A5038155532- Adenosine and Purinergic Signaling
- Inflammasome and immune disorders
- Neuroscience of respiration and sleep
- Ion channel regulation and function
- Neonatal Health and Biochemistry
- Nitric Oxide and Endothelin Effects
- Heme Oxygenase-1 and Carbon Monoxide
- Immune Cell Function and Interaction
- Calcium signaling and nucleotide metabolism
- Connexins and lens biology
- Neonatal Respiratory Health Research
- Immune Response and Inflammation
- Receptor Mechanisms and Signaling
- Protein Kinase Regulation and GTPase Signaling
- Neutrophil, Myeloperoxidase and Oxidative Mechanisms
- Ion Transport and Channel Regulation
- Pancreatic function and diabetes
- Neuropeptides and Animal Physiology
- Mitochondrial Function and Pathology
- Phagocytosis and Immune Regulation
- Erythrocyte Function and Pathophysiology
- Cell death mechanisms and regulation
- Cardiomyopathy and Myosin Studies
- Parathyroid Disorders and Treatments
- Extracellular vesicles in disease
Case Western Reserve University
2015-2024
University School
2013-2024
University Hospitals of Cleveland
1987-2022
National Institutes of Health
2002-2018
Clinical Orthopaedics and Related Research
2018
Institute of Molecular Biology and Biophysics
2005-2015
Case Comprehensive Cancer Center
1987-2014
Milbank Memorial Fund
2010-2012
University of Bamberg
2006
National Institute of Diabetes and Digestive and Kidney Diseases
2000-2002
BCL-2 is a 26-kDa integral membrane protein that represses apoptosis by an unknown mechanism. Recent findings indicate Ca2+ release from the endoplasmic reticulum (ER) mediates in mouse lymphoma cells. In view of growing evidence localizes to ER, as well mitochondria and perinuclear membrane, we investigated possibility regulating fluxes through ER membrane. A cDNA encoding was introduced into WEHI7.2 cells two subclones, W.Hb12 W.Hb13, which express high low levels mRNA protein,...
A recently described peptide hormone, endothelin, is a potent vasoconstrictor, but it unclear whether endothelin has other biological actions. These experiments extend the range of actions to stimulation mitogenesis. Endothelin at low concentrations (0.1-10 nM) induced mitogenesis by quiescent rat glomerular mesangial cells in culture. Mitogenesis was accompanied activation phospholipase C with increased inositol phosphate turnover and increments intracellular [Ca2+]. also activated Na+/H+...
Abstract Several mechanistically distinct models of nonclassical secretion, including exocytosis secretory lysosomes, shedding plasma membrane microvesicles, and direct efflux through transporters, have been proposed to explain the rapid export caspase-1-processed IL-1β from monocytes/macrophages in response activation P2X7 receptors (P2X7R) by extracellular ATP. We compared contribution these mechanisms P2X7R-stimulated secretion primary bone marrow-derived macrophages isolated wild-type,...
Necrosulfonamide inhibits pyroptosis through direct inhibition of gasdermin D.
Abstract Although extracellular ATP is abundant at sites of inflammation, its role in activating inflammasome signalling neutrophils not well characterized. In the current study, we demonstrate that human and murine express functional cell-surface P2X 7 R, which leads to ATP-induced loss intracellular K + , NLRP3 activation IL-1β secretion. R caused a sustained increase [Ca 2+ ], indicative channel opening. there are multiple polymorphic variants found from donors but with differential...
Interleukin-1β (IL-1β) is a pro-inflammatory cytokine that plays an important role in host defense and inflammatory diseases. The maturation secretion of IL-1β are mediated by caspase-1, protease processes pro-IL-1β into biologically active IL-1β. activity caspase-1 controlled the inflammasome, multiprotein complex formed NLR proteins adaptor ASC, induces activation caspase-1. current model proposes changes intracellular concentration K<sup>+</sup> potentiate induced recognition bacterial...
Gasdermin-D (GSDMD) in inflammasome-activated macrophages is cleaved by caspase-1 to generate N-GSDMD fragments. then oligomerizes the plasma membrane (PM) form pores that increase permeability, leading pyroptosis and IL-1β release. In contrast, we report although required for secretion NLRP3-activated human murine neutrophils, does not localize PM or permeability pyroptosis. Instead, biochemical microscopy studies reveal neutrophils predominantly associates with azurophilic granules LC3+...
Apoptotic cell death is important for embryonic development, immune homeostasis, and pathogen elimination. Innate cells also undergo a very rapid form of termed pyroptosis after activating the protease caspase-1. The hemichannel pannexin-1 has been implicated in both processes. In this study, we describe characterization pannexin-1-deficient mice. LPS-primed bone marrow-derived macrophages lacking activated caspase-1 secreted its substrates IL-1β IL-18 normally stimulation with ATP,...
Abstract Perturbation of intracellular ion homeostasis is a major cellular stress signal for activation NLRP3 inflammasome signaling that results in caspase-1–mediated production IL-1β and pyroptosis. However, the relative contributions decreased cytosolic K+ concentration versus increased Ca2+ ([Ca2+]) remain disputed incompletely defined. We investigated roles elevated [Ca2+] downstream responses primary murine dendritic cells macrophages response to two canonical agonists (ATP nigericin)...
Abstract Although neutrophils are the most abundant cells in acute infection and inflammation, relatively little attention has been paid to their role inflammasome formation IL-1β processing. In present study, we investigated mechanism by which process response Streptococcus pneumoniae. Using a murine model of S. pneumoniae corneal infection, demonstrated requirement for bacterial clearance, showed that Nod-like receptor protein 3 (NLRP3), apoptosis-associated speck-like containing caspase...
Neutrophil Extracellular Traps (NETs), a web-like structure of cytosolic and granule proteins assembled on decondensed chromatin, kill pathogens causes tissue damage in diseases. Whether NETs can cancer cells is unexplored. Here, we report that combination glutaminase inhibitor CB-839 5-FU inhibits the growth PIK3CA mutant colorectal cancers (CRCs) xenograft, syngeneic, genetically engineered mouse models part through NETs. Disruption by either DNase I treatment or depletion neutrophils CRCs...
The mechanisms underlying caspase-1 activation and IL-1beta processing during inflammatory of monocytes macrophages are not well defined. Here, we describe an in vitro proteolytic assay that allows for comparison regulatory components a cell-free system separately from the confounding issue secretion. Analysis lysates unstimulated Bac1 murine indicated slow rate basal maturation IL-1beta. In contrast, brief (5 min) treatment intact with extracellular ATP (as activator P2X(7) receptor) or...
We have developed a method for measuring the local concentration of ATP at extracellular surface live cells. This relies on specific attachment to cell chimeric protein that consists IgG-binding domain Staphylococcus aureus A fused in-frame with complete sequence firefly luciferase (proA-luc). Expression proA-luc in Escherichia coli and its one-step affinity purification are straightforward. Attachment cells is demonstrated be antibody dependent using several suspended adherent types. Light...
1-[<i>N</i>,<i>O</i>-Bis(5-isoquinolinesulfonyl)-<i>N</i>-methyl-l-tyrosyl]-4-phenylpiperazine (KN-62) and<i>N</i>-[1-[<i>N</i>-methyl-<i>p</i>-(5 isoquinolinesulfonyl)benzyl]-2-(4 phenylpiperazine)ethyl]-5-isoquinolinesulfonamide (KN-04) potently inhibit the human lymphocyte P2Z receptor, an ATP-gated cation channel [<i>Br J Pharmacol </i><b>120</b>:1483–1490 (1997)]. Although molecular identity of receptor has not been established, it shares many functional characteristics with cloned...
Extracellular ATP and other nucleotides function as autocrine paracrine signaling factors in many tissues. Recent studies suggest that P2 nucleotide receptors ecto-nucleotidases compete for a limited pool of endogenously released within cell surface microenvironments are functionally segregated from the bulk extracellular compartment. To test this hypothesis, we have used luciferase-based methods to continuously record levels monolayers human 1321N1 astrocytoma cells under resting...
Hyperammonemia and sarcopenia (loss of skeletal muscle) are consistent abnormalities in cirrhosis portosystemic shunting. We have shown that muscle ubiquitin-proteasome components not increased with hyperammonemia despite sarcopenia. This suggests an alternative mechanism proteolysis contributes to cirrhosis. hypothesized autophagy could be this pathway since we observed increases classic markers, LC3 lipidation, beclin-1 expression, p62 degradation immunoblots protein cirrhotic patients....
Abstract The proinflammatory cytokines IL-1β and IL-18 are inactive until cleaved by the enzyme caspase-1. Stimulation of P2X7 receptor (P2X7R), an ATP-gated ion channel, triggers rapid activation In this study we demonstrate that pretreatment primary Bac1 murine macrophages with TLR agonists is required for caspase-1 P2X7R but it not itself. Caspase-1 nigericin, a K+/H+ ionophore, similarly requires LPS priming. This priming dependent on protein synthesis, given cyclohexamide blocks ability...