The Effect of Lower Limb Neuromuscular Electrical Stimulation on Skeletal Muscle Signaling for Glucose Utilization and Systemic Inflammation After Acute Spinal Cord Injury

Abstract

<h3>Research Objectives</h3> To quantify the effects of a novel combination neuromuscular electrical stimulation (Comb-NMES) training program on muscle signaling for glucose utilization and systemic inflammatory blood markers in individuals with acute spinal cord injury (SCI). <h3>Design</h3> Randomized controlled clinical trial. <h3>Setting</h3> In-patient rehabilitation setting. <h3>Participants</h3> 12 participants between 30.3 ±8.6, with an SCI between C6-L1, within 14 days of the SCI and with no history of diabetes, participated in the study. Muscle samples were collected from the Vastus Lateralis muscle within 14 days of SCI and before discharge from the Spain Rehabilitation hospital. <h3>Interventions</h3> The intervention group received Comb-NMES training program that combines dynamic contractions (resistance training) via high-frequency electrical stimulation with twitch contractions (aerobic training) via low-frequency electrical stimulation on the quadriceps muscle group on both legs. The control group received (sham treatment) passive dynamic exercise of the lower legs and transcutaneous electrical nerve stimulation (TENS). Interventions were given 3 times/week for 3-4 weeks. <h3>Main Outcome Measures</h3> Western blot analysis was performed to quantify signaling proteins (GLUT4, AMPKα, Hexokinase II, CaMKII, Akt, AS160, IRS-1, ACC, GS, and PI3 Kinase) for muscle glucose uptake. In addition, assays were performed to measure the serum proinflammatory and anti-inflammatory cytokines (IFN-γ, IL-10, IL-12p70, IL-1β, IL-6, IL-8, AND TNF-α). <h3>Results</h3> Protein expression for Akt, AMPKα, AS160, CaMKII, GLUT4, Hexokinase II, and PI3 Kinase and circulating levels of anti-inflammatory cytokine IL-10 and IFN-γ increased following Comb-NMES training program. <h3>Conclusions</h3> This preliminary data suggests that Comb-NMES training may increase the expression of proteins for glucose uptake and utilization in the paralyzed skeletal muscle. In addition, Comb-NMES training may increase circulating anti-inflammatory cytokines. This trial is ongoing, and results may change with a larger sample size. <h3>Author(s) Disclosures</h3> All authors listed in this abstract have no conflict of interest. this study is funded by NIH.