There is a decades long debate about the role of inflammation in Alzheimer’s disease. The proteins known as plaques and tangles are the hallmarks of the disease, but recent evidence supports earlier suspicions that an inflammatory response in the brain may be partly responsible for Alzheimer’s. So, is Alzheimer’s an autoimmune disease?
The immune system and inflammation
So what exactly is inflammation? Normally our immune system reacts to invaders in the body; white blood cells attack a wide variety of pathogens including parasites and viruses and protect us from disease. Sometimes our immune system becomes over-active and produces antibodies that attack healthy tissue. Rheumatoid arthritis is an example of such an autoimmune disease, one in which the immune system creates antibodies that attack joints. Other autoimmune diseases include Type 1 diabetes (antibodies attack insulin-producing cells in the pancreas) and multiple sclerosis (immune system attacks nerve cells). The treatments for inflammation generally concentrate on reducing immune system activity, often with limited success.
Is Alzheimer’s an autoimmune disease?
Some scientists have recently begun to consider the possibility that Alzheimer’s disease is, in fact, an autoimmune disease. The Amyloid plaques and neurofibrillary tangles associated with Alzheimer’s are present to some degree even in healthy brains, and likely perform necessary functions. Our immune system produces antibodies to rid the brain of the plaques when they degrade and become harmful. They also clear the brain of neurons destroyed by the tangles . These researchers suspect that an overproduction of these antibodies may be responsible for the onset of Alzheimer’s, and may hasten the disease process. In the article A New Look at Brain Inflammation in Alzheimer’s, Jim Schnabel notes:
Wherever it occurs in the body, chronic inflammation is a double-edged sword. The initial inflammatory response is meant to defend tissues against molecular foes such as viruses, cancerous cells, and harmful amyloid protein aggregates. But the longer it lasts, the more this inflammation stresses and kills healthy, “innocent bystander” cells. Over time—as in rheumatoid arthritis, for example—the inflammation can become self-sustaining.
Mr. Schnabel goes on to say that this out-of-control process that causes rheumatoid arthritis is also conspicuous in Alzheimer’s disease. Instead of just clearing the brain of amyloid plaques the antibodies begin to attack healthy brain cells.
Inflammation and Alzheimer’s disease
A paper presented at the 2014 Alzheimer’s Association International Conference suggests that the drug etanercept might halt the progression of Alzheimer’s disease. This reinforces the possible connection that Schnabel alluded to (above). Etanercept (trade name Enbrel) is a type of anti-inflammatory drug used to treat rheumatoid arthritis.
Clive Holmes of the University of Southampton, UK, presented the results of the study which tested 15 people with mild to moderate Alzheimer’s who were given the drug etanercept against a control group that received a placebo (saltwater). Holmes’s team found that the participants taking etanercept performed comparatively better on memory, behavior and well-being when compared to the control group. There was no statistically significant difference in their performance on other tests of cognition. Researches warn against getting too excited before larger trials have been conducted, but the results, if not promising, are at least encouraging.
We should also warn against the use of etanercept (brand name Enbrel) and other anti-inflammatory medications without the strictest medical supervision. These drugs are designed to suppress the immune system and their use can lead to serious infections. If you are using etanercept do not discontinue use without consulting your doctor. Natural anti-inflammatory substances like turmeric, ginger, cayenne and other chilies, and green tea can sometimes be as effective as prescribed medication without the potentially dangerous side effects.
In another study, a group of researchers led by Richard Chou reviewed a medical database and identified more than forty-two thousand people with rheumatoid arthritis. From this group they pulled 165 people with newly diagnosed Alzheimer’s disease and compared those to a control group. They found that people who were undergoing anti-TNF therapies were significantly less likely to develop Alzheimer’s disease. Anti-TNF (anti-tumor necrosis factor) drugs including etanercept are commonly used to combat autoimmune diseases like rheumatoid arthritis.
“In this study, the incidence of Alzheimer’s disease was found to be lower in patients with rheumatoid arthritis who had been treated with anti-TNF agents,” says Dr. Richard Chou, MD, PhD; assistant professor at Dartmouth Medical School and lead investigator in the study. “Although the cause of Alzheimer’s disease is not known, the results suggest that TNF may play a role in its development.”
The good news is that if Alzheimer’s is, in fact, an autoimmune disorder, we understand the disease better, and that may lead to better treatment options. On the other hand, medical science does not have a very impressive track record with other autoimmune diseases including MS, rheumatoid arthritis, and lupus. Hopefully preventative measures will eventually make the need for a cure less urgent. Whether or not you are worried about dementia, a diet rich in anti-inflammatory foods is a good idea.
Turmeric is one of the strongest anti inflammatory foods available, but there are others. The list below includes some that, if they don’t already have a place at your dinner table, you should consider adding to your diet.
- Wild Salmon and other Fatty Cold Water Fish– don’t substitute the farm raised variety, which could potentially cause more harm than good
- Shiitake Mushrooms and other oriental mushrooms
- Green Tea
- Garlic and Onion
- Paypa – also improves digestion. Get organic whenever possible
- Blueberries and Other Berries – who doesn’t like berries?
- Extra Virgin Olive Oil – because of the extraction process, pure olive oil, or other olive oils that aren’t labeled “extra virgin” are not nearly as effective
- Broccoli and Cauliflower
- Sweet Potato
- Dark Leafy Greens – spinach, kale, collard greens, etc
- Whole Grains
- Peppers and Tomatoes – both members of the nightshade family; some people think nightshade might worsen the inflammatory symptoms of rheumatoid arthritis, so use cautiously
This article is provided for general information only, without taking into account any person’s condition, situation or needs. It is not intended as a substitute for professional medical advice, diagnosis, treatment or other advice.
More Research about “Is Alzheimer’s an Autoimmune Disease?”
- Arthritis drug shows potential to stall Alzheimer’s; New Scientist, 16 July 2014 by Andy Coghlan
- A New Look at Brain Inflammation in Alzheimer’s; Jim Schnabel; January 16, 2013
- Anti-TNF Therapies for rheumatoid arthritis could reduce Alzheimer’s risk (Press Release): Dr. Richard Chou, MD, PhD; The journal of the American College of Rheumatology