Introduction
Carnosine (β-alanyl-l-histidine), containing an imidazole moiety, is an intramuscular dipeptide consisting of β-alanine and l-histidine (the molecular structure as shown in Fig 1.), which is highly concentrated in muscle and brain tissues, that are exposed to higher oxidative stress than other tissues. And it is crystalline solid and has good solubility in water. Of course, the physiological and pathological aspects of carnosine are well studied, and various functions of carnosine have been reported, including as an immune-modulator and as a neurotransmitter/modulator. In addition, supplementation with carnosine aids the treatment of chronic alcoholic liver injury and improves high-intensity sports performance.
Fig 1. The molecular structure of carnosine
Mechanism
Carnosine as antioxidants, and endogenous chelators, also inhibits protein modification by the reactive aldehydes found in advanced glycoxidation and lipoxidation end products. More specifically, Carnosine's possible biological activities include scavengers of reactive oxygen species (ROS) and reactive nitrogen species (RNS), chelating agents of zinc and copper ions, and anti-glycation and anti-cross-linking activities. The ability of carnosine to react with toxic aldehydes such as malondialdehyde, methylglyoxal, hydroxynonenal and acetaldehyde, the primary product of lipid peroxidation, may also contribute to protective function. In addition, Physiological carnosine may help to inhibit some of the secondary complications of diabetes, as well as the deleterious consequences of ischemia-reperfusion injury, which results in effects of antioxidant and carbonyl scavenge.
Effect and application
Because of carnosine's special properties and functions, it can be applied in many fields and has been a popular object for many researchers. For example, it can be added into food as an addition agent, which has been used to study its effects as an antioxidant on meat quality of pigs, and in meat processing, and it has the effect of inhibiting fat oxidation and protecting flesh color. In addition, the antioxidant with the carnosine as a raw material can be used to cure elderly cataract. Importantly, it can be wildly applied in cosmetic products to prevent skin aging and make skin white. Furthermore, carnosine can prevent ROS, a very active atom or group of atoms in the body that oxidizes other substances in the human body, caused by smoking, which will damage the skin more than sunlight.
References:
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