Carnosine-based supplement

Carnosine (β-alanyl-L-histidine) (Fig 1) is a cytoplasmic dipeptide synthesized from the precursors L-histidine and β-alanine by carnosine synthetase and degraded by carnosinase which regulates its cellular level. Carnosine is present in relatively high concentrations in skeletal muscle (5–10 mM) and other excitable tissues, such as nervous tissue. Given that the pKa of the imidazole ring is 6.83, carnosine acts as a physicochemical buffer in myocytes. This function is consistent with the fact that carnosine is present in higher concentrations in glycolytic than in oxidative muscle fibers, with the highest levels found in animals that perform frequent sprint exercises (e.g., greyhounds, thoroughbred horses), explosive flight behaviors (e.g., pheasants), and prolonged hypoxic dives (e.g., whales) (1). Recent studies have described other biological roles for carnosine such as antioxidant, antidiabetic (reduction of glycation), anti-aging (lengthening of chromatid telomere), anti-cataract (when administered as eye-drops) and anti-autism (2). The present paper reviews some recent studies on the role of carnosine in athletes and in the elderly and adds some preliminary results from athletes in acute and stressed conditions where lactic acid is produced.