Carnitine deficiency induced during hemodialysis and hyperlipidemia: effect of replacement therapy

Abstract

Plasma carnitine levels were studied in 14 uremic patients before, during, and after hemodialysis. The predialysis plasma carnitine levels were normal but fell during dialysis (half-life of 3.6 h). Plasma carnitine levels rose quickly in the first 6 h after dialysis, after which time the rise was more gradual. Muscle carnitine was significantly reduced in the dialyzed patients (p less than 0.005) compared with controls. In four patients lipid droplets were observed in muscle. Ten patients on maintenance hemodialysis exhibited plasma hyperlipidemia and low muscle carnitine. These individuals were given DL-carnitine (50 mg/kg body weight) intravenously after each dialysis. At the end of a 2-month carnitine treatment, plasma triglyceride levels were found to be reduced (p less than 0.001) and muscle carnitine content significantly increased (p less than 0.005). These findings suggest that carnitine may be useful in treatment of hypertriglyceridemia and muscle carnitine deficiency states induced during maintenance hemodialysis.

Effect of <i>L</i>-Carnitine Supplementation on Lipid Parameters in Hemodialysis Patients

“…These results are in agreement with some previously published data in the literature [11][12][13][14][15][16][17][18][19][20]. Even though the time-dependent change in serum triglycerides cannot be securely excluded in some of the patients, this decrease should be due to the carnitine-induced stimulation of the oxidation of long-chain fatty acids, which in turn leads to a decrease of their availability for esterification to triglycerides [9,10].…”

“…Carnitine, which is considered to be essential for the transport of fatty acids from the cytosol into the mitochondria, where they are oxidized, seems to play an important role in lipid catabolism [9,10]. However, the results of studies in which L-carnitine has been administered in hemodialysis patients in an attempt to correct the lipid abnormalities are inconclusive, with some studies noting an improvement [11][12][13][14][15][16][17][18][19][20], while others found no change or even an exacerbation of hypertriglyceridemia [14,[20][21][22][23][24][25][26][27][28]. Some of the observed discrepancies might be attributed to differences in racial or ethnic background, cultural factors, diets or to differences in the criteria for selection of the study participants.…”

Serum Free Carnitine, Carnitine Esters and Lipids in Patients on Peritoneal Dialysis and Hemodialysis

“…On the other hand, several authors observed predialysis plasma carnitine levels in patients on HD which are not different from the mean of normal controls [14][15][16][17][18] or even significantly elevated [19. 20].…”

“…Marked depletion of blood carnitine has been reported during HD [2. [13][14][15][17][18][19][20][21][22][23], TC decreased from 48.2 ± 18.8 to 20.9 ± 9.0, FC from 29.6 ± 12.6 to 9.4 ± 5.6. SCC from 17.7 ± 8.9 to 9.5 ± 5.6 and LCC from 2.5 ± 1.2 to 1.6 ± 0.9 pmol/l [21].…”

Muscle Metabolism in Uremia and the Effect of Amino Acid Supplementation

“…Their uptake into the mitochondria is mediated by the quaternary amine carnitine. Some [39] but not all investigators report low plasma free carnitine in maintenance hemodialyzed patients [40, 41]. Moreover, a deficit in L -carnitine is responsible for atrophy of type I and IIA muscle fibers and is associated with an accumulation of intracytoplasmatic lipids which is not seen in muscular atrophy of the uremic patient [24, 42].…”