Publications by authors named "Robert J Gropler"

176 Publications

Spatially constrained kinetic modeling with dual reference tissues improves F-flortaucipir PET in studies of Alzheimer disease.

Eur J Nucl Med Mol Imaging 2021 Feb 18. Epub 2021 Feb 18.

Mallinckrodt Institute of Radiology, Washington University School of Medicine, Campus Box 8225, 510 S. Kingshighway Blvd, St Louis, MO, 63110, USA.

Purpose: Recent studies have shown that standard compartmental models using plasma input or the cerebellum reference tissue input are generally not reliable for quantifying tau burden in dynamic F-flortaucipir PET studies of Alzheimer disease. So far, the optimal reference region for estimating F-flortaucipir delivery and specific tau binding has yet to be determined. The objective of the study is to improve F-flortaucipir brain tau PET quantification using a spatially constrained kinetic model with dual reference tissues.

Methods: Participants were classified as either cognitively normal (CN) or cognitively impaired (CI) based on clinical assessment. T1-weighted structural MRI and 105-min dynamic F-flortaucipir PET scans were acquired for each participant. Using both a simplified reference tissue model (SRTM2) and Logan plot with either cerebellum gray matter or centrum semiovale (CS) white matter as the reference tissue, we estimated distribution volume ratios (DVRs) and the relative transport rate constant R for region of interest-based (ROI) and voxelwise-based analyses. Conventional linear regression (LR) and LR with spatially constrained (LRSC) parametric imaging algorithms were then evaluated. Noise-induced bias in the parametric images was compared to estimates from ROI time activity curve-based kinetic modeling. We finally evaluated standardized uptake value ratios at early phase (SUVR, 0.7-2.9 min) and late phase (SUVR, 80-105 min) to approximate R and DVR, respectively.

Results: The percent coefficients of variation of R and DVR estimates from SRTM2 with spatially constrained modeling were comparable to those from the Logan plot and SUVRs. The SRTM2 using CS reference tissue with LRSC reduced noise-induced underestimation in the LR generated DVR images to negligible levels (< 1%). Inconsistent overestimation of DVR in the SUVR only occurred using the cerebellum reference tissue-based measurements. The CS reference tissue-based DVR and SUVR, and cerebellum-based SUVR and R provided higher Cohen's effect size d to detect increased tau deposition and reduced relative tracer transport rate in CI individuals.

Conclusion: Using a spatially constrained kinetic model with dual reference tissues significantly improved quantification of relative perfusion and tau binding. Cerebellum and CS are the suggested reference tissues to estimate R and DVR, respectively, for dynamic F-flortaucipir PET studies. Cerebellum-based SUVR and CS-based SUVR may be used to simplify F-flortaucipir PET study.
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http://dx.doi.org/10.1007/s00259-020-05134-wDOI Listing
February 2021

CC Chemokine Receptor 5 Targeted Nanoparticles Imaging the Progression and Regression of Atherosclerosis Using Positron Emission Tomography/Computed Tomography.

Mol Pharm 2021 Mar 16;18(3):1386-1396. Epub 2021 Feb 16.

Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri 63110, United States.

Chemokines and chemokine receptors play an important role in the initiation and progression of atherosclerosis by mediating the trafficking of inflammatory cells. Chemokine receptor 5 (CCR5) has major implications in promoting the development of plaques to advanced stage and related vulnerability. CCR5 antagonist has demonstrated the effective inhibition of atherosclerotic progression in mice, making it a potential biomarker for atherosclerosis management. To accurately determine CCR5 , we synthesized CCR5 targeted Comb nanoparticles through a modular design and construction strategy with control over the physiochemical properties and functionalization of CCR5 targeting peptide d-Ala-peptide T-amide (DAPTA-Comb). pharmacokinetic evaluation through Cu radiolabeling showed extended blood circulation of Cu-DAPTA-Combs conjugated with 10%, 25%, and 40% DAPTA. The different organ distribution profiles of the three nanoparticles demonstrated the effect of DAPTA on not only physicochemical properties but also targeting efficiency. positron emission tomography/computed tomography (PET/CT) imaging in an apolipoprotein E knockout mouse atherosclerosis model (ApoE) showed that the three Cu-DAPTA-Combs could sensitively and specifically detect CCR5 along the progression of atherosclerotic lesions. In an ApoE-encoding adenoviral vector (AAV) induced plaque regression ApoE mouse model, decreased monocyte recruitment, CD68+ macrophages, CCR5 expression, and plaque size were all associated with reduced PET signals, which not only further confirmed the targeting efficiency of Cu-DAPTA-Combs but also highlighted the potential of these targeted nanoparticles for atherosclerosis imaging. Moreover, the up-regulation of CCR5 and colocalization with CD68+ macrophages in the necrotic core of human plaque specimens warrant further investigation for atherosclerosis prognosis.
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http://dx.doi.org/10.1021/acs.molpharmaceut.0c01183DOI Listing
March 2021

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2021 Feb 15;14(2):e012470. Epub 2021 Feb 15.

Editor-in-Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.121.012470DOI Listing
February 2021

Heterogeneity in insulin-stimulated glucose uptake among different muscle groups in healthy lean people and people with obesity.

Diabetologia 2021 Jan 29. Epub 2021 Jan 29.

Center for Human Nutrition, Washington University School of Medicine, St Louis, MO, USA.

Aims/hypothesis: It has been proposed that muscle fibre type composition and perfusion are key determinants of insulin-stimulated muscle glucose uptake, and alterations in muscle fibre type composition and perfusion contribute to muscle, and consequently whole-body, insulin resistance in people with obesity. The goal of the study was to evaluate the relationships among muscle fibre type composition, perfusion and insulin-stimulated glucose uptake rates in healthy, lean people and people with obesity.

Methods: We measured insulin-stimulated whole-body glucose disposal and glucose uptake and perfusion rates in five major muscle groups (erector spinae, obliques, rectus abdominis, hamstrings, quadriceps) in 15 healthy lean people and 37 people with obesity by using the hyperinsulinaemic-euglycaemic clamp procedure in conjunction with [H]glucose tracer infusion (to assess whole-body glucose disposal) and positron emission tomography after injections of [O]HO (to assess muscle perfusion) and [F]fluorodeoxyglucose (to assess muscle glucose uptake). A biopsy from the vastus lateralis was obtained to assess fibre type composition.

Results: We found: (1) a twofold difference in glucose uptake rates among muscles in both the lean and obese groups (rectus abdominis: 67 [51, 78] and 32 [21, 55] μmol kg min in the lean and obese groups, respectively; erector spinae: 134 [103, 160] and 66 [24, 129] μmol kg min, respectively; median [IQR]) that was unrelated to perfusion or fibre type composition (assessed in the vastus only); (2) the impairment in insulin action in the obese compared with the lean group was not different among muscle groups; and (3) insulin-stimulated whole-body glucose disposal expressed per kg fat-free mass was linearly related with muscle glucose uptake rate (r = 0.65, p < 0.05).

Conclusions/interpretation: Obesity-associated insulin resistance is generalised across all major muscles, and is not caused by alterations in muscle fibre type composition or perfusion. In addition, insulin-stimulated whole-body glucose disposal relative to fat-free mass provides a reliable index of muscle glucose uptake rate.
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http://dx.doi.org/10.1007/s00125-021-05383-wDOI Listing
January 2021

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2021 Jan 13;14(1):e012351. Epub 2021 Jan 13.

Editor in Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.012351DOI Listing
January 2021

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 12 15;13(12):e012204. Epub 2020 Dec 15.

Editor in Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.012204DOI Listing
December 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 11 16;13(11):e012105. Epub 2020 Nov 16.

Editor-in-Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.012105DOI Listing
November 2020

Delineating the Role of Macrophages in Cardiovascular Disease: How Specific Do We Need to Be?

Circ Cardiovasc Imaging 2020 10 20;13(10):e011605. Epub 2020 Oct 20.

Division of Radiological Sciences, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.011605DOI Listing
October 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 10 20;13(10):e011986. Epub 2020 Oct 20.

Editor-in-Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.011986DOI Listing
October 2020

Galuminox: Preclinical validation of a novel PET tracer for non-invasive imaging of oxidative stress in vivo.

Redox Biol 2020 10 21;37:101690. Epub 2020 Aug 21.

Mallinckrodt Institute of Radiology, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO, 63110, USA; Department of Biomedical Engineering, School of Engineering & Applied Science, Washington University, St. Louis, 63105, USA. Electronic address:

Overproduction of reactive oxygen species (ROS) is a well-established indicator of ongoing tissue inflammation. However, there is a scarcity of molecular imaging probes capable of providing noninvasive sensitive detection of ROS for allowing longitudinal studies of disease pathology and/or monitoring therapeutic efficacy of ROS scavengers. Herein, we report synthesis and chemical characterization of a novel metalloprobe, Galuminox, a moderately fluorescent agent that detects superoxide and hydrogen peroxide generation. Using live-cell fluorescence imaging analysis, Galuminox demonstrates ability to detect superoxide and monitor effects of ROS-attenuating agents, such as Carvedilol, Dexrazoxane, and mitoTempo in lung epithelial A549 cells. Furthermore, LPS stimulation of A549 cells that either express the mitochondria targeted fluorescent protein Keima or are stained with MitoSOX, a mitochondria-specific superoxide probe, indicates preferential co-localization of Galuminox with mitochondria producing elevated amounts of superoxide. Dynamic PET/CT scans 45 min post tail-vein administration of Ga-Galuminox show 4-fold higher uptake and stable retention in lungs of LPS treated mice compared to their saline-only treated counterparts. Post preclinical PET imaging, quantitative biodistribution studies also correlate with 4-fold higher retention of the radiotracer in lungs of LPS treated mice compared with their saline-only treated control counterparts. Consistent with these observations, lung cells isolated from LPS-treated mice demonstrated elevated ROS production deploying CellROX, the ROS probe. Finally, Galuminox uptake correlates with histological and physiological evidence of acute lung injury as evident by polynuclear infiltration, thickening of the alveolar epithelial membranes and increased bronchioalveolar lavage protein content. Taken collectively, these data indicate that Ga-Galuminox tracer uptake is a measure of ROS activity in acutely injured lungs and suggests its potential utility in monitoring oxidative stress in other diseases.
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http://dx.doi.org/10.1016/j.redox.2020.101690DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7648173PMC
October 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 09 11;13(9):e011784. Epub 2020 Sep 11.

Editor in Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.011784DOI Listing
September 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 08 14;13(8):e011621. Epub 2020 Aug 14.

Editor in Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.011621DOI Listing
August 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 07 20;13(7):e011449. Epub 2020 Jul 20.

Editor in Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.011449DOI Listing
July 2020

Chemokine Receptor 2-targeted Molecular Imaging in Pulmonary Fibrosis. A Clinical Trial.

Am J Respir Crit Care Med 2021 01;203(1):78-89

Department of Radiology.

Idiopathic pulmonary fibrosis (IPF) is a progressive inflammatory lung disease without effective molecular markers of disease activity or treatment responses. Monocyte and interstitial macrophages that express the C-C motif CCR2 (chemokine receptor 2) are active in IPF and central to fibrosis. To phenotype patients with IPF for potential targeted therapy, we developed Cu-DOTA-ECL1i, a radiotracer to noninvasively track CCR2 monocytes and macrophages using positron emission tomography (PET). CCR2 cells were investigated in mice with bleomycin- or radiation-induced fibrosis and in human subjects with IPF. The CCR2 cell populations were localized relative to fibrotic regions in lung tissue and characterized using immunolocalization, single-cell mass cytometry, and RNA hybridization and then correlated with parallel quantitation of lung uptake by Cu-DOTA-ECL1i PET. Mouse models established that increased Cu-DOTA-ECL1i PET uptake in the lung correlates with CCR2 cell infiltration associated with fibrosis ( = 72). As therapeutic models, the inhibition of fibrosis by IL-1β blockade ( = 19) or antifibrotic pirfenidone ( = 18) reduced CCR2 macrophage accumulation and uptake of the radiotracer in mouse lungs. In lung tissues from patients with IPF, CCR2 cells concentrated in perifibrotic regions and correlated with radiotracer localization ( = 21). Human imaging revealed little lung uptake in healthy volunteers ( = 7), whereas subjects with IPF ( = 4) exhibited intensive signals in fibrotic zones. These findings support a role for imaging CCR2 cells within the fibrogenic niche in IPF to provide a molecular target for personalized therapy and monitoring.Clinical trial registered with www.clinicaltrials.gov (NCT03492762).
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http://dx.doi.org/10.1164/rccm.202004-1132OCDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7781144PMC
January 2021

Obesity Is Associated With Increased Basal and Postprandial β-Cell Insulin Secretion Even in the Absence of Insulin Resistance.

Diabetes 2020 10 10;69(10):2112-2119. Epub 2020 Jul 10.

Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO

We tested the hypothesis that obesity, independent of insulin resistance, is associated with increased insulin secretion. We compared insulin kinetics before and after glucose ingestion in lean healthy people and people with obesity who were matched on multiorgan insulin sensitivity (inhibition of adipose tissue lipolysis and glucose production and stimulation of muscle glucose uptake) as assessed by using a two-stage hyperinsulinemic-euglycemic pancreatic clamp procedure in conjunction with glucose and palmitate tracer infusions and positron emission tomography. We also evaluated the effect of diet-induced weight loss on insulin secretion in people with obesity who did not improve insulin sensitivity despite marked (∼20%) weight loss. Basal and postprandial insulin secretion rates were >50% greater in people with obesity than lean people even though insulin sensitivity was not different between groups. Weight loss in people with obesity decreased insulin secretion by 35% even though insulin sensitivity did not change. These results demonstrate that increased insulin secretion in people with obesity is associated with excess adiposity itself and is not simply a compensatory response to insulin resistance. These findings have important implications regarding the pathogenesis of diabetes because hyperinsulinemia causes insulin resistance and insulin hypersecretion is an independent risk factor for developing diabetes.
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http://dx.doi.org/10.2337/db20-0377DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7506835PMC
October 2020

In vivo Characterization of Four F-Labeled S1PR1 Tracers for Neuroinflammation.

Mol Imaging Biol 2020 10;22(5):1362-1369

Department of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., St. Louis, MO, 63110, USA.

Purpose: The sphingosine-1-phosphate receptor 1 (S1PR1) is an important biomarker for imaging inflammation in the central nervous system (CNS). Herein, we report our recent evaluation of four F-labeled S1PR1 tracers (F-TZ43113, F-TZ35104, F-TZ4877, and F-TZ4881) in a rat model of multiple sclerosis (MS).

Procedures: MicroPET studies of each tracer's uptake and kinetics were performed in an experimental autoimmune encephalomyelitis (EAE) rat model of MS to quantify upregulated S1PR1 expression in the lumbar spinal cord of EAE rats. Western blot analysis was conducted to confirm the differences in the expression of S1PR1 protein level between EAE and sham rats. Radiometabolite analysis was performed for the most promising candidate in rats.

Results: All four S1PR1 tracers detected increased S1PR1 levels in response to neuroinflammation in the lumbar spinal cord of EAE rats, which was supported by western blot results. The ranked order of tracer uptake in rat spinal cord was F-TZ4877 > F-TZ4881 > F-TZ35104 > F-TZ43113. F-TZ4877 had the highest uptake of the four tracers and showed good kinetic modeling fits in rat spinal cord using an image-based method of arterial blood input function. Radiometabolite analysis of F-TZ4877 showed good in vivo stability with no major radiometabolite accumulation in the rat brain.

Conclusion: Among these four new PET tracers, F-TZ4877 showed the most favorable profile for assessing S1PR1 expression in the EAE rat model of MS. Further characterization of these radiotracers in other models of neuroinflammation is warranted to identify a promising F-labeled tracer for imaging S1PR1 in vivo.
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http://dx.doi.org/10.1007/s11307-020-01514-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7679043PMC
October 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 06 9;13(6):e011203. Epub 2020 Jun 9.

Editor in Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.011203DOI Listing
June 2020

Targeted PET Imaging of Chemokine Receptor 2-Positive Monocytes and Macrophages in the Injured Heart.

J Nucl Med 2021 Jan 22;62(1):111-114. Epub 2020 May 22.

Department of Radiology, Washington University School of Medicine, St. Louis, Missouri

Proinflammatory macrophages are important mediators of inflammation after myocardial infarction and of allograft injury after heart transplantation. The aim of this study was to image the recruitment of proinflammatory chemokine receptor 2-positive (CCR2+) cells in multiple heart injury models. Cu-DOTA-extracellular loop 1 inverso (ECL1i) PET was used to image CCR2+ monocytes and macrophages in a heart transplantation mouse model. Flow cytometry was performed to characterize CCR2+ cells. Autoradiography on a human heart specimen was conducted to confirm binding specificity. Cu- and Ga-DOTA-ECL1i were compared in an ischemia-reperfusion injury mouse model. Cu-DOTA-ECL1i showed sensitive and specific detection of CCR2+ cells in all tested mouse models, with efficacy comparable to that of Ga-DOTA-ECL1i. Flow cytometry demonstrated specific expression of CCR2 on monocytes and macrophages. The tracer binds to human CCR2. This work establishes the utility of Cu-DOTA-ECL1i to image CCR2+ monocytes and macrophages in mouse models and provides the requisite preclinical information to translate the targeted clinical-grade CCR2 imaging probe for clinical investigation of heart diseases.
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http://dx.doi.org/10.2967/jnumed.120.244673DOI Listing
January 2021

Metabolic and Molecular Imaging of the Diabetic Cardiomyopathy.

Circ Res 2020 05 21;126(11):1628-1645. Epub 2020 May 21.

Division of Radiological Sciences, Edward Mallinckrodt Institute of Radiology (R.J.G.), Washington University School of Medicine, St Louis, MO.

The term diabetic cardiomyopathy is defined as the presence of abnormalities in myocardial structure and function that occur in the absence of, or in addition to, well-established cardiovascular risk factors. A key contributor to this abnormal structural-functional relation is the complex interplay of myocardial metabolic remodeling, defined as the loss the flexibility in myocardial substrate metabolism and its downstream detrimental effects, such as mitochondrial dysfunction, inflammation, and fibrosis. In parallel with the growth in understanding of these biological underpinnings has been developmental advances in imaging tools such as positron emission tomography and magnetic resonance imaging and spectroscopy that permit the detection and in many cases quantification, of the processes that typifies the myocardial metabolic remodeling in diabetic cardiomyopathy. The imaging readouts can be obtained in both preclinical models of diabetes mellitus and patients with diabetes mellitus facilitating the bi-directional movement of information between bench and bedside. Moreover, imaging biomarkers provided by these tools are now being used to enhance discovery and development of therapies designed to reduce the myocardial effects of diabetes mellitus through metabolic modulation. In this review, the use of these imaging tools in the patient with diabetes mellitus from a mechanistic, therapeutic effect, and clinical management perspective will be discussed.
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http://dx.doi.org/10.1161/CIRCRESAHA.120.315899DOI Listing
May 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 05 15;13(5):e011018. Epub 2020 May 15.

Editor in Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.011018DOI Listing
May 2020

Update on COVID-19 From the Journal.

Circ Cardiovasc Imaging 2020 04 21;13(4):e010822. Epub 2020 Apr 21.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.010822DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7188060PMC
April 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 04 17;13(4):e010860. Epub 2020 Apr 17.

Editor in Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.010860DOI Listing
April 2020

CCR2 Positron Emission Tomography for the Assessment of Abdominal Aortic Aneurysm Inflammation and Rupture Prediction.

Circ Cardiovasc Imaging 2020 03 13;13(3):e009889. Epub 2020 Mar 13.

Department of Radiology (L.D., D.S., H.L., G.S.H., X.Z., R.L., J.Z., R.J.G., Y.L.), Washington University, St. Louis, MO.

Background: The monocyte chemoattractant protein-1/CCR2 (chemokine receptor 2) axis plays an important role in abdominal aortic aneurysm (AAA) pathogenesis, with effects on disease progression and anatomic stability. We assessed the expression of CCR2 in a rodent model and human tissues, using a targeted positron emission tomography radiotracer (Cu-DOTA-ECL1i).

Methods: AAAs were generated in Sprague-Dawley rats by exposing the infrarenal, intraluminal aorta to PPE (porcine pancreatic elastase) under pressure to induce aneurysmal degeneration. Heat-inactivated PPE was used to generate a sham operative control. Rat AAA rupture was stimulated by the administration of β-aminopropionitrile, a lysyl oxidase inhibitor. Biodistribution was performed in wild-type rats at 1 hour post tail vein injection of Cu-DOTA-ECL1i. Dynamic positron emission tomography/computed tomography imaging was performed in rats to determine the in vivo distribution of radiotracer.

Results: Biodistribution showed fast renal clearance. The localization of radiotracer uptake in AAA was verified with high-resolution computed tomography. At day 7 post-AAA induction, the radiotracer uptake (standardized uptake value [SUV]=0.91±0.25) was approximately twice that of sham-controls (SUV=0.47±0.10; <0.01). At 14 days post-AAA induction, radiotracer uptake by either group did not significantly change (AAA SUV=0.86±0.17 and sham-control SUV=0.46±0.10), independent of variations in aortic diameter. Competitive CCR2 receptor blocking significantly decreased AAA uptake (SUV=0.42±0.09). Tracer uptake in AAAs that subsequently ruptured (SUV=1.31±0.14; <0.005) demonstrated uptake nearly twice that of nonruptured AAAs (SUV=0.73±0.11). Histopathologic characterization of rat and human AAA tissues obtained from surgery revealed increased expression of CCR2 that was co-localized with CD68 macrophages. Ex vivo autoradiography demonstrated specific binding of Cu-DOTA-ECL1i to CCR2 in both rat and human aortic tissues.

Conclusions: CCR2 positron emission tomography is a promising new biomarker for the noninvasive assessment of AAA inflammation that may aid in associated rupture prediction.
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http://dx.doi.org/10.1161/CIRCIMAGING.119.009889DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7101060PMC
March 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 03 12;13(3):e010652. Epub 2020 Mar 12.

Editor in Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.010652DOI Listing
March 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 02 17;13(2):e010515. Epub 2020 Feb 17.

Editor-in-Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.120.010515DOI Listing
February 2020

Cardiac PET/CT-Determined Amyloid Light Chain Depositions: A New Risk Biomarker?

J Am Coll Cardiol 2020 02;75(4):391-394

Division of Cardiology, Cardio-Oncology Center of Excellence, Washington University in St. Louis School of Medicine, St. Louis, Missouri.

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http://dx.doi.org/10.1016/j.jacc.2019.11.038DOI Listing
February 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2020 01 21;13(1):e010410. Epub 2020 Jan 21.

Editor-in-Chief, Circulation: Cardiovascular Imaging.

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http://dx.doi.org/10.1161/CIRCIMAGING.119.010410DOI Listing
January 2020

Cu-ATSM Positron Emission Tomography/Magnetic Resonance Imaging of Hypoxia in Human Atherosclerosis.

Circ Cardiovasc Imaging 2020 01 8;13(1):e009791. Epub 2020 Jan 8.

Mallinckrodt Institute of Radiology (X.N., R.L., J.Z., T.F.V., N.B., J.X., R.L., R.J.G., P.K.W), Washington University School of Medicine, St Louis, MO.

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http://dx.doi.org/10.1161/CIRCIMAGING.119.009791DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7328725PMC
January 2020

In This Issue of the Journal.

Authors:
Robert J Gropler

Circ Cardiovasc Imaging 2019 12 16;12(12):e010231. Epub 2019 Dec 16.

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http://dx.doi.org/10.1161/CIRCIMAGING.119.010231DOI Listing
December 2019