The purpose of this study was to identify the effect of cerebral ischemia on affected(Lt) and unaffected(Rt) side of soleus, plantaris and gastrocnemius muscle mass and determine the effect of exercise on affected and unaffected side on soleus, plantaris and gastrocnemius muscle mass during acute stage of stroke. Sixteen male Sprague-Dawley rate with 200-270g body weight were randomly divided into three groups: control, stroke, and exercise after stroke(St+Ex) group. The control group received sham operation and the stroke group and St+Ex group received transient right MCA(middle cerebral artery) occlusion operation. The St+Ex groups ran on a treadmill for 20min/day at 10m/min and $10^{\circ}$ grade for 6days. During the experimental period body weight and diet intake was measured every morning. On the 7th day after operation, muscles were dissected from both affected and unaffected side of hindlimb. Cerebral infarction of stroke and St+Ex groups were identified by staining with TCC for 30 minutes. The data were analyzed by Kruskal-Wallis test and Mann-Whitney U test using the SPSSWIN 9.0 program. Significance was accepted at the level of p<0.05. The results were summarized follows : 1) There were no significant difference of the body weight on the first day of experiment among 3 groups. Whereas on the 7th day, the body weight of both stroke group and St+Ex group were significantly smaller than that of control group. Body weight of St+Ex group on the 7th day tended to be larger than that of stroke group. 2) Total diet intake of both stroke group and St+Ex group were also significantly smaller than that of control group. While total amount of diet intake in St+Ex group tended to be larger than that of stroke group. 3) The weight of gastrocnemius muscle of affected side in stroke group significantly decreased compared to that of control group and the weight of soleus and plantaris muscle of affected side in stroke group tended to decrease compared to that of control group. 4) The weight of plantaris muscle of unaffected side in stroke group significantly decreased compared to that of control group and the weight of soleus and gastrocnemius muscle of unaffected side in stroke group tended to decrease compared to those of control group. 5) The weight of gastrocnemius muscle of affected side in stroke group significantly decreased compared to that of unaffected side and there was no significant difference of the weight of soleus and plantaris muscle in stroke group between affected side and unaffected side. 6) The weight of soleus, plantaris and gastrocnemius muscle of both affected side and unaffected side in St+Ex group had a tendency of increase compared to those of stroke group. The relative weight of soleus and gastrocnemius muscle of affected side and soleus muscle of unaffected side in St+Ex group had a tendency to increase compared to those of stroke group. Based on these results, exercise during acute stage of stroke might attenuate muscle atrophy of both affected and unaffected side of hindlimb muscles.
Journal of the Korean Society of Industry Convergence
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v.25
no.6_1
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pp.917-925
/
2022
The purpose of this study was to investigate the effect of wearing a soft knee brace during balance training on paretic side foot pressure and knee joint muscle strength in stroke patients. The recruited 20 stroke patients were randomized into 10 experimental group and 10 control group. All subjects were subjected to balance training, and only the experimental group was trained in balance while wearing a soft knee brace. Experimental group and the control group before and after the intervention showed significant increases in foot pressure and knee joint muscle strength on the paralyzed side (p<0.05), experimental group showed a significant increase in foot pressure and knee joint muscle strength compared to the control group (p<0.05). This study confirmed that wearing a soft knee brace had a positive effect on paretic side foot pressure and knee joint muscle strength in stroke patients.
Journal of The Korean Society of Integrative Medicine
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v.10
no.3
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pp.199-208
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2022
Purpose : The study aimed to examine gender-differences in muscle tone, elasticity, and stiffness of the erector spinae in young and old subjects. This study also aimed to assess the effect of aging on muscle tone, elasticity, and stiffness of the erector spinae in men and women, and compare the trend of the aging effect between the two gender groups. Methods : With the muscle in the relaxed state and subjects in the prone position, a myotonometer was used to quantify muscle tone, elasticity, and stiffness, of the erector spinae in 102 participants[46 males (29 young subjects, aged 22.48±2.23 years and 17 old subjects, aged 76.35±3.71 years), 56 females (40 young subjects, aged 20.38±1.43 years and 16 old subjects, aged 74.56±5.40 years)]. Results : The tone and stiffness of the erector spinae muscles were greater in men than in women for both age groups (p<.001-.01), while elasticity did not show a significant difference between men and women. For the direction of change, both male and female groups showed significantly increased tone and stiffness, and decreased elasticity with increasing age (p<.001). For age-related changes, a different tendency was observed between men and women. Men showed a greater increase in tone than women with aging. in contrast, both men and women exhibited a similar decrease or increase in elasticity and stiffness. Conclusion : Gender-differences in the erector spinae in terms of muscle tone and stiffness were observed. Regardless of the age, men had higher muscle tone and stiffness than women, but not elasticity. The erector spinae muscles showed age-related changes in all aspects of muscle tone, elasticity, and stiffness, in both men and women. Notably, men presented greater variation than women in the amount of increase of muscle tone with aging. These findings have implications for musculoskeletal therapeutic approaches, and gender-customized tuning may be indicated for designing exercise interventions to prevent and manage gender-sensitive muscular injuries or diseases and frailty.
Lee, Dong Kyu;Min, Young Sil;Yoo, Seong Su;Shim, Hyun Sub;Park, Sun Young;Sohn, Uy Dong
Biomolecules & Therapeutics
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v.26
no.6
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pp.546-552
/
2018
A comprehensive collection of proteins senses local changes in intracellular $Ca^{2+}$ concentrations ($[Ca^{2+}]_i$) and transduces these signals into responses to agonists. In the present study, we examined the effect of sphingosine-1-phosphate (S1P) on modulation of intracellular $Ca^{2+}$ concentrations in cat esophageal smooth muscle cells. To measure $[Ca^{2+}]_i$ levels in cat esophageal smooth muscle cells, we used a fluorescence microscopy with the Fura-2 loading method. S1P produced a concentration-dependent increase in $[Ca^{2+}]_i$ in the cells. Pretreatment with EGTA, an extracellular $Ca^{2+}$ chelator, decreased the S1P-induced increase in $[Ca^{2+}]_i$, and an L-type $Ca^{2+}$-channel blocker, nimodipine, decreased the effect of S1P. This indicates that $Ca^{2+}$ influx may be required for muscle contraction by S1P. When stimulated with thapsigargin, an intracellular calcium chelator, or 2-Aminoethoxydiphenyl borate (2-APB), an $InsP_3$ receptor blocker, the S1P-evoked increase in $[Ca^{2+}]_i$ was significantly decreased. Treatment with pertussis toxin (PTX), an inhibitor of $G_i$-protein, suppressed the increase in $[Ca^{2+}]_i$ evoked by S1P. These results suggest that the S1P-induced increase in $[Ca^{2+}]_i$ in cat esophageal smooth muscle cells occurs upon the activation of phospholipase C and subsequent release of $Ca^{2+}$ from the $InsP_3$-sensitive $Ca^{2+}$ pool in the sarcoplasmic reticulum. These results suggest that S1P utilized extracellular $Ca^{2+}$ via the L type $Ca^{2+}$ channel, which was dependent on activation of the $S1P_4$ receptor coupled to PTX-sensitive $G_i$ protein, via phospholipase C-mediated $Ca^{2+}$ release from the $InsP_3$-sensitive $Ca^{2+}$ pool in cat esophageal smooth muscle cells.
Tilapia cultured in fresh water were acclimated in sea water with daily increase of $5%_{\circ}$ of salinity and it was completely terminated at the 7th day (0 week). Each three tilapia acclimated were examined weekly based from 0 week to elucidate changes of chloride cells in gill, mineral contents and physical properties in muscle and biochemical characteristics in myofibrils. Chloride cells existed in gills were gradually developed in number and size by acclimation to sea water and became to almost constant state at the third week. Shearing value, compressing strength and content of minerals such as Mg, Na and K in muscle were showed remarkable increase by acclimation to sea water in comparison to those of muscle from tilapia reared in fresh water. Myofibrillar $Mg^{2+}-,\;Ca^{2+}-$ and $K^+(EDTA)-ATPase$ activities of tilapia acclimated in sea water also increased showing significant statistic difference (p<0.01) from those of tilapia reared in fresh water However. thermostability of myofibrils was dropped by acclimation to sea water. The increase of shearing value and compressing strength in the muscle of tilapia by acclimation to sea water would be attributed to the increase of myofibrillar ATPase activities which act to accelerate the decomposition rate of ATP. Therefore, it is suggested that this phenomenon associated with muscle contraction could be brought an improvement of texture of tilapia acclimated in sea water.
Purpose: The purpose of this study was to assess the effects of breathing techniques on trunk muscle activity and balance during Pilates reformer footwork exercises, comparing results both within and between groups before and after the intervention. Methods: Thirty-one adult women over the age of 20 were selected as subjects for this study. They were divided into a Pilates breathing group (n = 15) and a general breathing group (n = 16) using a randomized control group study design. A surface electromyogram was used to measure muscle activity within and between the groups before and after the reformer footwork exercise. Static balance measurements were taken while standing on two legs, and dynamic balance measurements were taken while standing on one leg. All measurements were taken three times, and the average values were used for analysis. Results: The results of the study showed that muscle activity increased with significant differences in the external oblique and transverse abdominal muscles after exercise in the pre-post comparison within the Pilates breathing group (p < 0.05). In the between-group comparison, there was a significant difference in the increase in muscle activity of the external oblique and transverse abdominal muscles in the Pilates breathing group (p < 0.05). In the pre-post comparison of static and dynamic balance within the Pilates breathing group, there was a significant increase (p < 0.05) after exercise. The Pilates breathing group also showed a significant increase even in the between-group comparison (p < 0.05). Conclusion: This study confirmed that reformer footwork exercise accompanied by Pilates breathing has positive effects on muscle activity and static balance ability of trunk muscles in adult women. Therefore, reformer footwork exercise accompanied by Pilates breathing can be presented as an effective exercise method to increase trunk stability and balance ability through the simultaneous activity of the trunk muscles.
This study was carried out to determine effects of electrical stimulation on the soleus, target muscle of the sciatic newt, of white rat normal muscles. The biometric, histochemical, ultrastructural observations were made. The following results were obtained. A daily electrical stimulation of the skeletal muscle of the normally-functioning rat caused an increase of girth and weight of the muscle fibers for 2 weeks. No noticeable change was observed afterwards. More specifically, the density of volume of the red muscle fiber increased. whereas the density of the white muscle fiber decreased. The electrical stimulation group(experimental group) showed hypertrophy of the muscle fibers and narrowing of the space between perimysium and endomysium. Normally, glycogen granules are accumulated regardless of classification of muscle fibers. In addition, the NADH-TR reaction results were in agreement with the biometric findings, in that the red muscle fibers significantly increased. The ultrastructural observations revealed that mitochondria was formed in the red muscle fiber parallel to the muscle fibers of normal muscle, while mitochondria was observed in the sarcomere region of the white muscle fiber. However, activation of mitochondria took place in the sarcolemma region of the muscle fiber, and generation of mitochondria was observed in the sarcomere region of the white muscle fiber.
Purpose : The aim of this study is to examine the effect of the phenol compound-cold therapy plus exercise therapy on the carrageenan(CAR)-induced muscle pain. Method : Mice were injected 0.1ml of 2% CAR into the gastrocmemius(GAS) muscle for the induction of muscle pain. After 4 hours from the injection of CAR, the cold therapy with 1% syringic acid was done to GAS muscle. After 2 hours from cold therapy, the exercise therapy such as muscle stretching, climing- and declining-movements was performed three times interval of 10 minutes in each experimental group. After 4, 10 and 24 hours from CAR-induced muscle pain, the measurements of muscle diameter, paw withdrawal latency(PWL) and, tail flick latency(TFL) were carried out. Results : In this study, the thickness of GAS muscle in CAR-induced muscle pain significantly increased compared with control. While, the thickness of GAS muscle adopted cold syringic acid-therapy with exercise-therapy group was significantly decreased than that of CAR-induced muscle pain. In the measurements of PWL and TFL, cold syringic acid-therapy with exercise-therapy group was remarkably increased than CAR-induced muscle pain group in PWL and TFL. All measurements were showed significantly different between the treated-group and the treated-time. Conclusions : From these results, it is suggested that the cold syringic acid-therapy with exercise-therapy such as muscle stretching, climing- and declining-movement was effective in the prevention of CAR-induced muscle pain by the decrease of muscle thickness and the increase of PWL and TFL.
Jo, Kyungae;Jang, Woo Young;Yun, Beom Sik;Kim, Jin Soo;Lee, Hyun-Sun;Chang, Yeok Boo;Suh, Hyung Joo
Food Science of Animal Resources
/
v.41
no.4
/
pp.623-635
/
2021
The effect of deer antler extract on muscle differentiation and muscle atrophy were evaluated to minimize muscle loss following aging. Various deer antler extracts (HWE, hot water extract of deer antler; FE, HWE of fermented deer antler; ET, enzyme-assisted extract of deer antler; UE, extract prepared by ultrasonication of deer antler) were evaluated for their effect on muscle differentiation and inhibition of 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR)-induced muscle atrophy in C2C12 cells. Morphological changes according to the effect of antler extracts on muscle differentiation were confirmed by Jenner-Giemsa staining. In addition, the expression levels of genes related to muscle differentiation and atrophy were confirmed through qRT-PCR. In the presence of antler extracts, the length and thickness of myotubes and myogenin differentiation 1 (MyoD1) and myogenic factor 5 (Myf5) gene expression were increased compared to those in the control group (CON). Gene expression of AMP-activated protein kinase (AMPK), MyoD1, and myogenin, along with the muscle atrophy factors muscle RING finger-1 (MuRF-1) and forkhead box O3a (FoxO3a) upon addition of deer antler extracts to muscle-atrophied C2C12 cells was determined by qRT-PCR after treatment with AICAR. The expression of MuRF-1 and FoxO3a decreased in the groups treated with antler extracts compared to that in the group treated with AICAR alone. In addition, gene expression of MyoD1 and myogenin in the muscle atrophy cell model was significantly increased compared that into the CON. Therefore, our findings indicate that antler extract can increase the expression of MyoD1, Myf5 and myogenin, inhibit muscle atrophy, and promote muscle differentiation.
The present study were designed to characterize the action mechanisms of acetylcholine (ACh)-induced endothelium-dependent relaxation in arteries precontracted with high $K^+$(70 mM). For this, we simultaneously measured both muscle tension and cytosolic free $Ca^{2+}$ concentration $([Ca^{2+}]_i)$, using fura-2, in endothelium-intact, rabbit carotid arterial strips. In the artery with endothelium, high $K^+$ increased both $[Ca^{2+}]_i$ and muscle tension whereas ACh $(10{\mu}M)$ significantly relaxed the muscle and increased $[Ca^{2+}]_i$. In the presence of $N^G$-nitro-L-arginine (L-NAME, 0.1 mM), ACh increased $[Ca^{2+}]_i$ without relaxing the muscle. In the artery without endothelium, high $K^+$ increased both $[Ca^{2+}]_i$ and muscle tension although ACh was ineffective. 4-DAMP (10 nM) or atropine $(0.1{\mu}M)$ abolished ACh-induced increase in $[Ca^{2+}]_i$ and relaxation. The increase of $[Ca^{2+}]_i$ and vasorelaxation by ACh was siginificantly reduced by either $3{\mu}M$ gadolinium, $10{\mu}M$ lanthanum, or by $10{\mu}M$ SKF 96365. These results suggest that in rabbit carotid artery, ACh-evoked relaxation of 70 mM $K^+$-induced contractions appears to be mediated by the release of NO. ACh-evoked vasorelaxation is mediated via the $M_3$ subtype, and activation of the $M_3$ subtype is suggested to stimulate nonselective cation channels, leading to increase of $[Ca^{2+}]_i$ in endothelial cells.
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