A study published in Metabolic Brain Disease has established a clear link between mice being fed a high-fat diet for 30 weeks, resulting in diabetes, and a subsequent worsening of their cognitive abilities. This included developing anxiety, depression and worsening Alzheimer’s disease.
Mice with impaired cognitive function were also more likely to gain excessive weight due to poor metabolism caused by brain changes.
Neuroscientist and biochemist Associate Professor Larisa Bobrovskaya, who co-led the study said that the research adds to the growing body of evidence linking chronic obesity and diabetes with Alzheimer’s disease.
“Obesity and diabetes impair the central nervous system, exacerbating psychiatric disorders and cognitive decline. We demonstrated this in our study with mice,” said Associate Prof Bobrovskaya.
In the study, mice were randomised to a standard diet or a high-fat diet for 30 weeks, starting at eight weeks of age. Food intake, body weight and glucose levels were monitored at different intervals, along with glucose and insulin tolerance tests and cognitive dysfunction.
The mice on the high-fat diet gained significant weight, developed insulin resistance and started behaving abnormally compared to those fed a standard diet.
Genetically modified Alzheimer’s disease mice showed a significant deterioration of cognition and pathological changes in the brain while fed the high fat diet.
“Obese individuals have about a 55 per cent increased risk of developing depression, and diabetes will double that risk,” Assoc Prof Bobrovskaya said.
“Our findings underline the importance of addressing the global obesity epidemic. A combination of obesity, age and diabetes is very likely to lead to a decline in cognitive abilities, Alzheimer’s disease and other mental health disorders.”
Source: University of South Australia
