Glycine and L-carnitine therapy in 3-methylcrotonyl-CoA carboxylase deficiency.

Journal Article (Journal Article)

Genetic deficiency of 3-methylcrotonyl-CoA carboxylase (3-MCC) is a rare inborn error of leucine metabolism producing an organic acidaemia. With accumulation of 3-methylcrotonyl-CoA, there is increased production of 3-hydroxyisovaleric acid, the glycine conjugate (3-methylcrotonylglycine), and the carnitine conjugate (3-hydroxyisovalerylcarnitine). The conjugates represent endogenous detoxification products. We studied excretion rates of these conjugates at baseline and with glycine and carnitine therapy in an 8-year-old girl with 3-MCC deficiency. Her preadmission diet was continued. Plasma and urine samples were obtained after 24 h of each of the following: L-carnitine 100 mg/kg per day and glycine 100, 175 and 250 mg/kg per day. Plasma and urinary carnitine levels were reduced by 80% and 50%, respectively with abnormal urinary excretion patterns. These normalized with carnitine therapy. Acylcarnitine excretion increased with carnitine therapy. The glycine conjugate, 3-methylcrotonylglycine (3-MCG), was the major metabolite excreted at all times and its excretion increased with glycine therapy. Clearly, in 3-MCC deficiency the available glycine and carnitine pools are not sufficient to meet the potential for conjugation of accumulated metabolites, suggesting a possible therapeutic role for glycine and carnitine therapy in this disorder.

Full Text

Duke Authors

Cited Authors

  • Rutledge, SL; Berry, GT; Stanley, CA; van Hove, JL; Millington, D

Published Date

  • 1995

Published In

Volume / Issue

  • 18 / 3

Start / End Page

  • 299 - 305

PubMed ID

  • 7474896

International Standard Serial Number (ISSN)

  • 0141-8955

Digital Object Identifier (DOI)

  • 10.1007/BF00710419


  • eng

Conference Location

  • United States