Aging is associated with increased oxidative stress, which contributes to cellular dysfunction and age-related diseases. Pomegranate extract (PE), rich in antioxidant polyphenols, may help mitigate oxidative damage. This study evaluated whether PE supplementation modulates oxidative stress by reducing reactive oxygen species (ROS) levels in white blood cells of aging mice. Aged mice (18 months) were supplemented with PE for four months, and cytoplasmic and mitochondrial ROS levels were assessed in leukocytes under basal conditions and oxidative stress conditions induced by tert-butyl hydroperoxide (t-BHP) using flow cytometry. Our results indicate that aged mice exhibit increased basal ROS levels in both the mitochondrial and cytoplasmic compartments, which were mitigated by PE supplementation. Furthermore, PE reversed the increase in hydrogen peroxide levels induced by τ-BHP and protected neutrophils by reducing mitochondrial ROS levels. These findings suggest that PE supplementation modulates the oxidative stress response, potentially improving immune function in aging. Given the central role of oxidative stress in age-related decline, PE may represent a valuable nutritional strategy to promote healthy aging.

Background/Objectives: Unlike post-mortem histopathology, cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) enable longitudinal assessment of structural, functional, and metabolic alterations in preclinical myocardial infarction models. This study aims to describe the temporal evolution of infarct size and systolic function by CMR and glucose consumption via PET, explore their differences in non-reperfused and reperfusion infarction models, and assess their capacity to predict histology-derived infarct size and systolic function at chronic phase CMR. Methods: Two murine models of myocardial infarction were generated using permanent (non-reperfused, n = 8) or transient (reperfused, n = 9) coronary occlusion. CMR and fluorine-18 2-fluoro-2-deoxyglucose PET imaging were performed at baseline and at 1, 7, and 21 days post-infarction to quantify infarct size, systolic function, and myocardial glucose metabolism. Infarct size was also assessed using Masson’s trichrome staining. Results: At 24 h post-infarction, CMR-derived infarction together with significant reduction in systolic function and glucose metabolism were already noted in both models. At 21-day CMR, however, reperfused mice showed lower infarct size and more preserved systolic function compared to their non-reperfused counterparts, while no differences in glucose metabolism were reported. Infarct size and systolic function at 1-day CMR and the number of segments with reduced glucose consumption at 1-day PET independently predicted histology-derived infarct size and long-term systolic function. Conclusions: Combined PET/CMR imaging enables non-invasive, sequential evaluation of infarct size, systolic function, and glucose metabolism in experimental myocardial infarction. This multimodality approach is well suited for assessing the efficacy of emerging therapies in preclinical research.

Introduction: To evaluate [18F]Fluodeoxyglucose ([18F]FDG) distribution in a murine model of myocardial infarction (MI), using Positron Emission Tomography and Computed Tomography (PET/CT) to validate this approach for use in evaluating new therapies for MI treatment. Method: MI was induced by permanent ligation of the left anterior descending coronary artery. The study included a sham group, a group with 7 days infarction (acute infarction) and another with 21 days infarction (chronic infarction). Prior to euthanasia, each group was imaged by PET/CT approximately 60 minutes after injection of [18F]FDG. Total and maximal Region of Interest and Standard Uptake Value values were obtained using CT, which enables more precise delineation of the anatomy to assess between-group differences in [18F]FDG uptake in the heart, brain and bladder. Results: Following distribution of [18F]FDG throughout the body, at 60 minutes after injection homogeneous cardiac distribution of the radiopharmaceutical was observed in the healthy group, while in the infarcted groups there was an absence of uptake in the infarct area. Using ANOVA analysis and the Kruskal-Wallis test, statistically significant differences were detected between the healthy and acute infarction groups and the acute and chronic infarction groups. There were no significant differences between the three groups in brain uptake or radiopharmaceutical clearance. Conclusions: The microPET/CT technique has the sensitivity to detect infarcted areas in the murine model. Moreover, it allows us to quantify [18F]FDG uptake and thus assess uptake by the organs in the different groups studied.