Figure 4. Western diet feeding resulted in myocardial interstitial fibrosis and oxidative stress that were prevented by volitional exercise.
A) Quantification of picrosirus red staining alongside representative images for both WD and WD+Ex groups reveals a significant increase in interstitial collagen deposition (pink color) in WD fed mice that was prevented by exercise. Quantification of myocardial fibrosis reveals a significant reduction in interstitial fibrosis with exercise (Dashed line represents average value of control diet fed mice. N = 5 for WD group and N = 6 for WD+Ex group. * denotes p <0.01 for WD compared to WD+Ex.) B) Quantification of 3-nitrotyrosine staining alongside representative images for both WD and WD+Ex groups shows marked accumulation of peroxynitrite, an oxidant species, (dark brown color) that was prevented by volitional exercise. Quantification of 3-NT staining by average gray scale intensities showed amelioration of oxidant stress with exercise in WD fed mice. (Dashed line represents average value of non-exercised control diet fed mice. N = 6 for WD group and N = 7 for WD+Ex group. * denotes p < 0.01 for WD compared to WD+Ex.)