Therapeutic impact of plant compounds on muscle structure and function
Duchenne Follistatin Gene Therapy Trial
Developing small molecules to target Duchenne
Men with Duchenne on end-of-life care decision making
Professor David Abbott, Bristol University
Over the next 12 months, Professor David Abbott will interview 20 men with the life-limiting condition, Duchenne muscular dystrophy, on their views on how family members, friends and health and social care professionals can best approach supporting people to make decisions about end-of-life care.
Qualitative researcher Professor Abbott will work with psychologist Dr Helen Prescott to collect the views of the men, all of whom will be over 20 years old, and produce recommendations on issues including opening discussions on death and dying and understanding the perspectives of children and young adults with life-limiting conditions.
Professor Abbott said: "We hope this study will give men with Duchenne muscular dystrophy the opportunity to tell us if and how they would like to embark on conversations about end-of-life issues. This remains a sensitive and often taboo topic for society in general, yet our previous research suggests that many men with Duchenne would welcome the opportunity to air their questions and fears. We hope that by understanding the views of the research participants, clinicians and other relevant professionals will be helped to initiate or respond to these conversations."
Altering the muscle environment for stem cells
Professor Jennifer Morgan, University College, London,
We are investigating ways to maximise the efficiency of stem cell transplantation in a mouse model of Duchenne muscular dystrophy. More specifically, we are studying how irradiation of the dystrophic mouse muscle before transplantation enhances the amount of muscle formed by the transplanted stem cells.
This year we have demonstrated that radiation improves stem cell transplants in dystrophic muscle but not in non-dystrophic muscle. We have shown that stem cells work best when transplanted into dystrophic muscles in which dying cells are present. We have transplanted different types of muscle cells extracted from irradiated muscles, mixed with stem cells from normal muscles, into non-irradiated dystrophic muscles, to see which one of these irradiated cell types helps the stem cells engraft into the muscle. The final results from these co-transplant experiments are currently being analysed.
We have also prepared samples to undergo next-generation sequencing, a high throughput technique that will allow us to see any changes in gene activity throughout the whole genome, across the whole muscle, under different conditions. This will tell us what genetic pathways are changing significantly in response to radiation and guide further research.
Our future work for the coming year will be:
To determine whether successful stem cell transplantation correlates with the number of dying cells present within the transplanted muscle.
To complete the analysis of our co-transplant experiments, to determine which cells extracted from irradiated muscle can improve the function of muscle stem cells.
To perform next generation sequencing, to allow us to see changes in gene expression in irradiated compared to non-irradiated muscles. This means we can find genes or groups of genes that could be important targets for therapeutic intervention that might promote more efficient stem cell transplantation.
Developing small molecules to increase Utrophin
Dr Angela Russell, University of Oxford
Dr Angela Russell from the University of Oxford has continued to develop new compounds with an improved ability to increase levels of utrophin protein in cells. These new compounds are structurally-related to the utrophin-modulating hits identified from our recent drug screen and have been optimised to improve their drug-like properties, such as solubility. The biological activity of the compounds is assessed in cell-based experiments designed to measure how much they activate utrophin gene expression. Throughout this project so far, over 150 different compounds have now been synthesised and tested, 25 of which were prepared by the student over the past 11 months.
They have also conducted structure activity relationship studies around the most promising hit compound, OX01914. These studies explored the key structural features that are essential or non-essential for modulating utrophin levels in cells from the mdx mouse model and from people with Duchenne muscular dystrophy. Additionally we have prepared 'probe' molecules, based on OX1914, which we will use to identify the specific proteins the molecule interacts with, therefore telling us the identity of the molecular target of the compounds. This will help us understand the mechanism through which it acts to increase utrophin levels, and will also allow us to make more potent molecules using computer based design methods.
Finally, they have continued to progress the UtroDMD Alliance (the partnership between Muscular Dystrophy UK, Muscular Dystrophy Association, Medical Research Council, University of Oxford and Summit Therapeutics) which represents a joint enterprise to bring focus, discipline and unparalleled domain expertise to the discovery and development of novel utrophin modulator therapies for the potential benefit of people with Duchenne muscular dystrophy.
Preparation of the anti-fibrotic Halofuginone
Fibrosis is debilitating for Duchenne muscular dystrophy patients, yet there are no anti-fibrotic agents available as a treatment option. Halofuginone is a promising anti-fibrotic with extensive basic and clinical research in support of use in DMD. We have assembled a strong team to drive this exciting candidate through production and into a Phase II clinical trial.
Discovering Biomarkers for Duchenne muscular dystrophy
Professor Mathew Wood, University of Oxford
MicroRNAs are small DNA-like molecules that play a major role in the control of cell functions. They are released from cells and can be found in various body fluids including the blood, and can report valuable information on the state of the cells from which they originated.
Some microRNAs in the blood could therefore reveal information about the progression of a condition and could potentially be used as biomarkers (small molecules that can be easily measured and whose levels change in line with the severity and progression of a condition).This project aims to identify microRNAs which could be used as biomarkers for Duchenne muscular dystrophy.
During the first year, the student has familiarised herself with the literature and laboratory skills that will be required for the project, such as taking samples and collecting RNA and protein. She has also started analysing microRNAs in blood taken from two different mouse models, each with a different genetic mutation, to understand the effect of these mutations on the condition. This work is on-going.
The next step is to look at different ages in one of these mouse models to see how microRNAs in the heart and blood change over time; this will give a better understanding of how the condition progresses in the mouse model. The mice will also be treated with a molecular patch (known as an exon skipping approach) to assess what changes occur in the blood and heart, and how much we can restore heart function at a cellular level.
Repurposed Cancer Therapeutics
Professor Steve Winder
Harrison's Fund, alongside other charities, is involved in this research project led by Professor Steve Winder, on Repurposed Cancer Therapeutics as Treatments for DMD. The below report covers the 6 month period from February to August 2017.
Annual Report covering the 6 month period February 2017 to August 2017 - Repurposed Cancer Therapeutics as Treatments for DMD
The original aims of the project were:
1. Assess the long-term efficacy of the tyrosine kinase inhibitors Dasatinib, Saracatinib and Bosutinib in reducing the dystrophic patho-physiology in mdx mice.
2. Assess the long-term efficacy of the proteasome inhibitor Carfilzomib in reducing the dystrophic patho-physiology in mdx mice.
3. Assess the possible synergistic effect of tyrosine inhibitors combined with proteasome inhibitors in further reducing the dystrophic patho-physiology in mdx mice..
During the last 6 months, the RA supported by this grant has had several health-related absences, meaning that we have lost 3 months working time on the project. Nonetheless, with support from other staff members in my lab and myself, all in vivo animal studies in relation to the original aims have now been completed.
Some analysis from aim 1 remains to be finished off, but this will be combined with the same type of analysis also being conducted on the samples from aims 2 and 3, making for some efficiency savings. The RA is currently on a 50% phased return, and due to return to full-time working on 11th September. It should be able to complete all remaining analysis in the last 2 months of the project.
The proteasome inhibitor carfilzomib (Carf: 2.5 mg/kg), Src tyrosine kinase inhibitor bosutinib (Bos1: 25 mg/kg) and a combination of carfilzomib plus bosutinib (Carf+Bos: 2.5 + 25 mg/kg respectively) showed no improvement in physical performance over 12 weeks, in fact compared to control (Cont) there was a significant deterioration. This is in marked contrast to the significant improvement seen with bosutinib at the higher dose of 50mg/kg (Bos2). Analysis of the other parameters (in progress), such as serum biomarkers, central nucleation, inflammation and fibrosis will be informative in revealing possible reasons for the drop in performance. The data do highlight the need for more in depth dose-response studies than have so far been possible. Particularly with respect to bosutinib which over a two-fold concentration range, went from a 50% reduction to a 150% increase in physical performance.
The carfilzomib data were disappointing, especially given the promising results of experiments carried out in zebrafish. Nonetheless, the reduced physical activity from either drug alone was not worsened when in combination, suggesting that at the right dose combination there still could be benefit to administration of both drugs together.
However we should await the more in depth histopathological analysis before drawing frim conclusions.
Steve Winder, Sheffield