Common statin shows promise for Fragile X treatment
Rodent model shows early dosage reduces cognitive decline. Biplab Das reports.
New research shows that lovastatin, a cholesterol-lowering drug, may help prevent brain damage caused by fragile X syndrome (FXS), a genetic disorder that disrupts the normal activity of nerve cells in specific brain regions that are associated with learning and memory during early stage of development.
In a paper published in the journal Science Translational Medicine, researchers have demonstrated that the drug arrests harmful changes in the hippocampus, the seat of memory in the brain, and the prefrontal cortex, a brain region responsible for planning and decision making, in FXS-afflicted rats.
The treatment not only halted brain damage but also restored the normal activity of nerve cells in the affected parts of the brain, suggesting that such drug intervention could potentially modify neural development in patients with FXS and similar disorders.
In humans, FXS, one of the most common forms of intellectual disability, occurs due to mutations in the FMR1 gene. It affects one in 4000 boys and one in 8000 girls at a very early stage of development.
FMR1 carries the code for making a protein called FMRP. This protein helps regulate the production of other proteins. It also plays a role in the development of synapses, connections between nerve cells, which relay nerve impulses, maintaining the functions of myriad brain circuits.
Previous studies with animals have highlighted that it is possible to alleviate the symptoms of the condition using specific drugs. However, it remains unknown whether a brief, early treatment can be beneficial for FXS patients.
To find out, a research team, led by Peter Kind from the University of Edinburgh in the UK, chose to test the efficacy of lovastatin, a safe and widely used drug.
Kind and his co-researchers from India and the US first conducted several tests of associative memory and learning in a rat model of FXS. To do this, they deleted the Fmr1 gene, the rat counterpart of FMR1. The result was delayed development of associative memory and learning skills.
They found that lovastatin treatment administered between five and nine weeks of age, a critical window for developing associative memory, stopped the emergence of cognitive impairment.
The drug restored the proper development of associative learning in the rats. Benefits lingered for several months even after the end of treatment.
But the researchers are cautious about whether the findings will translate to therapies for individuals with FXS. Since the lovastatin treatment was initiated in one-month-old rats, it is difficult to accurately estimate the corresponding age in humans, they add.