Defining Subcellular Specificity of Metabotropic Glutamate Receptor (mGluR5) Antagonists

Karen O'Malley

With $217,500 in grants from FRAXA Research Foundation, Dr. Karen O’Malley and team studied the function of mGluR5 when it is inside cells. Many of the symptoms of Fragile X Syndrome (FXS) are thought to arise due to overactive metabotropic glutamate receptor 5 (mGluR5) signaling, which is normally opposed by the protein missing in FXS, Fragile X Protein (FMRP).

Read more

Mechanisms of Tolerance to Chronic mGluR5 Inhibition

Over the past few years, both Novartis and Roche sponsored large-scale clinical trials of metabotropic glutamate receptor 5 (mGlu5) negative allosteric modulators (NAMs) to treat Fragile X syndrome (FXS). With a $90,000 grant from FRAXA Research Foundation in 2015-2017, Dr. Mark Bear’s team will explore if mGlu5 NAMs dosed chronically causes tolerance, and if so, how it develops and to probe new avenues to prevent or circumvent it.

Read more

Repurposing Available Drugs to Treat Fragile X Syndrome – FRAXA Initiatives

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.

Read more

NIH Investigator Carolyn Beebe Smith, PhD, Looks to Improve Sleep in Fragile X Syndrome

Our sons with Fragile X Syndrome typically go to bed early and rise early. Sometimes they jump on us while we are sleeping at 3 a.m., excited to start their day. For heaven’s sake, why? The answer may come from Carolyn Beebe Smith, PhD, senior investigator, Section on Neuroadaptation and Protein Metabolism, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland. She is studying why children, in particularly boys, with FXS have problems sleeping.

Read more

Repurposing Drugs to Dampen Hyperactive Nonsense-Mediated Decay in Fragile X Syndrome

With a $90,000 grant from the FRAXA Research Foundation, Dr. Lynne Maquat and Dr. Tatsuaki Kurosaki will investigate nonsense-mediated mRNA decay (NMD) in Fragile X. NMD is a “housekeeping” process that cells use to prevent faulty proteins from being made. But there is too much of it in Fragile X syndrome. There are already available drugs that suppress NMD – including caffeine.

Read more

Kimberly Huber, PhD, Explores Hyperexcitability in Fragile X Syndrome

Dr. Kimberly Huber

Ever wonder why your child with Fragile X suddenly screams for no apparent reason or jumps and flaps uncontrollably seemingly for hours? You got it: hyperexcitability. But what exactly causes it? And what can fix it? Kimberly Huber, PhD, is working long and hard in her lab to answer those questions. Dr. Huber, professor, Neuroscience, UT Southwestern Medical Center, is seeking to understand how FMRP regulates connections between brain cells, called synapses, and the function of brain circuits, which are several connected brain cells.

Read more

Cornell University Researcher Looks to Restore Fragile X Protein in Neurons

Which is the right FMRP for therapeutic development of Fragile X syndrome? When researchers develop effective drugs that reactivate FMRP — the protein that is normally silenced in Fragile X — what in the world will they do next? So ponders Cornell University researcher Samie R. Jaffrey, MD, PhD. Jaffrey, professor, Pharmacology, Weill Cornell Medical College, Cornell University, knows reactivating FMRP will lead to many important questions, such as: Which cell type needs FMRP? How much FMRP protein is needed to restore brain function? Where in the brain will FMRP protein be needed? Where in a neuron will the FMRP needs to be expressed?

Read more

Researcher David Nelson, PhD, Explores New Cell Strategies for Fragile X Syndrome, FXTAS and FXPOI

David Nelson lab

It’s rare to find a researcher working on the Big Three — Fragile X Syndrome (FXS), Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) and Fragile X-associated primary ovarian insufficiency (FXPOI). Then again, David Nelson, PhD, is the rare bird. Nelson is a professor of Molecular and Human Genetics, Baylor College of Medicine, and director of Baylor’s Graduate Program in Integrative Molecular and Biomedical Sciences. He has been involved in FXS research since the late 1980s where he helped identify the mutation and the FMR1 gene. These days, researchers in Nelson’s lab at Baylor are studying FXS, FXTAS and FXPOI using mouse models.

Read more

Neuren’s Tofinetide Successful in Phase 2 Clinical Trial in Fragile X

neuren Fragile X trial result graph

We are pleased to share great news adapted from Neuren’s press release: Neuren’s phase 2 trial has successfully established proof of concept and provides a strong rationale for Neuren to move forward with developing trofinetide for Fragile X syndrome. In this initial small trial with a relatively short treatment period, trofinetide was very well tolerated, with the high dose (70 mg/kg twice daily) demonstrating a consistent pattern of clinical improvement, observed in both clinician and caregiver assessments.

Read more

FRAXADev – Developing BK Channel Openers for Fragile X Syndrome

A number of people have asked us about FRAXADev, a new project starting in France; this is a nonprofit initiative which seeks to develop a new kind of drug for Fragile X. The drugs they are interested in testing in Fragile X clinical trials were developed by Bristol-Myers Squibb many years ago, and are now off patent. This class of drugs opens a potassium channel in the membrane of neurons, which helps to decrease neuronal excitability.

Read more

Fruit Flies to Model and Test Fragile X Treatments

Dr. Tom Jongens and Dr. Sean McBride study Fragile X Fruit Flies

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.

Read more