Fig. 3

Elastin fiber fragmentation, collagen deposition, and elastolytic activity in the aorta. a Representative pictures for the elastic fiber network, and b quantification of elastin fiber breaks in the thoracic aortic media. Arrows indicate breaks in the elastin fiber. Each scale bar is 100 μm. c Collagen stain by the polarized view of picrosirius red-stained section and d quantification of collagen proportion of the aorta. Each scale bar is 1 mm. e Expression of collagen and elastic fiber components in the aorta (n = 7, 5, and 6 for control, ob/ob, and ob/ob + Piog groups respectively). mRNA amount is expressed relative to the average expression in control mice. f Immunoblot analysis on type I collagen, tropoelastin, fibulin-4/5 in the aorta. Each band represents a tissue extract from a single mouse. g In situ zymography for elastolytic activity in the frozen section. Each scale bar is 200 μm, h Tissue lysates of aorta and PVAT for elastolytic activity assay. The elastolytic activity was demonstrated as the area under the curve (AUC) of fluorescence with normalization to protein concentration over time. All data are resulted from 3-month-old male mice. *P < 0.05 and **P < 0.01