Plasma acetone metabolism in the fasting human

J Clin Invest. 1979 Apr;63(4):619-26. doi: 10.1172/JCI109344.

Abstract

The metabolism of acetone was studied in lean and obese humans during starvation ketosis. Acetone concentrations in plasma, urine, and breath; and rates of endogenous production, elimination in breath and urine, and in vivo metabolism were determined. There was a direct relationship between plasma acetone turnover (20-77 mumol/m(2) per min) and concentration (0.19-1.68 mM). Breath and urinary excretion of acetone accounted for a 2-30% of the endogenous production rate, and in vivo metabolism accounted for the remainder. Plasma acetone oxidation accounted for congruent with60% of the production rate in 3-d fasted subjects and about 25% of the production rate in 21-d fasted subjects. About 1-2% of the total CO(2) production was derived from plasma acetone oxidation and was not related to the plasma concentration or production rate. Radioactivity from [(14)C]acetone was not detected in plasma free fatty acids, acetoacetate, beta-hydroxybutyrate, or other anionic compounds, but was present in plasma glucose, lipids, and proteins. If glucose synthesis from acetone is possible in humans, this process could account for 11% of the glucose production rate and 59% of the acetone production rate in 21-d fasted subjects. During maximum acetonemia, acetone production from acetoacetate could account for 37% of the anticipated acetoacetate production, which implies that a significant fraction of the latter compound does not undergo immediate terminal oxidation.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acetone / blood*
  • Acetone / urine
  • Adult
  • Blood Glucose / metabolism
  • Carbon Dioxide
  • Fasting*
  • Female
  • Humans
  • Ketone Bodies / blood
  • Kinetics
  • Male
  • Middle Aged
  • Obesity / metabolism

Substances

  • Blood Glucose
  • Ketone Bodies
  • Acetone
  • Carbon Dioxide