aProgramDirector et al, Vitamins

[Doowai]

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http://forums.studentdoctor.net/showthread.php?t=595765&highlight=vitamins This was another thread on the topic, instead of resurrecting I want to refer to it and move on, drawing on some abstracts and papers I have been reading as of late. I don't want to resurrect it as the main idea was what vitamins to take, - and essentially your opinion was vitamin pills were a waste of money if a person eats the standard American diet. I just want to play around and see if I can convince you otherwise....

What do you think of drawing a conclusion regarding B vitamins (Folate, B12) in the prevention and treatment of Alzheimer's?
3 studies - and one synthetic idea that might be drawn is that B vitamins can potentially rescue from memory deficits and prevent the development of AD. Valid or crap in your opinion?

1) .Am J Pathol... 2009 Mar 5. .
.Hyperhomocysteinemia Increases {beta}-Amyloid by Enhancing Expression of {gamma}-Secretase and Phosphorylation of Amyloid Precursor Protein in Rat Brain..
.Zhang CE.., ..Wei W.., ..Liu YH.., ..Peng JH.., ..Tian Q.., ..Liu GP.., ..Zhang Y.., ..Wang JZ....
.From the Department of Pathophysiology, Key Laboratory of Neurological Disease of Education Committee of China, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China..
.Hyperhomocysteinemia and beta-amyloid (Abeta) overproduction are critical etiological and pathological factors in Alzheimer disease, respectively; however, the intrinsic link between them is still missing. Here, we found that Abeta levels increased and amyloid precursor protein (APP) levels simultaneously decreased in hyperhomocysteinemic rats after a 2-week induction by vena caudalis injection of homocysteine. Concurrently, both the mRNA and protein levels of presenilin-1, a component of gamma-secretase, were elevated, whereas the expression levels of beta-secretase and presenilin-2 were not altered. We also observed that levels of phosphorylated APP at threonine-668, a crucial site facilitating the amyloidogenic cleavage of APP, increased in rats with hyperhomocysteinemia, although the phosphorylation per se did not increase the binding capacity of pT668-APP to the secretases. The enhanced phosphorylation of APP in these rats was not relevant to either c-Jun N-terminal kinase or cyclin-dependent kinase-5. A prominent spatial memory deficit was detected in rats with hyperhomocysteinemia. Simultaneous supplementation of folate and vitamin-B12 attenuated the hyperhomocysteinemia-induced abnormal processing of APP and improved memory. Our data revealed that hyperhomocysteinemia could increase Abeta production through the enhanced expression of gamma-secretase and APP phosphorylation, causing memory deficits that could be rescued by folate and vitamin-B12 treatment in these rats. It is suggested that hyperhomocysteinemia may serve as an upstream factor for increased Abeta production as seen in patients with Alzheimer disease..
.2 ) Clin Chem Lab Med... 2007;45(2):136-42. .
.Association of vitamin B12, folate and homocysteine with functional and pathological characteristics of the elderly in a mountainous village in Sicily..
.Spada RS.., ..Stella G.., ..Calabrese S.., ..Bosco P.., ..Anello G.., ..Guéant-Rodriguez RM.., ..Romano A.., ..Benamghar L.., ..Fontaine T.., ..Guéant JL....
.Oasi Institute for Research on Mental ******ation and Brain Aging (IRCCS), Troina (EN), Italy. [email protected].
.BACKGROUND: Homocysteine is associated with age, folate and vitamin B(12). Our study investigated the functional and clinical characteristics of the elderly (aged 60-85 years) of San Teodoro, a village in Central Sicily, and evaluated associations with vitamin B(12), folate and homocysteine. METHODS: Subjects (n=280) were examined after door-to-door recruitment using interview, physician examination and laboratory tests. RESULTS: A total of 19.3% of the population had a low blood level of folate (<7 nmol/L) and 3.2% had low vitamin B(12) concentration (<100 pmol/L). The level of dependency, determined by the Barthel index, influenced homocysteine blood levels (p<0.0001), independent of age (p<0.0001), folate (p=0.0028) and vitamin B(12) (p=0.0165). Homocysteine was significantly associated with stroke (p=0.0027) and peripheral arterial vascular disease (p=0.0001), but not with myocardial infarction, angina pectoris, venous thrombosis or cancer. Vitamin B(12) was lower in myocardial infarction and higher in diabetes and venous thrombosis compared to the other diseases. CONCLUSIONS: The prevalence of deficits in folate and vitamin B(12) was paradoxically high in the mountainous northeastern area of Sicily. Our study also underlines the association of homocysteine with dependency of the elderly and with stroke and peripheral arteriopathy..
.3) J Neurol Sci... 2009 Mar 3.
.Prevalence of dementia in mountainous village of Sicily..
.Spada RS.., ..Stella G.., ..Calabrese S.., ..Bosco P.., ..Anello G.., ..Guéant-Rodriguez RM.., ..Romano A.., ..Benamghar L.., ..Guéant JL....
."Oasi" Institute for Research on Mental ******ation an Brain Aging (I.R.C.C.S.), Troina (EN), Italy..
.The progressive and rapid aging of population is the demographic characteristic in the Western countries. This rapid process of aging is causing an increasing burden on the social and health-care services. In this context, the precise knowledge of the environmental, socio-economical and clinical characteristics of the elderly population is mandatory to find the correct strategies to achieve the successful aging. Our study aimed to investigate the functional and clinical characteristics of the elderly (aged 60 to 85 years) of San Teodoro (1500 inhabitants), a rural village of Central Sicily, in particularly considering the dementia prevalence. In 2005, all the elderly between 60 and 85 years old were invited to participate to the study. The list of the potential participants was obtained from the Registry office of the municipality. The final number of the eligible subjects was 374. Rate of participation was 74.9% (280 subjects, 120 M and 160 F). The study was conducted door-to-door. Dementia prevalence was 7.1% (20 subjects, 8 M and 12 F), with 60% Alzheimer's disease and 15% vascular dementia, slightly higher than that of the European countries (6%). The high prevalence of hypertension (80.3%) and the low education level, two important risk factors for dementia, could explain in part the difference observed..

 

[NotAProgDirector]

Several small (and large) studies have looked at this. To date, no convincing evidence that B vitamin supplementation prevents, stabilizes, or treats dementia. The usual theory is homocysteine related -- i.e. that B vitamin deficiency causes elevated homocysteine levels (mostly due to folate deficiency)

Small studies:

This study in the NEJM looked at 270+ elders with elevated homocysteine levels. Folate supplementation decreased homocysteine levels but no change in cognition was noted. Participants were NOT demented at baseline.

This study looked at 89 patients with dementia, randomized to usual treatment (anticholenesterase inh) +/- vitamins. Again, decreased homocysteine, no change in cognition nor ADL's. Only 26 weeks of followup.

Large studies: There are several large studies looking at B vitamins and heart disease. To date, these studies have failed to demonstrate any cardiovascular ebenfit of B vitamins (although not all of the studies have reported, and it's possible that given a larger sample size / meta analysis a small benefit will be found). Supposedly we will also get dementia data from this, but to my knwoledge it has not been published.