age pigment in the brain of the European lobster, Homarus gammarus.
Another common abnormal feature of the post-mortem diaphragms was cytoplasmic abnormalities in muscle cells, which included uneven cytoplasmic staining, vacuolization, inflamed cells, hyaline fibers, and lipofuscin
. Vacuolization can represent a loss of myosin or inclusions of substances like lipid or glycogen.
We hypothesize that lipofuscin
can provide a more robust measure of age than current size-based measures.
This cellular gunk is called lipofuscin
. Lipofuscin-filled lysosomes slowly crowd and hinder other cellular functions.
Her next step is to take sections through the animals' eye-stalk and brain tissue and look for fluorescing lipofuscin
granules using an epifluorescence microscope.
Why: They are high in nutrients, such as beta carotene, which destroy the pigment lipofuscin
that causes the spots.
Ultrastructure of lipofuscin
granules in normal human skeletal muscles.
With ageing, the lipid products of phagocytosis accumulate within the RPE as the age pigment lipofuscin
. It has been postulated that in old age, this material is released from the RPE and renders the overlying Bruch's membrane hydrophobic.
In Best's disease, the macula becomes coated with a yellowish substance called lipofuscin
, which obstructs progressively larger regions of the retina as an individual ages.
(10) Parallel to senescence of retinal pigment epithelial cells, lipofuscin
begins to accumulate in the cytoplasm due to slowing lysosomal activities, resulting in a vicious cycle.
Mutations in retinol metabolism and 3',5'-cyclic-GMP phosphodiesterase activity affected the visual cycle and may block the recycling of all-trans-retinal to 11-cis-retinal, generating photooxidative damage and depositing the ocular pigment lipofuscin
Fundus autofluorescence (FAF) is used to study the accumulation of lipofuscin
granules within the RPE.