160 research outputs found
Hydrogen peroxide is a diffusible paracrine signal for the induction of epithelial cell death by activated myofibroblasts
Cellâcell signaling roles for reactive oxygen species (ROS) generated in response to growth factors/cytokines in nonphagocytic cells are not well defined. In this study, we show that fibroblasts isolated from lungs of patients with idiopathic pulmonary fibrosis (IPF) generate extracellular hydrogen peroxide (H2O2) in response to the multifunctional cytokine, transforming growth factorâβ1 (TGFâβ1). In contrast, TGFâβ1 stimulation of small airway epithelial cells (SAECs) does not result in detectable levels of extracellular H2O2. IPF fibroblasts independently stimulated with TGFâβ1 induce loss of viability and death of overlying SAECs when cocultured in a compartmentalized Transwell system. These effects on SAECs are inhibited by the addition of catalase to the coculture system or by the selective enzymatic blockade of H2O2 production by IPF fibroblasts. IPF fibroblasts heterogeneously express Îąâsmooth muscle actin stress fibers, a marker of myofibroblast differentiation. Cellular localization of H2O2 by a fluorescentâlabeling strategy demonstrated that extracellular secretion of H2O2 is specific to the myofibroblast phenotype. Thus, myofibroblast secretion of H2O2 functions as a diffusible death signal for lung epithelial cells. This novel mechanism for intercellular ROS signaling may be important in physiological/pathophysiological processes characterized by regenerating epithelial cells and activated myofibroblasts.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154383/1/fsb2fj042882fje.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154383/2/fsb2fj042882fje-sup-0001.pd
NNZ-2566 treatment inhibits neuroinflammation and pro-inflammatory cytokine expression induced by experimental penetrating ballistic-like brain injury in rats
<p>Abstract</p> <p>Background</p> <p>Inflammatory cytokines play a crucial role in the pathophysiology of traumatic brain injury (TBI), exerting either deleterious effects on the progression of tissue damage or beneficial roles during recovery and repair. NNZ-2566, a synthetic analogue of the neuroprotective tripeptide Glypromate<sup>Ž</sup>, has been shown to be neuroprotective in animal models of brain injury. The goal of this study was to determine the effects of NNZ-2566 on inflammatory cytokine expression and neuroinflammation induced by penetrating ballistic-like brain injury (PBBI) in rats.</p> <p>Methods</p> <p>NNZ-2566 or vehicle (saline) was administered intravenously as a bolus injection (10 mg/kg) at 30 min post-injury, immediately followed by a continuous infusion of NNZ-2566 (3 mg/kg/h), or equal volume of vehicle, for various durations. Inflammatory cytokine gene expression from the brain tissue of rats exposed to PBBI was evaluated using microarray, quantitative real time PCR (QRT-PCR), and enzyme-linked immunosorbent assay (ELISA) array. Histopathology of the injured brains was examined using hematoxylin and eosin (H&E) and immunocytochemistry of inflammatory cytokine IL-1β.</p> <p>Results</p> <p>NNZ-2566 treatment significantly reduced injury-mediated up-regulation of IL-1β, TNF-ι, E-selectin and IL-6 mRNA during the acute injury phase. ELISA cytokine array showed that NZ-2566 treatment significantly reduced levels of the pro-inflammatory cytokines IL-1β, TNF-ι and IFN-γ in the injured brain, but did not affect anti-inflammatory cytokine IL-6 levels.</p> <p>Conclusion</p> <p>Collectively, these results suggest that the neuroprotective effects of NNZ-2566 may, in part, be functionally attributed to the compound's ability to modulate expression of multiple neuroinflammatory mediators in the injured brain.</p
Proteins associated with pancreatic cancer survival in patients with resectable pancreatic ductal adenocarcinoma.
Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease with a dismal prognosis. However, while most patients die within the first year of diagnosis, very rarely, a few patients can survive for >10 years. Better understanding the molecular characteristics of the pancreatic adenocarcinomas from these very-long-term survivors (VLTS) may provide clues for personalized medicine and improve current pancreatic cancer treatment. To extend our previous investigation, we examined the proteomes of individual pancreas tumor tissues from a group of VLTS patients (survival âĽ10 years) and short-term survival patients (STS, survival <14 months). With a given analytical sensitivity, the protein profile of each pancreatic tumor tissue was compared to reveal the proteome alterations that may be associated with pancreatic cancer survival. Pathway analysis of the differential proteins identified suggested that MYC, IGF1R and p53 were the top three upstream regulators for the STS-associated proteins, and VEGFA, APOE and TGFβ-1 were the top three upstream regulators for the VLTS-associated proteins. Immunohistochemistry analysis using an independent cohort of 145 PDAC confirmed that the higher abundance of ribosomal protein S8 (RPS8) and prolargin (PRELP) were correlated with STS and VLTS, respectively. Multivariate Cox analysis indicated that 'High-RPS8 and Low-PRELP' was significantly associated with shorter survival time (HR=2.69, 95% CI 1.46-4.92, P=0.001). In addition, galectin-1, a previously identified protein with its abundance aversely associated with pancreatic cancer survival, was further evaluated for its significance in cancer-associated fibroblasts. Knockdown of galectin-1 in pancreatic cancer-associated fibroblasts dramatically reduced cell migration and invasion. The results from our study suggested that PRELP, LGALS1 and RPS8 might be significant prognostic factors, and RPS8 and LGALS1 could be potential therapeutic targets to improve pancreatic cancer survival if further validated
PROCESS STANDARDIZATION AND EVALUATION OF GREEN PEAS (PISUM SATIVUM) USING SOLAR DEHYDRATION TECHNOLOGY
Fruits and vegetables play an important role in human nutrition, but due to their high perishable nature they cannot be stored for longer period. To store for long period, dehydration is one of the techniques developed which can persist for longer periods and are said to be rich sources of vitamins, minerals and anti-oxidants. Emerging trends in food processing is one of the major aspects in recent times, where the present study is to utilize the importance of value addition to improve the nutritive value of food product and increase the efficiency of its processing. Hence solar dehydration technology was found to be an efficient process having less energy consumption and maximum retention of nutritive value. The objective of this study is to standardize the pretreatment for maximum chlorophyll retention of green peas and evaluation of the standardized product using solar dehydration technology. With this objective, the process procedure for green peas was standardized where 0.1% sodium bicarbonate and 0.1% magnesium oxide were used in water blanching for 4min. Solar dehydrated green peas were developed with 10 sunny hours (490c-510c) of drying time with a yield of 11.758% and moisture content 5.788%. The dried products were packed in two different packaging materials i.e., Aluminium and Polypropylene pouches. Shelf life studies were conducted at ambient and accelerated storage conditions in two different packaging materials for about 6 months. The results revealed that the solar dried green peas which were pretreated with 0.1% sodium bicarbonate and 0.1% magnesium oxide solution and packed in Aluminium pouch have retained most of the nutrients viz., Vitamin C, Chlorophyll content, and physico chemical properties. Sensory evaluation of dried green peas showed that color and flavor were superior in Aluminium pouch when compared with the product packed in polypropylene pouch. Microbial load was also within the limits, which indicated that the product can be shelf stable for a period of 6 months. The dehydrated green peas are rehydrated and used in pulav, upma, biryani
Viral GPCR US28 can signal in response to chemokine agonists of nearly unlimited structural degeneracy
Structural basis for chemokine recognition and activation of a viral G protein-coupled receptor
Chemokines are small proteins that function as immune modulators through activation of chemokine G proteinâcoupled receptors (GPCRs). Several viruses also encode chemokines and chemokine receptors to subvert the host immune response. How protein ligands activate GPCRs remains unknown. We report the crystal structure at 2.9 angstrom resolution of the human cytomegalovirus GPCR US28 in complex with the chemokine domain of human CX3CL1 (fractalkine). The globular body of CX3CL1 is perched on top of the US28 extracellular vestibule, whereas its amino terminus projects into the central core of US28. The transmembrane helices of US28 adopt an active-stateâlike conformation. Atomic-level simulations suggest that the agonist-independent activity of US28 may be due to an amino acid network evolved in the viral GPCR to destabilize the receptorâs inactive state.Swiss National Science FoundationNational Institutes of Health (U.S.) (Pioneer Award)Virginia and D.K. Ludwig Fund for Cancer Researc
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Structure of human frizzled5 by fiducial-assisted cryo-em supports a heterodimeric mechanism of canonical wnt signaling
Frizzleds (Fzd) are the primary receptors for Wnt morphogens, which are essential regulators of stem cell biology, yet the structural basis of Wnt signaling through Fzd remains poorly understood. Here we report the structure of an unliganded human Fzd5 determined by single-particle cryo-EM at 3.7 Ă
resolution, with the aid of an antibody chaperone acting as a fiducial marker. We also analyzed the topology of low-resolution XWnt8/Fzd5 complex particles, which revealed extreme flexibility between the Wnt/Fzd-CRD and the Fzd-TM regions. Analysis of Wnt/b-catenin signaling in response to Wnt3a versus a âsurrogate agonistâ that cross-links Fzd to LRP6, revealed identical structure-activity relationships. Thus, canonical Wnt/b-catenin signaling appears to be principally reliant on ligand-induced Fzd/LRP6 heterodimerization, versus the allosteric mechanisms seen in structurally analogous class A G protein-coupled receptors, and Smoothened. These findings deepen our mechanistic understanding of Wnt signal transduction, and have implications for harnessing Wnt agonism in regenerative medicine
Mechanisms of pulmonary fibrosis: role of activated myofibroblasts and NADPH oxidase
A common feature of pathological fibrosis involving the lung and other organs is the persistent activation of myofibroblasts in injured tissues. Recent evidence supports the role of a member of the NADPH oxidase (NOX) gene family, NOX4, in myofibroblast differentiation, matrix synthesis and contractility. Additionally, NOX4 may contribute directly or indirectly to alveolar epithelial cell death, while myofibroblasts themselves acquire an apoptosis-resistant phenotype. Thus, NOX4 may be responsible for the cardinal features of progressive fibrosis - myofibroblast activation and epithelial cell dysrepair. Therapeutic targeting of NOX4 is likely to be effective in progressive cases of fibrosis involving multiple organs
The Human Lung Cell Atlas: A High-Resolution Reference Map of the Human Lung in Health and Disease.
Lung disease accounts for every sixth death globally. Profiling the molecular state of all lung cell types in health and disease is currently revolutionizing the identification of disease mechanisms and will aid the design of novel diagnostic and personalized therapeutic regimens. Recent progress in high-throughput techniques for single-cell genomic and transcriptomic analyses has opened up new possibilities to study individual cells within a tissue, classify these into cell types, and characterize variations in their molecular profiles as a function of genetics, environment, cell-cell interactions, developmental processes, aging, or disease. Integration of these cell state definitions with spatial information allows the in-depth molecular description of cellular neighborhoods and tissue microenvironments, including the tissue resident structural and immune cells, the tissue matrix, and the microbiome. The Human Cell Atlas consortium aims to characterize all cells in the healthy human body and has prioritized lung tissue as one of the flagship projects. Here, we present the rationale, the approach, and the expected impact of a Human Lung Cell Atlas.Supported by the Helmholtz Association and the German Center for Lung Research (DZL) (H.B.S.); the European Unionâs Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement 753039 (L.M.S.); U.K. Medical Research Council grant G0900424 (E.L.R.); National Institutes of Health (NIH) grants ES013995, HL071643, and AG049665, and Veterans Administration grant BX000201 and Department of Defense grant PR141319 (G.R.S.B.); NIH grants HL135124 and AI135964 and Department of Defense grant PR141319 (A.V.M.); NIH grants R01HL141852, R01HL127349, UHHL3123886, U01HL122626, and UG3TR002445, and Department of Defence grant PR151124 (N.K.); and the Netherlands Lung Foundation grants 5.1.14.020 and 4.1.18.226 (M.C.N.)
Proteomic Interrogation of Androgen Action in Prostate Cancer Cells Reveals Roles of Aminoacyl tRNA Synthetases
Prostate cancer remains the most common malignancy among men in United States, and there is no remedy currently available for the advanced stage hormone-refractory cancer. This is partly due to the incomplete understanding of androgen-regulated proteins and their encoded functions. Whole-cell proteomes of androgen-starved and androgen-treated LNCaP cells were analyzed by semi-quantitative MudPIT ESI- ion trap MS/MS and quantitative iTRAQ MALDI- TOF MS/MS platforms, with identification of more than 1300 high-confidence proteins. An enrichment-based pathway mapping of the androgen-regulated proteomic data sets revealed a significant dysregulation of aminoacyl tRNA synthetases, indicating an increase in protein biosynthesis- a hallmark during prostate cancer progression. This observation is supported by immunoblot and transcript data from LNCaP cells, and prostate cancer tissue. Thus, data derived from multiple proteomics platforms and transcript data coupled with informatics analysis provides a deeper insight into the functional consequences of androgen action in prostate cancer
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