S-EPMC7329622 - Changes in microarchitecture of atherosclerotic calcification assessed by <sup>18</sup>F-NaF PET and CT after a progressive exercise regimen in hyperlipidemic mice. - OmicsDI

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Dataset Information

Changes in microarchitecture of atherosclerotic calcification assessed by ¹⁸F-NaF PET and CT after a progressive exercise regimen in hyperlipidemic mice.

ABSTRACT:

Background

Despite the association of physical activity with improved cardiovascular outcomes and the association of high coronary artery calcification (CAC) scores with poor prognosis, elite endurance athletes have increased CAC. Yet, they nevertheless have better cardiovascular survival. We hypothesized that exercise may transform vascular calcium deposits to a more stable morphology.

Methods

To test this, hyperlipidemic mice (Apoe^-/-) with baseline aortic calcification were separated into 2 groups (n = 9/group) with control mice allowed to move ad-lib while the exercise group underwent a progressive treadmill regimen for 9 weeks. All mice underwent blood collections and in vivo ¹⁸F-NaF μPET/μCT imaging both at the start and end of the exercise regimen. At euthanasia, aortic root specimens were obtained for histomorphometry.

Results

Results showed that, while aortic calcification progressed similarly in both groups based on µCT, the fold change in ¹⁸F-NaF density was significantly less in the exercise group. Histomorphometric analysis of the aortic root calcium deposits showed that the exercised mice had a lower mineral surface area index than the control group. The exercise regimen also raised serum PTH levels twofold.

Conclusion

These findings suggest that weeks-long progressive exercise alters the microarchitecture of atherosclerotic calcium deposits by reducing mineral surface growth, potentially favoring plaque stability.

SUBMITTER: Hsu JJ

PROVIDER: S-EPMC7329622 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Changes in microarchitecture of atherosclerotic calcification assessed by <sup>18</sup>F-NaF PET and CT after a progressive exercise regimen in hyperlipidemic mice.

Hsu Jeffrey J JJ Fong Felicia F Patel Radha R Qiao Rong R Lo Karen K Soundia Akrivoula A Chang Chih-Chiang CC Le Victoria V Tseng Chi-Hong CH Demer Linda L LL Tintut Yin Y

Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology 20200102 5

<h4>Background</h4>Despite the association of physical activity with improved cardiovascular outcomes and the association of high coronary artery calcification (CAC) scores with poor prognosis, elite endurance athletes have increased CAC. Yet, they nevertheless have better cardiovascular survival. We hypothesized that exercise may transform vascular calcium deposits to a more stable morphology.<h4>Methods</h4>To test this, hyperlipidemic mice (Apoe<sup>-/-</sup>) with baseline aortic calcificati ...[more]

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