Neurons like it tidy. Brain cells called glia help neurons perform at their best by cleaning up toxic cellular debris. But a diet high in sugar makes glia insulin resistant — which turns them into apathetic housekeepers that let damaging debris pile up, according to new work from Fred Hutchinson Cancer Center scientists, published in the journal PLOS Biology. The findings in fruit flies could help explain how diet influences risk of neurodegenerative disorders like Alzheimer’s disease.
“These findings show how eating processed food doesn’t just affect weight gain, it affects cognitive function. It affects a deep functioning of your body,” said Fred Hutch obesity researcher and senior author Akhila Rajan, PhD. “Our study provided missing evidence that glial insulin resistance has consequences to glia’s debris-clearing role.”
In the new work, Rajan Lab postdoctoral fellow Mroj Alassaf, PhD, confirmed that, like peripheral tissues, brain cells can become insulin resistant. Alassaf demonstrated that the high levels of insulin induced by excess dietary sugar causes glial dysfunction, which prevents glial cells from cleaning up damaging cellular debris.
