Study of Clinical Features and Diagnosis Pattern of Duchene Muscular Dystrophy in Southern India

Background Duchene muscular dystrophy (DMD) is an X-linked progressive muscle disorder that is characterized by proximal muscle weakness followed by a premature death in young boys. There is a low index of reports on diagnosis ratio and clinical features in Southern India. Objective The present study aimed to conduct an observational survey on preliminary analysis, family history, associated complaints, and diagnosis ratio of DMD in southern regions of India. Materials and Methods A systematic observation and survey were conducted on clinically confirmed DMD patients registered between 2019 and 2021 through the questionnaire. The questionnaire and pattern of study were identified by exploring published and unpublished studies available from electronic databases and critical assessment criteria considered by physicians. Preliminary analysis such as onset criteria, motor difficulties, milestone delay; family history and consanguinity analysis; chief complaints (ambulatory status, lordosis, respiratory, and cardiac outcomes), associated complaints such as enlarged tongue, oral hygiene, behavioral problems; and other similar parameters were studied. An assessment of the diagnosis rate and pattern was performed. Statistical analysis The data were reviewed and interpreted through statistical methods mean ± standard deviation represented as a percentage. Results In total, 400 DMD patients were included and 250 participated in the study. The onset age group was 2 to 5 years in 37% of the population. Milestone delay was seen in 86%; consanguinity marriage of parents was reported in 39%. Frequent falls were reported in 62% in 5 to 8 years old group. Wheelchair status was reported in 65% in 9 to 12 years old. Cervical and lumbar lordoses were seen in 57 and 69%, respectively, in above 13 years old. Respiratory and cardiac complications were 88 and 78% reported in above 13 years old, respectively. Other major associated complaints such as enlarged tongue were reported in 79%. Fifty-one percent underwent genetic diagnosis and 79% of the population underwent serum creatine phosphokinase (CPK) analysis for the confirmation of DMD. Conclusion In this study population of South India, milestone delay was a major observation. Although there was a slight margin, family history shows “no blood relation among parents” in the majority of the study population. Chief complaints were predominantly severe above 13-year age group population. Serum CPK was the first choice for the first investigation, which is followed by a genetic diagnosis.

Non-gynaecological Applications of Menstrual-derived Stem Cells: A Systematic Review

Menstrual-derived Stem Cells (MenSC) are a potential novel source of mesenchymal stem cells. There is an increased interest in investigating the therapeutic potential of MenSC due to the various advantages they exhibit, when compared to other types of stem cells. MenSC are obtained non-invasively from menstrual blood. Thus, collection of MenSC is simple, reproducible and can be carried out periodically, with minimal complications. MenSC are present in abundance, are highly proliferative, exhibit a low immunogenicity and lack ethical issues. MenSC have shown the ability to differentiate into several lineages. The therapeutic potential of MenSC in non-gynaecological applications has been investigated in wound healing, neurological, musculo-skeletal, cardiovascular, respiratory, and liver disorders, as well as in diabetes and cancer. Human clinical trials are limited. To date, therapeutic efficacy and safety have been reported in patients with Avian influenza A subtype H7N9, COVID-19, congestive heart failure, multiple sclerosis and Duchene muscular dystrophy. However, further clinical trials in humans should be conducted, to study the long-term therapeutic effects of these stem cells in various diseases and to further explore their mechanism of action. This systematic review focuses on the application of MenSC in non-gynaecological diseases.

Neuromuscular disease - Gene transfer for children

Successful gene transfer therapy (GTT) provides a functional copy of a gene to appropriate tissues for affected patients. While technically difficult, GTT holds great promise for treating and even curing previously fatal diseases. GTT for Spinal Muscular Atrophy is available commercially and ongoing studies continue to show it is safe and effective. Subclinical liver dysfunction is more common in older, heavier children receiving higher vial loads. Human trials support preclinical studies showing early timing of therapy is important. GTT for Duchene Muscular Dystrophy has required strategic approaches to create mini- and micro-dystrophin genes that will fit into available viral vectors. There are multiple ongoing studies that overall demonstrate good safety and efficacy. GTT for X-Linked Myotubular Myopathy is being studied in an ongoing trial that has shown improvement in respiratory function (including ventilator independence), neuromuscular function, and histopathological evaluation. Three patients with severe cholestatic liver dysfunction have died. Evaluation is ongoing to better understand these events. While GTT for neuromuscular disorders holds significant promise, it is not without risks and requires in-depth knowledge of the disease, abundant pre-clinical work, careful patient education, and ongoing patient care. There are a number of key questions that must be considered regarding the feasibility of expanding GTT to new disorders These examples illustrate how advances in GTT benefit children on a population level and may themselves benefit from early detection by NBS. By becoming involved in advocacy at state and federal levels, families and physicians can impact newborn screening policy and implementation regarding these disorders.

Mislocalisation of Pax7 and Its Interaction with Importin-α1 (KPNA2) in Dystrophin-Deficient Myoblasts

Background: Pax 7 is one of the key factors in the development of tissues and organs during embryogenesis. It has been suggested that Pax7 may play a major role during myogenesis. Our previous study has shown that Pax7 cell is attenuated in the mdx embryo during gestation as well as in dystrophic muscle indicating that an absence of dystrophin in muscle affects pax7 regulation in Duchene Muscular Dystrophy (DMD). Therefore, we aimed to investigate the Pax7 expression pattern as well as their specific transport protein in dystrophin-deficient myoblasts at postnatal/juvenile stage. Methods: In this study, dfd13 (dystrophin-deficient) and C2C12 (non-dystrophic) myoblasts were cultured under normal conditions prior to further analyse its expression pattern at proliferating stage via western blot and immunofluorescence analysis. Protein prediction and protein interaction study was done via in silico and co-immunoprecipitation analyses, respectively.Results: It was found that Pax7 localised in the cytoplasm of dystrophin-deficient myoblasts and high expression retained during differentiation. Co-localisation analysis of Pax7 with subcellular markers indicated that Pax7 is highly synthesised at their proliferative state. Interestingly, it is shown that Pax7 possess a nuclear location signal and KPNA2 was suggested as an escort protein for Pax7 translocation into the nucleus. Conclusion: For the first time, our study showed that Pax7 is mislocalised in dystrophin-deficient myoblasts and it is postulated that KPNA2 is the karyopherin-α which might be responsible for Pax7 translocation into the nucleus.

Early Identification of DMD in the Setting of West Syndrome

Duchene muscular dystrophy (DMD) is the most common muscular dystrophy in childhood, affecting ∼1:5000 male live births worldwide. DMD is a genetic disorder with X-linked recessive inheritance pattern characterized by a severe muscular phenotype with progressive muscle weakness and atrophy due to pathogenic variations within the DMD gene. Two cases are reported to date in the literature of individuals with a diagnosis of both DMD and West syndrome; neither of which had the degree of additional genetic abnormalities that our patient demonstrates. We present a male infant with West syndrome, and multiple pathogenic variants, the ominous one being in the DMD gene. This case adds to confirming that West syndrome expands the spectrum of epilepsy that may be present in DMD patients. Additionally, this case can identify how the early use of steroids may shed light on effects of early symptomatic treatment of DMD.

HK022 bacteriophage Integrase mediated RMCE as a potential tool for human gene therapy

HK022 coliphage site-specific recombinase Integrase (Int) can catalyze integrative site-specific recombination and recombinase-mediated cassette exchange (RMCE) reactions in mammalian cell cultures. Owing to the promiscuity of the 7 bp overlap sequence in its att sites, active ‘attB’ sites flanking human deleterious mutations were previously identified that may serve as substrates for RMCE reactions for future potential gene therapy. However, the wild type Int proved inefficient in catalyzing such RMCE reactions. To address this low efficiency, variants of Int were constructed and examined by integrative site-specific recombination and RMCE assays in human cells using native ‘attB’ sites. As a proof of concept, various Int derivatives have demonstrated successful RMCE reactions using a pair of native ‘attB’ sites that were inserted as a substrate into the human genome. Moreover, successful RMCE reactions were demonstrated in native locations of the human CTNS and DMD genes whose mutations are responsible for Cystinosis and Duchene Muscular Dystrophy diseases, respectively. This work provides a steppingstone for potential downstream therapeutic applications.