Ex vivo measurement of tissue distribution of a nitroxide radical after intravenous injection and its in vivo imaging using a rapid scan ESR-CT system

AbstractRespiratory mucociliary clearance (MCC) is a key defense mechanism that functions to entrap and transport inhaled pollutants, particulates, and pathogens away from the lungs. Previous work has identified a number of anesthetics to have cilia depressive effects in vitro. Wild-type C57BL/6 J mice received intra-tracheal installation of 99mTc-Sulfur colloid, and were imaged using a dual-modality SPECT/CT system at 0 and 6 h to measure baseline MCC (n = 8). Mice were challenged for one hour with inhalational 1.5% isoflurane, or intraperitoneal ketamine (100 mg/kg)/xylazine (20 mg/kg), ketamine (0.5 mg/kg)/dexmedetomidine (50 mg/kg), fentanyl (0.2 mg/kg)/1.5% isoflurane, propofol (120 mg/Kg), or fentanyl/midazolam/dexmedetomidine (0.025 mg/kg/2.5 mg/kg/0.25 mg/kg) prior to MCC assessment. The baseline MCC was 6.4%, and was significantly reduced to 3.7% (p = 0.04) and 3.0% (p = 0.01) by ketamine/xylazine and ketamine/dexmedetomidine challenge respectively. Importantly, combinations of drugs containing fentanyl, and propofol in isolation did not significantly depress MCC. Although no change in cilia length or percent ciliation was expected, we tried to correlate ex-vivo tracheal cilia ciliary beat frequency and cilia-generated flow velocities with MCC and found no correlation. Our results indicate that anesthetics containing ketamine (ketamine/xylazine and ketamine/dexmedetomidine) significantly depress MCC, while combinations containing fentanyl (fentanyl/isoflurane, fentanyl/midazolam/dexmedetomidine) and propofol do not. Our method for assessing MCC is reproducible and has utility for studying the effects of other drug combinations.

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GFP-Aequorin Protein Sensor for Ex Vivo and In Vivo Imaging of Ca 2+ Dynamics in High-Ca 2+ Organelles

Cell Chemical Biology ◽

10.1016/j.chembiol.2016.05.010 ◽

2016 ◽

Vol 23 (6) ◽

pp. 738-745 ◽

Cited By ~ 22

Author(s):

Paloma Navas-Navarro ◽

Jonathan Rojo-Ruiz ◽

Macarena Rodriguez-Prados ◽

María Dolores Ganfornina ◽

Loren L. Looger ◽

...

Keyword(s):

In Vivo Imaging ◽

Ex Vivo ◽

Protein Sensor

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Ex Vivo and In Vivo Imaging and Biodistribution of Aptamers Targeting the Human Matrix MetalloProtease-9 in Melanomas

PLoS ONE ◽

10.1371/journal.pone.0149387 ◽

2016 ◽

Vol 11 (2) ◽

pp. e0149387 ◽

Cited By ~ 26

Author(s):

David Kryza ◽

Frédéric Debordeaux ◽

Laurent Azéma ◽

Aref Hassan ◽

Olivier Paurelle ◽

...

Keyword(s):

In Vivo Imaging ◽

Ex Vivo ◽

Matrix Metalloprotease

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In Vivo Imaging of Peripheral Benzodiazepine Receptors in Mouse Lungs: A Biomarker of Inflammation

Molecular Imaging ◽

10.2310/7290.2005.05133 ◽

2005 ◽

Vol 4 (4) ◽

pp. 7290.2005.05133 ◽

Cited By ~ 19

Author(s):

Matthew J. Hardwick ◽

Ming-Kai Chen ◽

Kwamena Baidoo ◽

Martin G. Pomper ◽

Tomás R. Guilarte

Keyword(s):

In Vivo Imaging ◽

Ex Vivo ◽

Inflammatory Diseases ◽

Imaging Techniques ◽

Benzodiazepine Receptors ◽

Small Animal ◽

Small Animal Pet ◽

Planar Imaging ◽

Peripheral Benzodiazepine Receptors

The ability to visualize the immune response with radioligands targeted to immune cells will enhance our understanding of cellular responses in inflammatory diseases. Peripheral benzodiazepine receptors (PBR) are present in monocytes and neutrophils as well as in lung tissue. We used lipopolysaccharide (LPS) as a model of inflammation to assess whether the PBR could be used as a noninvasive marker of inflammation in the lungs. Planar imaging of mice administrated 10 or 30 mg/kg LPS showed increased [123I]-( R)-PK11195 radioactivity in the thorax 2 days after LPS treatment relative to control. Following imaging, lungs from control and LPS-treated mice were harvested for ex vivo gamma counting and showed significantly increased radioactivity above control levels. The specificity of the PBR response was determined using a blocking dose of nonradioactive PK11195 given 30 min prior to radiotracer injection. Static planar images of the thorax of nonradioactive PK11195 pretreated animals showed a significantly lower level of radiotracer accumulation in control and in LPS-treated animals ( p < .05). These data show that LPS induces specific increases in PBR ligand binding in the lungs. We also used in vivo small-animal PET studies to demonstrate increased [11C]-( R)-PK11195 accumulation in the lungs of LPS-treated mice. This study suggests that measuring PBR expression using in vivo imaging techniques may be a useful biomarker to image lung inflammation.

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Convergent molecular, cellular, and cortical neuroimaging signatures of major depressive disorder

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2008004117 ◽

2020 ◽

Vol 117 (40) ◽

pp. 25138-25149

Author(s):

Kevin M. Anderson ◽

Meghan A. Collins ◽

Ru Kong ◽

Kacey Fang ◽

Jingwei Li ◽

...

Keyword(s):

Major Depressive Disorder ◽

Negative Affect ◽

Depressive Disorder ◽

Single Cell ◽

In Vivo Imaging ◽

Ex Vivo ◽

Integrated Analysis ◽

Down Regulation ◽

Major Depressive

Major depressive disorder emerges from the complex interactions of biological systems that span genes and molecules through cells, networks, and behavior. Establishing how neurobiological processes coalesce to contribute to depression requires a multiscale approach, encompassing measures of brain structure and function as well as genetic and cell-specific transcriptional data. Here, we examine anatomical (cortical thickness) and functional (functional variability, global brain connectivity) correlates of depression and negative affect across three population-imaging datasets: UK Biobank, Brain Genomics Superstruct Project, and Enhancing NeuroImaging through Meta Analysis (ENIGMA; combined n ≥ 23,723). Integrative analyses incorporate measures of cortical gene expression, postmortem patient transcriptional data, depression genome-wide association study (GWAS), and single-cell gene transcription. Neuroimaging correlates of depression and negative affect were consistent across three independent datasets. Linking ex vivo gene down-regulation with in vivo neuroimaging, we find that transcriptional correlates of depression imaging phenotypes track gene down-regulation in postmortem cortical samples of patients with depression. Integrated analysis of single-cell and Allen Human Brain Atlas expression data reveal somatostatin interneurons and astrocytes to be consistent cell associates of depression, through both in vivo imaging and ex vivo cortical gene dysregulation. Providing converging evidence for these observations, GWAS-derived polygenic risk for depression was enriched for genes expressed in interneurons, but not glia. Underscoring the translational potential of multiscale approaches, the transcriptional correlates of depression-linked brain function and structure were enriched for disorder-relevant molecular pathways. These findings bridge levels to connect specific genes, cell classes, and biological pathways to in vivo imaging correlates of depression.

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Synthesis, Ex Vivo Evaluation, and Radiolabeling of Potent 1,5-Diphenylpyrrolidin-2-one Cannabinoid Subtype-1 Receptor Ligands as Candidates for In Vivo Imaging

Journal of Medicinal Chemistry ◽

10.1021/jm800416m ◽

2008 ◽

Vol 51 (18) ◽

pp. 5833-5842 ◽

Cited By ~ 55

Author(s):

Sean R. Donohue ◽

Joseph H. Krushinski ◽

Victor W. Pike ◽

Eyassu Chernet ◽

Lee Phebus ◽

...

Keyword(s):

In Vivo Imaging ◽

Ex Vivo ◽

Receptor Ligands

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Supramolecular Encapsulation of Small-Ultra Red Fluorescent Proteins in Virus-Like Nanoparticles for Non-Invasive In Vivo Imaging Agents

10.26434/chemrxiv.12067851.v1 ◽

2020 ◽

Author(s):

Fabian C. Herbert ◽

Olivia Brohlin ◽

Tyler Galbraith ◽

Candace Benjamin ◽

Cesar A. Reyes ◽

...

Keyword(s):

In Vivo Imaging ◽

Fluorescent Protein ◽

Fluorescent Proteins ◽

Ex Vivo ◽

Imaging Agents ◽

Non Invasive ◽

Red Fluorescent Proteins ◽

Ex Vivo Imaging

<div> <div> <div> <p>Icosahedral virus-like particles (VLPs) derived from bacteriophages Qβ and PP7 encapsulating small-ultra red fluorescent protein (smURFP) were produced using a versatile supramolecualr capsid dissassemble-reassemble approach. The generated fluorescent VLPs display identical structural properties to their non-fluorescent analogs. Encapsulated smURFP shows indistinguishable photochemical properties to its unencapsulated counterpart, exhibits outstanding stability towards pH, and produces bright in vitro images following phagocytosis by macrophages. In vivo imaging allows biodistribution to be imaged at different time points. Ex vivo imaging of intravenously administered encapsulated smURFP reveleas localization in the liver and </p> </div> </div> <div> <div> <p>kidneys after 2 h blood circulation and substantial elimination constructs as non-invasive in vivo imaging agents. </p> </div> </div> </div>

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Preclinical Pharmacokinetics, Tissue Distribution, and Primary Safety Evaluation of Indo5, a Novel Selective Inhibitor of c-Met and Trks

Frontiers in Pharmacology ◽

10.3389/fphar.2021.711126 ◽

2021 ◽

Vol 12 ◽

Author(s):

Teng Luo ◽

Fei-Xiang Zhang ◽

Ke Zhao ◽

Hui-Ying Gao ◽

Shou-Guo Zhang ◽

...

Keyword(s):

Tissue Distribution ◽

Intravenous Injection ◽

Safety Evaluation ◽

Rat Plasma ◽

Selective Inhibitor ◽

Preclinical Pharmacokinetics ◽

Normal Number ◽

Liquid Chromatography Tandem Mass ◽

Tissue Homogenates

The compound [3-(1H-benzimidazol-2-methylene)-5-(2-methylphenylaminosulfo)-2-indolone], known as Indo5, is a novel selective inhibitor of c-Met and Trks, and it is a promising anticancer candidate against hepatocellular carcinoma (HCC). Assessing the pharmacokinetic properties, tissue distribution, and toxicity of Indo5 is critical for its medicinal evaluation. A series of sensitive and specific liquid chromatography-tandem mass spectrometry methods were developed and validated to determine the concentration of Indo5 in rat plasma and tissue homogenates. These methods were then applied to investigate the pharmacokinetics and tissue distribution of Indo5 in rats. After intravenous injection of Indo5, the maximum concentration (Cmax) and the time at which Cmax was reached (Tmax) were 1,565.3 ± 286.2 ng/ml and 1 min, respectively. After oral administration, Cmax and Tmax were 54.7 ± 10.4 ng/ml and 2.0 ± 0.48 h, respectively. We calculated the absolute oral bioavailability of Indo5 in rats to be 1.59%. Following intravenous injection, the concentrations of Indo5 in various tissues showed the following order: liver > kidney ≈ heart > lung ≈ large intestine ≈ small intestine ≈ stomach > spleen > brain ≈ testes; hence, Indo5 distributed highest in the liver and could not cross the blood–brain or blood–testes barriers. Continuous injection of Indo5 for 21 days did not lead to liver injury, considering unchanged ALT and AST levels, normal histological architecture of the liver, and normal number and frequencies of immune cells in the liver, indicating a very low toxicity of Indo5 in vivo. Collectively, our findings provide a comprehensive understanding of the biological actions of Indo5 in vivo and further support its development as an antitumor treatment for HCC patients.

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Synthesis of 68Ga-Labeled cNGR-Based Glycopeptides and In Vivo Evaluation by PET Imaging

Pharmaceutics ◽

10.3390/pharmaceutics13122103 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2103

Author(s):

Barbara Gyuricza ◽

Judit P. Szabó ◽

Viktória Arató ◽

Noémi Dénes ◽

Ágnes Szűcs ◽

...

Keyword(s):

Tissue Distribution ◽

Pet Imaging ◽

Ex Vivo ◽

Distribution Data ◽

Melanoma Tumor ◽

In Vivo Evaluation ◽

Imaging Results ◽

Ngr Peptide ◽

Ex Vivo Tissue

Tumor hypoxia induces angiogenesis, which is required for tumor cell survival. The aminopeptidase N receptor (APN/CD13) is an excellent marker of angiogenesis since it is overexpressed in angiogenic blood vessels and in tumor cells. Asparagine-glycine-arginine (NGR) peptide analogs bind selectively to the APN/CD13 recepto, therefore, they are important vector molecules in the development of a PET radiotracer which is capable of detecting APN-rich tumors. To investigate the effect of glycosylation and pegylation on in-vivo efficacy of an NGR-based radiotracer, two 68Ga-labeled radioglycopeptides were synthesized. A lactosamine derivative was applied to glycosylation of the NGR derivative and PEG4 moiety was used for pegylation. The receptor targeting potential and biodistribution of the radiopeptides were evaluated with in vivo PET imaging studies and ex vivo tissue distribution studies using B16-F10 melanoma tumor-bearing mice. According to these studies, all synthesized radiopeptides were capable of detecting APN expression in B16-F10 melanoma tumor. In addition, lower hepatic uptake, higher tumor-to background (T/M) ratio and prolonged circulation time were observed for the novel [68Ga]-10 radiotracer due to pegylation and glycosylation, resulting in more contrasting PET imaging. These in vivo PET imaging results correlated well with the ex vivo tissue distribution data.

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