Obesity + aging linked to Alzheimer's markers in the brain

A new study suggests that when a high-fat, high-sugar diet that leads to obesity is paired with normal aging, it may contribute to the development of Alzheimer's disease. In addition, researchers discovered that certain areas of the brain respond differently to risk factors associated with Alzheimer's. The study is published in Physiological Reports.

Alzheimer's disease, the most common form of dementia, is a progressive disorder that leads to loss of cognitive skills and memory and causes significant changes in behavior. Aging is a significant risk factor for Alzheimer's. Previous studies suggest that diet-related obesity is also associated with development of the disease.

Researchers from Brock University in Ontario, Canada, looked at the effects of an obesity-inducing diet on insulin signaling (the process that tells the body how to use sugar), and markers of inflammation and cellular stress. These factors have been found to be involved in the progression of Alzheimer's disease during the aging process in mice. One group of mice received a high-fat, high-sugar diet ("HFS"), while the ate a normal diet. The researchers measured the animals' inflammation and stress levels in the hippocampus and the prefrontal cortex in the brain after 13 weeks on the assigned diets. They compared the brains of aged mice to those of a younger set of baseline mice. The hippocampus is near the center of the brain and is responsible for long-term memory. The prefrontal cortex, at the front of the brain, oversees complex cognitive, emotional and behavioral function.

Compared to the control group, the HFS group had significantly higher markers of inflammation, (altered insulin signaling) and cellular stress in areas of the hippocampus thought to be involved in the progression of Alzheimer's disease. The prefrontal cortex region of the HFS group showed more signs of insulin resistance, but inflammation and markers did not change. The "region specific differences between the prefrontal cortex and hippocampus in response to aging with a HFS diet [indicates] that the disease pathology is not uniform throughout the brain," the researchers wrote.

The control group's levels were also increased after the trial when compared to the baseline readings. These results supports the theory that aging alone plays a role in the progression of Alzheimer's disease, and obesity exacerbates the effects of aging on brain function.

"This study provides novel information in relation to the mechanistic link between obesity and the transition from adulthood to middle age and signaling cascades that may be related to [Alzheimer's] pathology later in life," the research team wrote. "These results add to our basic understanding of the pathways involved in the early progression of [Alzheimer's] pathogenesis and demonstrate the negative effects of a HFS on both the and hippocampal regions."


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More information: Bradley J. Baranowski et al, Evaluation of neuropathological effects of a high-fat high-sucrose diet in middle-aged male C57BL6/J mice, Physiological Reports (2018). DOI: 10.14814/phy2.13729
Citation: Obesity + aging linked to Alzheimer's markers in the brain (2018, June 28) retrieved 16 October 2019 from https://medicalxpress.com/news/2018-06-obesity-aging-linked-alzheimer-markers.html
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Jun 29, 2018
1 Misleading headline omits important word "rat" and conflates "obesity-inducing" diet with "obesity" Poor journalism
2 For HSF read Apples + Oranges. Now what did my high school chemistry teacher say about not mixing them?
3 Say I knew nothing about automobiles and was given two liquids - Diesel and Petrol. How to work out the best fuel? My first (or second) move wouldn't be to mix them 50/50
Unless someone was paying me to promote, say, Diesel or to run my car if I promoted Diesel or I couldn't face telling family, friends and colleagues I had been wrong about the comparative benefits of Diesel and Petrol. Or all of the above
Back to Sugar + Fat + Alzheimers - since none of the above apply to me, and being a retired English Lit teacher, I turn to a respected scientific journal to help me understand the latest, critical, nutritional research to help me choose the best kinds and combinations of food I should burn to avoid dementia - no help here then
And why?
Bad science kills

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