Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Fats as Energy Storage Molecules01:06

Fats as Energy Storage Molecules

26.6K
Triglycerides are a form of long-term energy storage molecules. They are made of glycerol and three fatty acids. To obtain energy from fat, triglycerides must first be broken down by hydrolysis into their two principal components, fatty acids and glycerol. This process, called lipolysis, takes place in the cytoplasm. The resulting fatty acids are oxidized by β-oxidation into acetyl-CoA, which is used by the Krebs cycle. The glycerol that is released from triglycerides after lipolysis...
26.6K
Overview of Fatty Acid Metabolism01:28

Overview of Fatty Acid Metabolism

35.7K
Lipids also are sources of energy that power cellular processes. Like carbohydrates, lipids are composed of carbon, hydrogen, and oxygen, but these atoms are arranged differently. Most lipids are nonpolar and hydrophobic. Major types include fats and oils, waxes, phospholipids, and steroids.
Fatty acids are catabolized in a process called beta-oxidation, which takes place in the matrix of the mitochondria and converts their fatty acid chains into two-carbon units of acetyl groups. The acetyl...
35.7K
Metabolic States of the Body: Fasting and Starvation01:24

Metabolic States of the Body: Fasting and Starvation

2.5K
During the initial hours of fasting, the body uses up its glycogen stores as an energy source. Once these glycogen reserves are depleted, the body begins breaking down stored triglycerides and structural proteins. During this stage, glycerol becomes a key substrate for gluconeogenesis, while free fatty acids undergo beta-oxidation to provide energy for tissues, such as skeletal muscle. In the fasting state, the body spares protein breakdown as much as possible to conserve muscle and structural...
2.5K
Lipid Catabolism01:25

Lipid Catabolism

676
Triglycerides serve as crucial long-term energy storage molecules in microorganisms, providing a dense source of metabolic energy. Their breakdown is mediated by lipases, which hydrolyze triglycerides into glycerol and free fatty acids. Each of these components follows distinct metabolic pathways, ultimately contributing to ATP synthesis and cellular energy homeostasis.Glycerol MetabolismGlycerol, released from triglyceride hydrolysis, is phosphorylated by glycerol kinase to form...
676
Overview of Lipid Metabolism01:24

Overview of Lipid Metabolism

4.3K
Lipid metabolism is a crucial process in the human body that involves the synthesis and degradation of lipids. This process is essential for energy production, cell membrane formation, and hormone production, among other functions.
Lipolysis: The Breakdown of Lipids:
Lipolysis is the process of breaking down lipids, particularly triglycerides, into glycerol and fatty acids. This process typically occurs in the adipose tissue and is triggered by various hormones, including glucagon and...
4.3K
Dietary Connections01:23

Dietary Connections

61.1K
In biological systems, most metabolic pathways are interconnected. The cellular respiration processes that convert glucose to ATP—such as glycolysis, pyruvate oxidation, and the citric acid cycle—tie into those that break down other organic compounds. As a result, various foods—from apples to cheese to guacamole—end up as ATP. In addition to carbohydrates, food also contains proteins and lipids—such as cholesterol and fats. All of these organic compounds are used...
61.1K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Use of Compartmental Modeling to Study Long-Term Adaptation to Increases or Decreases in Daily Vitamin A Intake in Theoretical Women.

The Journal of nutrition·2026
Same author

Development and Initial Validation of a Simplified Approach for Compartmental Modeling of Vitamin A Kinetics in Theoretical and Real Human Subjects.

The Journal of nutrition·2026
Same author

Estimating Vitamin A Absorption Using Compartmental Modeling of Plasma Retinyl Ester Kinetics in Humans.

The Journal of nutrition·2025
Same author

A Restated and More Straightforward Retinol Isotope Dilution Equation for Predicting Vitamin A Total Body Stores.

The Journal of nutrition·2025
Same author

A Method That Maintains Accuracy in the Prediction of Vitamin A Total Body Stores When Population-Based Modeling of a Limited Number of Theoretical Subjects Is Used With Retinol Isotope Dilution.

The Journal of nutrition·2025
Same author

Use of Population-Based Compartmental Modeling and Retinol Isotope Dilution to Study Vitamin A Kinetics and Total Body Stores among Ghanaian Women of Reproductive Age.

Current developments in nutrition·2024

Related Experiment Video

Updated: Dec 15, 2025

Quantitative Determination of De Novo Fatty Acid Synthesis in Brown Adipose Tissue Using Deuterium Oxide
07:34

Quantitative Determination of De Novo Fatty Acid Synthesis in Brown Adipose Tissue Using Deuterium Oxide

Published on: May 12, 2023

1.4K

Are Fatty Acids Gluconeogenic Precursors?

Michael H Green1

  • 1Department of Nutritional Sciences, College of Health and Human Development, The Pennsylvania State University, University Park, PA, USA.

The Journal of Nutrition
|July 12, 2020
PubMed
Summary

Fatty acids are a source of glucose, challenging textbook omissions. Carbon from fatty acid oxidation enters the tricarboxylic acid cycle and contributes to glucose production via gluconeogenesis.

Keywords:
TCA cyclefatty acidsgluconeogenesisgluconeogenic precursorsnet gainprecursortracer studies

More Related Videos

Liquid Chromatography Coupled to Refractive Index or Mass Spectrometric Detection for Metabolite Profiling in Lysate-based Cell-free Systems
14:42

Liquid Chromatography Coupled to Refractive Index or Mass Spectrometric Detection for Metabolite Profiling in Lysate-based Cell-free Systems

Published on: September 23, 2021

5.5K
Determination of Fatty Acid Oxidation and Lipogenesis in Mouse Primary Hepatocytes
12:11

Determination of Fatty Acid Oxidation and Lipogenesis in Mouse Primary Hepatocytes

Published on: August 27, 2015

20.7K

Related Experiment Videos

Last Updated: Dec 15, 2025

Quantitative Determination of De Novo Fatty Acid Synthesis in Brown Adipose Tissue Using Deuterium Oxide
07:34

Quantitative Determination of De Novo Fatty Acid Synthesis in Brown Adipose Tissue Using Deuterium Oxide

Published on: May 12, 2023

1.4K
Liquid Chromatography Coupled to Refractive Index or Mass Spectrometric Detection for Metabolite Profiling in Lysate-based Cell-free Systems
14:42

Liquid Chromatography Coupled to Refractive Index or Mass Spectrometric Detection for Metabolite Profiling in Lysate-based Cell-free Systems

Published on: September 23, 2021

5.5K
Determination of Fatty Acid Oxidation and Lipogenesis in Mouse Primary Hepatocytes
12:11

Determination of Fatty Acid Oxidation and Lipogenesis in Mouse Primary Hepatocytes

Published on: August 27, 2015

20.7K

Area of Science:

  • Biochemistry
  • Metabolic Pathways
  • Cellular Respiration

Background:

  • The tricarboxylic acid (TCA) cycle is recognized as essential for gluconeogenesis (GNG) in liver cells.
  • Fatty acids are often omitted as gluconeogenic precursors in biochemistry and nutritional biochemistry textbooks, despite historical evidence of their contribution to glucose synthesis.

Purpose of the Study:

  • To demonstrate how carbon atoms from fatty acid β-oxidation contribute to glucose synthesis through the TCA cycle and cytosolic GNG.
  • To clarify the fate of acetyl-CoA carbons within the TCA cycle during gluconeogenesis.

Main Methods:

  • Tracing the flow of carbon atoms through the mitochondrial TCA cycle.
  • Analyzing the incorporation of acetyl-CoA derived from fatty acid β-oxidation into glucose via cytosolic GNG.

Main Results:

  • Carbons from acetyl-CoA are retained in the TCA cycle, not lost as carbon dioxide.
  • Malate exiting the mitochondrion for GNG contains equal contributions from acetyl-CoA and oxaloacetate.
  • Fatty acids contribute carbon to glucose, supporting their role as gluconeogenic precursors.

Conclusions:

  • Fatty acid β-oxidation is a significant source of carbon for glucose production.
  • The TCA cycle acts as a conduit, integrating fatty acid-derived carbons into the gluconeogenic pathway.
  • Textbooks should include fatty acids as gluconeogenic precursors due to their established biochemical role in glucose synthesis.