Dave Bjork, Director of Community Relations, recently sat down with Peter Todd, MD, PhD, Assistant Professor in the Department of Neurology in the University of Michigan Medical School. Dr. Todd was recently awarded a FRAXA Research Grant for gene reactivation with the use of CRISPR. In this interview he tells us about CRISPR in Fragile X research, how realistic is it that it could turn the Fragile X gene back on, and if it can really be a cure for Fragile X.
With funding from FRAXA, the Yale University team of Leonard Kaczmarek, PhD showed that the firing pattern of suditory neurons in response to repeated stimulation is severely abnormal in Fragile X mice. Based on these results, they are collaborating with the UK-based company Autifony to develop advanced compounds which may reverse these deficits.
Although the clinical trials failed to show efficacy in the patient population and Novartis and Roche discontinued their Fragile X development programs, Dr. Senter has worked with Mark Bear, PhD to carefully review parent observations. Those caregiver reports suggested tolerance to mGlu5 antagonists antagonists developed quickly, consistent with some preclinical findings in the mouse model.
FRAXA Research Foundation was founded in 1994 to fund biomedical research aimed at finding a cure for Fragile X syndrome and, ultimately, autism. We prioritize translational research with the potential to lead to improved treatments for Fragile X in the near term. Our early efforts involved supporting a great deal of basic neuroscience to understand the cause of Fragile X. By 1996, these efforts had already begun to yield results useful for drug repurposing. To date, FRAXA has funded well over $25 million in research, with over $3 million of that for repurposing existing drugs for Fragile X. Here are some examples of FRAXA-funded work on repurposing available drugs for Fragile X syndrome: Lithium In the mid-1990s, the Greenough lab at the University of Illinois discovered that FMRP, the protein missing in Fragile X, is rapidly translated in dendrites in response to stimulation of glutamate receptors. FRAXA funded preclinical validation of this discovery in theRead more
Massachusetts Institute of Technology Researcher Mark Bear, PhD, Sees Success Developing Disease-Modifying Treatments for Fragile X Syndrome and Other Developmental Brain Disorders Finally, hope. And it comes from the lab of Mark Bear, PhD, Picower Professor of Neuroscience, The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology Dr. Bear is building on the “mGluR theory” and applied insights gained by the study of Fragile X and other genetically defined causes of intellectual disability and autism with some success. His goal is to discover and facilitate the development of disease-modifying treatments for Fragile X and other developmental brain disorders. “Neurons in the brain communicate with each other at specialized junctions called synapses,” said Bear, who earned a BS from Duke University and a PhD in neurobiology at Brown University. “Such modifications are the basis for memory storage in the brain, and go awryRead more
FRAXA Fellowship Awarded May 2016, Renewed May 2017 Enhancement of NMDA Receptor Signaling for the Treatment of Fragile X Syndrome Principal Investigator Emily Osterweil, PhD Postdoctoral Fellow Stephanie Barnes, PhD University of Edinburgh $90,000 over 2 years University of Edinburgh Researcher Emily Osterweil, PhD, Probes the Brain’s Biochemistry to Correct Imbalances We know the “X” in Fragile X refers to the X chromosome, but it could just as easily refer to the unknown.Such as why do people with Fragile X have an excessive production of new proteins in their brains that lead to imbalances? That question is being dissected in the lab of Emily Osterweil, PhD, chancellor’s fellow, Centre for Integrative Physiology, University of Edinburgh, UK. Dr. Osterweil is using insights from previous experiments to identify new treatment strategies for Fragile X. Her goal is to understand the biochemistry of the brain better. She aims to correct those imbalances byRead more
With a $110,050 grant from FRAXA Research Foundation from 2005-2016, Dr. Sumantra Chattarji at the National Center for Biological Sciences researched how the amygdala is affected by Fragile X syndrome. Results published.
With a $100,000 grant from the FRAXA Research Foundation in 2015, Dr. Peter Vanderklish explored a novel strategy to treat Fragile X syndrome: AMPK activators. The good news is that there are FDA approved (for example, metformin) and naturally occurring AMPK activators (such as resveratrol, found in red wine).
Dr. Jongens and his collaborators have found an insulin-like protein in the fly brain that is overexpressed in the Fragile X mutant fly, leading to increased activity of the insulin signaling pathway. Furthermore, they found that certain behavioral patterns in the Fragile X flies can be rescued by expressing the FX gene just in insulin producing neurons in the fly brain. In the mutant, there are other changes in the signaling pathways, including a decrease in cAMP and elevation in PI3K, mTOR, Akt and ERK activity. They now propose to study 2 medicines used for diabetes: pioglitazone (increases cAMP and decreases Akt and ERK) and metformin (inhibits mTOR), in flies and mice to validate the potential efficacy of these novel therapeutics for Fragile X.
Re-examining the Nature of Fragile X In the wake of negative results from several high-profile clinical trials in Fragile X, we find ourselves questioning many of our previous assumptions about the nature of this disorder. After all, understanding the basic pathology of disease is critical to development of new treatments — this is true across the board, in all branches of medicine. In the early days of Fragile X research, shortly after the FMR1 gene was discovered and the normal protein product of the gene (FMRP) was identified, it was noted that FMRP is an RNA binding protein. Whatever the normal function of this single protein which Fragile X patients lack, it had something to do with RNA metabolism. Since RNA is the template used to make new proteins, this meant that the Fragile X protein is involved in regulating protein synthesis. A synapse showing the axon of neuron 1,Read more
Studies have shown that the function of inhibitory networks is disturbed in Fragile X. This abnormality is not well understood but appears to be secondary to abnormalities in metabotropic glutamate and endocannabinoid systems. With a $90,000 grant from FRAXA in 2013-2014, Dr. Molly Huntsman’s team examined how these networks interact and how inhibitory deficits can best be remedied.
With a $90,000 grant from the FRAXA Research Foundation, Dr. Robert Wong is investigating how seizures are generated in Fragile X neurons. More generally, he is looking at how synapses are modified to enable learning and memory and how this process is impaired in Fragile X. $90,000 Grant Robert Wong, PhD Principal Investigator State University of New York 2013-2014 FRAXA Research Grant $90,000 over 2 Years Abnormal increases in sensitivity of a type of glutamate receptor (group I mGluR) cause brain malfunction, including epilepsy, in Fragile X syndrome (FXS). We are examining a newly uncovered regulation of this increased group I mGluR sensitivity by a second type of glutamate receptor, the NMDA receptor. By looking at audiogenic seizures in FXS model mice, NMDA receptor blockers were found to robustly suppress these seizures at the young developmental stage. In contrast, the same antagonists activated seizure activities, normally dormant, in adult FXS model mice and in a CGGRead more
Drug Tolerance and Dose Range Problems May Have Been the CulpritsAndy Tranfaglia and his dad, Mike Tranfaglia In my opinion, the Fragile X clinical trials of AFQ056 sponsored by Novartis failed because of a dose range that was inadequate for Fragile X, and because of the unexpected development of tolerance. Dosage problems are relatively easy to correct, but tolerance to the degree we observed may be a kind of fatal flaw, at least if we're talking about mGluR5 antagonists. The mGluR Theory of Fragile X is still probably correct; it's just that no one (least of all Novartis) expected tolerance to this drug -- indeed, I'm not sure they would agree that's what happened. I think we saw a much better response than most people because our son, Andy, was also on minocycline, effectively augmenting the response, and perhaps delaying the development of tolerance. This may be a clue to understanding the mechanism of tolerance,Read more
Funding Priorities for 2014 Grant Cycle We anticipate particularly keen competition for funding in this grant cycle. Challenging economic times inevitably force us back to fundamental principles, and so our overall priorities for 2014 grants will be to bring new, high-quality scientists into the Fragile X field, and to promote translational, preclinical, and clinical research with the greatest chance of improving therapeutics for those living with Fragile X. Here are a few key implications of these policies: We want new ideas! The mGluR Theory is now being tested in the clinic; we do not anticipate funding any major new projects investigating mGluR5 function, although there are many possible spin-off projects which could be the basis for successful applications. Likewise, we do not assign a high priority to studies of every element of mGluR-coupled signaling pathways, unless the topic of study is an especially druggable target. Most components of signaling pathways inRead more
Available Medication Lovastatin Corrects Excess Protein Synthesis in Fragile X Mice Dr. Emily Osterweil At the opening dinner of the 2011 FRAXA Investigators Meeting in Southbridge, MA, Dr. Emily Osterweil was awarded the FRAXA Pioneer Award for work demonstrating that Lovastatin could treat Fragile X. Dr. Osterweil conducted her experiments in the MIT laboratory of Dr. Mark Bear; she has since established her own laboratory at the University of Edinburgh. The team discovered that lovastatin, a drug widely prescribed for high cholesterol, can correct excess hippocampal protein synthesis in the mouse model of FXS and can prevent epileptogenesis. The work is published in the prestigious neuroscience journal Neuron: Lovastatin Corrects Excess Protein Synthesis and Prevents Epileptogenesis in a Mouse Model of Fragile X Syndrome. One implication of the mGluR theory of Fragile X is that there are exaggerated consequences of activation of signaling pathways which link metabotropic glutamate receptors (mGluRs) to the cellular machinery ofRead more
With a $90,000 grant from FRAXA Research Foundation over two years, Drs. Olivier Manzoni and Daniela Neuhofer researched the relationship between Fragile X syndrome and the areas of the brain that are involved in reward processing, regulation of emotional behavior and emotional memory as well as attention, planning and working memory.
With a $474,300 grant from FRAXA Research Foundation from 2000-2013, Dr. Kimberly Huber and her team at the University of Texas conducted several studies on the relationship between mGluR5 and Fragile X syndrome. Dr. Huber made the original discovery of the mGluR Theory of Fragile X when she was a postdoctoral fellow in the lab of Dr. Mark Bear, with her first FRAXA grant in 2000.
With a $66,000 grant from FRAXA Research Foundation in 2013, Dr. Lucia Ciranna and her team from the Universita di Catania tested if specific serotonins could reverse abnormal phentotypes found in Fragile X syndrome.
With $384,345 in grants from FRAXA Research Foundation, Dr. MariVi Tejada from the University of Houston focused on a particularly promising point of intervention in pathways of brain receptors, and tested several potential therapeutic compounds in an attempt to rescue function in the mouse model of Fragile X.
Dr. Huber made the original discovery of the mGluR Theory of Fragile X when she was a postdoctoral fellow in the lab of Dr. Mark Bear, with her first FRAXA grant in 2000. Dr. Huber has received $474,300 in grants from FRAXA Research Foundation since then, researching molecular mechanisms and developmental switches in Fragile X syndrome. She has worked with 4 FRAXA Postdoctoral Fellows (Elena Nosyreva, PhD in 2006; Jennifer Roseni, PhD in 2007; Tong Zang, PhD in 2010-2011; and Weirui Guo, PhD in 2012-2013) and has received supporting funds from The Meadows Foundation of/for Texas.
With a $120,000 grant from FRAXA Research Foundation during 2011-2012, Dr. Cara Westmark at the University of Wisconsin explored the role of AbPP as a potential treatment option for fragile X. AbPP produces b-amyloid which is over-expressed in Alzheimer’s disease (AD) and Down syndrome.
With a $163,356 grant from FRAXA Research Foundation in 2010-12, Dr. Scott Soderling and Dr. Hwan Kim at Duke University bred the standard mouse model of Fragile X syndrome to their lines of mice that express reduced levels of several key proteins that modulate synaptic actin. These compound mutant mice were compared to FXS mice to determine if genetically impairing pathways to the actin cytoskeleton can rescue deficits in the FXS mice.
A study finds that a new compound reverses many of the major symptoms associated with Fragile X syndrome (FXS). The paper is published in the April 12 issue of the journal Neuron, describes the exciting observation that the FXS correction can occur in adult mice, after the symptoms of the condition have already been established. Previous research has suggested that inhibition of mGlu5, a subtype of receptor for the excitatory neurotransmitter glutamate, may ameliorate many of the major symptoms of the disease. This study, a collaboration between a group at Roche in Switzerland, led by Dr. Lothar Lindemann, and Dr. Mark Bear’s MIT lab, used an mGlu5 inhibitor called CTEP to examine whether inhibition of mGlu5 could reverse FXS symptoms. The researchers gave CTEP to mice which model Fragile X. "We found that even when treatment with CTEP was started in adult mice, it reduced a wide range of FXSRead more
With a $90,000 grant from FRAXA Research Foundation over 2 years, Dr. Michael Wilhelm and his team at the University of Wisconsin studied a protein known as JNK, which is observed to be abnormally regulated in Fragile X. Like FMRP, it is involved in regulating dendritic protein synthesis, and so it may be a target for drug therapy in Fragile X.
With a $90,000 grant from FRAXA Research Foundation in 2010-2011, Dr. Mark Bear and Dr. Miquel Bosch tested the simple hypothesis that the excessive rate of protein synthesis is not a consequence but the primary cause of the structural alterations occurring in Fragile X syndrome.