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1.
Front Neurol ; 13: 866243, 2022.
Article in English | MEDLINE | ID: mdl-35707038

ABSTRACT

Spinal Muscular Atrophy (SMA) is characterized by muscle atrophy and weakness and has an incidence of 1:11. 000 live births which projects an estimated population in the UK of 650-1,300 affected patients. Standards of Care (SoC) were updated in 2017 and they have been widely adopted as a reference for implementation of care in SMA across the globe. The effectiveness of implementation and adherence to these standards across different countries is unclear. The aim of this study is to describe the experience of individuals with SMA regarding their care in the UK. An online anonymised survey was sent out via patient organizations, the UK SMA Patient Registry, professional networks, and social media to reach across the UK. The survey captured demographic profile, professionals involved in a patient's care, Interventions and access to mobility aids and home adaptations. Participants responded about their access to services and to rate how important each professional and intervention was for their health and wellbeing. One hundred and twenty-eight responses were collected with a median age of 34 years (1-81). Seventy-three percent of participants were adults and 60% men. Overall good access to neurologist (>90%) but limited to nurse specialist (48%) and physiotherapist (57%). Good access to respiratory support was reported but limited for interventions for positioning and bracing and exercise. This survey highlights that access to certain professionals for people with SMA is limited in the UK. Striking differences were noted between pediatric and adult populations. Limited access to care were regularly reported, with half of the study population consistently not accessing full multidisciplinary care. Access to interventions for contracture management were recorded to have significant limitations. Mobility aids and home adaptations are widely available and were also reported as the most valued interventions. Access to nutritional support or speech and language therapy appears only to be available for a small proportion of the participants. Access to respiratory care was good especially in severe forms of SMA. We found pockets of good practice in the UK that align with the SoC. However, access is not equal for adults and children and access to certain professionals is significantly limited.

2.
J Clin Med ; 10(23)2021 Nov 25.
Article in English | MEDLINE | ID: mdl-34884219

ABSTRACT

Our primary aim was to establish the prevalence of pain within limb girdle muscular dystrophy R9 (LGMDR9). As part of the Global FKRP Registry, patients are asked to complete the Short Form McGill Pain Questionnaire (SF-MPQ) annually. We used the results of this questionnaire to determine individuals' maximum pain score and total pain score and examined overall pain intensity and associations between pain intensity and LGMDR9 genotypes, age, and ambulatory status. We also considered the pain descriptors used and pain progression over time. Of the 502 patients, 87% reported current pain and 25% reported severe current pain. We found no associations in pain severity between the different genotypes of LGMDR9. However, we did find statistically significant associations between pain severity and ambulatory status and between our paediatric and adult populations. We found pain descriptors to be more common words that one may associate with non-neural pain, and we found that a significant number of individuals (69%) reported a fluctuating pain pattern over time. We concluded that pain should be considered a significant issue among individuals with LGMDR9 requiring management. Implications regarding assessment of pain for other degenerative diseases are discussed.

3.
Phys Rev Lett ; 127(10): 108002, 2021 Sep 03.
Article in English | MEDLINE | ID: mdl-34533328

ABSTRACT

Thin elastic films can spontaneously attach to liquid interfaces, offering a platform for tailoring their physical, chemical, and optical properties. Current understanding of the elastocapillarity of thin films is based primarily on studies of planar sheets. We show that curved shells can be used to manipulate interfaces in qualitatively different ways. We elucidate a regime where an ultrathin shell with vanishing bending rigidity imposes its own rest shape on a liquid surface, using experiment and theory. Conceptually, the pressure across the interface "inflates" the shell into its original shape. The setup is amenable to optical applications as the shell is transparent, free of wrinkles, and may be manufactured over a range of curvatures.

4.
Dis Model Mech ; 14(7)2021 07 01.
Article in English | MEDLINE | ID: mdl-34296752

ABSTRACT

Exercise may ameliorate the eventual heart failure inherent in human aging. In this study, we use zebrafish to understand how aging and exercise affect cardiomyocyte turnover and myocardial remodelling. We show that cardiomyocyte proliferation remains constant throughout life but that onset of fibrosis is associated with a late increase in apoptosis. These findings correlate with decreases in voluntary swimming activity, critical swimming speed (Ucrit), and increases in biomarkers of cardiac insufficiency. The ability to respond to severe physiological stress is also impaired with age. Although young adult fish respond with robust cardiomyocyte proliferation in response to enforced swimming, this is dramatically impaired in older fish and served by a smaller proliferation-competent cardiomyocyte population. Finally, we show that these aging responses can be improved through increased activity throughout adulthood. However, despite improvement in Ucrit and the proliferative response to stress, the size of the proliferating cardiomyocyte population remained unchanged. The zebrafish heart models human aging and reveals the important trade-off between preserving cardiovascular fitness through exercise at the expense of accelerated fibrotic change.


Subject(s)
Myocytes, Cardiac , Zebrafish , Aging/physiology , Animals , Apoptosis , Cell Proliferation , Heart/physiology , Myocytes, Cardiac/metabolism , Zebrafish/metabolism
5.
Ann Clin Transl Neurol ; 7(5): 757-766, 2020 05.
Article in English | MEDLINE | ID: mdl-32342672

ABSTRACT

OBJECTIVE: The Global FKRP Registry is a database for individuals with conditions caused by mutations in the Fukutin-Related Protein (FKRP) gene: limb girdle muscular dystrophy R9 (LGMDR9, formerly LGMD2I) and congenital muscular dystrophies MDC1C, Muscle-Eye-Brain Disease and Walker-Warburg Syndrome. The registry seeks to further understand the natural history and prevalence of FKRP-related conditions; aid the rapid identification of eligible patients for clinical studies; and provide a source of information to clinical and academic communities. METHODS: Registration is patient-initiated through a secure online portal. Data, reported by both patients and their clinicians, include: age of onset, presenting symptoms, family history, motor function and muscle strength, respiratory and cardiac function, medication, quality of life and pain. RESULTS: Of 663 registered participants, 305 were genetically confirmed LGMDR9 patients from 23 countries. A majority of LGMDR9 patients carried the common mutation c.826C > A on one or both alleles; 67.9% were homozygous and 28.5% were compound heterozygous for this mutation. The mean ages of symptom onset and disease diagnosis were higher in individuals homozygous for c.826C > A compared with individuals heterozygous for c.826C > A. This divergence was replicated in ages of loss of running ability, wheelchair-dependence and ventilation assistance; consistent with the milder phenotype associated with individuals homozygous for c.826C > A. In LGMDR9 patients, 75.1% were currently ambulant and 24.6%, nonambulant (unreported in 0.3%). Cardiac impairment was reported in 23.2% (30/129). INTERPRETATION: The Global FKRP Registry enables the collection of patient natural history data, which informs academics, healthcare professionals and industry. It represents a trial-ready cohort of individuals and is centrally placed to facilitate recruitment to clinical studies.


Subject(s)
Muscular Dystrophies, Limb-Girdle/genetics , Pentosyltransferases/genetics , Registries , Walker-Warburg Syndrome/genetics , Adolescent , Adult , Age of Onset , Aged , Child , Cohort Studies , Female , Humans , Male , Middle Aged , Muscular Dystrophies, Limb-Girdle/physiopathology , Phenotype , Walker-Warburg Syndrome/physiopathology , Young Adult
6.
Radiol Case Rep ; 14(5): 634-638, 2019 May.
Article in English | MEDLINE | ID: mdl-30923590

ABSTRACT

Obese patients constitute 40% of the adult population. MRIs of obese patients are typically challenging because of the effects of a large field of view on image quality and the increased risk of thermal burns from contact with the bore. In this case report, the impacts of obesity on MRI procedures and safety are introduced. Then a case is presented of a 30-year old female cervical cancer patient who received an MRI simulation to verify the placement of a titanium tandem and colpostats for brachytherapy. A large magnetic susceptibility artifact was detected near the right pelvis during the MRI scout indicating the presence of ferrous material. The source of the artifact turned out to be a disposable lighter that was stored inside the patient's pannus. The finding highlights an unanticipated risk to MRI safety and image quality associated with large body habitus.

7.
Elife ; 72018 06 29.
Article in English | MEDLINE | ID: mdl-29956664

ABSTRACT

Abnormalities of the arterial valve leaflets, predominantly bicuspid aortic valve, are the commonest congenital malformations. Although many studies have investigated the development of the arterial valves, it has been assumed that, as with the atrioventricular valves, endocardial to mesenchymal transition (EndMT) is the predominant mechanism. We show that arterial is distinctly different from atrioventricular valve formation. Whilst the four septal valve leaflets are dominated by NCC and EndMT-derived cells, the intercalated leaflets differentiate directly from Tnnt2-Cre+/Isl1+ progenitors in the outflow wall, via a Notch-Jag dependent mechanism. Further, when this novel group of progenitors are disrupted, development of the intercalated leaflets is disrupted, resulting in leaflet dysplasia and bicuspid valves without raphe, most commonly affecting the aortic valve. This study thus overturns the dogma that heart valves are formed principally by EndMT, identifies a new source of valve interstitial cells, and provides a novel mechanism for causation of bicuspid aortic valves without raphe.


Subject(s)
Aortic Valve/abnormalities , Epithelial Cells/pathology , Heart Valve Diseases/pathology , Jagged-1 Protein/genetics , Myocytes, Smooth Muscle/pathology , Receptor, Notch1/genetics , Stem Cells/pathology , Animals , Aortic Valve/metabolism , Aortic Valve/pathology , Bicuspid Aortic Valve Disease , Biomarkers/metabolism , Cell Differentiation , Cell Lineage/genetics , Cell Tracking/methods , Embryo, Mammalian , Epithelial Cells/metabolism , Gene Expression , Heart Valve Diseases/genetics , Heart Valve Diseases/metabolism , Humans , Integrases/genetics , Integrases/metabolism , Jagged-1 Protein/metabolism , LIM-Homeodomain Proteins/genetics , LIM-Homeodomain Proteins/metabolism , Mice , Mice, Transgenic , Myocytes, Smooth Muscle/metabolism , Receptor, Notch1/metabolism , Stem Cells/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Troponin T/genetics , Troponin T/metabolism
8.
J Anat ; 232(4): 554-567, 2018 04.
Article in English | MEDLINE | ID: mdl-29034473

ABSTRACT

The arterial roots are important transitional regions of the heart, connecting the intrapericardial components of the aortic and pulmonary trunks with their ventricular outlets. They house the arterial (semilunar) valves and, in the case of the aorta, are the points of coronary arterial attachment. Moreover, because of the semilunar attachments of the valve leaflets, the arterial roots span the anatomic ventriculo-arterial junction. By virtue of this arrangement, the interleaflet triangles, despite being fibrous, are found on the ventricular aspect of the root and located within the left ventricular cavity. Malformations and diseases of the aortic root are common and serious. Despite the mouse being the animal model of choice for studying cardiac development, few studies have examined the structure of their arterial roots. As a consequence, our understanding of their formation and maturation is incomplete. We set out to clarify the anatomical and histological features of the mouse arterial roots, particularly focusing on their walls and the points of attachment of the valve leaflets. We then sought to determine the embryonic lineage relationships between these tissues, as a forerunner to understanding how they form and mature over time. Using histological stains and immunohistochemistry, we show that the walls of the mouse arterial roots show a gradual transition, with smooth muscle cells (SMC) forming the bulk of wall at the most distal points of attachments of the valve leaflets, while being entirely fibrous at their base. Although the interleaflet triangles lie within the ventricular chambers, we show that they are histologically indistinguishable from the arterial sinus walls until the end of gestation. Differences become apparent after birth, and are only completed by postnatal day 21. Using Cre-lox-based lineage tracing technology to label progenitor populations, we show that the SMC and fibrous tissue within the walls of the mature arterial roots share a common origin from the second heart field (SHF) and exclude trans-differentiation of myocardium as a source for the interleaflet triangle fibrous tissues. Moreover, we show that the attachment points of the leaflets to the walls, like the leaflets themselves, are derived from the outflow cushions, having contributions from both SHF-derived endothelial cells and neural crest cells. Our data thus show that the arterial roots in the mouse heart are similar to the features described in the human heart. They provide a framework for understanding complex lesions and diseases affecting the aortic root.


Subject(s)
Aortic Valve/abnormalities , Aortic Valve/growth & development , Heart Defects, Congenital/embryology , Heart/growth & development , Pulmonary Valve/abnormalities , Pulmonary Valve/growth & development , Animals , Aortic Valve Stenosis/etiology , Aortic Valve Stenosis/pathology , Fluorescent Antibody Technique , Hypoplastic Left Heart Syndrome/etiology , Hypoplastic Left Heart Syndrome/pathology , Mice , Mice, Mutant Strains , Myocytes, Smooth Muscle/physiology , Neural Crest/growth & development
9.
J Hepatol ; 63(6): 1421-8, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26264933

ABSTRACT

BACKGROUND & AIMS: Ubiquitination is a reversible protein modification involved in the major cellular processes that define cell phenotype and behaviour. Ubiquitin modifications are removed by a large family of proteases named deubiquitinases. The role of deubiquitinases in hepatic stellate cell (HSC) activation and their contribution to fibrogenesis are poorly defined. We have identified that the deubiquitinase ubiquitin C-terminal hydrolase 1 (UCHL1) is highly induced following HSC activation, determined its function in activated HSC and its potential as a therapeutic target for fibrosis. METHODS: Deubiquitinase expression was determined in day 0 and day 10 HSC. Increased UCHL1 expression was confirmed in human HSC and in an alcoholic liver disease (ALD) patient liver. The importance of UCHL1 in hepatic fibrosis was investigated in CCl4 and bile duct ligation injured mice using a pharmacological inhibitor (LDN 57444). The effects of UCHL1 inhibition on HSC proliferation were confirmed by Western blot and 3H thymidine incorporation. RESULTS: Here we report that pharmacological inhibition of UCHL1 blocks progression of established fibrosis in CCl4 injured mice. UCHL1 siRNA knockdown, LDN 57444 treatment, or HSC isolated from UCHL1(-/-) mice show attenuated proliferation in response to the mitogen, platelet-derived growth factor. Additionally, we observed changes in the phosphorylation of the cell cycle regulator retinoblastoma protein (Rb) in the absence of UCHL1 highlighting a potential mechanism for the reduced proliferative response. CONCLUSIONS: UCHL1 expression is highly upregulated upon HSC activation and is involved in the regulation of HSC proliferation. This study highlights therapeutic opportunities for pharmacological targeting of UCHL1 in chronic liver disease.


Subject(s)
Liver Diseases/enzymology , Ubiquitin Thiolesterase/metabolism , Animals , Biomarkers/metabolism , Carbon Tetrachloride/toxicity , Cell Proliferation , Cell Transdifferentiation , Cells, Cultured , Chronic Disease , Gene Knockdown Techniques , Hepatic Stellate Cells/enzymology , Hepatic Stellate Cells/pathology , Humans , Liver Cirrhosis, Experimental/enzymology , Liver Cirrhosis, Experimental/pathology , Liver Diseases/pathology , Liver Diseases/therapy , Liver Diseases, Alcoholic/enzymology , Liver Diseases, Alcoholic/pathology , Mice , Mice, Knockout , Myofibroblasts/enzymology , Myofibroblasts/pathology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Ubiquitin Thiolesterase/antagonists & inhibitors , Ubiquitin Thiolesterase/deficiency , Ubiquitin Thiolesterase/genetics , Ubiquitin-Specific Proteases/genetics , Ubiquitin-Specific Proteases/metabolism , Ubiquitination
10.
J Hepatol ; 60(4): 782-91, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24333183

ABSTRACT

BACKGROUND & AIMS: Neutrophils are important immune effectors required for sterile and non-sterile inflammatory responses. However, neutrophils are associated with pathology in drug-induced liver injury, acute alcoholic liver disease, and ischemia-reperfusion injury. An understanding of the complex mechanisms that control neutrophil recruitment to the injured liver is desirable for developing strategies aimed at limiting neutrophil-mediated cellular damage. METHODS: Wt, tlr2(-/-), tlr4(-/-), and s100a9(-/-) mice were administered CCl4 either acutely (8, 24, 48, or 72 h) or chronically (8 weeks) and livers investigated by histological (IHC for neutrophils, fibrogenesis, proliferation, and chemotactic proteins) or molecular approaches (qRT-PCR for neutrophil chemoattractant chemokines and cytokines as well as pro-fibrogenic genes). RESULTS: Mice lacking TLR2 or S100A9 failed to recruit neutrophils to the injured liver and had a defective hepatic induction of the neutrophil chemokine CXCL-2. Hierarchy between TLR2 and S100A9 proved to be complex. While induction of S100A9 was dependent on TLR2 in isolated neutrophils, there was a more complicated two-way signalling cross-talk between TLR2 and S100A9 in whole liver. However, wound-healing and regenerative responses of the liver were unaffected in these genetic backgrounds as well as in wild type mice, in which neutrophils were depleted by infusion of Ly-6G antibody. CONCLUSIONS: We have identified TLR2 and S100A8/S100A9 as key regulators of hepatic CXCL-2 expression and neutrophil recruitment. This novel TLR2-S100A9-CXCL-2 pathway may be of use in development of new strategies for selectively manipulating neutrophils in liver disease without impairing normal wound healing and regenerative responses.


Subject(s)
Calgranulin B/immunology , Chemical and Drug Induced Liver Injury, Chronic/immunology , Chemical and Drug Induced Liver Injury/immunology , Chemokine CXCL2/immunology , Neutrophil Infiltration/immunology , Toll-Like Receptor 2/immunology , Animals , Calgranulin A/immunology , Calgranulin B/genetics , Carbon Tetrachloride/toxicity , Chemical and Drug Induced Liver Injury/pathology , Chemical and Drug Induced Liver Injury, Chronic/pathology , Chemokine CXCL2/biosynthesis , Disease Models, Animal , Humans , Leukocyte L1 Antigen Complex/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Signal Transduction/immunology , Toll-Like Receptor 2/deficiency , Toll-Like Receptor 2/genetics , Toll-Like Receptor 4/deficiency , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/immunology , Wound Healing/immunology
11.
PLoS One ; 8(4): e61804, 2013.
Article in English | MEDLINE | ID: mdl-23626731

ABSTRACT

Within the animal kingdom, human cooperation represents an outlier. As such, there has been great interest across a number of fields in identifying the factors that support the complex and flexible variety of cooperation that is uniquely human. The ability to identify and preferentially interact with better social partners (partner choice) is proposed to be a major factor in maintaining costly cooperation between individuals. Here we show that the ability to engage in flexible and effective partner choice behavior can be traced back to early childhood. Specifically, across two studies, we demonstrate that by 3 years of age, children identify effective communication as "helpful" (Experiments 1 & 2), reward good communicators with information (Experiment 1), and selectively reciprocate communication with diverse cooperative acts (Experiment 2). Taken together, these results suggest that even in early childhood, humans take advantage of cooperative benefits, while mitigating free-rider risks, through appropriate partner choice behavior.


Subject(s)
Communication , Cooperative Behavior , Intention , Interpersonal Relations , Child, Preschool , Female , Helping Behavior , Humans , Male , Reward
12.
Hepatology ; 57(2): 817-28, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22996371

ABSTRACT

UNLABELLED: Phosphorylation of the RelA subunit at serine 536 (RelA-P-Ser536) is important for hepatic myofibroblast survival and is mechanistically implicated in liver fibrosis. Here, we show that a cell-permeable competing peptide (P6) functions as a specific targeted inhibitor of RelA-P-Ser536 in vivo and exerts an antifibrogenic effect in two progressive liver disease models, but does not impair hepatic inflammation or innate immune responses after lipopolysaccharide challenge. Using kinase assays and western blotting, we confirm that P6 is a substrate for the inhibitory kappa B kinases (IKKs), IKKα and IKKß, and, in human hepatic myofibroblasts, P6 prevents RelA-P-Ser536, but does not affect IKK activation of IκBα. We demonstrate that RelA-P-Ser536 is a feature of human lung and skin fibroblasts, but not lung epithelial cells, in vitro and is present in sclerotic skin and diseased lungs of patients suffering from idiopathic pulmonary fibrosis. CONCLUSION: RelA-P-Ser536 may be a core fibrogenic regulator of fibroblast phenotype.


Subject(s)
Immunity, Innate/drug effects , Liver Cirrhosis/prevention & control , Peptide Fragments/pharmacology , Transcription Factor RelA/antagonists & inhibitors , Adult , Animals , Carbon Tetrachloride Poisoning/drug therapy , Fibroblasts/metabolism , Humans , I-kappa B Kinase/physiology , Lipopolysaccharides/pharmacology , Male , Mice , Peptide Fragments/metabolism , Phosphorylation , Serine , Transcription Factor RelA/metabolism , Transcription Factor RelA/pharmacology
13.
Hepatology ; 57(3): 1238-49, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23080298

ABSTRACT

UNLABELLED: Toll-like receptors (TLRs) function as key regulators of liver fibrosis and are able to modulate the fibrogenic actions of nonparenchymal liver cells. The fibrogenic signaling events downstream of TLRs on Kupffer cells (KCs) and hepatic stellate cells (HSCs) are poorly defined. Here, we describe the MAP3K tumor progression locus 2 (Tpl2) as being important for the activation of extracellular regulated kinase (ERK) signaling in KCs and HSCs responding to stimulation of TLR4 and TLR9. KCs lacking Tpl2 display defects with TLR induction of cytokines interleukin (IL)-1ß, IL-10, and IL-23. tpl2(-/-) HSCs were unable to increase expression of fibrogenic genes IL-1ß and tissue inhibitor of metalloproteinase 1 (TIMP-1), with the latter being the result of defective stimulation of TIMP-1 promoter activity by TLRs. To determine the in vivo relevance of Tpl2 signaling in liver fibrosis, we compared the fibrogenic responses of wild-type (WT) and tpl2(-/-) mice in three distinct models of chronic liver injury. In the carbon tetrachloride and methionine-choline-deficient diet models, we observed a significant reduction in fibrosis in mice lacking Tpl2, compared to WT controls. However, in the bile duct ligation model, there was no effect of tpl2 deletion, which may reflect a lesser role for HSCs in wounding response to biliary injury. CONCLUSION: We conclude that Tpl2 is an important signal transducer for TLR activation of gene expression in KCs and HSCs by the ERK pathway and that suppression of its catalytic activity may be a route toward suppressing fibrosis caused by hepatocellular injuries. (HEPATOLOGY 2013).


Subject(s)
Hepatic Stellate Cells/physiology , Liver Cirrhosis/metabolism , MAP Kinase Kinase Kinases/metabolism , MAP Kinase Signaling System/physiology , Proto-Oncogene Proteins/metabolism , Tissue Inhibitor of Metalloproteinase-1/genetics , Animals , Cells, Cultured , Cytokines/metabolism , Hepatic Stellate Cells/cytology , Hepatocytes/cytology , Hepatocytes/physiology , Kupffer Cells/cytology , Kupffer Cells/physiology , Liver Cirrhosis/genetics , Liver Cirrhosis/pathology , MAP Kinase Kinase Kinases/genetics , Macrophages/cytology , Macrophages/physiology , Male , Mice , Mice, Knockout , Proto-Oncogene Proteins/genetics , Tissue Inhibitor of Metalloproteinase-1/metabolism , Toll-Like Receptor 4/metabolism , Toll-Like Receptor 9/metabolism , Transcription, Genetic/physiology
14.
Am J Pathol ; 180(3): 929-939, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22210479

ABSTRACT

Cardiac remodeling and hypertrophy are the pathological consequences of cardiovascular disease and are correlated with its associated mortality. Activity of the transcription factor NF-κB is increased in the diseased heart; however, our present understanding of how the individual subunits contribute to cardiovascular disease is limited. We assign a new role for the c-Rel subunit as a stimulator of cardiac hypertrophy and fibrosis. We discovered that c-Rel-deficient mice have smaller hearts at birth, as well as during adulthood, and are protected from developing cardiac hypertrophy and fibrosis after chronic angiotensin infusion. Results of both gene expression and cross-linked chromatin immunoprecipitation assay analyses identified transcriptional activators of hypertrophy, myocyte enhancer family, Gata4, and Tbx proteins as Rel gene targets. We suggest that the p50 subunit could limit the prohypertrophic actions of c-Rel in the normal heart, because p50 overexpression in H9c2 cells repressed c-Rel levels and the absence of cardiac p50 was associated with increases in both c-Rel levels and cardiac hypertrophy. We report for the first time that c-Rel is highly expressed and confined to the nuclei of diseased adult human hearts but is restricted to the cytoplasm of normal cardiac tissues. We conclude that c-Rel-dependent signaling is critical for both cardiac remodeling and hypertrophy. Targeting its activities could offer a novel therapeutic strategy to limit the effects of cardiac disease.


Subject(s)
Cardiomegaly/etiology , Myocardium/pathology , NF-kappa B/physiology , Proto-Oncogene Proteins c-rel/physiology , Angiotensins/pharmacology , Animals , Blood Pressure/physiology , Cardiomegaly/metabolism , Cardiomegaly/pathology , Fibrosis , Gene Deletion , Gene Expression Regulation , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , NF-kappa B p50 Subunit/metabolism , NF-kappa B p50 Subunit/physiology , Proto-Oncogene Proteins c-rel/deficiency , Proto-Oncogene Proteins c-rel/genetics , Signal Transduction/physiology , Ventricular Remodeling/physiology
15.
Nat Med ; 17(12): 1668-73, 2011 Nov 27.
Article in English | MEDLINE | ID: mdl-22120177

ABSTRACT

Tissue homeostasis requires an effective, limited wound-healing response to injury. In chronic disease, failure to regenerate parenchymal tissue leads to the replacement of lost cellular mass with a fibrotic matrix. The mechanisms that dictate the balance of cell regeneration and fibrogenesis are not well understood. Here we report that fibrogenic hepatic stellate cells (HSCs) in the liver are negative regulators of hepatocyte regeneration. This negative regulatory function requires stimulation of the 5-hydroxytryptamine 2B receptor (5-HT(2B)) on HSCs by serotonin, which activates expression of transforming growth factor ß1 (TGF-ß1), a powerful suppressor of hepatocyte proliferation, through signaling by mitogen-activated protein kinase 1 (ERK) and the transcription factor JunD. Selective antagonism of 5-HT(2B) enhanced hepatocyte growth in models of acute and chronic liver injury. We also observed similar effects in mice lacking 5-HT(2B) or JunD or upon selective depletion of HSCs in wild-type mice. Antagonism of 5-HT(2B) attenuated fibrogenesis and improved liver function in disease models in which fibrosis was pre-established and progressive. Pharmacological targeting of 5-HT(2B) is clinically safe in humans and may be therapeutic in chronic liver disease.


Subject(s)
Liver Cirrhosis/therapy , Receptor, Serotonin, 5-HT2B/metabolism , Wound Healing , Animals , Cell Proliferation/drug effects , Cells, Cultured , Chronic Disease , Electrophoresis, Polyacrylamide Gel , Hepatic Stellate Cells/drug effects , Hepatic Stellate Cells/metabolism , Hepatocytes/cytology , Hepatocytes/drug effects , Immunohistochemistry , Indoles/pharmacology , Liver Cirrhosis/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Mitogen-Activated Protein Kinase 1/genetics , Mitogen-Activated Protein Kinase 1/metabolism , Proto-Oncogene Proteins c-jun/genetics , Proto-Oncogene Proteins c-jun/metabolism , Rats , Rats, Sprague-Dawley , Receptor, Serotonin, 5-HT2B/drug effects , Serotonin/pharmacology , Serotonin 5-HT2 Receptor Antagonists/pharmacology , Signal Transduction , Transforming Growth Factor beta1/genetics , Transforming Growth Factor beta1/metabolism , Urea/analogs & derivatives , Urea/pharmacology
16.
Clin Cancer Res ; 10(21): 7427-37, 2004 Nov 01.
Article in English | MEDLINE | ID: mdl-15534120

ABSTRACT

PURPOSE: The purpose of this study was to determine the role of functional interactions between pancreatic cancer cells and pancreatic stellate cells (PSCs) in the formation of the desmoplastic reaction (DR) in pancreatic cancer and to characterize the effect of type I collagen (the predominant component of the DR) on pancreatic cancer cell phenotype. EXPERIMENTAL DESIGN: PSCs and type I collagen were identified in sections of pancreatic cancer using immunohistochemistry, and their anatomic relationship was studied. Interactions among pancreatic cancer cell lines (MIA PaCa-2, Panc-1, and AsPC-1), primary cultures of human PSCs, and type I collagen were investigated in a series of tissue culture models. RESULTS: In vivo, the DR causes gross distortion of normal pancreas, bringing cancer cells into close contact with numerous PSCs and abundant type I collagen. In tissue culture models of pancreatic cancer, conditioned media from each cell line increased PSC [3H]thymidine incorporation up to 6.3-fold that of controls, and AsPC-1 cells also increased PSC collagen synthesis 1.3-fold. Type I collagen was observed to increase long-term survival of pancreatic cancer cells treated with 5-fluorouracil, by up to 62% in clonogenic assays. This was because type I collagen increased the proliferation of cancer cells ([3H]thymidine incorporation was up to 2.8-fold that of cells cultured on tissue culture plastic) and reduced apoptosis of AsPC-1 cells in response to 5-fluorouracil (by regulating mcl-1). CONCLUSIONS: These experiments elucidate a mechanism by which the DR in pancreatic cancer may form and, via the collagen within it, promote the malignant phenotype of pancreatic cancer cells, suggesting significant detriment to the host.


Subject(s)
Adenocarcinoma/pathology , Carcinoma, Pancreatic Ductal/pathology , Collagen Type I/physiology , Pancreatic Neoplasms/pathology , Adenocarcinoma/metabolism , Apoptosis , Blotting, Western , Carcinoma, Pancreatic Ductal/metabolism , Cell Line, Tumor , Cell Proliferation , Cell Separation , Collagen/chemistry , Collagen/metabolism , Collagen Type I/metabolism , Culture Media, Conditioned/pharmacology , DNA/metabolism , Dose-Response Relationship, Drug , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Humans , Immunohistochemistry , Pancreas/cytology , Pancreatic Neoplasms/metabolism , Phenotype , RNA/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Tissue Inhibitor of Metalloproteinase-1/metabolism
17.
Virology ; 307(1): 143-53, 2003 Mar 01.
Article in English | MEDLINE | ID: mdl-12667822

ABSTRACT

Bacterially expressed nucleocapsid (N) protein, from respiratory syncytial virus (RSV), was used to investigate RNA binding in a modified North-Western blotting protocol. The recombinant protein demonstrated no sequence specificity in binding RNA representing either the antigenomic leader sequence or the nonspecific sequence derived from a plasmid vector. When recombinant N was purified on CsCl gradients, two types of structure, both with densities indicating that they contained RNA, could be visualised by negative-stain electron microscopy. Structures similar to nucleocapsids (NC) from RSV-infected cells were observed, as were ring structures. A small fragment of the N (amino acids 1-92) was all that was required for the production of NC-like structures. Another mutant with an internal deletion could form rings but not NC-like structures. This suggests that this domain (amino acids 121-160) may be important for maintaining helical stability. Further analysis has also identified a potential site in the amino-terminus that may be involved in an interaction with the phosphoprotein. A domain model of the RSV N protein is presented which, similar to that of other paramyxoviruses, supports the idea that the amino-terminus is important for NC assembly.


Subject(s)
Nucleocapsid Proteins/metabolism , Phosphoproteins/metabolism , Respiratory Syncytial Viruses/genetics , Animals , Binding Sites , Cell Line , Nucleocapsid Proteins/chemistry , RNA, Viral/genetics , RNA, Viral/isolation & purification , Recombinant Proteins/metabolism , Respiratory Syncytial Viruses/metabolism , Transcription, Genetic
18.
J Gen Virol ; 83(Pt 8): 1831-1839, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12124447

ABSTRACT

Nucleocapsid (N) proteins from representative viruses of three genera within the Paramyxoviridae were expressed in insect cells using recombinant baculoviruses. RNA-containing structures, which appear morphologically identical to viral nucleocapsids, were isolated and subsequently imaged under a transmission electron microscope. Analysis of these images revealed marked differences in nucleocapsid morphology among the genera investigated, most notably between viruses of the Paramyxovirinae and the Pneumovirinae subfamilies. Helical pitch measurements were made, revealing that measles virus (MV, a Morbillivirus within the subfamily Paramyxovirinae) N protein produces helices that adopt multiple conformations with varying degrees of flexibility, while that of the Rubulavirus simian virus type 5 (SV5, subfamily Paramyxovirinae) produces more rigid structures with a less heterogeneous pitch distribution. Nucleocapsids produced by respiratory syncytial virus (RSV, subfamily Pneumovirinae) appear significantly narrower than those of MV and SV5 and have a longer pitch than the most extended form of MV. In addition to helical nucleocapsids, ring structures were also produced, image analysis of which has demonstrated that rings assembled from MV N protein consist of 13 subunits. This is consistent with previous reports that Sendai virus nucleocapsids have 13.07 subunits per turn. It was determined, however, that SV5 subnucleocapsid rings have 14 subunits, while rings derived from the radically different RSV nucleocapsid have been found to contain predominantly 10 subunits.


Subject(s)
Nucleocapsid Proteins/ultrastructure , Nucleocapsid/metabolism , Nucleocapsid/ultrastructure , Paramyxoviridae/classification , Paramyxoviridae/ultrastructure , Animals , Baculoviridae/genetics , Baculoviridae/metabolism , Cell Line , Humans , Microscopy, Electron , Nucleocapsid/genetics , Nucleocapsid Proteins/chemistry , Nucleocapsid Proteins/isolation & purification , Nucleocapsid Proteins/metabolism , Paramyxoviridae/chemistry , Paramyxoviridae/genetics , Protein Conformation , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Recombinant Proteins/ultrastructure , Spodoptera
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