Muscle & Nerve最新文献

{"title":"Amyotrophic Lateral Sclerosis, the Endocannabinoid System, and Exogenous Cannabinoids: Current State and Clinical Implications.","authors":"Travis T Denton, Gregory T Carter, Megan Goddard, Jeremy Weiss, Douglas L Weeks, Patrick Weydt, Ethan B Russo, Michael D Weiss","doi":"10.1002/mus.28359","DOIUrl":"https://doi.org/10.1002/mus.28359","url":null,"abstract":"<p><p>A unifying mechanistic cause for amyotrophic lateral sclerosis (ALS) remains uncertain. Multiple pathophysiological processes appear to occur simultaneously. Cannabinoids, including delta-9-tetrahydrocannabinol (THC), cannabidiol (CBD), cannabigerol (CBG), and others found in cannabis, and cannabis extracts (CEs), appear to have activity in these pathogenic pathways, which have led to increasing interest in cannabinoids as therapeutic agents for ALS. The use of cannabinoids as a treatment strategy is substantiated by preclinical evidence suggesting a role for the endocannabinoid system (ECS) in ALS and other neurodegenerative disorders. Preclinical data indicate that cannabis and CEs have powerful antioxidative, anti-inflammatory, and neuroprotective effects in the SOD1^G93A mouse model of ALS. The use of CEs in SOD1^G93A murine models has been shown to prolong neuronal cell survival, which leads to delayed onset of the disease state, and slows progression of the disease. Although research in humans remains limited, a few studies suggest that cannabis and CBD, in humans, provide benefits for both motor symptoms, including rigidity, cramps, and fasciculations, and non-motor symptoms including sleep quality, pain, emotional state, quality of life, and depression. There remains a need for further, well-designed clinical trials to validate further the use of an individual cannabinoid, or a combination of cannabinoids, as a disease-modifying therapy for ALS.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143399475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surgical Strategies for Functional Upper Extremity Reconstruction After Spinal Cord Injury.","authors":"Christopher S Crowe, Yusha Katie Liu, Catherine M Curtin, Vincent R Hentz, Scott H Kozin, Ida K Fox, Michael J Berger","doi":"10.1002/mus.28351","DOIUrl":"https://doi.org/10.1002/mus.28351","url":null,"abstract":"<p><p>Spinal cord injuries (SCI) can substantially affect independence and quality of life, particularly by limiting upper extremity function. Surgical reconstruction offers the potential to restore motion in the hand, wrist, and elbow for those with deficits following cervical spinal cord injury. Techniques such as tendon transfer, tenodesis, and arthrodesis-often used in combination-are well-established strategies for enhancing upper extremity function. Nerve transfers have more recently been employed and differ from other procedures in that they are often time sensitive and should be performed before permanent muscle atrophy occurs. A comprehensive preoperative evaluation, including clinical examination and electrodiagnostic assessment, is essential to determine the availability and strength of donor tendons and nerves. The International Classification of Surgery for the Hand in Tetraplegia (ICSHT) system is the most utilized surgical classification for determining muscle that can be used for reconstruction. Based on this classification, prioritization is given to restoring elbow extension, wrist extension, pinch, and grasp. Postoperative rehabilitative therapy balances the need for immobilization while preventing joint stiffness and may also incorporate cortical retraining strategies to activate tendon and nerve transfers. Ultimately, a collaborative, interdisciplinary approach is essential for assessing the injury, determining operative candidacy, selecting the optimal treatment strategy, and providing tailored rehabilitation. This article explores the classification of SCI as it pertains to the upper limb, provides an overview of surgical options, describes the preoperative clinical and electrodiagnostic evaluation process, and discusses reconstructive strategies aimed at improving functional outcomes in individuals with SCI.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143399555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Musculoskeletal mimics for lumbosacral radiculopathy. Part 1: Theoretical considerations.","authors":"Anthony E Chiodo, Shawn P Jorgensen","doi":"10.1002/mus.28280","DOIUrl":"10.1002/mus.28280","url":null,"abstract":"<p><p>The diagnosis of lumbosacral radiculopathy includes the exclusion of common musculoskeletal conditions that can cause similar symptoms. Neurology and physiatry physicians use history taking and physical examination findings to develop a differential diagnosis. Appropriate diagnostic testing is then utilized to narrow down this differential diagnosis to determine a working hypothesis of the cause of a patient's symptoms, leading to a treatment plan. There are stark limitations of patient symptoms and physical examination findings in making the diagnosis of lumbosacral radiculopathy and added value of a combination of symptoms and signs to distinguish patients with lumbosacral radiculopathy from patients with mimic disorders. Diagnostic tests have variable strengths and limitations in helping to confirm this diagnosis, contrasting the high sensitivity and lower specificity of magnetic resonance imaging (MRI) with the high specificity but lower sensitivity of electromyography (EMG). Further complexity is added to the task of making a diagnosis and setting a treatment plan by the fact that these disorders are common and interact with each other; they are present concomitantly in up to 25% of patients presenting for electrodiagnostic evaluation. A companion paper will review common musculoskeletal mimics of lumbosacral radiculopathy and provide tools to anchor testing for those conditions to the traditional neurological evaluation of lumbosacral radiculopathy.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"147-152"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142583831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The BELS questionnaire: A novel screening tool for neurodevelopmental and psychiatric symptoms in pediatric dystrophinopathy.","authors":"Natalie Truba, Seth Sorensen, Rachel Bearden, Brett Haley, Beverly Spray, Kathi Kinnett, Rachel Schrader, Aravindhan Veerapandiyan, Mary K Colvin","doi":"10.1002/mus.28296","DOIUrl":"10.1002/mus.28296","url":null,"abstract":"<p><strong>Introduction/aims: </strong>Pediatric patients with dystrophinopathies [Becker and Duchenne muscular dystrophy (BDMD)] are more likely to have neurodevelopmental and neuropsychiatric conditions. This prospective pilot study tested a novel screening questionnaire developed to identify the common behavioral (B), emotional (E), learning (L), and social (S) difficulties in BDMD.</p><p><strong>Methods: </strong>A total of 45 caregivers of BDMD patients (ages 4-19 years) seen at the Arkansas Children's Hospital Dystrophinopathy Clinic completed the BELS questionnaire during standard clinic visits. To establish external validity, caregivers also completed four well-validated standardized questionnaires assessing overlapping symptoms [Pediatric Symptom Checklist-17 (PSC-17), Colorado Learning Difficulties Questionnaire (CLDQ), the obsessive compulsive disorder (OCD) subscale from the Revised Children's Anxiety and Depression Scale (RCADS), and Barkley Deficits in Executive Functioning Scale (BDEFS)].</p><p><strong>Results: </strong>Caregivers reported high rates of behavioral (>60%), emotional (50%-70%), learning (50%-70%), and social (30%-50%) concerns, even though relatively few patients had clinical diagnoses related to these symptoms. Passive suicidality (i.e., thoughts of death) were also common (22.2%; 10/45 patients). The BELS questionnaire was moderately to highly correlated with total scores on the four well-validated questionnaires (p < .001), and BELS subscales showed specificity. A BELS score of 21 corresponded with the established PSC-17 cutoff.</p><p><strong>Discussion: </strong>The BELS questionnaire shows promise as a screening questionnaire to identify neurobehavioral and neuropsychiatric symptoms common in dystrophinopathy. While BELS cannot currently be used as a standalone measure to make clinical diagnoses, identification of symptoms that warrant further follow-up may improve clinical care and quality of life.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"153-158"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11710981/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142682104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Artifact in Concentric Needle EMG Recordings.","authors":"Sanjeev D Nandedkar, Paul E Barkhaus","doi":"10.1002/mus.28312","DOIUrl":"10.1002/mus.28312","url":null,"abstract":"<p><strong>Introduction/aims: </strong>In healthy subjects, we observed high amplitude motor unit potential (MUP) waveforms that resembled the cannula potential (CP) with a positive sharp wave (PSW)-like waveform. We analyzed the source of this signal, its prevalence, and its effects on the analysis of electromyographic waveforms.</p><p><strong>Methods: </strong>Three channel recordings were performed to explore the contribution of the needle core and cannula to the MUP. In 7 control subjects with no neuromuscular disease, the EMG interference pattern was quantified for the amplitude asymmetry (AASM) of its positive and negative going peaks.</p><p><strong>Results: </strong>The large amplitude MUP resembling a CP with a PSW-type waveform is recorded by the needle core, not the cannula. With a slight change in needle position, its amplitude decreased and the waveform had a normal appearance. Thus, it is an artifact. Such potentials (AASM > 150%) are commonly encountered (frequency 7%) and occur in all muscles and subjects in this study.</p><p><strong>Discussion: </strong>The artifact is an enigma and appears related to the interaction between the needle and muscle fiber(s) similar to that in PSW signals. Failure to recognize these waveforms may result in a false impression of abnormality. AASM calculations can help confirm this artifact in automated analysis algorithms to preclude false positive neurogenic patterns.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"216-222"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142818743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"X-Ray Fluoroscopy-Based Kinematic Analysis of Quadrupedal Locomotion in Slow and Fast Fatigue-Resistant Motor Neuron-Deleted Mice.","authors":"Ayumu Ono, Daijiro Inomata, Lisa Ohgaki, Tenkei Koyama, Akiteru Maeno, Hidemi Misawa, Naomichi Ogihara","doi":"10.1002/mus.28324","DOIUrl":"10.1002/mus.28324","url":null,"abstract":"<p><strong>Introduction/aims: </strong>VAChT-Cre is a transgenic mouse line targeting slow-twitch fatigue-resistant and fast-twitch fatigue-resistant motor neurons that innervate oxidative type I and type IIa muscle fibers. To ablate these neurons, VAChT-Cre mice were crossbred with NSE-DTA mice, leading to the expression of diphtheria toxin A after Cre-mediated excision. The resulting VAChT-Cre;NSE-DTA mice exhibited motor deficits, abnormal locomotion, muscular atrophy, and tremor, making them a useful model for studying motor neuron physiology and pathology. In this study, we conducted a kinematic analysis to examine their abnormal locomotor phenotype.</p><p><strong>Methods: </strong>The quadrupedal walking of VAChT-Cre;NSE-DTA and control mice along a 500 mm acrylic tunnel was analyzed using an X-ray fluoroscopic system. Stride duration, stride length, footfall patterns, and limb and trunk kinematics were quantified and compared between the two groups.</p><p><strong>Results: </strong>Our results demonstrated that VAChT-Cre;NSE-DTA mice walked more slowly than control mice (99.2 ± 43.5 mm/s vs. 120.5 ± 27.0 mm/s) and had a longer cycle duration (0.54 ± 0.19 s vs. 0.41 ± 0.09 s). In addition, the hindlimb was comparatively more flexed during the stance phase, the trunk was more rounded and humpbacked, and the cervix was lower in VAChT-Cre;NSE-DTA mice than in the control mice during locomotion.</p><p><strong>Discussion: </strong>These characteristic differences in the gait kinematics might be attributed to a malfunctioning of the motor units with slow-twitch fatigue-resistant and fast-twitch fatigue-resistant types in VAChT-Cre;NSE-DTA mice. The basic description of the locomotor characteristics of this transgenic mouse line may serve as a basis for future comparative analyses.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"257-264"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11708449/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142847114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Economic Burden of Myasthenia Gravis (MG): A Survey of Affected People and Their Families.","authors":"Kathleen Yoder, Rachael Burris, Sujatha Gurunathan, Glenn Phillips, Kathy Perez, Ali A Habib, Pushpa Narayanaswami","doi":"10.1002/mus.28313","DOIUrl":"10.1002/mus.28313","url":null,"abstract":"<p><strong>Introduction/aims: </strong>Claims-based analyses have demonstrated high medical costs associated with myasthenia gravis (MG). We examined the economic burden of MG from the perspective of affected people and their families.</p><p><strong>Methods: </strong>The Muscular Dystrophy Association developed and conducted an online survey of people with MG and their caregivers between October 26 and December 6, 2021. Major themes were: MG-associated financial decisions, quality of life, employment and direct/indirect costs of diagnosis, healthcare insurance, medical visits, medications/treatments, medical equipment/devices, and caregiving.</p><p><strong>Results: </strong>Eight hundred people with MG and 238 caregivers responding on behalf of a person with MG completed the survey. Most respondents were white (85%) and about half (55%) had received a 4 year college degree or higher education. Respondents indicated that MG impacted their health, recreation, and finances. 70% reported making financial adjustments or seeking financial assistance. Annual out-of-pocket costs (mean, $15,798; median, $7750) were primarily driven by medications, cost to receive a diagnosis, and healthcare insurance premiums. People receiving infusions paid significantly more across all care domains. Demographic disparities were observed, with people of color, women, and those on disability paying significantly more to receive a diagnosis than their counterparts.</p><p><strong>Discussion: </strong>The economic burden on people with MG and their families is substantial, primarily driven by direct costs. There is a need to engage more broadly with the MG community for generalizable information. Respondents were self-selected, which may impact results. The results will be used to educate the public and inform advocacy work, with the goal of improving the lives of people with MG.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"244-251"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142854957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving Perception Threshold Tracking for Rapid Evaluation of Diabetic Peripheral Neuropathy.","authors":"Frederik Østergaard Klit, Vitus Milver Bollerslev, Mette Krabsmark Borbjerg, Johan Røikjer, Niels Ejskjær, Carsten Dahl Mørch","doi":"10.1002/mus.28310","DOIUrl":"10.1002/mus.28310","url":null,"abstract":"<p><strong>Introduction/aims: </strong>Accurate assessment of diabetic peripheral neuropathy (DPN) is essential to prevent further complications, yet current methods have limitations. Perception threshold tracking (PTT) offers promise as a novel approach for rapid evaluation of both large and small fiber dysfunction. To enhance efficiency, this study explores the Psi method compared to the Method of Limits (MoL) in estimating perception thresholds. The aim is to assess agreement, uncertainty, and the number of stimuli required for adequate estimation by each method.</p><p><strong>Methods: </strong>Forty-three participants with diabetes underwent an estimated sural nerve conduction study, quantitative sensory testing, vibration perception threshold testing, and PTT. PTT utilized both patch and pin electrode configurations to activate large and small fibers, respectively. The uncertainty of perception thresholds was estimated as the inverse slope of the psychometric functions.</p><p><strong>Results: </strong>Perception thresholds were significantly higher for the patch electrode (2.5 [2.1-3.0] mA) compared to the pin electrode (0.71 [0.56-0.91] mA; rmANOVA, p < 0.001). Bland-Altman analysis revealed a non-significant 3.3% bias between the methods, but wide limits of agreement (-42%-84%). Uncertainty was lower for the Psi method (0.80 [0.58;1.11] mA) compared to MoL (2.0 [1.2;2.9] mA; rmANOVA, p < 0.005). The Psi method achieved acceptable perception threshold estimation with only 30 stimuli.</p><p><strong>Discussion: </strong>At the group level, the MoL and Psi methods produced similar perception thresholds. However, the Psi method required fewer stimuli and yielded less uncertainty in perception threshold estimation compared to MoL. Future studies should prioritize the Psi method for its efficiency and reliability.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"183-190"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142770661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polyneuropathy With Motor Conduction Block in POEMS.","authors":"Handan Uzunçakmak Uyanık, Fatma Gökçem Yıldız, Bahar Gülmez, Ersin Tan, Çağrı Mesut Temuçin","doi":"10.1002/mus.28302","DOIUrl":"10.1002/mus.28302","url":null,"abstract":"<p><strong>Introduction/aims: </strong>Polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome is a paraneoplastic syndrome due to an underlying plasma cell dyscrasia. Polyneuropathy in POEMS syndrome may present as a subacute or chronic symmetric sensorimotor polyneuropathy, with electrophysiological features suggesting demyelination. Motor conduction block (CB), which is mostly seen in chronic inflammatory demyelinating polyneuropathy (CIDP), is considered an atypical electrophysiological feature in POEMS syndrome. We examined the frequency of motor CB in POEMS syndrome.</p><p><strong>Methods: </strong>Patients with POEMS syndrome from the database of our department who had been examined between August 2017 and December 2022 were included in this study. All of the patients' clinical and electrophysiological data were retrospectively collected and analyzed.</p><p><strong>Results: </strong>We present the data of seven POEMS syndrome patients. Twenty-eight upper extremity motor nerve conduction studies were performed on these patients, and partial CB was detected in seven upper extremity motor nerves (25%) of six of the patients. One patient had motor CB in both the median and ulnar nerves.</p><p><strong>Discussion: </strong>The distinction between POEMS syndrome and CIDP is important since these conditions require different treatments. Motor CB in POEMS may be more common than has been generally believed. Clinicians should consider this when evaluating patients with demyelinating polyneuropathies and be meticulous in identifying CB. Data from much larger numbers of patients are needed.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"159-165"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142687581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cyclosporine A Delays the Terminal Disease Stage in the Tfam KO Mitochondrial Myopathy Mouse Model Without Improving Mitochondrial Energy Production.","authors":"Benjamin Chatel, Isabelle Varlet, Augustin C Ogier, Emilie Pecchi, Monique Bernard, Julien Gondin, Håkan Westerblad, David Bendahan, Charlotte Gineste","doi":"10.1002/mus.28315","DOIUrl":"10.1002/mus.28315","url":null,"abstract":"<p><strong>Introduction and aims: </strong>Mitochondrial myopathies are rare genetic disorders for which no effective treatment exists. We previously showed that the pharmacological cyclophilin inhibitor cyclosporine A (CsA) extends the lifespan of fast-twitch skeletal muscle-specific mitochondrial transcription factor A knockout (Tfam KO) mice, lacking the ability to transcribe mitochondrial DNA and displaying lethal mitochondrial myopathy. Our present aim was to assess whether the positive effect of CsA was associated with improved in vivo mitochondrial energy production.</p><p><strong>Methods: </strong>Mice were treated with CsA for 4 weeks, beginning at 12 weeks (i.e., before the terminal disease phase). Hindlimb plantar flexor muscles were fatigued by 80 contractions (40 Hz, 1.5 s on, 6 s off) while measuring force and energy metabolism using phosphorus-31 magnetic resonance spectroscopy.</p><p><strong>Results: </strong>Force decreased at similar rates in Tfam KO mice with and without the CsA treatment, reaching 50% of the baseline value after ~14 ± 1 contractions, which was faster than in control mice (25 ± 1 contractions). Phosphocreatine (PCr) decreased to ~10% of the control concentration in Tfam KO mice, independent of the treatment, which was larger than the ~20% observed in control mice. The time constant of PCr recovery was higher in untreated Tfam KO than that in control muscle (+100%) and similar in untreated and CsA-treated Tfam KO mice.</p><p><strong>Discussion: </strong>The results do not support improved mitochondrial energy production as a mechanism underlying the prolonged lifespan of Tfam KO mitochondrial myopathy mice treated with CsA. Thus, other mechanisms must be involved, such as the previously observed CsA-mediated protection against excessive mitochondrial Ca²⁺ accumulation.</p>","PeriodicalId":18968,"journal":{"name":"Muscle & Nerve","volume":" ","pages":"265-274"},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11708453/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142876883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}