Background: Obese patients are frequently characterized by insulin resistance and decreased insulin-mediated glycogen synthesis in skeletal muscle. Whether they also have impaired postprandial hepatic glycogen synthesis remains unknown.
Aim: To determine whether postprandial hepatic glycogen synthesis is decreased in obese patients compared to lean subjects.
Methods: Lean and obese subjects with impaired glucose tolerance were studied over 4h after ingestion of a glucose load. Hepatic uridine diphosphoglucose kinetics were assessed using 13C-galactose infusion, with monitoring of urinary acetaminophen-glucuronide isotopic enrichment to estimate hepatic glycogen kinetics.
Results: Estimated net hepatic glycogen synthesis amounted to 18.6 and 22.6% of the ingested load in lean and obese subjects, respectively.
Conclusion: Postprandial hepatic glycogen metabolism is not impaired in non-diabetic obese subjects.