Carnosine is a small molecule composed of the amino acids histidine and alanine. Carnosine is found in relatively high concentrations in several body tissues, most notably in skeletal muscle, heart muscle, nerve tissue and the brain. The exact biological role of carnosine is not well understood, but many studies indicate that carnosine has antioxidant potential.
Carnosine may also act as a neurotransmitter (chemical messenger in the nervous system). It has been called a longevity nutrient since laboratory studies on tissues indicate that it can delay senescence and provoke cellular rejuvenation in cultured human fibroblasts. Carnosine has been called the anti-aging and antioxidant dipeptide.
L-Carnosine is a dipeptide composed of the covalently bonded amino acids alanine and histidine and is found in the brain, heart, skin, muscles, kidneys and stomach to name a few. L-Carnosine is naturally produced in the body by the enzyme carnosine synthetase.
Carnosine is present in high concentrations in human skeletal muscles. The oral ingestion of beta-alanine, the rate-limiting precursor in carnosine synthesis, has been shown to elevate the muscle carnosine content both in trained and untrained humans. Little human data exist about the dynamics of the muscle carnosine content, its metabolic regulation, and its dependence on muscle fiber type.
The present study aimed to investigate in three skeletal muscle types the supplementation induced amplitude of carnosine synthesis and its subsequent elimination on cessation of supplementation (washout). Fifteen untrained males participated in a placebo controlled double blind study. They were supplemented for 5 to 6 weeks with either 4.8 g/day beta-alanine or placebo.
The beta-alanine supplementation significantly increased the carnosine content in soleus by 39%, in tibialis by 27%, and in gastrocnemius by 23% and declined post supplementation at a rate of 2 to 4% per week. Average muscle carnosine remained increased compared with baseline at 3 weeks of washout (only one third of the supplementation induced increase had disappeared) and returned to baseline values within 9 weeks at group level.
It can be concluded that carnosine is a stable compound in human skeletal muscle and confirming the absence of carnosinase in myocytes. This study shows that washout periods in supplementation studies for muscle metabolites may sometimes require months rather than weeks.
As research continues on this amino acid combination, those who whish to supplement with Carnosine can know that after a loading phase of 2 to 3 weeks one can back off the quantity to once every other day to maintain levels throughout the body. Quality amino acids can be found in health food stores by the brand name Kal and Source Naturals vitamins at inexpensive prices.
*Statements contained herein have not been evaluated by the Food and Drug Administration. Carnosine is not intended to diagnose, treat and cure or prevent disease. Always consult with your professional health care provider before changing any medication or adding Vitamins to medications.