Research Roundup: The link between inflammation, obesity and the inability to taste, the connection between anxiety and Alzheimer’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.

  • A wide range of drugs interfere with the gut microbiome. Gut microbes are essential for human health, and interact with any substances digested by the human body. After screening 1,000 non-antibiotic drugs, scientists determined that around 25% of these drugs restricted the growth of at least one type of gut bacteria and nearly 5% affected at least ten types gut bacteria. Restricting the growth of gut microbes may modulate drug efficacy and toxicity. The types of drugs tested include anti-inflammatories, antipsychotics, and cancer drugs. Gut bacteria was obtained from fecal samples of healthy humans and tested in a dish. Before any translational application can be pursued, these findings will need to be replicated in animal models, such as mice. Published in Nature.
  • Inflammation from obesity dulls taste buds. It is well document that an individual’s sense of taste dulls as they gain weight — but we don’t know why. Research on the taste buds of mice fed a specialized fatty diet suggests that inflammation because of obesity is at least part of the cause. First, scientists fed either a high fat diet or normal diet to mice and compared tongues. The mice with a high-fat diet became obese and lost 25% of their taste buds. They then fed the same diet to genetically engineered obese-resistant mice and found no loss of taste buds, thus being obese was linked to the dulling of taste, not the diet itself. Because obesity is linked to low-grade systemic inflammation, they then fed the high-fat diet to mutant mice with and without TNF alpha — a compound that leads to inflammation in the body and that is higher in obese humans and mice. Those without TNF alpha, became obese but showed no loss in taste buds, while those with TNF alpha became obese and showed a loss in taste buds. Thus, low-grade systemic inflammation, from obesity, is associated with a dulling of taste buds. Also, TNF alpha may be used as a new target for therapies to restore taste in obese humans, which may help obese individuals adhere to new diets. Published in PLOS Biology

  • Nanofiber dressings inspired from human fetuses promote wound healing. Wounds of human and other mammalian fetuses normally heal without scarring, and many scientists are actively attempting to replicate the qualities of fetal skin to develop technologies for scarless wound healing in adult humans. A new nanofiber dressing has been developed from these studies and was tested in a mouse model. The new dressing promoted 84% tissue restoration in 20 days, compared to 55.6% tissue restoration from standard dressings. Additionally the new bandage healed wounds to have normal thick and healthy skin with hair growth, indicating minimal scarring. Understanding the mechanisms behind this new nanofiber dressing and how it may be used for treatments, is an exciting advancement in the field of regenerative medicine. Published in Biomaterials.
  • Chickens and Mice Help Scientists Understand Why Babies Kick in the Womb. A team of researchers from Trinity College and the Indian Institute of Technology worked with chicken and mouse embryos to understand the significance of movement in the womb. They learned that fetal “kicking” signals proper development of both bones and joints. Lead researcher, Dr. Paula Murphy, says, “The relative lack of understanding around how cartilage was directed presented an unfortunate knowledge gap because there are many painful debilitating diseases that affect joints — like osteoarthritis.” The discovery of how cells are signaled to make cartridge offers the opportunity to explore ways to develop better treatments for people with joint injury and disease. Published in Development.
Mouse embryo. Source.
  • Anxiety, Blood Vessels, Alzheimer’s disease and Mice. Researchers have demonstrated for the first time a connection between anxiety and problems with blood vessels with Alzheimer’s disease in mice. Lead author, Dr. Francesc Jiménez-Altayó, says, “Vascular disease…. is an emerging concept in the study of Alzheimer’s disease which is gaining clinical interest, given that subsequent cardiovascular insufficiency can alter the blood flow distribution to different organs and tissues, including the brain, which can worsen a pathology related to this type of dementia.” The changes in vasculature were more pronounced in female mice. More research is needed, but the discovery offers an explanation for abnormalities in organ and tissue function and its relation to progression of anxiety behaviors due to the abnormalities in peripheral blood flow. Published in the Journal of Alzheimer’s Disease.