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.
- An artificial womb has successfully kept premature lambs alive. Extreme prematurity — infants born at 22 to 23 weeks gestation — is a leading cause of infant mortality, and infants who do survive often have serious disabilities like cerebral palsy or major cognitive deficits. Researchers at the Children’s Hospital of Pennsylvania have developed a first-of-its kind artificial womb that mimics the uterine environment, and have found in studies of lambs that this womb allows the premature lambs to grow normally inside the womb for 3-4 weeks. The thought is that treating the preemies more like fetuses than newborns by extending normal gestation may give them a better chance of survival. The artificial womb, pictured below, is a fluid-filled transparent container that simulates how fetuses float in amniotic fluid inside the mother’s uterus. The womb is attached to a mechanical placenta that keeps blood oxygenated for the fetus. Over the four weeks of study, the lamb fetuses grew to open their eyes, grow wool, breathe, and swim. Human trials are still several years away, though the research team is already in discussions with the Food and Drug Administration. The study was published in Nature Communications and is freely available for download.
- New research finds that at least one third of all gut nerve cells are replaced weekly. The gut contains the second largest nervous system in the body, the enteric nervous system. Similarly to the number of viable eggs that a woman is born with, it was a once held scientific belief that the gut nerve cells we’re born with are the same ones that we die with. Using healthy adult you mice, and a variety of modern techniques, this study confirmed previous research findings of ongoing neuronal cell loss because of apoptosis (cell death) — although total neuronal numbers remain constant. This observed neuronal homeostasis was found to be maintained from dividing precursor cells that are located within myenteric ganglia. Mutation of these adult precursors led to an increase in enteric neuronal number, resulting in ganglioneuromatosis, modeling the corresponding disorder in humans. Since gut nerve cells were thought to remain unchanged across time, it has limited our understanding and treatment of diseases which affect the gut. These results “enable a new understanding of the pathogenesis of enteric neuromuscular diseases as well as the development of novel regenerative therapies.” This study was published in the Proceedings of the National Academy of Sciences.
- A new study finds that protein found in human blood makes mice smarter. Previous research investigating the effects of young blood on aging animals has generally focused on within (same) species comparisons. In this study, researchers investigated the role of a human umbilical cord plasma and its effects on aged mice — in particular with respect to hippocampus and behavioral measures of cognition. These particular measures were investigated as impairment is observed in older individuals. They found that human plasma, injected in mice, was associated with revitalization of the hippocampus with increased levels of gene expression there. Additionally, they found that behavioral measures of cognition were also improved. The protein tissue inhibitor of metalloproteinases 2 (TIMP2), was found to be implicated with these positive changes. This study has been published in Nature.
Schematic of the hippocampus. Source. - The European Ombudsman rejected a complaint by the “Stop Vivisection” European Citizens Initiative that they had not received adequate reasoning behind the decision by the European Commission to reject the initiative in July 2015. “Stop Vivisection” wanted to repeal the European animal research regulation, Directive 2010/63/EU and replace it with a proposal to speed a ban on such practices. The ombudsman noted “that the Commission has complied with its duty to explain, in a clear, comprehensible and detailed manner, its position and political choices regarding the objectives of the ECI “Stop Vivisection””.
- A new study uses your smartphone to control symptoms of diabetes. In a good example of multi-disciplinary translational medicine, and using “a multidisciplinary design principle coupling electrical engineering, software development, and synthetic biology” researchers based at the Shanghai Key Laboratory of Regulatory Biology “engineered a technological infrastructure enabling smartphone-assisted semiautomatic treatment of diabetes in mice.” Hydrogel capsules, containing cells that could produce “mouse insulin” in vivo and which contained wirelessly powered infrared LEDs were implanted in mice. Smartphones were then used to control this implant causing it to secrete “mouse insulin” as needed. Researchers were able to maintain glucose homeostasis over several weeks in the diabetic mice. This study provides a step toward translating cell-based therapies into the clinic. It also highlights that even though this technique was developed in vitro, safety and efficacy trials in animals are needed before they can be used in humans. This study was published in the journal Science.
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