Related Experiment Video
Updated: May 10, 2026
05:55
Tension-Free Weight-Bearing Model of Steroid-Induced Osteonecrosis of Femoral Head in Rats
Published on: September 27, 2024
Glucocorticoid-induced skeletal muscle atrophy
O Schakman1, S Kalista, C Barbé
1Laboratory of Cell Physiology, Institute of Neuroscience, B-1200 Brussels, Belgium.
The International Journal of Biochemistry & Cell Biology
|June 29, 2013
Summary
Glucocorticoids (GC) trigger muscle atrophy by increasing protein breakdown via the ubiquitin proteasome system and decreasing protein synthesis. Understanding these mechanisms is key to developing therapies for GC-induced myopathy.
Area of Science:
- Muscle physiology
- Endocrinology
- Molecular biology
Background:
- Muscle atrophy is linked to increased glucocorticoid (GC) levels in various pathological states.
- GC-induced muscle atrophy affects fast-twitch, glycolytic muscles, reducing fiber size and protein content.
Purpose of the Study:
- To review recent advancements in understanding the mechanisms of GC-induced muscle atrophy.
- To explore therapeutic strategies for GC-induced myopathy.
Main Methods:
- Review of literature on molecular mechanisms of muscle atrophy.
- Analysis of the role of atrogenes (e.g., FOXO, Atrogin-1, MuRF-1) in GC action.
- Examination of the impact on protein synthesis pathways (e.g., mTOR/S6K1) and growth factors (IGF-I, Myostatin).
Main Results:
- GCs increase muscle proteolysis through ubiquitin-proteasome and lysosomal systems.
- GCs inhibit muscle protein synthesis by suppressing the mTOR/S6K1 pathway.
- GCs alter the balance of anabolic (IGF-I) and catabolic (Myostatin) growth factors.
Conclusions:
- GCs induce muscle atrophy by disrupting protein turnover through specific molecular pathways.
- Targeting these pathways offers potential for treating GC-induced myopathy.
Keywords:
11β-HSD111β-hydroxysteroid dehydrogenase type 14E-BP1BCAABCATC/EBPCCAAT/enhancer binding proteinEDLFOXOGCGHSR1GRGREGSK3βGadd45GlucocorticoidsHATHDACHMBIGF-IIRS-1Insulin-like Growth Factor-IInsulin-like Growth FactorsKLF-15Kruppel-like factor 15LC3MYHCMstnMuRF-1MyostatinNFκBPDK4PI3KProtein synthesisProtein turnoverREDD1S6K1SARMSkeletal muscleUPSbranched-chain amino acidbranched-chain amino acid aminotransferaseeIF2BeIF3FeIF4Eeukaryotic initiation factor 2Beukaryotic translation initiation factor 3 subunit Feukaryotic translation initiation factor 4Eeukaryotic translation initiation factor 4E-binding protein 1extensor digitorum longusforkhead box Oglucocorticoid receptorglucocorticoid-responsive elementglucocorticoidsglycogen synthase kinase 3βgrowth arrest and DNA damagegrowth hormone secretagogue receptor 1histone acetyltransferaseshistone deacetylasesinsulin receptor substrate 1mTORmammalian target of rapamycinmiR1microRNA 1microtubule-associated protein light chain 3muscle RING-finger protein-1myosin heavy chainnuclear factor-kappa Bphosphatidylinositol 3′ kinasepyruvate dehydrogenase kinase 4regulated in development and DNA damage responses 1ribosomal protein kinase 1selective androgen receptor modulatorsiRNAsmall interfering RNAubiquitin proteasome systemβ-hydroxy-β-methylbutyrate
Related Concept Videos
01:26Cross-bridge Cycle
As muscle contracts, the overlap between the thin and thick filaments increases, decreasing the length of the sarcomere—the contractile unit of the muscle—using energy in the form of ATP. At the molecular level, this is a cyclic, multistep process that involves binding and hydrolysis of ATP, and movement of actin by myosin.
01:28Disorders of the Skeletal Muscle
The clinical conditions affecting the skeletal muscle tissue are broadly categorized as musculoskeletal and neuromuscular disorders.
Musculoskeletal disorders
Musculoskeletal disorders involve injuries and conditions affecting the skeletal muscles and associated connective tissues. These disorders can arise from acute biomechanical stresses or chronic overuse and can occur across different age groups. Common injuries include sprains, fractures, and muscular strains, often resulting from...
Musculoskeletal disorders
Musculoskeletal disorders involve injuries and conditions affecting the skeletal muscles and associated connective tissues. These disorders can arise from acute biomechanical stresses or chronic overuse and can occur across different age groups. Common injuries include sprains, fractures, and muscular strains, often resulting from...
01:20Myasthenia Gravis: Overview and Treatment
Myasthenia gravis is a neuromuscular transmission disorder characterized by weakness and increased fatigability of skeletal muscles. It is an autoimmune disease affecting approximately one in 2000 people, where antibodies against the α1 subunit of nicotinic acetylcholine receptors are produced.
These antibodies interfere with the function of the nicotinic receptors in three ways: by binding to the receptor and disrupting acetylcholine binding; by causing cross-linking of receptors which leads...
These antibodies interfere with the function of the nicotinic receptors in three ways: by binding to the receptor and disrupting acetylcholine binding; by causing cross-linking of receptors which leads...
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...
01:21Drugs for Treatment of Crohn's Disease in IBD Using Glucocorticoids
Glucocorticoids, a class of anti-inflammatory drugs, are pivotal in treating moderate to severe Crohn's disease by inducing remission. They exhibit their anti-inflammatory action by inhibiting the production of inflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-1, and chemokines like IL-8. In addition, they reduce the expression of inflammatory cell adhesion molecules and inhibit gene transcription of nitric oxide synthase, phospholipase A2, cyclooxygenase-2 (COX-2),...
01:15Hypoglycemia and Glucagon
Without prolonged fasting, healthy individuals maintain blood glucose levels above 3.5 mM due to a well-adapted neuroendocrine counterregulatory system that effectively prevents acute hypoglycemia, a potentially life-threatening condition. The primary clinical scenarios for hypoglycemia encompass diabetes treatment, inappropriate production of endogenous insulin or insulin-like substances by tumors, and the use of glucose-lowering agents in non-diabetic individuals. Notably, hypoglycemia in the...