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Shogo Tamura Masato Mukaide Yumi Katsuragi Wataru Fujii Koya Odaira Nobuaki Suzuki Nagaharu Tsukiji Shuichi Okamoto Atsuo Suzuki Takeshi Kanematsu Akira Katsumi Akira Takagi Katsuhide Ikeda Jun Ueyama Masaaki Hirayama Katsue Suzuki-Inoue Tadashi Matsushita Tetsuhito Kojima Fumihiko Hayakawa 《The Journal of biological chemistry》2022,298(5)
Bone marrow development and endochondral bone formation occur simultaneously. During endochondral ossification, periosteal vasculatures and stromal progenitors invade the primary avascular cartilaginous anlage, which induces primitive marrow development. We previously determined that bone marrow podoplanin (PDPN)-expressing stromal cells exist in the perivascular microenvironment and promote megakaryopoiesis and erythropoiesis. In this study, we aimed to examine the involvement of PDPN-expressing stromal cells in postnatal bone marrow generation. Using histological analysis, we observed that periosteum-derived PDPN-expressing stromal cells infiltrated the cartilaginous anlage of the postnatal epiphysis and populated on the primitive vasculature of secondary ossification center. Furthermore, immunophenotyping and cellular characteristic analyses indicated that the PDPN-expressing stromal cells constituted a subpopulation of the skeletal stem cell lineage. In vitro xenovascular model cocultured with human umbilical vein endothelial cells and PDPN-expressing skeletal stem cell progenies showed that PDPN-expressing stromal cells maintained vascular integrity via the release of angiogenic factors and vascular basement membrane-related extracellular matrices. We show that in this process, Notch signal activation committed the PDPN-expressing stromal cells into a dominant state with basement membrane-related extracellular matrices, especially type IV collagens. Our findings suggest that the PDPN-expressing stromal cells regulate the integrity of the primitive vasculatures in the epiphyseal nascent marrow. To the best of our knowledge, this is the first study to comprehensively examine how PDPN-expressing stromal cells contribute to marrow development and homeostasis. 相似文献
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Coclaurine N-methyltransferase from Coptis japonica catalyzes the N-methylation of coclaurine as well as simple tetrahydroisoquinoline. We examined the possibility of converting 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline into its N-methylated product using transgenic Escherichia coli, which expressed recombinant coclaurine N-methyltransferase, without the addition of a methyl-group donor. Transgenic E. coli successfully N-methylated the substrate added to the medium and excreted the product. Limitation of bioconversion by the supply of methyl-group donor is discussed. 相似文献
36.
Kohno K Okamoto I Sano O Arai N Iwaki K Ikeda M Kurimoto M 《Bioscience, biotechnology, and biochemistry》2004,68(1):138-145
In this study, we have examined the anti-inflammatory actions of royal jelly (RJ) at a cytokine level. When supernatants of RJ suspensions were added to a culture of mouse peritoneal macrophages stimulated with lipopolysaccharide and IFN-gamma, the production of proinflammatory cytokines, such as TNF-alpha, IL-6, and IL-1, was efficiently inhibited in a dose-dependent manner without having cytotoxic effects on macrophages. This suggests that RJ contains factor(s) responsible for the suppression of proinflammatory cytokine secretion. We named the factor for honeybees RJ-derived anti-inflammatory factor (HBRJ-AIF), and further investigated the molecular aspects of it. Size fractionation study showed that HBRJ-AIF is composed of substances of low (< 5 kDa) and high (> 30 kDa) molecular weights, with the former being a major component. Chromatographic analysis showed that MRJP3 is one candidate for the HBRJ-AIF with high molecular weights. Thus, our results suggest that RJ has anti-inflammatory actions through inhibiting proinflammatory cytokine production by activated macrophages. 相似文献
37.
Suppressive effect of a hot water extract of adzuki beans (Vigna angularis) on hyperglycemia after sucrose loading in mice and diabetic rats 总被引:3,自引:0,他引:3
Itoh T Kita N Kurokawa Y Kobayashi M Horio F Furuichi Y 《Bioscience, biotechnology, and biochemistry》2004,68(12):2421-2426
A hot water extract obtained by boiling adzuki beans (Vigna angularis) to produce bean paste for Japanese cake showed inhibitory activity against alpha-glucosidase, alpha-amylase, maltase, sucrase, and isomaltase after HP-20 column chromatography. The IC(50) values for each hydrolylase were 0.78 mg/ml (alpha-amylase), 2.45 mg/ml (maltase), 5.37 mg/ml (sucrase), and 1.75 mg/ml (isomaltase). The active fraction showed potential hypoglycemic activity in both normal mice and streptozotocin (STZ)-induced diabetic rats after an oral administration of sucrose, but did not show any effect on the blood glucose concentration after glucose administration, suggesting that the active fraction suppressed the postprandial blood glucose level by inhibiting alpha-glucosidase and alpha-amylase, irrespective of the endogenous blood insulin level. 相似文献
38.
Koya-Miyata S Okamoto I Ushio S Iwaki K Ikeda M Kurimoto M 《Bioscience, biotechnology, and biochemistry》2004,68(4):767-773
We have previously shown that royal jelly (RJ) promoted collagen production by skin fibroblasts in the presence of ascorbic acid-2-O-alpha-glucoside (AA-2G). In this study, we purified the honeybee RJ-derived collagen production-promoting factor (HBRJ-CPF) from an alkali-solubilized fraction of RJ by C18 reverse-phase column chromatography. The elution profile by the C18 column chromatography and the molecular mass of the purified HBRJ-CPF material coincided with those of 10-hydroxy-2-decenoic acid (10H2DA). We then examined the collagen production-promoting activities of several commercially available fatty acids contained in RJ. We found that 10H2DA and 10-hydroxydecanoic acid increased the collagen production in a dose-dependent manner. Furthermore, 10H2DA induced the fibroblast cell line, NHDF, to produce transforming growth factor-beta 1 (TGF-beta 1) which is an important factor for collagen production. As expected, the collagen production-promoting activity of 10H2DA was neutralized by the anti-TGF-beta 1 antibody. These result suggest that HBRJ-CPF identified as 10H2DA promoted the collagen production of AA-2G-treated fibroblasts by inducing TGF-beta 1 production. 相似文献
39.
Karl?G.?MuellerEmail author Michael?U.?Lampérth Fumihiko?Kimura 《The International Journal of Life Cycle Assessment》2004,9(4):227-235
Background and Objective
Life cycle assessment (LCA) is a highly data intensive undertaking, where collecting the life cycle inventory (LCI) data is the most labour intensive part. The aim of this paper is to show a method for representing the LCI in a simplified manner which not only allows an estimative, quantitative LCA, but also the application of advanced analysis methods to LCA. 相似文献40.
We examined the effect of a high-fat diet on the diabetes-related traits of the Japanese Fancy mouse 1 (JF1), MSM, and C57BL/6J (B6J) mice. MSM and JF1 mice were derived from Mus musculus molossinus. B6J is a commonly used laboratory strain, with the vast majority of genome segments derived from Mus musculus domesticus and Mus musculus musculus, and is susceptible to high-fat diet-induced type 2 diabetes. None of the strains showed symptoms of diabetes or obesity when fed a laboratory chow diet. Under a high-fat diet, JF1 mice developed impaired glucose tolerance, hyperglycemia, hyperinsulinemia, and obesity. B6J mice fed a high-fat diet mildly developed these diabetes-related traits compared to JF1 mice fed a high-fat diet. JF1 mice fed a high-fat diet were classified as having type 2 diabetes and were susceptible to high-fat diet-induced diabetes and obesity. On the other hand, MSM mice were resistant to high-fat diet-induced diabetes. These results indicate that the JF1 strain, with its unique genetic origin, is a useful new animal model of high-fat diet-induced diabetes and obesity. Further investigations using JF1 mice will help to clarify the role of the high-fat diet on human diabetes and obesity. 相似文献