EFFECTS OF NICOTINAMIDE ON MICROGLIAL RESPONSE IN JUVENILE RATS AFTER CONTROLLED CORTICAL IMPACT

Author

Aidan C. Smith, Southern Illinois University CarbondaleFollow

Date of Award

12-1-2017

Degree Name

Master of Arts

Department

Psychology

First Advisor

Hylin, Michael

Abstract

AN ABSTRACT OF THE THESIS OF AIDAN CHRISTIE SMITH, for the MASTER OF ARTS degree in PSYCHOLOGY, presented on OCTOBER 27th, 2017, at Southern Illinois University Carbondale. TITLE: EFFECTS OF NICOTINAMIDE ON MICROGLIAL RESPONSE IN JUVENILE RATS AFTER CONTROLLED CORTICAL IMPACT MAJOR PROFESSOR: Dr. Michael J. Hylin Traumatic brain injury (TBI) is a leading cause of death, cognitive and behavioral disability in children in industrialized nations. Preclinical trials of nicotinamide (NAM) treatment provide neuroprotection and reduced inflammatory responses in adult models of TBI. The primary goal of this study was to address the neuroprotective effects of NAM in the developing brain, specifically, the microglial response that occurs following injury. Animals received a bilateral craniotomy with a single cortical contusion injury over the parietal lobe and were treated with either 500mg/kg of nicotinamide or 0.9% saline via intraperitoneal injection. Animals received three injections, 15 minutes, 24 hours, and 48 hours after injury, and were sacrificed at 4 time points, 3 hours, 72 hours, 1 week, or 1 month following injury. Brains were then used for histological assessment for microglial activity. The results show that NAM attenuates the activation of microglia after CCI. Over the course of time, saline treated animals had a marked increase in microglia at 72 hours and remained elevated after 1 week. In NAM treated animals however, there was no significant increase in the number of microglia at any time point. It is suggested here that NAM has a great effect on the inflammatory response. Further studies are needed to examine NAM’s effects on behavior and functional recovery.