Rehabilitation Augments Hematoma Clearance and Attenuates Oxidative Injury and Ion Dyshomeostasis After Brain Hemorrhage

Abstract

Background and Purpose— We assessed the elemental and biochemical effects of rehabilitation after intracerebral hemorrhage, with emphasis on iron-mediated oxidative stress, using a novel multimodal biospectroscopic imaging approach. Methods— Collagenase-induced striatal hemorrhage was produced in rats that were randomized to enriched rehabilitation or control intervention starting on day 7. Animals were euthanized on day 14 or 21, a period of ongoing cell death. We used biospectroscopic imaging techniques to precisely determine elemental and molecular changes on day 14. Hemoglobin content was assessed with resonance Raman spectroscopy. X-ray fluorescence imaging mapped iron, chlorine, potassium, calcium, and zinc. Protein aggregation, a marker of oxidative stress, and the distribution of other macromolecules were assessed with Fourier transform infrared imaging. A second study estimated hematoma volume with a spectrophotometric assay at 21 days. Results— In the first experiment, rehabilitation reduced hematoma hemoglobin content ( P =0.004) and the amount of peri-hematoma iron ( P <0.001). Oxidative damage was highly localized at the hematoma/peri-hematoma border and was decreased by rehabilitation ( P =0.004). Lipid content in the peri-hematoma zone was increased by rehabilitation ( P =0.016). Rehabilitation reduced the size of calcium deposits ( P =0.040) and attenuated persistent dyshomeostasis of Cl − ( P <0.001) but not K + ( P =0.060). The second study confirmed that rehabilitation decreased hematoma volume ( P =0.024). Conclusions— Rehabilitation accelerated clearance of toxic blood components and decreased chronic oxidative stress. As well, rehabilitation attenuated persistent ion dyshomeostasis. These novel effects may underlie rehabilitation-induced neuroprotection and improved recovery of function. Pharmacotherapies targeting these mechanisms may further improve outcome.