RSS Feed Print
Lutein and zeaxanthin - and improved cognitive function in the elderly
onward
Posted: Monday, October 29, 2012 7:02 PM
Joined: 12/20/2011
Posts: 217


 

 

A possible role for lutein and zeaxanthin in cognitive function in the elderly

 

Elizabeth J Johnson  



 

Am J Clin Nutrvol. 96 no. 5 1161S-1165S  


Abstract


Epidemiologic studies suggest that dietary lutein and zeaxanthin may be of benefit in maintaining cognitive health.


Among the carotenoids, lutein and zeaxanthin are the only two that cross the blood-retina barrier to form macular pigment (MP) in the eye. They also preferentially accumulate in the human brain.


Lutein and zeaxanthin in macula from nonhuman primates were found to be significantly correlated with their concentrations in matched brain tissue. Therefore, MP can be used as a biomarker of lutein and zeaxanthin in primate brain tissue. This is of interest given that a significant correlation was found between MP density and global cognitive function in healthy older adults.


An examination of a relation between cognition and lutein and zeaxanthin concentrations in the brain tissue of decedents from a population-based study in centenarians found that zeaxanthin concentrations in brain tissue were significantly related to antemortem measures of global cognitive function, memory retention, verbal fluency, and dementia severity after adjustment for age, sex, education, hypertension, and diabetes.


In univariate analyses, lutein was related to recall and verbal fluency, but the strength of the associations was attenuated with adjustment for covariates.


However, lutein concentrations in the brain were significantly lower in individuals with mild cognitive impairment than in those with normal cognitive function.


Last, in a 4-mo, double-blinded, placebo-controlled trial in older women that involved lutein supplementation (12 mg/d), alone or in combination with DHA (800 mg/d), verbal fluency scores improved significantly in the DHA, lutein, and combined-treatment groups.


Memory scores and rate of learning improved significantly in the combined-treatment group, who also showed a trend toward more efficient learning.


When all of these observations are taken into consideration, the idea that lutein and zeaxanthin can influence cognitive function in older adults warrants further study.
 

 

http://ajcn.nutrition.org/content/96/5/1161S.abstract?sid=7c19ab82-e988-48d3-9d6e-16f80f562af1 


Lane Simonian
Posted: Tuesday, October 30, 2012 9:22 AM
Joined: 12/12/2011
Posts: 4854


Interesting because macular degeneration may be driven by peroxynitrites, and leutin and zeaxanthin are both used to try to slow down the progression of macular degeneration.  Leutin and zeaxanthin scavenge peroxynitrites and/or peroxynitrous acid. 

 

The reaction of peroxynitrite with zeaxanthin.

Source

Laboratorium für Anorganische Chemie, Eidgenössische Technische Hochschule, Zürich, Switzerland.

Abstract

The oxygenated carotenoids zeaxanthin and lutein, found in the macular area of the retina, may offer protection against or repair of oxidative damage associated with the degenerative diseases of aging...

 

http://www.ncbi.nlm.nih.gov/pubmed/9706738 

 

By extension, the best peroxynitrite scavengers will "offer protection against or repair oxidative damage" in the hippocampus in Alzheimer's disease. 


onward
Posted: Tuesday, October 30, 2012 2:56 PM
Joined: 12/20/2011
Posts: 217


 Lane, thank you.

 

_______________________________________________________

 

For anyone interested... This is from WebMD:


Foods with lutein and zeaxanthin:
 

Kale (1 cup) 23.8 mg

Spinach (1 cup) 20.4 mg

Collard greens (1 cup) 14.6 mg

Turnip greens (1 cup) 12.2 mg

Corn (1 cup) 2.2 mg

Broccoli (1 cup) 1.6 mg



http://www.webmd.com/eye-health/lutein-zeaxanthin-vision


_____________________________

 

 

 


Another article of interest::

 

Nutritional Biomarkers in Alzheimer's Disease: The Association between Carotenoids, n-3 Fatty Acids, and Dementia Severity  

 

Abstract

 

Carotenoids are fat-soluble antioxidants that may protect polyunsaturated fatty acids, such as n-3 fatty acids from oxidation, and are potentially important for Alzheimer's disease (AD) prevention and treatment.


Fasting plasma carotenoids were measured in 36 AD subjects and 10 control subjects by HPLC.


Correlations between plasma carotenoid levels, red blood cell (RBC) n-3 fatty acids, and dementia severity were examined in AD patients.

 

Moderately severe AD patients (MMSE=16–19) had much lower plasma levels of two major carotenoids: lutein and beta-carotene, compared to mild AD patients (MMSE=24–27) or controls.


Among AD patients, variables (lutein, beta-carotene, RBC docosahexaenoic acid (DHA) and LDL-cholesterol) were significantly correlated with MMSE.


A lower MMSE score was associated with lower lutein, beta-carotene and RBC DHA levels, and a higher LDL-cholesterol level.


These variables explained the majority of variation in dementia severity (55% of variance in MMSE). Lutein, beta-carotene and beta-cryptoxanthin were positively correlated with RBC DHA in AD patients.

 

The association between higher carotenoids levels and DHA and higher MMSE scores, supports a protective role of both types of nutrients in AD. These findings suggest targeting multiple specific nutrients, lutein, beta-carotene, and DHA in strategies to slow the rate of cognitive decline.



http://iospress.metapress.com/content/w54556121047537t/ 

 

 

 


Lane Simonian
Posted: Tuesday, October 30, 2012 4:59 PM
Joined: 12/12/2011
Posts: 4854


Just to continue the theme from here and from several of Onward's previously helpful posts. 

 

VI.  Peroxynitrite Scavengers

Natural Vitamin E as mixed tocopherols. Only the gamma tocopherol reduces damage of peroxynitrite.77 78 Without presence of adequate gamma tocopherol, alpha tocopherol alone can displace gamma tocopherol in cells: both are needed.79 Alpha tocopherol reactivates glutathione80 and protects cells from chemical injury.81 82 Vitamin E is usually given separately since it is fat-soluble. 

A mixture of carotenoids is also needed to scavenge peroxynitrite. Carotenoids may be more organ-specific. An inclusion of gingko (brain), silymarin (liver), bilberry (collagen stabilizing, capillary permeability, vision), cranberry (urinary) and other mixed caretenoids is recommended. Silimarin scavenges peroxynitrite and also enhances the detoxification enzyme superoxide dismutase (SOD) activity in cells,83 84 and SOD is important in helping to stop the neural sensitization vicious cycle. 

Bilberry is a potent flavinoid antioxidant that reduces blood vessel and capillary fragility and permeability85 and improves damaged neurologic function.86 Bioflavinoids help body cells makemore glutathione87 the body’s essential antioxidant.73 88 

Taurine has been shown to reduce lipid damage (forming of lipid peroxides) from peroxynitrite89 

 

V.   Compounds Related to Peroxynitrite Biochemistry

Magnesium levels should be ample. Deficiency is very common with toxic injury47 and this allows NMDA activation (excess NMDA increases the inflammatory vicious cycle of neural sensitization). Magnesium acts as a blocker of the NMDA nerve receptor, thus reducing nerve pain and its inflammation.75 Reducing NMDA activation helps reduce damaging peroxynitrite. 

 

 

http://www.chemicalinjury.net/html/neural_sensitization-pg_7.html 


Lane Simonian
Posted: Tuesday, October 30, 2012 9:15 PM
Joined: 12/12/2011
Posts: 4854


I like it when other people point to peroxynitrites as a prinicipal cause of Alzheimer's disease and point to phenolic compounds as both a means to protect against Alzheimer's disease and to treat it.  It makes me feel like I am on exactly the right path. 

 

Besides DNA damage, peroxynitrite elevations in the brain is linked to neurofibrillary tangles (5), and the neurotoxicity of beta-amyloid peptide (BAP). (6) The oxidative stress induced by peroxynitrite and other oxidative factors, is a key component to the disease process associated with Alzheimer’s disease. (7)

 

The role of ALA in buffering the neurotoxic effects of peroxynitrite is a recent revelation, yet there is plenty of similar evidence demonstrating the same benefits to other antioxidants-both from foods and nutraceuticals. Glutathione, the body’s primary antioxidant, counters peroxynitrite reactions, and protects against DNA single strand breaks. ( Carotenoids (lycopene, beta-carotene) and ascorbates (vit C as mineral ascorbates) are able to neutralize peroxynitrite oxidation. (9) Quercetin and EGCg from green tea, rutin, and resveratrol and cocoa have neuroprotective benefits including protection from peroxynitrite. (10, 11) Ellagic acid in strawberries, blueberries and raspberries are protective from oxidative and nitrative damage from peroxynitrite. (12) Grape Seed Polyphenols*** have also demonstrated in research to have peroxynitrite scavenging properties, (13) inhibition of beta amyloid plaque formation, and the protection from other oxidative stress reactants associated with beta amyloid toxicity on brain cells. (14, 15)

 

http://www.thealzheimerssolution.com/alpha-lipoic-protects-brain-cells-neurons-antioxidant-mechanisms-for-alzheimers-prevention/ 

 

It's just a matter of getting the best phenols (such as methoxyphenols) to the brain in great enough concentrations.  I am almost certain that the treatment of Alzheimer's disease is as simple as that. 

 

 


Lane Simonian
Posted: Tuesday, October 30, 2012 11:09 PM
Joined: 12/12/2011
Posts: 4854


This is kind of my dream.  One of these days after all the amyloid beta and tau drug therapies have largely failed, someone is going to say the real cause of this disease is peroxynitrites and that it can be treated with simple phenolic compounds.  They will say, "why didn't someone think of this before?" I will hit my head against the wall a couple of times and then I will go back to my old life. 
Iris L.
Posted: Monday, November 5, 2012 9:04 PM
Joined: 12/15/2011
Posts: 16705


I'm listening, Lane.  Thanks to you and onward for bringing this information about the phenolic compounds to our attention. 

Although I have a doctoral degree, I have a hard time following scientific data nowadays.  But I can follow your posts.

Iris L.