Blood Flow Restriction Therapy Stimulates Intercellular Mitochondria Transfer and Improves Muscle Regeneration and...

Area of Science:

• Sports Medicine
• Regenerative Medicine
• Mitochondrial Biology

Background:

• Rotator cuff (RC) tears are a leading cause of shoulder dysfunction.
• Muscle atrophy and degeneration impede recovery and increase retearing risk after RC repair.
• The mechanisms of blood flow restriction (BFR) for muscle regeneration are unclear and its application to RC injuries is unexplored.

Purpose of the Study:

• To investigate if BFR stimulates mitochondrial transfer from fibro-adipogenic progenitors (FAPs) to myocytes.
• To determine if BFR enhances muscle regeneration and improves shoulder function following RC injury.

Main Methods:

• Utilized Prrx1-Cre/MitoTag reporter mice to track FAP mitochondria.
• Modeled massive RC tears via tendon transection and denervation (TT+DN) in mice.
• Assessed BFR effects on mitochondrial transfer, muscle atrophy, fiber size, and gait parameters at 2 and 6 weeks post-injury.

Main Results:

• BFR increased FAP-mediated mitochondrial transfer in healthy and injured supraspinatus (SS) muscles.
• BFR treatment significantly reduced muscle atrophy, fatty infiltration, and fibrosis post-RC injury.
• Mice treated with BFR showed improved forepaw weightbearing and stride length at 6 weeks.

Conclusions:

• Blood flow restriction (BFR) significantly enhances muscle quality and shoulder function after rotator cuff injury.
• The observed benefits are linked to increased mitochondrial transfer from FAPs to myocytes.
• BFR presents a potential novel rehabilitation strategy for RC injuries and other muscle conditions.