Posted on by Dr. Francis Collins
August is here, and many folks have plans to enjoy a well-deserved vacation this month. I thought you might enjoy taking a closer look during August at the wonder and beauty of the brain here on my blog, even while giving your own brains a rest from some of the usual work and deadlines.
Some of the best imagery—and best science—comes from the NIH-led Brain Research through Advancing Innovative Neurotechnologies® (BRAIN) Initiative, a pioneering project aimed at revolutionizing our understanding of the human brain. Recently, the BRAIN Initiative held a “Show Us Your Brain Contest!”, which invited researchers involved in the effort to submit their coolest images. So, throughout this month, I’ve decided to showcase a few of these award-winning visuals.
Let’s start with the first-place winner in the still-image category. What you see above is an artistic rendering of deep brain stimulation (DBS), an approach now under clinical investigation to treat cognitive impairment that can arise after a traumatic brain injury and other conditions.
The vertical lines represent wire leads with a single electrode that has been inserted deep within the brain to reach a region involved in cognition, the central thalamus. The leads are connected to a pacemaker-like device that has been implanted in a patient’s chest (not shown). When prompted by the pacemaker, the leads’ electrode emits electrical impulses that stimulate a network of neuronal fibers (blue-white streaks) involved in arousal, which is an essential component of human consciousness. The hope is that DBS will improve attention and reduce fatigue in people with serious brain injuries that are not treatable by other means.
Andrew Janson, who is a graduate student in Christopher Butson’s NIH-supported lab at the Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, composed this image using a software program called Blender. It’s an open-source, 3D computer graphics program often used to create animated films or video games, but not typically used in biomedical research. That didn’t stop Janson.
With the consent of a woman preparing to undergo experimental DBS treatment for a serious brain injury suffered years before in a car accident, Janson used Blender to transform her clinical brain scans into a 3D representation of her brain and the neurostimulation process. Then, he used a virtual “camera” within Blender to capture the 2D rendering you see here. Janson plans to use such imagery, along with other patient-specific modeling and bioelectric fields simulations, to develop a virtual brain stimulation surgery to predict the activation of specific fiber pathways, depending upon lead location and stimulation settings.
DBS has been used for many years to relieve motor symptoms of certain movement disorders, including Parkinson’s disease and essential tremor. More recent experimental applications include this one for traumatic brain injury, and others for depression, addiction, Alzheimer’s disease, and chronic pain. As the BRAIN Initiative continues to map out the brain’s complex workings in unprecedented detail, it will be exciting to see how such information can lead to even more effective applications of to DBS to help people living with a wide range of neurological conditions.
Deep Brain Stimulation for Movement Disorders (National Institute of Neurological Disorders and Stroke/NIH)
Video: Deep Brain Stimulation (University of Utah, Salt Lake City)
Butson Lab (University of Utah)
Show Us Your Brain! (BRAIN Initiative/NIH)
NIH Support: National Institute of Neurological Disorders and Stroke
Posted on by Dr. Francis Collins
A few weeks ago, I was pleased to take part in the announcement of NIH’s HEALing Communities Study in four states hard hit by the opioid epidemic. This study will test a comprehensive, evidence-based approach—which includes the wide distribution of naloxone to reverse overdoses—with the aim of reducing opioid-related deaths in selected communities by 40 percent over three years.
That’s a very ambitious goal. So, I was encouraged to read about new findings that indicate such reductions may be within our reach if society implements a number of key changes. Among those is the need to arm friends, family members, and others with the ability to save lives from opioid overdoses. Between 2013 and 2016, nine states instituted laws that give pharmacists direct authority to dispense naloxone to anyone without a prescription. However, the impact of such changes has remained rather unclear. Now, an NIH-funded analysis has found that within a couple of years of these new laws taking effect, fatal opioid overdoses in these states fell significantly .
The misuse and overuse of opioids, which include heroin, fentanyl, and prescription painkillers, poses an unprecedented public health crisis. Every day, more than 130 people in the United States die from opioid overdoses . Not only are far too many families losing their loved ones, this crisis is costing our nation tens of billions of dollars a year in lost productivity and added expenses for healthcare, addiction treatment, and criminal justice.
Opioid overdoses lead to respiratory arrest. If not reversed in a few minutes, this will be fatal. In an effort to address this crisis, the federal government and many states have pursued various strategies to increase access to naloxone, which is a medication that can quickly restore breathing in a person overdosing on opioids. Naloxone, which can be delivered via nasal spray or injection, works by binding opioid receptors to reverse or block the effect of opioids. The challenge is to get naloxone to those who need it before it’s too late.
In some states, a physician still must prescribe naloxone. In others, naloxone access laws (NALs) have given pharmacists the authority to supply naloxone without a doctor’s orders. But not all NALs are the same.
Some NALs, including those in Alaska, California, Connecticut, Idaho, New Mexico, North Dakota, Oklahoma, Oregon, and South Carolina, give pharmacists direct authority to dispense naloxone to anyone who requests it. But NALs in certain other states only give pharmacists indirect authority to dispense naloxone to people enrolled in certain treatment programs, or who meet other specific criteria.
In the new analysis, published in JAMA Internal Medicine, a team that included Rahi Abouk, William Paterson University, Wayne, NJ, and Rosalie Liccardo Pacula and David Powell, RAND Corp., Arlington, VA, asked: Do state laws to improve naloxone access lead to reductions in fatal overdoses involving opioids? The answer appears to be “yes,” but success seems to hinge on the details of those laws.
The evidence shows that states allowing pharmacists direct authority to dispense naloxone to anyone have seen large increases in the dispensing of the medication. In contrast, states granting pharmacists’ only indirect authority to dispense naloxone have experienced little change.
Most importantly, the research team found that states that adopted direct authority NALs experienced far greater reductions in opioid-related deaths than states with indirect authority NALs or no NALs. Specifically, the analysis showed that in the year after direct authority NALs were enacted, fatal opioid overdoses in those states fell an average of 27 percent, with even steeper declines in ensuing years. Longer-term data are needed, and, as in all observational studies of this sort, one must be careful not to equate correlation with causation. But these findings are certainly encouraging.
There were some other intriguing trends. For instance, the researchers found that states that allow pharmacists to dispense naloxone without a prescription also saw an increase in the number of patients treated at emergency departments for nonfatal overdoses. This finding highlights the importance of combining strategies to improve naloxone access with other proven interventions and access to medications aimed to treat opioid addiction. Integration of all possible interventions is exactly the goal of the HEALing Communities Study mentioned above.
Successfully tackling the opioid epidemic will require a multi-pronged approach, including concerted efforts and research advances in overdose reversal, addiction treatment, and non-addictive pain management . As I’ve noted before, we cannot solve the opioid addiction and overdose crisis without finding innovative new ways to treat pain. The NIH is partnering with pharmaceutical industry leaders to accelerate this process, but it will take time. The good news based on this new study is that, with thoughtful strategies and policies in place, many of the tools needed to help address this epidemic and save lives may already be at our disposal.
 Association Between State Laws Facilitating Pharmacy Distribution of Naloxone and Risk of Fatal Overdose. Abouk R, Pacula RL, Powell D. JAMA Intern Med. 2019 May 6
 Opioid Overdose Crisis. National Institute on Drug Abuse/NIH. Updated January 2019.
Naloxone for Opioid Overdose (National Institute on Drug Abuse/NIH)
NIH Support: National Institute on Drug Abuse
Posted on by Dr. Francis Collins
Serotonin is best known for its role as a chemical messenger in the brain, helping to regulate mood, appetite, sleep, and many other functions. It exerts these influences by binding to its receptor on the surface of neural cells. But startling new work suggests the impact of serotonin does not end there: the molecule also can enter a cell’s nucleus and directly switch on genes.
While much more study is needed, this is a potentially groundbreaking discovery. Not only could it have implications for managing depression and other mood disorders, it may also open new avenues for treating substance abuse and neurodegenerative diseases.
To understand how serotonin contributes to switching genes on and off, a lesson on epigenetics is helpful. Keep in mind that the DNA instruction book of all cells is essentially the same, yet the chapters of the book are read in very different ways by cells in different parts of the body. Epigenetics refers to chemical marks on DNA itself or on the protein “spools” called histones that package DNA. These marks influence the activity of genes in a particular cell without changing the underlying DNA sequence, switching them on and off or acting as “volume knobs” to turn the activity of particular genes up or down.
The marks include various chemical groups—including acetyl, phosphate, or methyl—which are added at precise locations to those spool-like proteins called histones. The addition of such groups alters the accessibility of the DNA for copying into messenger RNA and producing needed proteins.
In the study reported in Nature, researchers led by Ian Maze and postdoctoral researcher Lorna Farrelly, Icahn School of Medicine at Mount Sinai, New York, followed a hunch that serotonin molecules might also get added to histones . There had been hints that it might be possible. For instance, earlier evidence suggested that inside cells, serotonin could enter the nucleus. There also was evidence that serotonin could attach to proteins outside the nucleus in a process called serotonylation.
These data begged the question: Is serotonylation important in the brain and/or other living tissues that produce serotonin in vivo? After a lot of hard work, the answer now appears to be yes.
These NIH-supported researchers found that serotonylation does indeed occur in the cell nucleus. They also identified a particular enzyme that directly attaches serotonin molecules to histone proteins. With serotonin attached, DNA loosens on its spool, allowing for increased gene expression.
The team found that histone serotonylation takes place in serotonin-producing human neurons derived from induced pluripotent stem cells (iPSCs). They also observed this process occurring in the brains of developing mice.
In fact, the researchers found evidence of those serotonin marks in many parts of the body. They are especially prevalent in the brain and gut, where serotonin also is produced in significant amounts. Those marks consistently correlate with areas of active gene expression.
The serotonin mark often occurs on histones in combination with a second methyl mark. The researchers suggest that this double marking of histones might help to further reinforce an active state of gene expression.
This work demonstrates that serotonin can directly influence gene expression in a manner that’s wholly separate from its previously known role in transmitting chemical messages from one neuron to the next. And, there are likely other surprises in store.
The newly discovered role of serotonin in modifying gene expression may contribute significantly to our understanding of mood disorders and other psychiatric conditions with known links to serotonin signals, suggesting potentially new targets for therapeutic intervention. But for now, this fundamental discovery raises many more intriguing questions than it answers.
Science is full of surprises, and this paper is definitely one of them. Will this kind of histone marking occur with other chemical messengers, such as dopamine and acetylcholine? This unexpected discovery now allows us to track serotonin and perhaps some of the brain’s other chemical messengers to see what they might be doing in the cell nucleus and whether this information might one day help in treating the millions of Americans with mood and behavioral disorders.
 Histone serotonylation is a permissive modification that enhances TFIID binding to H3K4me3. Farrelly LA, Thompson RE, Zhao S, Lepack AE, Lyu Y, Bhanu NV, Zhang B, Loh YE, Ramakrishnan A, Vadodaria KC, Heard KJ, Erikson G, Nakadai T, Bastle RM, Lukasak BJ, Zebroski H 3rd, Alenina N, Bader M, Berton O, Roeder RG, Molina H, Gage FH, Shen L, Garcia BA, Li H, Muir TW, Maze I. Nature. 2019 Mar 13. [Epub ahead of print]
Any Mood Disorder (National Institute of Mental Health/NIH)
Drugs, Brains, and Behavior: The Science of Addiction (National Institute on Drug Abuse/NIH)
Epigenomics (National Human Genome Research Institute/NIH)
Maze Lab (Icahn School of Medicine at Mount Sinai, New York, NY)
NIH Support: National Institute on Drug Abuse; National Institute of Mental Health; National Institute of General Medical Sciences; National Cancer Institute
Posted on by Dr. Francis Collins
Writers have The Elements of Style, chemists have the periodic table, and biomedical researchers could soon have a comprehensive reference on how to make neurons in a dish. Kristin Baldwin of the Scripps Research Institute, La Jolla, CA, has received a 2016 NIH Director’s Pioneer Award to begin drafting an online resource that will provide other researchers the information they need to reprogram mature human skin cells reproducibly into a variety of neurons that closely resemble those found in the brain and nervous system.
These lab-grown neurons could be used to improve our understanding of basic human biology and to develop better models for studying Alzheimer’s disease, autism, and a wide range of other neurological conditions. Such questions have been extremely difficult to explore in mice and other animal models because they have shorter lifespans and different brain structures than humans.
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