Protective effects of indomethacin-loaded nanocapsules against oxygen-glucose deprivation in organotypic hippocampal slice cultures: Involvement of neuroinflammation

Targeted treatment of diseases of the central nervous system remains problematic due to the complex pathogenesis of these disorders and the difficulty in drug delivery. Here we investigate the neuroprotective effect of indomethacin-loaded nanocapsules (IndOH-NC) in an in vitro model of ischemia. For this purpose we used organotypic hippocampal cultures exposed to oxygen-glucose deprivation (OGD). When the cultures were exposed to 60 min of OGD, 54.5 ± 14.7% of the total area of the hippocampal slices was labeled with propidium iodide. On the other hand, when the cultures were treated with 50 or 100 μM of IndOH-NC the cell death was significantly reduced to 31 ± 7% (P < 0.05) and 20 ± 4% (P < 0.001), respectively. The treatment with IndOH-NC markedly inhibited the levels of the pro-inflammatory cytokines IL-1β, IL-6 and TNF-α levels even 48 h after OGD. Immunoblotting revealed that treatment with 100 μM of IndOH-NC was able to significantly reduce to the levels of control cultures the levels of ERK1/2 and JNK phosphorylation, as well as iNOS activation. Additionally, IndOH-NC prevented glial activation induced by OGD, as evidenced by a decrease of GFAP immunocontent and Isolectin B4 reactivity. Our results clearly demonstrate that IndOH-NC might represent a promising pharmaceutical neuroprotective formulation for cerebral ischemia, most probably by inhibiting the inflammatory cascades.