Breaking News
March 25, 2019 - Tighter Blood Pressure Control May Prevent Brain Lesions
March 25, 2019 - A reward now or later? Exploring impulsivity in Parkinson’s disease patients
March 25, 2019 - Financial incentives fail to increase completion rates of colorectal cancer screening tests mailed to patients
March 25, 2019 - New research program launched to highlight sexual harassment in academia
March 25, 2019 - Hemoglobin A1c blood test does not detect diabetes in most patients, shows study
March 25, 2019 - Wyss Technology licensed by Sherlock Biosciences to create affordable molecular diagnostics
March 25, 2019 - DWK Life Sciences launches KIMBLE GLS 80 Media Bottle and Multiport Cap System
March 25, 2019 - New study aims to reduce online sexual exploitation of children
March 25, 2019 - Want healthier eating habits? Start with a workout
March 25, 2019 - New approach to prescribing antibiotics could curb resistance
March 24, 2019 - Theravance Biopharma Announces First Patient Dosed in Phase 2b/3 Study of TD-1473 in Patients with Ulcerative Colitis
March 24, 2019 - Prenatal DHA prevents blood-pressure increase from obesity during childhood
March 24, 2019 - Combined immunosuppression may be effective, safe in treating older patients with Crohn’s disease
March 24, 2019 - GSK sells health drinks arm, buys US cancer treatment firm
March 24, 2019 - Bacteria and innate immune factors in birth canal, cervix may be key to predicting preterm births
March 24, 2019 - IgG antibodies play unexpected role in atherosclerosis
March 24, 2019 - Sounds and vibrations are quite similar for the brain, finds new study
March 24, 2019 - Practices for Reducing COPD Hospital Readmissions Explored
March 24, 2019 - Could an eye doctor diagnose Alzheimer’s before you have symptoms?
March 24, 2019 - Enzyme inhibitor stops inflammation and neurodevelopmental disorders in mouse models
March 24, 2019 - Walk, Dance, Clean: Even a Little Activity Helps You Live Longer
March 24, 2019 - Americans used less eye care in 2014 versus 2008
March 24, 2019 - Study finds link between depression in 20s linked to memory loss in 50s
March 24, 2019 - New tool helps physiotherapy students to master complex fine motor skills
March 24, 2019 - The AMR Centre secures £2.3m funding boost
March 24, 2019 - Study examines effects of taking ondansetron during first trimester of pregnancy
March 24, 2019 - Researchers identify a more effective treatment for cancer
March 24, 2019 - Open-source solution for multiparametric optical mapping of the heart’s electrical activity
March 24, 2019 - New nanotechnology approach shows promise in treating triple negative breast cancer
March 24, 2019 - Trevena Announces Publication of APOLLO-1 Results in The Journal of Pain Research Highlighting Oliceridine’s Potential for Management of Moderate-to-Severe Acute Pain
March 24, 2019 - Maternal deaths following C-section 50 times higher in Africa compared to high-income countries
March 24, 2019 - Apple watch could detect irregular heart beat says study
March 24, 2019 - Queen Mary University of London’s BCI boosts radionuclide imaging capabilities with MILabs VECTor technology
March 24, 2019 - Girls should be encouraged to gain more ball skills, shows study
March 24, 2019 - Acute doses of synthetic cannabinoid can impair critical thinking and memory
March 24, 2019 - Presence of bacteria in urine does not always point to infection, shows study
March 24, 2019 - Scientists identify a new role for nerve-supporting cells
March 24, 2019 - Hidden differences between pathology of CTE and Alzheimer’s disease discovered
March 24, 2019 - Knowing causative genes of osteoporosis may open door to more effective treatments
March 24, 2019 - Toilet-seat based cardiovascular monitoring system getting ready to begin commercialization
March 24, 2019 - New model for intensive care identifies factors that send ill patients to ICU
March 24, 2019 - Recommendations Issued for HSCT in Multiple Myeloma
March 24, 2019 - Deep brain stimulation provides sustained relief for severe depression
March 24, 2019 - “Statistical significance” may soon be a thing of past?
March 24, 2019 - Researchers track effects of epigenetic marks carried by sperm chromosomes
March 24, 2019 - AHA News: Family Adopts Three Children With Three Different Heart Conditions
March 24, 2019 - Research into opioid painkillers could provide clues for safer drug development
March 23, 2019 - Lung cancer survivor recounts her lifetime struggles
March 23, 2019 - Radial and femoral approach for PCI achieve similar results in terms of survival
March 23, 2019 - Study sheds light on the optimal timing of coronary angiography in NSTEMI patients
March 23, 2019 - Excess hormones could cause a condition that can lead to blindness in women, study finds
March 23, 2019 - Dramatic shifts in first-time opioid prescriptions bring hope, concern
March 23, 2019 - Antidepressant drugs may not work when neurons are out of shape
March 23, 2019 - TTUHSC El Paso to establish endowed chair in neurology through a major grant
March 23, 2019 - New device approved by FDA for treating patients with moderate-to-severe heart failure
March 23, 2019 - People with peripheral artery disease have lower Omega-3 Index, shows research
March 23, 2019 - Trigger warnings have minimal impact on how people respond to content, shows research
March 23, 2019 - Gilead Announces Data From Two Studies Supporting Further Development of GS-6207, a Novel, Investigational HIV-1 Capsid Inhibitor as a Component of Future Long-Acting HIV Therapies
March 23, 2019 - Selfish genetic elements amplify inflammation and age-related diseases
March 23, 2019 - Study provides new understanding of how the brain recovers from damage caused by stroke
March 23, 2019 - CRISPR/Cas libraries could revolutionize drug discovery
March 23, 2019 - Allergic reaction during pregnancy may alter sexual-development in offspring’s brain
March 23, 2019 - Seeing through a robot’s eyes helps those with profound motor impairments
March 23, 2019 - Recent research shows that ease of breastfeeding after C-section differs culturally
March 23, 2019 - Newly discovered parameters offer more control over efficient release of drugs
March 23, 2019 - ‘De-tabooing’ of abortion- Women would like more support from health care community
March 23, 2019 - Anti-TB drugs can increase susceptibility to Mtb reinfection
March 23, 2019 - New survey indicates need of attention to neglected tropical diseases
March 23, 2019 - Innovative in vitro method to develop easy-to-swallow medicine for children and older people
March 23, 2019 - Sugary drinks could raise risk of early deaths finds study
March 23, 2019 - Lian wins ENGINE grant for stem-cell-based therapy to treat Type 1 diabetes
March 23, 2019 - Overall, Physicians Are Happy and Enjoy Their Lives
March 23, 2019 - Researchers discover how blood vessels protect the brain during inflammation
March 23, 2019 - CDC study shows modest improvement in optimal hospital breastfeeding policy
March 23, 2019 - Family-based prevention program to reduce alcohol use among older teens
March 23, 2019 - Remote monitoring of implanted defibrillators in heart failure patients prevents hospitalizations
March 23, 2019 - Appropriate doffing of personal protective equipment may reduce healthcare worker contamination
March 23, 2019 - Window screens can suppress mosquito populations, reduce malaria in Tanzania
March 23, 2019 - Researchers discover new biomarker for postoperative liver dysfunction
March 23, 2019 - Pregnancy history may be linked to cognitive function in older women, finds study
New drug strategy can alleviate multiple behavioral, cellular deficiencies in FXS mouse model

New drug strategy can alleviate multiple behavioral, cellular deficiencies in FXS mouse model

image_pdfDownload PDFimage_print

Research in mice shows that a pharmacological strategy can alleviate multiple behavioral and cellular deficiencies in a mouse model of fragile X syndrome (FXS), the most common inherited form of intellectual disability and a major single-gene cause of autism spectrum disorders.

The results are scheduled for publication in Neuropsychopharmacology, and are being presented at the NFXF International Fragile X Conference in Cincinnati.

When the compound GSK6A was given to mice lacking the Fmr1 gene, an established animal model of fragile X syndrome, it relieved symptomatic behaviors, such as impaired social interactions and inflexible decision making, which can be displayed by humans with fragile X syndrome.

The findings indicate that treatment with GSK6A or a similar compound could be a viable strategy for addressing cognitive and behavioral problems in fragile X syndrome; this would need to be tested directly in clinical trials. GSK6A inhibits one particular form of a cellular signaling enzyme: the p110β form of PI3 (phosphoinositide-3) kinase. A closely related p110β inhibitor is already in clinical trials for cancer.

“Our results suggest that p110β inhibitors can be repurposed for fragile X syndrome, and they have implications for other subtypes of autism spectrum disorders that are characterized by similar alterations of this pathway,” says Gary Bassell, PhD, professor and chair of cell biology at Emory University School of Medicine.

The paper represents a collaboration between three laboratories: two at Emory led by Bassell and Shannon Gourley, PhD (Gourley is based at Yerkes National Primate Research Center), and one at Cincinnati Children’s, led by Christina Gross, PhD.

“Right now, no proven efficient treatments are available for fragile X syndrome that are targeted to the disease mechanism,” Gross says. “We think that p110β is an appropriate target because it is directly regulated by FMRP, and it is overactivated in both mouse models and patient cell lines.”

While the researchers are discussing clinical trials of p110β inhibitors in fragile X syndrome, they say that long-term studies in animals are needed to ensure that undesirable side effects do not appear.

Fragile X syndrome affects around 1 in 3000 males and 1 in 6000 females, with females often having milder symptoms. Affected children display intellectual disability and delay of milestones such as speech. Fragile X syndrome frequently includes autism-like features, such as impaired social skills, gaze aversion/social anxiety, hyperactivity and repetitive behaviors.

Fragile X syndrome is caused by silencing of a single gene, FMR1, preventing production of an RNA binding protein, FMRP. FMRP controls the production of several proteins at synapses, the sites of communication between neurons.

The mouse studies described in the current paper cover short-term treatment (one or two injections). In one experiment in which mice were treated for 10 days, it normalized the densities of dendritic spines in the hippocampus, synaptic structures that are overabundant in the absence of FMRP in the mouse model and in humans with FXS.

Postdoctoral fellow Anwesha Banerjee, PhD, conducted experiments in Bassell’s lab. Other contributors include postdoctoral fellow Durgesh Tiwari, PhD, graduate student Angela White at Cincinnati Children’s, and Eric Klann, PhD at New York University.

The test for cognitive flexibility in mice in Gourley’s lab, in which the mice adapt to changed incentives for obtaining food, is described here. Another example of GSK6A’s effects on mouse behavior is seen in a test of social interaction. Given a choice between spending time in a chamber with an unfamiliar mouse or in another chamber with an object, normal mice will prefer a living companion. Mice lacking FMRP show no preference, but treating them with GSK6A one hour before the test increases their social preference. The drug actually blunts social preferences in normal mice.

“It is likely that PI3 kinase – in its various forms — needs to be kept in a tight balance at the synapse,” Bassell says. “Too much or too little can tip things into a suboptimal zone, especially for complex behaviors. We think targeting the excess p110β in FXS can restore signaling between upstream and downstream defects linked to the absence of FMRP.”

While PI3 kinase is an important cellular enzyme, Bassell emphasizes that p110β is just one of its four forms. The researchers showed that GSK6A is selective for p110β only, which indicates that it is less likely to be toxic; more investigation of potential toxicity is necessary.

The paper also includes tests on other biochemical measures such as regulation of protein synthesis in brain tissue slices, susceptibility to seizures triggered by sound, and behaviors such as grooming and nesting.

With respect to clinical trials, the fragile X community has been disappointed before. Based on encouraging studies in mouse models, drugs targeting mGluR5 glutamate receptors were tested in adolescents and adults. mGluR5 drugs did not show clear benefits; recent re-evaluation suggests the choice of outcome measures, the ages of study participants and drug tolerance may have played a role.

“We can’t use mouse behavioral tests alone to understand a drug’s effects,” Bassell says. “It is critical to have molecular, cellular and neurophysiological phenotypes, which we and others do.” He adds that models incorporating human neurons, derived from induced pluripotent stem cells, could be complementary.

Tagged with:

About author

Related Articles