By Nadia Jones (see more of her blogs at online college)

For several months, animal rights activities in the UK have been putting extreme pressure on companies involved in the transport of animals intended for scientific testing, to the extent that in January, according to BBC News, the last major ferry operator willing to transport animals capitulated, and will no longer participate in the shipment of animal research specimens.

Most of the animals used in British laboratory experiments are raised on the island — only 1% of the animals are imported — but scientists say that the unofficial embargo on research animals threatens to undermine bio-medical research, and may ultimately have severe consequences for human patients.

Furthermore, without access to the specific animal strains they need, which are often imported from specialist breeding facilities around the world, it’s not just the research that will be significantly impacted.

BBC News reported that, “the life sciences sector generates some £50 billion a year and employs more than 165,000 highly skilled workers.  But that won’t last if researchers can’t get the animal models they need to study disease and develop new drugs.”

Unfortunately, this is not a new story.  The recent campaign against transportation companies is just one of many efforts by animal rights activists over the past century to put an end to animal testing.

Though there are several arguments leveraged against animal testing, the primary thrust of most activists’ cases is that animal testing is unethical and cruel.  A report by the British Royal Society also notes that “opponents of the use of animals in research frequently use the availability of alternative, non-animal, research methods as evidence that using animals is unnecessary.”

Researchers and scientists, however, have a strong counterargument.

US researchers, for instances, recently made the case at an annual meeting of the American Association for the Advancement of Science that, “not doing animal research would be unethical and cost human lives,” further saying that testing on animals has led to “dramatic developments in research that have improved and affected the quality of human life.”

Similarly, Science Minister David Willetts in the UK told BBC News that “the use of animals in research remains essential to develop new treatments and drugs, improve our understanding of disease and prove the safety and effectiveness of drugs and chemicals before they go forward for human trials.”

The Royal Society, in the report The use of non-human animal in research: a guide for scientists, claims “almost every form of conventional medical treatment, such as drugs, vaccines, radiation, or surgery, rests in part on the study of animals.”

And there are numerous cases that support their claim: in the early 1950’s and 60’s polio vaccines were introduced to the world, virtually eliminating the disease, developed with animal testing; in the late 1970’s, immunosuppressive drugs, which make kidney and other organ transplants possible and effective, were developed using animal testing; testing on animals continues to provide new insights into the CFTR activators that play such a large part in cystic fibrosis, bringing us ever closer to new treatment and therapy solutions.

Animal testing works because non-human animal biological systems act as models for human systems and allow scientists to determine a compound’s “safety and efficacy, whether a compound is safe for human ingestion and also whether or not a product works for its intended purpose,” according to Frankie Trull, president of the non-profit Foundation for Biomedical Research.

Trull went on to explain that while animals are not perfect analogs of human biology, “they’re still as close as we’re going to get without using a human.”  Scientists hope one day to rely fully on computer modeling and other non-animal models, but that realizing that hope is still far away, and until we reach that level of sophistication, animal testing is a resource that has the potential to solve many human problems.

Author Bio:

This is a guest post by Nadia Jones who blogs at online college about education, college, student, teacher, money saving, movie related topics. You can reach her at nadia.jones5 @ gmail.com.

 

Posted by: thearkhive | March 28, 2012

Speaking out on animal research

An excellent post published yesterday by Fiona Fox, Director of the Science Media Centre, focusing on the recent news that over the past 7 years UK airlines and all ferry companies have withdrawn from carrying animals for scientific research after a campaign by animal rights activists.

A must read! – See it here.

Posted by: thearkhive | February 3, 2012

Mice solve cancer blood supply mystery

All cells require oxygen to survive, and this axiom also holds true for cancer cells. Without a constant blood supply which delivers red blood cells rich in oxygen, cells will die. Tumours are uniquely adept at developing their own blood supplies, a process called neovascularisation, in order to maintain growth (see here for more on neovascularisation).

But could this fact be cancers Achilles’ heel? If treatments could block neovascularisation then it would be possible to effectively starve cancer cells. Many new drugs aim to do just that and many of them have completely failed in when given to patients, especially if they suffered from breast cancer.

Why this is the case has flummoxed researchers for years. Despite the loss of a blood supply tumours just kept on growing. Starving cancer didn’t work.

However, recent work published in PNAS (see it here) has thrown light onto this problem. To mimic human cancer, scientists implanted human cancer cells under the skin of mice. These cells happily live in this environment and as they multiply they require more oxygen to survive. So, just like in humans, these cells release various chemicals that initiate neovascularisation, highjacking and stimulating mouse cells to develop a new blood supply required by the growing tumour.

Mouse models like these are the bread and butter of cancer research and have for years been integral for drug development.

But what the researchers did next was of significant importance.

These cancer-bearing mice were given treatments designed to block neovascularisation. Not surprisingly they reported a loss of blood supply and a reduction of oxygen content (known as hypoxia) to the tumour.

But what they also observed was an increase in the number of cancer stem cells within those tumours: low oxygen conditions had created more cancer stem cells helping the tumour survive. Cancer stem cells are thought to be vital for the continued growth of many tumours, and any process that increases their number should not be encouraged.

Therefore, it seems that drugs that block neovascularisation inadvertently increase cancer stem cell populations and might actually help tumour development.

These mouse models have elegantly shown us that new treatments should target cancer stem cells as well as trying to block the tumours new blood supply.

Posted by: thearkhive | December 17, 2011

Cuts to US Chimpanzee Research.

Good news this week as the US Institute of Medicine (IOM) released a report stating that most uses of chimpanzees in medical research are unnecessary. They recommended a significant reduction in any government funding that supported chimpanzee studies with the aim of curtailing research on our animal cousins. In a further positive move, the National Institute of Health (NIH) has taken on board these recommendations and will implement them as soon as possible.

See the full story in Nature here

Posted by: thearkhive | October 30, 2011

An Unwelcome Inheritance

Our genes, given to us by our parents, make up how we look and influence who we are. We are like our mothers and fathers, grandmothers and grandfathers, because our genetic code is a composite of theirs. So, we can thank grandma Doris and granddad Alfred for their genes which help keep our trillions of cells alive and happy.

But sometimes we don’t get the genes we want. For example, some cancers, known as hereditary cancers, run in families and as long as these defective genes do not limit a person’s ability to reproduce, they slowly spread throughout the population.

Take BRCA1 (Breast Cancer 1), a gene that produces the breast cancer type 1 susceptibility protein responsible for repairing DNA. Found in breast tissue, mutations in BRCA1 means that damaged DNA cannot be fixed properly leading to uncontrolled cell growth.

Hundreds of mutations of BRCA1 have been identified and women harbouring a mutation are 60% more likely to develop breast cancer. Therefore, furthering our understanding of this gene and the protein it encodes for is vital in order to help women with this hereditary killer.

So, it is good news that scientists, using various genetically modified mice, are investigating exactly how the BRCA1 protein works. In an article reported this week in the prestigious journal Science (see it here), researchers manipulated mouse DNA to create animals that had specific mutations in the BRCA1 gene. This mimics the human situation, providing relevant models to examine exactly how the BRCA1 protein works.

Now, the BRCA1 protein is composed of several active sites. It was uncertain which specific sites were directly involved in the suppression of cancer. By creating mice that had mutations in certain sections of their BRCA1 proteins they were able to identify the active sites required for breast cancer suppression.

Without getting too bogged down in the details, these studies elegantly show how the BRCA1 protein works and where the mutations occur that lead to hereditary breast cancer. Consequently, this work and these mouse models lead to a greater understanding of BRCA1 mutations and should result in improved diagnosis and treatments for this malignancy.

Posted by: thearkhive | September 27, 2011

Will guppies dominate the world?

The Ark Hive usually focuses its attention on animals in biological and medical research. However, today we will look at a different area of research, ecology, where in order to understand animals in nature scientist must closely examine their habitats and behavioural traits.

These things are extremely important to understand, especially when trying to comprehend how invasive species dominate over a local population and endanger biological diversity.

Fish seem to be particularly susceptible to invasion, a recent study suggesting that 68% of 20th century fish extinctions in North America are associated with introduced species. It is thought that continued introductions of exotic species will continue to pose a serious threat to natural communities.

Therefore, it is with some interest to see a study, published in PLoS One (see here), investigating the impact of the Trinidadian guppy, one of the most popular freshwater aquarium fish species in the world. These guppies are very aggressive invaders and once they take hold within an ecosystem they impact negatively upon local freshwater species.

But how are these guppies able to out muscle and out breed other fish species? Well, these fish are characterised by a mode of reproduction in which embryos develop inside eggs that are retained within the mother’s body (termed ovoviviparity). They can also store sperm meaning that a single female can give birth to many broods of living offspring. As guppies usually occur in isolated habitats where females have limited opportunities of encountering a mating partner, sperm storage, combined with live birth, provided an evolutionary advantage providing invasive success.

Amazingly, there has even been a report of a case demonstrating that a single guppy successfully founding a population within hostile waters.

However, lets get back to the research. Scientists set-up 30 experimental water enclosures (termed mesocosms) housing a variety of fish species. They then introduced a female Trinidadian guppy and waited to see whether a guppy population would dominate over the native species. The experiment lasted two years, by the end of which 86% of the mesocosms were ‘controlled’ by guppies.

These results have significant implications for local freshwater species. The introduction of a single animal can dramatically alter delicate ecosystem balances and these findings reinforce the need for caution when releasing exotic species into the wild.

Posted by: thearkhive | September 5, 2011

Diabetic Drugs without the Downside

Every week we read stories about how we are all getting fatter. We eat more, exercise less, and expect science to solve the problem of our ever growing waistlines. Along with obesity comes diabetes mellitus type 2, a metabolic disorder characterized by high blood sugar caused by insulin resistance and relative insulin deficiency.Pharmaceutical companies, who readily financially exploit human weaknesses, are desperately trying to find the side-effect free, weight loss, antidiabetic panacea.

Therefore, most will be intrigued to read this week’s Nature (see here) reporting on new drugs with unique modes of action to treat diabetes type 2. Normally, patients with diabetes are given thiazolidinediones (TZD), drugs designed to activate PPARγ, an important receptor in obesity-linked diabetes. However, many experience significant side effects, including fluid retention, weight gain, congestive heart failure and weakening bone structure.

These problems are caused by the way TZDs bind to PPARγ. It seems that TZDs activates PPARγ and also blocks the obesity-linked activation of PPARγ by cyclin-dependent kinase 5 (Cdk5). Researchers have found that it is this direct activation, not the Cdk5-dependent activation, which causes TZDs side-effects. So, the drug is not working in the best way and could therefore be improved, i.e. by creating a drug that can block the Cdk5-dependent activation of PPARγ without directly activating PPARγ on its own.

And this is exactly what these new reported drugs do. Known as SR1664 and SR1824 researchers demonstrated that these compounds do not activate PPARγ, but still bind the receptor and block Cdk5 activation of PPARγ. These results were confirmed in mice eating high glucose diets where one compound, SR1664, had potent antidiabetic activity without causing fluid retention or weight gain, serious side effects of many of the PPARγ drugs.

Hopefully this work will lay the foundations for more new drugs to treat the ever growing health problems associated with poor diet and exercise regimes.

Posted by: thearkhive | August 26, 2011

Bacteria Beat Breakbone Fever

The little mosquito has been a bane on humanity for centuries (and the Ark Hive has moaned about them before – see here). Probing, blood thirsty insects whose probosci find human skin easily penetrable. Millions of them move rapidly about, spreading diseases as they go. Normally only a concern among tropical nations, global warming finds them heading northwards, to inflict their viruses upon populations with limited genetic resistance.

One particularly horrible ailment borne by mosquitoes is Dengue fever, chillingly also called breakbone fever, a tropical disease caused by the Dengue virus. Symptoms are similar to measles, although there is an unfortunate propensity for the illness to cause internal bleeding, low blood platelet counts, and blood plasma leakage, leading to shock and life-threatening Dengue fever haemorrhage. Not a nice way to go.

Shockingly, approximately 50 million cases of Dengue fever are diagnosed annually and it is endemic in over 100 countries. As the world warms this figure is likely to climb leading to significant public health problems. Consequently, new anti-viral treatments are desperately needed to tackle the spread of the disease.

Nature this week (find it here) reports on an interesting approach which may limit the spread of Dengue fever. Infecting the principal mosquito vector (the mosquito strain that harbours the virus), Aedes aegypti, with the bacterium Wolbachia pipientis, researchers discovered that these bacteria stopped the virus replicating inside the mosquito. Annoyingly, the infection also reduced the mosquitos’ reproduction rate by 56%, meaning that if released into the wild they could not dominant over the uninfected mosquito strains; therefore Dengue fever would still be rampant.

However, the article further reports that by infecting with a slightly different Wolbachia pipientis, termed Wolbachia wMel, it was possible to limit the spread of Dengue fever virus whilst not affecting mosquito reproduction. Mathematical modelling predicted that if the Wolbachia wMel infected mosquito was released into the wild it could take hold within the normal population within a few generations, potentially reducing Dengue fever significantly.

A wonderfully novel approach to a dangerous disease, this type of research has massive potential and could help save millions of lives in the near future.

Posted by: thearkhive | July 27, 2011

The Ark Hive wins blog award

The Ark Hive has won a blog award from Understanding Animal Research (see here)

Dr. Paul Foster, a Lecturer in Molecular Endocrinology at the University of Birmingham, is an experienced cancer researcher and pharmacologist with a strong interest in understanding how animals help advance medical research.

We really like his blog – The Ark Hive – which has an eclectic mix of subjects united by clarity of coverage. Subjects range from lengthening life-spans (of nematodes) to the West Nile virus.

For material like this:

‘We’d all like to live longer. In fact some people believe, famously the gerontologist Aubrey de Grey from Cambridge University, that the first person to live a thousand years has already been born. But, despite these claims, at present, our understanding of the aging process remains in its infancy.’

we are very happy to award Paul with the status of being this Wednesday’s winner.

Posted by: thearkhive | July 19, 2011

Nematode Protein Lengthens Lifespan

We’d all like to live longer. In fact some people believe, famously the gerontologist Aubrey de Grey from Cambridge University, that the first person to live a thousand years has already been born. But, despite these claims, at present, our understanding of the aging process remains in its infancy.

The Ark Hive has previously blogged on scientists’ attempts to elongate the life-spans of nematode worms (see here and here). These studies aim to understand the fundamental molecular processes and alterations that occur as cells mature. Nematode worms provide an excellent model as their life-spans are extremely predictable (at 14-21 days) and they can be rapidly bred. Furthermore, scientists are also able to manipulate their molecular processes, allowing them to block specific pathways and understand how these changes influence aging.

A recent study in PLoS Biology (find it here) utilises interference RNA technology (iRNA) to alter how nematode worms age. iRNA blocks specific proteins from being transcribed from DNA and therefore can be used to inhibit certain cellular processes. Researchers blocked a range of proteins in the worms and highlighted the importance of 17 protein candidates that could increase lifespan.

When these proteins were interfered with in worms that had mitochondrial perturbations – a known mechanism shown to elongate life – the loss of one protein, ceh-23, shortened lifespan. Indeed, when researchers artificially engineered the worms to over-express ceh-23, the worms lived significantly longer and this effect was related to this proteins localisation in the nucleus of neuron and intestinal cells.

Therefore, ceh-23 seems to be activated by mitochondrial perturbations, localises to the cell nucleus, and there influences DNA.  By this mechanism the organism’s life is increased. This newly identified molecular pathway should enable a greater understanding of the aging process and age-dependent diseases in animals, and may give a better insight into how we could extend human longevity.

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