Microcurrent Electrical Nerve Stimulation Facilitates Regrowth of Mouse Soleus Muscle

Abstract

Microcurrent electrical nerve stimulation (MENS) has been used to facilitate recovery from skeletal muscle injury. However, the effects of MENS on unloading-associated atrophied skeletal muscle remain unclear. Effects of MENS on the regrowing process of unloading-associated atrophied skeletal muscle were investigated. Male C57BL/6J mice (10-week old) were randomly assigned to untreated normal recovery (C) and MENS-treated (M) groups. Mice of both groups are subjected to continuous hindlimb suspension (HS) for 2 weeks followed by 7 days of ambulation recovery. Mice in M group were treated with MENS for 60 min 1, 3, and 5 days following HS, respectively, under anesthesia. The intensity, the frequency, and the pulse width of MENS were set at 10 μA, 0.3 Hz, and 250 msec, respectively. Soleus muscles were dissected before and immediately after, 1, 3 and 7 days after HS. Soleus muscle wet weight and protein content were decreased by HS. The regrowth of atrophied soleus muscle in M group was faster than that in C group. Decrease in the reloading-induced necrosis of atrophied soleus was facilitated by MENS. Significant increases in phosphorylated levels of p70 S6 kinase and protein kinase B (Akt) in M group were observed, compared with C group. These observations are consistent with that MENS facilitated regrowth of atrophied soleus muscle. MENS may be a potential extracellular stimulus to activate the intracellular signals involved in protein synthesis.

High‐intensity interval training changes the expression of muscle RING‐finger protein‐1 and muscle atrophy F‐box proteins and proteins involved in the mechanistic target of rapamycin pathway and autophagy in rat skeletal muscle

“…Akt has emerged as a critical mediator of mTOR, whereby it regulates the initiation of protein translation by phosphorylating mTOR at Ser‐2448 (Bolster, Crozier, Kimball, & Jefferson, ). Other studies have indicated that mechanical stimulation might induce mTOR‐dependent protein synthesis through an Akt‐independent pathway (Goodman et al., ; Hornberger et al., ; Ohno et al., ). It would appear that the mechanical stimulation was responsible for increased protein expression of phosphorylated mTOR in this study without a significant change in the level of phosphorylated Akt Ser473 .…”

New aspects of microcurrent electrical neuromuscular stimulation in sports medicine

“…A treatment to facilitate the recovery of skeletal muscle atrophy is therefore needed. MENS shows promise as such a treatment and is confirmed to facilitate the regrowth of atrophied soleus muscle via the stimulation of protein synthesis 23) .…”

Effects of microcurrents and physical exercise on the abdominal fat in patients with coronary artery disease

“…Electrolipolysis techniques, using low frequency microcurrents and microamperes, are an innovative and effective method to help the lipolysis in a localized abdominal adipose tissue. The lipolysis effect by microcurrent is explained by an increase of adenosine triphosphate-ATP production, amino acid transport, and protein synthesis [16], [17] and [18] which promotes an increase of catecholamines' concentration, and consequently the activation of triglyceride lipase and hormone-sensitive lipase enzymes [19]. In addition, a thermal effect increases the blood flow and metabolism changes in membrane polarity, causing an increase of organelles' numbers responsible for cellular activities [16].…”