Figure 1.

Picrosirius red staining in the human muscle samples. (A): muscle sample from an 87 year old man with fat infiltration (*); (B): muscle sample from a 94 year old woman with muscle atrophy (^#). The collagen intensity and the disposition of the fibers stained (in red) are shown in young subjects ((C), 18 year old male; (E), 32 year old male) and in elderly men ((D), 83 years old; (F), 94 year old male). The altered arrangement of the collagen fibers can be noted in the older subject (arrows). The analysis of the collagen content (G) showed the higher amount of collagen in elderly men with respect to young men (** p < 0.01). M = muscle cell, peri: perimysium, endo: endomysium. Scale bar: 50 μm.