Vitamin D, Omega-3 May Help Clear Amyloid Plaques Found in Alzheimer’s

April 6, 2013

A team of academic researchers has pinpointed how vitamin D3 and omega-3 fatty acids may enhance the immune system’s ability to clear the brain of amyloid plaques, one of the hallmarks of Alzheimer’s disease. In a small pilot study published in the Feb. 5 issue of the Journal of Alzheimer’s Disease, the scientists identified key genes and signaling networks regulated by vitamin D3 and the omega-3 fatty acid DHA (docosahexaenoic acid) that may help control inflammation and improve plaque clearance.

omega 3

Previous laboratory work by the team helped clarify key mechanisms involved in helping vitamin D3 clear amyloid-beta, the abnormal protein found in the plaque. The new study extends the previous findings with vitamin D3 and highlights the role of omega-3 DHA.

“Our new study sheds further light on a possible role for nutritional substances such as vitamin D3 and omega-3 in boosting immunity to help fight Alzheimer’s,” said study author Dr. Milan Fiala, a researcher at the David Geffen School of Medicine at UCLA.

For the study, scientists drew blood samples from both Alzheimer’s patients and healthy controls, then isolated critical immune cells called macrophages from the blood. Macrophages are responsible for gobbling up amyloid-beta and other waste products in the brain and body.

The team incubated the immune cells overnight with amyloid-beta. They added either an active form of vitamin D3 called 1alpha,25–dihydroxyvitamin D3 or an active form of the omega-3 fatty acid DHA called resolvin D1 to some of the cells to gauge the effect they had on inflammation and amyloid-beta absorption.

Both 1alpha, 25-dihydroxyvitamin D3 and resolvin D1 improved the ability of the Alzheimer’s disease patients’ macrophages to gobble-up amyloid-beta, and they inhibited the cell death that is induced by amyloid-beta. Researchers observed that each nutrition molecule utilized different receptors and common signaling pathways to do this.

Previous work by the team, based on the function of Alzheimer’s patients’ macrophages, showed that there are two groups of patients and macrophages. In the current study, researchers found that the macrophages of the Alzheimer’s patients differentially expressed inflammatory genes, compared with the healthy controls, and that two distinct transcription patterns were found that further define the two groups: Group 1 had an increased transcription of inflammatory genes, while Group 2 had decreased transcription. Transcription is the first step leading to gene expression.

“Further study may help us identify if these two distinct transcription patterns of inflammatory genes could possibly distinguish either two stages or two types of Alzheimer’s disease,” said study author Mathew Mizwicki, an assistant researcher at the David Geffen School of Medicine at UCLA.

While researchers found that 1alpha,25-dihydroxyvitamin D3 and resolvin D1 greatly improved the clearance of amyloid-beta by macrophages in patients in both groups, they discovered subtleties in the effects the two substances had on the expression of inflammatory genes in the two groups. In Group 1, the increased-inflammation group, macrophages showed a decrease of inflammatory activation; in Group 2, macrophages showed an increase of the inflammatory genes IL1 and TLRs when either 1alpha,25-Dihydroxyvitamin D3 or resolvin D1 were added.

More study is needed, Fiala said, but these differences could be associated with the severity of patients’ nutritional and/or metabolic deficiencies of vitamin D3 and DHA, as well as the omega-3 fatty acid EPA (eicosapentaenoic acid).

“We may find that we need to carefully balance the supplementation with vitamin D3 and omega-3 fatty acids, depending on each patient in order to help promote efficient clearing of amyloid-beta,” Fiala said. “This is a first step in understanding what form and in which patients these nutrition substances might work best.”

According to Fiala, an active (not oxidized) form of omega-3 DHA, which is the precursor of the resolvin D1 used in this study, may work better than more commercially available forms of DHA, which generally are not not protected against the oxidation that can render a molecule inactive.

The next step is a larger study to help confirm the findings, as well as a clinical trial with omega-3 DHA, the researchers said.

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Activities for People with Alzheimer’s Disease

March 10, 2013

Melanie, a music therapist, regularly played live classical music for a Chicago woman who was in the late stages of Alzheimer’s. The woman used to frequent the opera and classical music venues, but for some reason, the songs did not seem to resonate with her. Melanie then played a Frank Sinatra CD. Immediately, the woman’s eyes lit up. Frank’s crooning, instead of the live sounds of the flute and guitar, really moved her.

For people with Alzheimer’s disease, a successful activity, whether it’s listening to music or playing a game, helps create meaning and pulls from past interests, says Cameron Camp, Director and Senior Research Scientist, Myers Research Institute of Menorah Park Center for Senior Living. Activities allow the person to be part of a family and community and gives him or her the chance to be more engaged with life.

“The biggest thing to remember with a person with dementia is that they’re a person with dementia,” says Camp.

There will always be part of that individual who wants to help, participate, and succeed. Although as the caregiver you will want to find activities that take in account lost abilities, you should always focus on the person and not the disease. Even if your loved one does not remember the activity, the joy he feels from taking part in a project, big or small, leaves a positive effect and contributes to an overall sense of happiness.

Why Activities Help

Although they don’t necessarily slow the progression of Alzheimer’s, activities do improve your loved one’s quality of life. Games, housework, and the other activities listed below can lessen agitation and depression. Activities can also help maintain motor skills that aid daily tasks such as buttoning a shirt or recognizing household objects. Projects that match a person’s skill level also give her a sense of ownership and independence. And when your loved one completes an activity, she gains a sense of accomplishment.

Activities also help relieve a caregiver’s frustration by keeping the loved one stimulated and by fostering emotional connection and self expression.

General Guidelines

  • Create meaningful activities. This is not about filling the dayñno busy work. Try for activities that your loved one used to do and enjoy.
  • Assess skills. Can they sort objects by size or color? Can they button shirts and zip up jackets? Can they follow written commands? Modify activities to make them more or less challenging to fit the skills of your loved one.
  • Play up past interests. People with Alzheimer’s often maintain old habits and abilities. Try adapting these skills into smaller and more manageable components. Create games based on their interests.
  • Make activities failure free. If your loved one is involved and happy, don’t correct him. The goal is to engage the person with dementia and encourage a sense of success.
  • Keep activities simple. Too many decisions may frustrate people with Alzheimer’s. Keep crowds and noise to a minimum.
  • Give both verbal and visual instruction. Feel free to tell and to show. If your loved one is accepting, even guide his arms gently as you instruct.
  • Do activities that let your loved one manipulate materials. For people with advanced dementia, avoid small objects that might be swallowed.
  • Select the best time of day for your loved one. More energy in the morning? Go for a walk. More focused in the afternoon? Try an art project.
  • Keep the work area safe. Work with unbreakable plastics; keep the surface clean, uncluttered and well lit.
  • Be prepared with alternate activities. If your loved one doesn’t connect with an activity, be sure to have another ready. Through trial and error, you’ll find activities that best suit your loved one.
  • And don’t be afraid to try something new, to see if it arouses curiosity.
  • Repeat favorite activities, and establish a routine. Note the activities your loved one enjoys. Although the patient may not remember them the next time, she may repeat the processes instinctively. While doing familiar activities, such as sorting objects, keep the procedures the same, but try different content from day to day to keep it fresh for her and for you.

Activities to Try

Hobbies and Crafts

  • Simplify old hobbies. For those who liked to knit, try a simpler pattern. If they enjoy crossword puzzles, try a jigsaw puzzle with large pieces.
  • Garden together. Basic, repetitive tasks such as raking may fulfill your loved one, especially if he gardened in the past. Use herbs or other nontoxic plants that arouse multiple senses.
  • Find her inner artist. Paint with watercolors, draw with crayons. People with Alzheimer’s may not judge themselves as harshly as they once did, so they may finally free their inner artists.

Exercise

Exercise helps everyone, including people with dementia, to maintain a healthy appetite, get a good night’s sleep and achieve a happy, endorphin-boosted outlook.

  • Take a walk.
  • Go for a swim.
  • Participate in a yoga or tai chi class at your local community center. Simplify by picking only a couple of moves to try, or watch a yoga tape together.
  • Visit a therapeutic garden. These provide walking paths, bird feeders accessible to those in wheelchairs, and sturdy furniture for older adults. Gardens provide a safe environment to reconnect with nature, get a little exercise and absorb some vitamin D.

Games

  • Sorting games. Sort objects by color, shape or design. Infuse the game with your loved one’s favorite hobbies. For example, baseball fans can sort cards by team or position. If your loved one enjoyed carpentry, have him match tools with their names.
  • Play ball. Use balloons or large, soft balls to play catch.
  • Shopping scavenger hunt: Collect sales ads from newspapers with your loved one. While you travel the aisles with your loved one, give her a list of items to search for in the grocery store. Up the ante and search for items with the lowest cost.
  • Solve puzzles. Create jigsaw puzzles from family photos. Cut them into two or three large pieces to start. You can divide the photo into more pieces to make the activity more challenging.
  • Shuffle a prayer. Type lines of their favorite prayer on separate pieces of paper for re-ordering.

Daily Tasks and Chores

  • Read together. Read the paper or book with large print. Take turns, and have fun.
  • Bake together. Pick simple recipes for cookies, muffins and pancakes. Put him in charge of part of the recipe or an easier task, such as stirring.
  • Clean up together. Ask your loved one to help you around the house. By doing simple tasks such as wiping off the table, sweeping the patio, washing the silverware, folding towels or simply holding open the trash bag as you put things into it, she becomes part of a team. Remember that she may not perform the tasks to perfection, but it is the process that is important.

Help Others

By helping others, you can help your loved one combat feelings of uselessness.

  • Start a food drive. Collect canned goods and other nonperishable items from your neighbors or grocery store. Get your loved one involved, whether she selects the items or helps you load the bags.
  • Participate in a toy drive. Collect, wrap and take the toys together to a women’s shelter or orphanage.

Reminisce

  • Talk about old times. Encourage your loved one to remember a favorite summer, first day of school or wedding day. Keep in mind, though, that painful memories may also resurface.
  • Watch family videos. Pull out old movies or make a new one where family members discuss their fondest memories of your loved one.
  • Go through photo albums. Old pictures can trigger pleasant memories.
  • Watch a favorite movie or TV show from their past.
  • Go through a box of trinkets from their life.
  • Write down family stories. Keep a book of the memories your loved one has related, and ask her to read it to the grandchildren.

Music

Some music therapists have found that adults with advanced Alzheimer’s often respond to music, and especially music from their past. In fact, researchers have found that the ability to process music remains intact into the late stages of the disease.

  • Trigger old memories. Play their favorite hymn, music from their youth or well-known popular songs of their day. Make a CD of their favorite songs.
  • Dance. If they enjoyed dancing, they probably still do, or at least will respond to the sight of others dancing. You could attend a dance class and sit in the audience.
  • Sing along. People with Alzheimer’s often retain melodies and words to popular songs. Print out the words to a song and sing along with a CD. Or sing with a group while someone plays a piano or guitar.

Pets

Here’s a source of unconditional love. Pets convey their needs in ways that everyone, including people with Alzheimer’s, easily understands, and they provide comfort. Relax by watching birds from a window or fish in an aquarium.

Sensory

Remember that as Alzheimer’s advances, your loved one will retain all of his or her senses.

  • Talk to him. While your loved one may not respond, this doesn’t mean that he is not aware of your presence.
  • Comb her hair.
  • Moisturize her skin.
  • Shave his face.
  • Give her a manicure or a hand massage with scented oil.
  • Give her dolls with zippers and buttons to play with or soft teddy bears, textured cloth, or fur to stroke.
Citation

 

Alzheimer’s Therapeutic Activities

January 7, 2013

How can therapeutic activities help manage the symptoms of Alzheimer’s?

Planning structured, individualized activities that involve and interest the person with Alzheimer’s may reduce many of the more disturbing behavioral symptoms of AD, such as agitation, anger, frustration, depression, wandering or rummaging. Health professionals who work with Alzheimer’s patients say therapeutic activities should focus on the person’s previous interests, cue the person to old and recent memories and take advantage of the person’s remaining skills while minimizing the impact of skills that may be compromised.

What kinds of therapeutic activities are best?

Successful activities support a person’s sense of self – bringing out their skills, memories and habits – and reinforce the person’s sense of being in a group, which can provide friendship, mutual support and spiritual connectedness.

Any number of activities may be beneficial depending on the individual, and different activities may affect certain symptoms but not others. (For example, music therapy may improve eating in some people but not others.) Any former hobby or interest of the person is a candidate, from gardening, cooking, painting and drawing, to singing, playing musical instruments or listening to music, etc. Routine is essential: Activities that are done regularly, perhaps even at the same time every day if possible, may help establish routine and increase the person’s sense of stability.

Some of the therapeutic activities that have been shown in rigorous research studies to reduce certain problem behaviors in people with Alzheimer’s are:

  • playing music of the person’s choosing
  • one-on-one interaction
  • playing videotapes of family members;
  • walking and light exercise
  • pet therapy

Several programs that combine various therapeutic activities have also shown favorable results in people with Alzheimer’s. These include a multifaceted program of music, exercise, crafts and relaxation, and structured sessions combining meditation, relaxation, sensory awareness and guided imagery, so-called mind-over-body techniques designed to calm and soothe.

Where can I learn more about beneficial activities?

Your doctor, nursing staff or social worker should be able to help you determine what types of activities might be best and direct you to community resources that can help. Medical centers or health care service providers that serve Alzheimer’s patients, such as adult care centers or home health care networks, may sponsor programs or know about programs in your area.

One example of a beneficial form of therapy for people with Alzheimer’s is a therapy garden.

Therapeutic gardens, specially maintained gardening facilities that help people remain connected with nature, provide benefits for a wide variety of people who are ill or recovering from illness. They are used to help people recovering from surgery in healthcare facilities, for those who are undergoing physical rehabilitation and for individuals with Alzheimer’s disease who are living in special care residences or who are living at home. Research indicates that physical as well as visual access to nature helps people recover from illness quicker, reduces stress and lowers blood pressure. Spending time outside helps a person maintain circadian rhythms (the sleep/wake cycle). There is also natural absorption of vitamin D when exposed to sunlight for brief periods of time, which is important for maintaining strong bones.

Access to outdoor environments, in specially designed gardens can be beneficial to the physical, social, psychological and spiritual health of a person. A therapeutic garden can provide exercise to a patient through normal activities such as planting, weeding, walking and bending. Many of the same activities that occur inside a residence can be continued outdoors. For example, having access to a putting green is a good activity for people who have played golf throughout their lives. Adding play equipment to a garden will give visitors something to do with the resident while they visit. These are elements of a garden that help a person stay connected to the world around them. Therefore, everyone who uses the garden will benefit.

Gardening and bird watching are very popular activities for people of all ages. Watching a brilliant sunset, smelling the fragrance of a lilac tree and listening to the sounds of water cascading in a fountain are all wonderful ways to excite the senses in a positive way. These activities are very important because they help a person remain connected to the world around them. It is important for a person with Alzheimer’s to be able to continue enjoying outdoor activities they have done throughout their lives. (Note: this outdoor area must be safe and secure.) Often, we do not know how to reach a person with Alzheimer’s disease, and creating environments that support their needs will help us better understand who they are.

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Vitamin D May Be Tied to Women’s Cognitive Performance

December 2, 2012

Two new studies appearing in the Journals of Gerontology Series A: Biological Sciences and Medical Sciences show that vitamin D may be a vital component for the cognitive health of women as they age. Higher vitamin D dietary intake is associated with a lower risk of developing Alzheimer’s disease, according to research conducted by a team led by Cedric Annweiler, MD, PhD, at the Angers University Hospital in France.

Similarly, investigators led by Yelena Slinin, MD, MS, at the VA Medical Center in Minneapolis found that low vitamin D levels among older women are associated with higher odds of global cognitive impairment and a higher risk of global cognitive decline. Slinin’s group based its analysis on 6,257 community-dwelling older women who had vitamin D levels measured during the Study of Osteopathic Fractures and whose cognitive function was tested by the Mini-Mental State Examination and/or Trail Making Test Part B.

Very low levels of vitamin D (less than 10 nanograms per milliliter of blood serum) among older women were associated with higher odds of global cognitive impairment at baseline, and low vitamin D levels (less than 20 nanograms per milliliter) among cognitively-impaired women were associated with a higher risk of incident global cognitive decline, as measured by performance on the Mini-Mental State Examination.

Annweieler’s team’s findings were based on data from 498 community-dwelling women who participated in the Toulouse cohort of the Epidemiology of Osteoporosis study. Among this population, women who developed Alzheimer’s disease had lower baseline vitamin D intakes (an average of 50.3 micrograms per week) than those who developed other dementias (an average of 63.6 micrograms per week) or no dementia at all (an average of 59.0 micrograms per week).

These reports follow an article published in the Journals of Gerontology Series A earlier this year that found that both men and women who don’t get enough vitamin D — either from diet, supplements, or sun exposure — may be at increased risk of developing mobility limitations and disability.

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Vitamin D Could Hold Vital Key to Arresting Development of Alzheimer’s Disease

November 14, 2012

Scientists at London’s Kingston University have uncovered evidence that lack of a particular form of vitamin D is associated with Alzheimer’s disease.

Working in collaboration with researchers from Brighton and Sussex Medical School and the Sussex Partnership NHS Foundation, the Kingston researchers spent six months analysing blood samples from patients with Alzheimer’s. They compared test results from those not being treated with any drugs to those from people on medication and a further group who did not have the condition.

Lead researcher Professor Declan Naughton, from Kingston University’s School of Life Sciences, said the results had revealed some important facts. Alzheimer’s patients who were not using medication had very poor stores of vitamin D2 — the type originating from food such as oily fish, rather than that obtained from exposure to the sun.

“The vitamin was either non-existent or in such low quantities that it could barely be measured,” he explained. “In comparison, people in the study who were either being treated with drugs to control their Alzheimer’s or who didn’t have the condition at all showed far higher levels.”

In a further twist, the scientists found indications that Acetylcholinesterase inhibitors — used to treat the early stages of Alzheimer’s — might play a role in actually “switching on” the body’s absorption of vitamin D2.

“There are several different types of vitamin D that can be active in the body,” Professor Naughton explained. “The key point in this study was that a blood test, which we developed at Kingston University, was for the first time able to accurately measure which, if any, of the different variations of vitamin D were present in Alzheimer’s patients.”

There had been speculation in the scientific community in the past that vitamin D, or a lack of it, might have a role to play in the development of Alzheimer’s. However, this was believed to be the first time scientists had pinpointed the connection with the vitamin D2 metabolite, Professor Naughton said.

Although more research was still needed, the findings could eventually pave the way for medical intervention to restore levels of that particular strand of vitamin D, he added. Such an approach had the potential to have a marked impact on the devastating condition, which currently affects almost half a million people in the United Kingdom alone. “Further investigations are now needed to determine whether simple dietary advice or giving a specific supplement could restore beneficial levels in Alzheimer’s patients,” Professor Naughton said.

Vitamin D plays a key role in the development of healthy bodies. It helps to form and maintain strong teeth and bones and is thought to protect against a number of diseases such as cancers, cardiovascular conditions and neurological problems. “Most people associate vitamin D with exposure to the sun. The idea that a lack of the storage form originating from foods such as oily fish and egg yolks might be implicated in the development and progression of Alzheimer’s definitely merits further research,” Professor Naughton said.

The scientists’ study, entitled Low 25OH Vitamin D2 Levels Found in Untreated Alzheimer’s Patients Compared to Acetylcholinesterase Inhibitor Treated and Controls, has been published in international journal Current Alzheimer Research.

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15 Ways to Help Someone With Dementia Avoid Falling

November 5, 2012

You can’t completely prevent falls — accidents do happen. Adults over age 65, and older adults with dementia in particular, are at a higher risk of falling, for some well-known reasons. These include a higher use of prescription drugs, more night waking, shuffling and other coordination problems, and weakening musculature and balance.

Most falls in people with dementia are “multifactorial,” meaning that a combination of problems contributed to the fall. This makes it especially hard to eliminate falls altogether. But it’s almost always possible to identify risk factors that can be changed or risks that can be compensated for.

What you can do:

With your doctor’s help

1. Understand what you’re dealing with. Identify, with a doctor’s help, which risk factors for falls your loved one has, besides dementia (which is itself considered a risk factor). The list varies by individual, but for many people with dementia these include such common problems as poor eyesight, poor balance, arthritis, and generalized frailty. People with dementia may also have a shuffling gait, muscle weakness due to past stroke, or neurological problems.

2. Minimize or avoid medications that have been linked to increased falls. Review a complete medication list with the doctor, and ask which ones might cause increased confusion or worse balance in a person with dementia.

Those to especially look out for include drugs from a class known as anticholinergics, which includes drugs for overactive bladder, itching/allergy, vertigo, nausea, and certain drugs for nerve pain or depression. (Diphenhydramine, or Benadryl, is a commonly used anticholinergic that’s often included in over-the-counter sleep aids and PM-version painkillers.) People with dementia are also more likely to fall when taking sedatives, tranquilizers, and antipsychotics. Finally, blood pressure medicines can sometimes work too well and cause blood pressure to fall when a person stands.

3. Ask the doctor about leg strength, gait, and balance evaluations. These tests help determine physical risk factors. A doctor (or a physical therapist, to whom you may be referred for testing) will watch whether your loved one uses both hands to rise from a chair, for example, which indicates muscle weakness.

4. Ask about vitamin D supplementation. Many (but not all) older adults are deficient in vitamin D. Studies have found that treating vitamin D deficiency does reduce the chance of future falls. The doctor can help identify the right supplemental dose.

5. Ask about osteoporosis. Whether or not they also have dementia, adults with osteoporosis are more likely to suffer injuries if they do fall. Note: Both older men and older women can suffer from porous bone. But since osteoporosis is more common in women, all women over age 65 should be screened at least once.

With other experts’ help

6. Consider asking for a referral to a physical therapist or occupational therapist. These experts can work with your loved one to develop exercises that shore up weak spots. They can also evaluate the use of a cane or walker to see if the device (as currently being used) is more help or hindrance. Because forgetting to use devices is a common problem with dementia, a therapist may suggest ways to get around this.

7. Make sure your loved one has an annual eye exam. Low vision is a huge risk factor for falls, and many vision problems come on gradually but steadily. Some, like cataracts, are easily treatable. Also be cautious with bifocal glasses; although they’re convenient, one study found increased falls when people wore bifocals compared to monofocals, possibly because bifocals can make it harder to gauge depth and steps properly.

8. Keep up with foot care. Trimmed nails help people walk more comfortably and therefore properly, yet this is an often-overlooked aspect of eldercare. A podiatrist can also check out other foot-pain issues that may be affecting gait and balance.

9. Get a home-safety assessment. Social workers and geriatric care managers routinely perform these. An expert comes to the person’s home and targets danger spots (including fall risks) and suggests easy improvements. This assessment can focus specifically on the needs of someone with dementia.

10. Consider exercise classes. If your loved one is capable, consider an exercise class to improve strength and balance, such as ti chi or yoga for seniors. Even people with dementia can benefit. Bonus: It might be something you can do together, getting you out of the house.

Around the house

11. Make sure slippers and shoes are safe and stable. Discourage walking around in stocking feet, loose slippers, or flimsy open-heel styles. Overlooked footwear dangers include new shoes with smooth, unscuffed soles and walking shoes with heavy treads that “catch” on carpets.

12. Remove tripping hazards around where the person walks. Scatter rugs are a top tripper, for example. In the bathroom, you can lay a towel or rug in front of the tub or shower when the person is exiting, if the floor is cold; then pick it up right away.

Also tame unruly extension cords. Better than taping them to the floor is to remove them altogether. Remove piles of old newspapers and magazines and other clutter.

13. Maintain good household lighting. Poor vision is a leading fall-maker. Watch for darkened hallways and stairs that might need more light. Replace burned-out bulbs.

Don’t forget night lighting. Keep the night path to the bathroom lit. Consider using holiday lights, spaced nightlights, motion-detector lights, or simply leaving the hall or bathroom light on.

14. Install grab bars in showers, bathtubs, and near toilets. These allow your loved one to catch himself or herself in a fall. Regular towel bars are insufficient; they can be pulled off the wall if grabbed during a fall, often worsening the accident.

15. Brainstorm ways to limit the potential hazard of pets that cause falls. For example, you might consider whether a pet could be limited to one area of the house, or let it wander freely only under supervision. Beware of chew toys and bones that get scattered on the floor, too. Children’s toys can be another hazard.

Citation

 

Vitamin D Mitigates Age-related Cognitive Decline

October 29, 2012

J Neuroinflammation. 2012 Oct 25;9(1):244. [Epub ahead of print]

Vitamin D mitigates age-related cognitive decline through the modulation of pro-inflammatory state and decrease in amyloid burden.

Briones TL, Darwish H.

ABSTRACT:

Increasing evidence shows an association between the use of vitamin D and improvement in age-related cognitive decline. In this study, we investigated the possible mechanisms involved in the neuroprotective effects of vitamin D on age-related brain changes and cognitive function.

METHODS:

Male F344 rats aged 20 months (old) and 6 months (young) were used and randomly assigned to either vitamin D supplementation or no supplementation (control). A total of n = 39 rats were used in the study. Rats were individually housed and the supplementation group received a subcutaneous injection of vitamin D (1, alpha25-dihydroxyvitamin D3) 42 I.U./Kg for 21 days.

Control animals received equal volume of normal saline. Behavioral testing in water maze and spontaneous object recognition tasks started on day 14. Levels of interleukin (IL)-1beta and IL-10 were quantified to assess inflammatory state. Also, beta amyloid (Abeta) clearance and Abeta load were measured.

RESULTS:

Our results show that: (1) aged rats demonstrated significant learning and memory impairment overall compared to younger animals. However, the age-related decline in learning and memory was ameliorated by the supplementation of vitamin D. No vitamin D effect on learning and memory was seen in the young animals; 2) the pro-inflammatory cytokine IL-1beta is significantly increased while the anti-inflammatory cytokine IL-10 is significantly decreased in the aged rats compared to the young animals; but this age-related change in inflammatory state was mitigated by vitamin D supplementation. No effects of vitamin D were seen on the IL-1beta and IL-10 expression in the young rats; (3) vitamin D increased Abeta clearance and decreased amyloid burden in the aged rats while no significant difference was seen between the young animal groups.

CONCLUSIONS:

Our data suggest that vitamin D supplementation modulated age-related increase in pro-inflammatory state and amyloid burden. It is possible that these effects of vitamin D mediated the decrease memory impairment seen in the aged rats making it a useful therapeutic option to alleviate the effects of aging on cognitive function.

Citation

 

Vitamin D, Cognition, and Dementia

September 26, 2012

Neurology. 2012 Sep 25;79(13):1397-405.

Vitamin D, cognition, and dementia: A systematic review and meta-analysis.

Balion C, Griffith LE, Strifler L, Henderson M, Patterson C, Heckman G, Llewellyn DJ, Raina P.

Source

Correspondence & reprint requests to Dr. Balion: balion@hhsc.ca.

Abstract

OBJECTIVE:

To examine the association between cognitive function and dementia with vitamin D concentration in adults.

METHODS:

Five databases were searched for English-language studies up to August 2010, and included all study designs with a comparative group. Cognitive function or impairment was defined by tests of global or domain-specific cognitive performance and dementia was diagnosed according to recognized criteria. A vitamin D measurement was required. Two authors independently extracted data and assessed study quality using predefined criteria. The Q statistic and I(2) methods were used to test for heterogeneity. We conducted meta-analyses using random effects models for the weighted mean difference (WMD) and Hedge’s g.

RESULTS:

Thirty-seven studies were included; 8 contained data allowing mean Mini-Mental State Examination (MMSE) scores to be compared between participants with vitamin D <50 nmol/L to those with values ≥50 nmol/L. There was significant heterogeneity among the studies that compared the WMD for MMSE but an overall positive effect for the higher vitamin D group (1.2, 95% confidence interval [CI] 0.5 to 1.9; I(2) = 0.65; p = 0.002). The small positive effect persisted despite several sensitivity analyses. Six studies presented data comparing Alzheimer disease (AD) to controls but 2 utilized a method withdrawn from commercial use. For the remaining 4 studies the AD group had a lower vitamin D concentration compared to the control group (WMD = -6.2 nmol/L, 95% CI -10.6 to -1.8) with no heterogeneity (I(2) < 0.01; p = 0.53).

CONCLUSION:

These results suggest that lower vitamin D concentrations are associated with poorer cognitive function and a higher risk of AD. Further studies are required to determine the significance and potential public health benefit of this association.

 

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