title: Effect of L-carnitine supplementation on secondary hyperparathyroidism and bone metabolism in hemodialyzed patients.
abstract: The aim of our work was to test the influence of L-carnitine supplementation on secondary hyperparathyroidism and bone metabolism in hemodialyzed patients in a randomized study. Eighty-three chronically hemodialyzed patients were observed; 44 were supplemented with L-carnitine (15 mg/kg intravenously after each hemodialysis for 6 months), while 39 took placebo. Levels of free carnitine (CAR), calcium (Ca), inorganic phosphate (P), Ca x P product, parathormone (PTH), bone-specific alkaline phosphatase (b-ALP), osteocalcin (OC), and osteoprotegerin (OPG) were monitored. In comparison with pretreatment values, changes of some selected parameters occurred in the supplemented patients after 6 months (data are expressed as medians; NS, nonsignificant change): PTH, 186.0 vs. 135.5 ng/L (NS); b-ALP, 13.9 vs. 13.2 microg/L (P < 0.05); OC, 78.3 vs. 68.8 microg/L (NS); OPG, 144.0 vs. 182.0 ng/L (P < 0.05). In the controls, there were the following changes: PTH, 148.0 vs. 207.0 ng/L (NS); b-ALP, 15.2 vs. 13.2 microg/L (P < 0.05); OC, 62.7 vs. 79.8 microg/L (P < 0.05); OPG, 140.0 vs. 164.0 ng/L (NS). A significant correlation was found between CAR and OPG changes (r = 0.51, P < 0.001) in the supplemented patients. The supplementation led to a significant increase of serum OPG concentration. Nevertheless, we observed only nonsignificant tendencies to correction of secondary hyperparathyroidism and reduction of bone turnover in hemodialyzed patients supplemented with L-carnitine in contrast to controls. At this point, the use of L-carnitine does not seem to be justified.
authors.affiliation: Institute of Clinical Biochemistry and Hematology, Charles University Medical Faculty and Faculty Hospital, Alej Svobody 80, CZ-304 60, Pilsen, Czech Republic. cibulkar@fnplzen.cz
authors.forename: Roman
authors.initials: R
authors.lastname: Cibulka
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Racek
authors.forename: Richard
authors.initials: R
authors.lastname: Pikner
authors.forename: Daniel
authors.initials: D
authors.lastname: Rajdl
authors.forename: Ladislav
authors.initials: L
authors.lastname: Trefil
authors.forename: Eugenie
authors.initials: E
authors.lastname: Vesela
authors.forename: Marie
authors.initials: M
authors.lastname: Studenovska
authors.forename: Romana
authors.initials: R
authors.lastname: Siroka
mesh_terms: D000368:Aged; D015519:Bone Density / Q000187:drug effects* / Q000502:physiology; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D002118:Calcium / Q000097:blood; D002331:Carnitine / Q000008:administration & dosage / Q000494:pharmacology*; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood / Q000187:drug effects; D010024:Osteoporosis / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology; D053244:Osteoprotegerin / Q000097:blood / Q000187:drug effects; D010710:Phosphates / Q000097:blood; D006435:Renal Dialysis / Q000009:adverse effects*; D051437:Renal Insufficiency / Q000628:therapy; D016896:Treatment Outcome; D015854:Up-Regulation / Q000502:physiology
chemical_list: D053244:Osteoprotegerin; D010710:Phosphates; D015675:Osteocalcin; D002331:Carnitine; D002118:Calcium