Figure 4.

NTM infection induces cardiac fibrosis in old mice. Heart sections from sham and Mycobacterium avium infected young and old mice were stained with Masson's trichrome to identify fibrosis in cardiac tissue. Image shown here are representative of whole heart and interstitial fibrosis from sham‐treated young (a) and old (c) mice that were infected with M. avium (b and d). The image shown in right panel is 40× magnification and representative of five animals/group. The trichrome staining (blue color) in the heart sections was isolated using Photoshop CC in color range selection mode. The total intensity of the stained area in the heart sections was further quantified via ImageJ using color intensity to multiply area with staining. Graph shown in (e) young mice sham‐treated and M. avium infected, (f) old mice sham‐treated M. avium infected, and (g) comparison of M. avium infected young and old mice. Data shown in graphs are cumulative data from five animals (mean ± SEM; ** p < 0.005; ***p < 0.0005; N = 5)