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41.
Hong Ki Min Sung-Min Kim Seung-Ye Baek Jung-Won Woo Jin-Sil Park Mi-La Cho Jennifer Lee Seung-Ki Kwok Sae Woong Kim Sung-Hwan Park 《PloS one》2015,10(11)
Introduction
Oxidative stress plays a role in the pathogenesis of rheumatoid arthritis (RA). Anthocyanin is a plant antioxidant. We investigated the therapeutic effects of anthocyanin extracted from black soybean seed coats (AEBS) in a murine model of collagen-induced arthritis (CIA) and human peripheral blood mononuclear cells (PBMCs) and explored possible mechanisms by which AEBS might exert anti-arthritic effects.Material and Methods
CIA was induced in DBA/1J mice. Cytokine levels were measured via enzyme-linked immunosorbent assays. Joints were assessed in terms of arthritis incidence, clinical arthritis scores, and histological features. The extent of oxidative stress in affected joints was determined by measuring the levels of nitrotyrosine and inducible nitric oxide synthase. NF-κB activity was assayed by measuring the ratio of phosphorylated IκB to total IκB via Western blotting. Th17 cells were stained with antibodies against CD4, IL-17, and STAT3. Osteoclast formation was assessed via TRAP staining and measurement of osteoclast-specific mRNA levels.Results
In the CIA model, AEBS decreased the incidence of arthritis, histological inflammation, cartilage scores, and oxidative stress. AEBS reduced the levels of proinflammatory cytokines in affected joints of CIA mice and suppressed NF-κB signaling. AEBS decreased Th17 cell numbers in spleen of CIA mice. Additionally, AEBS repressed differentiation of Th17 cells and expression of Th17-associated genes in vitro, in both splenocytes of naïve DBA/1J mice and human PBMCs. In vitro, the numbers of both human and mouse tartrate-resistant acid phosphatase+ (TRAP) multinucleated cells fell, in a dose-dependent manner, upon addition of AEBS.Conclusions
The anti-arthritic effects of AEBS were associated with decreases in Th17 cell numbers, and the levels of proinflammatory cytokines synthesized by such cells, mediated via suppression of NF-κB signaling. Additionally, AEBS suppressed osteoclastogenesis and reduced oxidative stress levels. 相似文献42.
Lee HS Chang JH Ku SK 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2010,48(3):387-393
The regional distribution and frequency of the pancreatic endocrine cells in the ddN mouse were studied using specific antisera against insulin, glucagon, somatostatin and human pancreatic polypeptide (hPP). In the pancreatic islets, most of insulin-immunoreactive (IR) cells were located in the central region, and glucagon-, somatostatin and hPP-IR cells were located in the peripheral region regardless of the lobe. In the splenic part, glucagon-IR cells were also located in the central regions, and more numerous somatostatin-IR cells were detected in the central regions as compared with the duo-denal part. hPP-IR cells were restricted to the peripheral regions in both lobes but more numerous cells were detected in the duodenal portion. In the exocrine parenchyma of the splenic lobe, only insulin- and glucagon-IR cells were detected but all four kinds of IR cells were observed in the duodenal portion. In addition, insulin and hPP-IR cells were also demonstrated in the pancreatic duct regions. In conclusion, some strain-dependent characteristic distributional patterns of pancreatic endocrine cells were found in the ddN mouse with somewhat different distributional patterns between the two pancreatic lobes. 相似文献
43.
Tamas A. Gonda Andrea Varro Timothy C. Wang Benjamin Tycko 《Seminars in cell & developmental biology》2010,21(1):2-10
It is increasingly recognized that the non-neoplastic stromal compartment in most solid cancers plays an active role in tumor proliferation, invasion and metastasis. Cancer-associated fibroblasts (CAFs) are one of the most abundant cell types in the tumor stroma, and these cells are pro-tumorigenic. Evidence that CAFs are epigenetically and possibly also genetically distinct from normal fibroblasts is beginning to define these cells as potential targets of anti-cancer therapy. Here, we review the cell-of-origin and molecular biology of CAFs, arguing that such knowledge provides a rational basis for designing therapeutic strategies to coordinately and synergistically target both the stromal and malignant epithelial component of human cancers. 相似文献
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46.
Samantha J. Pitt Miyuki Nishi Sae Aoki Jianjie Ma Rebecca Sitsapesan 《Biophysical journal》2010,99(2):417-426
The presence of a sarcoplasmic reticulum (SR) K+-selective ion-channel has been known for >30 years yet the molecular identity of this channel has remained a mystery. Recently, an SR trimeric intracellular cation channel (TRIC-A) was identified but it did not exhibit all expected characteristics of the SR K+-channel. We show that a related SR protein, TRIC-B, also behaves as a cation-selective ion-channel. Comparison of the single-channel properties of purified TRIC-A and TRIC-B in symmetrical 210 mM K+ solutions, show that TRIC-B has a single-channel conductance of 138 pS with subconductance levels of 59 and 35 pS, whereas TRIC-A exhibits full- and subconductance open states of 192 and 129 pS respectively. We suggest that the K+-current fluctuations observed after incorporating cardiac or skeletal SR into bilayers, can be explained by the gating of both TRIC-A and TRIC-B channels suggesting that the SR K+-channel is not a single, distinct entity. Importantly, TRIC-A is regulated strongly by trans-membrane voltage whereas TRIC-B is activated primarily by micromolar cytosolic Ca2+ and inhibited by luminal Ca2+. Thus, TRIC-A and TRIC-B channels are regulated by different mechanisms, thereby providing maximum flexibility and scope for facilitating monovalent cation flux across the SR membrane. 相似文献
47.
We have cloned and characterized a novel splice variant of mouse GMx33alpha/Golgi-associated protein of 34 kDa (GPP34), hereby designated GMx33alphaV/GPP34V. This splice variant skips the second and third exons, and the resulting frame shift generates a stop codon in the fourth exon. GMx33alphaV/GPP34V is comprised of 81 amino acid residues derived from the N-terminal end of the full length protein and corresponds to approximately one-third of the full length GMx33alpha/GPP34 sequence with a calculated molecular mass of 8900. In contrast to GMx33alpha/GPP34 mRNA which is expressed at similar levels in various tissues, GMx33alphaV/GPP34V mRNA was differentially expressed when examined by RT-PCR. Compared to other tissues, skeletal muscle showed relatively strong expression of GMx33alphaV/GPP34V mRNA. This splice variant cDNA was also detected in a human cell line. 相似文献
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49.
Rhee KY de Carvalho LP Bryk R Ehrt S Marrero J Park SW Schnappinger D Venugopal A Nathan C 《Trends in microbiology》2011,19(7):307-314
Recent advances in liquid chromatography and mass spectrometry have enabled the highly parallel, quantitative measurement of metabolites within a cell and the ability to trace their biochemical fates. In Mycobacterium tuberculosis (Mtb), these advances have highlighted major gaps in our understanding of central carbon metabolism (CCM) that have prompted fresh interpretations of the composition and structure of its metabolic pathways and the phenotypes of Mtb strains in which CCM genes have been deleted. High-throughput screens have demonstrated that small chemical compounds can selectively inhibit some enzymes of Mtb's CCM while sparing homologs in the host. Mtb's CCM has thus emerged as a frontier for both fundamental and translational research. 相似文献
50.
Trokovic N Gonda A Herczeg G Laurila A Merilä J 《Journal of evolutionary biology》2011,24(6):1380-1385
Brain development shows high plasticity in response to environmental heterogeneity. However, it is unknown how environmental variation during development may affect brain architecture across life history switch points in species with complex life cycles. Previously, we showed that predation and competition affect brain development in common frog (Rana temporaria) tadpoles. Here, we studied whether larval environment had carry-over effects in brains of metamorphs. Tadpoles grown at high density had large optic tecta at metamorphosis, whereas tadpoles grown under predation risk had small diencephala. We found that larval density had a carry-over effect on froglet optic tectum size, whereas the effect of larval predation risk had vanished by metamorphosis. We discuss the possibility that the observed changes may be adaptive, reflecting the needs of an organism in given environmental and developmental contexts. 相似文献