The effects of aerobic exercise training on the age-related lipid peroxidation, Schwann cell apoptosis and ultrastructural changes in the sciatic nerve of rats

Gama

et al. 2017

Rev Bras Med Esporte

Introduction: Peripheral nerve adaptation is critical for strength gains. However, information about intensity effects on nerve morphology is scarce. Objective: To compare the effects of different intensities of resistance training on radial nerve structures. Methods: Rats were divided into three groups: control (GC), training with 50% (GF1) and training 75% (GF2) of the animal's body weight. The morphological analysis of the nerve was done by light and transmission electron microscopy. One-way ANOVA and the Tukey's post hoc test were applied and the significance level was set at p≤0.05. Results: Training groups had an increase of strength compared to GC (p≤0.05). All measured nerve components (mean area and diameter of myelin fibers and axons, mean area and thickness of the myelin sheath, and of neurofilaments and microtubules) were higher in GF2 compared to the other (p≤0.05). Conclusion: Results demonstrated greater morphological changes on radial nerve after heavier loads. This can be important for rehabilitation therapies, training, and progression.

Section: Discussionmentioning

confidence: 99%

“…ET attenuates oxidative reactions and preserves Schwann cells and myelin sheath from pathologic changes 5 . Meanwhile, RT increases motor unit activation and muscle coordination in well-trained men 6 .…”

Section: Introductionmentioning

confidence: 99%

Morphological Adjustments of the Radial Nerve Are Intensity-Dependent

Carbone

Gama

et al. 2017

Rev Bras Med Esporte

“…20,21 The importance of examining the effects of training on the right vagus nerve resides on the fact that the right vagus nerve innervates mainly the sinoatrial node which is of particular interest in regard to heart rate control during training.…”

Section: Discussionmentioning

confidence: 99%

Endurance training induces structural and morphoquantitative changes in rat vagus nerve

Pianca

Pithon‐Curi

et al. 2015

Rev Bras Med Esporte

Introduction: Many nervous system tissues and cells suffers positive changes when faced to exercise training. However, data on vagus nerve adaptation from exercise-induced study is absent. Objective: To analyze the effect of an endurance training on the vagus nerve morphology of rats. Methods: Wistar rats (6 months of age) were divided into two groups: control group (CG, n=8), and aerobic trained group (AT, n=8). AT was submitted to a treadmill training program of five times per week during 12 weeks. The maximum speed stipulated in the training protocol corresponded to 60% of the mean maximum intensity achieved by the group in the test of maximum effort. Results: Twelve weeks of treadmill training resulted in left ventricular hypertrophy in the AT group compared to CG. There was a significant increase in the area of both the myelinated and unmyelinated axons, and in the area of myelin sheath with training. The number of neurotubules and neurofilaments in myelinated fibers of aerobic trained group was significantly greater than CG (p≤0.05). Conclusion: Endurance training promoted significant increase in morphometric parameters of the vagus nerve in the same way it affect somatic nerves.

“…Exercise and physical training are known to have beneficial effects on the PNS (Booth et al, 2002; Wilson and Deschenes, 2005; Deschenes, 2011; Nishimune et al, 2014). Evidence has shown that physical training potentiates the muscular function of aged humans and animals and induces morphological, biochemical and physiological alterations in spinal motoneurons of young and middle-aged animals (Brown et al, 1992; Coggan et al, 1992; Nakano et al, 1997; Kanda and Hashizume, 1998; Shokouhi et al, 2008). Recently, Shokouhi et al (2008) reported that aerobic exercise protects the peripheral nerves from the action of time by attenuating oxidative reactions and preservation of myelin sheath and Schwann cells from pathological changes that may occur during the process of aging.…”

Section: Introductionmentioning

confidence: 99%

Effects of Strength Training and Anabolic Steroid in the Peripheral Nerve and Skeletal Muscle Morphology of Aged Rats

Silva

Ciena

et al. 2017

Front. Aging Neurosci.

Thirty male 20-month-old Wistar rats were divided into groups: IC—initial control (n = 6), FC—final control (n = 6), AC—anabolic hormone control (n = 6), ST—strength trained (n = 6) and STA—strength trained with anabolic hormone (n = 6). All groups were submitted to adaptation, familiarization and maximum load carrying test (MLCT). Strength training (6–8×/session with loads of 50%–100% MLCT, 3×/week and pause of 120 s) was performed in ladder climbing (LC) for 15 weeks. The administration of testosterone propionate (TP) was performed 2×/week (10 mg/kg) in animals in the AC and STA groups. After the experimental period, animals were euthanized and the tibial nerve and plantaris muscle removed and prepared for electron transmission and histochemistry. To compare the groups we used one-way ANOVA (post hoc Bonferroni), student’s t-tests for pre vs. post (dependent and independent variables) comparisons and significance level set at p ≤ 0.05. The following significant results were found: (a) aging decreased the number of myelinated axon fibers; (b) use of isolated TP increased the diameter of myelinated fibers, along with increased thickness of myelin sheath; (c) ST increased area of myelinated and unmyelinated fibers, together with the myelin sheath. These changes made it possible to increase the area occupied by myelinated fibers keeping their quantity and also reduce the interstitial space; and (d) association of anabolic steroid and ST increased the area of unmyelinated axons and thickness of the myelin sheath. Compared to ST, both strategies have similar results. However, Schwann cells increased significantly only in this strategy.