Short-term infusion of azelaic acid vs intralipid in healthy subjects evaluated by indirect calorimetry

Medium-chain dicarboxylic acids (MCDA) are usually considered byproducts of beta-oxidation when omega-oxidizable medium-chain monocarboxylic acids are accumulated, as in beta-oxidation impairment. However, evidence exists of a mitochondrial and cytoplasmatic peroxisomal carnitine independent beta-oxidation of these diacids. Our purpose was to evaluate whether MCDA could be used as source of calories. The metabolic response to intravenous administration of azelaic acid (AA) vs Intralipid (IL) was evaluated in six healthy overnight fasting male volunteers who received an infusion of 10 g of AA over 80 min and as a control 10 g of IL. AA reached a peak concentration at 80 min, (589 +/- 61 micrograms/ml) and was rapidly cleared from plasma (82 +/- 5 micrograms/ml at 240 min). Respiratory and metabolic parameters were evaluated by indirect calorimetry from the beginning of the infusion for 240 min. In both groups the CO2 production (VCO2) remained unchanged with no significant change from basal values. The O2 consumption (VO2 ml/min/m2) increased over basal values reaching a peak at the end of the infusion in both groups (AA from 119.4 +/- 16.9 to 143.0 +/- 27.6; IL from 124.7 +/- 16.8 to 152.3 +/- 29.5). Respiratory quotient (RQ) consequently decreased significantly (AA from 0.85 +/- 0.06 to 0.76 +/- 0.06; IL from 0.89 +/- 0.06 to 0.78 +/- 0.03) and calories derived from lipids increased. Metabolic rate (MR kcal/hr/m2) showed a slight increase (AA from 34.0 +/- 4.4 to 40.3 +/- 6.8; IL from 35.9 +/- 5.1 to 41.3 +/- 10.5). There was no significant difference between AA and IL treatment in all measurements.(ABSTRACT TRUNCATED AT 250 WORDS)