Platelet-derived growth factor receptor-α causes muscle knots and pain-like symptoms in a rat model of myofascial trigger points

Background: Chronic myofascial pain syndrome (MPS) is primarily caused by myofascial trigger points (MTrPs), which are small, tight knots in muscles. The study aimed to investigate the role of a specific protein receptor, PDGFR-α, in these painful muscle knots and to understand how it contributes to pain and muscle contraction.

Methods: Researchers examined muscle tissue from patients with MPS and used a rat model to study the effects of PDGFR-α. They conducted various tests to analyze the activation of PDGFR-α, observed muscle structure under a microscope, and measured pain-related behaviors in rats. They also identified proteins that interact with PDGFR-α and studied their impact on pain and muscle contraction.

Results:

• Human Tissue Analysis: Higher levels of activated PDGFR-α were found in the muscle tissue of MPS patients, correlating with the severity of their pain.
• Rat Model Findings: Activating PDGFR-α in rats led to behaviors indicating pain and caused muscle contraction. Blocking the JAK2/STAT3 signaling pathway, which is activated by PDGFR-α, reduced these pain behaviors and muscle contractions.
• Protein Interaction: A protein called COL1A1 was found to bind to PDGFR-α, enhancing its activation and contributing to pain and muscle contraction.

Conclusions: The study suggests that the activation of PDGFR-α, particularly through its interaction with COL1A1, plays a significant role in causing muscle pain and contractions associated with myofascial trigger points. Targeting this pathway could be a potential strategy for treating chronic myofascial pain syndrome.