Silver Needle Thermal Therapy Improves Mitochondrial Injury in the Skeletal Muscle of MPS Rats by Inhibiting the TRPV1/CaMKII Pathway.

The objective of this study is to elucidate the therapeutic mechanisms underlying silver needle thermal therapy (SNT) in alleviating skeletal muscle mitochondrial damage in a rat model of myofascial pain syndrome (MPS), with particular emphasis on its regulatory role concerning TRPV1/CaMKII. The MPS rat model was established through blunt impact and eccentric movement. Interventions included SNT and local intramuscular injections of anti-TRPV1 miRNA. Behavioral assessments were conducted to measure the mechanical and thermal pain thresholds of the rats. Histopathological staining was performed to evaluate muscle structure, while mitochondrial damage was assessed using transmission electron microscopy. Western blotting analysis was employed to quantify expression levels of TRPV1, CaMKII, and CytC. Additionally, immunofluorescence techniques were applied to analyze both the expression levels of TRPV1 and its co-localization with CaMKII. Following administration of SNT and anti-TRPV1 miRNA injections, a downregulation in the expression levels of TRPV1, CaMKII, and CytC within the muscle tissue of MPS rats was observed; concurrently, mitochondrial damage exhibited improvement. The implementation of SNT and the inhibition of TRPV1 lead to a reduction in CaMKII, thereby alleviating mitochondrial damage, indicating that TRPV1 is a potential target for silver needle thermal therapy of MPS. Key words SNT " MPS " Mitochondria " TRPV1 " CaMKII.