Lipofuscin is best described as:

Lipofuscin is best described as:

• A. A stress pigment that indicates active pathology in aging hearts.
• B. Wear-and-tear pigment; golden-brown granules in aging myocytes; not necessarily pathologic.
• C. A pigment associated with iron overload in cardiomyocytes.
• D. A lipid-rich pigment found in macrophages during atherosclerosis.

Answer: (B)

Lipofuscin is an aging pigment that forms from the cumulative digestion products of lysosomes—basically remnants of autophagy of damaged membranes. It consists of lipid-containing residues and appears as brownish-gold granules within the cytoplasm of long-lived cells, especially aging cardiac myocytes (and neurons). Because it accumulates with age and does not disrupt cell function, it is considered a marker of cellular wear-and-tear rather than a sign of active disease. It is inert and not caused by iron overload or lipid-laden macrophages in atherosclerosis; those are different pigments and processes. Therefore, the description that best fits is that lipofuscin is the wear-and-tear pigment seen as golden-brown granules in aging myocytes, not necessarily pathologic.

Lipofuscin is an aging pigment that forms from the cumulative digestion products of lysosomes—basically remnants of autophagy of damaged membranes. It consists of lipid-containing residues and appears as brownish-gold granules within the cytoplasm of long-lived cells, especially aging cardiac myocytes (and neurons). Because it accumulates with age and does not disrupt cell function, it is considered a marker of cellular wear-and-tear rather than a sign of active disease. It is inert and not caused by iron overload or lipid-laden macrophages in atherosclerosis; those are different pigments and processes. Therefore, the description that best fits is that lipofuscin is the wear-and-tear pigment seen as golden-brown granules in aging myocytes, not necessarily pathologic.