pH buffer Carnosine has a pKa value of 6.83, making it a good
buffer for the pH range of animal muscles. Since beta-alanine is not incorporated into proteins, carnosine can be stored at relatively high concentrations (millimolar). Occurring at 17–25 mmol/kg (dry muscle), carnosine (β-alanyl-L-histidine) is an important intramuscular buffer, constituting 10–20% of the total buffering capacity in type I and II muscle fibres.
Anti-oxidant Carnosine has been shown to scavenge
reactive oxygen species (ROS) as well as alpha-beta unsaturated
aldehydes formed from peroxidation of cell membrane
fatty acids during
oxidative stress. It also buffers pH in muscle cells, and acts as a neurotransmitter in the brain. It is also a
zwitterion, a neutral molecule with a positive and negative end.
Antiglycating Carnosine acts as an antiglycating agent, reducing the rate of formation of
advanced glycation end-products (substances that can be a factor in the development or worsening of many
degenerative diseases, such as
diabetes,
atherosclerosis,
chronic kidney failure, and
Alzheimer's disease), and ultimately reducing development of atherosclerotic plaque build-up.
Geroprotective Carnosine is considered as a
geroprotector. Carnosine can increase the
Hayflick limit in human
fibroblasts, as well as appearing to reduce the
telomere shortening rate. Carnosine may also slow aging through its anti-glycating properties (chronic glycolyating is speculated to accelerate aging).
Other Carnosine can
chelate divalent metal ions. It has been suggested that binding Ca2+ may displace protons, thereby providing a link between Ca2+ and H+ buffering. However, there is still controversy as to how much Ca2+ is bound to carnosine under physiological conditions. ==See also==