Alzheimer’s disease is thought to be partially related to a genetic dysfunction that interferes with the brain’s assimilation of glucose.
Diet, exercise, sleep: what if all these criteria were risk factors for Alzheimer’s disease? The influence of our lifestyle and diet on the risk of dementia is the subject of several studies. In the journal Alzheimer’s & Dementia, researchers argue that lifestyle can lead to a defect in the assimilation of glucose by brain cells.
An analysis at the cellular level
To reach this conclusion, researchers from Brigham Young University in Utah analyzed RNA sequences from the brains of 240 patients who had died of Alzheimer’s disease. They studied the gene expression of cells in the nervous system during two types of metabolism: glucose and ketones. The former corresponds to the breakdown of carbohydrates to produce energy and the latter also corresponds to energy production but when insulin levels are low and we burn more fat. This is how the ketogenic diet came about: rich in fats and poor in carbohydrates, and is supposed to help us lose weight.
An inability to use glucose
Genetic analyses of the brains of these Alzheimer’s patients showed that ketones use is not disrupted by the disease. On the other hand, the researchers found a disruption in the metabolism of glucose. “This finding is important because the brain is like a hybrid machine, it has the ability to find its energy in either glucose or ketones, but in the Alzheimer’s-affected brains we observed, there seems to be an underlying genetic impairment in the brain’s ability to use glucose,” the researchers concluded. Benjamin Bikman, professor of physiology and lead author of the study, compared this phenomenon to a photograph: “The body is swimming in a sea of glucose, but the brain is unable to use it.” According to him, it may even get worse because the brain is increasingly dependent on ketones, but our diet is usually high in glucose. One of his theories is that a ketone treatment could help brain function and slow down cognitive decline. This is not the first study to look at the role of glucose in Alzheimer’s disease, but it is the first to identify this phenomenon at the cellular level. Benjamin Bikman points out that the disease is now often thought to be a result of insulin resistance in the brain.
What is Alzheimer’s disease?
Alzheimer’s disease is related to the accumulation of amyloid plaques in the brain, which causes neuronal degeneration. It leads to memory and executive dysfunction, problems with temporal and spatial orientation, and sometimes even speech disorders. It is estimated that 5.8 million Americans of all ages were living with Alzheimer’s disease in 2020.