Age Pigment (Lipofuscin)

Age Pigment (Lipofuscin) is the brown material that forms spots on aging skin, and accumulates in various organs, causing their functions to deteriorate with age. It is made up of oxidized unsaturated oils with iron 1. This pigment is a result of the convergence of toxic effects from unsaturated oils, estrogen, and excess iron, creating a "terminal toxin" that produces the essential features of aging 2.

The formation of age pigment is accelerated by pro-oxidant metals, especially iron, and has been demonstrated in various experiments 4. Hartroft and Porta (1967) found that iron accelerates the formation of age pigment, and recent experiments confirm these observations 4. Aluminum and silicon, which have a role in brain and blood vessel aging, also contribute to the formation of age pigment 4.

Estrogen causes changes in collagen synthesis that resemble changes occurring in aging and oxygen deprivation 5. Estrogen also makes cellular water more "bulk-phase" like, with less of the structure evident in water near surfaces, which may contribute to its damaging effects on mitochondria 5.

The pigment cells responsible for age pigment are highly mobile and can swim through solid tissue at a surprising speed 6. However, there is limited knowledge about the interactions between diet, stress, and hormones on lipofuscin removal, and more research is needed in this area 6.

In senescent hamsters, the uterus shows increased TTC reduction, which is a result of an active physiological process or malfunction 7. The formation of age pigment has been studied in senescent uteri, where it was found to be heavily pigmented and could be extracted using diethyl ether or pyridine 8.