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Veterinary science used to be just about animal health. But researchers at the Royal Veterinary College are extending their reach into human medicine, using gene analysis and other new techniques to discover the causes of disease in people by studying pets and farm animals.
On a visit to RVC’s Hawkshead campus in rural Hertfordshire (just beyond London’s sprawling suburbs) I heard about animal insights into human afflictions, from diabetes and obesity to muscular dystrophy and cancer.
“Comparative biomedicine and the One Health approach [uniting human, animal and environmental health] encapsulate our aims better than saying we are here for animal health,” says Stuart Reid, RVC principal, whose research background encompasses human and animal epidemiology.
Of course, medical researchers in universities and industry already use animals, mainly mice and rats, on a vast scale to model human disease and test new procedures and drugs. But these lab animals are bred – and, increasingly, genetically modified – for research. The veterinary approach, in contrast, is to use the models that already exist among domesticated animals.
“Companion animals have many of the same diseases as humans,” says Dominic Wells, professor of translational medicine. “For example, if you want to work on type-2 diabetes, cats with the disease have identical physiology to humans.
“We are interested in exploring treatment options that we might not want to try yet in humans,” he adds, “but where there are strong welfare arguments for using them in companion animals. The animals would benefit while providing useful information for humans.”
Wells, who moved to RVC three years ago from Imperial College medical school, is personally immersed in research to find an effective treatment for muscular dystrophy in people. Although pre-clinical studies are currently under way in lab mice, he believes that work in an “intermediate model” – such as dogs or horses that suffer from related neuromuscular disorders – could be useful before clinical trials start in patients.
David Church, RVC vice-principal, points out that pet cats and dogs are very well suited to genetic studies, because their genomes vary much less between individuals than those of people – a consequence of the way they have been domesticated and bred. This homogeneous “genotype” is matched with an extremely varied “phenotype”, making it far easier for researchers to find links between gene defects and disease in cats and dogs than in humans.
RVC researchers are rapidly building up a huge database of pets attending veterinary practices across the UK, which they can match up with genetic information about the animals. It is already clear that on average crossbred dogs live 30 to 40 per cent longer than purebred animals and that smaller dogs live longer than larger ones.
“For every 10kg extra in body weight a dog dies six months sooner on average,” says Church. “We are about to look for the genetic markers for size and longevity in dogs.” He hopes the results will illuminate the search for longevity indicators in people.
“There are still medical researchers who don’t want to leave the lab rodent,” he adds. “We want to convince people that veterinary research provides valuable complementary resources.”
Dirk Werling, RVC immunology professor, is particularly critical of mouse models in studies of vaccines and the immune system. Farm animals are generally much more like people than mice in the way their immune defences respond to pathogens.
Even so, he says, most vaccines for veterinary and human use are still tested in mice – leading some to be abandoned unnecessarily because they do not work in rodents but would be effective in other species, while others fail in clinical trials having worked in mice.
“Funding bodies continue to support vaccine work in mice even when the mouse is not a good model,” adds Werling. “It might be better to spend money to go directly into cattle.”
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Going nuclear: growth in the brain
The best evidence so far for the life-long production of new neurons in the brain comes from an unlikely source: data based on nuclear fallout. The reassuring conclusion is that an average adult makes 1,400 new cells every day in the hippocampus, the brain region crucial for memory and learning.
Scientists at Sweden’s Karolinska Institute and the US Lawrence Livermore National Lab used a form of carbon dating. Levels of the isotope carbon-14 in the atmosphere rose as a result of nuclear tests in 1945-63 then declined after they stopped. The amount of carbon-14 in a cell’s DNA indicates its age.
The researchers analysed the brains of 60 people who had died aged 19 to 92. The results show that neurogenesis continues through adulthood at a rate that declines only modestly into old age.
Other recent research has undermined the old idea that we are born with a fixed number of neurons, which decline gradually through life without new ones growing to take their place. But this study, published in the journal Cell, provides the most direct estimate so far of neural replacement rates – an annual turnover of 1.75 per cent.
“It has long been suspected that depression is related to reduced hippocampal neurogenesis. Our findings suggest that new and more effective antidepressants could potentially be developed to target this process,” says Jonas Frisén of the Karolinska.
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Cern calling: the future of video
As sponsor of the world’s largest scientific collaborations, Cern – The European Organisation for Nuclear Research – has long been keen on technology that enables people who are geographically separated to work together.
The World Wide Web was famously invented at Cern, outside Geneva, for computer communications. And Cern has also been a pioneer of videoconferencing.
Its latest videoconferencing system is based on technology from Vidyo, a young American company. It enables hundreds of scientists across the world to take part in a single call, using a mixture of dedicated conference rooms, computers and mobile devices.
“When a physics analysis is getting close to publication, we might have 500 people taking part in a videoconference,” says Tim Smith, Cern’s collaboration and information services leader. “The video meetings are an essential part of the way we work.”
An advantage of the new system is its flexibility, incorporating older “legacy” videoconferencing facilities and new equipment.
Ofer Shapiro, Vidyo chief executive, says the Cern system may be the world’s largest private videoconferencing system. Unlike a traditional network with fixed hardware requirements, the new technology adapts to the bandwidth and video resources needed and to the resources available on the internet, as the conference is taking place. Picture quality varies but Shapiro says it is always better than using a webcam on a personal computer with no special software.