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81.
Rosa Spinelli Pasqualina Florese Luca Parrillo Federica Zatterale Michele Longo Vittoria DEsposito Antonella Desiderio Annika Nerstedt Birgit Gustafson Pietro Formisano Claudia Miele Gregory Alexander Raciti Raffaele Napoli Ulf Smith Francesco Beguinot 《Aging cell》2022,21(3)
Senescence of adipose precursor cells (APC) impairs adipogenesis, contributes to the age‐related subcutaneous adipose tissue (SAT) dysfunction, and increases risk of type 2 diabetes (T2D). First‐degree relatives of T2D individuals (FDR) feature restricted adipogenesis, reflecting the detrimental effects of APC senescence earlier in life and rendering FDR more vulnerable to T2D. Epigenetics may contribute to these abnormalities but the underlying mechanisms remain unclear. In previous methylome comparison in APC from FDR and individuals with no diabetes familiarity (CTRL), ZMAT3 emerged as one of the top‐ranked senescence‐related genes featuring hypomethylation in FDR and associated with T2D risk. Here, we investigated whether and how DNA methylation changes at ZMAT3 promote early APC senescence. APC from FDR individuals revealed increases in multiple senescence markers compared to CTRL. Senescence in these cells was accompanied by ZMAT3 hypomethylation, which caused ZMAT3 upregulation. Demethylation at this gene in CTRL APC led to increased ZMAT3 expression and premature senescence, which were reverted by ZMAT3 siRNA. Furthermore, ZMAT3 overexpression in APC determined senescence and activation of the p53/p21 pathway, as observed in FDR APC. Adipogenesis was also inhibited in ZMAT3‐overexpressing APC. In FDR APC, rescue of ZMAT3 methylation through senolytic exposure simultaneously downregulated ZMAT3 expression and improved adipogenesis. Interestingly, in human SAT, aging and T2D were associated with significantly increased expression of both ZMAT3 and the P53 senescence marker. Thus, DNA hypomethylation causes ZMAT3 upregulation in FDR APC accompanied by acquisition of the senescence phenotype and impaired adipogenesis, which may contribute to FDR predisposition for T2D. 相似文献
82.
Willens S Stoskopf MK Martin LD Lewbart GA 《In vitro cellular & developmental biology. Animal》2005,41(8-9):258-263
Summary Anurans are important animal models for studying the effects of anthropogenic chemical contamination of the environment. Two-compartment
Teflon flow-through diffusion cells can be used to study percutaneus absorption of xenobiotics across harvested skin. However,
such an approach currently necessitates that skin be harvested just before experimentation, a requirement that calls for the
continuous growth and housing of living animals. The ability to preserve and store skin would allow more efficient use of
animals and more flexibility in experimental design. To this end, we examined the viability of harvested anuran skin stored
under various protocols consistent with current practices of mammalian skin preservation. Skin from the American bullfrog
maintained 80–85% viability after 28 d, whereas viability of skin from the marine toad was only maintained for 7–10 d. 相似文献
83.
Biswas S Nyman JS Alvarez J Chakrabarti A Ayres A Sterling J Edwards J Rana T Johnson R Perrien DS Lonning S Shyr Y Matrisian LM Mundy GR 《PloS one》2011,6(11):e27090
Breast cancer often metastasizes to bone causing osteolytic bone resorption which releases active TGFβ. Because TGFβ favors progression of breast cancer metastasis to bone, we hypothesized that treatment using anti-TGFβ antibody may reduce tumor burden and rescue tumor-associated bone loss in metastatic breast cancer. In this study we have tested the efficacy of an anti-TGFβ antibody 1D11 preventing breast cancer bone metastasis. We have used two preclinical breast cancer bone metastasis models, in which either human breast cancer cells or murine mammary tumor cells were injected in host mice via left cardiac ventricle. Using several in vivo, in vitro and ex vivo assays, we have demonstrated that anti-TGFβ antibody treatment have significantly reduced tumor burden in the bone along with a statistically significant threefold reduction in osteolytic lesion number and tenfold reduction in osteolytic lesion area. A decrease in osteoclast numbers (p?=?0.027) in vivo and osteoclastogenesis ex vivo were also observed. Most importantly, in tumor-bearing mice, anti-TGFβ treatment resulted in a twofold increase in bone volume (p<0.01). In addition, treatment with anti-TGFβ antibody increased the mineral-to-collagen ratio in vivo, a reflection of improved tissue level properties. Moreover, anti-TGFβ antibody directly increased mineralized matrix formation in calverial osteoblast (p?=?0.005), suggesting a direct beneficial role of anti-TGFβ antibody treatment on osteoblasts. Data presented here demonstrate that anti-TGFβ treatment may offer a novel therapeutic option for tumor-induced bone disease and has the dual potential for simultaneously decreasing tumor burden and rescue bone loss in breast cancer to bone metastases. This approach of intervention has the potential to reduce skeletal related events (SREs) in breast cancer survivors. 相似文献
84.
Ali Sadeghi-Naini Ervis Sofroni Naum Papanicolau Omar Falou Linda Sugar Gerard Morton Martin J. Yaffe Robert Nam Alireza Sadeghian Michael C. Kolios Hans T. Chung Gregory J. Czarnota 《Translational oncology》2015,8(1):25-34
Three-dimensional quantitative ultrasound spectroscopic imaging of prostate was investigated clinically for the noninvasive detection and extent characterization of disease in cancer patients and compared to whole-mount, whole-gland histopathology of radical prostatectomy specimens. Fifteen patients with prostate cancer underwent a volumetric transrectal ultrasound scan before radical prostatectomy. Conventional-frequency (~ 5 MHz) ultrasound images and radiofrequency data were collected from patients. Normalized power spectra were used as the basis of quantitative ultrasound spectroscopy. Specifically, color-coded parametric maps of 0-MHz intercept, midband fit, and spectral slope were computed and used to characterize prostate tissue in ultrasound images. Areas of cancer were identified in whole-mount histopathology specimens, and disease extent was correlated to that estimated from quantitative ultrasound parametric images. Midband fit and 0-MHz intercept parameters were found to be best associated with the presence of disease as located on histopathology whole-mount sections. Obtained results indicated a correlation between disease extent estimated noninvasively based on midband fit parametric images and that identified histopathologically on prostatectomy specimens, with an r2 value of 0.71 (P < .0001). The 0-MHz intercept parameter demonstrated a lower level of correlation with histopathology. Spectral slope parametric maps offered no discrimination of disease. Multiple regression analysis produced a hybrid disease characterization model (r2 = 0.764, P < .05), implying that the midband fit biomarker had the greatest correlation with the histopathologic extent of disease. This work demonstrates that quantitative ultrasound spectroscopic imaging can be used for detecting prostate cancer and characterizing disease extent noninvasively, with corresponding gross three-dimensional histopathologic correlation. 相似文献
85.
86.
Thomas Vedvick Richard G. Buckholz Michael Engel Mary Urcan Jennifer Kinney Sally Provow Robert S. Siegel Gregory P. Thill 《Journal of industrial microbiology & biotechnology》1991,7(3):197-201
Summary A synthetic gene encoding aprotinin (bovine pancreatic trypsin, inhibitor) was fused to theSaccharomyces cerevisiae prepro alpha mating factor leader sequence at the dibasic amino acid processing site.Pichia pastoris strains were developed to'express one or multiple copies of a methanol-inducible expression cassette containing the gene fusion.P. pastoris containing a single copy of the vector secreed approximately 150 mg/l of immunoreactive protein. A construct bearing five copies of the expression cassette secreted 930 mg/l of aprotinin. The purified aprotinin molecule was equipoten with the native molecule in a trypsin inhibition assay. Protein sequence analysis showed that the alpha factor-aprotinin fusion was not processed at the basic amino acid residues Lys-Arg. Instead, recombinant aprotinin had additional N-terminal amino acids derived from prepro alpha factor. The N-terminal extension was variably 11 or 4 amino acids. Inclusion of the spacer DNA sequence encoding Glu and Ala between aprotinin and the Lys-Arg processing site led to the secretion of a biologically active aprotinin containing only a Glu-Ala N-terminal extension. 相似文献
87.
88.
GS Basarab P Hill CJ Eyermann M Gowravaram H Käck E Osimoni 《Bioorganic & medicinal chemistry letters》2012,22(17):5600-5607
Structure-activity relationships are presented around a series of pyrazolopyrimidinediones that inhibit the growth of Helicobacter pylori by targeting glutamate racemase, an enzyme that provides d-glutamate for the construction of N-acetylglucosamine-N-acetylmuramic acid peptidoglycan subunits assimilated into the bacterial cell wall. Substituents on the inhibitor scaffold were varied to optimize target potency, antibacterial activity and in vivo pharmacokinetic stability. By incorporating an imidazole ring at the 7-position of scaffold, high target potency was achieved due to a hydrogen bonding network that occurs between the 3-position nitrogen atom, a bridging water molecule and the side chains Ser152 and Trp244 of the enzyme. The lipophilicity of the scaffold series proved important for expression of antibacterial activity. Clearances in vitro and in vivo were monitored to identify compounds with improved plasma stability. The basicity of the imidazole may contribute to increased aqueous solubility at lower pH allowing for improved oral bioavailability. 相似文献
89.
Natalia J. Martinez Ganesha Rai Adam Yasgar Wendy A. Lea Hongmao Sun Yuhong Wang Diane K. Luci Shyh-Ming Yang Kana Nishihara Shunichi Takeda Mohiuddin Irina Earnshaw Tetsuya Okada Kazutoshi Mori Kelli Wilson Gregory J. Riggins Menghang Xia Maurizio Grimaldi Ajit Jadhav David J. Maloney Anton Simeonov 《PloS one》2016,11(11)
90.
Wendy J. van Zuylen Priscilla Doyon Jean-Fran?ois Clément Kashif Aziz Khan Lisa M. D'Ambrosio Florence D? Myriam St-Amant-Verret Tasheen Wissanji Gregory Emery Anne-Claude Gingras Sylvain Meloche Marc J. Servant 《PLoS pathogens》2012,8(7)
Tumor Necrosis Factor receptor-associated factor-3 (TRAF3) is a central mediator important for inducing type I interferon (IFN) production in response to intracellular double-stranded RNA (dsRNA). Here, we report the identification of Sec16A and p115, two proteins of the ER-to-Golgi vesicular transport system, as novel components of the TRAF3 interactome network. Notably, in non-infected cells, TRAF3 was found associated with markers of the ER-Exit-Sites (ERES), ER-to-Golgi intermediate compartment (ERGIC) and the cis-Golgi apparatus. Upon dsRNA and dsDNA sensing however, the Golgi apparatus fragmented into cytoplasmic punctated structures containing TRAF3 allowing its colocalization and interaction with Mitochondrial AntiViral Signaling (MAVS), the essential mitochondria-bound RIG-I-like Helicase (RLH) adaptor. In contrast, retention of TRAF3 at the ER-to-Golgi vesicular transport system blunted the ability of TRAF3 to interact with MAVS upon viral infection and consequently decreased type I IFN response. Moreover, depletion of Sec16A and p115 led to a drastic disorganization of the Golgi paralleled by the relocalization of TRAF3, which under these conditions was unable to associate with MAVS. Consequently, upon dsRNA and dsDNA sensing, ablation of Sec16A and p115 was found to inhibit IRF3 activation and anti-viral gene expression. Reciprocally, mild overexpression of Sec16A or p115 in Hec1B cells increased the activation of IFNβ, ISG56 and NF-κB -dependent promoters following viral infection and ectopic expression of MAVS and Tank-binding kinase-1 (TBK1). In line with these results, TRAF3 was found enriched in immunocomplexes composed of p115, Sec16A and TBK1 upon infection. Hence, we propose a model where dsDNA and dsRNA sensing induces the formation of membrane-bound compartments originating from the Golgi, which mediate the dynamic association of TRAF3 with MAVS leading to an optimal induction of innate immune responses. 相似文献