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Updated: Jul 17, 2026
12:11
Determination of Fatty Acid Oxidation and Lipogenesis in Mouse Primary Hepatocytes
Published on: August 27, 2015
Hepatic ketogenesis and gluconeogenesis in humans
The Journal of Clinical Investigation
|October 1, 1974
Summary
After 3 days of starvation, hepatic ketogenesis equals ketone body production, suggesting peripheral ketone removal is key to prolonged starvation hyperketonemia. Gluconeogenesis also increases, showing a direct link between these metabolic pathways.
Area of Science:
- Metabolic research
- Human physiology
- Clinical nutrition
Background:
- Understanding substrate metabolism during starvation is crucial for metabolic disease research.
- Previous studies have focused on prolonged starvation, leaving a gap in knowledge for short-term starvation.
- Splanchnic substrate exchange and hepatic blood flow are key indicators of metabolic adaptation.
Purpose of the Study:
- To investigate splanchnic arterio-hepatic venous differences in carbohydrate and lipid metabolism after 3 days of starvation.
- To simultaneously measure hepatic blood flow and substrate exchange.
- To compare these metabolic rates with those observed in overnight fasting and prolonged starvation.
Main Methods:
- Measurement of splanchnic arterio-hepatic venous differences for various substrates.
- Simultaneous determination of hepatic blood flow.
- Analysis of carbohydrate and lipid metabolism markers in five post-absorptive patients.
Main Results:
- Splanchnic production of beta-hydroxybutyrate and acetoacetate were equal, totaling 115 g/24 h, matching rates seen in prolonged starvation.
- Hepatic glucose release was 123 g/24 h, lower than overnight fasting but higher than prolonged starvation.
- Hepatic gluconeogenesis was estimated at 99 g/24 h, exceeding rates in both overnight and prolonged starvation.
- A direct relationship was observed between hepatic ketogenesis and gluconeogenesis.
Conclusions:
- Peripheral ketone body removal significantly impacts hyperketonemia during prolonged starvation.
- Short-term starvation (3 days) shows elevated hepatic gluconeogenesis compared to overnight or prolonged fasting.
- Ketogenesis and gluconeogenesis are directly interrelated during short-term starvation.
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