Ageing and mitochondrial disease progression

Dr Tiago Gomes is a neurology specialist from Portugal who recently started a PhD in the WCMR. Following his presentation in this week’s WCMR ‘Research in Progress’ meeting, he tells us more about his research project.

Mitochondria are crucial for cells to produce energy and function normally. When mitochondria malfunction, it is often the most energy demanding organs that are affected as part of mitochondrial disease. The muscle is very frequently involved, causing what clinicians call mitochondrial myopathy. Muscle function goes way beyond the ability to move. Eye movement, speech, facial expression, breathing, chewing and swallowing can all be severely affected by mitochondrial myopathy. Mitochondrial diseases are not uncommon and even isolated mitochondrial myopathy can frequently cause severe problems  with vision, communication, feeding and breathing, as well as mobility and dexterity. Additionally, mitochondrial myopathy is progressive and can lead to increased incapacity over time.

Mitochondrial diseases are complex genetic diseases with highly variable presentation, even between patients with the same spelling error in their DNA. Our ability to predict disease progression and prognosis is currently limited because we do not know how the disease progresses or importantly, how to stop this progression. However, we know that ageing causes an accumulation of mitochondrial dysfunction in the muscle of individuals without mitochondrial diseases. Mitochondrial dysfunction is also seen in several disorders associated with old age, such as brain diseases (i.e. Parkinson’s disease) and age-related decrease in muscle bulk and function called sarcopenia.

For this reason, I became interested in investigating how ageing affects mitochondria that are already dysfunctional due to a hereditary mitochondrial disease. In my PhD, I want to learn how mitochondrial genetic errors and normal ageing interact to create disease progression. This knowledge will help future studies to develop treatments directed against these progression mechanisms to prevent or delay mitochondrial disease progression in patients.

For this type of research, we require muscle tissue samples from patients and the study would not be possible without the generosity of our patients. I would like to thank all our patients whose contribution will be essential for our ability to continue to carry out research to help others affected by mitochondrial disease.