Carnosine in exercise and disease: introduction

In the historical city center of Ghent in Belgium, an international group of scientists gathered for a 3-day meeting dedicated to carnosine research. The meeting took place in July 2011, which is more than 10 years following the previous congress of this kind, organized by Alexander Boldyrev in Moscow in the year 2000. The Moscow meeting was held on the occasion of the centenary of Gulewitch and Amiradzhibi’s discovery of the dipeptide carnosine in meat extract. A special issue with contributions from the invited participants was published in Biochemistry (Moscow) in 2000, entitled: ‘‘Biological role of carnosine in the functioning of excitable tissues’’ (Guest editor: A. A. Boldyrev; Original Russian text). The Ghent meeting was therefore considered the Second International Meeting on Carnosine. The souvenir medals that were created to mark the occasion of both meetings are displayed in Fig. 1. A thorough understanding of the biological role of carnosine and its methylated analogues anserine and ophidine/ balenine, is still hampered by the relatively low frequency of scientific discoveries on this topic. However, in the 11-year period separating both meetings there has been an exponential increase in the number of publications and citations on carnosine (see Fig. 2). Indeed, significant progress was made in the fields of both biochemistry and medicine, as well as in sport science. The genes for carnosine synthase and carnosinase, the principal enzymes responsible for carnosine synthesis and degradation, were molecularly identified and cloned in 2003 and 2010, respectively. A polymorphism in the gene for the carnosine-degrading enzyme carnosinase was defined as an important genetic risk factor for diabetic nephropathy. The evidence for a therapeutic role of carnosine in aging and neurologic diseases has expanded and new target diseases, such as diabetes/metabolic syndrome, liver and kidney disease and cancer, have been successfully explored in animal experiments. Carnosinase-resistant analogues of carnosine are developed in the pharmaceutical industry for increased therapeutic potential and stability. Finally, the content of muscle carnosine appears to influence athletic performance and can be augmented by oral beta-alanine supplementation, making beta-alanine increasingly popular in the athletic community. Thus, a new meeting was timely and needed. The current special issue in Amino Acids provides a selection of contributions presented at the Ghent meeting, containing original papers, review articles and a new perspective. Carnosine was originally discovered in skeletal muscle, where it has a far greater concentration compared to all other tissues. The regulation of the carnosine content in muscle is still incompletely understood, but the current knowledge is elegantly summarized in this special issue by Harris et al. (2012, this issue). A recent development of a non-invasive magnetic resonance spectroscopy (MRS) based method to quantify muscle carnosine in humans has further facilitated the research on this topic. Accordingly, a study based on over 260 male and female healthy humans aged 9–83 years (Baguet et al. 2012, this issue) indicates This is the introduction paper to the Special Issue of Amino Acids, entitled ‘Carnosine in Exercise and Disease’ and edited by Craig Sale and Wim Derave.