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Related Experiment Video

Updated: Jul 12, 2026

Identifying Amino Acid Overproducers Using Rare-Codon-Rich Markers

Identifying Amino Acid Overproducers Using Rare-Codon-Rich Markers

Published on: June 24, 2019

Leucing weight with a futile cycle.

Susan K Fried¹, Malcolm Watford

¹Division of Endocrinology, Diabetes and Nutrition, Department of Medicine and GRECC, Baltimore VA Medical Center, Baltimore, MD 21201, USA. sfried@medicine.umaryland.edu

Cell Metabolism

|September 5, 2007

Summary

Raising leucine levels by blocking its breakdown creates a futile cycle, increasing energy expenditure and improving obesity resistance and insulin sensitivity.

Area of Science:

Biochemistry
Metabolic pathways
Amino acid signaling

Background:

Leucine is an essential amino acid crucial for activating protein synthesis.
The role of leucine metabolism in energy balance and metabolic health is under investigation.

Discussion:

Blocking leucine breakdown leads to elevated circulating leucine levels.
This elevation induces a futile cycle of protein synthesis and degradation.
This cycle results in increased energy expenditure.

Key Insights:

Elevated leucine promotes resistance to dietary obesity.
Improved insulin sensitivity is observed with increased leucine signaling.
Leucine metabolism directly impacts whole-body energy homeostasis.

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Published on: January 26, 2012

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Metabolic Labeling of Leucine Rich Repeat Kinases 1 and 2 with Radioactive Phosphate

Published on: September 18, 2013

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Last Updated: Jul 12, 2026

Identifying Amino Acid Overproducers Using Rare-Codon-Rich Markers

Identifying Amino Acid Overproducers Using Rare-Codon-Rich Markers

Published on: June 24, 2019

Metabolic Pathway Confirmation and Discovery Through 13C-labeling of Proteinogenic Amino Acids

Metabolic Pathway Confirmation and Discovery Through ¹³C-labeling of Proteinogenic Amino Acids

Published on: January 26, 2012

Metabolic Labeling of Leucine Rich Repeat Kinases 1 and 2 with Radioactive Phosphate

Metabolic Labeling of Leucine Rich Repeat Kinases 1 and 2 with Radioactive Phosphate

Published on: September 18, 2013

Outlook:

Further research into modulating leucine metabolism for metabolic disease treatment.
Exploring therapeutic strategies targeting protein synthesis and degradation pathways.
Investigating the long-term effects of sustained elevated leucine levels.