8th Jan 2019
Common gut infection linked to memory loss and Alzheimer’s
Author: Ben Hocking
Gut infection linked to Alzheimer’s

A fungus previously perceived as harmless can cause memory problems and brain abnormalities that resemble those characteristics of Alzheimer's disease.

Researchers at the Baylor College of Medicine have discovered that the common yeast Candida albicans, a type of fungus that grows naturally in the human gut, mouth, and vagina, can cross the blood-brain barrier and trigger an inflammatory response which results in the formation of granuloma-type structures and temporary mild memory impairments in mice.

The granulomas share features with plaques found in Alzheimer’s disease, supporting future studies on the long-term neurological consequences of sustained Candida albicans infection.

“An increasing number of clinical observations by us and other groups indicates that fungi are becoming a more common cause of upper airway allergic diseases such as asthma, as well as other conditions such as sepsis, a potentially life-threatening disease caused by the body's response to an infection,” said report author Dr David Corry.

Fungal infections causing airway allergic diseases and sepsis have also been associated with increased risk for dementia later, Dr Corry explained.

“These observations led us to investigate the possibility that fungus might produce a brain infection and, if so, the consequences of having that kind of infection,” said Dr Corry.

The researchers began their investigation by developing a mouse model of a low-grade fungus infection with the common yeast Candida albicans that would not cause severe disease but might carry implications for brain function. They tested several doses and finally settled on one dose of 25,000 yeasts.

They injected Candida albicans into the blood stream of mice and were surprised to discover that the yeast can cross the blood-brain barrier, which is usually a robust protective mechanism the brain employs to exclude all kinds of large and small molecules, as well as a number of microorganisms that can potentially damage the brain.

“We thought that yeast would not enter the brain, but it does,” Dr Corry said.

“In the brain, the yeast triggered the activity of microglia, a resident type of immune cell. The cells became very active ‘eating and digesting’ the yeast. They also produced a number of molecules that mediated an inflammatory response leading to the capture of the yeasts inside a granule-type structure inside the brain.”

Dr Corry and his colleagues also tested the animals’ memory in both yeast-infected and non-infected mice. They found that infected mice had impaired spatial memory, which reversed when the infection cleared.

The mice cleared the yeast infection in about 10 days; however, the microglia remained active and the granulomas persisted well past this point, out to at least day 21.

“The results prompted us to consider the possibility that in some cases, fungi also could be involved in the development of chronic neurodegenerative disorders, such as Alzheimer’s, Parkinson’s and multiple sclerosis. We are currently exploring this possibility,” Dr Corry explained.

Have you ever suffered from a yeast infection? Are you worried about these findings?



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    Old Geezer
    9th Jan 2019
    A craving for sweet food is an indication of a yeast problem in your gut. You put a teaspoon of vinegar in a glass of water and it will get rid of the craving.
    9th Jan 2019
    Sources of a yeast allergy may include:
    most breads and some baked goods, such as muffins, biscuits, croissants, or cinnamon rolls.
    cereal products.
    alcohol, especially beer, wine, and ciders.
    premade stocks, stock cubes, and gravies.
    vinegar and foods containing vinegar, such as pickles or salad dressing.
    9th Jan 2019
    I have had a number of skin and gut problems over the years which might be related to a yeast infection, but i'm not sure how it could be treated now, as the yeast has probably done the damage to my brain?
    9th Jan 2019
    I have had a number of skin and gut problems over the years which might be related to a yeast infection, but i'm not sure how it could be treated now, as the yeast has probably done the damage to my brain?
    9th Jan 2019
    Type 2 diabetes has also been linked to Alzheimer’s as well as a number of other conditions.

    How many times do people need to be told to eat a diet high in plant foods, moderate protein and cut the low nutritional value foods such as fast foods, over processed foods high in added sugar.
    Nose Hair Bob
    9th Jan 2019
    Processed foods should be labeled like cigarettes especially sugar/salt full. The obesity and diabetes problem in the US and Aus, Eng etc is now referred to as the 'Western diet'. Plaque or blocked arterial function which Alzheimer's is related to is caused by this diet (processed meat, animal fats,sugar...Diabetes is a relatively new western diet disease which was unheard of in African, Japanese societies until recently...thanks in no small part to Golden Arches etc. No brainer.
    9th Jan 2019
    I have had many thrush outbreaks esp when pregnant and am having issues with memory so am worried by these findings.
    10th Jan 2019
    Feeding your gut with fresh veg and fruit increases the good bacteria, I also recommend lemon juice every morning. Processed packaged foods is what is fueling unbalanced gut bacteria.

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