Increased levels of proinflammatory cytokines in the aged rat brain attenuate injury-induced cytokine response after excitotoxic damage

O. Campuzano, M. M. Castillo-Ruiz, Laia Acarin, B. Castellano, B. Gonzalez

Research output: Contribution to journalArticleResearchpeer-review

62 Citations (Scopus)

Abstract

In order to evaluate proinflammatory cytokine levels and their producing cell types in the control aged rat brain and after acute excitotoxic damage, both adult and aged male Wistar rats were injected with N-methyl-D-aspartate in the striatum. At different survival times between 6 hr and 7 days after lesioning, interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) were analyzed by enzymelinked immunosorbent assay and by double immunofluorescence of cryostat sections by using cell-specific markers. Basal cytokine expression was attributed to astrocytes and was increased in the normal aged brain showing region specificity: TNF-α and IL-6 displayed age-dependent higher levels in the aged cortex, and IL-1β and IL-6 in the aged striatum. After excitotoxic striatal damage, notable age-dependent differences in cytokine induction in the aged vs. the adult were seen. The adult injured striatum exhibited a rapid induction of all cytokines analyzed, but the aged injured striatum showed a weak induction of cytokine expression: IL-1β showed no injury-induced changes at any time, TNF-α presented a late induction at 5 days after lesioning, and IL-6 was only induced at 6 hr after lesioning. At both ages, in the lesion core, all cytokines were early expressed by neurons and astrocytes, and by microglia/macrophages later on. However, in the adjacent lesion border, cytokines were found in reactive astrocytes. This study highlights the particular inflammatory response of the aged brain and suggests an important role of increased basal levels of proinflammatory cytokines in the reduced ability to induce their expression after damage. © 2009 Wiley-Liss, Inc.
Original languageEnglish
Pages (from-to)2484-2497
JournalJournal of Neuroscience Research
Volume87
Issue number11
DOIs
Publication statusPublished - 15 Aug 2009

Keywords

  • Aging
  • Astrocyte
  • Cortex
  • Interleukin-1β
  • Interleukin-6
  • Microglia
  • Striatum
  • TNF-α

Fingerprint Dive into the research topics of 'Increased levels of proinflammatory cytokines in the aged rat brain attenuate injury-induced cytokine response after excitotoxic damage'. Together they form a unique fingerprint.

Cite this