“…It occurs in a variety of tissues and cell types, such as neurons, myocardiocytes, hepatocytes, skeletal muscle and smooth muscle [ 6 , 10 ]. Lipofuscin deposition in smooth muscle are reported in some cases, such as brown bowel syndrome in humans, brown gut in dogs, and ceroid-lipofuscinosis, an inherited lysosomal storage disease, in several animal species [ 2 , 3 , 5 , 7 , 8 , 9 , 11 ]. To our knowledge, however, there has been no report describing vascular smooth muscle lipofuscinosis occurring predominantly in the veins of primates including humans.…”