Effects of the combination of melatonin and N-acetylcysteine on the inflammatory response in a rat model of cerebral ischemia.

Stroke is the second leading cause of death and long-term damage globally. Inflammation is a significant factor in the onset of ischemic stroke. This study investigated the simultaneous administration of melatonin and N-acetylcysteine (NAC) on inflammation in rat cerebral ischemia. First, 30 male Wistar rats were randomly divided into five groups (n = 6), including the sham group without ischemia, the ischemic group, and the ischemic groups treated with NAC, melatonin, and NAC + melatonin, respectively. To induce ischemia, a silicone-coated monofilament was placed from the common carotid artery towards the middle cerebral artery and stained for 60 min. The rats were treated by administering NAC (50 mg/kg), melatonin (5 mg/kg) and the combination of NAC + melatonin by intraperitoneal injection after ischemia induction. The animals were assessed for sensory-motor activity at 24 and 72 h. Following sacrifice, the rats' brain was dissected to estimate infarct volume after triphenyltetrazolium chloride (TTC) staining. Inflammatory parameters were then analyzed through gene expression analysis using reverse transcription quantitative polymerase chain reaction (RT-qPCR) for nuclear factor kappa B (NF-κB), tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), and nucleotide oligomerization domain (NOD)-like receptor family with pyrin domain 1 and 3 (NLRP1 and NLRP3). The results showed a significant decrease in mRNA expression of the target genes in the rats treated with NAC + melatonin compared to the ischemic group (p < 0.05). The group that received the combined treatment exhibited enhanced sensory-motor function and a reduced brain infarct volume compared to the other groups (p < 0.05). In summary, the combined use of NAC and melatonin has shown promise in enhancing neurobehavioral function and decreasing the volume of cerebral infarction by regulating the inflammatory signaling pathway.