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1.
C-reactive protein-induced upregulation of extracellular matrix metalloproteinase inducer in macrophages: inhibitory effect of fluvastatin 总被引:10,自引:0,他引:10
OBJECTIVE: Extracellular matrix metalloproteinase inducer (EMMPRIN) and matrix metalloproteinase (MMP)-9 were reported to be expressed at the macrophage-rich area in human coronary atherosclerotic plaque. We examined whether C-reactive protein (CRP) activates macrophages to express EMMPRIN and MMP-9 in vitro and whether statins inhibit it. METHODS AND RESULTS: Rat peritoneal macrophages were collected by peritoneal lavage, and were incubated in the presence or absence of CRP. CRP at 5 microg/ml increased the gene expression of EMMPRIN relative to GAPDH, measured by RT-PCR, by 1.67+/-0.07 fold at 24 h and by 1.85+/-0.49 fold at 48 h (both p<0.05). The gene expression of MMP-9 in the presence of CRP at 5 microg/ml was followed by 1.36+/-0.11 fold increase at 24 h and by 3.95+/-0.81 fold at 48 h (both p<0.05). CRP at 5 microg/ml for 48 h increased by 6 fold MMP-9 activity, measured by zymography, without affecting tissue inhibitor of metalloproteinases-1. Boiled CRP at 5 mug/ml for 48 h unaffected MMP-9 activity. Fluvastatin blocked the CRP-induced increases in EMMPRIN and MMP-9 expression and activity. Diphenylene iodonium, an inhibitor of NADPH oxidase, had a similar effect on MMP-9 activity. Fluvastatin suppressed the CRP-induced increases in 8-epi-prostaglandin F(2alpha) levels in the condition media. CONCLUSIONS: CRP is an activator for macrophages to enhance EMMPRIN and MMP-9 expression. Fluvastatin inhibits them presumably through its antioxidant effect. 相似文献
2.
Ning Ma Toshiro Tagawa Yusuke Hiraku Mariko Murata Xiaohui Ding Shosuke Kawanishi 《Nitric oxide》2006,14(2):137-143
Oral leukoplakia is a premalignant lesion associated with development of oral cancer. To clarify the mechanism of development of oral carcinogenesis from leukoplakia, we examined DNA damage in oral epithelium of biopsy specimens of patients with leukoplakia by immunohistochemical methods. Histological changes, such as epithelial dysplasia and infiltration of inflammatory cells were observed in oral tissues of leukoplakia patients. A double immunofluorescence labeling study demonstrated that the accumulation of mutagenic 8-nitroguanine, an indicator of nitrative DNA damage, and 8-oxo-7,8-dihydro-2'-deoxyguanosine, an indicator of oxidative DNA damage, was apparently observed in the oral epithelium of patients with leukoplakia, whereas little or no immunoreactivity was observed in normal oral mucosa. Expression of inducible nitric oxide synthase (iNOS) was also observed in oral epithelium of leukoplakia patients. Immunoreactivity of 3-nitrotyrosine, an indicator of nitrative stress, was observed in oral epithelial cells and colocalized with 8-nitroguanine. Moreover, proliferating cell nuclear antigen and p53 were expressed in 8-nitroguanine-positive epithelial cells in the basal layer. These results suggest that iNOS-mediated nitrative stress contributes to development of oral carcinogenesis from leukoplakia through DNA damage as well as oxidative stress. 相似文献
3.
Masabumi Funakoshi Manabu Tsuda Keigo Muramatsu Hiroshi Hatsuda Shinichi Morishita Toshiro Aigaki 《Biochemical and biophysical research communications》2011,(4):214
The insulin/insulin-like growth factor (IGF) and the target of rapamycin (TOR) signaling pathways are known to regulate lifespan in diverse organisms. However, only a limited number of genes involved in these pathways have been examined regarding their effects on lifespan. Through a gain-of-function screen in Drosophila, we found that overexpression of the wdb gene encoding a regulatory subunit of PP2A, and overexpression of the lkb1 gene encoding a serine/threonine kinase, reduced organ size and extended lifespan. Overexpression of wdb also reduced the level of phosphorylated AKT, while overexpression of lkb1 increased the level of phosphorylated AMPK and decreased the level of phosphorylated S6K. Taken together, our results suggest that wdb- and lkb1-dependent lifespan extension is mediated by downregulation of S6K, a downstream component of the insulin/IGF and TOR signaling pathways. 相似文献
4.
Eisuke Kato Michitsugu Yama Ryo Nakagomi Toshiro Shibata Keizo Hosokawa Jun Kawabata 《Bioorganic & medicinal chemistry letters》2012,22(20):6410-6412
Filipendula kamtschatica is a plant utilized as a traditional medicine by Ainu people in Japan, but its chemical constituents are not much studied. Pancreatic lipase inhibitors are a promising tool for the treatment of obesity. We searched for natural lipase inhibitors from F. kamtschatica and two new compounds were isolated along with the known flavonoid glycoside. The structure elucidation of new compounds revealed these two to be 2-O-caffeoyl-4-O-galloyl-l-threonic acid and 3-O-caffeoyl-4-O-galloyl-l-threonic acid, which can be recognized as a pancreatic lipase’s substrate-like structure. The isolated compounds all showed an inhibitory activity against porcine pancreatic lipase and one of the isomer, 3-O-caffeoyl-4-O-galloyl-l-threonic acid, possessed the most potent activity with IC50 value showing an order lower value compared to others. The substrate-like structure of the new compounds seemed to be important for their activity. 相似文献
5.
Kiyoshi Yoshizawa Toshiro Furukawa Makoto Tadenuma Masakazu Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(4):326-332
We have found that some straight-chained α-amino acids are converted by yeast to the alcohols with correspondingly longer carbon chains in the alcoholic fermentation contrary to F. Ehrlich’s scheme, i.e., isobutyl alcohol from alanine and active amyl alcohol from α-amino-n-butyric acid or threonine.In this report, we confirmed this fact in the alcoholic fermentation of many aliphatic amino acids by 2 yeast strains using gas chromatography. Moreover, n-propyl alcohol was proved to come from α-amino-n-butyric acid or threonine. Small quantities of n-propyl, isobutyl, active amyl and isoamyl alcohols were found in all the fermented solutions. There was some difference in the composition of higher alcohols of the alcoholic solutions fermented by different yeasts. 相似文献
6.
Intestinal crypt homeostasis results from neutral competition between symmetrically dividing Lgr5 stem cells 总被引:1,自引:0,他引:1
Snippert HJ van der Flier LG Sato T van Es JH van den Born M Kroon-Veenboer C Barker N Klein AM van Rheenen J Simons BD Clevers H 《Cell》2010,143(1):134-144
Intestinal stem cells, characterized by high Lgr5 expression, reside between Paneth cells at the small intestinal crypt base and divide every day. We have carried out fate mapping of individual stem cells by generating a multicolor Cre-reporter. As a population, Lgr5(hi) stem cells persist life-long, yet crypts drift toward clonality within a period of 1-6 months. We have collected short- and long-term clonal tracing data of individual Lgr5(hi) cells. These reveal that most Lgr5(hi) cell divisions occur symmetrically and do not support a model in which two daughter cells resulting from an Lgr5(hi) cell division adopt divergent fates (i.e., one Lgr5(hi) cell and one transit-amplifying [TA] cell per division). The cellular dynamics are consistent with a model in which the resident stem cells double their numbers each day and stochastically adopt stem or TA fates. Quantitative analysis shows that stem cell turnover follows a pattern of neutral drift dynamics. 相似文献
7.
Yoshida-Takashima Y Nunoura T Kazama H Noguchi T Inoue K Akashi H Yamanaka T Toki T Yamamoto M Furushima Y Ueno Y Yamamoto H Takai K 《Applied and environmental microbiology》2012,78(5):1311-1320
Viruses play important roles in marine surface ecosystems, but little is known about viral ecology and virus-mediated processes in deep-sea hydrothermal microbial communities. In this study, we examined virus-like particle (VLP) abundances in planktonic and attached microbial communities, which occur in physical and chemical gradients in both deep and shallow submarine hydrothermal environments (mixing waters between hydrothermal fluids and ambient seawater and dense microbial communities attached to chimney surface areas or macrofaunal bodies and colonies). We found that viruses were widely distributed in a variety of hydrothermal microbial habitats, with the exception of the interior parts of hydrothermal chimney structures. The VLP abundance and VLP-to-prokaryote ratio (VPR) in the planktonic habitats increased as the ratio of hydrothermal fluid to mixing water increased. On the other hand, the VLP abundance in attached microbial communities was significantly and positively correlated with the whole prokaryotic abundance; however, the VPRs were always much lower than those for the surrounding hydrothermal waters. This is the first report to show VLP abundance in the attached microbial communities of submarine hydrothermal environments, which presented VPR values significantly lower than those in planktonic microbial communities reported before. These results suggested that viral lifestyles (e.g., lysogenic prevalence) and virus interactions with prokaryotes are significantly different among the planktonic and attached microbial communities that are developing in the submarine hydrothermal environments. 相似文献
8.
This study determined the physical fitness component that contributes to improving and maintaining health status for each age group as well as quantifying the degree of the relationship between health status and physical fitness in middle-aged and elderly females. The participants were 2,371 females aged 30 to 69 years. Ten physical fitness tests and medical checkups were performed. The participants were divided into a healthy group and an unhealthy group according to health status. Multiple discriminant analysis was applied to the multivariate data. Correct discriminant probabilities of the multiple discriminant function to discriminate the healthy and unhealthy groups for females ranged from 63.0% to 77.5%. These results suggest that there is a relatively high relationship between health status and physical fitness level for middle-aged and elderly females. With each individual's discriminant score calculated by the obtained multiple discriminant function as the index of the degree of health, the Pearson's correlation coefficient of the discriminant score and the performance in each physical fitness test were calculated. The aging change from 30 to 69 years old was classified into four patterns according to the contribution. The result of this study is considered to be useful as objective data to prepare an exercise program considering the contribution of the physical fitness component of health status. 相似文献
9.
Sakazume S Ohashi H Sasaki Y Harada N Nakanishi K Sato H Emi M Endoh K Sohma R Kido Y Nagai T Kubota T 《Human genetics》2012,131(1):121-130
X-chromosome inactivation (XCI) is an essential mechanism in females that compensates for the genome imbalance between females and males. It is known that XCI can spread into an autosome of patients with X;autosome translocations. The subject was a 5-year-old boy with Prader?CWilli syndrome (PWS)-like features including hypotonia, hypo-genitalism, hypo-pigmentation, and developmental delay. G-banding, fluorescent in situ hybridization, BrdU-incorporated replication, human androgen receptor gene locus assay, SNP microarrays, ChIP-on-chip assay, bisulfite sequencing, and real-time RT-PCR were performed. Cytogenetic analyses revealed that the karyotype was 46,XY,der(X)t(X;15)(p21.1;q11.2),?15. In the derivative chromosome, the X and half of the chromosome 15 segments showed late replication. The X segment was maternal, and the chromosome 15 region was paternal, indicating its post-zygotic origin. The two chromosome 15s had a biparental origin. The DNA methylation level was relatively high in the region proximal from the breakpoint, and the level decreased toward the middle of the chromosome 15 region; however, scattered areas of hypermethylation were found in the distal region. The promoter regions of the imprinted SNRPN and the non-imprinted OCA2 genes were completely and half methylated, respectively. However, no methylation was found in the adjacent imprinted gene UBE3A, which contained a lower density of LINE1 repeats. Our findings suggest that XCI spread into the paternal chromosome 15 led to the aberrant hypermethylation of SNRPN and OCA2 and their decreased expression, which contributes to the PWS-like features and hypo-pigmentation of the patient. To our knowledge, this is the first chromosome-wide methylation study in which the DNA methylation level is demonstrated in an autosome subject to XCI. 相似文献
10.
Etsuro Yamaha Toshiro Mizuno Yutaka Hasebe Hiroyuki Takeda Fumio Yamazaki 《Development, growth & differentiation》1998,40(3):267-275
The teleost dorsoventral axis cannot be morphologically distinguished before gastrulation. Previous studies by the current authors have shown that localized dorsalizing activity in the yolk cell (YC) induces the dorsal tissues in the overlying blastoderm. In order to examine whether or not dorsal blastomeres are committed to their dorsal fate before the gastrula stage, a variety of transplant operations were performed in goldfish blastoderms at the mid- to late-blastula stages. When the blastoderm was cut from the YC, rotated horizontally at 180°, and recombined with the YC, the blastoderm frequently developed two axes, indicating that dorsal blastomeres of the blastula had already acquired the ability to differentiate into the organizer in the absence of dorsalizing signals from the YC. This result was further confirmed by experiments using ventralized embryos in which no dorsal structures formed: the axis formation was frequently observed in the normal blastoderm combined with the ventralized YC at the blastula stage. However, the axes formed in the absence of dorsal information from the YC exhibited a lower dorso-anterior index. Furthermore, the dorsal specification was not stably maintained when the dorsal cells were located far from the YC. These results suggest that the inductive and permissive influence of the YC may be required for the blastoderm to undergo full dorsal differentiation. 相似文献