A small study of boys and men with autism reports that a compound derived from broccoli can alleviate some of their symptoms (Proc. Natl. Acad. Sci. USA 2014, DOI: 10.1073/pnas.1416940111).
The collection of behavioral and intellectual symptoms known as autism—including social and communication difficulties and repetitive behaviors—likely has myriad causes, largely genetic.
To alleviate the symptoms associated with autism, researchers are studying a handful of potentially therapeutic molecules, including certain probiotics and the diuretic blood pressure medication bumetanide.
But this work is still in its infancy, says Michael Ehlers, chief scientific officer for neuroscience at Pfizer Neuroscience in Cambridge, Mass. “Despite a real advance in the complex genetics of autism spectrum disorders, we still have very little by way of rational strategies for therapeutic intervention by novel medicines,” he says.
Andrew W. Zimmerman, a pediatric neurologist at the Lurie Center for Autism at Massachusetts General Hospital for Children; Paul Talalay of Johns Hopkins University School of Medicine; and their colleagues have now discovered another possible therapeutic angle in the compound sulforaphane. This molecule is an isothiocyanate, the precursor of which, glucoraphanin, is found in high concentrations in broccoli sprouts.
Sulforaphane protects cells against numerous biochemical threats, including oxidative stress and mitochondrial dysfunction. These biochemical abnormalities have also been associated with autism symptoms.
In addition, Zimmerman previously showed that in at least 30% of people with autism, symptoms appear to lessen temporarily when they have a fever. Both fevers and sulforaphane stimulate the production of heat shock proteins involved in the cellular stress response.
These lines of evidence, along with the inherent harmlessness of sulforaphane, prompted the authors to conduct a study in which they gave 29 males, ages 13 to 27, with moderate to severe autism a standardized dose of sulforaphane for 18 weeks.
The group found improvement in several symptoms, including social interaction and verbal communication, compared with a control group. Tellingly, they also found that these improvements waned once the subjects stopped taking sulforaphane.
Pfizer’s Ehlers, who says he finds the work intriguing, says larger studies are needed. “If replicated in larger cohorts, these results may point toward drugs targeting oxidative stress, mitochondrial dysfunction, and inflammatory processes for autism,” he says.