Figure 3

Myocardial inflammation at sacrifice. (A) Frequency histograms of semiquantitative inflammation scoring in the continued EEX study. The scoring distribution was significantly different between all groups in general (P < 0.001; Monte Carlo Pearson Chi-Square), but not between CVB-EEX and CVB-SED, neither for all inflammatory categories (P = 0.919; Monte Carlo linear-by-linear association), nor with regard to cardiomyocyte loss (focal vs. confluent) (P = 0.650; Monte Carlo Pearson Chi-Square). The odds ratio for confluent loss of cardiomyocytes was 2.33 (95% CI 0.37–14.71) in CVB-EEX compared to CVB-SED. Abbreviations: inf., infiltration; IS, interstitial; NS, not significant; PV, perivascular. (B) Inflammation area in the continued EEX study. The median values are displayed in numbers above each box-and-whiskers plot. The Kruskal–Wallis test was used for statistical analysis, followed by Dunn’s multiple comparisons test. Group size: PBS-SED: n = 14; PBS-EEX: n = 14; CVB-SED: n = 16; CVB-EEX: n = 17. (C) Semiquantitative inflammation scoring in the pretrained EEX study as represented by frequency histograms. The scoring distribution was compared between preEEX-CVB and preSED-CVB by means of the Monte Carlo linear-by-linear association test (P = 0.290). (D) Inflammation area in the pretrained EEX study. The median values are displayed in numbers above each box-and-whiskers plot. The Mann–Whitney U test was used for statistical analysis. Group size: preSED-PBS: n = 5; preEEX-PBS: n = 4; preSED-CVB: n = 7; preEEX-CVB: n = 9. (E) Morphological examples of inflammatory lesions in exercising and sedentary CVB mice in the continued EEX study. On HE staining, there was more cellularity of the lesions in the exercising (right panel) compared to the sedentary group (left panel). Evidence for organisation of the lesions (haemosiderin-laden macrophages and spindled interstitial cells) was seen in both groups.