Category Archives: Research Roundup

Research Roundup: New drug effective in treating malaria, HPV vaccine pioneers recipients of Lasker award and more!

Welcome to this week’s Research Roundup. These Friday posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • A new drug, developed in animal models, is effective in treating malaria. Researchers at Tulane University have developed a new drug that is effective against non-life-threatening cases of malaria. The drug, AQ-13, cleared the parasite responsible for the disease within one week. AQ-13 was developed for use in humans only after necessarily rigorous testing in animal models, including rats and monkeys, for its pharmacokinetics (or, the way the drug moves through the body) and safety. Because current anti-malarial drugs are developing resistance, the efficacy of this new drug is especially promising. The researchers studied 66 men in Mali living with malaria, giving half AQ13 and half a standard treatment, and both groups had similar cure rates. They plan to expand their future studies to women and children before recommending it as a new widespread treatment. The research was published in The Lancet Infectious Diseases.

Anopheles funestus, a mosquito which spreads malaria in the Sudan. CDC Public health Image Library

  • UV-treated milk led to healthier outcomes than UHT milk in premature piglets. Preterm births affect 1 in every 10 infants born in the US, so improving how we care for them is hugely important. Researchers in Denmark found that preterm piglets that were fed UV-treated milk grew quicker and developed better protection against bacteria and improved gut function when compared to piglets fed with ultra-heat treated (UHT) milk. It is hoped that such knowledge can used to improve prospects for premature human babies. The scientists had previously shown that piglets born 10-days early provided a suitable model for studying immune-system development and growth in premature babies. This study was published in the Journal of Nutrition.
  • Archaic dental practice may be replaced using squid ink. Left untreated, gum disease can lead to the destruction of mouth tissue and is the leading cause of tooth loss in adults. It is currently diagnosed using a metal probe to search for gaps between the gum and tooth that indicate disease. Periodontal probing has many drawbacks besides discomfort for the patient: it may spread disease by introducing bacteria to healthy parts of the mouth, it’s time consuming, and has limited accuracy. Thankfully, a new non-invasive imaging method that was first developed using pig jaws may put an end to painful probing. A swish of squid ink in the patient’s mouth allows pressure difference in the gums to be detected by ultrasound, so the pockets caused by disease can be spotted by dentists. The ink, which is a dark liquid full of light-absorbing particles, is safe for consumption and won’t stain teeth. This research was published in the Journal of Dental Research.

  • Scientists identify why fungi spores are not more detrimental to humans, using mice. “Humans constantly inhale fungal spores. Why don’t we suffer more invasive infections from ubiquitous fungal molds such as Aspergillus fumigatus? Working in mice, Shlezinger et al. found that neutrophils phagocytosed germinating fungal spores deep in the lungs. Once engulfed, the fungal cells underwent programmed cell death, likely induced by phagocyte NADPH oxidase. Fungal strains engineered to overexpress a fungal survivin homolog resisted cell death by inhibiting caspase-3 and -7. When a Survivin antagonist was applied, more fungal cells died. These findings may lead to therapies for immunocompromised patients threatened by invasive fungal lung infections.” This research was published in the journal Science.
  • Two pioneers of the human papillomavirus (HPV vaccine) recipients of the prestigious Lasker awards. “More than 500,000 new cases of cervical cancer are diagnosed annually, and each year, more than 250,000 women die from the malignancy” — all of which are linked to certain types of HPVs. The HPV vaccine has a long history both in terms of its development and in terms of evaluation of its efficacy. It was approved in the USA in June of 2006 and “can prevent almost all cervical cancers and protect against cancers of the mouth, throat and anus. It also combats the sexually transmitted genital warts that some forms of the virus can cause.” The development and refinement of this vaccination owes much to animal research, including rabbits, cows and dogs. You can read more about the history of this vaccine at the Lasker Foundation

Research Roundup: Zika virus used to treat brain cancer, improving bladder function after spinal cord injury and more!

Welcome to this week’s Research Roundup. These Friday posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • Zika virus used to treat lethal brain cancer. Glioblastoma is a lethal brain cancer — for adults treated with current methods, the median survival time is about 14.6 months and two-year survival is 30%. In the present study, these researchers explored in mice and donated human brain tissue samples whether Zika virus (ZIKV) — a flavivirus that induces cell death and differentiation of neural precursor cells in the developing fetus — could be used as a means of killing cancer cells. They found that ZIKV preferentially infected and killed glioblastoma stem cells (GSCs) relative to differentiated tumor progeny or normal neuronal cells. Human trials are still some ways away, but this pioneering technique could someday be used in mainstream cancer research. This research was published in the Journal of Experimental Medicine.

  • New gene editing tech promises to be even better than CRISPR. A fourth-generation DNA base editor may soon become mainstream, either complementing CRISPR or replacing it. David R. Liu, a researcher from Harvard University Professor of Chemistry and Chemical Biology, states “Approximately two-thirds of known human genetic variants associated with disease are point mutations. The fourth-generation base editors to my knowledge are the most effective forms of these molecular machines that can directly correct certain types of point mutations.” While this technique is still in the extremely early stages, we expect that rigorous safety and efficacy testing, involving animal models such as mice; similar to that which has occurred and is still occurring with CRISPR Cas9. The research was published in the journal Science Advances.

Dachshund image by Becky Smith

  • Pioneering gene therapy approved for leukemia in the USA. CAR T is a pioneering type of gene therapy for cancer. CAR T cells are equivalent to given patients a “living drug”. “The therapy requires drawing blood from patients and separating out the T cells. Next, using a disarmed virus, the T cells are genetically engineered to produce receptors on their surface called chimeric antigen receptors, or CARs.” While this form of therapy has been in use in various small scale human trials, it is the first approval in the world for a type of CAR T therapy. Much of its success is due to pre-clinical safety and efficacy testing in animals models, such as mice — which we have covered previously. The “living drug”, known as Kymriah (or tisagenlecleucel), was developed by the SWISS based company Novartis, and is charging $475,000 for the life-saving treatment.
  • Malaria parasite in howler monkeys has infected humans in Brazil. There have been almost 1,000 causes of Malaria since 2006, leading scientists to try and discover the source of a disease which was once thought to be eradicated from the region. Analysis of patient DNA showed that the infections came from Plasmodium simium, a parasite that is found in howler monkeys. Zoonotic diseases, capable of transferring from animals to humans, are hard to treat, though the researchers do not believe it was transferred via a mosquito vector. One of the authors of the study noted: “However, its unique mode of transmission via monkeys and the fact that it occurs in areas of high forest coverage mean that zoonotic malaria poses a unique problem for malaria control efforts and may complicate the drive towards eventual elimination of the disease.” This research was published in The Lancet.

Research Roundup: Ecstasy to be used to treat PTSD, stem cell therapy reducing symptoms of Parkinson’s disease and more!

Welcome to this week’s Research Roundup. These Friday posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • Researchers at the University of Utah have developed a zebrafish model of opioid drug self-administration. Zebrafish were trained to swim over a yellow platform that would trigger food to be released into the tank. When the food was replaced by the opioid hydrocodone, the fish swam over the platform much more often. When the researchers reduced the dosage, the fish swam over the platform even more often to compensate. The zebrafish also continued to swim over the platform after it had been raised up – forcing the fish to fight their own dislike for shallower water. It is hoped this animal model could be used to try to develop new drugs that would block opioid-addiction or drug-seeking behavior. The research was published in Behavioral Brain Research.

  • New study suggests a relationship between higher levels of lithium in drinking water and dementia. The amount of lithium found in water varies by location. This study compared the health records of around 800,000 Danish people, with around 74,000 people having dementia. Tap water of 151 cities were then also tested. “Moderate lithium levels (between 5.1 and 10 micrograms per litre) increased the risk of dementia by 22% compared with low levels (below five micrograms per litre).However, those drinking water with the highest lithium levels (above 15 micrograms per litre) had a 17% reduction in risk. Lithium is used in the treatment of bipolar disorder, although the levels found in water are much lower. Prof Simon Lovestone, from the department of psychiatry at the University of Oxford, states, “In neurons in a dish and in mouse and fruit-fly models of Alzheimer’s disease, lithium has been shown to be protective.” This study, published in the journal JAMA Psychiatry, although correlative is intriguing nonetheless, and may highlight a useful of avenue for subsequent research.
  • Stem cell therapy proved effective in monkey model of Parkinson’s disease. Parkinson’s disease is caused by the loss of neurons that use the neurotransmitter dopamine, particularly in the basal ganglia of the brain. In order to reverse the symptoms of Parkinson’s these neurons not only have to be replaced, but also they have to survive for long periods of time, and form appropriate connections with other parts of the brain. This week, a team from Japan and Sweden showed that grafting dopamine-producing neurons derived from human induced pluripotent stem cells (iPSCs) into the brains of macaque monkeys not only achieves both of these aims, but also reverts some of the most marked symptoms of Parkinson’s, such as the tremors. The effect lasted for at least 2 years, and there was no rejection or formation of tumours- two of the main risks anticipated for such treatments. The team responsible for this research is now preparing for the next step- a human clinical trial. “We need to confirm efficacy and safety of the cells which will be used in the clinical trial. We are now doing these experiments using rats and mice”, said lead author Dr. Jun Takahashi. This study was published in the journal Nature.

  • Cancer induced anorexia inspires new anti-obesity drug studied in rats, mice, and monkeys. Anorexia and weight loss are a large part of the wasting syndrome of late-stage cancer, which further contributes to the morbidity and mortality of the cancer. This week, researchers from three major pharmaceutical companies have independently published research describing one major and responsible protein for this cancer induced anorexia or wasting syndrome; called growth differentiation factor-15 (GDF15). Specifically, they identified that GDF15 bound to a single protein receptor, whose function was previously unknown — GFRAL. They determined that GFRAL can be found in areas of the brain that are linked to appetite regulation, and then compared mice that didn’t have GFRAL receptors (knockout mice) to those that did. Following systematic injections of GDF15 in both types of mice across several weeks they found that only mice with GFRAL receptors lost weight. Another study compared weight loss in rats given GDF15 and different levels of food restriction. They found that rats without GDF15 but with food restriction lost similar amounts of weight compared to rats given GDF15 and no food restriction — thus suggesting that GDF15 suppresses appetite. Additionally, other researchers created a long-lasting version of GDF15 which allowed cynomolgus monkeys to drop 4% in body weight across 4 weeks. An exciting part of this research is that similar results are being found across multiple species. The studies on mice, rats, and monkeys were published this week in Nature Medicine.
  • New study in rats indicates walnuts may promote gut health and act as a prebiotic. Researchers at Louisiana State University studied two groups of lab rats, one that received a standard diet and one that received a diet enhanced with ground walnuts equivalent to about 2oz (1/2 cup) per day in humans. Importantly, the calorie and nutrient intake was similar between the two groups. Rats that consumed walnuts saw an increase in beneficial gut bacteria species including Lactobacillus, Roseburia, and Ruminococcaceae, as well as greater species diversity. “Walnuts are the only nut that contain a significant amount of alpha-linolenic acid, the plant-based omega-3 fatty acid (2.5 grams per one ounce) and also offer protein (4 grams per one ounce) and fiber (2 grams per one ounce),” the study authors said. These bioactive components may be a mechanism by which health benefits are conferred. The study was published in the Journal of Nutritional Biochemistry.

Image from Understanding Animal Research

  • This week, the FDA has given “green light” for ‘ecstasy’ to be tested as a therapy for post-traumatic stress disorder (PTSD). There are only two approved drugs for the treatment of PTSD, and both are considered ineffective for treatment of this disorder in war veterans. ‘Ecstasy’ has long been considered as a good candidate to treat psychological trauma due to its euphoria-inducing and fear-reducing effects. However, it was only after this psychedelic drug was deemed non-neurotoxic in rats and monkeys that FDA allowed for small-scale clinical trials. The results obtained in the last two decades indicate that ‘ecstasy’ doesn’t cause neurotoxicity in humans, in the dosages tested. This has led to FDA giving approval for large-scale phase 3 clinical trials, which will start next year, and will enroll 200-300 volunteers in 14 locations, to evaluate whether ‘ecstasy’ could be the next treatment for PTSD and, possibly, other psychiatric conditions.

Research Roundup: Possible cure for genetic infertility, zebrafish as a model organism for cancer and more!

Welcome to this week’s Research Roundup. These Friday posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • Can a new technique for the creation of artificial sperm lead to a cure for genetic infertility? Sex is determined by the X and Y chromosomes. Females have two X chromosomes (XX) and males have one X and one Y (XY). About 1 in 500 males are born with an extra Y chromosome, Klinefelter’s syndrome (XXY), while roughly 1 in 1,000 males are born with double Y chromosomes, or Jacob’s syndrome (XYY) — two different forms of trisomy, which lead to infertility. Mimicking these syndromes in mice, in a jointly funded research project by the EU and Japan, these researchers took pieces of ear tissue, cultured them and then used fibroblasts from that culture to create stem cells. Curiously, in some of these stem cells, the extra sex chromosome was lost – yielding “normal” cells. They then induced these “normal” stem cells to differentiate into sperm cells and injected them into the testes of these infertile mice where the matured into healthy sperm cells — although some of these mice developed tumors. These healthy sperm cells were then collected and through assisted reproduction, created healthy fertile offspring. In a preliminary experiment, they also found that stem cells derived from men with Klinefelter’s syndrome also lost their extra sex chromosome. This research was published in the journal Science.

Image: Research schematic. Credit: Takayuki Hirota.

  • Adult neurogenesis found in the brain area that links memory to emotion. Neurogenesis (the formation of new neurons by cell division, and their incorporation to existing circuits) is a powerful mechanism of brain plasticity. Previous studies have indicated that neurogenesis only occurs in a few parts of the adult brain. This week, a team from the University of Queensland has reported that neurogenesis also occurs in the adult mouse amygdala, a structure located deep in the temporal lobe which is linked to the establishment of emotional memories. The amygdala plays a key role in controlling the way people react to certain stimuli or an emotional event, particularly if these are viewed as potentially threatening or dangerous. “Finding ways of stimulating the production of new brain cells in the amygdala could give us new avenues for treating disorders of fear processing, which include anxiety, PTSD and depression”, said author Dr. Dhanisha Jhaveri. This study was published in the journal Molecular Psychiatry.
  • Plausibility of humanized mice questioned for stem cell transplant research. Humanized mice are engineered to have human immune systems, rather than a typical mouse immune system, and are frequently used across research. Some studies using humanized mice investigate the immune response to transplanting pancreatic islet cells for diabetes or skin grafts for burn victims. Recently, however, researchers at Stanford are suggesting that these mice are unsuitable for investigating questions related to stem cell transplantation and immune function/response. Their suggestion comes from several experiments where they transplanted genetically mismatched human stem cells in either humanized mice or actual humans. They found that humanized mice often accepted these transplants, while humans often rejected these transplants. Therefore, humanized mice might not be the best animal model for understanding relationships between stem cell transplantation and immune response. This is a great example of scientists working together to assure that animals’ lives are not wasted and the ability of science to refine its methodology over time. This study was published in Cell Reports.
knockout mice, animal research, animal rights

Researchers found that humanized mice often accepted stem cell transplants, while humans often rejected these transplants. (Mouse image from NIH)

  • Artificial womb used to successfully grow premature lamb for the second time. A collaborative of researchers from the Women and Infants Research Foundation, the University of Western Australia, and Tohoku University Hospital, Japan have successfully brought a preterm lamb to full term in an artificial womb. This study is similar to the results reported earlier this year by researchers at the Children’s Hospital of Philadelphia. Here, the lamb, analogous to a human fetus aged around 23 weeks old, was placed into a clear plastic bag filled with special amniotic fluid and an artificial placenta. Associate Professor Matt Kemp, led the development of this second artificial womb says,. “By providing an alternative means of gas exchange for the fetus, we hoped to spare the extremely preterm cardiopulmonary system from ventilation-derived injury, and save the lives of those babies whose lungs are too immature to breathe properly.” This advancement provides hope for families of babies who are born extremely premature in the possibility of increased survival rates.This study was published in The American Journal of Obstetrics and Gynecology.

  • Zebrafish larvae might be used to help doctors decide the best course of treatment for each cancer patient. A group of researchers from the Champalimaud Centre for the Unknown published this week, in the journal PNAS, preliminary data showing that colorectal cancer cells taken from patients can be injected in zebrafish larvae where they develop and show all the hallmarks of tumors. The researchers then treated these zebrafish avatars with different chemotherapy cocktails. In 4 out of 5 tested samples, the tumors grown in zebrafish responded similarly to how donor patients had responded to the chemotherapy they had gone through. This proof-of-concept study shows that there is promise in using zebrafish to predict, in just 2 to 3 days, how a patient will respond to each available treatment, and guide its chemotherapy regime accordingly. This study is now in a 2nd phase that includes hundreds of patients from the Champalimaud Centre for the Unknown and the Amadora-Sintra Hospital.

Research Roundup: GM Pigs and hope for the organ crisis, tiny robots helping to cure bacterial infections and more!

Welcome to this week’s Research Roundup. These Friday posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • Progress to end the organ donor crisis being made thanks to GM pigs. We have previously written about the use of genetically modified pigs and their valuable role in attenuating the organ crisis here. Since then, it was discovered that latent viruses in pig tissue, could infect humans – making organ transplants even more difficult. In the present study, researchers using CRISPR were able to delete 25 porcine endogenous retroviruses (Pervs), hidden in the pig’s genetic code, and using cloning technology, were able to place virus free genetic material into a pig’s egg and create embryos. While still an inefficient process, this proof of principle study led to birth of 37 healthy piglets and hope for an end to the organ crisis. This research was published in the journal Science.

  • Why does Queen Bee’s Royal Jelly heal wounds? For many centuries, honey-bees have been regarded as one of nature’s pharmaceutical companies because of the natural health benefits — antibacterial, anti-inflammatory, and immunomodulation — of honey, bee pollen, and royal jelly. Unfortunately, because bees are not highly regulated like pharmaceutical companies, their byproducts may contain pollen that causes a range allergic reactions in humans; for example, ragweed pollen. In efforts to take advantage of the healing properties of royal jelly, and remove the unknown side-effects, researchers from Italy and Slovakia set out to identify why royal jelly can heal wounds. They first isolated various molecules in the royal jelly and tested it on in vitro cell cultures for wound healing after mechanically scratching the cells. From these tests the scientists were able to identify defensin-1 as a possible wound-healing peptide. To determine the wound healing properties of defensin-1 they treated experimentally identical wounds on rats with either defensin-1, royal jelly, or cellulose-based gel (control). Through these experiments, they demonstrated that defensin-1 facilitated healing as much as the royal jelly in comparison to the control — which did little to facilitate healing. This research opens the possibility of a new healing agent from honey-bee byproducts that is free of the potential side-effects of allergens. This study was published in Scientific Reports.

  • Cardiac stem cells from young hearts could rejuvenate old hearts“Cardiac stem cells from young hearts could rejuvenate old hearts: Animal study reveals that cardiosphere-derived cells secrete tiny vesicles that could ‘turn back the clock’ for age-related heart conditions,” says a statement from Cedar Sinai Medical Center. Dr. Eduardo Marbán’s research team injected a specific type of stem cell from newborn research rats into aged rats. Their findings in the recipients showed improved heart function, longer heart cell telomeres (which usually shrink with age), increased exercise capacity and faster hair growth. More study is needed to fully understand the applications for treatment of human disease. Dr. Lilian Grigorian-Shamagian, co-primary investigator and the first author of the study, indicates that they want to determine whether this therapy will result in longer life spans and if the stem cells must come from a young donor to have the rejuvenating effects. This study was published in the European Heart Journal.
  • Tiny robots used to cure stomach bacterial infections in mice. Current treatment of bacterial infections of the stomach, such as ulcers, leads to nasty side effects because of the use of proton pump inhibitors.These inhibitors are needed to suppress the production of gastric acid in the stomach which otherwise would destroy antibiotics before they had an opportunity to work. In a proof of principle experiment these researchers used a vehicle with a spherical magnesium core to deliver antibiotics. By exploiting the chemical reaction of magnesium and gastric acid these researchers were able to successfully dose mice daily with antibiotics across 5 days. Because the by-product of magnesium interacting with gastric acid is the production of hydrogen bubbles – the vehicle naturally moves through the stomach. The vehicle itself is sensitive to surrounding acidity and only releases antibiotics once acidity is lowered. Moreover, the vehicle itself is made of biodegradable materials – causing no harmful effects. This research was published in Nature Communications.

Schematic displaying the loading of antibiotic unto magnesium based micro-motors.

  • A study in Siberian hamsters suggests that exposing parents to dim night light can lead to depressive-like behaviors in their offspring. There is an established link between light levels at night and depressive behaviour, but this study looks at the impact on the next generation. Now, researchers at Ohio State University Wexner Medical Center exposed Siberian hamsters to low level night lighting (five lux – less than would come off a mobile phone) nine weeks before mating. They found changes in the neuroendocrine system of the offspring higher levels of depressive-like behaviour when those animals became adults. This study was published in Psychoneuroendocrinology.
Exposure to dim light at night increases depressive-like behaviors in offspring

Photo credit: Phillip Roberts

Research Roundup: Combatting Zika virus, Understanding the brain, reprogramming skin cells, and more

Welcome to this week’s Research Roundup. These Friday posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • A new model to study the transmission of Zika virus. Scientists at the National Institutes of Health (NIH) have developed a mouse model to study the transmission of Zika from males to females, as well as from females to their fetuses. Scientists from the National Institute of Allergy and Infectious Diseases (NIAID) devised a way to make the typically-difficult mouse model be a reliable Zika model. Mice naturally defend against Zika better than people because they have a stronger interferon response. The scientists discovered a way to suppress the interferon in these mice, called anti-interferon Rag (AIR) mice, which have prolonged virus infection in the testes — similar to Zika-infected men. AIR mice also exhibited vertical transmission of Zika from mother to fetus. Intriguingly, only some fetuses from each female were infected with Zika, suggesting that the placenta may be a crucial barrier in preventing the virus from reaching the fetus and thereby resulting in birth defects. The research was published in Scientific Reports and is freely available online.
  • Scientists at Ohio State University have used mice develop a new way to reprogram skin cells. This could represent a breakthrough in repairing injured or ageing tissue. The new technique, called tissue nanotransfection, is based on a tiny device that sits on the surface of the skin of a living body. An intense, focused electric field is applied, allowing it to deliver genes to the skin cells beneath it – turning them into different types of cells. The device was put on the skin of the mice with legs that had had their arteries cut, preventing blood flow through the limb. The team found that they were able to convert skin cells directly into vascular cells -with the effect extending deeper into the limb, in effect building a new network of blood vessels. “Seven days later we saw new vessels and 14 days later we saw [blood flow] through the whole leg,” said Dr. Chandan Sen, from the Ohio State University. Sen and colleagues say they are are hoping to develop the technique further, with plans to start clinical trials in humans next year. This research was published in Nature Nanotechnology.

  • Neuroscientists are trying to under how tangles of neurons produce complex behaviors. The brain is still largely unknown. Researchers hope to map out simple brains in hopes to see patterns that might be able to be applied to more complex brains.  Researchers at Howard Hughes Janelia Research Campus are studying the brains of fruit fly larvae. The brains of these animals are comprised of 15,000 neurons as compared to 86 billion in the human brain.  Researchers like Albert Cardona and Marta Zlatic‘s feel that a wiring diagram is an important step towards understanding how the central nervous system works.  The nematode’s (C. elegans) brain, at just 300 neurons, was mapped in the 1980’s but scientists question its applicability to larger brains so have sought the fruit fly because it exhibits more complex behaviors and thus more complex neural pathways and actions but there is still much unknown about simple brains. Animals being looked at include the gastric system of crabs, larval zebrafish and specific regions of the brain. Neuroscientists hope that mapping the brain will help to understand why some therapies work for one but not for others and how new therapies can be developed to treat many debilitating diseases.

  • Scientists destroy entire chromosome with CRISPR providing hope for future generations of individuals with aneuploidy, such as Down Syndrome –where an individual has an abnormal number of chromosomes. These researchers first, in vitro, used CRISPR-Cas 9 to induce numerous chromosomal breaks at the centromere on the long arm of the Y chromosome, effectively removing the chromosome from XY embryonic stem cells. Then, using male mice zygotes, in vivo, this team of researchers targeted 41 sites of the Y chromosome centromere, resulting in a 70% efficient removal of the Y chromosome. This research was published in the journal Molecular Therapy.
  • Gold particles increases the efficacy of drug treatments for cancer. Gold can be used as a catalyst in chemical reactions. Researchers from Edinburgh University, using zebrafish investigated whether gold would improve the efficacy of drugs, via catalysis, used to treat lung cancer. Here, gold nanoparticles were encased in a “chemical device”, and the activation of the structure as well as the subsequent release of therapeutics studied — which worked with good efficiency. The lead author, Dr. Unciti-Broceta states “We have discovered new properties of gold that were previously unknown and our findings suggest that the metal could be used to release drugs inside tumours very safely.” This research was published in the journal Angewandte Chemie (Applied Chemistry).

Research Roundup: Chimpanzees with Alzheimer’s, mice with autism, the shrinking bat genome and more

Welcome to this week’s Research Roundup. These Friday posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • Signs of Alzheimer’s found in chimpanzees for the first time.  Melissa Edler, of Northeast Ohio Medical University, and her colleagues, studied twenty brains of older chimpanzees and found more than 50% had beta-amyloid plaques and early forms of tau tangles similar to that seen  in humans with Alzheimers.  Another researcher, Mary Ann Raghanti of Kent State University, Ohio, whose lab in which the work was conducted, points out that the samples were not accompanied with cognitive data and there are no current examples of chimps with Alzheimers-like dementia.  This may show that although chimps demonstrate physiological aspects of the disease, they do not exhibit the cognitive decline as seen in humans. Raghanti says, “If we can identify those differences between the human and chimp brain then we might be able to pinpoint what is mediating the degeneration. That could be a target for drug treatment.”
CC-BY-NC-SA

Chimpanzees at NCCC (not related to above study). Photo credit: Kathy West.

  • Human embryos edited to stop diseases using CRISPR. In a massive collaborative effort, researchers in the USA and Korea, have for the first time “freed embryos of a piece of faulty DNA that causes deadly heart disease to run in families.” Hypertrophic cardiomyopathy, is a common heart disorder, affecting approximately one in every 500 people, and can lead to cardiac arrest. In this study, “sperm from a man with hypertrophic cardiomyopathy was injected into healthy donated eggs alongside Crispr technology to correct the defect” — and in 72% of the embryos the disease-causing mutation was removed. Safety and efficacy evaluation of the CRISPR technique is still under scrutiny, and this evaluation owes much to animal research as we have previously highlighted in our research roundups. This research was published in the journal Nature.

  • ‘Autistic’ mice affect the behaviour of their littermates. Researchers at Cardiff University, led by Dr Stéphane Baudouin, genetically altered mice to exhibit symptoms of autistic spectrum disorder and found that other unaltered mice became less social. The mice altered mice had the neurolignin-3 gene turned off, changing their behaviour. Wild-type mice in the same cage ceased to be interested in the smells of the urine of other mice – a standard test for social behaviour in mice. When the Neurolignin-3 gene was turned back on, both the altered mice and the wild-type in the cage returned to their ordinary behaviours. Dr Badouin also found that the ‘autistic’ tendencies of the mice were worse when the mice where housed with wild-type mice compared with housed with other altered mice. This study was published in eNeuro.
  • Genome elasticity and shrinking found in bats. The size of genomes are known to vary across the animal kingdom: hummingbird — 1.11 billion base pairs (bp); human — 3.42 bill. bp; leaf insect — 7.82 bill. bp. These sizes are typically maintained across millions of years, but when they do change it is usually an increase in size from the addition of transposons. Transposons are classically referred to as “jumping genes” and partly drive genetic evolution. Researchers at the University of Utah recently studied size change of genomes and transposons in the common little brown bat (Myotis lucifugus) and found something interesting. Around 40 – 50 million years ago, the genome had gained 400 million transposons and shrunk in size — over a small amount of time (in evolutionary terms) the genome dramatically changed. Because genomes serve as the raw materials to living life, this is a huge finding. Furthermore, mammalian genomes are widely recognized as monotonous — rarely changing in size over time and rarely gaining many transposons, however it now appears the little brown bat is an anomaly. Further research on these bats and other mammals will help us better understand the relationship between genes and evolution.
  • A less invasive form of swabbing is being investigated as a means of refinement aiming to improve the welfare of zebrafish. Zebrafish use continues to increase, because of their utility as a model organism for investigating both basic and applied biological mechanisms related to health and disease. Previously, the collection of DNA from zebrafish was done via fin clipping — a fairly invasive procedure performed without anesthesia. With funding from the NC3Rs, researchers at the University of Leicester’s Department of Neuroscience, Psychology and Behaviour are systematically exploring a new technique. Here, “researchers gently stroke a swab along the flank of a netted fish and takes just a few seconds to complete. Previous research by this team has already shown that this technique collects ample material for DNA analysis.” This two year project will investigate the potential benefit to the animals’ wellbeing by comparing the standard method to the newly proposed one.