Tuesday, June 22, 2010

Can Diet Reverse Alzheimers?

Hope springs eternal, except when you're dead. (With no Arrow of Time is one eternally dead or eternally alive? Or am I in a box and if God happens to look inside will my fate then be decided? God, don't look!) On the internet there is a cure and conspiracy for everything. Such is the nature of human cognition, a ramshackle attack on reality that through brute force manages to get enough things right amidst the a multitude of errors and disasters. I read Camus in another life and I really must try to start forgetting him.
If the only significant history of human thought were to be written, it would have to be the history of its successive regrets and its impotences.
The Myth of Sisyphus, page 24
I seriously doubt there can ever be a cure of Alzheimers. (At the end of this post though I do suggest one idea that is worthy of serious consideration.) By the time diagnosis is made the damage tends to be extensive. Take Parkinsons Disease as an example, the individual can lose up to 60% of the neurons in the substantia nigra before symptoms arise. In dementias generally, by time of diagnosis a vicious physiological cycle of destruction has become established and at present there is no obvious solution to that problem. There is an increasingly detailed understanding of these processes and in time it will be possible for individuals to institute strategies that can seriously arrest the progression of even advanced dementia; though at that stage of dementia I'd rather take a bullet than pills. Such treatment expectations however are for another generation.

In our time, studies like this point to strategies that *may* help us. All things considered, it will not be a matter of single strategies or golden elixirs, but rather a lifestyle that incorporates a variety of strategies to minimise the risk of dementia.

What caught my interest in that study is the following:
Pratico said that the cognitive impairment that had been observed in the mice after three months on the methionine-rich diet was completely reversed after two months on the healthier diet, and they were now able to function normally.
"We believe this finding shows that, even if you suffer from the early effects of MCI or Alzheimer's, switching to a healthier diet that is lower in methionine could be helpful in that memory capacity could be improved," he said.
In a prior post on SAMe, a popular "natural" anti-depressant, I referenced various studies which indicated that a high methionine diet could be a risk factor for a variety of conditions, ranging from cancer to cardiovascular disease. One study even suggests a relationship between schizophrenia and high SAMe levels, which is yet another great mystery about schizophrenia. As I noted in that post, and as many studies now indicate, high methionine loading can be very dangerous. The key factor here is Folate and B group vitamins. Without these particular nutrients the high methionine diet can induce high levels of homocysteine. This amino acid is associated with a whole host of pathologies. Causative? Seems to be the case, elevated homocysteine levels clearly is a marker that should be taken seriously. In fact, the title of the study from which the news article arose is:
Normalization of hyperhomocysteinemia improves cognitive deficits and ameliorates brain amyloidosis of a transgenic mouse model of Alzheimer’s disease
Abstract available here. 

There are many studies looking at the relationship between B group vitamins and depression. Results are inconclusive and I suggest one significant confounder here is the balance of methionine intake relative to folate, B6, and B12. With that in mind, and for those who take health seriously, it is worth giving serious consideration to having your homocysteine levels checked. 

In the news article one of the study authors asserts:

"What it tells us is that the brain has this plasticity to reverse a lot of the bad things that have occurred; the ability to recoup a lot of things such as memory that were apparently lost, but obviously not totally lost," he said.In the news article one of the study authors asserts:
How much we have learned over the last decade. Modern biomedical research is a wonder but remains very much a science in becoming. No new cells in the CNS? Get outta here, there are now recognised 3 major areas for neurogenesis in the adult brain: the dentate gyrus, the sub-ventricular zone, and the olfactory bulb. There is a constant stream of new brain cells being made available. There must be some degree of regenerative capacity because studies on depression reveal that once depression is effectively treated the cerebral atrophy recedes, sometimes completely.

Alzheimers though, and dementias in general, involve a type of damage that spreads and and is self-perpetuating. Many years ago I read a striking study by Tracy McIntosh that touched on this. After repeated mild brain injury one could see the amyloid deposition slowly spreading out from the point of impact. Not a pretty picture but there remains hope because recent studies are now indicating that not only is amyloid removal possible but can be enhanced through various strategies. Just last night I forwarded to a friend a study indicating that another key marker of aging, lipofuscin, which arises from failure of degradation processes and like amyloid was once thought impossible to eliminate, can actually be eliminated from neurons, probably to be released into the bloodstream. Lipofuscin is a key cell marker for cell aging, the one constant in cell aging. If you would like to learn more about lipofuscin then read this earlier post. And this one.

Poor Mr. Camus, he never got to see the great wonders of modern science, the power of endless research and thinking, the promise of gifted individuals devoting their lives to tackling some of the greatest challenges we can face.

Can Diet reverse Alzheimers? Possibly, but only at the margins. The problem with dementias, like so many age related conditions, is that these pathologies are a slow train coming but when they hit you they will still kill you. You have to get off the track of doom. The problem is that no matter how careful we are with diet and lifestyle there are no guarantees. There is, however, one method that could prove invaluable. A friend of mine, a gifted neuropsychologist, once made an excellent suggestion. He said that everyone should have a set of neuropsychology tests to establish baseline values from which future performance could be measured. That way each of us could have some solid quantifiers that in the years to come could presage the onset of dementias. When the performance starts to decline, and given regular testing it will be much easier to see real world changes in the trend, it is time to get thee to thy physician and start demanding various tests. That way, if a problem is identified, we can act and hopefully before it is too late. 

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