scholarly journals Development of an in vivo Model to Investigate the Role of the Heavy Metal Efflux System Sil from cupriavidus Metallidurans Ch34 in Resistance to Silver and Copper Ions

2010 ◽  
Vol 98 (3) ◽  
pp. 504a
Author(s):  
Elisabeth Ngonlong Ekendé ◽  
Max Mergeay ◽  
Jean-Marie Ruysschaert ◽  
Guy Vandenbussche
Keyword(s):  
Heavy Metal ◽  
Copper Ions ◽  
In Vivo Model ◽  
Efflux System ◽  
Cupriavidus Metallidurans Ch34 ◽  
Cupriavidus Metallidurans ◽  
Metal Efflux ◽  
Heavy Metal Efflux

scholarly journals A Yes-Associated Protein (YAP) and Insulin-Like Growth Factor 1 Receptor (IGF-1R) Signaling Loop Is Involved in Sorafenib Resistance in Hepatocellular Carcinoma

Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3812
Author(s):  
Mai-Huong T. Ngo ◽  
Sue-Wei Peng ◽  
Yung-Che Kuo ◽  
Chun-Yen Lin ◽  
Ming-Heng Wu ◽  
...  
Keyword(s):  
Nuclear Translocation ◽  
Combination Index ◽  
Specific Inhibitor ◽  
In Vivo Model ◽  
Mrna Levels ◽  
Margin Distribution ◽  
Related Proteins ◽  
Emt Markers

The role of a YAP-IGF-1R signaling loop in HCC resistance to sorafenib remains unknown. Method: Sorafenib-resistant cells were generated by treating naïve cells (HepG2215 and Hep3B) with sorafenib. Different cancer cell lines from databases were analyzed through the ONCOMINE web server. BIOSTORM–LIHC patient tissues (46 nonresponders and 21 responders to sorafenib) were used to compare YAP mRNA levels. The HepG2215_R-derived xenograft in SCID mice was used as an in vivo model. HCC tissues from a patient with sorafenib failure were used to examine differences in YAP and IGF-R signaling. Results: Positive associations exist among the levels of YAP, IGF-1R, and EMT markers in HCC tissues and the levels of these proteins increased with sorafenib failure, with a trend of tumor-margin distribution in vivo. Blocking YAP downregulated IGF-1R signaling-related proteins, while IGF-1/2 treatment enhanced the nuclear translocation of YAP in HCC cells through PI3K-mTOR regulation. The combination of YAP-specific inhibitor verteporfin (VP) and sorafenib effectively decreased cell viability in a synergistic manner, evidenced by the combination index (CI). Conclusion: A YAP-IGF-1R signaling loop may play a role in HCC sorafenib resistance and could provide novel potential targets for combination therapy with sorafenib to overcome drug resistance in HCC.

The Role of Mannose Receptor in IgE Production in an in vivo Model of Cat Allergy

2011 ◽  
Vol 127 (2) ◽  
pp. AB152-AB152
Author(s):  
A.M. Ghaemmaghami ◽  
M. Emara ◽  
L. Martinez-Pomares ◽  
F. Shakib
Keyword(s):  
Mannose Receptor ◽  
In Vivo Model ◽  
Cat Allergy

scholarly journals Phenotypic assays in yeast and zebrafish reveal drugs that rescue ATP13A2 deficiency

2019 ◽  
Vol 1 (1) ◽  
Author(s):  
Ursula Heins-Marroquin ◽  
Paul P Jung ◽  
Maria Lorena Cordero-Maldonado ◽  
Alexander D Crawford ◽  
Carole L Linster
Keyword(s):  
Heavy Metal ◽  
High Throughput ◽  
High Throughput Screening ◽  
Drug Testing ◽  
Neuronal Ceroid Lipofuscinosis ◽  
Drug Repurposing ◽  
In Vivo Model ◽  
Inherited Disorders ◽  
Zebrafish Model

Abstract Mutations in ATP13A2 (PARK9) are causally linked to the rare neurodegenerative disorders Kufor-Rakeb syndrome, hereditary spastic paraplegia and neuronal ceroid lipofuscinosis. This suggests that ATP13A2, a lysosomal cation-transporting ATPase, plays a crucial role in neuronal cells. The heterogeneity of the clinical spectrum of ATP13A2-associated disorders is not yet well understood and currently, these diseases remain without effective treatment. Interestingly, ATP13A2 is widely conserved among eukaryotes, and the yeast model for ATP13A2 deficiency was the first to indicate a role in heavy metal homeostasis, which was later confirmed in human cells. In this study, we show that the deletion of YPK9 (the yeast orthologue of ATP13A2) in Saccharomyces cerevisiae leads to growth impairment in the presence of Zn2+, Mn2+, Co2+ and Ni2+, with the strongest phenotype being observed in the presence of zinc. Using the ypk9Δ mutant, we developed a high-throughput growth rescue screen based on the Zn2+ sensitivity phenotype. Screening of two libraries of Food and Drug Administration-approved drugs identified 11 compounds that rescued growth. Subsequently, we generated a zebrafish model for ATP13A2 deficiency and found that both partial and complete loss of atp13a2 function led to increased sensitivity to Mn2+. Based on this phenotype, we confirmed two of the drugs found in the yeast screen to also exert a rescue effect in zebrafish—N-acetylcysteine, a potent antioxidant, and furaltadone, a nitrofuran antibiotic. This study further supports that combining the high-throughput screening capacity of yeast with rapid in vivo drug testing in zebrafish can represent an efficient drug repurposing strategy in the context of rare inherited disorders involving conserved genes. This work also deepens the understanding of the role of ATP13A2 in heavy metal detoxification and provides a new in vivo model for investigating ATP13A2 deficiency.

Concurrent opposite effects of trichostatin A, an inhibitor of histone deacetylases, on expression of α-MHC and cardiac tubulins: implication for gain in cardiac muscle contractility

2005 ◽  
Vol 288 (3) ◽  
pp. H1477-H1490 ◽  
Author(s):  
Francesca J. Davis ◽  
Jyothish B Pillai ◽  
Madhu Gupta ◽  
Mahesh P. Gupta
Keyword(s):  
Cardiac Myocytes ◽  
Histone Deacetylases ◽  
Contractile Function ◽  
Trichostatin A ◽  
In Vivo Model ◽  
Ang Ii ◽  
Cardiac Contractile Function ◽  
Noticeable Effect

Histone deacetylases (HDACs) are a family of enzymes that catalyze the removal of acetyl groups from core histones, resulting in change of chromatin structure and gene transcription activity. In the heart, HDACs are targets of hypertrophic signaling, and their nonspecific inhibition by trichostatin A (TSA) attenuates hypertrophy of cultured cardiac myocytes. In this study, we examined the effect of TSA on two major determinants of cardiac contractility: α-myosin heavy chain (MHC) expression and microtubular composition and organization. TSA upregulated the expression of α-MHC in cultured cardiac myocytes, as well as in an in vivo model of hypothyroid rats. Studies designed to delineate mechanisms of α-MHC induction by TSA revealed an obligatory role of early growth response factor-1 on activation of the α-MHC promoter. Concurrently, TSA downregulated the expression of α- and β-tubulins and prevented the induction of tubulins by a hypertrophy agonist, ANG II. The ANG II-mediated increased proportion of α- and β-tubulins associated with polymerized microtubules was also markedly reduced after treatment of cells by TSA. Results obtained from immunofluorescent microscopy indicated that TSA had no noticeable effect on the organization of cardiac microtubules in control cells, whereas it prevented the ANG II-induced dense parallel linear arrays of microtubules to a profile similar to that of controls. Together, these results demonstrate that inhibition of HDACs by TSA regulates the cardiac α-MHC and tubulins in a manner predictive of improved cardiac contractile function. These studies improve our understanding of the role of HDACs on cardiac hypertrophy with implications in development of new therapeutic agents for treatment of cardiac abnormalities.

Platelet-Derived Microparticles Induce Angiogenesis and Stimulate Post-Ischemic Revascularization.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3916-3916
Author(s):  
Olga Dashevsky ◽  
Alexander Brill ◽  
Julia Rivo ◽  
David Varon
Keyword(s):  
Endothelial Cells ◽  
Aortic Ring ◽  
In Vivo Model ◽  
Preliminary Evaluation ◽  
Vegf Receptor ◽  
In Vivo Models ◽  
Ischemic Region

Abstract Platelet attachment to the subcellular matrix at injured sites of the vasculature is followed by their activation and release of microparticles. Platelet-derived microparticles (PMP) have been shown to be involved in the regulation of hemostasis. However, little is known about the role of PMP in the regulation of angiogenesis and related clinical conditions. We have recently demonstrated that platelets as a cellular system induce angiogenic responses both in vitro and in vivo. In the present study, we investigated the potential role of PMP in angiogenesis. A strong dose-dependent pro-angiogenic effect of PMP in the rat aortic ring model (5.3±2.1 mm2 surface covered with sprouting vessels versus 0.24±0.2 mm2 in the control, p<0.001) was observed. This effect was reversed by selective inhibition of VEGF, bFGF and PDGF (surface covered with vessels 0.7±0.5 mm2, 1.7±1.5 mm2, and 2.4±1.2 mm2, respectively, p<0.02 versus control), but not by inhibition of heparanase (5.1±0.8 mm2, p>0.5 versus control). PMP exert their stimulatory effect via PI3-kinase, Src kinase and ERK, whereas protein kinase C seems not to be involved, as judged by the aortic ring sprouting model. Using confocal and electron microscopy, we also demonstrate that PMP bind to non-activated endothelial cells. In addition, PMP markedly increased invasion of human endothelial cells through a layer of matrigel. This effect was abolished by an inhibitor of VEGF receptor tyrosine phosphorylation or laminaran sulfate (heparanase inhibitor). It was also partially reduced by PDGF blocking mAb, whereas blocking of bFGF had no effect. Furthermore, we have demonstrated that PMP induce angiogenesis in an in vivo model, in which beads (30 μl) of 4% agarose gel containing the substances under study were transplanted subcutaneously into mice. Image analysis of the capillary area revealed the following: control beads − 0.2±0.05 mm2, VEGF + bFGF containing beads − 4.8±1.1 mm2, PMP (100 μg/ml) containing beads − 5.1±1.3 mm2, p<0.001 versus control. The latter finding was further supported by immunohistochemical staining of the skin in the vicinity of the beads for von Willebrand factor, a marker of endothelial cells (control − 4.0±3.2, VEGF+bFGF − 12±4.4, PMP − 17±6.5 capillaries per view field, p<0.05 versus control). Finally, we explored the potential effect of PMP in a rat myocardial infarction model. Ischemia was induced by LAD ligation followed by injection of either PMP or PBS into the ischemic region. Preliminary evaluation of the LAD myocardial territory in sham-operated animals revealed 157±42.0 capillaries per view field. In contrast, number of capillaries observed 3 weeks after induction of ischemia was reduced to 34±21.5. When PMP were injected into the ischemic region, there was an increase in capillary number up to 97±27.3. In conclusion, PMP induce angiogenesis in both in vitro and in vivo models. Local injection of PMP into the ischemic myocardium may improve revascularization.

IDENTIFICATION AND FUNCTIONAL ROLE OF A NOVEL INTEGRIN, ALPHA-D (alpha d), IN AN IN VIVO MODEL OF PULMONARY INFLAMMATION

1998 ◽  
Vol 26 (Supplement) ◽  
pp. 75A
Author(s):  
Thomas P. Shanley ◽  
Roscoe L. Warner ◽  
Larry Crouch ◽  
Gregory N. Dietsch ◽  
W. Michael Gallatin ◽  
...  
Keyword(s):  
Functional Role ◽  
Pulmonary Inflammation ◽  
In Vivo Model
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