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Betreff: Autism/Alzheimer's/heme/beta-amyloid plaques |
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Von: Dorothee Krien |
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Datum: Sun, 24 Jun 2007 23:47:07 +0100 |
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Dr. Boyd E.
Haley mentioned a new report "implying lack of heme was a major reason why
beta-amyloid plaques build up in the brains of Alzheimer's diseased
subjects". I've copied the abstract and pasted a blog and a news item on
Hami Atamna's findings on heme.
http://www.whale.to/v/haley.pdf
B.E.Haley and T. Small/Medical Vertitas 3(2006) 921 934
Interview with Dr Boyd E. Haley: Biomarkers supporting mercury toxidity as the
major exacerbator of neurological illness, recent evidence via the urinary
porphyrin tests
Boyd E. Haley PhD
and Teri Small
Professor of
Chemistry
AutismOne Radio
University of
Kentucky
1816 Houston Ave.
Email: behaley@uky.edu
Fullerton, CA 92833 USA
Email: tsmall@autismone.org
Website: www.autism.org
Abstract
In the recent past, several biological finds have supported the
hypothesis that early exposure of infants to Thimerosal was the major
exacerbation factor in the increase in autism-related disorders since the
advent of the mandated vaccine program. These initially included observations
of a genetic susceptibility impairing the execretion of mercury and the
increased retention of mercury by autistic children. This was followed by data
indicating that autistics have low levels of the natural compound glutathione
that is necessary for the bilary excretion of mercury, possibly explaining the
genetic susceptibility. Other observations clearly point out that various
biochemical processes are inhibited at exceptionally low nanomolar levels of
Thimerosal, including the killling of neurons in culture, the inhibition of
theenzyme that makes methyl-B12, the inhibition of phagocytosis
(the first step in the innate and acquired immune system), the inhibition of
nerve growth factor functional levels not cytotoxic, and the negative effect on
brain dendritic cells. It is also now quite clear from primate studies that
Thimerosal, or more correctly, the eythlmercury form Thimerosal delivers
mercury to the brain, and causes brain inorganic mercury levles higher than
equal levles of methylmercury.
Most recentlly, one study showed that 53% of autistic children had
aberrant porphyrin profiles similar ro mercury toxic individulas. Treatment of
these children with a mercury chelator brought these porphyrins back
towards normal levels indicating toxidity was the cause, not genetic
impairment. Porphyrin profiles are one of the most sensitive methods of
measuring toxic mercury exposures. Recently, in a major advance it was shown
that about 15% of the individuals on one population displayed a marked
sensitivity to mercury exposure in their porphyrin physiology, again supporting
the concept of a genetically susceptible population that is more
sensitive to mercury than the general population.
This observation on porphyrin aberrancies brings into
consideration other possible effects of mrecury toxidity that are secondary to
porphyrin depletion. Porphyrins are the precursors to heme synthesis. Heme is
the oxygen binding prosthetic group in hemoglobin and depletion of heme would
affect oxygen delivery to the mitochondria and decrease engery production. Also,
heme is a component of the electron transport system of mitochondria and a
prosthetic group in the P450 enzymes which are fundamental in the detox of the
body from many organic toxicants including pesticides and PCBs. Just recently,
a report was released implying that lack of heme was a major reason why
beta-amyloid plaques build up in the brains of Alzheimr's disesed subjects. It
seems that heme attaches to beta-amyloid helping it remain soluble and
excretable. Without adequate heme one of the major pathological diagnostic
hallmarks of Alzheimer's disease appears. It is well known that mercury rapidly
disrupts the normal polymerization of tubulin into microtubulin in brain tissue
and aberrant tubulin polymerization is a consistent factor observed in
Alzheimer's diseased brain. Therefore, it is the multiple inhibitions of
mercury that can cause various neurological and systemic problems and many of
these are secondary to the primary site of mercury binding.
Copyright 2006, Pearblossom Private School, INc,-Publsishing Division. All
rights reserved
Keywords: mercury toxidity, porphyring, heme, ubulin, autism
http://www.scienceblog.com/cms/alzheimers_study_first_to_explain_death_of_brain_cells_10211.html
Tue, 2006-03-14 14:41 — BJS
Researchers at Children's
Hospital & Research Center at Oakland (CHRCO) have published a new study
that is the first to explain how brain cells die in patients with Alzheimer's
Disease. This discovery is an important first step to helping researchers
devise ways to slow, prevent and eventually cure a disease that affects an
estimated 4.5 million Americans.
In a study published in the
February 28th issue of the Proceedings of the National Academy of Sciences,
lead scientist Hani Atamna, Ph.D., found that alterations in the production of
heme (a molecule that contains iron) may be the key to understanding why
excessive amyloid-beta is toxic to brain cells. Dr. Atamna had previously
discovered that Alzheimer's patients have abnormal amounts of heme in their
brains. In new research results, Atamna's team showed that amyloid-beta readily
binds with heme to form a compound that can be flushed from cells. When there
is insufficient heme or too much amyloid-beta, however, the amyloid-beta forms
large toxic "clumps" that the cell cannot dissolve and eliminate.
Though heme binding with
amyloid-beta can be beneficial, if too much heme is bound up with amyloid-beta,
there may be insufficient heme available for the cell to properly function. When
this happens, the cell's mitochondria, which are the tiny structures inside
brain cells that produce the energy the cells need to function, begin to decay.
Dr. Atamna refers to this phenomenon as a "functional heme
deficiency" because the cells are still forming heme, but it is trapped
within an amyloid-beta/heme compound.
When they examined the
heme/ amyloid-beta compound researchers in the Atamna laboratory were surprised
to discover it was a peroxidase--a type of enzyme that reacts harmfully with
biological materials essential for proper brain function such as serotonin and
L-DOPA. Dr. Atamna believes that the combination of functional heme deficiency,
which harms mitochondria needed to produce energy, together with the increase
in oxidative damage caused by the peroxidase, is what eventually kills the
cell.
"Until now, we didn't
understand all the factors that trigger Alzheimer's disease. The discovery of
the formation of amyloid-beta peroxidase provides a clear picture of why cells
die in the brain of Alzheimer's patients. Our next challenge is to develop
drugs that directly and selectively target the excessive peroxidase of
amyloid-beta, which could lead to the first significant therapy for Alzheimer's
disease."
From Children's Hospital Oakland
http://www.chori.org/Current_News/Archives/06_May_Atamna_PNAS_Alzheimers.html
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"Until
now, we didn't understand all the factors that trigger Alzheimer's disease. Our
next challenge is to develop drugs that could lead to the first significant
therapy for Alzheimer's disease." |
CHORI
scientist, Hani Atamna, PhD has just published a new study in
the February 28th issue of the Proceedings of the National Academy of
Sciences . The first study to explain how brain cells die in patients with
Alzheimer's Disease, Dr. Atamna's research could lead to a cure for Alzehimer's
disease.
The revolutionary study
found that alterations in the production of heme (a molecule that contains
iron) may be the key to understanding why excessive amyloid-beta is toxic to
brain cells. Dr. Atamna had previously discovered that Alzheimer's patients
have abnormal amounts of heme in their brains. In new research results,
Atamna's team showed that amyloid-beta readily binds with heme to form a
compound that can be flushed from cells. When there is insufficient heme or too
much amyloid-beta, however, the amyloid-beta forms large toxic
"clumps" that the cell cannot dissolve and eliminate.
Though heme binding with
amyloid-beta can be beneficial, if too much heme is bound up with amyloid-beta,
there may be insufficient heme available for the cell to properly function. When
this happens, the cell's mitochondria, which are the tiny structures inside
brain cells that produce the energy the cells need to function, begin to decay.
Dr. Atamna refers to this phenomenon as a "functional heme
deficiency" because the cells are still forming heme, but it is trapped
within an amyloid-beta/heme compound.
When they examined the
heme/ amyloid-beta compound researchers in the Atamna laboratory were surprised
to discover it was a peroxidase—a type of enzyme that reacts harmfully with
biological materials essential for proper brain function such as serotonin and
L-DOPA. Dr. Atamna believes that the combination of functional heme deficiency,
which harms mitochondria needed to produce energy, together with the increase
in oxidative damage caused by the peroxidase, is what eventually kills the
cell.
"The discovery of the formation of amyloid-beta peroxidase provides a
clear picture of why cells die in the brain of Alzheimer's patients," says
Dr. Atamna. "Our next challenge is to develop drugs that directly and
selectively target the excessive peroxidase of amyloid-beta, which could lead
to the first significant therapy for Alzheimer's disease."
http://www.news-medical.net/?id=16677
Study explains how brain
cells die in patients with Alzheimer's Disease
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Medical
Studies/Trials |
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Published:
Wednesday, 15-Mar-2006 |
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See also
Boyd Haley's talk: Iatrogenic Death and Disease Via Acute and Chronic Mercury
Poisoning
http://www.toxicteeth.org/Mercury-poisoning-2004.pdf