AN EXERCISE-BASED CONCEPT FOR DRUG TARGET DISCOVERY

Cardiovascular and muscular diseases are serious public health problems worldwide and are among the most common causes of death. Therefore, research to develop more effective therapies is necessary. Although most medications against cardiac and muscular diseases are weakly effective, it is well known that the effects of physical activity in cardiac and muscular health are potent. Exercise improves heart function, delay ageing and enhances muscle capacity in both healthy and diseased populations. Although the effects of exercise are clear and well known, two facts hinder the use of exercise as a universal therapy: many patients are simply unable to exercise sufficiently to gain significant benefits (e.g. patients recovering from accidents, with neuromuscular disorders, etc.), and part of the population experiences poor responsiveness to exercise training. In this sense, this project aimed to understand how physical activity orchestrate its effect at the molecular level, inside our cells, so that we could activate those mechanisms artificially and hopefully deliver part of the benefits of exercise using experimental therapies. During the project, we discovered various genes and proteins that were activated by exercise in the heart and skeletal muscles, in both lab animals and humans. We manipulated some of those molecules in cells and living animals, showing potentially therapeutic effects. Our discoveries were published in important scientific journals and are explained below: - Using modern technologies for gene sequencing, we discovered several genes and protein (which we call “mechanisms of exercise”) that were dysregulated by heart diseases in cardiac cells and were rescued by physical activity in lab animals. We manipulated several of those mechanisms in human cardiac cells cultivated in the lab, to understand how they worked, and found one that was essential for the heart to use energy efficiently. This protein is called PRODH. In summary, the amount of PRODH is reduced in sick hearts and increased in hearts of exercised animals. By using gene therapy methods, we found that by increasing the amount of PRODH improved metabolic function and protected cardiac cells against damage. Those findings indicate that PRODH is a promising target for gene therapies against heart disease. - In a collaboration with international scientists, we also discovered new mechanisms that are associated with high exercise capacity, which is a strong predictor of good long-term health and longevity. We contributed with two discoveries: (1) a list of genetic biomarkers that distinguish people with low vs. high exercise capacity; and (2) specific protein modifications that occur in the heart and muscle of rats that are born with very exercise capacity. These findings are important because they contribute to the development of new biomarkers, potentially able to predict how cardiac and muscle health of a person may change in the future, thereby allowing early measures to delay symptoms. - We also contributed to a study that identified a protein that appears to be important for the control of muscle mass in cancer. Cancer patients lose lots of muscle mass and function, so this protein (called COPS2) sheds light onto potential new therapies to improve muscle capacity in cancer patients. - Finally, by combining a large computational analysis with biochemical experiments, we discovered that a new molecule called CYTOR regulates many processes inside muscle cells. We found that CYTOR is also very important for muscles to work properly, and that CYTOR is partially lost upon ageing. Most importantly, we used gene therapy methods to boost CYTOR in aged muscles, and that was sufficient to improve muscular function in old lab animals. This work resulted in a patent application and will hopefully contribute for the development of new drugs to treat muscular diseases.

Our findings, published in respectable international journals, are important contributions for and advance the fields of exercise science, cardiovascular medicine, and muscle biology. The results regarding the molecular mechanisms of exercise, and particularly the therapeutic manipulations thereof, will hopefully serve as inspiration for future studies seeking new and more effective treatments against cardiac and muscular diseases. The provocative concept of activating “exercise molecules” offers a creative approach and expertise for therapeutic target discovery, and our results show that this process is feasible and have great potential in preclinical models. Ultimately, we aimed to contribute for future improvements in treatment for cardiac and muscular diseases in humans, and it is reasonable to conclude that our discoveries through this project offer significant insights in this direction. Importantly, the results of our CYTOR article were used as basis for a patent application entitled "Products and methods for promoting myogenesis", filed at the UK patent office (assessment is ongoing). This is further evidence that our findings also have industrial relevance.

The health benefits of physical activity are among the most extraordinary phenomena in biology. Although regular physical activity promotes undisputed benefits to heart and muscle, and is a major component of chronic disease management, two facts hinder the use of exercise as a universal therapy: many patients are simply unable to exercise sufficiently to gain significant benefits (patients recovering from accidents, with neuromuscular disorders etc), and part of the population experiences poor responsiveness to exercise training. Therefore, therapies able to trigger or anticipate specific aspects related to the benefits of exercise in disease contexts would have a major positive impact in patient outcome. I hypothesize that molecular mechanisms activated by exercise in the heart and skeletal muscles will shed new light on promising therapeutic targets and guide the development of novel pharmacological therapies against cardiovascular (CVD) and muscular diseases. I will test the provocative concept that artificial activation (gene therapy) of these mechanisms can yield therapies to treat CVDs or muscle disorders. Towards this goal, I recently took advantage of unbiased technologies to discover novel candidate exercise-induced targets, and here I present promising evidence by manipulating these molecules in vitro. Built upon this knowledge, here I propose a translational project to understand these mechanisms in details and expand the concept towards therapeutics, by targeting these molecules in preclinical models in vivo. My studies will propel a pioneering research line oriented towards issues of utmost medical importance; CVDs and muscular disorders. Upon completion, the project will yield three broad impacts: 1. Capture the biomolecules activated by exercise in cardiac and skeletal muscles; 2. Characterize these mechanisms and test their therapeutic potential in disease models; 3. Lay the foundation for novel therapies against CVD and muscular disorders;