Search Results (502)

Background: Duchenne Muscular Dystrophy (DMD) is an X-linked recessive neuromuscular disorder that is characterized by progressive muscle weakness, musculoskeletal limitations, and pulmonary involvement, with cardiomyopathy and cardiovascular complications being a primary cause of morbidity and mortality. With advances in respiratory care, cardiac involvement has become the leading cause of death. There is growing interest in systemic inflammatory indices as potential predictors of cardiovascular involvement. This study aimed to evaluate the prognostic value of inflammatory markers—neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic inflammatory response index (SIRI), systemic immune-inflammation index (SII), and pan-immune inflammation value (PIV)—in children with DMD and to explore their association with cardiac findings. Methods: In this retrospective study, 25 male patients diagnosed with DMD and 25 age-matched healthy male controls were evaluated between January 2021 and July 2024. Demographic and clinical data, hematologic and biochemical parameters, and inflammatory indices were recorded. Cardiovascular involvement was assessed using electrocardiography (ECG) and transthoracic echocardiography (TTE). Group comparisons were performed using independent t-tests, while ROC and Pearson correlation analyses were used for diagnostic performance and associations. Results: Pathological Q waves were the most frequent ECG abnormality (24%), and 16% of patients had echocardiographic abnormalities. While most systemic inflammatory indices (NLR, MLR, SIRI, SII, PIV) did not significantly distinguish cardiovascular involvement, PLR demonstrated a strong positive correlation with Pro-BNP levels (r = 0.86, p < 0.05), suggesting a potential link between systemic inflammation and subclinical cardiac stress. Conclusions: Although the overall diagnostic utility of inflammatory indices in predicting cardiovascular complications in DMD was limited, PLR showed a correlation with Pro-BNP in our cohort. However, given the small sample size and limited number of patients with ventricular dysfunction, this finding should be interpreted with caution. PLR may warrant further investigation as a potential marker of cardiovascular involvement in DMD, but larger prospective studies are needed to validate its clinical significance. Full article

Duchenne muscular dystrophy (DMD) is a lethal inherited muscle disease caused by mutations in the DMD gene, and the development of gene therapies targeting DMD is rapidly progressing. Patient-derived induced pluripotent stem cells and animal models that mimic patient-specific mutations have significantly contributed to the advancement of precision medicine based on individual genetic profiles. Currently, no approved disease-specific therapy exists for DMD cardiomyopathy, which remains one of the leading causes of death in DMD patients. Therefore, the development of effective cardiac therapies represents a critical milestone in DMD research. In this review, we provide an overview of essential cellular and animal models used in DMD research, with a specific focus on the heart. We describe their key characteristics, advantages, and limitations. It is considered that a comprehensive and strategic integration of these models—based on a clear understanding of their respective strengths and weaknesses—will be important for advancing the development and clinical application of targeted therapies for DMD cardiomyopathy. Full article

Nuclear processes are fundamental to the regulation of cellular, tissue, and organismal function, especially in complex multicellular systems. Central to these processes are lamins and lamin-associated proteins, which contribute to nuclear structure, gene expression, and chromatin organization. The discovery that mutations in genes coding for lamins and lamina-associated proteins give rise to rare disorders—collectively called laminopathies—has intensified interest in this field among cell biologists and medical scientists. While many practical and clinically relevant questions about phenotype development and potential treatments require mammalian models, key molecular mechanisms and interactions have also been effectively studied in both vertebrate and invertebrate systems. This review focuses on a discussion of Drosophila lamins, their major properties, functions, interactions and post-translational modifications, with comparison to mammalian lamins, and a discussion of the value of fly models in studies of lamins in muscle tissue development and function in comparison to mammalian lamin B-type and A/C-type. In this paper, we have discussed the overall impact of lamin Dm and lamin C level manipulations on overall phenotype, especially on larval and adult muscles. We have thoroughly discussed the conclusions, which may have been drawn from experiments with overexpression of lamin C mutants mimicking lamin A laminopathy mutations. We have presented and discussed the suggestion that the mechanisms underlying Drosophila muscle phenotype development are similar not only to human dystrophic laminopathies but also to classical human muscular dystrophies such as Duchenne muscular dystrophy and Hutchison–Gilford Progeria syndrome. We suggest that the activation of the stress response contributes to the laminopathic phenotype detected in Drosophila. Finely, this review discusses in depth the lamin Dm and lamin C interactomes, discrepancies between String-based interactome networks, and our map of interactomes based on manual verification of experimental data on Drosophila lamin interactions. Full article

Monocytes/macrophages promote the repair of acutely injured muscle while contributing to dystrophic changes in chronically injured muscle in Duchenne muscular dystrophy (DMD) patients and animal models including mdx and mdx^5cv mice. To elucidate the molecular mechanisms underlying this functional difference, we compared the transcriptomes of intramuscular monocytes/macrophages from wild-typed (WT) uninjured muscles, WT acutely injured muscles, and mdx^5cv dystrophic muscles, using single cell-based RNA sequencing (scRNA-seq) analysis. Our study identified multiple transcriptomically diverse monocyte/macrophage subclusters, which appear to be induced by the intramuscular microenvironment. They expressed feature genes differentially involved in muscle inflammation, regeneration, and extracellular matrix (ECM) remodeling, but none of them conform to strict M1 or M2 activation. The Gpnmb⁺Spp1⁺ macrophage subcluster, an injury-associated subcluster that features the signature genes of reported scar-associated macrophages (SAMs) involved in ECM remodeling and fibrosis, is present transiently in acutely injured muscle and persistently in chronically injured dystrophic muscle, along with the persistence of monocytes. Our findings suggest that the persistent monocyte/macrophage infiltration and activation induced by continuous injury may underlie the pathogenic roles of macrophages in mdx^5cv muscles. Controlling muscle injury and subsequent macrophage infiltration and activation may be important to the treatment of DMD. Full article

Background: The onset of cardiomyopathy in Duchenne muscular dystrophy (DMD) is insidious and poorly defined. We proposed integrated wall stress (iWS) as a marker of total left ventricular (LV) workload and tested whether the increased iWS represents early DMD cardiomyopathy. Methods: Peak systolic wall stress (PS-WS) was calculated in M-mode echocardiography with simultaneous blood pressure measurement. iWS was defined as a product of PS-WS and heart rate (HR) divided by 60 (=PS-WS/RR interval). We measured iWS in normal controls (CTRL), DMD with normal LV shortening fraction (%LVSF ≥ 30%) (DMD-A), and DMD with decreased %LVSF (<30%) (DMD-B). Results: 40 CTRL and 79 DMD patients were studied. Despite comparable %LVSF, both HR and iWS were significantly higher in DMD-A (n = 50) than in CTRL (p < 0.0001). iWS was significantly higher in DMD-B (n = 29) than in DMD-A (p < 0.0001) despite comparable HR. PS-WS was significantly higher in DMD-A than in CTRL and higher in DMD-B than in DMD-A, suggesting high HR is not a sole determinant of increased iWS in DMD-A compared with CTRL. In a longitudinal study in 35 DMD patients over 4.0 ± 2.0 years, iWS showed significant increase (p = 0.0062) alongside a significant decline in %LVSF (p < 0.0001). Conclusions: iWS significantly increased in DMD before %LVSF declined. The progressive increase of iWS in DMD is initially associated with increased HR and then with increased PS-WS. iWS may serve as a useful echocardiographic marker in identifying preclinical DMD cardiomyopathy. Full article

Duchenne muscular dystrophy (DMD) is a severe X-linked disorder characterized by progressive muscle degeneration due to mutations in the dystrophin gene. Despite major advancements in understanding its pathophysiology, there is still no curative treatment. This review provides an up-to-date overview of current and emerging therapeutic approaches—including antisense oligonucleotides, gene therapy, gene editing, corticosteroids, and histone deacetylases(HDAC) inhibitors—aimed at restoring dystrophin expression or mitigating disease progression. Special emphasis is placed on the importance of early diagnosis, the utility of genetic screening, and the innovations in pre-and post-natal testing. As the field advances toward personalized medicine, the integration of precision therapies with cutting-edge diagnostic technologies promises to improve both prognosis and quality of life for individuals with DMD. Full article

The complexity of RNA metabolism has become crucial in neuromuscular diseases, especially for Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). Our goal was to search for possible pathways that differ between the two diseases, in which DMD develops a severe phenotype compared to BMD. In this work, we aimed to evaluate the transcriptomic profile in skeletal muscle biopsies derived from patients with either DMD or BMD. We collected RNA obtained from pediatric patients with DMD (n = 12) and with BMD (n = 6). Compared to patients with BMD, patients with DMD showed a particular activation of genes involved in collagen synthesis, extracellular matrix organization, and Oncostatin M-dependent pathways, important for fibrotic processes. This suggests that a more severe phenotype in patients with DMD compared to those with BMD may be due to greater deregulation of these pathways, reflecting the clinical picture of patients observed. Our results allowed us to highlight the molecular differences between the two phenotypic groups, shedding light on the pathways that make Duchenne dystrophy more severe than its counterpart does. This study provides preliminary insights into the difference in gene expression between the two groups and lays the basis for the identification of possible mechanisms that differentiate between the two diseases. Full article

Targeting fibrosis in Duchenne muscular dystrophy (DMD)-associated cardiomyopathy is a critical outstanding clinical issue, as cardiac failure remains a leading cause of death despite advances in supportive care. This study evaluates the therapeutic efficacy of CSPG4-targeted chimeric antigen receptor (CAR) T cells in reducing cardiac fibrosis and improving heart function in a preclinical model of the disease. DMD is a progressive genetic disorder characterized by degeneration of skeletal and cardiac muscle. Cardiomyopathy, driven by fibrosis and chronic inflammation, is a leading contributor to mortality in affected patients. Proteoglycans such as CSPG4, critical regulators of extracellular matrix dynamics, are markedly overexpressed in dystrophic hearts and promote pathological remodeling. Current treatments do not adequately target the fibrotic and inflammatory processes underlying cardiac dysfunction. CSPG4-specific CAR-T cells were engineered and administered to dystrophic mice. Therapeutic efficacy was assessed through histological, molecular, and echocardiographic analyses evaluating cardiac fibrosis, inflammation, innervation, and overall function. Treatment with CSPG4 CAR-T cells preserved myocardial integrity, improved cardiac performance, and reduced both fibrosis and inflammatory markers. The therapy also restored cardiac innervation, indicating a reversal of neural remodeling commonly seen in muscular dystrophy-related cardiomyopathy. CSPG4-targeted CAR-T therapy offers a novel, cell-based strategy to mitigate cardiac remodeling in dystrophic hearts. By addressing core fibrotic and inflammatory drivers of disease, this approach represents a significant advancement in the development of precision immune therapies for muscular dystrophies and cardiovascular conditions. Full article

Background: Duchenne muscular dystrophy (DMD), which affects 1 in 3500 to 5000 newborn boys worldwide, is characterized by progressive skeletal muscle weakness and degeneration. The reduced muscle regeneration capacity presented by patients is associated with increased fibrosis. Satellite cells (SCs) are skeletal muscle stem cells that play an important role in adult muscle maintenance and regeneration. The absence or mutation of dystrophin in DMD is hypothesized to impair SC asymmetric division, leading to cell cycle arrest. Methods: To overcome the limited availability of biopsies from DMD patients, we used our 3D skeletal muscle organoid (SMO) system, which delivers a stable population of myogenic progenitors (MPs) in dormant, activated, and committed stages, to perform SMO cultures using three DMD patient-derived iPSC lines. Results: The results of scRNA-seq analysis of three DMD SMO cultures versus two healthy, non-isogenic, SMO cultures indicate reduced MP populations with constant activation and differentiation, trending toward embryonic and immature myotubes. Mapping our data onto the human myogenic reference atlas, together with primary SC scRNA-seq data, indicated a more immature developmental stage of DMD organoid-derived MPs. DMD fibro-adipogenic progenitors (FAPs) appear to be activated in SMOs. Conclusions: Our organoid system provides a promising model for studying muscular dystrophies in vitro, especially in the case of early developmental onset, and a methodology for overcoming the bottleneck of limited patient material for skeletal muscle disease modeling. Full article

Dilated cardiomyopathy affects greater than 1 in 2500 patients worldwide, including those with the neuromuscular disorder Duchenne muscular dystrophy (DMD). While inflammation within skeletal muscle is strongly associated with DMD pathology, the key biomarkers for inflammation and possible targets for therapy within cardiac tissue in DMD-associated dilated cardiomyopathy remain to be identified. One such potential target is the myocardial ghrelin-growth hormone secretagogue receptor (GHSR) system, which is associated with cardiomyocyte survival and inhibition of inflammation. We sought to determine alterations in myocardial GHSR together with markers of cardiac inflammation using mdx:utrn^−/− mice as a model for DMD-associated dilated cardiomyopathy. With traditional histopathology, we determined that the pathology of DMD in mdx:utrn^−/− mice was characterized by disruption of myofiber organization, lymphocytic infiltration, and extensive cardiomyocyte vacuolization and necrosis surrounding areas of fibrosis in the left ventricular wall and apex. Using a fluorescent ghrelin analog, Cy5-ghrelin (1–19), to visualize GHSR with fluorescence confocal microscopy, we demonstrate that GHSR is elevated in mdx/utrn^−/− myocardial tissues and correlates strongly with both F4-80 (activated macrophages) and IL-6 (pro-inflammatory cytokine), and negatively with cardiac function. We also show that GHSR can be visualized in pro-inflammatory macrophages, suggesting a direct role for GHSR in the inflammatory progression of DMD. Full article

Background: Duchenne muscular dystrophy (DMD) is a severe X-linked neuromuscular disorder caused by mutations in the DMD gene, leading to progressive muscle degeneration, loss of ambulation, and multi-systemic complications. Beyond its impact on mobility, DMD is associated with significant endocrine and metabolic dysfunctions that develop over time. Objective: To provide a comprehensive analysis of growth disturbances, endocrine dysfunctions, and metabolic complications in DMD including bone metabolism, considering the underlying mechanisms, clinical implications, and management strategies for daily clinical guidance. Methods: In this narrative review, an evaluation of the literature was conducted by searching the Medline database via the PubMed, Scopus, and Web of Science interfaces. Results: Growth retardation is a hallmark feature of DMD, with patients exhibiting significantly shorter stature compared to their healthy peers. This is exacerbated by long-term glucocorticoid therapy, which disrupts the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis and delays puberty. Obesity prevalence follows a biphasic trend, with increased risk in early disease stages due to reduced mobility and corticosteroid use, followed by a decline in body mass index (BMI) in later stages due to muscle wasting. Metabolic complications, including insulin resistance, altered lipid metabolism, and hepatic steatosis, further characterize disease burden. Osteoporosis and increased fracture risk, primarily due to reduced mechanical loading and glucocorticoid-induced bone resorption, are major concerns, needing early screening and intervention. The RANK/RANKL/OPG signaling pathway has emerged as a critical factor in bone deterioration, providing potential therapeutic targets for improving skeletal health. Conclusions: Growth and endocrine disorders in DMD are complex and multifactorial, requiring proactive monitoring and early intervention. Addressing these issues requires a multidisciplinary approach integrating endocrine, nutritional, and bone health management. Further research is essential to refine treatment strategies that mitigate growth and metabolic disturbances while preserving overall patient well-being. Full article

Duchenne muscular dystrophy (DMD) is a severe inherited muscle-wasting disorder that is associated with severe morbidity and mortality globally. Current treatment options have improved the quality of life of patients, but these treatments are only palliative. There is a need for more DMD treatment options. Antisense oligonucleotide (ASO) therapies have emerged as a promising personalized treatment option for patient groups that possess specific mutations. A subset of these therapies can skip over frame-disrupting exons in the DMD gene and can partially restore dystrophin production for individuals with DMD. One novel exon skipping therapy currently being investigated is brogidirsen, an exon 44 that targets ASO using a novel dual-targeting approach. This article will provide an overview of brogidirsen’s history and current clinical trial developments. It will summarize how this investigational therapy compares with other pre-clinical and clinical trial-stage ASO therapies targeting exon 44. Current advances and challenges faced by RNA-based therapies will also be discussed. Overall, brogidirsen is a promising potential addition to existing DMD treatment options, with its clinical trial results showing expression levels above that of the maximum amount of dystrophin expression achieved by current FDA- and EMA-approved exon-skipping DMD therapies. Further research will be needed to determine its overall efficacy and ability to overcome the known limitations faced by other existing ASO therapies. Full article

Background/Objectives: Duchenne muscular dystrophy (DMD) is often discussed in the literature with regard to physical impairments. This narrative review aims to show that living with DMD involves psychological, psychosocial, and cognitive aspects in addition to the well-known physical complications. Methods: Firstly, this review examines the main cognitive functions affecting subjects with DMD and the possible role of dystrophin gene mutations on the central nervous system. Secondly, it analyzes the comorbidity between DMD, neurodevelopmental disorders (autism spectrum disorders, attention-deficit/hyperactivity disorder, obsessive–compulsive disorder) and psychopathological traits (anxiety and/or depressive symptoms). Finally, the review addresses the relatively sparse literature investigating the positive aspects associated with the experience of DMD, like psychosocial resources, resilience, subjective well-being, positive individual and social functioning, and social support. Results: DMD has a significant impact on cognitive areas, probably due to dystrophin deficiency in the brain. The prevalence of neurodevelopmental comorbidities and psychopathological symptoms is also higher in people with DMD than in the general population. Despite these challenges, emerging studies highlight the role of psychosocial and environmental resources, including resilience and supportive social relations, in promoting a good quality of life and successful adaptation to disease progression. Conclusions: Early recognition of the above difficulties and strengths could ensure better care and promote an overall better quality of life for people with DMD and their families, physically, psychologically, and socially. Preclinical and clinical research is moving in the direction of finding new therapies, treatments, and psychosocial interventions to pursue these goals. Full article

Duchenne muscular dystrophy (DMD) manifests as a hereditary condition that diminishes muscular strength through the progressive degeneration of structural muscle tissue, which is brought about by deficiencies in the dystrophin protein required for the integrity of muscle cells. DMD is among four different types of dystrophinopathy disorders. Current studies have established that long non-coding RNAs (lncRNAs) play a significant role in determining the trajectory and overall prognosis of chronic musculoskeletal conditions. LncRNAs are different in terms of their lengths, production mechanisms, and operational modes, but they do not produce proteins, as their primary activity is the regulation of gene expression. This research synthesizes current literature on the role of lncRNAs in the regulation of myogenesis with a specific focus on certain lncRNAs leading to DMD increments or suppressing muscle biological functions. LncRNAs modulate skeletal myogenesis gene expression, yet pathological lncRNA function is linked to various muscular diseases. Some lncRNAs directly control genes or indirectly control miRNAs with positive or negative effects on muscle cells or the development of DMD. The research findings have significantly advanced our knowledge about the regulatory function of lncRNAs on muscle growth and regeneration processes and DMD diseases. Full article

Recent studies on myogenic satellite cells (SCs) in Duchenne muscular dystrophy (DMD) documented altered division capacities and impaired regeneration potential of SCs in DMD patients and animal models. It remains unknown, however, if SC-intrinsic effects trigger these deficiencies at pre-contractile stages of myogenesis rather than resulting from the pathologic environment. In this study, we isolated SCs from a porcine DMD model and age-matched wild-type (WT) piglets for comprehensive analysis. Using immunofluorescence, differentiation assays, traction force microscopy (TFM), RNA-seq, and label-free proteomic measurements, SCs behavior was characterized, and molecular changes were investigated. TFM revealed significantly higher average traction forces in DMD than WT SCs (90.4 ± 10.5 Pa vs. 66.9 ± 8.9 Pa; p = 0.0018). We identified 1390 differentially expressed genes and 1261 proteins with altered abundance in DMD vs. WT SCs. Dysregulated pathways uncovered by gene ontology (GO) enrichment analysis included sarcomere organization, focal adhesion, and response to hypoxia. Multi-omics factor analysis (MOFA) integrating transcriptomic and proteomic data, identified five factors accounting for the observed variance with an overall higher contribution of the transcriptomic data. Our findings suggest that SC impairments result from their inherent genetic abnormality rather than from environmental influences. The observed biological changes are intrinsic and not reactive to the pathological surrounding of DMD muscle. Full article