Tag Archives: lamb

Research Roundup: An artificial womb for preemie lambs, umbilical cord protein enhances cognition, smartphones to control diabetes, 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.

  • 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.

    hippocampus

    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.
Apr27_2017_ShanghaiKeyLabOfRegulatoryBiology_DiabeticMouseSmartPhone2447847722.jpg

Photo courtesy of Shanghai Key Laboratory of Regulatory Biology

Animal Research Benefits Mom and Baby Alike

The contributions of animal research to human health are many.

In response to blanket statement that animal research “does not work” I wanted to provide three examples of how animal research has directly benefited the health of women and their babies: in-vitro fertilization, oral contraceptives and neonatal intensive care.

Do you or any of your friends conceived with help of in-vitro fertilization?  Do you know how the method was developed?

It turns out that rabbits played a central role in the development of in-vitro fertilization.   As far abck as 1891 Walter Heape in England reported the first known case of embryo transplantation from one rabbit species to another, thereby showing that it was possible to transfer the embryos to a gestational carrier without adverse effects.  In 1934 Dr. Gregory Pincus at Harvard achieved in-vitro fertilization in rabbits for the first time, and he made very detailed studies in animals of the effects of hormones on ovulation and early embryonic development.  Being ahead of his time brought him much negative reputation and was described by the media a modern “Dr. Frankestein” (in fact, he was denied tenure due to these experiments.)   In 1958 Dr. Min Chueh Chang demonstrated conclusively that IVF was possible by implanting black rabbit embryos conceived in the lab into a white rabbit.  His studies in rabbits, rats, mice and hamsters during the 1950’s, 60’s, and 70’s, identified key conditions for IVF to be successful, such as the need for sperm capacitation.  These findings paved the way for the development of in-vitro fertilization in humans by Dr. Robert Edwards and Dr. Patrick Steptoe, which allows families to have a children overcoming many obstacles to pregnancy, both in cases of female and male infertility.  Approximately 60,000 infants are born with the help of IVF in the US every year…   Thank the rabbits.

Have you ever asked yourself where oral contraceptives come from?

The “pill” was first introduced in the 60s based on synthetic hormones that mimic the way progesterone works to prevent ovulation.  In 1919 Dr Ludwig Haberlandt and colleagues first demonstrated that transplantation of ovaries of pregnant rabbits into fertile female rabbits suppressed their ovulation.   Shortly before his death Haberlandt was able to prevent pregnancy in mice through the oral administration of an extract from the ovaries. It later was discovered that this was caused by the hormone progesteroneMargaret Sanger, the famous American birth control activist,  asked Dr. Gregory Pincus (the same one that developed IFV) to think of new methods of contraception and, building on these results, he showed that repeated injections of progesterone indeed could stop ovulation in rabbits.   This key finding, along with the development of a synthetic version of progesterone, led the first clinical trials of “the pill” in Puerto Rico.   Identifying effective synthetic progesterones was not an easy task, Dr. Pincus and Dr. Chang screened over 200 candidates before identifying three that prevented ovulation in laboratory animals.  The subsequent clinical trials of one of these synthetic progesterones were successful and Enovid was approved by the FDA in 1957.   Thank the rabbits again…

Dr Gregory Pincus and Dr Min Chueh Chang, pictured alongside artificial insemination pioneer Sir John Hammond. Courtesy of Mrs. F. Hammond.

Have you any of your friends had a premature baby in the intensive care unit?   Do you know why survival rates are now much higher than in the past?

The rate of premature birth has increased by 36% since the 80s (1).  Most babies born before 37 weeks of pregnancy are premature and are at risk of many complications.  In the USA alone, about 12.8% of babies are born prematurely and will spend their first few days of their lives in the neonatal intensive care unit.  Among babies born before the 34th week, 23,000 a year of them suffer from respiratory distress syndrome (RDS).  Such babies lack a protein in their lungs (called surfactants) that keep the air sacs in the lungs from collapsing.

Surfactants were discovered and their chemical composition analyzed using dogs in biomedical research and through research on rabbits and lambs surfactant therapy, initially using surfactant from cows and later synthetic surfactant, was developed.  The fruits of this research were translated into the treatments using surfactants in the 90s, which reduced the death of babies from RDS by about 50% (2).  In other words, slightly more than 10,000 babies are saved every year just in the US alone due to surfactant-replacement therapy.

That’s more than one baby per hour just in the US… Saved.  Thanks to animal research.

And this work goes on, for example in recent posts Paul has discussed the use of brain cooling and xenon gas to protect babies who have suffered oxygen starvation during birth from brain damage.

So when animal rights activists and the medical wing of their movement state that animal research “does not work”, what they really mean is that it does not work… for them.

Yet, they cannot deny these facts with books full of half-truths and out-of-context citations.

Anyone can walk into the nearest neonatal ICU and face the babies and their parents.  Face the facts.

Dario Ringach

References:

(1) Martin, J.A., et al. Births: Final Data for 2006. National Vital Statistics Reports, volume 57, number 7, January 7, 2008.

(2) Engle, W.A., and the Committee on Fetus and Newborn. Surfactant-Replacement Therapy for Respiratory Distress in the Preterm and Term Neonate. Pediatrics, volume 121, number 2, February 2008, pages 419-428