scholarly journals Twenty-one days of low-intensity eccentric training improve morphological characteristics and function of soleus muscles of mdx mice

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Paulo S. Pedrazzani ◽  
Tatiana O. P. Araújo ◽  
Emilly Sigoli ◽  
Isabella R. da Silva ◽  
Daiane Leite da Roza ◽  
...  
Keyword(s):  
Soleus Muscle ◽  
Morphological Characteristics ◽  
Training Group ◽  
Mdx Mice ◽  
Eccentric Training ◽  
Active Force ◽  
Wild Type ◽  
Low Intensity ◽  
Sedentary Group ◽  
Group 3

AbstractDuchene muscular dystrophy (DMD) is caused by the absence of the protein dystrophin, which leads to muscle weakness, progressive degeneration, and eventually death due to respiratory failure. Low-intensity eccentric training (LIET) has been used as a rehabilitation method in skeletal muscles after disuse. Recently, LIET has also been used for rehabilitating dystrophic muscles, but its effects are still unclear. The purpose of this study was to investigate the effects of 21 days of LIET in dystrophic soleus muscle. Thirty-six male mdx mice were randomized into six groups (n = 6/each): mdx sedentary group; mdx training group-3 days; mdx training group-21 days; wild-type sedentary group; wild-type training group-3 days and wild-type training group-21 days. After the training sessions, animals were euthanized, and fragments of soleus muscles were removed for immunofluorescence and histological analyses, and measurements of active force and Ca2+ sensitivity of the contractile apparatus. Muscles of the mdx training group-21 days showed an improvement in morphological characteristics and an increase of active force when compared to the sedentary mdx group. The results show that LIET can improve the functionality of dystrophic soleus muscle in mice.

Exercise and clenbuterol as strategies to decrease the progression of muscular dystrophy in mdx mice

1996 ◽  
Vol 80 (3) ◽  
pp. 734-741 ◽  
Author(s):  
E. E. Dupont-Versteegden
Keyword(s):  
Body Weight ◽  
Muscular Dystrophy ◽  
Weight Ratio ◽  
Morphological Characteristics ◽  
Mdx Mice ◽  
Body Weight Ratio ◽  
Muscle Weight ◽  
Sedentary Group ◽  
Running Activity ◽  
Tetanic Tension

The effects of exercise and the combination of exercise and clenbuterol on progression of muscular dystrophy were studied in mdx mice. At 3 wk of age, mdx mice were randomly assigned to sedentary (MS), exercise (ME), or combined exercise and clenbuterol (MEC) groups. Clenbuterol was given in the drinking water (1.0-1.5 mg . kg body weight-1 . day-1), and exercise consisted of spontaneous running activity on exercise wheels. At 3 mo or 1 yr of age, ventilatory function, contractile properties, and morphological characteristics of the soleus (Sol) and diaphragm (Dia) muscles were measured. The mdx mice receiving clenbuterol ran less than the mice without clenbuterol. The combination of clenbuterol and exercise was associated with an increase in Sol muscle weight and a muscle weight-to-body weight ratio of 30-35% compared with the sedentary group and approximately 20% compared to exercise alone. Myosin and total protein concentrations of the Sol and Dia increased in the MEC group at 1 yr of age only. Normalized active tension was increased in the Dia at 1 yr of age in both the ME and MEC groups by approximately 30%. Absolute tetanic tension of the Sol was increased at both 3 mo and 1 yr of age in the MEC compared with the MS group. At 1 yr of age, there was an additional 23% increase compared with the ME group. Fatigability increased in the MEC group by approximately 25% in the Sol and Dia muscles at both ages compared with the MS and ME groups. Results indicate that exercise and exercise plus clenbuterol decrease the progression of muscular dystrophy. However, different mechanisms may be involved because the combination of clenbuterol and exercise resulted in increased fatigability and the development of deformities, whereas exercise alone did not. Therefore, clenbuterol may not be suitable for use in patients with muscular dystrophy.

scholarly journals Reduction in mdx mouse muscle degeneration by low-intensity endurance exercise: a proteomic analysis in quadriceps muscle of exercised compared with sedentary mdx mice

2015 ◽  
Vol 35 (3) ◽  
Author(s):  
Simona Fontana ◽  
Odessa Schillaci ◽  
Monica Frinchi ◽  
Marco Giallombardo ◽  
Giuseppe Morici ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Endurance Exercise ◽  
Proteomic Analysis ◽  
Quadriceps Muscle ◽  
Mdx Mouse ◽  
Mdx Mice ◽  
Muscle Degeneration ◽  
Wild Type ◽  
Mouse Muscle ◽  
Low Intensity

By proteomic analysis we found an up-regulation of four carbonic anhydrase-3 (CA3) isoforms and a down-regulation of superoxide dismutase [Cu-Zn] (SODC) in quadriceps of sedentary X-linked muscular dystrophy (mdx) mice as compared with wild–type (WT) mice and the levels were significantly restored to WT values following low-intensity endurance exercise.

scholarly journals Effects of Mechanical Over-Loading on the Properties of Soleus Muscle Fibers, with or without Damage, in Wild Type and Mdx Mice

PLoS ONE ◽  
2012 ◽  
Vol 7 (4) ◽  
pp. e34557 ◽  
Author(s):  
Masahiro Terada ◽  
Fuminori Kawano ◽  
Takashi Ohira ◽  
Naoya Nakai ◽  
Norihiro Nishimoto ◽  
...  
Keyword(s):  
Soleus Muscle ◽  
Muscle Fibers ◽  
Mdx Mice ◽  
Wild Type

Changes in H reflex and neuromechanical properties of the trapezius muscle after 5 weeks of eccentric training: a randomized controlled trial

2014 ◽  
Vol 116 (12) ◽  
pp. 1623-1631 ◽  
Author(s):  
Steffen Vangsgaard ◽  
Janet L. Taylor ◽  
Ernst A. Hansen ◽  
Pascal Madeleine
Keyword(s):  
Electrical Stimulation ◽  
Strength Training ◽  
Reference Group ◽  
Controlled Trial ◽  
Trapezius Muscle ◽  
Training Group ◽  
H Reflex ◽  
Eccentric Training ◽  
Voluntary Activity ◽  
Stimulation Of

Trapezius muscle Hoffman (H) reflexes were obtained to investigate the neural adaptations induced by a 5-wk strength training regimen, based solely on eccentric contractions of the shoulder muscles. Twenty-nine healthy subjects were randomized into an eccentric training group ( n = 15) and a reference group ( n = 14). The eccentric training program consisted of nine training sessions of eccentric exercise performed over a 5-wk period. H-reflex recruitment curves, the maximal M wave (Mmax), maximal voluntary contraction (MVC) force, rate of force development (RFD), and electromyographic (EMG) voluntary activity were recorded before and after training. H reflexes were recorded from the middle part of the trapezius muscle by electrical stimulation of the C3/4 cervical nerves; Mmax was measured by electrical stimulation of the accessory nerve. Eccentric strength training resulted in significant increases in the maximal trapezius muscle H reflex (Hmax) (21.4% [5.5–37.3]; P = 0.01), MVC force (26.4% [15.0–37.7]; P < 0.01), and RFD (24.6% [3.2–46.0]; P = 0.025), while no significant changes were observed in the reference group. Mmax remained unchanged in both groups. A significant positive correlation was found between the change in MVC force and the change in EMG voluntary activity in the training group ( r = 0.57; P = 0.03). These results indicate that the net excitability of the trapezius muscle H-reflex pathway increased after 5 wk of eccentric training. This is the first study to investigate and document changes in the trapezius muscle H reflex following eccentric strength training.

G.P.3.11 Novel myostatin inhibitors increase muscle mass in wild-type and mdx mice

2007 ◽  
Vol 17 (9-10) ◽  
pp. 785 ◽  
Author(s):  
J. Lachey ◽  
A. Pullen ◽  
R. Pearsall ◽  
J. Seehra
Keyword(s):  
Muscle Mass ◽  
Mdx Mice ◽  
Wild Type ◽  
Increase Muscle Mass

scholarly journals Effect of topical fluoride on microshear bond strength of primary enamel to composite, microhardness of enamel and its surface morphology: An in vitro study

2019 ◽  
Vol 13 (4) ◽  
pp. 305-310
Author(s):  
Mina Biria ◽  
Sajedeh Namaei Ghasemi ◽  
Seyedeh Mahsa Sheikh-Al-Eslamian ◽  
Narges Panahandeh
Keyword(s):  
Bond Strength ◽  
Artificial Saliva ◽  
Morphological Characteristics ◽  
In Vitro Study ◽  
Vitro Study ◽  
Control Group ◽  
Modes Of Failure ◽  
Group 3 ◽  
Microshear Bond Strength

Background. This in vitro study aimed to evaluate the microshear bond strength (μSBS), microhardness and morphological characteristics of primary enamel after treating with sodium fluoride (NaF) and acidulated phosphate fluoride (APF). Methods. Forty-eight primary canines were cut into mesial and distal sections and assigned to five groups randomly: group 1 (immersed in saliva as a control), group 2 (treated with NAF and immersed in saliva for 30 minutes), group 3 (treated with APF and immersed in saliva for 30 minutes), group 4 (treated with NAF and immersed in saliva for 10 days), and group 5 (treated with APF and immersed in saliva for 10 days). Composite resin (Filtek Z250) was bonded on the specimens (n=15) for measuring the μSBS. After storage in 37°C artificial saliva for 24 hours, µSBS and Vickers hardness tests (10 readings) were performed. The data were analyzed using one-way ANOVA and Kolmogorov-Smirnov, Levene’s and Tukey HSD tests (P<0.05). Morphological analysis of enamel and modes of failure were carried out under a scanning electron microscope (SEM) on two remaining specimens. Results. Significant differences in μSBS were only noted between groups 2 and 4 (P=0.024). Group 3 showed a significant decrease in hardness after storage in artificial saliva (P<0.001), with a significantly lower hardness than the other groups (P<0.001). The SEM observations showed irregular particles in groups 3 and 5; uniform, smooth and thin coats were seen in groups 2 and 4. Conclusion. Fluoride therapy with NaF and APF gels prior to restorative treatments had no adverse effects on the microshear bond strength.

scholarly journals PO-191 The effect of hypoxic training at different simulated altitude on the antioxidant activity mediated by Nrf2 in mice skeletal muscle

2018 ◽  
Vol 1 (4) ◽  
Author(s):  
Weixiu Ji ◽  
Ying Zhang
Keyword(s):  
Skeletal Muscle ◽  
Antioxidant Activity ◽  
Oxygen Concentration ◽  
Training Group ◽  
Control Group ◽  
Simulated Altitude ◽  
Wild Type ◽  
High Quality ◽  
Hypoxic Training ◽  
Nrf2 Protein

Objective It is generally believed that the long-term hypoxic training could impact oxidation resistance. Nrf2-Keapl signaling pathway is a key pathway of cell oxidative stress reaction. This research attempts to investigate the role and mechanism of Nrf2 in oxidation resistance to hypoxic training of different oxygen concentration. Methods Part one, 8-week-old Nrf2 knockout mice and wild type mice were divided into normoxic control group (NC), simulated altitude of 3500m hypoxic training group (3500HT) and simulated altitude of 5000m hypoxic training group (5000HT) randomly and respectively. The mice run on treadmill in speed of 12 m/min, 1h/day, 6day/week, for 4 weeks. Oxygen concentration in hypoxia was 13.3% and 10%. Mice were treated for 4 weeks, 8h/day. 48 h after the last training, the mice were sacrificed and skeletal muscles of legs were collected. Western Blot tested Nrf2 and antioxidant enzyme protein. Antioxidant enzymes mRNA were tested by RT-PCR. High quality fluorescence measurement was used to test ROS levels in skeletal muscle. Part two, The 30 C57BL/6J mice were divided into three groups: control group (WC), hypoxia group (WH), hypoxic training group (WHT). The hypoxic training arrangement was same as before. After both the interventions, the mice were sacrificed and collected skeletal muscle of legs. The expression of Nrf2, Keap1 and p-Nrf2 were analyzed by western blot. High quality fluorescence assay was done to detect ROS level in skeletal muscle of mice. Results (1) Compared with the same type mice NC group, Nrf2 protein, the mRNA and protein of CAT, GPX-1, GCLm, the mRNA of SOD1, SOD2, HO-1 were increased in wild type mice 3500HT group. And the Nrf2 protein, the mRNA and protein of SOD1, SOD2, the mRNA of CAT, NQO-1, GCLc, GCLm mRNA, the protein of HO-1 were decreased, and the ROS levels was higher in wile type mice 5000HT group. The mRNA of CAT, HO-1 in Nrf2-KO mice 3500HT group were increased, the mRNA and protein of SOD1, the mRNA of SOD2, the protein of GCLc were decreased, but the GCLc mRNA was increased in Nrf2-KO mice 5000HT group. When compared with the same intervention wild type mice, the mRNA and protein of SOD1, GPX-1, SOD2, HO-1, the mRNA of CAT, NQO-1, GCLc, GCLm were decreased in Nrf2-KO mice 3500HT group. The mRNA of GCLm, NQO-1, the protein of GCLc, HO-1 were decreased, but the GCLc mRNA was increased. (2) Nrf2/Keap1 complex contents in mice skeletal muscle of WH and WHT groups were significantly increased compared with WC group respectively. The free Nrf2 in mice skeletal muscle of WH、WHT groups were significantly reduced compared with WC group respectively. After both types of intervention, free Keap1 had no change nearly in skeletal muscle of mice. Compared with WC group, p-Nrf2 in mice skeletal muscle of WH and WHT groups were significantly reduced. The ROS level in mice skeletal muscle of WHT group significantly increased compared with WC group mice. Conclusions: Hypoxia and hypoxia training three interventions could increase Nrf2/Keap1 combination in skeletal muscle of mice, reduce the volume of free Nrf2; Phosphorylation of Nrf2 in skeletal muscle of mice in hypoxia training group was significantly lower, which may be result in marked increase in ROS level. Conclusions (1) Hypoxic training could affect antioxidant activity via Nrf2 in mice skeletal muscle, which is connected with the oxygen concentration. (2) Moderate hypoxia training (at the altitude of 3500m) can promote the antioxidant activity via Nrf2. However, extremely hypoxic training (at the altitude of 5000m) can restrain the antioxidant activity via Nrf2 through the inhibition of Nrf2/Keap1 dissociation.  

scholarly journals MPC-02 REVIEW OF MEDULLOBLASTOMA FOR THE ASSESSMENT OF CONSENSUS IN PATHOLOGICAL DIAGNOSIS USING JPMNG CASES

2019 ◽  
Vol 1 (Supplement_2) ◽  
pp. ii22-ii22
Author(s):  
Atsushi Sasaki ◽  
Jyunko Hirato ◽  
Takeshi Inoue ◽  
Yonehiro Kanemura ◽  
Yoshinori Kodama ◽  
...  
Keyword(s):  
Diagnostic Testing ◽  
Molecular Data ◽  
Pathological Diagnosis ◽  
Nuclear Accumulation ◽  
Variable Degree ◽  
Wild Type ◽  
Molecular Analyses ◽  
Group 4 ◽  
Group 3 ◽  
Subgroup Classification

Abstract Medulloblastoma (MB) is now classified by WHO 2016 classification as “genetically defined” and “histologically defined” variants. The aim of this study is to search for consensus on pathological diagnosis and assess the correlation between the central pathological diagnosis and the molecular subgrouping. We performed the pathological and molecular analyses in a total of 176 JPMNG (The Japan Pediatric Molecular Neuro-Oncology Group) cases. The diagnosis of MB was made by three expert neuropathologists (AS, JH, and TH) without knowledge of the molecular data. Subgroup affiliation was determined by expression profiling of 22 medulloblastoma subgroup-specific genes using the nanoString nCounter system. Histologically, classic MBL accounted for approximately 80% of all MB cases. Genetic analyses of 176 cases revealed four distinct molecular subgroups: WNT (14%), SHH (27%), group 3 (16%), and group 4 (43%). The central review reached a diagnosis of AT/RT for 3 cases that had been diagnosed as MB by the local pathologists. Immunohistochemically, WNT MBs showed nuclear accumulation of β-catenin protein, but the immunoreactivity was patchy in approximately one-quarter of WNT cases. GAB1 often exhibited little or no reactivity in the SHH subgroup. No reliable staining was observed for YAP1. All D/N MBL (16 cases) or MBEN (6 cases) were defined as SHH tumors. All MBEN cases were in infants (&lt;3 years of age), and genetically subdivided into SHH-TP53 wild-type tumors. Variable degrees of anaplasia, including LC/A MB, occur across the genetic subgroups, and the LC/A MB WNT type was rare (2/24=8.3%) among WNT subgroups. This study demonstrated that the combination of morphological and molecular analyses can precisely diagnose MB. More robust, surrogate markers should be developed as ancillary diagnostic testing for subgroup classification. Further exploration of the clinical significance of the variable degree of LC/A histology and some subtypes (i.e. LC/A, WNT) will be necessary for risk stratification.

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