Preventing Cognitive Decline - A Case For Curcumin
The incidence of neurodegenerative diseases in the Asian subcontinent is much lower than in North America. In India, only 0.7% of people aged 70-79 are affected by Alzheimer’s Disease (AD). In contrast, the prevalence in America is more than quadrupled at 3.1%. The reasons for this are hard to elucidate as there are many different environmental and genetic factors, both known and unknown, which make a person more or less prone to developing Alzheimer’s.
One differential aspect between Western and Eastern societies, which may explain this large difference in Alzheimer’s susceptibility, is diet. Oxidative and inflammatory damage has long been associated with Mild Cognitive Impairment (a precursor to Alzheimer’s) and Alzheimer’s disease. It therefore follows that anti-oxidative and anti-inflammatory substances could help protect against neurodegeneration. This has been shown to be the case.
A particular compound, curcumin, has received increasing experimental and clinical attention for it’s potential therapeutic effects. Curcumin is the major active compound present in Turmeric, which is indigenous to the tropical Indian subcontinent. Turmeric is used in a large variety of foods throughout Southern Asia and the Middle East. It is the primary component in yellow curry.
Alzheimer’s disease involves a central nervous system inflammatory response, and AD risk is reduced in those taking non-steroidal anti-inflammatory drugs (NSAID). Novel anti-inflammatory and anti-oxidative compounds are continually researched as possible therapeutic strategies. What makes curcumin special is that it is not only a potent anti-oxidant and anti-inflammatory agent, but it also interacts with and inhibits the aggregation of beta-amyloid fibrils. Oxidative damage is inherent and possibly causal to many age related neurodegenerative diseases, and beta-amyloid plaques are a hallmark of Alzheimer’s pathology.
An in vitro study using fluorescence spectroscopy examined the effects of curcumin on the formation, extension, and destabilization of beta-amyloid fibrils (fAβ). It was found that at physiological pH and temperature, curcumin (Cur) inhibited all three.
“It thus may be reasonable to speculate that Cur could prevent the development of AD not only through scavenging reactive oxygen species but also through directly inhibiting fAβ deposition in the brain.”1
Another study, conducted at the Departments of Medicine and Neurology at UCLA, analyzed the effect of a curcumin diet on memory deficits caused by infusion of amyloid-beta fragments. This is an induced form of memory impairment often used in research. Memory was assessed using a Morris Water Maze (MWM). A MWM is used to track how long it takes a rat to find a hidden platform just below the surface in a container of water. The animals have previously learned the location of the platform, and therefore their ability to remember the location - spatial memory - is assessed. By day three following amyloid-beta infusion, the rats showed spatial memory decline. These rats were then either fed curcumin, or kept on the control diet.
“Compared to Aβ-infused rats fed the control diet, those which were fed curcumin (500 ppm) showed reduced path length and latency in finding the hidden platform, restoring performance to the levels found in the vehicle-infused controls.”2 (The vehicle-infused controls received the same surgery as the experimental group, but were not given Aβ infusion.)
Together, these studies show that curcumin not only inhibits and destabilizes amyloid-beta plaque formation, but also restores memory deficits caused by the presence of these plaques. With these types of results along with the long history of safe curcumin consumption, clinical trials on its effectiveness in AD treatment and prevention were not far off. Paradoxically, clinical trials thus far have been ambiguous. This may be attributable to the small sample size, experimental length of the trials completed so far, and the actual bioavailability of curcumin in the trials.
Consuming Curcumin
If you decide you’d like to add curcumin as part of your every day diet, there are a number of ways to go about it. You can take the most natural approach and use ground turmeric and/or yellow curry in your cooking. Curcumin constitutes about 3 percent of turmeric by weight, but can be as high as 5-10%. This may seem like a miniscule amount, but it is still physiologically relevant especially given that the other compounds in turmeric increase the bioavailability of curcumin as compared to taking curcumin alone. However, even though it’s delicious, you may not want to eat curry every day :D
Bioavailability is crucial. Consuming curcumin doesn’t necessarily mean that it’s getting to your brain in a significant amount. Depending on circumstances, some variable portion will be glucuronidated or sulfated by the digestive tract and liver. This “tagged” curcumin will not pass through the blood-brain barrier and therefore will not give us the protective benefits we’re seeking. (Tagged curcumin is also more rapidly cleared by the kidneys.)
Consuming curcumin with fats seems to increase bioavailability, which is typically the case when it’s part of a meal. An alkaloid called piperine, found in black and long pepper, also increases bioavailability through the inhibition of liver glucuronidation. So, if you’d like to take a curcumin supplement, take one encapsulated in a lipid layer or one with added piperine. Pay attention to “free curcumin bioavailability” as opposed to “absorption” or “curcumin bioavailability” as this can include the tagged forms. Paradoxically, if taking a curcumin pill, taking it 3 or more hours after a meal apparently increases bioavailability.
However you decide to consume, curcumin is a great dietary addition to anyone who wishes to lower their chances of cognitive decline with age.
Sources
1. Kenjiro Ono1, Kazuhiro Hasegawa, Hironobu Naiki, Masahito Yamada1. Curcumin has potent anti-amyloidogenic effects for Alzheimer's β-amyloid fibrils in vitro. Journal of Neuroscience Research. Volume 75, Issue 6, pages 742–750, 15 March 2004.
2. S.A. Frautschy, W. Hu, P. Kim, S.A. Miller, T. Chu, M.E. Harris-White, G.M. Cole. Phenolic anti-inflammatory antioxidant reversal of Aβ-induced cognitive deficits and neuropathology. Neurobiology of Aging, Volume 22, Issue 6, November–December 2001, Pages 993–1005. http://dx.doi.org/10.1016/S0197-4580(01)00300-1
3. Easton, Mary S. Curcumin. http://alzheimer.neurology.ucla.edu/Curcumin.html
4. Photo Credit: Will Power on Flickr under Attribution 2.0 Generic (CC BY 2.0) License.
"Education isn't something you can finish."
Nice article review... Being a south asian I also use it in every day life and in some medicinal purposes... Problem is that enough researchers are not done with it to conclude its therapeutic use or whether to discard it... Hope more accurate studies regarding these type of ayurvedic medicine come in future..
I hope to see further research as well - both here and with other ayurvedic medicine.. It would be interesting to see bioactive levels in a sample population of people like yourself who have consumed it for a long time. The problem is that it's not very water soluble and so simple blood tests don't correlate to levels in the brain.. How do you consume your turmeric @himal?
Yeah, it will be interesting indeed... I mostly consume as spices and also with hot water and milk
excellent post. I do like India Food heavy in Tumeric and Curry Spices. My favorite is local buffet here in Indianapolis, USA. Hope to remember {pun intended) buy in the store and add to my own cooking going forward. followed, upvoted and resteemed.
Thank you for sharing this information. I started taking turmeric about 6 years ago for arthritis. It took about a month but it did work. Another surprise was it help with allergies. I suffered from hay fever almost year round and took medication daily for it. Now I only have allergy attacks from certain perfumes and some cleaning products. I am so thankful for turmeric! I do take it with black pepper and whole milk for a fat. It's good to hear that this amazing spice might have other hidden values. Thanks again!
Hi @souixness thanks for the comment! How do you get your turmeric? Do you buy powdered turmeric and mix it with your milk and pepper? Do you dry/grind yourself?
Actually I but it from an supplement store on line. If I could get my hands on some rhizome, I would try and grow it myself
Does it taste like cumin?
As an extract, I'm not sure exactly what it tastes like, but as turmeric, no not really. Have you had turmeric?
Oh yes. I even fill my own capsules. Imanerd
The articles you cited are rife with poorly executed experiments. The literature has shown no reproducible beneficial effect for Curcumin on ANY disease.
http://pubs.acs.org/doi/pdf/10.1021/acs.jmedchem.6b00975
The compound is a PAINS. There is no validity to beneficial effecacy at all.
I took a look at the article you posted in the comments, which I greatly appreciate and have upvoted.
The bulk of my research on that article was done years ago when the information was personally relevant to me.. However, I did take a cursory look at whats current before writing my article and to get some additional information.
I wish now that I would have dug deeper instead of assuming things had remained ~same. Curcumin being a PAINS is obviously very significant and must be taken into account (something I didn’t know/do), but I don’t think that paper shows curcumin to be a falsehood.
For one, it seems to almost entirely focus on one specific curcuminoid, (1E,6E)-1,7-bis(4-hydroxy-3-methox- yphenyl)-1,6-heptadiene-3,5-dione (compound 1), which is isolated from a curcumin extract. This removes the potential for crucial intermolecular/synergistic effects that may be present when consuming a range of curcuminoids or turmeric. This is especially significant in clinical trials where compound 1 alone and even curcuminoids alone will not reach the brain in a significant concentration.
Second, trouble with assays does not discredit found behavioral effects like the recovered cognitive loss found in the study I cited.
Third, clinical studies have had conflicting results, but it seems (though I still haven’t done enough research) that this could be attributable to the form and route of curcumin intake and the corresponding bioavailability in the brain…
I’ve only explored a couple of the sources in the paper you posted, but I was particularly interested in the inhibition of Aβ plaque formation. In source 135 they use TEM to show that compound 1 in fact doesn’t inhibit Aβ fibril formation. (It may be significant that this was done in PBS or water and not physiological conditions.)
They did however find that cellular damage caused by Aβ fibril was mitigated by curcumin. I think this goes to show that just because something is hard to quantify immunohistochemically or with an in vitro biological assay, that doesn’t mean something significant isn’t going on..
I’m not claiming that I’m definitively right here, but I don’t think it can be said that “curcumin is a falsehood.” At this point, I'm still more inclined to think - based on the behavioral studies I have seen - that consuming curcumin in the proper form will have neuroprotective effects. However, further research is certainly needed!
I would like nothing more then for something like Curcumin to live up to the potential that the initial reports detailed. However the literature indicates a need for skepticism with this one IMO.
You're definitely right. Skepticism should certainly still be retained. Often times people are searching for answers before the scientific process is able to verify anything definitively. For me at least, as my family has a history of Alzheimer's, the current findings are encouraging enough for me to add turmeric to my daily diet. It may certainly turn out to have been a waste, but it's at least not detrimental - just a waste of time/money.
A doctor once said that mistakes should be made in order to improve. Skepticism is the way to push for answers and the more we learn the more we improve and hopefully prove it to be worthwhile.
Mother nature provides everything the body needs. Skepticism is definitely important, but to be skeptical of an ancient and widely used root/spice, in favor of a compartmentalized medical paper makes me skeptical of You.
No it does not. Its why people that eat healthy diets still get cancer, and heart disease, and develop other illnesses. Biology is complicated, and statements like the one you made above are just shortsighted.
Doesn't bother me one bit. I don't need your approval.
This is a really good article. I'd heard about the benefits of curcumin and have a lot of turmeric in the pantry that I keep forgetting to use. Perhaps if I started using it, my memory would improve! Upvoted and followed :)
I'm amazed that many Americans still don't understand that most of the disease we have today comes from bad diets which lack those essential nutrients we need for as truly healthy live, fresh fruits and veggies and utilizing the power of roots like these in daily habit.
hi upvoted
btw its look like a kunyit
what's a kunyit @meutiarachmi?
I have followed you on Steemit, please be kind enough to follow me as well.