Neurological researchers find fat may be linked to memory loss

October 9, 2013, Rush University Medical Center

Although problems with memory become increasingly common as people age, in some persons, memories last long time, even a life time. On the other hand, some people experience milder to substantial memory problems even at an earlier age.

Although there are several risk factors of dementia, abnormal fat metabolism has been known to pose a risk for memory and learning. People with high amounts of in their middle age are 3.6 times as likely to develop and dementia later in their life.

Neurological scientists at the Rush University Medical Center in collaboration with the National Institutes of Health have discovered that the same protein that controls fat metabolism in the liver resides in the memory center of the (hippocampus) and controls memory and learning.

Results from the study funded by the Alzheimer's Association and the National Institutes of Health were recently published in Cell Reports.

"We need to better understand how fat is connected to memory and learning so that we can develop effective approach to protect memory and learning," said Kalipada Pahan, PhD, the Floyd A. Davis professor of neurology at Rush University Medical Center.

The liver is the body's major fat metabolizing organ. Peroxisome proliferator-activated receptor alpha (PPARalpha) is known to control fat metabolism in the liver. Accordingly, PPARalpha is highly expressed in the liver.

"We are surprised to find high level of PPARalpha in the hippocampus of animal models," said Pahan.

"While PPARalpha deficient mice are poor in learning and memory, injection of PPAR? to the hippocampus of PPARalpha deficient mice improves learning and memory", said Pahan.

Since PPARalpha directly controls , people with abdominal fat levels have depleted PPARalpha in the liver and abnormal lipid metabolism. At first, these individuals lose PPARalpha from the liver and then eventually from the whole body including the brain. Therefore, abdominal fat is an early indication of some kind of dementia later in life, according to Pahan.

By bone marrow chimera technique, researchers were able to create some mice having normal PPARalpha in the liver and depleted PPARalpha in the brain. These mice were poor in memory and learning. On the other hand, mice that have normal PPARalpha in the brain and depleted PPARalpha in the showed normal memory.

"Our study indicates that people may suffer from memory-related problems only when they lose PPARalpha in the ", said Pahan.

CREB (cyclic AMP response element-binding protein) is called the master regulator of memory as it controls different memory-related proteins. "Our study shows that PPARalpha directly stimulates CREB and thereby increases memory-related proteins", said Pahan.

"Further research must be conducted to see how we could potentially maintain normal PPARalpha in the brain in order to be resistant to memory loss", said Pahan.

Other Rush researchers involved in this study include Avik Roy, PhD, research assistant professor; Malabendu Jana, PhD assistant professor; Grant Corbett, neuroscience graduate student; Shilpa Ramaswamy, instructor; and Jeffrey H. Kordower, PhD, the Jean Schweppe Armour professor of neurological sciences.

Alzheimer's disease is the most common human disorder associated with memory loss. This disease slowly destroys and thinking skills, and eventually even the ability to carry out the simplest tasks. Nationwide, the total payments for services for people with Alzheimer's and other forms of dementia will total $203 billion in 2013. By 2050, the total costs are expected to increase 500 percent to a staggering $1.2 trillion.

Explore further: Scientists identify Buphenyl as a possible drug for Alzheimer's disease

Related Stories

Scientists identify Buphenyl as a possible drug for Alzheimer's disease

March 11, 2013
(Medical Xpress)—Buphenyl, an FDA-approved medication for hyperammonemia, may protect memory and prevent the progression of Alzheimer's disease. Hyperammonemia is a life-threatening condition that can affect patients at ...

Adolescents' high-fat diet impairs memory and learning

June 17, 2013
A high-fat diet in adolescence appears to have long-lasting effects on learning and memory during adulthood, a new study in mice finds. The results were presented Saturday at The Endocrine Society's 95th Annual Meeting in ...

Sudden decline in testosterone may cause Parkinson's disease symptoms in men

July 27, 2013
The results of a new study by neurological researchers at Rush University Medical Center show that a sudden decrease of testosterone, the male sex hormone, may cause Parkinson's like symptoms in male mice. The findings were ...

Memory decline may be earliest sign of dementia

July 17, 2013
(AP)—Memory problems that are often dismissed as a normal part of aging may not be so harmless after all.

Study helps deconstruct estrogen's role in memory

September 18, 2013
The loss of estrogens at menopause increases a woman's risk of dementia and Alzheimer's disease, yet hormone replacement therapy can cause harmful side effects.

Long-term memory in the cortex

August 27, 2013
(Medical Xpress)—'Where' and 'how' memories are encoded in a nervous system is one of the most challenging questions in biological research. The formation and recall of associative memories is essential for an independent ...

Recommended for you

Research reveals atomic-level changes in ALS-linked protein

January 18, 2018
For the first time, researchers have described atom-by-atom changes in a family of proteins linked to amyotrophic lateral sclerosis (ALS), a group of brain disorders known as frontotemporal dementia and degenerative diseases ...

Fragile X finding shows normal neurons that interact poorly

January 18, 2018
Neurons in mice afflicted with the genetic defect that causes Fragile X syndrome (FXS) appear similar to those in healthy mice, but these neurons fail to interact normally, resulting in the long-known cognitive impairments, ...

How your brain remembers what you had for dinner last night

January 17, 2018
Confirming earlier computational models, researchers at University of California San Diego and UC San Diego School of Medicine, with colleagues in Arizona and Louisiana, report that episodic memories are encoded in the hippocampus ...

Recording a thought's fleeting trip through the brain

January 17, 2018
University of California, Berkeley neuroscientists have tracked the progress of a thought through the brain, showing clearly how the prefrontal cortex at the front of the brain coordinates activity to help us act in response ...

Midbrain 'start neurons' control whether we walk or run

January 17, 2018
Locomotion comprises the most fundamental movements we perform. It is a complex sequence from initiating the first step, to stopping when we reach our goal. At the same time, locomotion is executed at different speeds to ...

Neuroscientists suggest a model for how we gain volitional control of what we hold in our minds

January 16, 2018
Working memory is a sort of "mental sketchpad" that allows you to accomplish everyday tasks such as calling in your hungry family's takeout order and finding the bathroom you were just told "will be the third door on the ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.