Lipofuscin Accumulation in Myocytes

Introduction to Lipofuscin

• Lipofuscin is a yellowish-brown, autofluorescent, protein and lipid-containing pigment that accumulates progressively over time in lysosomes of postmitotic cells, particularly in cardiac myocytes, neurons, and other non-dividing cells 1

Detection and Evaluation

• Lipofuscin can be detected through autofluorescence detection, Sudan Black B staining, Schmorl staining, and immunohistochemistry for 4-hydroxynonenal (4-HNE) 1
• When evaluating myocytes with focal lipofuscin pigmentation, consideration should be given to the patient's age, distribution pattern, and associated findings such as signs of myocyte hypertrophy, fibrosis, inflammatory infiltrates, and other structural abnormalities 2

Clinical Significance

• Excessive lipofuscin accumulation can cause oxidative stress, impair lysosomal function, contribute to cellular senescence, and potentially lead to cell death 1
• The American Heart Association recommends considering the patient's age, cardiac function, and other histopathological findings when interpreting lipofuscin accumulation 2

Potential Interventions

• Enhancing autophagy and antioxidant strategies may be potential interventions for excessive lipofuscin accumulation, although more research is needed to fully understand their effectiveness 1
• The European Society of Cardiology suggests that rapamycin treatment has shown effectiveness in reducing lipofuscin accumulation and myocardial senescence in experimental models, but more research is needed to confirm its efficacy in humans 2