Genetic Deletion of Haptoglobin Ameliorates Intracerebral Hemorrhage-induced Brain Damage

Background: The presence of extracorpuscular hemoglobin (Hb) exacerbates brain damage following intracerebral hemorrhage (ICH). Systemically, haptoglobin (Hp) is an acute phase glycoprotein that reduces brain injury by binding to extracellular Hb, which stabilizes the protein and prevents further toxic reactions. However, the properties of Hp within the brain during ICH are not well understood. This study aims to investigate the acute and chronic effects of haptoglobin deletion following ICH and the possibility that age influences the recovery outcomes. Methods: The ICH was induced in young and older aged (WT) controls and Hp-/- C57BL/6 mice using the autologous whole blood and collagenase injection models. Behavioral assessments of neurological deficit scoring, open field locomotor activity, and rotarod were conducted to investigate functional outcomes at 1d, 2d, 3d, 4d, 7d, and 10d. Various anatomical outcomes were measured through the staining for specific biomarkers following animal sacrifice at 3d an...