Neuroscientists find promise in addressing Fragile X afflictions

September 19, 2012

Neuroscientists at New York University have devised a method that has reduced several afflictions associated with Fragile X syndrome (FXS) in laboratory mice. Their findings, which are reported in the journal Neuron, offer new possibilities for addressing FXS, the leading inherited cause of autism and intellectual disability.

Those afflicted with FXS do not possess the protein FMRP, which is a suppressor of . Absent this suppressor, protein synthesis is exaggerated, producing a range of mental and physical disorders.

Previous research has indirectly targeted protein synthesis by seeking to temper, but not block, this process. The NYU researchers, by contrast, sought a more fundamental intervention—removing the enzyme, p70 ribosomal S6 kinase 1, or S6K1, which has previously been shown to regulate protein synthesis in FXS mice. By addressing this phenomenon at the molecular level, they hoped to diminish many of the conditions associated with FXS.

To determine the impact of this intervention, the researchers compared the behaviors of these FXS mice with those normal mice while also observing the of these same FXS mice.

Their results showed that protein synthesis in the FXS mice lacking S6K1 became similar to that of normal mice. Moreover, through a series of experiments and other measurements (e.g., navigating a maze, interacting with other mice), they found both physical and behavioral improvements in the FXS mice:

  • The FXS mice missing the S6K1 enzyme showed greater ability than other FXS mice to adjust their behaviors when facing conditions that were similar, but not identical, to previous experiences. This attribute, , is typically diminished is those afflicted with FXS. In this experiment, the FXS mice missing the S6K1 enzyme were more successful than other FXS mice to navigate a maze that was similar to a maze they had previously mastered.
  • The FXS mice missing the S6K1 enzyme showed enhanced social behaviors, which are measured through a commonly used "social novelty test." Under this method, mice interact with each other multiple times to gauge familiarity. In this experiment, the FXS mice missing the S6K1 enzyme showed greater familiarity with mice they previously encountered than did other FXS mice. Humans afflicted with FXS have diminished abilities for social interaction.
  • The FXS mice missing the S6K1 enzyme showed a correction in three physical traits often associated with this condition: immature dendritic spine morphology, which indicates abnormal connections between neurons, excessive weight gain, and macro-orchidism, or enlarged testicles.
However, the researchers did not find uniform improvements in the tested FXS mice—they still engaged in excessive repetitive behaviors (i.e., repeatedly burying marbles in an experiment), a common trait among those afflicted with FXS.

Nonetheless, the research team said the findings showed remarkable promise.

"We think these results set the stage for a viable pharmacological approach to target S6K1, with the aim of diminishing or even reversing the afflictions associated with ," said Eric Klann, a professor in NYU's Center for Neural Science and the study's senior author.

Explore further: Fragile X syndrome can be reversed in adult mouse brain

Related Stories

Fragile X syndrome can be reversed in adult mouse brain

April 11, 2012
A recent study finds that a new compound reverses many of the major symptoms associated with Fragile X syndrome (FXS), the most common form of inherited intellectual disability and a leading cause of autism. The paper, published ...

Most common form of inherited intellectual disability may be treatable

May 17, 2011
Advancements over the last 10 years in understanding intellectual disability (ID, formerly mental retardation), have led to the once-unimaginable possibility that ID may be treatable, a review of more than 100 studies on ...

Recommended for you

Exosomes are the missing link to insulin resistance in diabetes

September 21, 2017
Chronic tissue inflammation resulting from obesity is an underlying cause of insulin resistance and type 2 diabetes. But the mechanism by which this occurs has remained cloaked, until now.

Thousands of new microbial communities identified in human body

September 20, 2017
A new study of the human microbiome—the trillions of microbial organisms that live on and within our bodies—has analyzed thousands of new measurements of microbial communities from the gut, skin, mouth, and vaginal microbiome, ...

Study finds immune system is critical to regeneration

September 20, 2017
The answer to regenerative medicine's most compelling question—why some organisms can regenerate major body parts such as hearts and limbs while others, such as humans, cannot—may lie with the body's innate immune system, ...

Immune cells produce wound healing factor, could lead to new IBD treatment

September 20, 2017
Specific immune cells have the ability to produce a healing factor that can promote wound repair in the intestine, a finding that could lead to new, potential therapeutic treatments for inflammatory bowel disease (IBD), according ...

As men's weight rises, sperm health may fall

September 20, 2017
(HealthDay)—A widening waistline may make for shrinking numbers of sperm, new research suggests.

New model may help science overcome the brain's fortress-like barrier

September 19, 2017
Scientists have helped provide a way to better understand how to enable drugs to enter the brain and how cancer cells make it past the blood brain barrier.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.