Our Interview with Dr Luciana Torquati
Dr Luciana Torquati is a Lecturer in Nutrition at the University of Exeter. She completed her PhD in Nutrition and Dietetics at the University of Queensland in Australia in 2016, and thereafter became an Honorary Research Fellow. She has recently completed a study that is investigating the effect of exercise on the gut microbiome in patients with Type 2 diabetes. We caught up with her to find out more about her career path and research…
1. Can you tell us about your career path, and how you became a Lecturer in Nutrition at the University of Exeter?
I started to develop an interest in nutrition during my last year at high school, where I learnt about nutrition science and worked as a sous chef. This interest kept growing and led me to undertake a PhD in Nutrition and Dietetics at The University of Queensland. Here I worked alongside experts in exercise and physical activity, which inspired me to learn more about this and look at health from a diet and exercise perspective.
I then moved to the UK, where I registered as a Nutritionist with the Association for Nutrition and secured my first position as a lecturer at Birmingham City University. Then the University of Exeter opened a position to develop a new BSc program in Nutrition – this represented a unique opportunity to channel my passion for nutrition and work alongside experts in nutrition physiology and exercise.
2. What led to your interest in physical activity and the metabolic syndrome, and in particular their relation to the gut microbiome?
During my first degree (BSc Biology in Nutrition), I became very interested and fascinated by bacteria and how they populate every corner of the world. My Master’s degree then included a few modules on functional foods and physiopathology, and that is when I learnt about the relationship between nutrition and health, microbiome, probiotics and prebiotics. My fascination in this field just grew exponentially. However, at that stage I was equally interested in public health nutrition, and decided to take that route in my PhD and post-doc at The University of Queensland. During this time, I worked alongside experts in physical activity and health which made me interested in in this field and how it fits with nutrition and health. As exercise research started to focus on the potential link to gut microbiome, myself and my colleagues got really excited at how this link might work in metabolic conditions. We had the opportunity to measure gut microbiome changes in people with Type 2 Diabetes who were part of an ongoing exercise study, and were also interested in what would happen to their ‘bugs’ after 8-weeks of exercise.
3. During your Research Fellowship, you were involved in investigating the impact of nutrition and physical activity on the gut microbiome in patients with Type 2 diabetes. Can you tell us a bit more about the research and why it’s important to consider the gut microbiome and physical activity in patients with Type 2 diabetes?
There is a surmounting amount of research showing the beneficial role of nutrition, physical activity and exercise in improving our cardiovascular system and insulin sensitivity, and reducing inflammation. These are key aspects that can help alleviate metabolic syndrome, if not resolve it in the majority of cases. This potential to me is fascinating and means we can improve people’s quality of life with an approach that is virtually free. In this mix, we have the gut microbiome, which so far research told us it was involved in breaking down dietary fibre and helped modulate immune response. Now more and more research is highlighting the importance of gut microbiome metabolites, these are short chain fatty acids (acetate, butyrate, and propionate). These have strong anti-inflammatory action with studies also showing a role in improving insulin sensitivity. As exercise could increase the production and number of short-chain fatty acids-producing bacteria, this could prove a novel mechanism to alleviate type 2 diabetes.
4. Can you share what your role was as the Research Fellow in this study?
In this study, I was involved in explaining the procedures to participants and explaining why looking at the gut microbiome is important. I was responsible for processing the samples to extract and measure short-chain fatty acids, and to analyse this and bioinformatics data. We presented our preliminary findings at the European Conference of Sport Science and soon we will be publishing the complete data in a peer-review paper.
5. In 2019, you published a paper in Nutrients showing that dietary fibre is independently associated with increased circulating interleukin-22 (IL-22) in individuals with metabolic syndrome. Can you share more about the study and what we can learn from it? Do you think more research warranted?
This is a study that aimed to demonstrate if the associations between diet and IL-22 observed in mice, stands in humans. The growing animal research in this fields shows IL-22 can restore gut barrier function and glycaemic control, by improving beta-cell function (cells in the pancreas that produce insulin). As fibre is digested into short-chain fatty acids, these can regulate immune cells like T-cells that produce IL-22 and similar cytokines with anti-inflammatory effects. However, this mechanism has not been shown in humans. So as a first step, we looked at whether there is an association between fibre intake and circulating IL-22 levels. Against a wide variety of confounders (lipid profile, glucose metabolism, body composition, aerobic capacity, diet), fibre intake remains an independent predictor of IL-22 levels. Meaning these two factors are associated even when considering all other clinical aspects. This reinforces the concept of a beneficial role of dietary fibre in people with metabolic disorders. As our research was limited by being observational data (so no causation can be confirmed), this warrants more research to understand the mechanism. Specifically we need to look if changing dietary fibre intake results in changes in specific gut bacteria and metabolites, and how these relate to changes in metabolic markers.
6. How can dietary fibre improve our inflammatory response, and does this relate to the gut microbiome? Do you perhaps think that other dietary components, particularly those that interact with the gut microbiome, could be investigated in relation to inflammatory markers such as IL-22?
Fibre (specifically the fraction that escapes digestion) is fermented by gut bacteria to produce short-chain fatty acids. These can regulate immune cells like macrophages and T-cells that produce cytokines with anti-inflammatory effects, and often responsible to alleviate gut barrier disruption (inflammation). It would be interesting to look at other dietary components that interact with gut microbiome and have shown an anti-inflammatory effect, such as polyphenols. In moving this research in fibre and other components, we should aim to measure a battery of cytokines both at local and systemic level.
7. What future research would you like to see in the field of physical activity, the metabolic syndrome and the gut microbiome?
I think moving forward I would like to see (and be part of) diet and exercise research in metabolic syndrome, as it is interesting to understand how these two factors work in synergy in the context of gut microbiome. My current PhD student at the University of Queensland is investigating this, by looking at the effect of inulin and exercise training on gut microbiome outcomes. I have recently been awarded a British Nutrition Foundation grant, to look at the role of acetate (main gut microbiome metabolite) on exercise endurance. This project will help develop the basis for larger projects to investigate the role of specific gut bacteria in this mechanism.
An important and challenging aspect of future research is to find new ways to translate intervention success factors into feasible changes that participants can keep in the long term. This is the only way we can have an impact in improving people’s health and quality of life.
8. You have conducted a lot of research throughout your career – are there any projects that you feel were the most instrumental within the development of your career?
I think my PhD project was the most influential in shaping my career, as it gave me the opportunity to learn how to work with people and how research studies work in the real world. Having to develop a diet and physical activity intervention for nurses, meant I had to do a lot of formative work before the actual research. This included reading and meeting potential participants to understand how to design an intervention that takes into account nurses’ work and time demands. During my PhD I also attended international conferences, assisted with teaching in undergraduate modules and worked as a part-time research assistant. All of those experiences provided different pieces that shape me and lead me to this career pathway.
9. What does a typical working day look like for you? And how have you had to adapt during the COVID-19 pandemic?
On a typical pre-covid day, I would have breakfast and then cycle to work (do as you preach!). I would be working in my office developing a lecture and finding funny memes to convey the key message of that lecture. Then lunch with some of my colleagues, and then back to work which often in the afternoon is data analysis and trying to put findings of a research study into context. The office work is alternated by meetings, a dissertation student popping by to discuss their project, a quick tea break where you might bump into a colleague which often results in exciting research conversations, a practical session I need to deliver in the lab, or meeting a participant for data collection. Not one day is the same!
So you can see how COVID-19 has change everything, as I have been working from home since March before the first lockdown hit. It has been fine but very different, as you miss out on all the interactions with students and colleagues, and research with participants. Luckily the revised guidelines have allowed universities to have some in-person practical sessions, which meant I managed to meet some students this term. I am now looking forward to re-starting my research.
10. If you could give students one piece of advice, what would it be?
Stick to what you are really interested and passionate about, even if it seems difficult or impossible to achieve. It might take time and things are rarely straightforward, but if you are working towards something you really want it all becomes easier. And very rewarding in the end.