Dataset Information

Uniform sarcolemmal dystrophin expression is required to prevent extracellular microRNA release and improve dystrophic pathology.

ABSTRACT:

Background

Duchenne muscular dystrophy (DMD) is a fatal muscle-wasting disorder caused by genetic loss of dystrophin protein. Extracellular microRNAs (ex-miRNAs) are putative, minimally invasive biomarkers of DMD. Specific ex-miRNAs (e.g. miR-1, miR-133a, miR-206, and miR-483) are highly up-regulated in the serum of DMD patients and dystrophic animal models and are restored to wild-type levels following exon skipping-mediated dystrophin rescue in mdx mice. As such, ex-miRNAs are promising pharmacodynamic biomarkers of exon skipping efficacy. Here, we aimed to determine the degree to which ex-miRNA levels reflect the underlying level of dystrophin protein expression in dystrophic muscle.

Methods

Candidate ex-miRNA biomarker levels were investigated in mdx mice in which dystrophin was restored with peptide-PMO (PPMO) exon skipping conjugates and in mdx-Xist^?hs mice that express variable amounts of dystrophin from birth as a consequence of skewed X-chromosome inactivation. miRNA profiling was performed in mdx-Xist^?hs mice using the FirePlex methodology and key results validated by small RNA TaqMan RT-qPCR. The muscles from each animal model were further characterized by dystrophin western blot and immunofluorescence staining.

Results

The restoration of ex-myomiR abundance observed following PPMO treatment was not recapitulated in the high dystrophin-expressing mdx-Xist^?hs group, despite these animals expressing similar amounts of total dystrophin protein (~37% of wild-type levels). Instead, ex-miRNAs were present at high levels in mdx-Xist^?hs mice regardless of dystrophin expression. PPMO-treated muscles exhibited a uniform pattern of dystrophin localization and were devoid of regenerating fibres, whereas mdx-Xist^?hs muscles showed non-homogeneous dystrophin staining and sporadic regenerating foci.

Conclusions

Uniform dystrophin expression is required to prevent ex-miRNA release, stabilize myofiber turnover, and attenuate pathology in dystrophic muscle.

SUBMITTER: van Westering TLE

PROVIDER: S-EPMC7113513 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Uniform sarcolemmal dystrophin expression is required to prevent extracellular microRNA release and improve dystrophic pathology.

van Westering Tirsa L E TLE Lomonosova Yulia Y Coenen-Stass Anna M L AML Betts Corinne A CA Bhomra Amarjit A Hulsker Margriet M Clark Lucy E LE McClorey Graham G Aartsma-Rus Annemieke A van Putten Maaike M Wood Matthew J A MJA Roberts Thomas C TC

Journal of cachexia, sarcopenia and muscle 20191217 2

<h4>Background</h4>Duchenne muscular dystrophy (DMD) is a fatal muscle-wasting disorder caused by genetic loss of dystrophin protein. Extracellular microRNAs (ex-miRNAs) are putative, minimally invasive biomarkers of DMD. Specific ex-miRNAs (e.g. miR-1, miR-133a, miR-206, and miR-483) are highly up-regulated in the serum of DMD patients and dystrophic animal models and are restored to wild-type levels following exon skipping-mediated dystrophin rescue in mdx mice. As such, ex-miRNAs are promisin ...[more]

PMID: 31849191

Similar Datasets

Project description:Although the initial concepts of stem cell therapy aimed at replacing lost tissue, more recent evidence has suggested that stem and progenitor cells alike promote postischemic neurological recovery by secreted factors that restore the injured brain's capacity to reshape. Specifically, extracellular vesicles (EVs) derived from stem cells such as exosomes have recently been suggested to mediate restorative stem cell effects. In order to define whether EVs indeed improve postischemic neurological impairment and brain remodeling, we systematically compared the effects of mesenchymal stem cell (MSC)-derived EVs (MSC-EVs) with MSCs that were i.v. delivered to mice on days 1, 3, and 5 (MSC-EVs) or on day 1 (MSCs) after focal cerebral ischemia in C57BL6 mice. For as long as 28 days after stroke, motor coordination deficits, histological brain injury, immune responses in the peripheral blood and brain, and cerebral angiogenesis and neurogenesis were analyzed. Improved neurological impairment and long-term neuroprotection associated with enhanced angioneurogenesis were noticed in stroke mice receiving EVs from two different bone marrow-derived MSC lineages. MSC-EV administration closely resembled responses to MSCs and persisted throughout the observation period. Although cerebral immune cell infiltration was not affected by MSC-EVs, postischemic immunosuppression (i.e., B-cell, natural killer cell, and T-cell lymphopenia) was attenuated in the peripheral blood at 6 days after ischemia, providing an appropriate external milieu for successful brain remodeling. Because MSC-EVs have recently been shown to be apparently safe in humans, the present study provides clinically relevant evidence warranting rapid proof-of-concept studies in stroke patients.Transplantation of mesenchymal stem cells (MSCs) offers an interesting adjuvant approach next to thrombolysis for treatment of ischemic stroke. However, MSCs are not integrated into residing neural networks but act indirectly, inducing neuroprotection and promoting neuroregeneration. Although the mechanisms by which MSCs act are still elusive, recent evidence has suggested that extracellular vesicles (EVs) might be responsible for MSC-induced effects under physiological and pathological conditions. The present study has demonstrated that EVs are not inferior to MSCs in a rodent stroke model. EVs induce long-term neuroprotection, promote neuroregeneration and neurological recovery, and modulate peripheral post-stroke immune responses. Also, because EVs are well-tolerated in humans, as previously reported, the administration of EVs under clinical settings might set the path for a novel and innovative therapeutic stroke concept without the putative side effects attached to stem cell transplantation.

Dataset Information

Uniform sarcolemmal dystrophin expression is required to prevent extracellular microRNA release and improve dystrophic pathology.

Background

Methods

Results

Conclusions

Publications

Uniform sarcolemmal dystrophin expression is required to prevent extracellular microRNA release and improve dystrophic pathology.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets