EXCRETION OF C6-C10 DICARBOXYLIC ACIDS IN THE URINE OF NEWBORN-INFANTS DURING STARVATION - EVIDENCE FOR OMEGA-OXIDATION OF FATTY-ACIDS IN THE NEWBORN

ABSTRACT. Gregersen, N. and Ingerslev, J. (Research Laboratory for Metabolic Disorders, University Department of Clinical Chemistry and University Department of Obstetrics and Gynaecology, Aarhus kommunehospital, Aarhus, Denmark). The excretion of C6–C10‐dicarboxylic acids in the urine of newborn infants during starvation. Acta Paediatr Scand, 68: 677, 1979.—The excretion of C6–C10‐dicarboxylic acids, i.e. adipic, suberic and sebacic acids, was measured during the three first days of life in 3 fasting newborns, 2 newborns fed with isocaloric glucose and 2 newborns given mothers'‐milk. On the second and third day of life the starved children excreted 27–84 mmol adipic acid/mol creatinine, 6–22 mmol suberic acid/mol creatinine and 4–7 mmol sebacic acid/mol creatinine. The excretion of C6–C10‐dicarboxylic acids in the neonates given glucose or mothers'‐milk was, for the first three days of life, 0–9 mmol adipic acid/mol creatinine, 0–10 mmol suberic acid/mol creatinine and 0–4 mmol sebacic acid/mol creatinine. The latter amounts are equivalent to the excretion of dicarboxylic acids in older children. It is argued that the detected dicarboxylic acids are formed by ω‐oxidation of long‐chain monocarboxylic acids followed by β‐oxidation, and that the excreted amounts reflect ω‐oxidation activity. It is speculated that the substantial ω‐oxidation activity in the starving newborn serve to provide succinyl‐CoA‐substrate for the citric acid cycle and for gluconeogenesis. Copyright © 1979, Wiley Blackwell. All rights reserved