Brief Reduction in Dietary Fat Improves Cognitive Dysfunction in Mice with Obesity and Type II Diabetes
OHSU researchers, led by Jacob Raber, Ph.D., have discovered that the cognitive dysfunction that that often results from obesity and type II diabetes can be treated. The study reveals that even a brief reduction in dietary fat content in mice that are fed a high-fat diet for a substantial period of time led to a complete rescue of cognitive function.
Their findings, based on a mouse model, were published in the journal EBioMedicine.
After five months of subsisting on a high-fat diet, mice in this study developed multiple cognitive impairments, including deficits in novel object recognition, in cued fear memory and in spatial learning and memory. However, after giving the obese mice a low fat diet for an additional month, the researchers saw improvements in metabolism, and notably a full reversal in some of the cognitive problems and insulin signaling that they had developed.
Additionally, for the first time, researchers infused obese mice that had type II diabetes and cognitive impairments with “healthy” plasma from age-matched, low fat diet-fed mice to determine whether it would improve their cognitive abilities. Remarkably, infusions of “healthy” plasma were found to improve memory in obese mice that were fed a high fat diet, in spite of their continued consumption of high fat food.
With society facing twin tidal waves of an aging population at risk of developing Alzheimer’s disease and rising obesity rates – both of which are also risk factors for cognitive impairment and Alzheimer’s disease, this research casts new light on how certain cognitive impairments can be reversed.
To build on this foundation, researchers will next look at mice with genetic risk factors to develop age-related cognitive decline and Alzheimer’s disease.