Mechanistic Insights Into Overloading-Induced Terminal Differentiation of TMJ Condylar Cartilage at the Single Cell...

Area of Science:

• Biomedical Engineering
• Molecular Biology
• Orthopedics

Background:

• Temporomandibular joint (TMJ) degeneration is increasing, with overloading as a key risk factor.
• Condylar cartilage degeneration significantly impacts patient quality of life.
• Molecular mechanisms and effective treatments for TMJ degeneration remain elusive.

Purpose of the Study:

• To investigate the molecular mechanisms of condylar cartilage degeneration under overloading stress.
• To identify key genes and pathways regulating chondrocyte differentiation in the TMJ.
• To provide a theoretical basis for developing targeted TMJ degeneration therapies.

Main Methods:

• Single-nucleus RNA sequencing (snRNA-seq) of condylar cartilage in an overloading mouse model.
• Pseudotime trajectory and cellchat analyses to identify key regulatory genes and pathways.
• In vitro validation of identified gene functions.

Main Results:

• Identified 11 distinct cell types within condylar chondrocytes.
• Discovered Acvr1b and its associated signaling pathway as crucial for chondrocyte terminal differentiation.
• Revealed key molecular pathways involved in TMJ cartilage degeneration.

Conclusions:

• Acvr1b plays a critical role in regulating chondrocyte differentiation in response to overloading.
• The identified pathways offer potential targets for therapeutic interventions in TMJ degeneration.
• This study provides foundational insights into the molecular basis of TMJ cartilage pathology.