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Science marches on!

Kathy

Well-known member
This group, which is associated with FATEPRIDE, are continuing to examine the relationship between copper deficiency and neurodegenerative brain disorders. It is very good to see that this study followed animals from their infancy to the young adult stage. The brain does not finish development until this "young adult stage". With humans, it is known that the brain is not finished full development until approximately 25 years of age.

Copper deficiency showed vacuolation of the brain.

Neuropathol Appl Neurobiol. 2007 Apr;33(2):212-25.

Copper deficiency elicits glial and neuronal response typical of neurodegenerative disorders.

Zucconi GG, Cipriani S, Scattoni R, Balgkouranidou I, Hawkins DP, Ragnarsdottir KV.
Department of Cell and Environmental Biology, University of Perugia, Perugia, Italy.

Dysregulation of copper homeostasis has been associated with neurodegenerative diseases including Alzheimer's disease, amyotrophic lateral sclerosis (ALS) and prion diseases. The investigation of the role of abnormal copper level in the development of neuropathological damage is essential for the understanding of pathogenetic mechanisms of these neurodegenerative disorders. Using a mouse model of perinatally induced copper deficiency, the present study analysed the response of neuronal and glial cells to copper deficiency from infancy to young adult age. In mice born and maintained after weaning on copper-deficient diet, copper measurements indicated that at 6-8 weeks the copper levels in the brain were decreased by about 80% with respect to controls. In the brain of copper-deficient mice, microglial and astrocytic activation was observed, mostly in the cerebral cortex and thalamus. In addition, small vacuolated globoid cells confined to the subgranular zone of the dentate gyrus were found in the third postnatal week, and larger vacuolar profiles, identified as neuronal vacuoles, were observed in layer V of the cortex after the fourth week. The spatial distribution and temporal onset of vacuolation appeared to be unrelated to those of activated microglia and astrocytes. Nitrotyrosine-positivity was found to reflect the distribution of vacuoles in the cortex. The specific histopathological features here reported, as well as the severity of neurological deficits observed in this murine model of copper deficiency, strongly suggest that some hallmarks of neurodegenerative disorders could be mediated by multifactorial pathogenetic mechanisms that include copper dysregulation.

PMID: 17359362


2005 Ragnarsdottir K.V. and Hawkins D.P.
Bioavailable copper and manganese in soils from Iceland and their relationship with scrapie occurrence in sheep.
Journal of Geochemical Exploration, 88, 228-234.

The bioavailability of trace metals can be directly linked with many common animal and human diseases. It is easier to correlate regional geochemical trends with disease distribution in the developing world because local populations and animals live from the land. In the western world, humans tend to live from the global food market whereas animals graze on the land. Recent biochemical studies have shown that the prion protein needs copper to keep its structure. If copper is not available, the prion protein can take up manganese and unfold. Preliminary results for trace metals in soil samples from scrapie-affected areas in Iceland show that bioavailable manganese manganese (easily reducible and exchangeable Mn) is very high whereas soluble copper and free copper are very low.

link: http://mycorrhiza.ag.utk.edu/latest/latest06/06_3ragna1.htm
link: http://geochemistry.gly.bris.ac.uk/publications/publications.html
 

Kathy

Well-known member
Some of Dr. Ragnarsdottir's other work, on OPs.

Environmental and Health Effects of Organophosphate Pesticides

K. Vala Ragnarsdottir ([email protected])
Department of Earth Sciences, University of Bristol, Bristol BS8 1RJ, U.K.
At present there are hundreds of pesticide approved for use globally. For example about 450 active ingredients are approved for use in the U.K. alone. At the present time organophosphates (OPs) are the most widely used pesticides in the world. Recent estimates suggest that pesticides account for more than 20,000 fatalities yearly, and that most of these will have occurred in developing countries. The effects of these pesticides is, however, not only fatal. Organophosphate (OP) pesticides are neurotoxins which act on the nervous systems of pests by inhibiting the breakdown of the neurotransmitter acetylcholine, a key substance involved with transmission of nerve impulses; this leads to death and a multitude of human illnesses . This presentation will focus primarily on organophosphate pesticide (OPs) behaviour in the environment and their toxicity because of recent suggestions that OPs may play a role in the development of BSE and human diseases such as CJD, Gulf War Syndrome, farmers flu, multiple chemical sensitivity, immune dysfunction, cancerous lymphomas, induced hypothermia, polyneuropathy, birth defects, mental retardation, chronic neurological sequelae, systemic illness, sleep disturbance, skin disease, and eye injury. Once OPs are in the environment their breakdown is considered to be "fast" (on the order of days) and therefore they are termed "safe". The primary physicochemical processes which retard and break down OPs are adsorption, biodegradation and hydrolysis. However, the breakdown of OPs is very much dependent on the environmental conditions. If the soil is clay or organic rich, the OPs adsorb to the surface of soil particles which retards their transport. This adsorption, however, also inhibits the biodegradation of the chemicals so that OPs can persist in soil environments for 10ths of years. Once the OPs reach the groundwater or surface waters, their solubility is relatively high (up to 100s of thousands of ppm), compared to drinking water limits of 0.1 ppb. In water the primary transformation process is hydrolysis, which is pH and temperature dependent. For example quoted half lives for OPs are those for laboratory conditions (pH 7, 25°C). But under typical N-European groundwaters the pH often is 6 and the temperature as low as 5°C. Under those conditions the half life which is quoted as 10 days in the literature is prolonged to one year. Finally, while drinking water limits are 0.1 ppb, the maximum acceptable concentrations in fruit and vegetables are around 10 ppm. Therefore, the population of Europe consumes over 90% of their pesticide intake via food. Bearing in mind the severe illnesses discussed above, is it not time to reconsider the use of these toxic substances on our food crops; are we poisoning our children when we present them with a balanced meal?
 
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