Microscopic changes in the spinal extensor musculature in patients experiencing chronic spinal pain: Protocol for a systematic review

Introduction Chronic spinal pain (CSP) is the most common musculoskeletal disorder and is a leading cause of disability as per the Global Burden of Diseases. Previous reviews of microscopic changes in the spinal extensor muscles of people with CSP have focused on the lumbar region only and the results have been inconclusive. Therefore, in this protocol, we aim to assess microscopic changes in the extensor muscles of all spinal regions, investigating regionally specific changes in muscle fibre types of the spinal extensor muscles in patients with non-specific CSP. Methods/analysis This protocol was designed using Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines. Searches will use the following databases: MEDLINE, Embase, PubMed, CINAHL Plus and Web of Science along with relevant grey literature searches. Two reviewers will conduct the searches, perform data extraction, apply inclusion criteria and conduct risk of bias assessment using Newcastle-Ottawa Scale. Data will be synthesised and analysed independently. If there is sufficient homogeneity, then meta-analysis will be conducted by the reviewers jointly. If not, meta-synthesis or narrative reporting will be performed. The quality of the evidence will be assessed using Grading of Recommendations, Assessment, Development and Evaluation (GRADE) guidelines. Ethics and dissemination The results of this study will be submitted for publication to a peer-reviewed journal and will be presented at conferences. Ethical approval for this systematic review was not required due to no patient data being collated

Skeletal muscle transcriptional coactivator PGC-1alpha mediates mitochondrial, but not metabolic, changes during calorie restriction

Calorie restriction (CR) is a dietary intervention that extends lifespan and healthspan in a variety of organisms. CR improves mitochondrial energy production, fuel oxidation, and reactive oxygen species (ROS) scavenging in skeletal muscle and other tissues, and these processes are thought to be critical to the benefits of CR. PGC-1alpha is a transcriptional coactivator that regulates mitochondrial function and is induced by CR. Consequently, many of the mitochondrial and metabolic benefits of CR are attributed to increased PGC-1alpha activity. To test this model, we examined the metabolic and mitochondrial response to CR in mice lacking skeletal muscle PGC-1alpha (MKO). Surprisingly, MKO mice demonstrated a normal improvement in glucose homeostasis in response to CR, indicating that skeletal muscle PGC-1alpha is dispensable for the whole-body benefits of CR. In contrast, gene expression profiling and electron microscopy (EM) demonstrated that PGC-1alpha is required for the full CR-induced increases in mitochondrial gene expression and mitochondrial density in skeletal muscle. These results demonstrate that PGC-1alpha is a major regulator of the mitochondrial response to CR in skeletal muscle, but surprisingly show that neither PGC-1alpha nor mitochondrial biogenesis in skeletal muscle are required for the whole-body metabolic benefits of CR

Tibialis anterior muscle hernia : a case of chronic, dull pain and swelling in leg diagnosed by dynamic ultrasonography

BACKGROUND: Symptomatic muscle hernias are not uncommon in the lower extremities and are a rare cause of chronic leg pain. They are most commonly seen in the tibialis anterior muscle, occurring through fascial defects, usually after trauma. There are about 200 cases of muscle hernias described in the literature. The diagnosis is challenging as most of the patients present with non-specific chronic leg pain. Dynamic muscle ultrasonography at rest and at stress is often used for the diagnosis. CASE REPORT: We describe a case of tibialis anterior muscle hernia presenting with persistent dull pain and swelling along the anterior aspect of the leg on straining the leg muscles. Dynamic ultrasonography was performed, which showed a defect in the fascial sheath of the muscle through which the tibialis anterior muscle herniated and produced a focal bulge along the anterior aspect of the leg. Based upon physical examination and dynamic ultrasonographic findings, a diagnosis of tibialis anterior muscle hernia was made. CONCLUSIONS: Tibialis anterior muscle hernia is a rare diagnosis and should be included in the differential diagnosis in a patient with chronic leg pain and swelling. Dynamic ultrasound is crucial in confirming the diagnosis and should be done on straining the muscles of the affected limb

Frontalis Muscle Strength Calculation Based On 3D Image Using Gray Level Co-occurrence Matrix (GLCM) and Confidence Interval

One of the effects of the disorders of nervus VII (n. Facialis) is the damage of facial muscle. The research is needed in order to detect or as the therapies aids on the damage of the VII nerve by measuring the strength of maximum contraction, to help a therapy or detect the damage which caused by the decreasing of the VII nerve function. These measurement is taken from the difference on myofibrin when the contractions, because when the contraction happen, the myofibrin will distend and the difference can be detected as the strength of contraction. From the result of the comparison, EMG with the test result is the shift muscle movement amount of 1.367 up to 4.460. The mean value of rest muscle is in the range of 0.635 with interval at+0.463, on the move muscles the mean value of the muscle moving is in the range of 3,563 with interval at+1,069. This test is linear with the data EMG

Muscle Regeneration and Function in Sports: A Focus on Vitamin D

Muscle is one of the main targets for the biological effects of vitamin D. This hormone modulates several functions of skeletal muscles, from development to tissue repair after injury, through genomic and non-genomic mechanisms. Vitamin D deficiency and supplementation seem to significantly affect muscle strength in different populations, including athletes, although optimal serum 25(OH)D3 level for sport performance has not been defined so far. Additionally, vitamin D de- ficiency results in myopathy characterized by fast-twitch fiber atrophy, fatty infiltration, and fibrosis. However, less is known about regenerative effects of vitamin D supplementation after sport-related muscle injuries. Vitamin D receptor (VDR) is particularly expressed in the embryonic mesoderm during intrauterine life and in satellite cells at all stages of life for recovery of the skeletal muscle after injury. Vitamin D supplementation enhances muscle differentiation, growth, and regeneration by increasing the expression of myogenic factors in satellite cells. The objective of this narrative review is to describe the role of vitamin D in sport-related muscle injury and tissue regeneration

Quantitative reduction of RyR1 protein caused by a single-allele frameshift mutation in RYR1 ex36 impairs the strength of adult skeletal muscle fibres

Here we characterized a mouse model knocked-in for a frameshift mutation in RYR1 exon 36 (p.Gln1970fsX16) that is isogenic to that identified in one parent of a severely affected patient with recessively inherited multiminicore disease. This individual carrying the RYR1 frameshifting mutation complained of mild muscle weakness and fatigability. Analysis of the RyR1 protein content in a muscle biopsy from this individual showed a content of only 20% of that present in a control individual. The biochemical and physiological characteristics of skeletal muscles from RyR1Q1970fsX16 heterozygous mice recapitulates that of the heterozygous parent. RyR1 protein content in the muscles of mutant mice reached 38% and 58% of that present in total muscle homogenates of fast and slow muscles from wild-type (WT) littermates. The decrease of RyR1 protein content in total homogenates is not accompanied by a decrease of Cav1.1 content, whereby the Cav1.1/RyR1 stoichiometry ratio in skeletal muscles from RyR1Q1970fsX16 heterozygous mice is lower compared to that from WT mice. Electron microscopy (EM) revealed a 36% reduction in the number/area of calcium release units accompanied by a 2.5-fold increase of dyads (triads that have lost one junctional sarcoplasmic reticulum element); both results suggest a reduction of the RyR1 arrays. Compared to WT, muscle strength and depolarization-induced calcium transients in RyR1Q1970fsX16 heterozygous mice muscles were decreased by 20% and 15%, respectively. The RyR1Q1970fsX16 mouse model provides mechanistic insight concerning the phenotype of the parent carrying the RYR1 ex36 mutation and suggests that in skeletal muscle fibres there is a functional reserve of RyR1

Manduca sexta as an Animal Model of Muscle Aging

Aging has a multisystemic effect on an organism’s functional physiology and quality of life. One such effect is the progressive loss of muscle mass, strength, and function, known as sarcopenia. A thorough investigation to the multiple factors that contribute to sarcopenia is required. Models are used to dissect the mechanistic understanding of the muscle aging process. Manduca sexta is emerging as a novel and complementary muscle aging model because their flight muscles are metabolically and functionally similar to vertebrate skeletal muscle. Manduca sexta is already a prominent invertebrate model organism in neurobiology, immunology, developmental research, and flight mechanics because of its short life span, economic benefits, feasible handling, and extensive molecular toolkit for future research and therapeutics. In this review, I analyze the research showing that Manduca sexta is an emerging and ideal invertebrate muscle aging model that enhances the comparative approach for muscle aging research