Dataset Information

SPECT Imaging of Muscle Injury with [^99mTc]MDP in a Mouse Model of Muscular Dystrophy.

ABSTRACT:

Purpose

Tc-99m methylene diphosphonate ([^99mTc]MDP) is an in vivo bone imaging agent that also accumulates in injured skeletal muscle cells. The objective of this study was to investigate if [^99mTc]MDP could be used to detect muscle injury in the mdx mouse model of Duchenne muscular dystrophy (DMD).

Procedures

Static whole-body single-photon emission computed tomography/computed tomography (CT) scans were acquired at 2 h post-injection of [^99mTc]MDP in two cohorts of animals at different sites: one cohort of mice at 6, 15, and 19 weeks of age, and a separate cohort at 16 weeks. The second cohort was also imaged with high-resolution CT at 8 weeks.

Results

mdx mice had higher [^99mTc]MDP uptake and significantly higher [^99mTc]MDP concentrations in muscle than controls.

Conclusions

Higher uptake of [^99mTc]MDP in muscle of mdx mice agrees with histological reports of muscle calcification in mdx mice, and suggests the potential translational use of [^99mTc]MDP imaging for tracking DMD progression and therapeutic response.

SUBMITTER: Gaut C

PROVIDER: S-EPMC7250810 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Publications

SPECT Imaging of Muscle Injury with [<sup>99m</sup>Tc]MDP in a Mouse Model of Muscular Dystrophy.

Gaut Carolynn C Sullivan Jenna M JM Biscaro Barbara B Soares Edward J EJ Nicholson Katharine K Hoppin Jack J Verma Ajay A

Molecular imaging and biology 20200601 3

<h4>Purpose</h4>Tc-99m methylene diphosphonate ([<sup>99m</sup>Tc]MDP) is an in vivo bone imaging agent that also accumulates in injured skeletal muscle cells. The objective of this study was to investigate if [<sup>99m</sup>Tc]MDP could be used to detect muscle injury in the mdx mouse model of Duchenne muscular dystrophy (DMD).<h4>Procedures</h4>Static whole-body single-photon emission computed tomography/computed tomography (CT) scans were acquired at 2 h post-injection of [<sup>99m</sup>Tc]MD ...[more]

PMID: 31286350

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Project description:AimIdiopathic pulmonary fibrosis (IPF) is associated with a poor prognosis, presenting the most aggressive form of interstitial lung diseases (ILDs). Activated fibroblasts are crucial for pathological processes. Fibroblast activation protein (FAP) inhibitor (FAPI) tracers would be promising imaging agents for these diseases. The purpose of this study was to evaluate a 99mTc-labeled FAPI tracer, 99mTc-HFAPI imaging in IPF patients.MethodsEleven IPF patients (nine males and two females; age range 55-75 year) were included in this pilot study. 99mTc-HFAPI serial whole-body scintigraphy at 5 min, 20 min, 40 min, 1 h, 2 h, 3 h, 4 h, and 6 h was acquired for dynamic biodistribution and dosimetry estimation in seven representative patients. SPECT/CT tomography fusion imaging of the chest region was performed in all patients at 4 h post-injection, which was considered as the optimal acquisition time. Dosimetry was calculated using OLINDA/EXM software (version 2.0; HERMES Medical Solutions). The quantified or semi-quantified standardized uptake values (SUVs) and lesion-to-background ratios (LBRs) of affected lung parenchyma were also calculated. The high-resolution CT (HRCT) stage was determined with visual evaluation, and the total HRCT score of each patient was measured using a weighting factor formula. Pulmonary function tests (PFTs) were recorded as well. Then, the relationships between the 99mTc-HFAPI results, disease extent on HRCT, and PFT results were investigated.ResultsNormal physiological uptake of 99mTc-HFAPI was observed mainly in the liver, intestinal tract, pancreas, gallbladder, and to a lesser extent in the spleen, kidneys, and thyroid, with no apparent retention in the blood circulation at the late time point. The mean injected activity of 99mTc-HFAPI was 813.4 MBq (range 695.6-888.0 MBq). No subjective side effects were noticed. The average whole-body effective dose was 0.0041 mSv/MBq per patient. IPF patients exhibited elevated pulmonary 99mTc-HFAPI uptake in abnormal lung regions, which was correlated with fibrotic regions on HRCT. Among different HRCT stage groups, both SUVmax and LBR showed significant differences (p < 0.001). The higher HRCT stage demonstrated significantly higher SUVmax and LBR. A linear correlation between 99mTc-HFAPI uptake and total HRCT score was observed for SUVmax (r = 0.7839, F = 54.41, p = 0.0094) and LBR (r = 0.7402, F = 56.33, p = 0.0092). 99mTc-HFAPI uptake also had moderate correlations with PFT results.ConclusionsOur preliminary data show that the 99mTc-HFAPI SPECT imaging is a promising new imaging modality in IPF patients. Investigations of its clinical value in monitoring disease progression and treatment response are needed in the future.

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Dataset Information

SPECT Imaging of Muscle Injury with [^99mTc]MDP in a Mouse Model of Muscular Dystrophy.

Purpose

Procedures

Results

Conclusions

Publications

SPECT Imaging of Muscle Injury with [<sup>99m</sup>Tc]MDP in a Mouse Model of Muscular Dystrophy.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

SPECT Imaging of Muscle Injury with [99mTc]MDP in a Mouse Model of Muscular Dystrophy.

Purpose

Procedures

Results

Conclusions

Publications

SPECT Imaging of Muscle Injury with [<sup>99m</sup>Tc]MDP in a Mouse Model of Muscular Dystrophy.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

SPECT Imaging of Muscle Injury with [^99mTc]MDP in a Mouse Model of Muscular Dystrophy.