Activation of Gq signaling by Pasteurella multocida toxin inhibits the osteoblastogenic-like actions of Activin A in C2C12 myoblasts, a cell model of fibrodysplasia ossificans progressiva

Bone ◽  
2019 ◽  
Vol 127 ◽  
pp. 592-601 ◽  
Author(s):  
Julia K. Ebner ◽  
Gabriele M. König ◽  
Evi Kostenis ◽  
Peter Siegert ◽  
Klaus Aktories ◽  
...  
Bone ◽  
2018 ◽  
Vol 109 ◽  
pp. 168-177 ◽  
Author(s):  
Teun J. de Vries ◽  
Ton Schoenmaker ◽  
Dimitra Micha ◽  
Jolanda Hogervorst ◽  
Siham Bouskla ◽  
...  

2018 ◽  
Vol 27 (04) ◽  
pp. 215-221
Author(s):  
R. Morhart ◽  
O. Semler ◽  
L. Seefried

ZusammenfassungBei der Fibrodysplasia ossificans progressiva (FOP) besteht aufgrund einer aktivierenden Mutation im Gen für den Activin A Rezeptor Typ 1 (ACVR1 / ALK2), eine Prädisposition zu heterotoper Knochenbildung in Weichgeweben, insbesondere der Muskulatur. Die Prävalenz der Erkrankung wird in einer Größenordnung von 1 pro 1–2 Mio. angegeben. Klinisch kommt es intrauterin zu Fehlbildungen, z. B. zu einem bds. Hallux valgus, der bei der überwiegenden Mehrheit der Patienten bereits bei Geburt besteht. Postnatal kommt es meist in den ersten Lebensjahren beginnend im Schulter-/ Nackenbereich episodenartig bereits nach kleineren Verletzungen zu schmerzhaften Weichteilreaktionen, sogenannten flareups die nachfolgend im Sinne einer enchondralen Ossifikation verknöchern. Die Akkumulation dieser irreversiblen Verknöcherungen im Weichgewebe bedingt eine zunehmende Einschränkung der Beweglichkeit bis hin zur kompletten Einsteifung des Körpers. Letztlich kommt es durch die fortschreitende Rigidität des Thorax zu einer respiratorischen Insuffizienz und kardialer Dekompensation.Therapeutisch steht im Vordergrund die Vermeidung von Traumata als Auslöser für die Entstehung extraossären Knochengewebes, insbesondere auch der Verzicht auf unnötige iatrogene Schädigungen durch Operationen, Biopsien und intramuskuläre Injektionen. Supportiv sind eine adäquate Hilfsmittelversorgung, psychologische Unterstützung und eine analgetische Versorgung erforderlich. Im Falle eines Traumas werden kurzfristig hochdosiert Glucocorticoide empfohlen, um das Risiko und Ausmaß der flare-ups und nachfolgender Verknöcherungen zu reduzieren. Ergänzend können NSAR hilfreich sein. Derzeit werden unterschiedliche neue Therapieansätze entwickelt. Am weitesten fortgeschritten ist dabei der Retinolsäure Rezeptor Gamma (RARg) Agonist Palovarotene, der durch Interferenz mit der ALK2 vermittelten Signalkaskade einen zentralen Punkt im Pathomechanismus der Erkrankung adressiert.


2019 ◽  
Author(s):  
Lily Huang ◽  
Chris Schoenherr ◽  
Lili Wang ◽  
Xialing Wen ◽  
Joyce McClain ◽  
...  

Author(s):  
Kevin de Vries ◽  
Anna Nikishova ◽  
Benjamin Czaja ◽  
Gábor Závodszky ◽  
Alfons G. Hoekstra

2012 ◽  
Vol 51 (05) ◽  
pp. 179-185 ◽  
Author(s):  
M. Wendisch ◽  
D. Aurich ◽  
R. Runge ◽  
R. Freudenberg ◽  
J. Kotzerke ◽  
...  

SummaryTechnetium radiopharmaceuticals are well established in nuclear medicine. Besides its well-known gamma radiation, 99mTc emits an average of five Auger and internal conversion electrons per decay. The biological toxicity of these low-energy, high-LET (linear energy transfer) emissions is a controversial subject. One aim of this study was to estimate in a cell model how much 99mTc can be present in exposed cells and which radiobiological effects could be estimated in 99mTc-overloaded cells. Methods: Sodium iodine symporter (NIS)- positive thyroid cells were used. 99mTc-uptake studies were performed after preincubation with a non-radioactive (cold) stannous pyro - phosphate kit solution or as a standard 99mTc pyrophosphate kit preparation or with pure pertechnetate solution. Survival curves were analyzed from colony-forming assays. Results: Preincubation with stannous complexes causes irreversible intracellular radioactivity retention of 99mTc and is followed by further pertechnetate influx to an unexpectedly high 99mTc level. The uptake of 99mTc pertechnetate in NIS-positive cells can be modified using stannous pyrophosphate from 3–5% to >80%. The maximum possible cellular uptake of 99mTc was 90 Bq/cell. Compared with nearly pure extracellular irradiation from routine 99mTc complexes, cell survival was reduced by 3–4 orders of magnitude after preincubation with stannous pyrophosphate. Conclusions: Intra cellular 99mTc retention is related to reduced survival, which is most likely mediated by the emission of low-energy electrons. Our findings show that the described experiments constitute a simple and useful in vitro model for radiobiological investigations in a cell model.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Xu Gao ◽  
Jingya Dai ◽  
Guifang Li ◽  
Xinya Dai

Abstract Objective In this work, we investigated the effects of gambogic acid (GA) on lipopolysaccharide (LPS)-induced apoptosis and inflammation in a cell model of neonatal pneumonia. Method Human WI-38 cells were maintained in vitro and incubated with various concentrations of GA to examine WI-38 survival. GA-preincubated WI-38 cells were then treated with LPS to investigate the protective effects of GA on LPS-induced death, apoptosis and inflammation. Western blot assay was utilized to analyze the effect of GA on tropomyosin receptor kinase A (TrkA) signaling pathway in LPS-treated WI-38 cells. In addition, human AKT serine/threonine kinase 1 (Akt) gene was knocked down in WI-38 cells to further investigate the associated genetic mechanisms of GA in protecting LPS-induced inflammation and apoptosis. Results Pre-incubating WI-38 cells with low and medium concentrations GA protected LPS-induced cell death, apoptosis and inflammatory protein productions of IL-6 and MCP-1. Using western blot assay, it was demonstrated that GA promoted TrkA phosphorylation and Akt activation in LPS-treated WI-38 cells. Knocking down Akt gene in WI-38 cells showed that GA-associated protections against LPS-induced apoptosis and inflammation were significantly reduced. Conclusions GA protected LPS-induced apoptosis and inflammation, possibly through the activations of TrkA and Akt signaling pathway. This work may broaden our understanding on the molecular mechanisms of human neonatal pneumonia.


2021 ◽  
Vol 11 (15) ◽  
pp. 7060
Author(s):  
Antonia Mancuso ◽  
Maria Chiara Cristiano ◽  
Massimo Fresta ◽  
Daniele Torella ◽  
Donatella Paolino

Ethosomes® are one of the main deformable vesicles proposed to overcome the stratum corneum. They are composed of lecithin, ethanol and water, resulting in round vesicles characterized by a narrow size distribution and a negative surface charge. Taking into account their efficiency to deliver drugs into deeper skin layers, the current study was designed to evaluate the influence of different lipids on the physico-chemical features of traditional ethosomes in the attempt to influence their fate. Three lipids (DOPE, DSPE and DOTAP) were used for the study, but only DOTAP conferred a net positive charge to ethosomes, maintaining a narrow mean size lower than 300 nm and a good polydispersity index. Stability and in vitro cytotoxic studies have been performed using Turbiscan Lab analysis and MTT dye exclusion assay, respectively. Data recorded demonstrated the good stability of modified ethosomes and a reasonable absence of cell mortality when applied to human keratinocytes, NCTC 2544, which are used as a cell model. Finally, the best formulations were selected to evaluate their ability to encapsulate drugs, through the use of model compounds. Cationic ethosomes encapsulated oil red o and rhodamine b in amounts comparable to those recorded from conventional ethosomes (over 50%). Results recorded from this study are encouraging as cationic ethosomes may open new opportunities for skin delivery.


Sign in / Sign up

Export Citation Format

Share Document