OBJECTIVE: To observe the effects of antagonistic needling therapy on lower limb spasticity and the muscle morphology of the tibialis anterior and gastrocnemius in patients with stroke. METHODS: A total of 100 patients with post-stroke lower limb spasticity were randomly divided into an antagonistic needling group (50 cases, 1 case dropped out) and a routine acupuncture group (50 cases, 1 case dropped out). Both groups received basic treatment and rehabilitation training. The routine acupuncture group was treated with scalp acupuncture at anterior oblique line of vertex-temporal and vertex lateral line 1, combined with body acupuncture at Jianyu (LI15), Hegu (LI4), Zusanli (ST36), Taichong (LR3), etc. on the affected side, with Quchi (LI11) and Hegu (LI4), Zusanli (ST36) and Fenglong (ST40), Yanglingquan (GB34) and Taichong (LR3) connected to an electroacupuncture device, using disperse wave at 2 Hz of frequency. The antagonistic needling group used the same scalp and upper limb acupoints as the routine acupuncture group, with additional antagonistic needling on the lower limb at Yanglingquan (GB34), Qiuxu (GB40), Jiexi (ST41), and Xuanzhong (GB39) on the affected side, with Quchi (LI11) and Hegu (LI4), Yanglingquan (GB34) and Qiuxu (GB40), Jiexi (ST41), and Xuanzhong (GB39) connected to an electroacupuncture device, using disperse wave at 2 Hz of frequency. Both groups received treatment once daily for 6 consecutive days per course, with a total of 4 courses. The modified Ashworth scale (MAS), Holden functional ambulation classification (FAC), lower limb Fugl-Meyer assessment (FMA), composite spasticity scale (CSS), and musculoskeletal ultrasound parameters (thickness and fiber length of the tibialis anterior and gastrocnemius, and pennation angle of the gastrocnemius on both sides) were evaluated before and after treatment. Clinical efficacy was compared between the two groups. RESULTS: Compared before treatment, the MAS grades and CSS scores were decreased in both groups after treatment (P<0.01), with greater reductions in the antagonistic needling group (P<0.05, P<0.01). FAC grades and FMA scores were increased in both groups after treatment (P<0.01, P<0.05), with greater improvements in the antagonistic needling group (P<0.05). The muscle thickness, fiber length of the tibialis anterior, the muscle thickness, fiber length and pennation angle of the gastrocnemius on the affected side were improved in both groups after treatment (P<0.01), with greater improvements in the antagonistic needling group (P<0.01, P<0.05). On the unaffected side, these parameters were also increased after treatment in both groups (P<0.01, P<0.05), but the antagonistic needling group showed smaller increases than the routine acupuncture group (P<0.01, P<0.05). The total effective rate in the antagonistic needling group was 91.8% (45/49), higher than 81.6% (40/49) in the routine acupuncture group (P<0.05). CONCLUSION Antagonistic needling could effectively reduce spasticity, improve motor function, and enhance muscle structure in patients with post-stroke lower limb spasticity.
Humans ; Male ; Female ; Acupuncture Therapy ; Middle Aged ; Muscle Spasticity/pathology* ; Aged ; Stroke/physiopathology* ; Lower Extremity/physiopathology* ; Acupuncture Points ; Adult ; Muscle, Skeletal/pathology* ; Treatment Outcome

Skeletal muscle dysfunction is a common extrapulmonary comorbidity of chronic obstructive pulmonary disease (COPD) and is associated with decreased quality-of-life and survival in patients. The autophagy lysosome pathway is one of the proteolytic systems that significantly affect skeletal muscle structure and function. Intriguingly, both promoting and inhibiting autophagy have been observed to improve COPD skeletal muscle dysfunction, yet the mechanism is unclear. This paper first reviewed the effects of macroautophagy and mitophagy on the structure and function of skeletal muscle in COPD, and then explored the mechanism of autophagy mediating the dysfunction of skeletal muscle in COPD. The results showed that macroautophagy- and mitophagy-related proteins were significantly increased in COPD skeletal muscle. Promoting macroautophagy in COPD improves myogenesis and replication capacity of muscle satellite cells, while inhibiting macroautophagy in COPD myotubes increases their diameters. Mitophagy helps to maintain mitochondrial homeostasis by removing impaired mitochondria in COPD. Autophagy is a promising target for improving COPD skeletal muscle dysfunction, and further research should be conducted to elucidate the specific mechanisms by which autophagy mediates COPD skeletal muscle dysfunction, with the aim of enhancing our understanding in this field.
Pulmonary Disease, Chronic Obstructive/physiopathology* ; Autophagy/physiology* ; Humans ; Muscle, Skeletal/pathology* ; Mitophagy ; Animals ; Mitochondria/metabolism* ; Lysosomes

The maintenance of skeletal muscle quality involves various signal pathways that interact with each other. Under normal physiological conditions, these intersecting signal pathways regulate and coordinate the hypertrophy and atrophy of skeletal muscles, balancing the protein synthesis and degradation of muscle. When the total rate of protein synthesis exceeds that of protein degradation, the muscle gradually becomes enlarged, while when the total rate of protein synthesis is lower than that of protein degradation, the muscle shrinks. Myocyte atrophy mainly involves two protein degradation pathways, namely ubiquitin-proteasome and autophagy-lysosome. Protein degradation pathway is activated during muscle atrophy, resulting in the loss of muscle mass. Muscle atrophy can occur under various conditions such as malnutrition, aging and cachexia. Skeletal muscle atrophy caused by orthopedic diseases mainly includes disuse muscular atrophy caused by fracture and denervation muscular atrophy. The signal pathways that control and coordinate protein synthesis and degradation in skeletal muscle include insulin-like growth factor 1 (IGF1)-Akt-mammalian target of rapamycin (mTOR), myostatin-activin A-Smad, G protein α inhibitory peptide 2 (Gαi2)-PKC, nuclear factor κB (NF-κB), ectodysplasin A2 receptor (EDA2R)-NF-κB inducing kinase (NIK) and mitogen-activated protein kinase (MAPK) pathways. This paper provides a comprehensive review of the protein degradation pathways in skeletal muscle atrophy and the associated signal pathways regulating protein degradation in muscular atrophy.
Humans ; Muscular Atrophy/etiology* ; Muscle, Skeletal/pathology* ; Signal Transduction ; Animals ; Insulin-Like Growth Factor I/metabolism* ; Myostatin/physiology* ; TOR Serine-Threonine Kinases/metabolism* ; Autophagy/physiology* ; NF-kappa B/metabolism* ; Proteolysis ; Proteasome Endopeptidase Complex/physiology*

The patient was a 55-year-old man who was admitted to hospital with "progressive myalgia and weakness for 4 months, and exacerbated for 1 month". Four months ago, he presented with persistent shoulder girdle myalgia and elevated creatine kinase (CK) at routine physical examination, which fluctuated from 1 271 to 2 963 U/L after discontinuation of statin treatment. Progressive myalgia and weakness worsened seriously to breath-holding and profuse sweating 1 month ago. The patient was post-operative for renal cancer, had previous diabetes mellitus and coronary artery disease medical history, had a stent implanted by percutaneous coronary intervention and was on long-term medication with aspirin, atorvastatin and metoprolol. Neurological examination showed pressure pain in the scapularis and pelvic girdle muscles, and V- grade muscle strength in the proximal extremities. Strongly positive of anti-HMGCR antibody was detected. Muscle magnetic resonance imaging (MRI) T2-weighted image and short time inversion recovery sequences (STIR) showed high signals in the right vastus lateralis and semimembranosus muscles. There was a small amount of myofibrillar degeneration and necrosis, CD4 positive inflammatory cells around the vessels and among myofibrils, MHC-Ⅰ infiltration, and multifocal lamellar deposition of C5b9 in non-necrotic myofibrils of the right quadriceps muscle pathological manifestation. According to the clinical manifestation, imageological change, increased CK, blood specific anti-HMGCR antibody and biopsy pathological immune-mediated evidence, the diagnosis of anti-HMGCR immune-mediated necrotizing myopathy was unequivocal. Methylprednisolone was administrated as 48 mg daily orally, and was reduced to medication discontinuation gradually. The patient's complaint of myalgia and breathlessness completely disappeared after 2 weeks, the weakness relief with no residual clinical symptoms 2 months later. Follow-up to date, there was no myalgia or weakness with slightly increasing CK rechecked. The case was a classical anti-HMGCR-IMNM without swallowing difficulties, joint symptoms, rash, lung symptoms, gastrointestinal symptoms, heart failure and Raynaud's phenomenon. The other clinical characters of the disease included CK as mean levels >10 times of upper limit of normal, active myogenic damage in electromyography, predominant edema and steatosis of gluteus and external rotator groups in T2WI and/or STIR at advanced disease phase except axial muscles. The symptoms may occasionally improve with discontinuation of statins, but glucocorticoids are usually required, and other treatments include a variety of immunosuppressive therapies such as methotrexate, rituximab and intravenous gammaglobulin.
Male ; Humans ; Middle Aged ; Autoantibodies ; Myositis/diagnosis* ; Autoimmune Diseases ; Muscle, Skeletal/pathology* ; Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use* ; Necrosis/pathology* ; Muscular Diseases/drug therapy*

Humans ; Chondrosarcoma, Mesenchymal/pathology* ; Chondrosarcoma/surgery* ; Muscle, Skeletal/pathology* ; Bone Neoplasms/pathology*

Muscle fibres are multinuclear cells, and the cytoplasmic territory where a single myonucleus controls transcriptional activity is called the myonuclear domain (MND). MND size shows flexibility during muscle hypertrophy. The MND ceiling hypothesis states that hypertrophy results in the expansion of MND size to an upper limit or MND ceiling, beyond which additional myonuclei via activation of satellite cells are required to support further growth. However, the debate about the MND ceiling hypothesis is far from settled, and various studies show conflicting results about the existence or otherwise of MND ceiling in hypertrophy. The aim of this review is to summarise the literature about the MND ceiling in various settings of hypertrophy and discuss the possible factors contributing to a discrepancy in the literature. We conclude by describing the physiological and clinical significance of the MND ceiling limit in the muscle adaptation process in various physiological and pathological conditions.
Humans ; Muscle Fibers, Skeletal/physiology* ; Hypertrophy/pathology* ; Muscle, Skeletal

OBJECTIVES: To summarize the skeletal muscle magnetic resonance imaging (MRI) features of the lower limbs in common subtypes of muscular dystrophy (MD) and the experience in the application of MRI in the diagnosis of MD. METHODS: A total of 48 children with MD who were diagnosed by genetic testing were enrolled as subjects. The muscle MRI features of the lower limbs were analyzed. Cumulative fatty infiltration score was calculated for each subtype, and the correlation of cumulative fatty infiltration score with clinical indices was analyzed for Duchenne muscular dystrophy (DMD). RESULTS: DMD was characterized by the involvement of the gluteus maximus and the adductor magnus. Becker muscular dystrophy was characterized by the involvement of the vastus lateralis muscle. Limb-girdle muscular dystrophy was characterized by the involvement of the adductor magnus, the vastus intermedius, the vastus medialis, and the vastus lateralis muscle. For DMD, the cumulative fatty infiltration score of the lower limb muscles was significantly correlated with age, course of the disease, muscle strength, and motor function (P<0.05), while it was not significantly correlated with the serum creatine kinase level (P>0.05). CONCLUSIONS Different subtypes of MD have different MRI manifestations, and MRI may help with the diagnosis and assessment of MD.
Child ; Humans ; Muscular Dystrophy, Duchenne/diagnostic imaging* ; Muscular Dystrophies, Limb-Girdle/pathology* ; Muscle, Skeletal/diagnostic imaging* ; Magnetic Resonance Imaging/methods* ; Thigh/pathology*

As an important exercise and energy metabolism organ of the human body, the normal maintenance of skeletal muscle mass is essential for the body to perform normal physiological functions. The autophagy-lysosome (AL) pathway is a physiological or pathological mechanism that is ubiquitous in normal and diseased cells. It plays a key role in the maintaining of protein balance, removing damaged organelles, and the stability of internal environment. The smooth progress of the autophagy process needs to go through multiple steps, which are completed under the coordinated action of multiple factors. Autophagy maintains the muscle homeostasis of a healthy body by removing cell components such as damaged myofibrils and isolated cytoplasmic proteins. Autophagy could also provide the initial energy required for cell proliferation, promote muscle regeneration and remodeling after injury. At the same time, autophagy disorder is also an important cause of age-related skeletal muscle atrophy. Autophagy could affect the response of skeletal muscle to exercise, and increasing the level of basic autophagy is beneficial to improve the adaptive response of skeletal muscle to exercise. This article summarizes the role and pathways of autophagy in the maintenance of skeletal muscle quality, in order to provide effective rehabilitation strategies for clinical prevention and treatment of muscle atrophy.
Autophagy/physiology* ; Exercise/physiology* ; Humans ; Muscle, Skeletal/pathology* ; Muscular Atrophy/pathology* ; Signal Transduction

Animals ; Hindlimb ; Male ; Mice ; Mice, Inbred C57BL ; Muscle Fibers, Skeletal ; Muscle, Skeletal/pathology* ; Muscular Atrophy

To explore the value of conventional ultrasound combined with shear-wave elastography in the quantitative evaluation of sciatic nerve crush injury in rabbit models. Forty healthy male New Zealand white rabbits were randomly divided into four groups (=10 in each group):three crush injury (CI) groups (2,4,and 8 weeks after crush) and control group (without injury). The thickness and stiffness of the crushed sciatic nerves and denervated triceps surae muscles were measured at different time points and compared with histopathologic parameters. Inter-reader variability was assessed with intraclass correlation coefficients. Compared with the control group,the inner diameters of the sciatic nerves significantly increased in the 2-week CI group [(1.65±0.34) mm (0.97±0.15) mm,=0.00] but recovered to the nearly normal level in the 8-week CI group [(1.12±0.18) mm (0.97±0.15) mm,=0.06];however,compared with control group [(8.75±1.02)kPa],the elastic modulus of the nerves increased significantly in all the CI groups [2-week:(14.77±2.53) kPa;4-week:(19.12±3.46) kPa;and 8-week:(28.39±5.26) kPa;all =0.00];pathologically,massive hyperplasia of collagen fibers were found in the nerve tissues. The thickness of denervated triceps surae muscle decreased gradually,and the elastic modulus decreased 2 weeks after injury but increased gradually in the following 6 weeks;pathologically,massive hyperplasia of collagen fibers and adipocytes infiltration were visible,along with decreased muscle wet-weight ratio and muscle fiber cross-sectional area. The inter-reader agreements were good. Conventional ultrasound combined with shear-wave elastography is feasible for the quantitative evaluation of the morphological and mechanical properties of crushed nerves and denervated muscles.
Animals ; Crush Injuries ; diagnostic imaging ; Elastic Modulus ; Elasticity Imaging Techniques ; Male ; Muscle, Skeletal ; innervation ; pathology ; Rabbits ; Random Allocation ; Sciatic Nerve ; injuries ; Ultrasonography