Identification of a new adtrp1-tfpi regulatory axis for the specification of primitive myelopoiesis and definitive hematopoiesis [Research]
A genomic variant in the human ADTRP [androgen-dependent tissue factor (TF) pathway inhibitor (TFPI) regulating protein] gene increases the risk of coronary artery disease, the leading cause of death worldwide. TFPI is the TF pathway inhibitor that is involved in coagulation. Here, we report that adtrp and tfpi form a regulatory axis that specifies primitive myelopoiesis and definitive hematopoiesis, but not primitive erythropoiesis or vasculogenesis. In zebrafish, there are 2 paralogues for adtrp (i.e., adtrp1 and adtrp2). Knockdown of adtrp1 expression inhibits the specification of hemangioblasts, as shown by decreased e...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Wang, L., Wang, X., Wang, L., Yousaf, M., Li, J., Zuo, M., Yang, Z., Gou, D., Bao, B., Li, L., Xiang, N., Jia, H., Xu, C., Chen, Q., Wang, Q. K. Tags: Research Source Type: research
Real-time acquisition of transendothelial electrical resistance in an all-human, in vitro, 3-dimensional, blood-brain barrier model exemplifies tight-junction integrity [Research]
The blood–brain barrier (BBB) consists of endothelial cells, astrocytes, and pericytes embedded in basal lamina (BL). Most in vitro models use nonhuman, monolayer cultures for therapeutic-delivery studies, relying on transendothelial electrical resistance (TEER) measurements without other tight-junction (TJ) formation parameters. We aimed to develop reliable, reproducible, in vitro 3-dimensional (3D) models incorporating relevant human, in vivo cell types and BL proteins. The 3D BBB models were constructed with human brain endothelial cells, human astrocytes, and human brain pericytes in mono-, co-, and tricultures. ...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Maherally, Z., Fillmore, H. L., Tan, S. L., Tan, S. F., Jassam, S. A., Quack, F. I., Hatherell, K. E., Pilkington, G. J. Tags: Research Source Type: research
Protease-activated receptor 2 activates airway apical membrane chloride permeability and increases ciliary beating [Research]
In this study, we examined the protease-activated receptor (PAR)-2, a GPCR previously shown to regulate airway cell cytokine and mucus secretion, and transepithelial Cl– current. PAR-2 is activated by proteases secreted by airway neutrophils and pathogens. We cultured various airway cell lines, primary human and mouse sinonasal cells, and human bronchial cells at air–liquid interface and examined them using molecular biology, biochemistry, and live-cell imaging. We found that PAR-2 is expressed basolaterally, where it stimulates both intracellular Ca2+ release and Ca2+ influx, which activates low-level nitric o...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: McMahon, D. B., Workman, A. D., Kohanski, M. A., Carey, R. M., Freund, J. R., Hariri, B. M., Chen, B., Doghramji, L. J., Adappa, N. D., Palmer, J. N., Kennedy, D. W., Lee, R. J. Tags: Research Source Type: research
Cathepsin B-mediated CD18 shedding regulates leukocyte recruitment from angiogenic vessels [Research]
Cathepsin B (CtsB) contributes to atherosclerosis and cancer progression by processing the extracellular matrix and promoting angiogenesis. Although CtsB was reported to promote and reduce angiogenesis, there is no mechanistic explanation that reconciles this apparent discrepancy. CtsB cleaves CD18 from the surface of immune cells, but its contribution to angiogenesis has not been studied. We developed an in vivo technique for visualization of immune cell transmigration from corneal vessels toward implanted cytokines. Wild-type (WT) leukocytes extravasated from limbal vessels, angiogenic stalks, and growing tip vessels and...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Nakao, S., Zandi, S., Sun, D., Hafezi-Moghadam, A. Tags: Research Source Type: research
A novel role for ceramide synthase 6 in mouse and human alcoholic steatosis [Research]
We examined the effects of pharmacologic ceramide synthesis inhibition on hepatic PLIN2 expression, steatosis, and glucose and lipid homeostasis in mice with alcoholic steatosis and in ethanol-incubated human hepatoma VL17A cells. In cells, pharmacologic inhibition of ceramide synthase reduced lipid accumulation by reducing PLIN2 RNA stability. The subtype ceramide synthase (CerS)6 was specifically up-regulated in experimental alcoholic steatosis in vivo and in vitro and was up-regulated in zone 3 hepatocytes in human alcoholic steatosis. In vivo ceramide reduction by inhibition of de novo ceramide synthesis reduced PLIN2 ...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Williams, B., Correnti, J., Oranu, A., Lin, A., Scott, V., Annoh, M., Beck, J., Furth, E., Mitchell, V., Senkal, C. E., Obeid, L., Carr, R. M. Tags: Research Source Type: research
Experimental confirmation of the C3 tickover hypothesis by studies with an Ab (S77) that inhibits tickover in whole serum [Research]
The complement component 3 (C3) tickover hypothesis was put forward in the early 1970s to account for the spontaneous activation of the alternative complement pathway that occurs after the genetic absence or in vitro depletion of Factor I, the enzyme that is essential for the breakdown of C3b. The hypothesis was widely accepted, but experimental demonstration of the tickover was elusive. A phage Ab against C3b that inhibited the alternative complement pathway, but not the classical pathway, was described in 2009. Studies using this Ab in a variety of assays have now demonstrated that it acts primarily by inhibiting tickove...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Lachmann, P. J., Lay, E., Seilly, D. J. Tags: Research Source Type: research
In vitro and in vivo imaging and tracking of intestinal organoids from human induced pluripotent stem cells [Research]
Human intestinal organoids (hIOs) derived from human pluripotent stem cells (hPSCs) have immense potential as a source of intestines. Therefore, an efficient system is needed for visualizing the stage of intestinal differentiation and further identifying hIOs derived from hPSCs. Here, 2 fluorescent biosensors were developed based on human induced pluripotent stem cell (hiPSC) lines that stably expressed fluorescent reporters driven by intestine-specific gene promoters Krüppel-like factor 5 monomeric Cherry (KLF5mCherry) and intestine-specific homeobox enhanced green fluorescence protein (ISXeGFP). Then hIOs were ef...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Jung, K. B., Lee, H., Son, Y. S., Lee, J. H., Cho, H.-S., Lee, M.-O., Oh, J.-H., Lee, J., Kim, S., Jung, C.-R., Kim, J., Son, M.-Y. Tags: Research Source Type: research
Exosomes in postshock mesenteric lymph are key mediators of acute lung injury triggering the macrophage activation via Toll-like receptor 4 [Research]
Acute lung injury (ALI) is a common cause of morbidity in patients after severe injury due to dysregulated inflammation, which is believed to be driven by gut-derived inflammatory mediators carried via mesenteric lymph (ML). We have previously demonstrated that nano-sized extracellular vesicles, called exosomes, secreted into ML after trauma/hemorrhagic shock (T/HS) have the potential to activate immune cells in vitro. Here, we assess the function of ML exosomes in the development of T/HS-induced ALI and the role of TLR4 in the ML exosome–mediated inflammatory response. ML exosomes isolated from rats subjected to T/H...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Kojima, M., Gimenes-Junior, J. A., Chan, T. W., Eliceiri, B. P., Baird, A., Costantini, T. W., Coimbra, R. Tags: Research Source Type: research
Normoxic cells remotely regulate the acid-base balance of cells at the hypoxic core of connexin-coupled tumor growths [Research]
ATP fuels the removal of metabolic end-products, including H+ ions that profoundly modulate biological activities. Energetic resources in hypoxic tumor regions are constrained by low-yielding glycolysis, and any means of reducing the cost of acid extrusion, without compromising pH homeostasis, would therefore be advantageous for cancer cells. Some cancers express connexin channels that allow solute exchange between cells, and we propose that, via this route, normoxic cells supply hypoxic neighbors with acid-neutralizing HCO3– ions. This hypothesis was tested by imaging cytoplasmic pH in spheroidal tissue growths of c...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Dovmark, T. H., Hulikova, A., Niederer, S. A., Vaughan-Jones, R. D., Swietach, P. Tags: Research Source Type: research
Switching of the substrate specificity of protein tyrosine phosphatase N12 by cyclin-dependent kinase 2 phosphorylation orchestrating 2 oncogenic pathways [Research]
The protein tyrosine phosphatase nonreceptor type 12 (PTPN12) is a multifunctional protein and has elicited much research attention because its decreased protein level has been associated with poor prognosis of several types of cancers. Recently, we have solved the crystal structure of the phosphatase domain of PTPN12, which disclosed a specific PTPN12–insert–loop harboring a cyclin-dependent kinase 2 (CDK2) phosphorylation site. However, the functional significance of this phosphorylation is undefined. In the present study, we found that S19 site phosphorylation of PTPN12 by CDK2 discharged its antitumor activ...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Li, H., Yang, D., Ning, S., Xu, Y., Yang, F., Yin, R., Feng, T., Han, S., Guo, L., Zhang, P., Qu, W., Guo, R., Song, C., Xiao, P., Zhou, C., Xu, Z., Sun, J.-P., Yu, X. Tags: Research Source Type: research
Testicular cells exhibit similar molecular responses to cigarette smoke condensate ex vivo and in vivo [Research]
Male exposure to cigarette smoke is associated with seminal defects and with congenital anomalies and childhood cancers in offspring. In mice, paternal exposure to cigarette smoke condensate (CSC) causes molecular defects in germ cells and phenotypic effects in their offspring. Here we used an ex vivo testicular explant model and in vivo exposure to determine the concentration at which CSC impairs spermatogenesis and offspring development. We explanted testis tissue at postnatal day (P)5.5 and cultured it until P11.5. Assessment of growth parameters by analyzing expression of cell-specific markers revealed that the explant...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Esakky, P., Hansen, D. A., Drury, A. M., Felder, P., Cusumano, A., Moley, K. H. Tags: Research Source Type: research
Proteasome inhibitor bortezomib is a novel therapeutic agent for focal radiation-induced osteoporosis [Research]
Bone atrophy and its related fragility fractures are frequent, late side effects of radiotherapy in cancer survivors and have a detrimental impact on their quality of life. In another study, we showed that parathyroid hormone 1-34 and anti-sclerostin antibody attenuates radiation-induced bone damage by accelerating DNA repair in osteoblasts. DNA damage responses are partially regulated by the ubiquitin proteasome pathway. In the current study, we examined whether proteasome inhibitors have similar bone-protective effects against radiation damage. MG132 treatment greatly reduced radiation-induced apoptosis in cultured osteo...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Chandra, A., Wang, L., Young, T., Zhong, L., Tseng, W.-J., Levine, M. A., Cengel, K., Liu, X. S., Zhang, Y., Pignolo, R. J., Qin, L. Tags: Research Source Type: research
Defective lysosomal clearance of autophagosomes and its clinical implications in nonalcoholic steatohepatitis [Research]
Autophagic impairment is implicated in nonalcoholic fatty liver disease (NAFLD), but the molecular mechanism is unclear. We found that autophagic flux was significantly inhibited in 3 murine models of NAFLD. Interestingly, the number of acidic organelles and the level of mature cathepsin D were reduced, suggesting defective lysosome acidification. Asparagine synthetase (ASNS) was induced by endoplasmic reticulum stress, leading to the generation of asparagine, which inhibited lysosome acidification. Both steatotic- and asparagine-treated hepatocytes showed reduced lysosomal acidity and retention of lysosomal calcium. Knock...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Wang, X., Zhang, X., Chu, E. S. H., Chen, X., Kang, W., Wu, F., To, K.-F., Wong, V. W. S., Chan, H. L. Y., Chan, M. T. V., Sung, J. J. Y., Wu, W. K. K., Yu, J. Tags: Research Source Type: research
Formyl-peptide receptor 2 governs leukocyte influx in local Staphylococcus aureus infections [Research]
Leukocytes express formyl-peptide receptors (FPRs), which sense microbe-associated molecular pattern (MAMP) molecules, leading to leukocyte chemotaxis and activation. We recently demonstrated that phenol-soluble modulin (PSM) peptides from highly pathogenic Staphylococcus aureus are efficient ligands for the human FPR2. How PSM detection by FPR2 impacts on the course of S. aureus infections has remained unknown. We characterized the specificity of mouse FPR2 (mFpr2) using a receptor-transfected cell line, homeobox b8 (Hoxb8), and primary neutrophils isolated from wild-type (WT) or mFpr2–/– mice. The influx of l...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Weiss, E., Hanzelmann, D., Fehlhaber, B., Klos, A., von Loewenich, F. D., Liese, J., Peschel, A., Kretschmer, D. Tags: Research Source Type: research
PLA2 and ENPP6 may act in concert to generate phosphocholine from the matrix vesicle membrane during skeletal mineralization [Hypothesis]
Mineralization is a key process in the formation of bone and cartilage in vertebrates, involving the deposition of calcium- and phosphate-containing hydroxyapatite (HA) mineral within a collagenous matrix. Inorganic phosphate (Pi) accumulation within matrix vesicles (MVs) is a fundamental stage in the precipitation of HA, with PHOSPHO1 being identified as the principal enzyme acting to produce Pi. PHOSPHO1 is a dual-specific phosphocholine/phosphoethanolamine phosphatase enriched in mineralizing cells and within MVs. However, the source and mechanism by which PHOSPHO1 substrates are formed before mineralization have not be...
Source: FASEB Journal - January 2, 2018 Category: Biology Authors: Stewart, A. J., Leong, D. T. K., Farquharson, C. Tags: Hypothesis Source Type: research
