Serum free-carnitine levels were determined in 973 unrelated white collar workers in Akita, Japan. Fourteen of these participants consistently had serum free-carnitine levels below the fifth percentile (28 microM for females and 38 microM for males). The OCTN2 (organic cation transporter) gene was sequenced for these 14 subjects, for 22 subjects whose carnitine levels were below the fifth perce...

Fat and carbohydrate are the primary fuel sources for mitochondrial ATP production in human skeletal muscle during endurance exercise. However, fat exhibits a relatively low maximal rate of oxidation in vivo, which begins to decline at around 65% of maximal oxygen consumption (VO2max) when muscle glycogen becomes the major fuel. It is thought that if the rate of fat oxidation during endurance e...

Acetylation of added (-)carnitine by heart mitochondira coupled to the oxidation of pyruvate in the presence of malonate was inhibited, apparently competitively, by long chain acyl(+)carnitines although the activity of carnitine acetyltransferase (EC 2.3.1.7) itself was not affected. Mitochondria have been found to possess a translocase system that allows the transport of carnitine and acylcarn...

L‐carnitine (free carnitine) transports cytosolic long‐chain fatty acids as acylcarnitines across the inner mitochondrial membrane for β‐oxidation and subsequent ATP production in the mitochondria. The endogenous carnitine pool comprises free L-carnitine as well as short-, mediumand long-chain fatty acid esters (acyl-carnitines) and depends on absorption of L-carnitine from dietary sources, end...

L-carnitine and acetyl-L-carnitine (ALC) are both used to improve mitochondrial function. Although it has been argued that ALC is better than l-carnitine in absorption and activity, there has been no experiment to compare the two compounds at the same dose. In the present experiment, the effects of ALC and L-carnitine on the levels of free, acyl, and total L-carnitine in plasma and brain, rat a...

The main objective for the present research is to assess effect of cyclic starvation and L- carnitine supplementation on growth (body final weight, hepatosomatic index (HSI), daily growth rate (DGI), feed conversion ratio (FCR) and voluntary feed intake (VFI)), body compositions (crude protein, crude lipid, ash and moisture), biochemical (plasma total protein, glucose, cholesterol, triglyceride...

Diabetes, starvation and various hormonal treatments are known to alter drastically carnitine concentrations in the body. Before the mechanisms controlling carnitine metabolism could be determined, it was necessary to establish normal carnitine concentrations in both sexes at different ages. Carnitine was assayed in plasma, liver, heart and skeletal muscle of rats from birth to weaning. The pla...

Carnitine is a small molecule widely present in all cells from prokaryotic to eukaryotic. It is an important element in β-oxidation of fatty acids. Carnitine is a scavenger of oxygen free radicals in mammalian tissues. Lack of carnitine in a hemodialysis patient can lead to carnitine deficiency. Oxidation of fatty acids and lipid metabolism are severly affected by carnitine deficiency. Oxidativ...

The therapeutic effect of L-carnitine on arrhythmias during hemodialysis was evaluated in 17 patients with chronic renal disease undergoing intermittent hemodialysis. In 11 of 17 patients (65%), ventricular or supraventricular premature beats appeared at 20 to 30 min after the start of hemodialysis and continued throughout the dialysis. Plasma carnitine was at a lower level in the predialysis p...

BACKGROUND Long-term treatment with antibiotics containing pivalic acid may decrease serum carnitine concentration and can sometimes be associated with severe hypoglycemia and encephalopathy in infants. Little has been reported, however, on severe hypocarnitinemia induced by acute administration in older children. CASE PRESENTATION We describe a 6-year-old Japanese girl with Fukuyama-type con...