Effects of therapeutic magnetic stimulation on acute muscle atrophy in rats after hindlimb suspension

Functional Magnetic Neuromuscular Stimulation vs. Routine Physiotherapy in the Critically Ill for Prevention of ICU Acquired Muscle Loss: A Randomised Controlled Trial

Background and Objectives: Muscle loss is a known complication of ICU admission. The aim of the study was to investigate the effect of neuromuscular functional magnetic stimulation (FMS) on quadriceps muscle thickness in critically ill patients. Materials and Methods: Among ICU patients one quadriceps was randomized to FMS (Tesla Stym, Iskra Medical, Ljubljana, Slovenia) stimulation and the other to control care. Quadriceps thickness was measured by ultrasound (US) in transversal and longitudinal planes at enrolment, Days 3-5, and Days 9-12. The trial stopped early following an interim analysis comparing muscle thickness differences between groups using repeated measures ANOVA. Results: Of 18 patients randomized, 2 died before completing the trial. The final analysis reported included 16 patients (female 38%, age 68 ± 10 years, SOFA 10.8 ± 2.7). Three mild skin thermal injuries were noted initially, which were later avoided with proper positioning of FMS probe. Primary outcome comparison showed that quadriceps thickness in transversal and longitudinal planes decreased in the non-stimulated legs and, but it did not change in FMS legs (-4.1 mm (95%CI: -9.4 to -0.6) vs. -0.7 mm (95%CI: -4.1 to -0.7) (p = 0.03) and -4.4 mm (95%CI: -8.9 to -1.1) vs. -1.5 mm (95%CI: -2.6 to -2.2) (p = 0.02), respectively) (ANOVA difference between groups p = 0.036 and 0.01, respectively). Conclusions: In the critically ill, neuromuscular FMS is feasible and safe with precautions applied to avoid possible skin thermal injury. FMS decreases the loss of quadriceps muscle thickness.

A Prospective, Open-Label Study to Evaluate Functional Changes Following Electromagnetic Muscle Stimulation of Abdominal Muscle

Background

Electromagnetic muscle stimulation (EMMS) is an effective, well-tolerated noninvasive body contouring treatment for strengthening, toning, and firming the abdomen.

Objectives

In this study, functional changes following abdominal EMMS treatment wereevaluated.

Methods

In this prospective, open-label study, adults received 8 abdominal EMMS treatments (2 treatments on nonconsecutive days/week over 4 weeks). Follow-ups occurred 1 month (primary endpoint), 2, and 3 months postfinal treatment. Effectiveness endpoints included improvements from baseline on Body Satisfaction Questionnaire (BSQ; primary endpoint), core strength (timed plank test), abdominal endurance (curl-up test), and Subject Experience Questionnaire (SEQ). Safety was evaluated throughout.

Results

Sixteen participants (68.8% female) were enrolled, with a mean age of 39.3 years and a mean BMI of 24.4 kg/m²; 14 participants completed the study per protocol. Mean BSQ scores were significantly improved from baseline (27.9) to the 1-month follow-up (36.6; P < .05). Core strength and abdominal endurance were significantly greater at the 1-, 2-, and 3-month posttreatment time points than at baseline (P < .05). Frequently cited reasons for seeking EMMS treatment included a desire to feel stronger (100%; n = 14/14) and to improve athletic performance (100%; n = 14/14). SEQ responses 3 months posttreatment showed that most participants reported feeling stronger (92.9%) and motivated to receive additional EMMS treatments (100%) and work out to maintain treatment results (100%). The majority of participants (>78%) reported being "satisfied" or "very satisfied" with abdominal treatment 1 month posttreatment. One device- and/or procedure-related adverse event of menstrual cycle irregularity was reported in 1 participant and was mild in severity.

Conclusions

EMMS treatment of the abdomen is associated with functional strength improvements and high patient satisfaction.

Level of Evidence 4

The ultrastructure of muscle fibers and satellite cells in experimental autoimmune encephalomyelitis after treatment with transcranial magnetic stimulation

In this study, we investigated the effect of transcranial magnetic stimulation (TMS) on the ultrastructure of muscle fibers and satellite cells in rats with experimental autoimmune encephalomyelitis (EAE). EAE-induced animals were treated with TMS (60 Hz at 0.7 mT) for 2 hours in the morning, once a day, 5 days a week, for 3 weeks, starting on day 15 post-immunization. The rats were sacrificed on day 36 post-immunization, and the soleus muscles were evaluated by light microscopy and transmission electron microscopy. Findings were compared with a non-treated EAE group. Electron microscopy analysis showed the presence of degenerated mitochondria, autophagic vacuoles, and altered myofibrils in non-treated EAE group. This correlates with the presence of acid phosphatase activity in muscle fibers and core-targetoid lesions with desmin immunohistochemistry. Most myonuclei in the EAE group showed apoptotic features. In contrast, EAE induced-TMS treated animals had less ultrastructural changes in the mitochondria and the myofibrils, together with less frequent apoptotic nuclear features. Peripheral desmin+ protrusions, as a marker of active satellite cells, were significantly increased in TMS-treated group. This correlates ultrastructurally with the presence of active features in satellite cells in the TMS group. In conclusion, the attenuation of ultrastructural alterations in muscle fibers and activation response of satellite cells caused by EAE indicated that skeletal muscle had a regenerative response to TMS.

Electromagnetic muscle stimulation: A retrospective study of patient experience

Background

Electromagnetic muscle stimulation (EMMS) is a non‐invasive body contouring technology for strengthening, firming, and toning the abdomen, buttocks, and thighs that is associated with high patient satisfaction.

Aims

To gain a greater understanding of factors contributing to patient satisfaction with EMMS.

Methods

This was a retrospective, non‐comparative study of patient information and questionnaires regarding EMMS treatments to abdomen and/or buttocks collected July 1 to December 1, 2019 from clinical practices in the United States. Questionnaires collected and included for study analysis were the Subject Experience Questionnaire (SEQ), the Body Satisfaction Questionnaire (BSQ), and the Subject‐rated Global Aesthetic Improvement Scale (SGAIS).

Results

Responses from 146 treated patients were analyzed (abdomen only: n = 94; buttocks only, n = 30; abdomen and buttocks: n = 22). Patients were 79% female with mean age of 41.3 years (range: 19–73). Frequently cited reasons for seeking EMMS treatment were a desire to appear more toned (89%) or slimmer (42%), and to feel stronger (38%). BSQ and SGAIS scores were improved 4 weeks after treatment. On post‐treatment SEQ, most patients reported being “satisfied” or “very satisfied” with abdomen (83.2%; n = 89/107) or buttocks (57.4%; n = 27/47) treatment. Most patients reported feeling stronger after abdomen treatment, and across both body areas, patients were more confident, happier with their overall appearance, and motivated to work out and maintain treatment results.

Conclusion

This retrospective study of patient questionnaires provides important information on aesthetic and functional factors that can contribute to high patient satisfaction following EMMS treatment of the abdomen and/or buttocks.

Teriparatide and exercise improve bone, skeletal muscle, and fat parameters in ovariectomized and tail-suspended rats

INTRODUCTION

Although teriparatide (TPTD) and exercise may improve osteoporosis, muscle atrophy, and fat metabolism during ageing, the effects of treatment with a combination of TPTD and exercise on these factors remain unclear. Therefore, this study examined the effects of TPTD and exercise on bone, skeletal muscle, and fat in ovariectomized and tail-suspended rats.

MATERIALS AND METHODS

Seven-month-old female Wistar rats were ovariectomized and subjected to tail suspension. The rats were then randomized into one of the following four groups (n = 20/group) after 4 weeks: control group, treated with TPTD vehicle and no exercise; TPTD group (30 µg/kg TPTD, 3 days/week); Exercise group (treadmill at 12 m/min, 60 min/day, 5 days/week); and Combined group treated with TPTD and treadmill exercise. After 1 and 8 weeks of treatment, bone, skeletal muscle, and fat tissue parameters were evaluated.

RESULTS

TPTD improved bone mineral density (BMD), bone structure, bone strength at the femoral metaphysis, and the percentage of skeletal muscle mass, and decreased the percentage of fat mass and the adipose volume in the bone marrow. Treadmill exercise increased BMD, bone strength of cancellous bone, and the percentage of skeletal muscle mass, and decreased the percentage of fat mass as seen on dual-energy X-ray absorptiometry. Furthermore, combined treatment significantly affected BMD, bone structure, and bone strength of cortical bone at the femoral diaphysis.

CONCLUSION

TPTD or treadmill exercise improved bone, skeletal muscle, and fat mass. Combination therapy with TPTD and exercise had synergistic effects on BMD, structure, and bone strength in ovariectomized, tail-suspended rats.

Preventive Effects of Repetitive Peripheral Magnetic Stimulation on Muscle Atrophy in the Paretic Lower Limb of Acute Stroke Patients: A Pilot Study

Objective:

The aim of this study was to investigate the effect of repetitive peripheral magnetic stimulation (rPMS) on muscle atrophy prevention in the rectus femoris muscle (RF) of the paretic limb in acute stroke patients.

Methods:

Twelve acute stroke patients with a National Institute of Health Stroke Scale score >5 and a motor score of the paretic lower limb >2 at admission were divided into an intervention group (rPMS: mean age, 75±6.4 years) and a conventional care group (non-rPMS: mean age, 62±11.8 years). Baseline measurements were performed within 4 days of stroke onset. In the rPMS group, treatment was applied to the paretic thigh only for 2 weeks, 5 days a week, in addition to conventional care. The cross-sectional area (CSA) of the RF was assessed in both limbs using ultrasound at baseline and 2 weeks later. Data on patient characteristics were collected from the clinical records to assess correlations with the CSA rate of change.

Results:

Patients in the rPMS group were significantly older. Although the CSA of the RF did not change significantly on either side in the rPMS group, there was a significant decrease in the CSA on the paretic side in the non-rPMS group. However, no significant difference was observed in the CSA rate of change in the rPMS and non-rPMS groups. The CSA rate of change on the paretic side correlated negatively with age in the rPMS group.

Conclusions:

Our results suggest that rPMS prevents muscle atrophy more effectively in patients in their 60s than in patients more than 70 years old.

Variable spatial magnetic field influences peripheral nerves regeneration in rats

Generator of spatial magnetic field is one of most recent achievements among the magnetostimulators. This apparatus allows to obtain the rotating magnetic field. This new method may be more effective than other widely used techniques of magnetostimulation and magnetotherapy. We investigated the influence of alternating, spatial magnetic field on the regeneration of the crushed rat sciatic nerves. Functional and morphological evaluations were used. After crush injury of the right sciatic nerve, Wistar C rats (n = 80) were randomly divided into four groups (control and three experimental). The experimental groups (A, B, C) were exposed (20 min/day, 5 d/week, 4 weeks) to alternating spatial magnetic field of three different intensities. Sciatic Functional Index (SFI) and tensometric assessments were performed every week after nerve crush. Forty-eight hours before the sacrificing of animals, DiI (1,1'-di-octadecyl-3,3,3',3'-tetramethyloindocarbocyanine perchlorate) was applied 5 mm distally to the crush site. Collected nerves and dorsal root ganglia (DRG) were subjected to histological and immunohistochemical staining. The survival rate of DRG neurons was estimated. Regrowth and myelination of the nerves was examined. The results of SFI and tensometric assessment showed improvement in all experimental groups as compared to control, with best outcome observed in group C, exposed to the strongest magnetic field. In addition, DRG survival rate and nerve regeneration intensity were significantly higher in the C group. Above results indicate that strong spatial alternating magnetic field exerts positive effect on peripheral nerve regeneration and its application could be taken under consideration in the therapy of injured peripheral nerves.

Increased insulin sensitivity and distorted mitochondrial adaptations during muscle unloading

We aimed to further investigate mitochondrial adaptations to muscle disuse and the consequent metabolic disorders. Male rats were submitted to hindlimb unloading (HU) for three weeks. Interestingly, HU increased insulin sensitivity index (ISI) and decreased blood level of triglyceride and insulin. In skeletal muscle, HU decreased expression of pyruvate dehydrogenase kinase 4 (PDK4) and its protein level in mitochondria. HU decreased mtDNA content and mitochondrial biogenesis biomarkers. Dynamin-related protein (Drp1) in mitochondria and Mfn2 mRNA level were decreased significantly by HU. Our findings provide more extensive insight into mitochondrial adaptations to muscle disuse, involving the shift of fuel utilization towards glucose, the decreased mitochondrial biogenesis and the distorted mitochondrial dynamics.

Axonal supercharging technique using reverse end-to-side neurorrhaphy in peripheral nerve repair: an experimental study in the rat model

Object

In an attempt to improve peripheral nerve repair, the influence of the addition of reverse end-to-side neu-rorrhaphy for an injured peripheral nerve was investigated in the rat sciatic nerve transection model.

Methods

Twelve Sprague–Dawley rats were divided into two groups (six rats in each group). In Group I, the right sciatic nerve was cut at a point distal to the gluteal notch and repaired using end-to-end neurorrhaphy with four 10-0 nylon epineurial sutures. In Group II, after performing the same procedure as in Group I, the left sciatic nerve was cut distally and passed through a subcutaneous tunnel to the right side. The proximal stump of the left sciatic nerve was coapted to the epineurial window of the right sciatic nerve distal to the injured point in an end-to-side fashion using 10-0 nylon epineurial sutures. The effects were evaluated using analgesimeter recordings for the hind paw, electrophysiological tests, measurement of the muscle contraction force, a double-labeling technique, weight measurement and histological examination of the gastrocnemius muscle, histological examination of the bilateral sciatic nerves, and immunofluorescent staining.

Results

Results from the many tests used to evaluate the reverse end-to-side neurorrhaphy technique indicated thatfunctional recovery of the denervated target organs was promoted by axonal augmentation.

Conclusions

The reverse end-to-side neurorrhaphy technique could be useful in peripheral nerve repair.