Tumor necrosis factor-á (TNF-á) is one of the key players in stroke progression and can interfere with brain functioning. We previously documented an impairment of experience-dependent plasticity in the cortex neighboring the stroke-induced lesion, which was accompanied with an upregulation of Tnf-á level in the brain of ischemic mice 1 week after the stroke. Because TNF receptor 1 (TnfR1) signaling is believed to be a major mediator of the cytotoxicity of Tnf-á through activation of caspases, we used an anti-inflammatory intervention aimed at Tnf-á R1 pathway, in order to try to attenuate the detrimental effect of post-stroke inflammation, and investigated if this will be effective in protecting plasticity in the infarct proximity. Aged mice (12-14 months) were subjected to the photothrombotic stroke localized near somatosensory cortex, and immediately after ischemia sensory deprivation was introduced to induce plasticity. Soluble TNF-á R1 (sTNF-á R1), which competed for TNF-á with receptors localized in the brain, was delivered chronically directly into the brain tissue for the whole period of deprivation using ALZET Micro-Osmotic pumps. We have shown that such approach undertaken simultaneously with the stroke reduced the level of TNF-á in the peri-ischemic tissue and was successful in preserving the post-stroke deprivation-induced brain plasticity.
Animals Binding, Competitive