Regeneration of Injured Tibialis Anterior Muscle in Mice in Response to Microcurrent Electrical Neuromuscular Stimulation with or without Icing

Abstract

Objective: Cold therapy, so-called icing, is often used immediately after muscle injuries as first aid for the suppression of inflammation and pain relief. Recent evidences show icing retards the regeneration of injured skeletal muscle. On the other hand, microcurrent electrical neuromuscular stimulation (MENS) promotes the regeneration of injured skeletal muscle. In this study, we investigated the effects of the MENS with or without icing on the regeneration of injured skeletal muscle. Methods: Eight-week-old male mice (C57BL/6J) were divided into 4 groups: control (C), cardiotoxin (CTX) injected (X), CTX injected with MENS (XM), and CTX injected with combined treatments with icing and MENS (XIM) groups. Necrosis-regeneration cycle was induced by an intramuscular injection of CTX into tibialis anterior (TA) muscles except for C group. After CTX-injection, the hindlimbs of the mice were soaked in ice-cold water (4ºC) for 20 minutes under anesthesia (XIM). After the treatments, both right and left hindlimbs of the mice in XIM and XM groups were treated with MENS (10 µA, 0.3 Hz, 250 msec) for 60 min a day and 3 days per week for 1 or 3 weeks. One and three weeks after CTX injection, TA muscles were dissected. Results: MENS with or without icing facilitated the recovery of muscle protein content and muscle fiber morphology including mean fiber cross-sectional areas of injured TA muscle, compared with non-treated condition. These facilitating effects of MENS with or without icing were accompanied with the increase in the relative number of Pax7-positive nuclei, namely satellite cells. Judging from fiber morphology, MENS with icing had enhanced stimulating effects on the regeneration of injured skeletal muscle, compared with MENS-treated condition. Conclusion: Evidence suggested that MENS with or without icing facilitated the regeneration of injured TA muscle. A combination treatment of MENS with icing might be a useful therapy for sports-related skeletal muscle injuries.

New aspects of microcurrent electrical neuromuscular stimulation in sports medicine

“…While icing on injured tissues immediately after an injury is generally believed to suppress pain and swelling, an icing-associated delay of skeletal muscle repair has been reported 25,26) . Our experiment on the combined treatment of MENS and icing had no observable effect on the regenerative process of injured skeletal muscle 24) .…”

“…The MENS treatment also increased muscle satellite cells, a key player in muscle regeneration, and accelerated muscle regeneration by stimulating muscle protein synthesis 2) . We also investigated the effect of MENS combined with icing, a common first-aid treatment in sports-associated injuries, on the regeneration of injured skeletal muscles 24) . While icing on injured tissues immediately after an injury is generally believed to suppress pain and swelling, an icing-associated delay of skeletal muscle repair has been reported 25,26) .…”

Effect of Combination Microcurrent Electrical Neuromuscular Stimulation and Hyperbaric Oxygen Therapy on the Regeneration of Injured Skeletal Muscle in Mice

“…It has no known side effects, and it can be delivered with a compact device 1) . There have been reports that MENS facilitates the repair of soft tissue in the context of skeletal muscle injury [2][3][4][5][6] , ligament injury 7) , tendon injury 8) 9) , wound 10) , skin ulcer 11) , and bed-7 sore 12) . Fujiya et al 2) showed, in a study of injured skeletal muscle in mice, that MENS facilitated recovery of the muscle mass and fiber cross-sectional area (CSA).…”

“…Fujiya et al 2) showed, in a study of injured skeletal muscle in mice, that MENS facilitated recovery of the muscle mass and fiber cross-sectional area (CSA). Further, there has been some thought that MENS combined with icing might be a useful therapy for sports-related skeletal muscle injuries 3) . Hyperbaric oxygen (HBO) therapy is known to facilitate repair of damaged tissue [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] .…”