Myogenic program induction in mature fat tissue (with MyoD expression).

Area of Science:

• Cell Biology
• Molecular Biology
• Regenerative Medicine

Background:

• MyoD is a key transcription factor regulating muscle development.
• Mature adipocytes are terminally differentiated cells with limited plasticity.
• Understanding cell fate conversion is crucial for regenerative therapies.

Purpose of the Study:

• To investigate the potential of MyoD gene transfer to induce myogenic transdifferentiation in mature adipocytes.
• To characterize the morphological and molecular changes during adipocyte-to-muscle conversion.
• To assess the feasibility and tolerance of this process in vitro and in vivo.

Main Methods:

• Organotypic cultures of fat tissue and long-term in vitro adipocyte cultures.
• MyoD gene transfer into mature adipocytes.
• In vivo studies using rat interscapular and inguinal fat pads.
• Analysis of morphological changes, fat content, and protein expression (muscle and adipocyte markers).

Main Results:

• MyoD induced significant morphological changes in adipocytes, including fat loss and acquisition of a fusiform shape.
• Transdifferentiated cells exhibited expression of muscle lineage proteins, co-existing with adipocyte markers initially.
• In vivo studies confirmed muscle protein expression and gradual reduction in fat content and adipocyte markers over time.
• The transdifferentiation process did not necessitate cell cycle progression and was well-tolerated by mature adipocytes.

Conclusions:

• MyoD gene transfer effectively induces myogenic transdifferentiation in mature adipocytes.
• Adipocyte-to-muscle conversion is achievable in terminally differentiated cells without cell division.
• This study demonstrates a potential strategy for generating muscle cells from adipocytes, relevant for regenerative medicine.