Alzheimer's disease linked to high blood sugar; green tea slows its progression

Researchers have uncovered a unique connection between diabetes and Alzheimer's disease, providing further evidence that elevated blood sugar may contribute to the memory-robbing disease. In tests done on mice, scientists at Washington University School of Medicine in St Louis found that elevated glucose in the blood can rapidly increase levels of amyloid beta, a key component of brain plaque in Alzheimer's patients. The build-up of plaque is thought to be an early driver of the complex set of changes that Alzheimer's causes in the brain. In young mice without amyloid brain plaque, doubling glucose levels in the blood increased amyloid beta levels in the brain by 20 per cent. When the experiment was repeated in older mice that had developed brain plaque, amyloid beta levels rose by 40 per cent. The research was published last week in The Journal of Clinical Investigation.

Consuming a compound found in green tea, combined with voluntary exercise, slows the progression of Alzheimer's disease in mice and may reverse its effects, finds a new University of Missouri study. Mice that showed Alzheimer's symptoms - such as amyloid plaque deposits in the brain and behaviour deficits - were first put through a series of memory and cognition tests. The mice were then fed the green tea extract, epigallocatechin-3-gallate (EGCG), and given access to exercise wheels. The tests were done again and the researchers found remarkable improvements in the cognitive function and retention in the affected mice. There was also a decrease in amyloid-beta peptide levels - the precursor to amyloid plaques - in the brains of the affected mice.

Exposure to outdoor air pollution during the first year of life increases the risk of developing allergies to food, mould, pets and pests, according to new research from a large-scale, long-term Canadian infant study. Published in Environmental Health Perspectives, the study found no link, however, between mothers exposed to air pollution during pregnancy and allergy risk in their children. The researchers used data from 2,477 children and assessed the children with skin allergy testing at around one year of age. Of the participants, 16 per cent of infants were sensitive to at least one of 10 tested allergens, which included cat, dog, dust mites, cockroach, fungus, milk, egg, soy and peanuts. Children who live with furry pets and no attached garage were more likely to have no sensitivity to allergens. Children who attended daycare or had older siblings in the household were less likely to develop allergic sensitisation, suggesting that exposure to other children can be protective.