Related Experiment Video
Updated: Jul 6, 2026
08:37
Assessment of Glutamine as a Fuel Source for Alveolar Macrophages Exposed to Chronic Ethanol Using an Extracellular Flux Bioanalyzer
Published on: November 15, 2024
Acute alcohol intoxication increases REDD1 in skeletal muscle
Charles H Lang1, Robert A Frost, Thomas C Vary
1Department of Cellular & Molecular Physiology, Penn State University College of Medicine, Hershey, Pennsylvania 17033, USA. clang@psu.edu
Alcoholism, Clinical and Experimental Research
|March 14, 2008
Summary
Acute alcohol intoxication increases REDD1 in fast-twitch muscle, but this does not explain the decrease in protein synthesis. Chronic alcohol feeding does not alter REDD1 levels, suggesting it is not involved in alcoholic myopathy.
Area of Science:
- Biochemistry
- Molecular Biology
- Physiology
Background:
- Alcohol (EtOH) intoxication impairs muscle protein synthesis by inhibiting mammalian target of rapamycin (mTOR).
- REDD1 (regulated in development and DNA damage response 1) protein overexpression inhibits mTOR activity.
- The role of REDD1 in EtOH-induced muscle protein synthesis inhibition is unclear.
Purpose of the Study:
- To investigate if REDD1 mediates the decrease in muscle protein synthesis caused by acute alcohol intoxication.
- To compare REDD1 expression in acute versus chronic alcohol exposure models.
Main Methods:
- Assessed REDD1 mRNA and protein levels in rat gastrocnemius muscle after acute EtOH administration using RNase protection assays and Western blotting.
- Examined mTOR signaling pathway components via immunoblotting.
- Determined REDD1 levels in rats chronically fed alcohol.
Main Results:
- Acute EtOH increased REDD1 mRNA and protein in fast-twitch gastrocnemius muscle, correlating with decreased 4E-BP1 phosphorylation (an mTOR activity marker).
- REDD1 changes were not observed in slow-twitch soleus muscle or heart.
- REDD1 was not elevated in chronic alcohol-fed rats, despite reduced protein synthesis markers.
Conclusions:
- Acute EtOH intoxication increases REDD1 in fast-twitch muscle via an unknown mediator, independent of corticosterone.
- Elevated REDD1 is not responsible for the acute decrease in muscle protein synthesis.
- REDD1 induction does not explain alcoholic myopathy in chronic alcohol-fed rats.
Related Concept Videos
02:37Oxidation of Alcohols
In this lesson, the oxidation of alcohols is discussed in depth. The various reagents used for oxidation of primary and secondary alcohols are detailed, and their mechanism of action is provided.
The process of oxidation in a chemical reaction is observed in any of the three forms:
The process of oxidation in a chemical reaction is observed in any of the three forms:
02:23Alcohols from Carbonyl Compounds: Reduction
Reduction is a simple strategy to convert a carbonyl group to a hydroxyl group. The three major pathways to reduce carbonyls to alcohols are catalytic hydrogenation, hydride reduction, and borane reduction.
Catalytic hydrogenation is similar to the reduction of an alkene or alkyne by adding H2 across the pi bond in the presence of transition metal catalysts like Raney Ni, Pd–C, Pt, or Ru. Aldehydes and ketones can be reduced by this method, often under mild to moderate heat (25–100°C) and...
Catalytic hydrogenation is similar to the reduction of an alkene or alkyne by adding H2 across the pi bond in the presence of transition metal catalysts like Raney Ni, Pd–C, Pt, or Ru. Aldehydes and ketones can be reduced by this method, often under mild to moderate heat (25–100°C) and...
01:24Muscle Recovery and Fatigue
Muscle fatigue refers to the decline in a muscle's ability to maintain the force of contraction after prolonged activity. It primarily stems from changes within muscle fibers. Even before experiencing muscle fatigue, one may feel tired and have the urge to stop the activity. This response, known as central fatigue, occurs due to changes in the central nervous system, namely the brain and spinal cord. While there is no single mechanism that induces fatigue, it may serve as a protective response...
01:21Skeletal Muscle Relaxants: Adverse Effects
Skeletal muscle relaxants are widely used for muscle paralysis and relieving pain following any muscle injury or stiffness. However, depending on the drug type, they can have adverse effects that range from mild to severe. Usually, nondepolarizing neuromuscular blockers have minimal side effects. For example, drugs like d-tubocurarine, cisatracurium, and rocuronium cause hypotension, whereas drugs like baclofen, when stopped abruptly, can lead to the recurrence of spastic conditions.
Unlike...
Unlike...
01:15Oxidations of Aldehydes and Ketones to Carboxylic Acids
Oxidation of aldehydes and ketones results in the formation of carboxylic acids. Aldehydes, bearing hydrogen next to the carbonyl group, are easily oxidized compared to ketones. This is because an aldehydic proton can easily be abstracted during oxidation.
Aldehydes readily undergo oxidation in strong oxidizing agents such as potassium permanganate and chromic acid. The oxidation can also be carried out using mild oxidizing agents such as silver oxide. In fact, aldehydes can be easily oxidized...
Aldehydes readily undergo oxidation in strong oxidizing agents such as potassium permanganate and chromic acid. The oxidation can also be carried out using mild oxidizing agents such as silver oxide. In fact, aldehydes can be easily oxidized...