Ibuprofen for neuroprotection after cerebral ischemia

Abstract

Objective: Ibuprofen has been shown to reduce cerebral ischemic injury, such as may occur after deep hypothermic circulatory arrest. We investigated whether ibuprofen has direct protective effects against excitotoxic neuronal injury, as may be seen after cerebral ischemia, by using a cell culture model.

Methods: Mixed cortical cultures containing neuronal and glial cells were prepared from fetal mice at 13 to 15 days gestation, plated on a layer of confluent astrocytes from 1- to 3-day-old postnatal pups. Near-pure neuronal cultures containing less than 5% astrocytes were obtained from mice of the same gestational stage. Slowly triggered excitotoxic injury was induced at 37 degrees C by 24-hour exposure to 12.5 micromol/L N-methyl-D-aspartate or 50 micromol/L kainate. Neuronal death was quantified by release of lactate dehydrogenase from damaged cells. Data were analyzed using 1-way analysis of variance with Tukey post hoc multiple comparisons.

Results: In mixed cultures, ibuprofen concentrations of 25 microg/mL, 50 microg/mL, and 100 microg/mL all significantly reduced N-methyl-D-aspartate-induced neuronal cell death from 74.5% to 56.1%, 38.7%, and 12.3%, respectively, revealing a strong dose response (P < .001). In near-pure cultures, ibuprofen at a concentration of 25 microg/mL failed to protect neurons, indicating that the neuroprotective effects of ibuprofen require interaction with glial cells. Furthermore, ibuprofen at 100 microg/mL was not protective against neuronal cell death induced by kainate excitotoxicity in near-pure culture but was effective in mixed cultures.

Conclusion: Ibuprofen provides neuroprotection through glial cells against excitotoxic neuronal injury caused by glutamatergic excitotoxicity after cerebral ischemia as demonstrated by reduced neuronal cell death in mixed cell cultures. Further studies are needed to evaluate the potential of ibuprofen to reduce neurologic injury in patients experiencing an hypoxic/ischemic insult.