neural progenitor cells
There’s been considerable debate about whether the human brain has the capacity to make new neurons into adulthood. Now, a recently published study offers some compelling new evidence that’s the case. In fact, the latest findings suggest that a healthy person in his or her seventies may have about as many young neurons in a portion of the brain essential for learning and memory as a teenager does.
As reported in the journal Cell Stem Cell, researchers examined the brains of healthy people, aged 14 to 79, and found similar numbers of young neurons throughout adulthood . Those young neurons persisted in older brains that showed other signs of decline, including a reduced ability to produce new blood vessels and form new neural connections. The researchers also found a smaller reserve of quiescent, or inactive, neural stem cells in a brain area known to support cognitive-emotional resilience, the ability to cope with and bounce back from stressful circumstances.
While more study is clearly needed, the findings suggest healthy elderly people may have more cognitive reserve than is commonly believed. However, the findings may also help to explain why even perfectly healthy older people often find it difficult to face new challenges, such as travel or even shopping at a different grocery store, that wouldn’t have fazed them earlier in life.
Tags: aging, aging brain, angiogenesis, autopsy study, brain, Brain Collection of the New York State Psychiatric Institute at Columbia University, cognition, dentate gyrus, elderly, glial cells, hippocampus, longevity, memory, neural progenitor cells, neural stem cells, neurogenesis, neurology, neurons, neuroplasticity, stereology
In response to the health threat posed by the recent outbreak of Zika virus in Latin America and its recent spread to Puerto Rico and Florida, researchers have been working at a furious pace to learn more about the mosquito-borne virus. Considerable progress has been made in understanding how Zika might cause babies to be born with unusually small heads and other abnormalities and in developing vaccines that may guard against Zika infection.
Still, there remains an urgent need to find drugs that can be used to treat people already infected with the Zika virus. A team that includes scientists at NIH’s National Center for Advancing Translational Sciences (NCATS) now has some encouraging news on this front. By testing 6,000 FDA-approved drugs and experimental chemical compounds on Zika-infected human cells in the lab, they’ve shown that some existing drugs might be repurposed to fight Zika infection and prevent the virus from harming the developing brain . While additional research is needed, the new findings suggest it may be possible to speed development and approval of new treatments for Zika infection.
Tags: Aedes mosquito, birth defects, CDK inhibitors, drug repurposing, drug screening, Ebola virus, emiricasan, microcephaly, mosquito, neural progenitor cells, niclosamide, organoids, PHA-690509, repurposing drugs, small-molecule inhibitors, vaccine, virology, Zika, Zika vaccine, Zika virus
A lot of time, money, and effort are devoted to developing new drugs. Yet only one of every 10 drug candidates entering human clinical trials successfully goes on to receive approval from the Food and Drug Administration (FDA) . Many would-be drugs fall by the wayside because they prove toxic to the brain, liver, kidneys, or other organs—toxicity that, unfortunately, isn’t always detected in preclinical studies using mice, rats, or other animal models. That explains why scientists are working so hard to devise technologies that can do a better job of predicting early on which chemical compounds will be safe in humans.
As an important step in this direction, NIH-funded researchers at the Morgridge Institute for Research and University of Wisconsin-Madison have produced neural tissue chips with many features of a developing human brain. Each cultured 3D “organoid”—which sits comfortably in the bottom of a pea-sized well on a standard laboratory plate—comes complete with its very own neurons, support cells, blood vessels, and immune cells! As described in Proceedings of the National Academy of Sciences , this new tool is poised to predict earlier, faster, and less expensively which new or untested compounds—be they drug candidates or even ingredients in cosmetics and pesticides—might harm the brain, particularly at the earliest stages of development.
Tags: Autism Spectrum Disorder, brain, brain development, brain on a chip, drug development, drug screening, human brain, human on a chip, machine learning, microglia, neural constructs, neural progenitor cells, neural support cells, neural tissue chip, neurodevelopmental disorders, neurology, neurons, neurotoxicity, organoid, RNA sequencing, stem cells, tissue chip, Tissue Chip for Drug Screening Program