Brain scientists suggest new reason for controlling blood sugar levels: This may help reduce the risk of developing Alzheimer's disease.
"There are many reasons for you to take [blood sugar] under control," says David Holtzman, chair of neurology at Washington University in St. Louis. "But this is certainly one."
Holtzman moderated a panel Sunday at a meeting of the Neuroscience Society in Chicago that presented new research examining the links between Alzheimer's disease and diabetes.
"The risk of dementia increases about twice in people who have diabetes or the metabolic syndrome (a group of risk factors that often precedes diabetes)," Holtzman says. "But what is not clear is what is the connection?"
One possibility involves the way the brain metabolizes sugar, says Likin Zhao, an assistant professor at the University of Kansas School of Pharmacy.
Zhao wants to know why people whose bodies produce a protein called ApoE2 are less likely to get Alzheimer's.
Previous studies have shown that these people are less likely to develop sticky plaques in the brain associated with the disease. But Zhao looked at how ApoE2 affects glycolysis, part of a process that allows brain cells to convert sugar into energy.
Her research has found that glycolysis helps brain cells communicate with and release from toxins associated with Alzheimer's disease.
Therefore, it administered ApoE2 to mice that develop an Alzheimer's form. And sure enough, Zhao says, the substance not only improves energy production in brain cells, it also makes the cells healthier overall.
"All this together increases the brain's resistance to Alzheimer's disease," she says.
Another scientist describes how mice are fed a diet that includes a lot of fat and sugar and are more likely to develop both diabetes and memory impairment.
The diet causes an increase in dysfunctional brain cells in mice, says Sami Gabudz of the Institute of Biomedicine at the University of Eastern Finland. According to people, this could "exacerbate" the development of Alzheimer's disease.
Sleep problems are another common feature of both Alzheimer's and diabetes, says Shannon Macauley, assistant professor of gerontology and geriatric medicine at the Wake Forest School of Medicine.
She presented studies showing that in mice brain changes associated with Alzheimer's disease interfere with sleep. But abnormal blood sugar levels, both high and low, also "lead to disturbed sleep," she says.
This, in her opinion, is that poor sleep is a known risk factor for Alzheimer's disease. Thus, maintaining normal blood sugar levels in Alzheimer's patients can improve their sleep and even delay the disease, she says.
All these animal studies could ultimately help people, says Holtzman of the University of Washington.
"If we can understand what diabetes is doing to increase the risk, maybe it will lead us to new goals, drug targets or treatment goals," he says