Neuroprotective effects of Hemocoagulase Agkistrodon on experimental traumatic brain injury

Traumatic brain injury (TBI) is the major cause of disability and mortality among young people and is associated with neurodegenerative diseases. However, the available clinical options have limited effectiveness. Here, we investigated the neuroprotective effect of Hemocoagulase Agkistrodon (HCA), a thrombin-like enzyme (TLE) isolated and purified from snake venom. Rats subjected to experimental TBI were administered a single dose of HCA or vehicle 10 min after injury. Neurological function was assessed with modified neurological severity score (mNSS). Brain edema were evaluated by measuring brain water content. Levels of hemoglobin and inflammatory cytokines were detected by Enzyme-linked immunosorbent assay (ELISA). In addition, assays including Evans blue extravasation, Western blot analysis and immunofluorescence staining were utilized to determined blood-brain barrier (BBB) integrity. Our results showed that HCA treatment ameliorated neurological deficits (p < 0.01), alleviated brain edema (p < 0.01) and hemorrhage (p < 0.01), decreased the production of the proinflammatory cytokines IL-1β (p < 0.01), TNF-α (p < 0.01) and IL-6 (p < 0.05), and increased the anti-inflammatory cytokine IL-10 at the contusion site (p < 0.01). Moreover, HCA administration reduced BBB disruption by regulating expression of tight junction proteins, including ZO-1, occludin and claudin-5 (ps < 0.01). Together, our results demonstrate that HCA might have therapeutic efficacy in acute TBI, suggesting a potential clinical application for mitigating the neuropathological damage associated with TBI.