Carnitine Enigma: From Antioxidant Action to Vitagene Regulation. Part 1. Absorption, Metabolism, and Antioxidant Activities

L-carnitine (LC) is a small water-soluble molecule playing an important role in fat metabolism and there is a growing interest in the potential uses of LC as a medicinal agent and as a nutritional/dietary supplement. In addition to a great interest from medical sciences, carnitine received a substantial attention from pig and poultry industry. In particular, poultry and pig diets are formulated mainly with plant feed ingredients which are poor sources of carnitine. Furthermore, internal carnitine synthesis depends on many factors and in some cases could be inadequate. Therefore, it seems likely that carnitine dietary supplementation of highly productive and/or stressed animals/birds is of great importance. The molecular mechanisms accounting for the positive effects of LC on farm animals and poultry are not yet determined but many protective effects of LC reported in literature have been related to its antioxidant action.