What are lipofuscin granules?
Lipofuscin is the name given to fine yellow-brown pigment granules composed of lipid-containing residues of lysosomal digestion. It is considered to be one of the aging or “wear-and-tear” pigments, found in the liver, kidney, heart muscle, retina, adrenals, nerve cells, and ganglion cells.
What causes lipofuscin granules?
Numerous studies indicate that the formation of lipofuscin is due to the oxidative alteration of macromolecules by oxygen-derived free radicals generated in reactions catalyzed by redox-active iron of low molecular weight.
How do you remove lipofuscin?
The dissolution of lipofuscin is not only found in the CNS but also in the myocardium and in the liver. In the latter organs the removal of pigment is carried out by phagocytes towards capillaries. The actual uptake of phagocytes is believed to occur by the process of exocytosis and pinocytosis.
Is lipofuscin endogenous?
Endogenous pigments are characterized as hematogenous and nonhematogenous. Examples of endogenous hematogenous pigments found in the liver are hemosiderin and bilirubin. Examples of endogenous nonhematogenous pigments found in the liver are lipofuscin (fatlike) and copper (non-fatlike).
Is lipofuscin normal?
Abstract. Lipofuscin is highly fluorescent material, formed in several tissues but best studied in the eye. The accumulation of lipofuscin in the retinal pigment epithelium (RPE) is a hallmark of aging in the eye and has been implicated in various retinal degenerations, including age-related macular degeneration.
Why is lipofuscin bad?
Composed of lipids, proteins, and a number of chromophores, lipofuscin is highly susceptible to photochemical changes that can produce permanent cellular damage.
Does drusen lead to macular degeneration?
Small drusen may not cause problems for some people, but larger drusen can increase your risk of a medical condition called age-related macular degeneration (AMD). Drusen can be a sign that you already have age-related macular degeneration.
Is lipofuscin drusen?
As the RPE ages some of the changes that can occur are accumulation of lipofuscin (LF) and the formation of drusen. Lipofuscin is actually debris that comes from the normal shedding of an outer portion of rods and cones. A healthy RPE can digest this waste and remove it.
Is autofluorescence a good marker of lipofuscin?
The most characteristic feature of lipofuscin is its autofluorescence. The chemical nature and structure of lipofuscin have not yet been well understood, but the autofluorescence has been regarded as the most reliable qualitative and quantitative marker of lipofuscin.
Is lipofuscin autofluorescent in the brain and adrenal?
Lipofuscin is the autofluorescent material, which accumulates with aging in the cells of various tissues. However, its autofluorescence characteristics are different among tissues. In the present study, the autofluorescence features of lipofuscin in the brain and adrenal were compared.
What is the emission range of brain lipofuscin?
The emission maximum of the bright whitish-yellow brain lipofuscin was 540 nm to 570 nm and that of the adrenal lipofuscin was 640 nm to 660 nm, when excited at 330 nm to 380 nm.
What does lipofuscin look like in the brain?
The autofluorescence of lipofuscin in the neurons of the pons was bright whitish-yellow, but some lipofuscin granules appeared bright orange. Bar: 50 μm.