New evidence points to brain trauma as an environmental risk factor for Alzheimer disease (AD). Researchers at the University of Pennsylvania School of Medicine have shown that multiple, mild head injuries accelerate ß-amyloid plaque deposition, believed to be an etiologic factor in AD (K. Urya et al., "Repetitive mild brain trauma accelerates Aß deposition, lipid peroxidation and cognitive impairment in a transgenic mouse model of Alzheimer amyloidosis," Journal of Neuroscience, 22:446-54, Jan. 15, 2002.) Researchers anesthetized wild-type mice and transgenics (Tg2576) predisposed to develop AD-like amyloid plaques and then tapped the animals' heads once or twice. Compared to mice tapped once and wild types, transgenic animals tapped twice scored worse in water maze tests. Amyloidosis was greatly accelerated in all tapped transgenics, and isoprostanes, produced by lipid peroxidation, increased in all struck mice. John Q. Trojanowski, codirector for the University of Pennsylvania's Center for Neurodegenerative Disease Research, says,...

Interested in reading more?

Magaizne Cover

Become a Member of

Receive full access to digital editions of The Scientist, as well as TS Digest, feature stories, more than 35 years of archives, and much more!