They figure prominently not only in the processes of aging but also in its familiar signs such as skin aging, cataracts and neurodegeneration. Studies show that carnosine is effective against all these forms of protein modification. As an antioxidant, carnosine potently quenches that most destructive of free radicals, the hydroxyl radical, as well as superoxide, singlet oxygen and the peroxyl radical. Carnosine's ability to rejuvenate connective tissue cells may explain its beneficial effects on wound healing. In addition, skin aging is bound up with protein modification.
Damaged proteins accumulate and cross-link in the skin, causing wrinkles and loss of elasticity.
In the lens of the eye, protein cross-linking is part of cataract formation. Carnosine levels decline with age. Since carnosine acts as a pH buffer, it can keep on protecting muscle cell membranes from oxidation under the acidic conditions of muscular exertion. The body is made up largely of proteins. Unfortunately, proteins tend to undergo destructive changes as we age, due largely to oxidation and interactions with sugars or aldehydes.