Upregulation of mammary gland OCTNs maintains carnitine homeostasis in suckling infants.

Background: Transport of L-carnitine, essential cofactor of fatty acid metabolism, into breast milk is critical for the normal growth and development of the suckling infant.

Objective: To increase understanding of developmental expression of carnitine/organic cation (Octn) transporter family at different stages of murine breast development for carnitine delivery.

Methods: We applied our transporter-specific antibodies to mOctn1, mOctn2 and mOctn3 to sections of mammary glands of virginal non-lactating, pregnant, late lactating and post-lactating C3H females.

Epitope shared by functional variant of organic cation/carnitine transporter, OCTN1, Campylobacter jejuni and Mycobacterium paratuberculosis may underlie susceptibility to Crohn's disease at 5q31.

Campylobacter jejuni and Mycobacterium paratuberculosis have been implicated in the pathogenesis of Crohn's disease. The presence of bacterial metabolites in the colonic lumen causing a specific breakdown of fatty acid oxidation in colonic epithelial cells has been suggested as an initiating event in inflammatory bowel disease (IBD). l-Carnitine is a small highly polar zwitterion that plays an essential role in fatty acid oxidation and ATP generation in intestinal bioenergetic metabolism.