Improving the treatment of eye diseases using regenerative medicine

ISTM recently ran a blog writing competition that was open to PhD students and young researchers with a view to improving their lay-writing skills and helping ISTM to play a greater role in the public dissemination of its research. After concluding the competition we will be publishing each entry in turn over the coming months. The 3rd prize winner of our competition was Rachel Gater, a PhD student in the Centre for Doctoral Training, ISTM.

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(Source: Microsoft word - Clip Art)

The retina is a complex layer of tissue at the back of the eye. It turns the visual information entering the eye into electrical signals, which are then sent to the brain for processing. Eye diseases such as glaucoma and macular degeneration can damage the retina, leading to significant sight problems and even blindness if left untreated. Glaucoma causes damage to the retina by a build up of pressure inside the eye, whilst macular degeneration involves deterioration of the centre of the retina; the most sensitive region. Although there are some existing treatments for eye diseases such as intravitreal injections and surgery, the success rate of these treatments is not very high and they can cause unpleasant side effects. Therefore, scientists in the field of regenerative medicine are working to develop better treatments for eye diseases.

There are generally two methods that scientists in the field of regenerative medicine can try when researching new treatments for eye diseases. The first approach is the possibility of triggering self repair processes (endogenous regeneration) to help the damaged eye tissues repair themselves. Certain amphibians, such as the newt, are already naturally able to replace their entire eye through endogenous regeneration! We still don’t fully know how amphibians do this, but it is believed that they store stem cells in certain areas of the eye. Stem cells are special because they have not yet transformed into a specific cell type and can therefore be triggered to turn into any type of cell. Therefore if the amphibian’s eye gets injured, the stored stem cells can replace any damaged cells and repair the eye. If scientists can work out the biology of exactly how amphibians do this, then they may be able to help trigger the same process for humans in the future!

(Source: Microsoft word - Clip Art)

Figure 1: Amphibians such as the newt are already naturally able to replace their entire eye through self repair processes (endogenous regeneration).

The second approach scientists in the field of regenerative medicine can try is the possibility of repairing damaged eye tissues using stem cell therapies. Stem cell therapies can be generated from sources such as embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs) and mesenchymal stem cells (MSCs). As shown in Figure 2, the retina of the eye is made up of many layers each containing different types of cells. These cells include rods (which help us with vision in darkness at night time) and cones (which help us with colour vision in the day time). There are also bipolar cells which do a bit more processing in the nuclear + plexiform layers, as well as ganglion cells which are important in helping to pass on information to the brain. As we know that stem cells can be triggered to turn into any type of cell, scientists believe that we might be able to turn stem cells into new retina cells such as rods, cones and ganglion cells. If successful, these cells could then be used to repair the retina if the eye gets damaged by disease or injury.

(Source: original)

Figure 2: The retina is made up of many layers each containing different types of cell.

So far scientists have been able to turn stem cells into rods, cones and ganglion cells inside a cell culture plate, but there is more work to do before the method can become a treatment given to patients. Even though we can grow the cells, one of the first challenges is figuring out how we can safely deliver the treatment into the patient’s eye. As the eye is so small and fragile, injection needles or surgery may cause further damage to the eye. Therefore, it is important to figure out the best way to precisely deliver the cells to the eye without it causing further damage or being painful for the patient. A second challenge is getting the cells to integrate and function correctly once they are inside the eye. Even if we can deliver the cells correctly, we would need to make sure that the cells are alive, in the correct place and performing their correct function once inside. For example, if we manage to deliver new cone cells into the eye and they correctly perform their role in colour vision, then we would know that the treatment has worked! Finally, a third challenge scientists will need to overcome is the possibility of immune-rejection. As stem cell therapies don’t always use the patient’s own cells, there is a chance that transplanted cells may be rejected, in the same way that a heart transplant might be rejected after heart transplantation surgery. To overcome this challenge, drug treatments such as immuno-suppression therapy may be used to help reduce the risk of rejection. Alternatively scientists might be able to use a patient’s own stem cells which would not be rejected by the body.

In summary, due to the low success rate of current treatments, scientists in the field of regenerative medicine are working to develop better treatments for eye diseases. The two main methods for this include the possibility of triggering self repair (endogenous regeneration) like amphibians can do naturally, or the use stem cell therapies to repair damaged eye tissues. Although scientists can turn stem cells into retina cells relatively successfully in a cell culture plate, challenges still need to be overcome. These challenges include figuring out how to safely deliver cell therapies into the eye, getting transplanted cells to function correctly once inside the eye and overcoming the risk of immune-rejection. If scientists can successfully overcome these challenges, these approaches are likely to transform the way that we treat eye diseases in the future!

Written by Rachel Gater, PhD Student, Centre for Doctoral Training, ISTM
(3rd Prize in the ISTM Blog Post Competition 2016)

Link Found Between Pre-Eclampsia and Diabetes Later in Life

Research led by ISTM and published this week in Diabetologia (the journal of the European Association for the Study of Diabetes) has identified a new link between pre-eclampsia in pregnancy and the development of diabetes in later life.

The condition, which results in high blood pressure and protein in the mothers’ urine, affects 5-8% of pregnancies and is the most common cause of severe perinatal ill health. The study showed that pre-eclampsia is independently associated with a two-fold increase in future diabetes. This increased risk occurs from less than 1 year after delivery of the baby and persisted to over 10 years after birth.

Dr Pensee Wu, ISTM

Dr Pensee Wu, Lecturer in Obstetrics and Gynaecology at ISTM, is the first author of this publication and said:

“This study highlights the importance of clinical risk assessment and follow-up for the future development of diabetes in women with pre-eclampsia. Understanding of health conditions during pregnancy and their impact on health over a woman’s life is vital in the prevention of conditions such as diabetes.

“Ensuring women are screened regularly and take preventative measures through diet and exercise could help reduce the number of women who later contract diabetes after experiencing pre-eclampsia during pregnancy.”

The study involved a systematic review of research over the past 10 years, much of which was conflicting about the impact of pre-eclampsia later in life.

The understanding of the long term impact of women’s health following pre-eclampsia is however growing. The American Heart Association has linked pre-eclampsia to longer term cardiac conditions.

“Diabetes is a multi-organ condition. If we can prevent it from developing early on, it could dramatically reduce the risks of serious health issues later in life for women after birth” says Dr Wu.

Researchers hope that dissemination of this study to clinicians, particularly those in Primary Care health provision, will inform practice and longer term preventative measures.

As well as being a Lecturer in Obstetrics and Gynaecology at ISTM, Dr Pensee Wu is also an Honorary Consultant Obstetrician and Fetal Medicine Subspecialist at the University Hospital of North Midlands (UHNM).

This study was supported by a grant from the North Staffs Heart Committee and the National Institute for Health Research Academic Clinical Fellowships. This study was a collaboration between UHNM Academic Obstetrics and Gynaecology, Keele Cardiovascular Research Group, Institute for Primary Care and Health Sciences at Keele University and the Institute of Applied Health Sciences at the University of Aberdeen. The authors are: Pensee Wu, Chun Shing Kwok, Randula Haththotuwa, Rafail Kotronias, Aswin Babu, Anthony Fryer, Phyo Myint, Carolyn Chew-Graham and Mamas Mamas.

ISTM Translate - Issue 4: Nanopharmaceutics

The latest issue of the ISTM Translate magazine is now available in digital and print format. The theme focus for this issue is nanopharmaceutics.

There are contributions from Dr Clare Hoskins, Dr Anthony Curtis, as well as other members of the Keele Nanopharmaceutics Group.  Articles include...

· Medicine at the small scale:  The exponential growth in nanopharmaceutics

· Programming death in cancer cells:  Novel technologies improving long-term prognosis

· The great solubility challenge:  Investigating potential in targeted drug delivery

· Theranostic Advances:  The knowledge and fabrication of nanotechnologies

· Nanopharmaceutics Symposium:  Successful second annual event at Keele University

· Spotlight:  The people behind ISTM

· Public engagement:  Bringing research closer to people

· Taking advantage of change:  A new streamlined Institute structure for ISTM

By clicking here you can access the online digital version of Translate Issue 4. Alternatively you can request a paper copy by contacting:
Joseph Clarke
+44 (0)1782 674998 | j.clarke@keele.ac.uk

Building bridges through Science: David Mottershead attends international congress in Iran

Written by Dr David Mottershead (Lecturer in Biochemistry & Cell Biology, ISTM)
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Making new friends from the Congress.  (David is second from right).

As a result of an email I received on the 20th of June this year inviting me to speak at the Royan International Twin Congress (August 31-September 2) in Tehran, Iran, I was plunged into quite an adventure. The Royan International Twin Congress has been held every year since the first meeting in September 2000. This year’s meeting saw the joint holding of the 17th Congress on Reproductive Biomedicine and the 12th Congress on Stem Cell Biology & Technology, both supported and organized by the Royan Institute in Tehran. This being my first trip to the middle east meant that a new and unusual experience was assured. 

Ceiling of the Tomb of Hafez, Shiraz.

The meeting itself reflects the nature and makeup of the Royan (in Persian “royan” means embryo) Institute itself, which has Divisions devoted to reproductive biomedicine, stem cell biology and biotechnology. The congress itself has the two streams of reproductive biomedicine and stem cell biology running concurrently. This enabled one to pick and choose between both session streams, and although I found myself predominantly within the reproductive stream, I did cross over for a number of very interesting presentations within the stem cell stream as well. International speakers from across the world were in attendance (UK, USA, Austria, China, Netherlands, Australia, Germany, Denmark, Sweden, Switzerland, Italy, for example). Apart from Keynote Lectures and Award Lectures, there were the various invited speakers talks, short oral presentations, poster sessions and exhibitions. The sessions of particular interest to me were, Animal Biotechnology, Tissue Engineering in Reproductive Sciences, and Regenerative Medicine, Novel Discoveries.

Tombs of kings past, Naqsh-e-Rostam.

The conference organizers looked after the invited speakers extremely well, we were never short of food/refreshments at the venue and every evening we were taken to see sites in Tehran and out to eat, enabling us to experience the magnificent local cuisine. From my own point of view, the congress was extremely productive with good discussions/connections established between myself and two separate labs at the Royan Institute which should lead to ongoing collaborations. For all the invited speakers a 2 day tour of highlights of Iran was offered which I participated in, enabling one to experience the history of the country and see some amazing sites. First we flew South to Shiraz, a distance of 700 km. We arrived late and would not have time to get to know Shiraz well, but did visit the Tomb of Hafez, one of Iran’s famous and revered poets who lived in the 14th century (1325-1389). Upon leaving Shiraz by bus we started our long trip back North to Tehran. Our first stop 70 kms from Shiraz was at a series of tombs cut into the cliff side where ancient kings were buried. The site is known as Naqsh-e Rostam and had a distinctly “Indiana Jones” feel to it, certainly it transported one back in time. Not far from this site we stopped at the ruins of the ancient city of Persepolis which was the ceremonial capital of the Achaemenid Empire (550–330 BC). Here various kings and statesmen from around the world would come to greet the Iranian king, a must see site on any trip to Iran. Finally we arrived at the city of Esfahan (also spelt Isfahan) about 300 km South of Tehran. Esfahan is the 3rd largest city in Iran at nearly 2 million people. The main attraction is the large Naghsh-e-Jahan square constructed between 1598 and 1629. Around the square are located three mosques and what seems like hundreds of shops selling the most beautiful craftworks. I could not do this area justice in this short visit, however, given the collaborative links which I believe will be established, it may well not be my last.

One of the mosques at Naghsh-e-Jahan Square, Esfahan.

Dr Patricia Wright awarded prestigious PhD prize

I was surprised and delighted to find a couple of weeks ago that I had been awarded the Vice-Chancellor’s PhD Prize 2016 for the best postgraduate research at the University of Greenwich.

My programme of research was Understanding MS/MS Fragmentation of Small Molecular Weight Molecules. I proved the hypothesis that protonation altered the conformation of molecules such that some bonds were weakened and more susceptible to cleavage. This impacts all scientists who use MS/MS for structural elucidation in that quantum chemistry can now be used a tool in assignment of ion structures. I am pleased to have been able to make a real difference to UK science.

I loved every minute of my PhD, particularly the stimulating scientific discussions with my supervisor Professor Frank Pullen and computational chemistry expert Alexander Alex. I also enjoyed getting to grips with quantum chemistry.

Thanks to the support and encouragement of the staff in the Greenwich University Department of Pharmaceutical, Chemical and Environmental Sciences, I managed to take my viva voce one day before the third anniversary of starting my research programme, passing with no changes required to my thesis and having published five research papers and two editorials. I am also grateful for the tolerance of my family who put up with me working all the time!

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Patricia has since come to work at Keele University for ISTM in the breath analysis research group pioneered by Professor David Smith FRS.

How brain implants can let paralysed people move again

Dimitra Blana, Keele University and Andrew Jackson, Newcastle University
Something as simple as picking up a cup of tea requires an awful lot of action from your body. Your arm muscles fire to move your arm towards the cup. Your finger muscles fire to open your hand then bend your fingers around the handle. Your shoulder muscles keep your arm from popping out of your shoulder and your core muscles make sure you don’t tip over because of the extra weight of the cup. All these muscles have to fire in a precise and coordinated manner, and yet your only conscious effort is the thought: “I know: tea!”
This is why enabling a paralysed limb to move again is so difficult. Most paralysed muscles can still work, but their communication with the brain has been lost, so they are not receiving instructions to fire. We can’t yet repair damage to the spinal cord so one solution is to bypass it and provide the instructions to the muscles artificially. And thanks to the development of technology for reading and interpreting brain activity, these instructions could one day come direct from a patient’s mind.
We can make paralysed muscles fire by stimulating them with electrodes placed inside the muscles or around the nerves that supply them, a technique known as functional electrical stimulation (FES). As well as helping paralysed people move, it is also used to restore bladder function, produce effective coughing and provide pain relief. It is a fascinating technology that can make a big difference to the lives of people with spinal cord injury.
Dimitra Blana and her colleagues at Keele are working on how to match this technology with the complex set of instructions needed to operate an arm. If you want to pick up that cup of tea, which muscles need to fire, when and by how much? The firing instructions are complicated, and not just because of the large number of core, shoulder, arm and finger muscles involved. As you slowly drink your tea, those instructions change, because the weight of the cup changes. To do something different, like scratch your nose, the instructions are completely different.
Instead of just trying out various firing patterns on the paralysed muscles in the hope of finding one that works, you can use computer models of the musculoskeletal system to calculate them. These models are mathematical descriptions of how muscles, bones and joints act and interact during movement. In the simulations, you can make muscles stronger or weaker, “paralysed” or “externally stimulated”. You can test different firing patterns quickly and safely, and you can make the models pick up their tea cups over and over again – sometimes more successfully than others.

Modelling the muscles

To test the technology, the team at Keele is working with the Cleveland FES Center in the US, where they implant up to 24 electrodes into the muscles and nerves of research participants. They use modelling to decide where to place the electrodes because there are more paralysed muscles than electrodes in current FES systems.
If you have to choose, is it better to stimulate the subscapularis or the supraspinatus? If you stimulate the axillary nerve, should you place the electrode before or after the branch to the teres minor? To answer these difficult questions, they run simulations with different sets of electrodes and choose the one that allows the computer models to make the most effective movements.

Currently, the team is working on the shoulder, which is stabilised by a group of muscles called the rotator cuff. If you get the firing instructions for the arm wrong, it might reach for the soup spoon instead of the butter knife. If you get the instructions to the rotator cuff wrong, the arm might pop out of the shoulder. It is not a good look for the computer models, but they don’t complain. Research participants would be less forgiving.
Knowing how to activate paralysed muscles to produce useful movements like grasping is only half of the problem. We also need to know when to activate the muscles, for example when the user wants to pick up an object. One possibility is to read this information directly from the brain. Recently, researchers in the US used an implant to listen to individual cells in the brain of a paralysed individual. Because different movements are associated with different patterns of brain activity, the participant was able to select one of six pre-programmed movements that were then generated by stimulation of hand muscles.

Reading the brain

This was an exciting step forward for the field of neural prosthetics, but many challenges remain. Ideally brain implants need to last for many decades – currently it is difficult to record the same signals even over several weeks so these systems need to be recalibrated regularly. Using new implant designs or different brain signals may improve long-term stability.
Also, implants listen only to a small proportion of the millions of cells that control our limbs, so the range of movements that can be read out is limited. However, brain control of robotic limbs with multiple degrees-of-freedom (movement, rotation and grasping) has been achieved and the capabilities of this technology are advancing rapidly.
Finally, the smooth, effortless movements that we usually take for granted are guided by rich sensory feedback that tells us where our arms are in space and when our fingertips are touching objects. However, these signals can also be lost after injury so researchers are working on brain implants that may one day restore sensation as well as movement.
Some scientists are speculating that brain-reading technology could help able-bodied individuals to communicate more efficiently with computers, mobile phones and even directly to other brains. However, this remains the realm of science fiction whereas brain control for medical applications is rapidly becoming clinical reality.

Dimitra Blana, Research Fellow in Biomedical Engineering, Keele University and Andrew Jackson, Wellcome Trust Senior Research Fellow, Newcastle University
This article was originally published on The Conversation. Read the original article.

Tissue "archeology": Dating collagen fibers

ISTM recently ran a blog writing competition that was open to PhD students and young researchers with a view to improving their lay-writing skills and helping ISTM to play a greater role in the public dissemination of its research. After concluding the competition we will be publishing each entry in turn over the coming months. The 2nd prize winner of our competition was Homayemem Weli, a PhD student in Cell and Tissue Engineering at ISTM. 

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Walking through the streets of London in mid-summer, I couldn’t help but notice its beautiful 'ornaments' of modern architecture, such as the "Gherkin" or the "Walkie-Talkie". Imposing as these are, they attract less curiosity than Wiltshire’s Stonehenge.

A graceful and strong modern building speaks of a firm foundation and good design, but an ancient monument raises questions such as "when", "how" and "why". Some of us recall the creation of the London skyscrapers - having possibly witnessed it - but I dare say none of us witnessed the making of Stonehenge! Instead, we rely on archaeological research to answer questions about its origin, age and significance. This ‘discovery science’ compels us to find out why things are the way they are, and go from the known to the unknown.

Stonehenge by David Ball - www.davidball.net

Keen to unravel the unknown, I set out to study an aspect of why people age. My focus was on women and what happens to their vaginal and skin tissues before and after pregnancy. Adorned with laboratory clothing and gloves, as though performing carbon dating on the standing stones of Stonehenge, I examined the structure of collagen fibres and cross-links within the tissues. Collagen is a protein that supports structures within the body. Cross-links are bonds formed between collagen groups (called fibres) or between chemical substances such as amino acids or reducing sugars. The larger the number of certain cross-links within the collagen fibres, the older the fibres. Collagen 'cross-link dating' can separate old fibres from young ones.

I tested two groups of tissues, pregnant and non-pregnant, of similar biological ages. I separated a particular cross-link, pentosidine, which is a known marker of tissue ageing, from the tissue solutions with liquid chromatography (a method for identifying and separating substances present within a solution). I noted the amount of pentosidine in each tissue, and compared the values.

This process of 'cross-link dating' separated the age-matched tissues into two groups – ‘old’ and ‘young’. Before pregnancy, tissues were ‘older’, but after pregnancy, they appeared ‘younger’. During pregnancy, the signs of ageing appeared to reverse! 

Studying further, I discovered this was linked with a rise of a potent antioxidant, glyoxalase I, in the tissues during pregnancy. Antioxidants such as glyoxalase I protect the body cells from molecules that could cause damage or promote ageing.

Antioxidant glyoxalase I enzyme expression in vaginal tissues during (left) and after (right) pregnancy. Green glow, clearly visible within the pregnant tissue, represents presence of the antioxidant enzyme. The pregnant tissues had more antioxidant. 

Oestrogen, a well-known pregnancy hormone, influenced the amount of the antioxidant in the tissues. I found higher oestrogen levels in pregnant tissues as shown in the images below. This implied pregnancy resulted in higher oestrogen and antioxidant levels.

Oestrogen receptor expression in vaginal tissues during (left) and after (right) pregnancy. Red dots signify oestrogen activity within the tissue and show raised level of oestrogen during pregnancy.

I concluded that oestrogen influences the ‘age’ of collagen fibres of the skin and vaginal wall by increasing the antioxidant glyoxalase I. Rise in oestrogen as seen in pregnancy leads to rise in the enzyme, subsequently retarding collagen fibre ageing within the tissues. In this way, pregnancy results in younger appearing tissues.

Oestrogen is a female reproductive hormone that changes throughout the life of a woman. It increases in quantity during pregnancy and reduces as women grow older, finally reaching its lowest levels in menopause. My finding shows that pregnancy may retard this ageing process in the vaginal and skin tissues of women. A previous study noted a reduction in similar ageing cross-links within blood vessels also in association with higher oestrogen levels, suggesting that this effect may exist in many body tissues.

By studying pregnancy, I discovered a relationship between oestrogen, an antioxidant, and the ‘age’ of collagen fibres (change of the structure) in skin and vaginal tissues.

New knowledge can be gained from investigating age-old body processes. It's always worth asking "when", "how" and "why”!

Written by Homayemem Weli, PhD Student, ISTM
(2nd Prize in the ISTM Blog Post Competition 2016)