Category Archives: interesting topics

Leukaemia and Diabetes Drugs?

Today, an interesting news story caught my eye regarding Leukaemia. Leukaemia is a cancer which usually originates from bone marrow, and leads to the production of abnormal white blood cells [1]. It is a disease categorised by the type of white blood cell it affects, which are the myeloid cells of lymphatic cells [1].

This poses an issue when it comes to treatment options, as targeting unhealthy, harmful mutated cells in the bone marrow, can also damage healthy cells – both white and red blood cells. There are several treatment options, including chemotherapy, biological therapy, targeted therapy, radiation therapy and stem cell transplants [2]. Biological therapy helps a patients’ immune system recognise leukaemia cells, and targeted therapy uses drugs which specifically target certain weaknesses within cancer cells [2]. While these options have a, rightfully, strong emphasis on target leukaemia cells, they can also often damage red blood cells – causing fatigue, dizziness, anaemia, and a wide range of side affects [3].

A recent study, published in ‘Nature Cell Biology’ takes a different approach, considering the ‘entire bone marrow as an ecosystem’ [3] and not just targeting diseased cells. It was found that Leukaemia suppresses the cells which store fat in the body, causing the maturation of red blood cells to stop, as their stem cells dysfunction [3].

What is particularly interesting, is that a drug, commonly used to treat type-2 diabetes, was shown to have positive effects. PPAR-gamma, helps to restore the fat cells in the bone marrow – thus, restoring healthy red blood cell development and minimising the leukaemia’s growth [3]. By changing the environment that the cancer ‘lives’ in, it allowed healthy cells to thrive and, if you will, ’outcompete’ the cancerous cells, suppressing their growth.

I think this has very exiting prospects for cancer treatment in the future, and is an approach which can be applied to many different therapies and treatment options. Looking at a broader image, organ or system could raise treatment options, which have no previously been considered.

Book Review – Madness and Memory

On the eve of AS exams, I have just finished reading ‘Madness and Memory’ by Stanley B. Prisoner, M.D. It is a book I found when researching for my EPQ and bought back in February, however because of its scientific content, it has taken me a while to get my head around and work through.

Despite this however, I have found it an incredibly interesting book, which appealed to both my love of science and medicine. It is written almost like a diary, a documentation of the events which led to the discovery of prions but explained for those without a science degree (definitely aiding my understanding a huge amount!) making it much more of an easy read.

To me this book highlighted the sheer amount of dedication which goes into research, not something I aspire to do but definitely something I respect. It reflects the skepticisms of new ideas and the rivalries between scientists in bucketloads – a perfect balance of drama and science. The transformation of an unconventional hypothesis – that of protein only (prion) diseases – into what I think is one of the greatest discoveries since the DNA double helix.

I would recommend this book to any budding medical professional or scientist not only because of the way it is written but largely down to its content. Prions are incredibly interesting diseases, and further discoveries could help unravel the unknown about brain diseases – mad cow, Alzheimers, Parkinson’s and Lou Gehrig’s. The debate about the origins of such diseases is what I intend to focus my EPQ on, are they due to cannibalism, food supplements or BSE infected beef? This book has certainly succeeded in piquing my interest in the topic further, and I can’t wait to pick my research up again in a months time, after my exams.

The amazon link to ‘Madness and Memory’ is: https://www.amazon.co.uk/d/Books/Madness-Memory-Discovery-Prions-Biological-Principle-Disease/0300216904/ref=sr_1_1?ie=UTF8&qid=1494614063&sr=8-1&keywords=madness+and+memory

Nature’s Medicine Cabinet – from Root to Remedy lecture

At the Cambridge Medicine Masterclass earlier this month, I listened to a lecture led by Sonja Dunbar, and was truly intrigued. If I’m honest, it was the lecture I thought I would be least interested in, as I expected it to focus on herbal remedies and the likes, yet it was much more medicine focused.

66% of all drugs have their origins in nature, and infant 80% of people in underdeveloped countries rely on traditional remedies from plants. Thus, their used simply cannot be ignored. Yet, what was a really interesting proposition was why are so many compounds in plants beneficial to humans? It is absurd to think that plants exist for our benefit, there are abundant defences to stop us using them. Spikes, thorns, bristles and chemical poisons all with the intention of helping the plant live longer, and protect the plants form those who are likely to eat it. A key example of this is the classic stinging nettle. These contain histamine, responsible for the itching felt after a sting and acetylcholine, a neurotransmitter. These are contained in a trichome, a specialised ‘hair’ in plants which is very similar to a hollow needle. Alongside this, stinging nettles contain Leukotriene, which promotes information and causes blood plasma to leak out of the membrane and lysosomes to swell, and serotonin. All of these chemicals are pumped in you your body when you are stung by a nettle.

Holly

This leads us to the scarcity-accessibility hypothesis, where a plant in an environment where it is more likely to be eaten, for example when other plants are scarce is likely to have the most defences. Examples of such plants  are Holly and cacti, both of which have visible mechanical defences – holly with its spiked leaves, and cacti with their needle-

cacti-needles_3cc3cf1c0f513010like spikes.

An interesting example of a plant which attempts to deter you form eating it, is the chilli. Chill is detected by TRPVI, the same receptor as vanilla, and vanillin and capsaicin are in fact structurally very similar. However, vanillin cannot get through the cell membrane, yet capsaicin can, and therefore binds to the receptor and tigers the brain into thinking you’ve eaten something hot. For most humans, this would not be a pleasurable experience and would put you off eating a chilli again. However, it gets better. Chilli’s receive no benefit from being eaten by mammals, as we grind and crunch seeds up due to our molars. Their seeds are therefore broken apart and cannot germinate to produce more plants. Although, birds eat chilli’s and don’t seem to find them hot. Why? Because birds don’t crush or grind the seeds, simply pass them through their digestive system and disperse them. They can travel great distances in a short space of time meaning that very little competition between the plants remains, and so birds do not find chilli’s hot, as the plant benefits from being consumed.

So, what are some examples of plants used in medicine? Foxgloves, contain digitoxin which helps to controlyour heart rate. It is a cardiac glycoside which interferes with sodium-potassium pumps, calcium ions and polarisation. In a high dose, it causes irregular heart rates, yet in a low does, it is very useful. Thus, from digitoxdigoxinstructurein digoxin has been developed, with less side affects and thus less associated dangers than the ‘pure’ substance, but with a very similar chemical structure.

Similarly, Aloe Vera contains 98.5% water, mannose-6-phosphate sugars and a collagen triple helix. It can be used in the treatment of thermal and radiation burns. It has been known to reduce swelling, stimulate faster tissue synthesis and help keep the wound clean and hydrated due to the high water content. Thus, it is used in many suncreams, after suns and in a gel to help prevent wounds from infection.

The lecture also spoke about the 2015 Nobel Prize in physiology or medicine. In 2013 there were 198 million cases of malaria, and is a disease which can easily escape detection due to the life cycle of the parasite. Theparasite enters liver cells where it can replicate for 2 weeks without detection. Eventually, the liver cells rupture and release the parasite, which consequently goes on to infect red blood cells. Here, the parasite escapes detection by wrapping itself in the cell membranes of cells from the organism – which will not be recognised as something harmful by the immune system. Cinchona  is an example of an early malaria remedy, which was so heavily sought after the plant nearly went extinct. Artemisinin also treats the fever of malaria, and with cold extraction, reduces 100% of the parasite load in monkeys and mice – incredible. Consequently, the death toll form malaria in the past 15 years has declined by 50%, and it is great to see the Nobel Prize being awarded for a medicine being developed for disease in underdeveloped/developing countries. This is because it takes around 12 years and £1.2 billion to take a drug to market, not something which is affordable to such counties, but malaria is a disease which takes millions of lives, and so any advancements could save countless lives.

What I learnt from this lecture is that biodiversity mattersin the hunt for new drugs. There are still plants we don’t know exist, and plants we do know exist but don’t yet recognise their uses. In destroying the biodiversity of our world, for example by deforestation, we could potentially be destroying cures for diseases. The ecology of the world we life in is important to allow us to survive, and while plants don’t exist for out benefit, they are incredibly useful.

(Source: Sonja Dunbar, Nature’s Medicine Cabinet Lecture, Cambridge University)

A Pharmaceutical Lecture by Gwenan White

Hello!! A couple of days ago I attended a pharmaceutical based lecture at my school, spoken by a woman who works for the company AbbVie, a comparatively small company specialising in virology, immunology, neuroscience and oncology. It was far more interesting and relevant to me than I initially thought it might be, and I took away some key lessons which I thought I would share with you.

It typically takes around 12 years to bring a medicine to life – over a decade of isolating compounds and mixing constituents and clinical trials. What interested me within this process was the use of animal testing. Animal rights are something I feel strongly about and if I’m honest, I’ve always been opposed to their use in science. However, recently I attended a lecture on the ‘naked mole rat’ (hopefully a blog post to follow!) and then this lecture, which has made me consider the benefits and boundaries of using animals in science. While I won’t dwell on the use of the naked mole rat too much as it is something I’d like to write about later, it was a talk which demonstrated to me a clear ethical and moral use of animals in research. In the pharmaceutical industry however, it is not always clear how these animals may react to the drugs within their systems. Although, it was emphasised to me that as few a animals as possible are used with the most effecting but least affective (in terms of side affects) treatment option primarily. Or surrogate models can be used preventing the need for animals. This showed me the diverse range of steps needed to take a medicine to market, and that medicines must not only be effective and ethical but also cost effective.

The ethos of the AbbVie  in the talk was that they aim to combine the expertise and stability of traditional pharma with the focus, culture and innovative spirit of biotech. This really summed up the state of modern science and medicine for me, we are in a stage where we a gradually moving away from the reliable treatments and options for those which may be slightly more risky but give patients better quality of life post treatment. For instance, when watching the BBC documentary ‘Hospital’ last week I was captivated by the innovative treatment of a 98 year old man. He first, had a compressed heart valve inserted into his heart through a blood vessel in his leg, which was then synchronised with the contraction of his heart using a screen. However, the incredible surgical techniques didn’t stop there, he later had a wire mesh inserted into an artery which led to his brain to remove a clot causing him a stroke and possible brain damage. This being a thrombectomy, which if carried out within 6 hours of a stroke results in full blood flow and a reduced risk of brain damage. Similarly, in the same documentary a new treatment method was used to treat an 18 year old girl with Sickle Cell disease, where her immune system was depleted using chemotherapy and radiotherapy allowing her to engraft bone marrow with a match of only 50%. This is an incredible feat. Linking this back to the lecture, it is through combining new ideas and treatment methods with the stability of old ones which medicine can and is advancing.

Like much of the news these days, the talk did also mention that out current healthcare system is not sustainable – we have an ageing population and more than 1/4 of people in the UK have a chronic illness. All of which need treatment and all of which costs money. A statistic which was raised is that every 36 hours 1,000,000 people pass through the NHS, and we do not have a healthcare system which can deal with that demand. What we do have however, is new means of empowering patients to look after themselves – who hasn’t seen an advert for an online GP? Or advice from the NHS website? What is crucial is that doctors need recognise the role of the patient in their own treatment – diet and lifestyle choice can hugely influence what treatment a person may later need, but also knowing when and when not to see a doctor of GP is crucial. The NHS does not, essentially, have time to waste. Having said that, there should be no ‘fear of finding out’ what the doctor has to say, and people should not avoid the GP Surgery because they are scared they are ill – they should act quickly and potentially save their own live, or give themselves years. If not, at least just peace of mind.

So these are some of the key ideas I took from a pharmaceutical lecture I thought would just be about the development of drugs, which was actually much more patient focused for an industry which is not allowed direct patient contact – charities and organisations on patient’s behalf must be used instead. Therefore, I would encourage everyone to attend some science or medicine based lectures, and not to be afraid to take notes. Taking notes is what I’ve found has really allowed me to write up and reflect on what I’ve learnt, and that’s definitely worth more than a few snide comments. I hope you’ve found this interesting and hopefully I will write more reflections on lectures in the future.