Acute Nicotine Exposure Evokes Spinal Cord Cell Death in an Ex-vivo Traumatic Spinal Cord Injury Model (S26.006)

Objective: Evaluate the relationship between nicotine and traumatic spinal cord injuries (SCI). Background: Traumatic SCI can lead to irreversible neurological damage. Nicotine, at the tissue level, has been associated with increased necrosis of organic tissues, likely because of the vasoconstriction and reduced local perfusion caused by this substance. Few studies have explored this effects in SCI. Design/Methods: An ex-vivo 3D culture system of spinal tissue from Wistar rats subjected to nicotine exposure was employed. The excised spinal cord tissue was transferred to culture plates and divided into four groups: control (n=5), nicotine (n=5), SCI (n=5), and nicotine plus SCI (n=5). Groups nicotine and nicotine plus SCI were exposed to nicotine after incubation (10 mM for three days, representing acute exposure). On the seventh day, groups SCI and nicotine plus SCI were subjected to mechanical compression via impact from a height of 25 mm with a 0.5 g weight at the center of the spinal section. Tissue nicotine-related alterations were assessed through morphology, molecular characteristics, cell viability and survival. Lactate dehydrogenase (LDH) levels were measured, and MTT assays, DAPI staining, and Live/Dead cell assays were conducted. Results: Tissues exposed to nicotine and subjected to SCI exhibited reduced cell viability and higher LDH levels compared to other groups. The Live/Dead cell assay revealed statistically significant higher cell death in group nicotine plus SCI. Given that SCI imposes a limiting condition and nicotine is a known vasoconstrictive agent, both factors were found to impede the tissue recovery process. Conclusions: Nicotine exposure was found to compromise cell viability and survival in injured spinal cord tissue. As nicotine is widely consumed worldwide and SCI is a potentially debilitating condition, it is essential to establish the relationship between nicotine exposure and traumatic SCI to highlight the adverse impact of nicotine on the prognosis of SCI patients. Disclaimer: Abstracts were not reviewed by Neurology® and do not reflect the views of Neurology® editors or staff. Disclosure: Miss Matté Dagostini has nothing to disclose. Miss Nesello has nothing to disclose. Mr. Einsfeld Britz has nothing to disclose. Dr. NICOLETTI has nothing to disclose. Dr. Falavigna has nothing to disclose.