Calorie restriction may promote brain longevity

New York: Restricting calorie intake may prevent Alzheimer’s Disease by triggering activity in the brain associated with longevity, a study by the Mount Sinai School of Medicine suggests.

The study, published in the July 2006 issue of the Journal of Biological Chemistry, is the first to show that restricting caloric intake, specifically carbohydrates, may prevent Alzheimer’s.

Giulio Maria Pasinetti MD, PhD, Professor of Psychiatry and Nuroscience, Director of the Neuroinflammation Research Center at the school says that lifestyle factors such as diet may be crucial to managing the diease.

She said: “This research, however, is the first to show a connection between nutrition and Alzheimer’s Disease neuropathy by defining mechanistic pathways in the brain and scrutinizing biochemical functions. We hope these findings further unlock the mystery of Alzheimer’s and bring hope to the millions of Americans suffering from this disease.”

Alzheimer’s is one of the most feared diseases of ageing and there are currently no cures. Although genetics are thought to be responsible for early onset, this is not the case in the most common form in later life.

People with Alzheimer’s have high levels of beta-amyloid peptides that cause plaque buildup in the brain – though this cannot be seen until after death. Beta-amyloid peptides activate SIRT1, a member of a broad family of proteins known as sirtuins which influence a variety of functions including metabolism and aging.

In the Mount Sinai study it was found that mice were subjected to dietary calorie restriction, based on low carbohydrates food, had reduced beta-amyloid peptides in the brain. Whilst a high caloric intake based on saturated fat was shown to increase levels of beta-amyloid peptides.

It is the first study to show that calorie restriction can promote SIRTI, a molecule associated with brain longevity, and may activate alpha-secretase which can prevent plaque build-up in the brain. study finds that a high caloric intake based on saturated fat promotes AD type beta-amyloidosis, while caloric restriction based on reduced carbohydrate intake is able to prevent it.

Among lifestyle factors influencing AD, recent studies strongly support the evidence that caloric intake may play a role in the relative risk for AD clinical dementia. Most importantly, as mechanistic pathways are defined and their biochemical functions scrutinized, the evidence supporting a direct link between nutrition and AD neuropathology continues to grow.