RESUMEN
[Purpose] We investigated the utility of wearable inertial and magnetic sensing modules for analyzing neck and trunk movements during the rolling over movement. [Participants and Methods] The participants were instructed to roll over from the supine to the side-lying position with three sensor units attached to their forehead, xiphoid process of the sternum, and abdomen. Experiments were conducted on two prescribed patterns: one emphasizing hip joint flexion and adduction, and the other focusing on scapular protraction and horizontal shoulder joint adduction in two healthy participants (one male and one female). The flexion and rotation angles of the neck and trunk were calculated using conventional spreadsheet software with data obtained from the sensors. The obtained values were compared for agreement with those derived from a three-dimensional (3D) motion analysis device. [Results] The cross-correlation coefficient for the flexion and rotation angles of the neck and trunk between the two measurement methods was approximately 0.85, and the root mean square (RMS) angle difference was approximately 5.0°. [Conclusion] Wearable inertial and magnetic sensors can be used to quantitatively evaluate neck and trunk movements during the rolling over movement.
RESUMEN
[Purpose] This study aimed to investigate the changes in the pain severity and muscle hardness of the multifidus and longissimus muscles of young and elderly patients with low back pain after neuromuscular joint facilitation treatment. [Participants and Methods] The participants were 13 young patients and 11 elderly patients with chronic low back pain. The neuromuscular joint facilitation lumbar approach was used in all participants. The muscle hardness of the multifidus and longissimus muscles was assessed at the L4 and L5 levels of the lumbar spine. The changes in pain severity of low back pain were assessed using a visual analogue scale before and after treatment. [Results] Visual analogue scale scores significantly decreased in both groups after treatment. The young group showed significant differences in muscle hardness pre- and post-intervention. In addition, except for the muscle hardness of the multifidus muscle before intervention, on the side with pain at the L5 level, longissimus muscle hardness was higher in the elderly, as compared to the young patient group. [Conclusion] Interventions with neuromuscular joint facilitation have an immediate effect on pain relief in young and elderly people with chronic low back pain and on muscle spasms in young people with chronic low back pain.
RESUMEN
[Purpose] The purpose of this study was to investigate the changes in blood flow velocity and the vascular diameter of vertebral arteries before and after neuromuscular joint facilitation interventions via the cervical spine approach in healthy adults. [Participants and Methods] We included 16 healthy adults (9 males and 7 females). The interventions were performed successively, separated by a one-week interval. The order of interventions was randomized. The blood-flow velocity and diameter of the vertebral artery were measured before and after the intervention. The neuromuscular joint facilitation group underwent neuromuscular joint facilitation neck flexion pattern and extension pattern training on the right side of the cervical spine, while the control group was asked to rest for 5â min. [Results] The neuromuscular joint facilitation group showed a significant increase in systolic blood flow velocity and mean blood flow velocity of the right vertebral artery after the intervention. In contrast, the control group showed no significant differences for any of the measured parameters after the intervention. [Conclusion] Neuromuscular joint facilitation intervention via the cervical spine approach may be recommended to improve vertebral artery function.
RESUMEN
[Purpose] This study investigated the effects of co-contraction resistance exercises of the transverse abdominal and pelvic floor muscles in middle-aged females with stress urinary incontinence. [Participants and Methods] We included 32 females with stress urinary incontinence and divided them into two groups: the inner muscle training group and the pelvic floor muscle group. The thickness of the transverse abdominal muscle was measured during four tasks: (1) rest, (2) maximum contraction of the transverse abdominal muscle, (3) maximum contraction of the pelvic floor muscle, and (4) maximum co-contraction of the transverse abdominal and pelvic floor muscles. In the latter three tasks, measurements were obtained while the participants performed resistance movements using a Thera-band®. A home program was conducted in both groups, and the intervention lasted for 8 weeks. [Results] The cure rates for SUI were 87.5% and 68.8% in the inner muscle training and pelvic floor muscle groups, respectively. After the intervention, the thickness of the transverse abdominal muscle significantly increased in the inner muscle training groups performing maximum co-contraction of the transverse abdominal and pelvic floor muscles and maximum contraction of the transverse abdominal muscle. [Conclusion] Inner muscle training exercises are more effective than pelvic floor muscle exercises in improving inner muscle function and urinary incontinence in middle-aged females.
RESUMEN
[Purpose] This study examined the measurement reliability and cooperative movement of the pelvic floor and transverse abdominal muscles. [Participants and Methods] The participants were seven healthy adult females. Transverse abdominal muscle thickness and bladder floor elevation were measured under the following conditions during active exercise and during resistance exercise: the resting state, maximum contraction of the transverse abdominal muscle, maximum contraction of the pelvic floor muscle, and maximum co-contraction of the transverse abdominal and pelvic floor muscles. Measurements were taken at rest and under each exercise condition. [Results] The intraclass correlation coefficients of transverse abdominal muscle thickness and bladder floor elevation showed high reproducibility under all conditions. The maximum contraction of the pelvic floor muscle showed a high correlation with the maximum co-contraction of the transverse abdominal muscle and pelvic floor muscle during resistance exercise. A significant regression line was found between transverse abdominal muscle thickness and bladder floor elevation under all conditions. The regression equation was as follows: transverse abdominal muscle thickness=0.113 bladder floor elevation+0.377 (r2=0.21). [Conclusion] This study demonstrated that the measurement reliability of the transverse abdominal and pelvic floor muscles is high, and that both muscles exhibit cooperative movement.
RESUMEN
Age-related regression of myelinated fibers in peripheral nerves of the lower limbs is strongly influenced by capillaries and results in balance dysfunction and falls. However, the temporal relationships between alteration patterns of myelinated fibers and capillaries have not yet been clarified. This study aimed to investigate age-related morphological and histological changes of both myelinated fibers and capillaries in peripheral nerves to clarify whether myelinated fibers or capillaries change earlier. Seven male Wistar rats each were randomly selected at 20 weeks (young group), 70 weeks (middle group), and 97 weeks (old group) for histological evaluations. The left and right tibial nerves were removed morphologically and histologically to examine myelinated fibers and capillaries. Axon diameter and myelin thickness were almost unaltered in the middle group compared with the young group but were significantly reduced in the old group when compared with the other two groups. However, the capillary diameter and number of microvascular branch points were substantially reduced in the middle group. The current study demonstrates that myelinated fibers of peripheral nerves show signs of regression in elderly rats, whereas capillaries start to reduce in middle-aged animals. In normal aging of the tibial nerve, capillaries may regress before myelinated fibers.
Asunto(s)
Envejecimiento , Capilares/anatomía & histología , Vaina de Mielina , Fibras Nerviosas Mielínicas , Nervio Tibial/anatomía & histología , Factores de Edad , Animales , Estudios Longitudinales , Masculino , Ratas , Ratas WistarRESUMEN
BACKGROUND: Regression of myelinated peripheral nerve fibers in the lower extremities contributes to sarcopenia and balance dysfunction in normal aging. This subclinical regression of myelinated fibers (MFs) is heavily influenced by alterations in microvasculature, though the mechanism underlying these age-related degenerative phenomena remains unclear. The aim of the present study was to examine age-related regressions in myelinated distal peripheral nerve fibers as well as capillary architecture in rats using both morphological and histochemical methods. RESULTS: MFs were categorized into tertiles of 'large', 'medium', and 'small' sizes based on the distribution of MF diameters. A two-way ANOVA was used to assess effects of fiber size (large/medium/small) and group (young/elderly) on myelin thickness, axon diameter, myelin perimeter, axon perimeter, and G-ratio (axon diameter/fiber diameter). Significant main effects were observed for both MF size and group with respect to all dimensions except for G-ratio. Values for fiber diameter (P < 0.01), myelin thickness (P < 0.01), axon diameter (P < 0.01), myelin perimeter (P < 0.01), and axon perimeter (P < 0.01) were significantly lower than those in the young group. Additionally, mean capillary diameter and number of microvascular branch points were significantly lower in the elderly group than in the young group. CONCLUSIONS: The present study demonstrated that spontaneous age-related regression predominantly occurs for all fiber sizes in the distal peripheral nerves and the capillary architecture. The results of the present study further suggest that both the distal MFs and capillaries in the peripheral nerve may simultaneously regress with aging.
Asunto(s)
Envejecimiento/patología , Capilares/patología , Vaina de Mielina/patología , Fibras Nerviosas Mielínicas/patología , Nervios Periféricos/patología , Análisis de Varianza , Animales , Axones/patología , Tamaño de la Célula , Imagenología Tridimensional , Masculino , Microscopía Confocal , Nervios Periféricos/irrigación sanguínea , Distribución Aleatoria , Ratas WistarRESUMEN
INTRODUCTION: We determined the effects of low-intensity exercise on the three-dimensional capillary structure and associated angiogenic factors in the soleus muscle of Goto-Kakizaki (GK) diabetic rats. METHODS: Four groups of male rats were studied: sedentary nondiabetic (Con), exercised nondiabetic control (Ex), sedentary GK, and exercised GK (GK+Ex). Rats in the Ex and GK+Ex groups were subjected to chronic low-intensity running on a treadmill (15 m/min, 60 min/session, 5 sessions/week for 3 weeks). RESULTS: Although mean capillary volume and diameter were lower in the GK compared with all other groups, low-intensity exercise increased both of these measures in GK rats. Mitochondrial markers, i.e., SDH activity and PGC-1α expression, and the levels of angiogenic factors were higher in the GK+Ex than all other groups. Exercise increased vascular endothelial growth factor (VEGF) protein levels and the VEGF-to-TSP-1 ratio, an indicator of angiogenesis, in GK rats. CONCLUSIONS: Combined, the results indicate that low-intensity exercise reduces some of the microcirculatory complications in type 2 diabetic muscles.
Asunto(s)
Proteínas Angiogénicas/metabolismo , Capilares/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Músculo Esquelético/metabolismo , Condicionamiento Físico Animal/fisiología , Carrera/fisiología , Animales , Capilares/patología , Diabetes Mellitus Tipo 2/patología , Diabetes Mellitus Tipo 2/terapia , Masculino , Microcirculación/fisiología , Músculo Esquelético/irrigación sanguínea , Neovascularización Fisiológica/fisiología , Condicionamiento Físico Animal/métodos , Ratas , Ratas WistarRESUMEN
A chronic decrease in neuromuscular activity (activation and/or loading) results in muscle atrophy and capillary regression that are due, in part, to the overproduction of reactive oxygen species. We have reported that antioxidant treatment with astaxanthin attenuates the overexpression of reactive oxygen species in atrophied muscles that, in turn, ameliorates capillary regression in hindlimb-unloaded rats. Astaxanthin supplementation, however, had little effect on muscle mass and fibre cross-sectional area. In contrast, intermittent loading of the hindlimbs of hindlimb-unloaded rats ameliorates muscle atrophy. Therefore, we hypothesized that the combination of astaxanthin supplementation and intermittent loading would attenuate both muscle atrophy and capillary regression during hindlimb unloading. As expected, 2 weeks of hindlimb unloading resulted in atrophy, a decrease in capillary volume and a shift towards smaller-diameter capillaries in the soleus muscle. Intermittent loading alone (1 h of cage ambulation per day) attenuated atrophy of the soleus, while astaxanthin treatment alone maintained the capillary network to near control levels. The combination of intermittent loading and astaxanthin treatment, however, ameliorated atrophy of the soleus and maintained the capillary volume and luminal diameters and the superoxide dismutase-1 protein levels near control values. These results indicate that intermittent loading combined with astaxanthin supplementation could be an effective therapy for both the muscle atrophy and the capillary regression associated with a chronic decrease in neuromuscular activity.
Asunto(s)
Capilares/efectos de los fármacos , Suspensión Trasera/fisiología , Miembro Posterior/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Atrofia Muscular/tratamiento farmacológico , Animales , Antioxidantes/farmacología , Suplementos Dietéticos , Masculino , Ratas , Ratas Sprague-Dawley , Xantófilas/farmacologíaRESUMEN
[Purpose] Peripheral nerve degradation associated with aging is linked to failure of interactions in capillary metabolism. The aim of this study was to morphologically investigate the age-related changes in the capillary architecture of the tibial nerve in spontaneous aging and with aerobic exercise intervention in rats. [Subjects] Male Sprague-Dawley rats (n=15) were used in the present study. [Methods] The rats were divided into control (Cont, n=5), elderly (Elder, n=5), and elderly with aerobic exercise (Elder+Ex, n=5) groups. Aerobic training of low intensity was performed for 10 weeks using a treadmill starting at 96 weeks of age by the Elder+Ex group. The capillary diameter, cross-sectional area and number of microvascular ramifications in the tibial nerve were compared among the Cont (20-week-old), Elder (106-week-old) and Elder+Ex groups using three-dimensional images gained from confocal laser scanning microscopy. [Results] The capillary diameter, cross-sectional area and number of microvascular ramifications in the Elder group were significantly smaller than those observed in the Cont and Elder+Ex groups. [Conclusion] These findings suggest that the capillaries in the peripheral nerve degrade with spontaneous aging and that aerobic exercise of low intensity promotes angiogenesis, and protects the capillary from oxidative stress.
RESUMEN
Introduction: This study is a cross-sectional study that investigated the factors influencing shoulder mobility in terms of pain, grip strength, and supraspinatus muscle thickness in patients with impaired shoulder mobility during chemotherapy after radical breast cancer surgery. Methods: This study included 165 female patients with unilateral breast cancer who had shoulder joint mobility disorders during chemotherapy within 3 months after surgery. The clinical examination included the maximum active range of motion of the shoulder (flexion, extension, abduction, adduction, external rotation, and internal rotation), pain score (visual analog scale [VAS]), grip strength, and supraspinatus muscle thickness. Results: During shoulder abduction, supraspinatus muscle thickness was greatest at 90°, lowest at 0°, and higher at 60° than at 30° (p < 0.01). The factors influencing the active movement of shoulder flexion were the VAS score, body weight, grip strength, and supraspinatus contraction rate (R2 = 0.295), while the factors influencing active shoulder abduction were the VAS score, body weight, grip strength, supraspinatus muscle thickness (drooping position), and supraspinatus contraction rate (R2 = 0.295). Moreover, the factors influencing the active movement of shoulder external rotation were age, VAS score, body weight, grip strength, and supraspinatus muscle thickness (drooping position) (R2 = 0.258). There were no significant results from multiple linear regressions for shoulder extension, adduction, or internal rotation. Conclusion: Pain, weight, grip strength, supraspinatus muscle thickness, and supraspinatus distensibility are the main factors affecting shoulder flexion, abduction, and external rotation. In addition, supraspinatus muscle thickness and contraction rate may be a new index for assessing shoulder dysfunction.
RESUMEN
INTRODUCTION: The capillary architecture in skeletal muscles is unique in that it has anastomoses that interconnect individual capillaries. METHODS: We used new techniques to measure velocity of red blood cells (V(RBC) ) in both capillaries and anastomoses in situ. The volume of capillaries/anastomoses was determined, and the levels of several angiogenic regulators were compared between the soleus and the superficial gastrocnemius (LG(sup) ). RESULTS: The V(RBC) in both capillaries and anastomoses was slower in soleus than in LG(sup) . The numbers of capillaries and anastomoses were higher, diameter of capillaries smaller, and tortuosity greater in soleus than in LG(sup) . Consequently, the capillary/anastomoses volume was larger in soleus than in LG(sup) . Furthermore, several angiogenic regulators (HIF-1α, VEGF, Flt-1, KDR, angiopoietin-1 and -2, and Tie-2) were higher in soleus than in LG(sup) . CONCLUSION: The differences in microvascular architecture, V(RBC) , and levels of angiogenic regulators between soleus and LG(sup) reflect the greater oxygen demands of the highly active soleus muscle.
Asunto(s)
Capilares/fisiología , Hemodinámica/fisiología , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/metabolismo , Análisis de Varianza , Angiopoyetina 1/genética , Angiopoyetina 1/metabolismo , Angiopoyetina 2/genética , Angiopoyetina 2/metabolismo , Animales , Anastomosis Arteriovenosa/fisiología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Presión Sanguínea/fisiología , Femenino , Miembro Posterior/irrigación sanguínea , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Músculos/fisiología , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Estadística como Asunto , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
The purpose of this study was to examine whether exercise training can prevent microangiopathy of skeletal muscles in rats with type 2 diabetes and if succinate dehydrogenase (SDH) activity, an indicator of mitochondrial oxidative enzyme activity, is involved in the prevention of microangiopathy. Six-week-old male Goto-Kakizaki (GK) rats and age-matched male Wistar rats (control group (Con)) were used. GK rats were randomly assigned to nonexercise (DB) and exercise (DBEx) groups. The DBEx group was trained on a treadmill 5 times a week for 3 weeks. No significant differences in the capillary-to-fibre ratio or the capillary density were observed between the 3 groups. The luminal capillary diameter of the DB group was significantly lower than that of the Con group, whereas the capillary diameter of the DBEx group was significantly higher than that of the DB group. In addition, SDH activity was significantly higher in the DBEx group than in the Con and DB groups. Microangiopathy of skeletal muscles in type 2 diabetes was correlated with a decrease in the luminal capillary diameter, which was prevented by exercise training. Thus, the mitochondrial oxidative capacity appears to be involved in the overall mechanism by which exercise prevents microangiopathy.
Asunto(s)
Capilares/patología , Diabetes Mellitus Tipo 2/patología , Músculo Esquelético/irrigación sanguínea , Condicionamiento Físico Animal , Fosfatasa Alcalina/metabolismo , Animales , Glucemia , Capilares/metabolismo , Activación Enzimática , Masculino , Microscopía Confocal , Fibras Musculares Esqueléticas/enzimología , Fibras Musculares Esqueléticas/patología , Músculo Esquelético/enzimología , Músculo Esquelético/patología , Oxidación-Reducción , Ratas , Ratas Wistar , Succinato Deshidrogenasa/metabolismoRESUMEN
Type 2 diabetes mellitus is linked to impaired skeletal muscle glucose uptake and storage. This study aimed to investigate the fiber type distributions and the three-dimensional (3D) architecture of the capillary network in the skeletal muscles of type 2 diabetic rats. Muscle fiber type transformation, succinate dehydrogenase (SDH) activity, capillary density, and 3D architecture of the capillary network in the soleus muscle were determined in 36-week-old Goto-Kakizaki (GK) rats as an animal model of nonobese type 2 diabetes and age-matched Wistar (Cont) rats. Although the soleus muscle of Cont rats comprised both type I and type IIA fibers, the soleus muscle of GK rats had only type I fibers. In addition, total SDH activity in the soleus muscle of GK rats was significantly lower than that in Cont rats because GK rats had no high-SDH activity type IIA fiber in the soleus muscle. Furthermore, the capillary diameter, capillary tortuosity, and microvessel volume in GK rats were significantly lower than those in Cont rats. These results indicate that non-obese diabetic GK rats have muscle fiber type transformation, low SDH activity, and reduced skeletal muscle capillary content, which may be related to the impaired glucose metabolism characteristic of type 2 diabetes.
Asunto(s)
Capilares/patología , Diabetes Mellitus Tipo 2/enzimología , Diabetes Mellitus Tipo 2/patología , Músculo Esquelético/enzimología , Músculo Esquelético/patología , Succinato Deshidrogenasa/metabolismo , Animales , Capilares/enzimología , Masculino , Músculo Esquelético/irrigación sanguínea , Ratas , Ratas WistarRESUMEN
We investigated whether hyperbaric oxygen enhances the oxidative metabolic capacity of the skeletal muscle and attenuates adipocyte hypertrophy in type 2 diabetic rats with obesity. Five-week-old male Otsuka Long-Evans Tokushima fatty (OLETF) and Long-Evans Tokushima Otsuka (LETO) rats were used as diabetic animals and nondiabetic controls, respectively, and assigned to control and hyperbaric oxygen groups. Animals in the hyperbaric oxygen group were exposed to an atmospheric pressure of 1.25 with an oxygen concentration of 36% for 3 h daily. The glucose level at 27 weeks of age was significantly higher in OLETF rats than in LETO rats, but the elevation was inhibited in OLETF rats exposed to hyperbaric oxygen. The slow-to-fast fiber transition in the skeletal muscle was observed in OLETF rats, but the shift was inhibited in OLETF rats exposed to hyperbaric oxygen. Additionally, the oxidative enzyme activity of muscle fibers was increased by hyperbaric oxygen. The adipocyte size was larger in OLETF rats than in LETO rats, but hypertrophied adipocytes were not observed in OLETF rats exposed to hyperbaric oxygen. Hyperbaric oxygen enhances glucose and lipid metabolism in the skeletal muscle, indicating that hyperbaric oxygen can prevent elevation of glucose and adipocyte hypertrophy in diabetic rats with obesity.
Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Glucosa/metabolismo , Oxigenoterapia Hiperbárica/métodos , Fibras Musculares Esqueléticas/metabolismo , Obesidad/complicaciones , Obesidad/metabolismo , Animales , Metabolismo Energético , Masculino , Ratas , Ratas Long-EvansRESUMEN
High-load isometric exercise is considered an effective countermeasure against muscle atrophy, but therapeutic electrical stimulation for muscle atrophy is often performed without loading. In the present study, we investigated the combined effectiveness of electrical stimulation and high-load isometric contraction in preventing muscle atrophy induced by hindlimb unloading. Electrical stimulation without loading resulted in slight attenuation of muscle atrophy. Moreover, combining electrical stimulation with high-load isometric contraction enhanced this effect. In electrical stimulation without loading, inhibition of the overexpression of calpain 1, calpain 2, and MuRF-1 mRNA was confirmed. On the other hand, in electrical stimulation with high-load isometric contraction, inhibition of the overexpression of cathepsin L and atrogin-1 mRNA in addition to calpain 1, calpain 2, and MuRF-1 mRNA was confirmed. These findings suggest that the combination of electrical stimulation and high-load isometric contraction is effective as a countermeasure against muscle atrophy.
Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Contracción Isométrica/fisiología , Proteínas Musculares/metabolismo , Atrofia Muscular/metabolismo , Atrofia Muscular/rehabilitación , Animales , Calpaína/metabolismo , Catepsina L/metabolismo , Suspensión Trasera , Masculino , Atrofia Muscular/terapia , Condicionamiento Físico Animal/métodos , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Proteínas Ligasas SKP Cullina F-box/metabolismo , Proteínas de Motivos Tripartitos , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
OBJECTIVE: A total of 105 patients (64 women) who were started on glucocorticoid (GC) treatment for polymyalgia rheumatica (PMR) and/or remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome at Ikeda City Hospital from July 2004 to December 2019 were reviewed (PMR: 81, overlap: 20, pure RS3PE syndrome: 4). Then, 32 cases that had stopped GC and 17 cases that had continued GC for 7.5 years or longer were evaluated (women:men, stopped GC 12:20, continued GC 13:4, respectively) (PMR:overlap:pure RS3PE syndrome, stopped GC 26:6:0, continued GC 14:2:1, respectively). METHODS: The GC continuation rate in all patients was examined using the Kaplan-Meier method. The following were compared between the two groups: age at starting GC; sex; erythrocyte sedimentation rate, C-reactive protein, hemoglobin, ferritin, aspartate aminotransferase, and alanine aminotransferase before starting GC; days from the onset of symptoms to GC initiation; GC maximum dose; GC dose half a year after its start; presence of relapse; and existence of concomitant malignant disease. RESULTS: The GC continuation rate 7.5 years after GC initiation was 52.5%, higher in women (69.2%), than in men (27.1%). The rates then remained unchanged for 15 years. Hemoglobin was high, and relapse was uncommon in the group that stopped GC. There were no differences in other items. CONCLUSION: It is difficult to stop GC therapy for PMR in women in Japan, especially in cases with severe anemia.
RESUMEN
The skeletal muscle is classified into 2 types, slow oxidative or fast glycolytic muscle. For further characterization, we investigated the capillary architecture in slow and fast muscles. The rat soleus and extensor digitorum longus (EDL) muscles were used as representatives of slow and fast muscles, respectively. To investigate capillary density, sections of both types of muscle were stained with alkaline phosphatase; the soleus muscle showed more intense reactivity, indicating that it had a denser capillary structure than the EDL muscle. We then injected fluorescent contrast medium into samples of both muscle types for light and confocal-laser microscopic evaluation. The capillary density and capillary-to-fiber ratio were significantly higher, and the course of the capillaries was more tortuous, in the soleus muscle than in the EDL muscle. Capillary coursed more tortuously in the soleus than in the EDL muscle. Succinate dehydrogenase (SDH) activity, an indicator of mitochondrial oxidative capacity, and vascular endothelial growth factor (VEGF) expression were also significantly higher in the soleus muscle. Thus, we conclude that slow oxidative muscle possess a rich capillary structure to provide demanded oxygen, and VEGF might be involved in the formation and/or maintenance of this highly capillarized architecture.
Asunto(s)
Capilares/anatomía & histología , Microscopía Confocal , Fibras Musculares de Contracción Rápida/citología , Fibras Musculares de Contracción Lenta/citología , Músculo Esquelético/irrigación sanguínea , Fosfatasa Alcalina/metabolismo , Animales , Glucólisis , Imagenología Tridimensional , Masculino , Fibras Musculares de Contracción Rápida/metabolismo , Fibras Musculares de Contracción Lenta/metabolismo , Músculo Esquelético/citología , Músculo Esquelético/metabolismo , Tamaño de los Órganos , Fosforilación Oxidativa , Oxígeno/metabolismo , Ratas , Ratas Wistar , Succinato Deshidrogenasa/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Muscle atrophy is accompanied by a slow-to-fast transformation of the slow muscle, e.g., the soleus muscle, which is characterized by a decrease in the expression of the slow myosin heavy chain (MyHC) isoform. Heat stress before hindlimb unloading, i.e., thermal preconditioning, has been shown to reduce the rate of disuse-induced muscle atrophy. The present study examined whether thermal preconditioning could prevent a slow-to-fast transformation of the MyHC isoform through the induction of heat-shock protein (HSP) 72. Thermally preconditioned rats (Heat + HU) were individually placed in an environmentally controlled heat chamber for 1 h before hindlimb unloading for 2 weeks (HU). Although the mean fiber cross-sectional areas of the soleus muscle decreased in the HU and Heat + HU group, the loss of myofibrillar protein was attenuated in the Heat + HU group. Furthermore, a slow-to-fast transformation of MyHC isoform was inhibited in the Heat + HU group with the overexpression of HSP72. These results indicate that thermal preconditioning before hindlimb unloading attenuates the decrease of the slow MyHC isoform in the soleus muscle. Therefore, thermal preconditioning provides a new approach to prevent disuse-induced fiber type transformation of skeletal muscle.
Asunto(s)
Proteínas del Choque Térmico HSP72/metabolismo , Hipertermia Inducida , Fibras Musculares Esqueléticas/metabolismo , Atrofia Muscular/prevención & control , Cadenas Pesadas de Miosina/metabolismo , Animales , Suspensión Trasera , Calor , Masculino , Contracción Muscular , Fibras Musculares Esqueléticas/citología , Atrofia Muscular/metabolismo , Isoformas de Proteínas/metabolismo , Ratas , Ratas WistarRESUMEN
The enhancement and promotion of health is necessary to maintain the quality of life (QOL) of the aged population in developed nations such as Japan where the number of elderly has been increasing rapidly. For this purpose, low-resistance training using exercise machines ('Power Rehabilitation') has been established as a rehabilitation program. To investigate the individual factors which influence the effects of 'Power Rehabilitation', single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) gene and the ciliary neurotrophic factor (CNTF) gene were analyzed, and the relationship between SNP patterns and the effects of 'Power Rehabilitation' was evaluated. 'Power Rehabilitation' had an effect on the physiological functions involved in the activities of daily life (ADL) rather than muscle strength and size. In addition, certain SNP patterns showed better improvement of parameters associated with the effects of 'Power Rehabilitation' as analyzed by comparison between SNP patterns and factor analysis. Large scale analyses are required to ensure this tendency and to discover individual factors which may help to promote the health and QOL of the aged population.