing potassium homeostasis in cell growth and drought stress responses. 相似文献
57.
An inulin fructotransferase producing difructose dianhydride I (EC 2.4.1.200) was purified from Arthrobacter ureafaciens A51-1. It had maximum activity at pH 5.5 and 45 °C, and was stable up to 80 °C. This is the highest thermal stability for this enzyme reported to date. The molecular mass was estimated to be 38000 by SDS-PAGE, and 61000 by gel filtration. It was therefore estimated to be a dimer. 相似文献
58.
Iigo M Alexander DB Long N Xu J Fukamachi K Futakuchi M Takase M Tsuda H 《Biochimie》2009,91(1):86-101
Oral administration of bovine lactoferrin (bLF) inhibits carcinogenesis in the colon and other organs in rats, and lung metastasis in mice. A likely mechanism by which bLF mediates its anticarcinogenesis effects is by enhanced expression of cytokines and subsequent activation of immune cells. Oral administration of bLF enhances expression of interleukin-18 (IL-18) mRNA in the mucosa of the small intestine of mice. Importantly, the pepsin hydrolysate of bLF (bLFH) also induced expression of IL-18 mRNA in the mouse small intestine and a peptide produced by pepsin digestion of bLF, bovine lactoferricin (bLFcin), induced expression of mature IL-18 in organ culture. In addition to IL-18, bLF and bLFcin both induced significant increases in caspase-1 activity in peritoneal macrophages and in organ cultures. The increase of mature IL-18 by macrophages was inhibited by caspase-1 inhibitor: caspase-1 is known to cleave the proform of IL-18 to produce active mature IL-18. Finally, bLF also induced expression of IFNgamma by peritoneal macrophages. Importantly, in IFNgamma knockout (GKO) mice, bLF administration resulted in increased expression of caspase-1 protein, but induction of IL-18 mRNA, caspase-1 activity, and mature IL-18 was not observed. These results indicate that orally administered bLF can induce expression of IFNgamma and caspase-1 in the small intestine. IFNgamma in turn increases expression of target genes, including IL-18. Active caspase-1 then cleaves pro-IL-18 to generate mature IL-18. Thus, bLF activates an effector pathway mediated by IFNgamma, caspase-1, and IL-18. We also show that ingested bLF is able to activate more than a single effector pathway. For example, in GKO mice while bLF administration could not activate the IFNgamma/caspase-1/IL-18 effector pathway, it was able to inhibit tumor growth and metastasis by activation of an IFNalpha/IL-7 effector pathway. 相似文献
59.
Yuri Katayama Kengo Maeda Takahiro Iizuka Masaharu Hayashi Yoshio Hashizume Mitsuru Sanada Hiromichi Kawai Atsunori Kashiwagi 《Mitochondrion》2009,9(5):306-313
To investigate the relationship between oxidative stress and progressive spread of the stroke-like lesions in mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) with 3243A>G mutation, we retrospectively analyzed the spread frequency in patients with and without treatment with the radical scavenger edaravone. Oxidative damage and defensive enzymes were histologically evaluated. Spread was significantly less frequent in the patients treated with edaravone. Although 8-hydroxy-2′-deoxyguanosine, a marker for oxidative damage of DNA, was obviously accumulated in peri-lesional surviving neurons, manganese superoxide dismutase and 8-oxoguanine glycosylase 1 were not up-regulated in those neurons. Increased oxidative stress and insufficient defense could be involved in the pathogenesis of the spreading lesions in MELAS. 相似文献
60.
Haruo Hashimoto Tomoo Eto Tsutomu Kamisako Naoko Hoya Teruhiko Hatakeyama Toshiro Arai Makoto Yokosuka Yasuyuki Ohnishi Mamoru Ito Kyoji Hioki Ryo Suzuki Mitsuru Ohsugi Muneo Saito Yoshito Ueyama Toshimasa Yamauchi Naoto Kubota Kazuyuki Tobe Takashi Kadowaki Norikazu Tamaoki Tatsuji Nomura Kinori Kosaka 《Experimental Animals》2008,57(4):407-411
Efficient reproduction using natural mating and reproduction technology [in vitro fertilization (IVF) and embryo transfer (ET)] was investigated in IRS2 deficient mice with C57BL/6JJcl genetic background (Irs2(-/-) mice) as a typical type 2 diabetes model. From the results using various combinations of Irs2(-/-) and Irs2(-/+) mice, the combination of female Irs2(-/+) x male Irs2(-/-) was found to be more efficient than other combinations. In applications of reproduction technology using IVF and ET, the combination of female Irs2(-/+) x male Irs2(-/-) involves the possibility of Irs2(-/-) production by repeats using female Irs2(-/+) mice. However, reproductive continuity using this combination is difficult because of dependence on human technique and the cost of ET. Therefore, we concluded that Irs2(-/-) mice should be produced by embryo transfer using Irs2(-/-) mice from a colony consisting of female Irs2(-/+) x male Irs2(-/-). 相似文献