Aluminium and Alzheimers'!!!

Sandeep Tripathi et al from CDRI, Lucknow are publishing their research in Brain Research Journal. The topic is controversial "Aluminium and Alzheimers disease" related. Issue was upheld when aluminium was detected in neurofibrillary tangles (DP Perl et al, Science, 1980)and a study suggested a geographical correlation between aluminium and alzheimers in the journal Lancet (C N Martyn et al, Lancet 1989). And so the story goes on. Aluminium is used in water cleaning, utensils etc and hence a potential for a toxic metal to induce neurological changes exists.

According to authors, aluminium ingestion (100mg/Kg) caused reduction in body weight, brain weight more evident in aged male wistar rats. Treated aged rats had less relearning index in Y-maze test compared to untreated or even young treated ones!

Aged as well as young treated rats had less protein, more lipid, more conjugated dienes, more lipid peroxides and hydroperoxides, more lipofuscin compared to untreated age-matched controls. They also had significant less levels of catalase, superoxide dismutase, glutathion reduced as well as peroxidase along with increased levels of Iron, decreased Selenium and Copper.

n=12 in each group (Young control and treated=~6 months, Aged control and treated=~24 months). Its not not clear to me atlest whether they gave 100mg/kg AlCl3 mixed with 1% gum acacia for 90days to treated group.

Overall, this paper suggests that aluminium has age related effects of inducing oxidative stress and causes accumulation of lipofuscin in frontal cortex of wistar rats.

I just want to comment that aluminium concentration used does seem to be too high.
Reiko Matsuda et al ( Journal of the Food Hygienic Society of Japan(2001)) suggest daily dietary intake to be 1.8 to 8.4 mg..we dont know whats the scenario in India).

Ciba Foundation Symposium 169 - Aluminium in Biology and Medicine book excert is given below. Author is J L Greger

Aluminium in the food supply comes from natural sources including water, food additives, and contamination by aluminium utensils and containers. Most unprocessed foods, except for certain herbs and tea leaves, contain low (<5 µg Al/g) levels of aluminium. Thus most adults consume 1-10 mg aluminium daily from natural sources. Cooking in aluminium containers often results in statistically significant, but not practically important, increases in the aluminium content of foods. Intake of aluminium from food additives varies greatly (0 to 95 mg Al daily) among residents in North America, with the median intake for adults being about 24 mg daily. Generally, the intake of aluminium from foods is less than 1% of that consumed by individuals using aluminium-containing pharmaceuticals. Currently the real scientific question is not the amount of aluminium in foods but the availability of the aluminium in foods and the sensitivity of some population groups to aluminium. Several dietary factors, including citrate, may affect the absorption of aluminium. Aluminium contamination of soy-based formulae when fed to premature infants with impaired kidney function and aluminium contamination of components of parenteral solutions (i.e. albumin, calcium and phosphorus salts) are of concern.

This "metal ions" causing problems theory is gonna stay untill we pinpoint the exact cause of Alzheimers disease and produce a perfect model of it (apart from current so called Alzheimer models..are majorly just models of amyloidosis kind of disorders!!)

Long way to go in this but this atleast lets us know of ill effects of Aluminium.

Influence of age on aluminum induced lipid peroxidation and neurolipofuscin in frontal cortex of rat brain: A behavioral, biochemical and ultrastructural study

Brain Research, Article in Press,
doi:10.1016/j.brainres.2008.11.060

Sandeep Tripathi,Abbas Ali Mahdi, Akbar Nawab, Ramesh Chander,Mahdi Hasan,Mohammad Shakil Siddiqui,Farzana Mahdi,Kalyan Mitra and Virendra Kumar Bajpai

Department of Biochemistry, King George’s Medical University
Department of Anatomy, King George’s Medical University
Department of Biochemistry, Era’s Lucknow Medical College
Electron Microscopy Division, Central Drug Research Institute, Lucknow, India 226003

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Another study in the Brain Research Journal by Kumar V et al (PGIMER, Chandigarh) reports impairment in mitochondrial energy metabolism in wistar rats receving 10mg/kg body weight aluminium for 12 weeks. They also found decreased levels of SOD and Glutathion as well as increased ROS.

Intake is still high compared to human estimates (10mg/60Kg=0.16mg/Kg)

Impairment of mitochondrial energy metabolism in different regions of rat brain following chronic exposure to aluminium.

Kumar V, Bal A, Gill KD.
Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, 160 012, India.

Brain Res. 2008 Sep 26;1232:94-103. Epub 2008 Jul 16