:Carbonylation:

:Our body is made up largely of proteins. Because the body's antioxidant system and other lines of defense cannot completely protect proteins, they tend to undergo destructive changes as we age, due largely to oxidation, glycation and another process called carbonylation. Carbonyl groups can (>C=O) bond to protein molecules and phospholipids. This causes proteins to break up in a process known as proteolysis. Since protein carbonylation precedes the loss of membrane integrity, it may be associated with the toxic process leading to cell senescence and death.

Protein denaturation and proteolysis involves oxidation, carbonylation, cross-linking, glycation and advanced glycation endproduct (AGE) formation. These aging processes cause skin aging, cataracts and neurodegeneration. Studies show that Carnosine, a unique dipeptide, is uniquely effective against all these forms of protein denaturation. Carnosine reacts with the carbonyl group and forms an inert protein-carbonyl-carnosine compound, protecting proteins and reversing denaturation.

AGE-inhibitors quench the carbonyl reactions and chelate metals, preventing them from acting as catalysts in further oxidation and AGE formation (Price et al. 2001).

Carnosine restores normal cell cycle control for removal of spent parts. Without this cleanup, the efficiency of cell division (regeneration) is impaired and chromosomes become unstable, leading to degeneration (cellular senescence) or cancer.

While other antioxidants suppress some of the many pathways involved, they have no effect upon others, like glycation and carbonylation.
These chemical side-reactions that erode biological structure and function in the course of aging result from toxic effects of the most basic elements in the body’s chemistry: oxygen, sugars, lipids and essential metals. We cannot do without these biochemical elements, but nutritional science is now providing better control of their side effects.

Phospholipids are carbonylated as well, causing damage especially in the central and peripheral nervous systems, and deterioration of cognitive skills including memory loss. As carnosine fights carbonylation of phospholipids as well, it is excellent for neuroprotection.