Meet Dr Riaz Akhtar

Dr Riaz Akhtar researches the biomechanics and biochemistry of biological tissues — particularly the aorta — to better understand ageing, disease, and improve clinical outcomes through interdisciplinary collaboration and advanced materials science techniques.

• Name – Dr Riaz Akhtar
• Position – Reader in Biomedical Engineering
• Group Name – LABB Group (Liverpool Aortic Biomechanics and Biochemistry Research Group)
• Joined University of Liverpool – 2011
• Born – Sutton Coldfield, UK
• PhD – The University of Manchester

What is your research about?

Biological tissues such as bone, blood vessels and skin are amazing materials. They are mostly made up of the same main constituents but have very different properties and functions. Due to hierarchical and intricate structures, synthetic biomaterials still lack the properties of the materials that they are replacing. I am interested in these natural biomaterials, especially within the context of ageing and disease. Better understanding and characterisation of these tissues will lead to improved therapeutics and treatment.

My PhD focussed on bone mechanics (hard tissue). Whilst I am still involved in bone research, I have mainly focussed on soft tissues such as blood vessels in recent years. Most of my research currently is on the aorta, the largest artery in the human body. Although I have been working on the aorta for over a decade, the importance of my research has become even more emphasised since last year when the aorta was classified as an organ by the medical community. We now understand that the aorta is not just a conduit for blood flow but plays a vital role in our cardiovascular system.

What I like about my research is that I can apply the tools, techniques, and expertise that I have developed to a range of problems outside of my core research. As an example, I have one project on bird flight feathers! The similarity between a flight feather and a human bone is a discussion for another time, perhaps over coffee.

What or who first inspired you to be interested in your research subject?

I first came across the technique of nanoindentation during my final year undergraduate project at The University of Manchester. A young lecturer called Dr Adrian Mann was offering a dissertation project on nanoindentation of bone. I had spent my undergraduate years in a materials science department understanding the importance of microstructure for material performance. Now, for the first time I was thinking about the performance of bone in relation to its microstructure. I found this fascinating, especially with the use of this novel technique. At the time, my mother was struggling with mobility due to musculoskeletal weakness and this became a motivator for me to understand the behaviour of bone with age and disease. Adrian moved to Rutgers University in the US but I was able to pursue my interest in bone micromechanics by commencing a PhD with another supervisor, Professor Paul Mummery, who also had an interest in natural materials. The transition to soft tissues and in particular the aorta came later when I started a postdoctoral position in Professor Brian Derby’s lab at Manchester. Brian was a great mentor and encouraged me to look for external funding and opportunities. I obtained a British Heart Foundation award which enabled me to gain new skills in cardiovascular sciences and I began working in both engineering and cardiovascular sciences, a truly interdisciplinary appointment. I spent the next three years working with Professor Derby in Engineering, Professor Kennedy Cruickshank, a clinician, who had an interest in the aorta and Professor Michael Sherratt, a biochemist. This was a great experience of science without traditional boundaries, and I have carried this multi-disciplinary approach with me ever since.

What are you most proud of achieving during your research career so far?

This is a difficult question to answer but it would probably be the network that we have built up inside and outside the University of Liverpool. When I first reached out to Liverpool Heart and Chest Hospital many years ago, I could not have imagined that we would be in the position we are now with not just a successful research group but having established an aortic tissue biobank collection, a biennial conference and successful collaborations across the UK and around the world. In the past two years alone, our research group has co-hosted a workshop on aortic diseases in Shanghai and visiting two leading centres in the US (Baltimore and Yale). In addition, we have a strong partnership with a charity, The Aortic Dissection Charitable Trust (ADCT). We have also organised workshops for the public and outreach activities. Working with a patient advocacy charity such as ADCT is key to translation of our research. Although our work is fundamental science, I am proud that we have so much buy-in from the people directly affected by the disease through themselves or a loved one. The international clinical and scientific collaborations are also enabling us to make progress much quicker than would be possible alone.

What techniques and equipment do you use to conduct your research?

I spend a lot of time working with nanoindentation and atomic force microscopy (AFM). Both techniques are the key facilities in my Nanomechanics Lab. We are interested in the behaviour of biological materials at the micron and sub-micron level. Nanoindentation is a technique that enables us to do this but is also important for characterising the material properties of engineering materials. AFM is a well-known technique in materials science which enables us to generate images of materials at the nanoscale using a sharp tip which has a radius of a new nanometres mounted on a cantilever. The images are built up not using optics (as ‘microscopy’ suggests) but purely by the tip ‘feeling’ the surface and developing an image based on the topography or height of the features in the material. AFM can be a time-consuming technique but really rewarding when great images are obtained. I love getting cool images of collagen fibrils in the biological materials we work with.  

Both of techniques have been used by materials scientists for some years but the application to biomaterials and biomedical engineering has grown significantly and become more sophisticated in recent years.

I also work with various other imaging techniques, mechanical testing techniques and more recently with statistical modelling and machine learning.

Which other subjects are important for your research?

My research area is fundamentally interdisciplinary and would not be possible without working closely with other disciplines. Our “Liverpool Aortic Biomechanics and Biochemistry Research Group” embodies that in its name. Our group is different from many research groups at the University because we set out not to be the group of a certain PI but a collaborative endeavour. Three of us co-founded the group realising that our collective yet differing expertise was key to taking our research questions forward. Dr Jill Madine in Biochemistry and Prof. Mark Field (Liverpool Heart and Chest Hospital) and myself (Engineering) form our trio. Hence, I would say that Biochemistry is a subject key to my research as well as Clinical Medicine/Surgery.

One of the great things about biomaterials science as a discipline is that it is inherently broad and involves researchers with biology, chemistry, physics and engineering expertise. As such, it feels natural to be working with health and life scientists for my day-to-day research.

Over the years, I have had the pleasure of working with brilliant people from numerous disciplines. Some other examples that I can quote where I have had longstanding collaborations with colleagues outside of my discipline have been with physics, chemistry and data science/machine learning.

What is the key to running a successful research group?

It is the talented researchers that lead to success in a research group. I have been privileged to have some great students and researchers within my group over the years. I have supervised students with a range of scientific backgrounds including those who already have careers in their chosen disciplines and have embarked on PhD research part-time. The diversity of my research group has been a source of strength. My students come not only from numerous disciplines, but also with differing experiences and expertise. This is a positive thing, and we learn together and from each other. We try and have an inclusive and relaxed atmosphere within the group and when things get tough, there is a support network. I am always looking for opportunities for those in my research group to help further their skill development and expertise and this is appreciated by the members. 

What impact is your research having outside of academia?

We have focussed a lot on bicuspid aortic valve disease or BAV, over recent years. BAV is the most common congenital heart defect worldwide and is associated with aortic disease. Our research has shown that patients with BAV have aortas that may seem ‘at risk’ to a surgeon but the structural and biomechanical properties of their aorta suggest that they are not. This is likely to save patients from having unnecessary and complicated surgery. Some surgical commentaries have been written on our work and last year we ran a workshop bringing together patients, surgeons and academics to discuss the complexity of BAV from numerous angles. It was inspiring and humbling to hear from a patient at the workshop who had not just navigated this condition in difficult circumstances as a young man but also competed in martial arts at the highest level. We hope with time our research will lead to bespoke patient-specific treatment not just for BAV patients but for those with other aortic diseases. 

How do you plan to develop your research in the future?

Research is always fast-evolving. I am interested in applying the latest tools and techniques to our research questions. I am working more with machine learning approaches and trying to develop new experimental techniques. One of the areas I am looking to develop soon is the application of in vivo techniques, which can be used for modelling or predicting disease in the absence of any invasive surgery. We have some exciting projects currently generating pilot data. Watch this space.

What problem would you like to solve in the next 10 years through your research?

It would be amazing if we could make significant progress with aortic dissection. Aortic dissection is a dangerous, life-threatening condition where a tear occurs inside the wall of the aorta and can lead to rupture of the aorta. Often it is misdiagnosed, and we do not have a good biomarker for this condition. I would like to make a significant contribution to better diagnosis and treatment of aortic dissection. This would be impactful and prevent unnecessary deaths. Given the global partnerships I mentioned earlier, I am sure we can make progress over the coming years.

What advice would you give to someone considering a career in research?

Get some experience in a research lab if you haven’t already. Once you have a taste of research and have identified a topic or area, talk to lots of researchers in your field of interest. Find out what they are doing and what their day-to-day experience is like. If this is something that appeals to you, then go for it. You will find research highly rewarding. In addition, ensure you identify someone that can support you as a mentor as there is a lot to navigate especially when you are starting out in research. Finally, do not limit yourself to traditional discipline boundaries. Think outside of conventional subject norms.

Where can readers learn more about your research?

The stating point would be a couple of review articles that I wrote some time ago:

Characterizing the elastic properties of tissues

In vitro characterisation of arterial stiffening: From the macro- to the nano-scale

I co-authored the book ‘Mechanical Properties of Aging Soft Tissues’ which also serves as an introduction to my research interests.

If you are interested in an original article on a specific research project I have mentioned, please get in touch and I will happily share a relevant article.