Last week was another superb week for circadian research in the Molecular and Cellular Therapeutics Department. The Curtis Laboratory published our first big paper on the immune body clock in Nature Communications. This study originated back in 2013. I was still a postdoc in Prof. Luke O’Neills laboratory at Trinity College and was intrigued by some of the studies that showed that multiple sclerosis (MS) was affected by the circadian disruption. A key study showed that teenagers who work shift work before the age of 18 are more susceptible to multiple sclerosis in later life. I wondered if we would see any differences in multiple sclerosis if we disturbed the immune body clock. I approached Prof. Kingston Mills also at Trinity College, who is one of the world leaders of multiple sclerosis and has a key mouse model that recapitulates certain features of MS, called experimental autoimmune encephalomyelitis (EAE). The first experiment we conducted was to see if a mouse which does not have the molecular clock in macrophages was more susceptible to disease, and low and behold it was! This project was driven by one of the most talented researchers that I have ever had the pleasure of working with, Dr. Caroline Sutton, who is a senior postdoctoral fellow in Prof. Mills lab. This project is a great example of collaboration between multiple labs, Mills, O’Neill and my own new group here at RCSI.
And if that wasn’t enough! We also hosted the circadian expert Prof. Qing-jun Meng for our second institutional seminar series on Thursday. Prof. Meng is a world expert on clocks in the musculoskeletal system at University of Manchester. I met Qing-jun in 2013, and have followed his research intensely. He has made seminal discoveries on the impact of the clock on cartilage and invertebral disk function and how this leads to diseases of ageing, such as osteoarthritis and lower back pain. He had the audience enthralled for an hour with his rhythmic images of cells glowing with 24-hour rhythms, and his use of Google searches. It was an absolute pleasure to have Qing-jun with us for the day, and I hope that we can have him back again in the near future.
Some news features on the article can be found here:
On November 14th, we welcomed almost 50 secondary school students at our Department for Lab Safari. The event was designed to encourage young people to consider a career in Science, Technology, Engineering, Maths and Medicine through hands-on experience and demonstrations prepared by our researchers. We developed 6 different workstations focused on Cancer biology and biomarkers, Drug Discovery, Multiple Sclerosis, Human Genetics and Immunology/Body clock
The event was opened by Prof. Tracy Robson, Head of MCT, sharing her career path in research and lessons that she learnt. Dr Avril Hutch, Head of RSCI Equality and Diversity Unit, also spoke about stereotypes in STEMM careers and having an awareness of unconscious bias.
Our workstation was led by Caragh Stapleton, Katherine Benson and Edmund Gilbert, centered around human genetics. Our activity set out to teach participants about inherited traits and demonstrate how variation in our DNA influences our physical attributes. We investigated a number of traits including PTC taster (using PTC taste strips), colour blindness, widows peak, tongue rolling, attached earlobes, bent little finger, eye colour and red hair. Each participant noted whether or not they had the given trait and we then discussed the hypotheses of the genetic variants influencing the different traits.
Our workstation was led by Olga Piskareva and John Nolan. We explained the concept of biomarkers and the importance of discovering novel biomarkers for neuroblastoma, a childhood malignancy. Various chromosomal aberrations can be biomarkers of neuroblastoma aggressiveness. One of the strongest predictors of rapid neuroblastoma progression is MYCN status. We selected several neuroblastoma cell lines with known MYCN status providing a good illustration of biomarker’s quantity. Using immunodetection, we visualised the differences in the MYCN presence.
Our workstation was led by Annie Curtis, Mariana Patricia Cervantes Silva, George Timmons and Cathy Wyse. The theme of our activity was on the body clock and immune function. We discussed with the students why they get jet lag and what that has to do with their body clock. Students then moved to the first station where they got a chance to add colouring to macrophages, so we had red, yellow, blue and green macrophages and were able to look at their coloured macrophages under a microscope. Then they moved to the next station where they got to see the master clock which resides in the hypothalamus of the brain under a microscope. Finally, we displayed some images of activated macrophages and explained their function.
Cancer Cell Biology
Our workstation lead by Sudipto Das, Gillian Moore and Stephanie Annett, focused on showcasing the various laboratory-based approaches applied regularly to identify and investigate novel gene or protein-based biomarkers of cancer progression. Within our workstation, we highlighted three key areas including how samples following biopsy from a cancer patient are used to construct tissue microarrays which are used for assessing the importance of a certain protein in cancer. This was followed by demonstrating a particular tissue culture-based method used to study anti-cancer properties of drugs and finally displaying an array of microscopic images of blood vessels developing in a given tumour.
Our workstation was led by Claire McCoy, Remsha Afzal and Conor Duffy. The research focus at our lab safari station was Multiple Sclerosis (MS). We explained how the causes of MS are unknown, but that it is characterised by an influx of immune cells into the brain and spinal cord. Our research aims to investigate one type of immune cell called the macrophage. We aim to understand the damage macrophages cause in MS and if we can reverse this to provide an alternative tool for MS therapeutics. We really enjoyed explaining our research at the Lab Safari, where we showed students how MS impacts on brain function and showed them examples of activated macrophages under the microscope.
Our workstation was led by Dermot Cox and Padraig Norton. Students were given a brief history of drug discovery. Then they were introduced to the basic concepts of how a drug binds to its target and the different ways in which a drug can bind. Students were then shown a demonstration of molecular docking on a computer whereby a small molecule, or drug candidate, was virtually docked into a target binding site using the software.
The event was led by Dr Maria Morgan, Anne Grady, Prof. Tracy Robson, Dr Olga Piskareva and John O’Brien. Guides on the evening included Olwen Foley, Camille Hurley, Mary Ledwith, Seamus McDonald and Shane O’Grady.
Last Monday while in Amsterdam with my Mam and two sisters, a friend of mine sent a text to let me know that the 2017 Nobel Laureates in Physiology and Medicine were Hall, Rosbash and Young. They were awarded the Nobel for their work in identifying the key genes that create circadian or body clock rhythms in the fruit fly. My feet literally were stuck to the ground, it was thrilling to know that these gentlemen would get the recognition that they so deserve, but also what this will mean for the field of science that I am so passionate about. The body clock is the molecular timekeeping system that exists in practically every organism on the earth and in every cell in our body. Simply put, it allows the cell to tell what time of day it is. Why is that important? We live on a spinning planet and because of the earth’s rotation to the sun, all life on earth has been subjected to daily periods of light and heat, dark and cold. The body clock allows us to anticipate and respond to these 24-hour predictable environmental changes and synchronises our physiology to it. For example, the body clock increases cortisol levels in the body ahead of awakening, this helps us to become active once we wake. The body clock also increases expression of digestive enzymes in the intestinal tract during daylight hours (this is why curry chips at 3am is never a great idea!).
Back in the 80’s Hall, Rosbash and Young independently isolated a gene called Period, they showed how the gene encodes a protein PER that builds up in cells at night and degrades during the day. This daily rise and fall of PER essentially allow the cell to track time of day. How thrilling it must have been for them to observe this daily change in the mRNA levels of Period gene (Figure 1- black line), all that is changing along the x-axis is the time of day.
So what does this mean three decades later? We have made great strides in understanding how the molecular clock works. We now know that the clock keeps time by a series of transcriptional-translational feedback loops. We also know that the clock controls 40% of all coding genes within the body. The body clock controls all aspects of our physiology from metabolism to immunity.
Many diseases, such as osteoarthritis and cardiovascular disease, are highly time of day dependent. Moreover, it appears that disruption of our body clocks, caused by our non-stop 24/7 lifestyle and exposure to artificial light at all times of day, is partly responsible for the increase in chronic inflammatory diseases. Unfortunately, most cell culture systems are not synchronized with the time of day, and this, in my opinion, is one of the main reasons that many researchers unknowingly neglect this field. Finally, we are making great strides in attempting to time specific treatments to the right time of day, an area called chronotherapy. Therefore, it is my hope that this increased awareness of the body clock will bring more researchers into this fascinating field. If we don’t fully understand how our body clock controls physiology and disease we will certainly be left in the dark.
Annie Curtis is a Research Lecturer and runs the Immune Clock laboratory at MCT and is fascinated by all things body clock related.
She was awarded a prestigious L’Oréal-UNESCO For Women in Science 2017 Fellowship at a ceremony held at the Royal Society in London on May 5th.
She was one of five winners of these fellowships and the only Irish winner this year. The fellowship will support her research into understanding the precise mechanisms by which the body clock restrains inflammation from a key immune cell called the macrophage.
Last week’s departmental talks encompassed a Deep Dive into Clock biology in Macrophages affecting the Inflammatory Response. This area is the focus of the Immune-Clock laboratory of Dr. Annie Curtis, a recent recruit to RCSI.
Jamie Early (PhD student of the Curtis Lab) currently residing in the Luke O’Neill Laboratory presented his findings on the role of the circadian clock in suppressing inflammation in macrophages and if the anti-oxidant transcription factor and redox sensor NRF2 plays a role. His talk was titled ‘The macrophage clock is a key controller of the anti-oxidant and inflammatory response via the transcription factor Nrf2’.
Second up, we had Mariana Cervantes (PhD student and visiting scientist from the Instituto Politecnico Nacional (IPN) in Mexico) present her talk titled ‘The macrophage clock is having a profound impact on mitochondrial dynamics- what are the implications for inflammation?’
Mariana is interested in how mitochondria alter their morphology, either fusing together to form networks or fragmenting into smaller units termed fission. She is trying to uncover if the clock is regulating this process and if so what are the implications for the inflammatory response.
Our Immune-clock laboratory has a real interest in metabolism and how alterations in metabolic pathways termed “metabolic reprogramming” can shape the type of immune response. This area called “Immunometabolism” has exploded in the last 5 years, and the implications are massive. It appears that macrophages use one metabolic pathway to become highly proinflammatory and another metabolic pathway to resolve inflammation and promote wound healing. So why is our laboratory so interested in this? Well, if you think about daily changes in our environment, the two biggest are the sleep/wake cycle and the other is feeding/fasting. It is now clear that clocks in metabolic tissues like the liver/pancreas/adipose tissue prepare the body to deal with this daily rhythm in feeding/fasting. Based on this, our interest is to figure out if the clock within macrophages is somehow altering its metabolism over the course of the day and is that leading to changes in macrophage function, particularly the inflammatory response.
Body clocks tend to garner quite a bit of attention from the media. Folks are obsessed with sleep, either they cant get enough or they are getting too much, and all of us can relate to the symptoms of jet lag and morning versus evening types. Therefore it’s a great topic to discuss with wider audiences. I really enjoy chatting with people about the implications of our internal timing system and that research now shows that living in synchrony with your body clock can improve overall health. For the SFI Science week I was asked to provide an interview to the Daily Star called “The Science of Sleep Explained”. I was also asked to go on the “Alive and Kicking” show on Newstalk Radio with Ciara Kelly, you can listen to the interview: What type of sleeper are you? Are you an owl or a lark?