Enhanced glial activation and expression of specific CNS inflammation-related molecules in aged versus young rats following cortical stab injury.

Aging is associated with increased glial responsiveness that may enhance the brain's susceptibility to injury and disease. To determine whether unique age-related molecular responses occur in brain injury, we assessed mRNA levels of representative central nervous system (CNS) inflammation-related molecules in young (3 months) and aged (36 months) Fisher 344/Brown Norwegian F1 hybrid rats following cortical stab. Enhanced glial activation in older animals was accompanied by increased expression of a subset of inflammation-related mRNAs, including IL-1beta, TNFalpha, IL-6, ICAM-1, inducible nitric oxide synthase (iNOS), metalloproteinase-9 (MMP-9), and complement 3alpha-chain 1 (C3alpha1). Recognition of these age-specific differences may guide development of novel treatment regimes for older individuals.