scholarly journals Investigating lung responses with functional hyperpolarized xenon-129 MRI in an ex vivo rat model of asthma

2015 ◽  
Vol 76 (4) ◽  
pp. 1224-1235 ◽  
Author(s):  
David M.L. Lilburn ◽  
Amanda L. Tatler ◽  
Joseph S. Six ◽  
Clémentine Lesbats ◽  
Anthony Habgood ◽  
...  
Keyword(s):  
Rat Model ◽  
Ex Vivo ◽  
Hyperpolarized Xenon

scholarly journals AB0069 LORECIVIVINT (SM04690), AN INTRA-ARTICULAR, SMALL-MOLECULE CLK/DYRK1A INHIBITOR THAT MODULATES THE WNT PATHWAY, AS A POTENTIAL TREATMENT FOR MENISCAL INJURIES

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1335.2-1335
Author(s):  
T. Seo ◽  
V. Deshmukh ◽  
Y. Yazici
Keyword(s):  
Small Molecule ◽  
Rat Model ◽  
Wnt Pathway ◽  
Ex Vivo ◽  
Meniscal Tear ◽  
Knee Oa ◽  
Meniscus Degeneration ◽  
Anti Inflammatory ◽  
Meniscal Damage

Background:Meniscal injuries, associated with pain, stiffness, and localized swelling, are the most common pathology of the knee with a prevalence of 61 per 100,000.1Meniscal damage is a frequent finding on MRI images of knee osteoarthritis (OA)2; while a meniscal tear can lead to knee OA, knee OA can also lead to a spontaneous meniscal tear.3Efforts to repair meniscal damage have been largely unsuccessful and do not prevent the progression of degenerative changes that lead to knee OA.4The Wnt signaling pathway has been shown to be regulated during meniscal development,5,6suggesting that manipulation of this pathway may influence the regenerative capacity of the meniscus. Lorecivivint (LOR; SM04690) is an intra-articular (IA), small-molecule CLK/DYRK1A inhibitor that modulates the Wnt pathway.Objectives:LOR was evaluated in preclinical studies to determine its protective and anabolic effects in ex vivo explants and in a rat model of chemically induced inflammatory meniscus degeneration.Methods:Effects of LOR (30 nM) on expression of matrix metalloproteinases (MMPs) in cultured rat menisci treated with IL-1B were measured by qPCR. In vivo, LOR activity was evaluated in a rat model of monosodium iodoacetate (MIA) injection-induced inflammatory meniscus degeneration. A single IA injection of MIA was immediately followed by a single IA injection of LOR (0.3 ug) or vehicle. Knees were harvested on Days 1, 4, and 11 and menisci were isolated. Anti-inflammatory effects were evaluated by measuringTNFAandIL6expression by qPCR. Meniscus protection was evaluated by qPCR for MMPs and aggrecanase and anabolic effects by qPCR for collagens.Results:In ex vivo meniscal explants, LOR inhibited expression ofMMP1,MMP3, andMMP13compared to DMSO (P<0.01). In vivo, LOR significantly decreased expression of these MMPs and aggrecanase (P<0.05) compared to vehicle in the rat model of inflammatory meniscus degeneration at Day 4 after MIA injection. In addition, LOR reduced expression of inflammatory cytokinesTNFAandIL6at Day 4 compared to vehicle. Finally, LOR increased expression of collagen types I, II, and III at Day 11 after MIA injection.Conclusion:LOR exhibited protective effects in the meniscus ex vivo and in vivo by reducing the expression of catabolic enzymes compared to control. Anti-inflammatory effects of LOR were demonstrated by inhibition of inflammatory cytokine expression. Compared to vehicle, LOR increased expression of collagens in vivo, indicating potential meniscal anabolic effects. These data support further investigation of LOR as a potential disease-modifying therapy for meniscal injuries.References:[1]Logerstedt D and Snyder-Mackler L.J Orthop Sports Phys Ther. 2010[2]Englund M, et al.Rheum Dis Clin North Am. 2009[3]Englund M, et al.Radiol Clin North Am. 2009[4]von Lewinski, et al.Knee Surg Sports Traumatol Arthrosc. 2007[5]Pazin DE, et al.ORS 2012 Annual Meeting. Paper No. 0221[6]Pazin DE, et al.Dev Dyn. 2012Disclosure of Interests:Tim Seo Shareholder of: Samumed, LLC, Employee of: Samumed, LLC, Vishal Deshmukh Shareholder of: Samumed, LLC, Employee of: Samumed, LLC, Yusuf Yazici Shareholder of: Samumed, LLC, Grant/research support from: Bristol-Myers Squibb, Celgene, and Genentech, Consultant of: Celgene and Sanofi, Employee of: Samumed, LLC

Impact of triptolide during ex vivo lung perfusion on grafts after transplantation in a rat model

2021 ◽  
Vol 161 (1) ◽  
pp. e65-e74 ◽  
Author(s):  
Sarah Burki ◽  
Kentaro Noda ◽  
Brian J. Philips ◽  
Murugesan Velayutham ◽  
Sruti Shiva ◽  
...  
Keyword(s):  
Rat Model ◽  
Ex Vivo ◽  
Lung Perfusion ◽  
Ex Vivo Lung Perfusion

scholarly journals Norepinephrine Transporter Imaging in the Brain of a Rat Model of Depression Using Radioiodinated (2S, αS)-2-(α-(2-iodophenoxy)benzyl)morpholine

2012 ◽  
Vol 11 (4) ◽  
pp. 7290.2011.00049 ◽  
Author(s):  
Naoki Kanegawa ◽  
Yasushi Kiyono ◽  
Taku Sugitaa ◽  
Yuji Kuge ◽  
Yasushisa Fujibayasi ◽  
...  
Keyword(s):  
Rat Model ◽  
Thalamic Nucleus ◽  
Ex Vivo ◽  
Norepinephrine Transporter ◽  
Diagnostic Information ◽  
Brain Diseases ◽  
Imaging Biomarker ◽  
Control Group ◽  
The Brain

To visualize the norepinephrine transporters (NETs) in various brain diseases, we developed radioiodinated (2S,αS)-2-(α-(2-iodophenoxy)benzyl)morpholine ((S,S)-IPBM). This radioligand achieved the basic requirements for NET imaging. In this study, we assessed the potential of radioiodinated (S,S)-IPBM as an imaging biomarker of NET to obtain diagnostic information about depression in relation to NET expression in the brain using a rat depression model. The ex vivo autoradiographic experiments using the (S,S)-[125I]IPBM showed significantly lower accumulation of radioactivity in the locus coeruleus (LC) and the anteroventricular thalamic nucleus (AVTN) of the depression group than in those of the control group. Consequently, in vitro autoradiographic experiments showed that NET maximum binding (Bmax) values in the LC and AVTN, known as NET-rich regions, were significantly decreased in the rat model of depression when compared to those of the control rats. In addition, there was an extremely good correlation between NET Bmax and (S,S)-IPBM accumulation ( r = .98), an indication of radioiodinated IPBM as a quantitative NET imaging biomarker. The reduction in(S,S)-[125I]IPBM accumulation in the rat model of depression correlated with that of NET density. These results suggest that (S,S)-[123I]IPBM has potential as an imaging biomarker of NET to obtain diagnostic information about major depression.

Plasma expansion is key for sustained liver function and viability during normothermic and subnormothermic ex vivo machine perfusion in a rat model

2017 ◽  
Vol 66 (1) ◽  
pp. S613
Author(s):  
J.M.G. Gassner ◽  
M. Nösser ◽  
R. Horner ◽  
K.H. Hillebrandt ◽  
S. Moosburner ◽  
...  
Keyword(s):  
Liver Function ◽  
Rat Model ◽  
Ex Vivo ◽  
Machine Perfusion ◽  
Plasma Expansion

scholarly journals Tyrosine-Protein Phosphatase Non-receptor Type 9 (PTPN9) Negatively Regulates the Paracrine Vasoprotective Activity of Bone-Marrow Derived Pro-angiogenic Cells: Impact on Vascular Degeneration in Oxygen-Induced Retinopathy

2021 ◽  
Vol 9 ◽  
Author(s):  
Michel Desjarlais ◽  
Pakiza Ruknudin ◽  
Maëlle Wirth ◽  
Isabelle Lahaie ◽  
Rabah Dabouz ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Rat Model ◽  
Protein Phosphatase ◽  
Ex Vivo ◽  
Stem Cell Differentiation ◽  
Negative Regulator ◽  
Receptor Type ◽  
Vegf Receptor ◽  
Tubule Formation ◽  
Oxygen Induced Retinopathy

Background and AimInsufficient post-ischemic neovascularization is an initial key step in the pathogenesis of Oxygen-Induced Retinopathy (OIR). During neovascularization, pro-angiogenic cells (PACs) are mobilized from the bone marrow and integrate into ischemic tissues to promote angiogenesis. However, the modulation of PAC paracrine activity during OIR and the specific mechanisms involved remain to be explored. Because Tyrosine-protein phosphatase non-receptor type 9 (PTPN9) is reported to be a negative regulator of stem cell differentiation and angiogenesis signaling, we investigated its effect on PAC activity in the context of OIR.Methods and ResultsIn a rat model of OIR, higher levels of PTPN9 in the retina and in bone marrow derived PACs are associated with retinal avascular areas, lower levels of the mobilization factor SDF-1 and decreased number of CD34+/CD117+/CD133+ PACs. PACs exposed ex vivo to hyperoxia display increased PTPN9 expression, which is associated with impaired ability of PAC secretome to promote angiogenesis ex vivo (choroidal vascular sprouting) and in vitro (endothelial cell tubule formation) compared to the secretome of PACs maintained in normoxia. Suppression of PTPN9 (using siRNA) increases VEGF and SDF-1 expression to normalize PAC secretome during hyperoxia, leading to restored angiogenic ability of PAC secretome. Moreover, endothelial cells exposed to the secretome of siPTPN9-treated PACs expressed increased levels of activated form of VEGF receptor 2 (VEGFR2). In the rat model of OIR, intravitreal injection of secretome from siPTPN9-treated PACs significantly reduced retinal vaso-obliteration; this was associated with higher retinal levels of VEGF/SDF-1, and increased recruitment of PACs (CD34+ cells) to the retinal and choroidal vessels.ConclusionOur results suggest that hyperoxia alters the paracrine proangiogenic activity of BM-PACs by inducing PTPN9, which can contribute to impair post-ischemic revascularization in the context of OIR. Targeting PTPN9 restores PAC angiogenic properties, and provide a new target for vessel integrity in ischemic retinopathies.

scholarly journals Imbalance of flight-freeze responses and their cellular correlates in the Nlgn3-/y rat model of autism

2020 ◽  
Author(s):  
Natasha J Anstey ◽  
Vijayakumar Kapgal ◽  
Shashank Tiwari ◽  
Thomas C Watson ◽  
Anna KH Toft ◽  
...  
Keyword(s):  
Emotional Disorders ◽  
Rat Model ◽  
Ex Vivo ◽  
Transmembrane Protein ◽  
Autism Spectrum ◽  
Fear Learning ◽  
Flight Behaviour ◽  
Cellular Excitability ◽  
Lower Magnitude

SummaryMutations in the postsynaptic transmembrane protein neuroligin-3 are highly correlative with autism spectrum disorders (ASDs) and intellectual disabilities (IDs). Fear learning is well studied in models of these disorders, however differences in fear response behaviours are often overlooked. Whilst examining fear in a rat model of ASD/ID lacking Nlgn3, we observed that they display a greater propensity to exhibit flight responses in contrast to classic freezing seen in wildtypes during fearful situations. Consequently, we examined the physiological underpinnings of this in neurons of the periaqueductal grey (PAG), a midbrain area involved in flight-or-freeze responses. In ex vivo slices from Nlgn3-/y, rats, dorsal PAG (dPAG) neurons showed intrinsic hyperexcitability. Further analysis of this revealed lower magnitude in vivo dPAG stimulation evoked flight behaviour in Nlgn3-/y, rats, indicating the functional impact of the increased cellular excitability. This study provides new insight into potential pathophysiologies leading to emotional disorders in individuals with ASD.

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