Prolonged exposure to microwave radiation produced the stress protein, even though there appeared to be no noticeable heating.

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In previous experiments, De Pomerai's team studied worms that were genetically modified to generate a heat-stress protein when exposed to stresses other than heat.

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The protein could also increase oxidative stress, which it is believed damages cells by creating free radicals which then stimulate the production of AGEs.

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He has conducted studies on living neurons which suggest that the tau protein is produced in response to oxidative stress, thus lending support to the protective hypothesis.

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And earlier this year, a study found that when mice are subjected to stress over a period of time, they have more phosphorylated tau protein deposits in their brains (see this Scientific American blog for a nice synopsis).

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