A little ray of sunshine for Parkinson’s disease may lie with Vitamin D.

Vitamin D is the vitamin we obtain through the action of ultraviolet light on our skin. Most of the vitamin D produced is then bound in the blood and only a tiny fraction remains free and able to bind to specific vitamin D receptors now known to be located in a number of target organs in the body including the brain.

Not only that, but the area of the brain with the highest density of Vitamin D receptors is in the Substantia Nigra. This is where highly specialized cells produce Dopamine, the brain neurotransmitter vital for regulating our mood, concentration, motivation and voluntary movement.
In Parkinson’s disease many of these highly specialized cells die and the loss of Dopamine manifests itself in the form of tremor, rigidity of movement, slowness of gait and cognitive decline. Plus, thirty percent of people with Parkinson’s disease develop dementia.
It is the second most common neurodegenerative disease in Australia and remains one of the most poorly understood.

So where does Vitamin D fit in with Parkinson’s disease?

The answer to that is not yet certain, but a recently published study has linked having a higher level of Vitamin D with up to a 65% reduction in the risk of developing Parkinson’s.

These results were in a long prospective study by Paul Knekt in Finland. He showed that in a group of 3173 people aged 50 to 79, followed up over a 29 year period, those with a higher level of Vitamin D had a 65% lower risk of developing Parkinson’s compared to those with the lowest levels.

However it should be noted that all of the subjects in this study actually had lower levels of vitamin D than is recommended. This may reflect the fact that Finland is not a country associated with a lot of sun exposure for its residents. So the suggestion is that having a lower level of Vitamin D may be a predisposing factor to an increased risk of Parkinson’s disease. There is no suggestion that having a low level is in fact a cause. The study remains a starting point to determine whether giving Vitamin D as a supplement would be useful.

One of the problems recognized is that Vitamin D deficiency is widespread, even in a sunny country such as Australia. It has been reported that half to two thirds of teenagers and adults in the US have lower than desirable levels. Because it is very difficult to get sufficient Vitamin D through our diet, having adequate sun exposure is essential to help us achieve and maintain a healthy level.

How much time do we need in the sun?

Five to fifteen minutes of sunlight exposure to the face and upper arms, four to six times a week is thought to be sufficient to prevent deficiency.
Those particularly at risk of deficiency here in Australia include the elderly living in residential care and dark skinned women, especially those who are veiled. The use of sunscreen (essential to protect us from skin cancer) unfortunately prevents the synthesis of Vitamin D in the skin. Application of Factor 8 will prevent up to 95% of Vit D conversion, so a short exposure without sunscreen is recommended and outside the high-risk times of 10 am to 3 pm.

Can we get Vitamin D from our food?

We can derive a limited amount of Vitamin D from food sources. However in cases of deficiency taking a supplement would be recommended.

Vitamin D2 can be found in:

Fatty fish such as mackerel, salmon and herring
Fortified margarines
Cod liver oil
Liver
Eggs

The role of Vitamin D in the brain

The association of Vitamin D and Parkinson’s disease is intriguing and as yet not fully explained. It is believed that Vitamin D acts as a hormone rather than a vitamin, in addition to its role in bone metabolism.

Current thinking is that it may exert a neuroprotective effect through its antioxidant properties, calcium regulation of nerve cells, enhanced nerve conduction, detoxification and immunomodulation.

A UK study looked at Vitamin D levels of a group of 858 Italian men and women over the age of 65 years. Of those with dementia, 50% were vitamin D deficient. Moreover, those with the greatest deficiency had a 60% increased risk of suffering cognitive decline over the 6-year follow up period.

The role of Vitamin D relating to Alzheimer’s disease was looked at in a 2008 study where 100 people with Parkinson’s disease were compared to 100 subjects with Alzheimer’s disease and 100 healthy controls. Here the fraction of patients with the lowest levels of Vitamin D was most marked in the Parkinson’s group (23%) compared to the Alzheimer’s group (16%) and healthy group (10%) indicating support for the notion that Vitamin D plays a role in affording some neuroprotection.

Meanwhile it remains prudent to ensure that we obtain adequate sun exposure to keep our Vitamin D levels up. So go on, it’s time to enjoy some time in the sun.

References:
Emory University (2008, October 17). Lack Of Vitamin D Linked To Parkinson’s Disease.
Archives of Neurology [2010] 67 (7) : 808-811 (Knekt P, Kilkkinen A, Rissanen H, Marniemi J, Sääksjärvi K, Heliövaara M.)

During a chat with a group of ladies last week, we got onto the topic of of supplements, and which herbs and spices might be beneficial in promoting brain health. One lady advised me that every morning she pours a good dollop of flaxseed oil onto her breakfast cereal along with some L.S.A and psyllium. Plus a heaped teaspoon of turmeric.

Mmm, I remain to be convinced about the taste, although she reassured me she didn’t mind it. So, what is the deal with turmeric and why would she be adding it to her breakfast cereal?

Turmeric or Curcuma longa is an Indian spice and a member of the ginger family. It has a wonderful yellow hue that gives it’s colour to curry, mustard and piccalilli relish.

It was noted some years ago that the incidence of Alzheimer’s disease in India is about one tenth of Western societies. One study in rural North India reported an incidence of 0.62 % in those over the age of 55 years and 1.07% in those aged 65 and older. Compare that to 10% for 65 year olds in our society. There have been a number of reasons postulated as to why this should be. But one of the thoughts is that it is due to the curcumin found in turmeric and in India a huge amount of turmeric is consumed in curries on a daily basis.

The curcuminoids in the turmeric have been associated with a number of significant health benefits and a number of studies have been completed looking at how it may afford protection against neuro-degenerative disease.

Let’s have a look at some of the research.

In Alzheimer’s disease one of the hallmark findings, are of plaques in the brain made of a substance called beta amyloid. The body has it’s own defence system to try and get rid of this in the form of scavenging cells called macrophages. These travel around the brain trying to remove any amyloid it finds. One study looked at the effect of treating these macrophages with curcumin and found that the macrophages were then better able to gobble up the beta amyloid with an improvement rate of 50%.

Curcumin has potent anti-inflammatory and anti oxidant effects. It is thought that inflammation plays a role in the development of Alzheimer’s. This led to studies to see whether anti-inflammatory drugs, and or curcumin through it’s anti-inflammatory effect could be useful in treating beta amyloid build up. One study conducted at UCLA looked at the anti inflammatory effect of curcumin vs ibuprofen (a commonly used anti-inflammatory drug). Using rats with beta amyloid in their brains, both curcumin and the ibuprofen were shown to provide equivalent protection from the inflammatory damage caused by the beta amyloid. The curcumin reduced the number of plaques in the rat brains by up to 80% at low dose and the rats given the curcumin performed better on spatial memory tests compared to the control group. Curcumin can cross the blood brain barrier and binds to amyloid protein fragments, which can then no longer clump together to form plaques.
However follow up clinical trials in patients with Alzheimer’s disease who were prescribed anti-inflammatory drugs such as Ibuprofen unfortunately only produced limited or negative results. Likewise the ADAPT cognitive function tests using Naprosyn similarly showed no benefit in improving cognitive function in older adults. There remains the possibility that the NSAID’s could be useful if taken in the years prior to any cognitive decline. This has yet to be shown.

Curcumin and Vitamin D

Moving back to curcumin and its possible role with Vitamin D. In 2009 UCLA researchers discovered that Vitamin D together with curcumin might help to stimulate the immune system to clear the brain of amyloid beta.
A small study was undertaken with 9 patients with Alzheimer’s disease, 3 healthy controls and one subject with mild cognitive impairment. Blood samples were collected and a type of white cell, monocytes (which can transform into macrophages) were isolated and then incubated with amyloid beta, Vitamin D3 and either natural or synthetic curcumin.
The synthetic curcumin was devised as naturally occurring curcumin was found to be less readily absorbed and so is less potent.

The researchers found that the curcuminoids enhanced the surface binding of amyloid beta to macrophages and that Vitamin D also strongly stimulated the uptake and absorption of amyloid beta by the macrophages in the majority of patients.

A previous study by the same team had demonstrated that MGAT 111 and TLR-3 genes are the genes associated with the immune system’s ability to ingest amyloid beta. Dr Milan Fiala found that there were two types of Alzheimer’s patients: type one who did respond positively to curcuminoids and type two who did not. He noted that as the curcumin and Vitamin D work differently in the immune system, it might be that either a combination of the two or each used alone, might be more effective depending on the individual. He suggests larger and more studies using Vitamin D and curcumin are necessary to see if this would be the case.

How does the curcumin exert its effect?

Dr A Ramamoorthy at the university of Michigan has shown that the curcumin inserts itself into cell membranes, changing the physical properties of the membrane rather than interacting directly with the membrane proteins.
He is is now working on looking at determining the relative potency of a variety of curcuminoids derivatives which could potentially lead to new compounds being formulated as treatments. He is also investigating the effects on how curcumin exerts its effects on the formation of amyloid.

So if eating curry with turmeric may assist in keeping our minds sharp as we age, how much should we be eating? According to Dr Sally Frautschy, Associate Professor of UCLA (who eats curry four times a week), one tablespoon or 200mg per day.

But I think I still prefer to eat my turmeric in curry rather than on my breakfast cereal though.

What about you? How do you take your turmeric?