Carnitine organic cation transport

Lahjouji, K., G. A. Mitchell, and I. A. Qureshi. Carnitine transport by organic cation transporters and systemic carnitine deficiency. Mol. Genet. Metab. 2001, 73, 287-297. 

Ohashi, R., et al. Na(+)-dependent carnitine transport by organic cation transporter (OCTN2) its pharmacological and toxicological relevance. J. Pharmacol. Exp. Ther. 1999, 292, 778-784. 

Rytting E and Audus KL (2005) Novel organic cation transporter 2-mediated carnitine uptake in placental choriocarcinoma (BeWo) cells. J Pharmacol Exp Ther 312(1) 192—198. 

Seth P, Wu X, Huang W, Leibach FH, Ganapathy V. Mutations in novel organic cation transporter (OCTN2), an organic cation/carnitine transporter, with differential effects on the organization transport function and the carnitine transport function. J Biol Chem 1999 274 33388-33392. 

SNPs were identified in the Japanese population for the organic cation transporter 1 (OCTI), and when functionally characterized in vitro, the uptake of cations was reduced significantly for some of these mutations, indicating that this would likely contribute to interindividual variations in metabolism of drugs that are transported via OCTI [13]. The sodium-dependent carnitine cotransporter OCTN2 can also possess mutations that result in primary carnitine deficiency, thus impacting fatty acid oxidation that is characterized by many clinical manifestations [14]. 

OAT/OCT Most solute transporters, including the members of the 5LC22-family, share a predicted membrane topology with 12 transmembrane domains. This family comprises organic cation transporters (OCTs), as well as transporters for the zwitterion carnitine (OGTNs) and organic anion transporters (OATs). 

Koch, A., B. Kbnig, G.l. Stangl, and K. Eder. 2008. PPARa mediates transcriptional upregu-lation of novel organic cation transporters-2 and -3 and enzymes involved in hepatic carnitine synthesis. Experimental Biology and Medicine (Maywood) 233 356-65. 

S., F. Hirche, and K. Eder. 2008. Fasting and caloric restriction increases mRNA concentrations of novel organic cation transporter-2 and carnitine concentrations in rat tissues. Armais of Nutrition and Metabolism 52 58-67. 

Once carnitine is produced, the intracellular homeostasis is controlled by different membrane transporters called organic cation transporters (OCTNs), specifically OCTN2. OCTN2 acts to operate on both the intestinal and renal absorption of L-camitine, in addition to playing a major role in tissue distribution and transport rates within circulation. This transporter has been implieated in the deficiencies mentioned earlier in this chapter, as research has shown that OCTN2 is directly inhibited by various agents and substances identified as eausing systemic carnitine deficiencies. ... 

Wang Y, Ye J, Ganapathy V, Longo N. Mutations in the organic cation/camitine transporter OCTN2 in primary carnitine deficiency. Proc Natl Acad Sci USA 1999 96(5) 2356-2360. 

Ganapathy ME, Huang W, Raj an DP, Carter AL, Sugawara M, Iseki K et al. /1-lactam antibiotics as substrates for OCTN2, an organic cation/carnitine transporter. J Biol Chem 2000 275(3) 1699 1707. 

Tang NL, Ganapathy V, Wu X, Hui J, Seth P, Yuen PM et al. Mutations of OCTN2, an organic cation/carnitine transporter, lead to deficient cellular carnitine uptake in primary carnitine deficiency. Hum Mol Genet 1999 8(4) 655-660. 

Y. Kato, M. Sugiura, T. Sugiura, T. Wakayama, Y. Kubo, D. Kobayashi, Y. Sai, I. Tamai, S. Iseki, and A. Tsuji. Organic cation/camitine transporter octn2 (slc22a5) is responsible for carnitine transport across apical membranes of small intestinal epithelial cells in mouse. Mol Pharmacol 70 829-837 (2006). 

OCTN organic cation/carnitine transporter PSS progressive systemic sclerosis... 

Wang, Y., Ye, J., Ganapafhy, V. and Longo, N. (1999) Mutations in the organic cation/ carnitine transporter OCTN2 in, primary carnitine deficiency. Proceedings of the National Academy of Sciences of the United States of America, 96 (5), 2356-2360. 

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