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.
- Cancerous lung tumor cells can morph into stomach cells. Tumors are known to be highly plastic, unpredictable, and do whatever it takes to survive. Scientists at Duke University, using genetically engineered mice, suggest that cancerous tumor cells in the lungs can even morph into different types of gut cells. This morphing may allow tumors to develop drug resistance, arguably the biggest challenge to the treatment of cancer. The cancerous lung cells most likely became gut cells because both cell types derive from the same parent, progenitor, cells — thus, they are developmental siblings. This specific mechanism responsible for this unexpected change is the absence of a master switch gene called NKX2-1. Mice without the NKX2-1 gene in lung tissue, actually converted lung cells into gut-like cells that even produced digestive enzymes. This morphing might be one of many ways cancerous cells can evade chemotherapy and acquire resistance. Future experiments will examine possible methods to block the plasticity of these tumor cells. Published in Developmental Cell.
- Stem cell therapy may be a potential cure for alcoholism. Mounting evidence suggests that a variety of addiction disorders can be combated with stem cell therapies. Laboratory rats, bred to drink high amounts of alcohol, significantly reduce their voluntary intake of alcohol and likelihood to relapse when given a single dose of human mesenchymal stem cells. The anti-inflammatory capabilities of the stem cells seem to be responsible for this remarkable finding. Chronic consumption of alcohol normally leads to increased inflammation throughout the peripheral nervous system and brain. The increased inflammation increases the risk of relapse which in-turn perpetuates inflammation and further relapse. By injecting stem cells intravenously or intracerebrally, rats consuming high levels of alcohol experienced reduced brain inflammation and subsequently reduced alcohol intake by 90%. These effects were seen to last for 3 to 5 weeks following a single injection. Future research will be done with other forms of addiction and human clinical studies. Published in Scientific Reports.
- Signs of vascular aging reduced in mice. The ability to grow new blood vessels is reduced as we grow older, which can result in weakness, frailty, and even chronic diseases such as heart disease, stroke, and dementia. Researchers at Harvard University recently identified a chemical compound that increases the activity of a gene that is associated with blood vessel growth and a prolonged lifespan in mice. The drug was added to the drinking water of older mice. After two months, the maximum distance the older mice ran on a treadmill increased by 56% and their blood vessel growth was comparable to that of younger mice. Future work will focus on determining the efficacy and safety of the new drug. Published in Cell.
- Reduced calorie-diet may slow ageing. Previous research in worms, flies and mice, has shown that caloric restriction reduces metabolism and extend lifespan — but research in long living animals such as primates and humans is lacking. In a new multi-centre research trial in humans called CALERIE, (Comprehensive Assessment of Long term Effects of Reducing Intake of Energy), the strongest evidence to date was obtained indicating that caloric restriction similarly slows down human metabolism. This study provides hope that caloric restriction in humans, similar to other animals, can also improve health and prolong lifespan. Published in Cell Metabolism.
- Why iron makes malaria infection worse. It is has been known that iron supplementation can worsen malaria infection — and a new study in mice provides evidence of why. Malaria parasites can consume iron as a food source. By studying mice and samples from malaria patients, researchers found that excess iron interferes with a protein (ferroportin) that prevents a toxic buildup of iron in red blood cells and helps protect these cells against malaria infection. They also found in some African populations, that a mutant form of ferroportin, can protect against malaria infection. Published in Science.