Decreased glucose oxidation during short-term starvation.
Prolonged fasting (for days or weeks) decreases glucose production and oxidation. The effects of short-term starvation (ie, less than 24 hours) on glucose metabolism are not known. To evaluate this issue, glucose oxidation and glucose turnover were measured after 16-hour and subsequently after 22-hour fasting. Glucose oxidation was calculated by indirect calorimetry in 12 healthy men (age 22 to 44 years); glucose turnover was measured by primed, continuous infusion of 3-3H-glucose in eight of these 12 volunteers. After 16-hour fasting net glucose oxidation was 0.59 +/- 0.17 mg x kg-1 x min-1 and glucose tissue uptake 2.34 +/- 0.12 mg x kg-1 x min-1. No correlation was found between net glucose oxidation and glucose tissue uptake. Prolonging fasting with an additional 6 hours resulted in decreases of respiratory quotient (0.77 +/- 0.01 v 0.72 +/- 0.01) (P less than .005), plasma glucose concentration (4.7 +/- 0.1 v 4.6 +/- 0.1 mmol/L) (P less than .05), glucose tissue uptake (2.10 +/- 0.12 mg x kg-1 x min-1) (P less than .05), net glucose oxidation (0.09 +/- 0.04 mg x kg-1 x min-1) (P less than .005), and plasma insulin concentration (8 +/- 1 v6 +/- 1 mU/L) (P less than .005). Net glucose oxidation expressed as a percentage of glucose tissue uptake decreased from 22% +/- 8% to 2% +/- 1% (P less than .05). There was no net glucose oxidation in seven of 12 controls after 22-hour fasting.(ABSTRACT TRUNCATED AT 250 WORDS)
Romijn
J A
JA
Department of Intensive Care, University of Amsterdam, The Netherlands.
Godfried
M H
MH
Hommes
M J
MJ
Endert
E
E
Sauerwein
H P
HP
D000328:Adult; D002151:Calorimetry; D002245:Carbon Dioxide / Q000502:physiology; D005215:Fasting; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D005947:Glucose / Q000378:metabolism* / Q000493:pharmacokinetics; D006801:Humans; D007657:Ketone Bodies / Q000378:metabolism; D050356:Lipid Metabolism; D008297:Male; D010084:Oxidation-Reduction; D013217:Starvation / Q000378:metabolism*; D013997:Time Factors
D005230:Fatty Acids, Nonesterified; D007657:Ketone Bodies; D002245:Carbon Dioxide; D005947:Glucose