Ascorbic acid-containing compound efficacy in ischemic brain damage

Abstract

Introduction: Ischemic brain injury remains one of the main causes of disability and mortality worldwide. Protection of cellular population, depriving from oxygen supply and nutrients, is of extreme importance for further both clinical and health outcomes of timely implemented intravascular intervention. The aim: to assess anti-ischemic activity of 3-hydroxypyridine ascorbate in the in vitro and in vivo models of brain cell and tissue response to ischemia and reoxygenation. Materials and Methods: 3-hydroxypyridine ascorbate (laboratory code 3-EA) was assessed as chemical substance (purity 99.8%) diluted in sterile phosphate-buffered saline. Intracellular Ca2+ response to glutamate excitotoxicity (GluTox), ischemia and reoxygenation as well as cellular viability was evaluated on NMRI murine fresh cortical neuro-glial cell culture incubated with 2-EA by registering intracellular Fura-2 and propidium iodide fluorescence respectively. Expression of apoptosis regulating genes BCL-2, STAT3, SOCS3, inflammation regulating genes TRAIL, MLKL, Cas-1, Cas-3, IL-1β и TNFα, and genes MAO-A and MAO-B was determined by real-time PCR. The substance neuroprotection was studied in male Sprague-Dawley rats with intraluminal middle cerebral artery (MCA) occlusion/reperfusion treated with 18 mg/kg of 2-EA along with neurological deficiency evaluation and morphological assessment of brain sections. Results: Preincubation of cortical cells with 10-100 μM of 3-EA leads to inhibition of [Ca2+]i in cytosol of neurons and astrocytes under GluTox and oxygen-glucose deprivation (OGD) conditions. Reducing [Ca2+]i inhibits necrotic cell death in an acute experiment. Incubation of cerebral cortex cells with 3-EA leads to an overexpression of anti-apoptotic genes BCL-2, STAT3, SOCS3, along with downregulation of genes TRAIL, MLKL, Cas-1, Cas-3, IL-1β and TNFα. Intraperitoneal administration of 3-EA reduces the volume of necrotic areas, perinecrotic edema, cell damage, and neurological deficits in rats with MCA occlusion. Conclusion: 3-EA dose-dependently suppresses the death of cerebral cortex cells under the excitotoxic effects of glutamate and ischemia/reoxygenation. Cell-protective effect of 3-EA involves changes in the basal and ischemia/reoxygenation-induced expression of genes encoding anti-apoptotic proteins and oxidative status proteins, which leads to inhibition of the late irreversible stages of apoptosis. A course administration of 3-hydroxypyridine ascorbate at a dose of 18 mg/kg per day reduces the severity of damage both by preserving the population of neurons in the penumbra zone and by limiting the local stress response.