Melatonin ratlarda post-travmatik iskemik beyin hasarını önlemektedir

Öz

Amaç: Beyin travması, dünyadaki ölümlerin ve uzun süreli sakatlığın önde gelen nedenleri arasındadır. Çalışmalar, serebral iskeminin travmatik beyin hasarında (TBH) sekonder nöronal hasarın önemli bir mekanizması olduğunu göstermiştir. Bilimsel araştırmalar, melatoninin travma sonrası beyin üzerinde koruyucu bir etkiye sahip olduğunu göstermiştir. Ayrıca melatoninin birçok serebral patofizyolojik süreçte beyin iskemik beyin hasarını hafiflettiği gösterilmiştir. Bununla birlikte, melatoninin beyin travması sonrası serebral iskeminin oluşması üzerine olan etkisini araştıran herhangi bir çalışma yoktur. Bu nedenle, sıçanlarda deneysel fokal beyin travması oluşturduk ve zamansal seyri içinde melatoninin travma sonrası serebral iskemi oluşumu üzerindeki etkisini araştırdık. Yöntem: Hayvanlar dört gruba ayrıldı: kontrol (Grup 1), Travmatik Beyin Hasarı (TBH) (Grup 2), TBH artı plasebo (Grup 3) ve TBH artı melatonin (Grup 4). Beyin travması, ağırlık bırakma tekniği ile kontrol grubu dışındaki tüm gruplarda oluşturuldu. Beyin travması oluşturulan grupların her biri belirli zamanlarda (12, 24, 72, 120 ve 168 saatlerde) sakrifiye edilecek şekilde beş alt gruba ayrıldı. İskeminin derecesini göstermede kırmızı nöronların sayısını belirlemek için hematoksilin-eozin (H&E) boyama kullanıldı. Bulgular: Sonuçlarımız, melatonin ile tedavi edilen gruplarda travma ve plasebo gruplarına kıyasla kırmızı nöron sayısının anlamlı bir şekilde azaldığını (P<0.05) gösterdi. Sonuç: Bu çalışma, melatoninin beyin travması sonrasında oluşan iskemiyi azaltığını desteklemektedir. Bu yüzden, melatonin travma sonrası oluşan ikincil serebral yaralanmaları önlemek için potansiyel bir terapötik ajan olarak kullanılabilir. Ancak onun bu etkisinin mekanizmalarını araştırmak için daha ileri çalışmalar gerekmektedir.

Anahtar Kelimeler

• Melatonin
• Travmatik beyin hasarı
• İkincil hasar
• İskemik hasar

Melatonin prevents post-traumatic ischemic damage in rats

Abstract

Aim: Brain trauma is among the leading causes of mortality and long-term disability in the world. Studies suggested that cerebral ischemia is an important mechanism of secondary neuronal injury in traumatic brain injury (TBI), and that melatonin has protective effects on the brain after trauma. It was also shown that melatonin alleviates the formation of cerebral ischemia and ischemic brain damage in many cerebral pathophysiological processes. However, there is no study which investigates the effects of melatonin on cerebral ischemia after brain trauma. Therefore, we aimed to induce experimental focal brain trauma in rats and assess the effects of melatonin on posttraumatic cerebral ischemia. Methods: The animals used in this research were divided into four groups as follows: Control group (Group 1), Traumatic Brain Injury (TBI) group (Group 2), TBI plus Placebo group (Group 3), and TBI plus Melatonin group (Group 4). Brain trauma was induced using the weight drop technique in all groups except the Control group (Group 1). The groups with induced brain trauma were separated into five sub-groups to be sacrificed at the given times (12, 24, 72, 120 and 168 hours). Hematoxylin and eosin (H&E) staining was applied to count the number of red neurons, which indicate the grade of cerebral ischemia. Results: Our results showed that the number of red neurons was significantly less (P<0.05) in the melatonin-treated groups compared to those in the trauma and placebo groups within the same amount of time. Conclusion: The present study found that melatonin markedly inhibits the progression of cerebral ischemia after brain trauma. Therefore, melatonin can be used as a potential therapeutic agent to prevent posttraumatic secondary cerebral injuries. However, further studies are needed to investigate the mechanism of its effect.

Keywords

• Melatonin
• Traumatic Brain Damage
• Secondary Injury
• Ischemic Injury

Kaynakça

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