Reducing the intake of advanced glycation endproducts (AGEs), especially in older patients, may help to slow down diabetes and Alzheimer’s epidemics….
Age-associated dementia and Alzheimer’s disease (AD) are currently epidemic. Neither their cause nor connection to the metabolic syndrome (MS) is clear. Suppression of deacetylase survival factor sirtuin 1 (SIRT1), a key host defense, is a central feature of AD. Age-related MS and diabetes are also causally associated with suppressed SIRT1 partly due to oxidant glycotoxins [advanced glycation end products (AGEs)]. Changes in the modern diet include excessive nutrient-bound AGEs, such as neurotoxic methyl-glyoxal derivatives (MG).
To determine whether dietary AGEs promote AD, researchers led by Helen Vlassara at the Icahn School of Medicine at Mount Sinai in New York, evaluated WT mice pair-fed three diets throughout life: low-AGE (MG−), MG-supplemented low-AGE (MG+), and regular (Reg) chow. Older MG+-fed mice, similar to old Reg controls, developed MS, increased brain amyloid-β42, deposits of AGEs, gliosis, and cognitive deficits, accompanied by suppressed SIRT1, nicotinamide phosphoribosyltransferase, AGE receptor 1, and PPARγ. These changes were not due to aging or caloric intake, as neither these changes nor the MS were present in age-matched, pair-fed MG− mice. The mouse data were enhanced by significant temporal correlations between high circulating AGEs and impaired cognition, as well as insulin sensitivity in older humans, in whom dietary and serum MG levels strongly and inversely associated with SIRT1 gene expression. The data identify a specific AGE (MG) as a modifiable risk factor for AD and MS, possibly acting via suppressed SIRT1 and other host defenses, to promote chronic oxidant stress and inflammation. The researchers wrote, "Because SIRT1 deficiency in humans is both preventable and reversible by AGE reduction, a therapeutic strategy that includes AGE reduction may offer a new strategy to combat the epidemics of AD and MS."
In conclusion, this study illustrated that it’s not always about the types of food a person eats that makes them less healthy. In the case of this study, the way the food was prepared played a major factor in the risk of Alzheimer’s disease and diabetes.
The Journal of Neuroscience. March 2014