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到目前为止,已从掘海绵属中分离得到200多种化合物,主要特征化学成分为萜类,多卤代化合物,甾醇等物质;本文按照化合物结构类型进行了归纳,综述了该类海绵中化学成分并简述了它们的药理作用. 相似文献
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Huajun Zheng Hong Liang Yuezhu Wang Maohua Miao Tao Shi Fen Yang Enuo Liu Wei Yuan Zai-Si Ji De-Kun Li 《PloS one》2016,11(11)
Eczema is frequently the first manifestation of an atopic diathesis and alteration in the diversity of gut microbiota has been reported in infants with eczema. To identify specific bacterial communities associated with eczema, we conducted a case-control study of 50 infants with eczema (cases) and 51 healthy infants (controls). We performed high-throughput sequencing for V3–V4 hypervariable regions of the 16S rRNA genes from the gut fecal material. A total of 12,386 OTUs (operational taxonomic units) at a 97% similarity level were obtained from the two groups, and we observed a difference in taxa abundance, but not the taxonomic composition, of gut microbiota between the two groups. We identified four genera enriched in healthy infants: Bifidobacterium, Megasphaera, Haemophilus and Streptococcus; and five genera enriched in infants with eczema: Escherichia/Shigella, Veillonella, Faecalibacterium, Lachnospiraceae incertae sedis and Clostridium XlVa. Several species, such as Faecalibacterium prausnitzii and Ruminococcus gnavus, that are known to be associated with atopy or inflammation, were found to be significantly enriched in infants with eczema. Higher abundance of Akkermansia muciniphila in eczematous infants might reduce the integrity of intestinal barrier function and therefore increase the risk of developing eczema. On the other hand, Bacteroides fragilis and Streptococcus salivarius, which are known for their anti-inflammatory properties, were less abundant in infants with eczema. The observed differences in genera and species between cases and controls in this study may provide insight into the link between the microbiome and eczema risk. 相似文献
996.
Zhu J Li Z Zhang G Meng K Kuang W Li J Zhou X Li R Peng H Dai C Shen JK Gong F Xu Y Liu S 《PloS one》2011,6(8):e23720
Purpose
To explore the effects of Icaritin on chronic myeloid leukemia (CML) cells and underlying mechanisms.Method
CML cells were incubated with various concentration of Icaritin for 48 hours, the cell proliferation was analyzed by MTT and the apoptosis was assessed with Annexin V and Hoechst 33258 staining. Cell hemoglobinization was determined. Western blotting was used to evaluate the expressions of MAPK/ERK/JNK signal pathway and Jak-2/Phorpho-Stat3/Phorsph-Akt network-related protein. NOD-SCID nude mice were applied to demonstrate the anti-leukemia effect of Icaritin in vivo.Results
Icaritin potently inhibited proliferation of K562 cells (IC50 was 8 µM) and primary CML cells (IC50 was 13.4 µM for CML-CP and 18 µM for CML-BC), induced CML cells apoptosis and promoted the erythroid differentiation of K562 cells with time-dependent manner. Furthermore, Icaritin was able to suppress the growth of primary CD34+ leukemia cells (CML) and Imatinib-resistant cells, and to induce apoptosis. In mouse leukemia model, Icaritin could prolong lifespan of NOD-SCID nude mice inoculated with K562 cells as effective as Imatinib without suppression of bone marrow. Icaritin could up-regulate phospho-JNK or phospho-C-Jun and down-regulate phospho-ERK, phospho-P-38, Jak-2, phospho-Stat3 and phospho-Akt expression with dose- or time-dependent manner. Icaritin had no influence both on c-Abl and phospho-c-Abl protein expression and mRNA levels of Bcr/Abl.Conclusion
Icaritin from Chinese herb medicine may be a potential anti-CML agent with low adverse effect. The mechanism of anti-leukemia for Icaritin is involved in the regulation of Bcr/Abl downstream signaling. Icaritin may be useful for an alternative therapeutic choice of Imatinib-resistant forms of CML. 相似文献997.
998.
McCormick MM Rahimi F Bobryshev YV Gaus K Zreiqat H Cai H Lord RS Geczy CL 《The Journal of biological chemistry》2005,280(50):41521-41529
Atherogenesis is a complex process involving inflammation. S100A8 and S100A9, the Ca2+-binding neutrophil cytosolic proteins, are associated with innate immunity and regulate processes leading to leukocyte adhesion and transmigration. In neutrophils and monocytes the S100A8-S100A9 complex regulates phosphorylation, NADPH-oxidase activity, and fatty acid transport. The proteins have anti-microbial properties, and S100A8 may play a role in oxidant defense in inflammation. Murine S100A8 is regulated by inflammatory mediators and recruits macrophages with a proatherogenic phenotype. S100A9 but not S100A8 was found in macrophages in ApoE-/- murine atherosclerotic lesions, whereas both proteins are expressed in human giant cell arteritis. Here we demonstrate S100A8 and S100A9 protein and mRNA in macrophages, foam cells, and neovessels in human atheroma. Monomeric and complexed forms were detected in plaque extracts. S100A9 was strongly expressed in calcifying areas and the surrounding extracellular matrix. Vascular matrix vesicles contain high levels of Ca2+-binding proteins and phospholipids that regulate calcification. Matrix vesicles characterized by electron microscopy, x-ray microanalysis, nucleoside triphosphate pyrophosphohydrolase assay and cholesterol/phospholipid analysis contained predominantly S100A9. We propose that S100A9 associated with lipid structures in matrix vesicles may influence phospholipid-Ca2+ binding properties to promote dystrophic calcification. S100A8 and S100A9 were more sensitive to hypochlorite oxidation than albumin or low density lipoprotein and immunoaffinity confirmed S100A8-S100A9 complexes; some were resistant to reduction, suggesting that hypochlorite may contribute to protein cross-linking. S100A8 and S100A9 in atherosclerotic plaque and calcifying matrix vesicles may significantly influence redox- and Ca2+-dependent processes during atherogenesis and its chronic complications, particularly dystrophic calcification. 相似文献
999.
Up-regulation of adipogenin, an adipocyte plasma transmembrane protein, during adipogenesis 总被引:1,自引:0,他引:1
Hong YH Hishikawa D Miyahara H Tsuzuki H Nishimura Y Gotoh C Choi KC Hokari Y Takagi Y Lee HG Cho KK Roh SG Sasaki S 《Molecular and cellular biochemistry》2005,276(1-2):133-141
Until now, the various proteins highly expressed in adipose tissues have been identified and characterized by traditional gene cloning techniques. However, methods of computer analysis have been developed to compare the levels of expression among various tissues, and genes whose expression levels differ significantly between tissues have been found. Among these genes, we report on the possible function of a new adipose-specific gene, showed higher expression in adipose tissue through ‘Search Expression’ on Genome Institute of Norvartis Research Foundation (GNF) SymAtlas v0.8.0. This database has generated and analyzed gene expression of each gene in diverse samples of normal tissues, organs, and cell lines. This newly discovered gene product was named adipogenin because of its role in stimulating adipocyte differentiation and development. Adipogenin mRNA was highly expressed in four different fat depots, and exclusively expressed in adipocytes isolated from adipose tissues. The level of adipogenin mRNA was up-regulated in the subcutaneous and visceral adipose tissues of mice fed a high-fat diet compared to those on the control diet. The expression of adipogenin mRNA is dramatically elevated during adipocyte differentiation of 3T3-L1 cells. Troglitazone, which up-regulated peroxisome proliferators-activated receptor γ2 (PPAR-γ2) expression, increased adipogenin mRNA expression, although this gene was down-regulated by retinoic acid. Confocal image analyses of green-fluorescent protein-adipogenin (pEGFP-adipogenin) transiently expressed in 3T3-L1 adipocytes showed that adipogenin was strictly localized to membranes and was absent from the cytosol. Moreover, small interfering RNA (siRNA) mediated a reduction of adipogenin mRNA in 3T3-L1 cells and blocked the process of adipocyte differentiation. These results indicate that adipogenin, an adipocyte-specific membrane protein, may be involved with adipogenesis, as one of the regulators of adipose tissue development.Yeon-Hee Hong and Daisuke Hishikawa contributed equally to this work 相似文献
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