Efek Pemberian ACTH4-7 Pro8-Gly9-Pro10 (MEHFPGP) Intranasal Terhadap Proliferasi Neural Progenitor / Stem Cells (NPSCs) Setelah Cedera Otak Traumatik

Abstract

Introduction: Traumatic Brain Injury (TBI) causes disability, death and huge economic losses in various countries of the world. TBI incident varies between 67 – 317 per 100.000 population, with 4-7% mortality rate in moderate brain injury, and 50% in severe brain injury. Neural progenitor / stem cells (NPSCs) that survive in certain parts of the brain over the life of the animal, give the brain the ability to produce new neurons and glia. Neurogenesis occurs in the subgranular zone (SGZ) of the hippocampus dentate gyrus (DG). ACTH4-10Pro8-Gly9-Pro10 is an ACTH4–10 analog free from hormonal effects and has a neuromodulatory effect, which has a modulation effect on the expression and activation of the BDNF / TrkB system in the hippocampus area. The BDNF / TrkB pathway system is a potential therapeutic target for neurological disorders in traumatic brain injury / TBI. Objective : To investigate the effect of intranasal ACTH4-10Pro8-Gly9-Pro10 (MEHFPGP) as a proliferation promoter of neural progenitor / stem cells (NPSCs) in rat with traumatic brain injury. Design: Laboratory experimental, randomized post test only control group design. Methods: Laboratory experimental study with "Randomized post test only control group design" which used thirty male Sprague-Dawley rats. Rats were divided into three treatment groups, group A (negative control), group B given traumatic brain injury / TBI, group C given traumatic brain injury / TBI + intranasal ACTH4-10Pro8-Gly9-Pro10 (MEHFPGP) administration. After 24 hours, rats’s brain tissue was immunohistochemically processed, to observe the number of cells expressing BDNF, TrkB, and SOX2 in the subgranular zone (SGZ) of the hippocampus dentate gyrus (DG). Data were analyzed with SPSS 17, ANOVA analysis followed by Post Hoc Tukey HSD test, with p value < 0,05. Result : ANOVA analysis, mean expression of BDNF group C = 16.33 ± 2.83 compared to group A (control) = 8.33 ± 1.32 increased significantly (p=0.0001), and mean expression of TrkB group C = 17.00 ± 1.58 increased significantly compared to group A = 4.33 ± 1.73 (p=0.000001) and group B = 5.89 ± 2.47 (p=0.0001), TrkB expression in group B increased insignificantly compared to group A (p= 0.234). Mean expression of SOX2 in group C = 12.56 ± 2.07 increased significantly compared to group B = 8.89 ±2.318 (p=0.0001) and group A= 4.89 ± 2.42 (p=0.0001). Conclusion : ACTH4-10Pro8-Gly9-Pro10 (MEHFPGP) can increase the expression of BDNF and TrkB, and increase the proliferation of NPSCs in the subgranular zone (SGZ) of the hippocampus dentate gyrus (DG).

Pendahuluan : Cedera otak traumatik / Traumatic Brain Injury (TBI) merupakan penyebab kecacatan, kematian dan kerugian ekonomi yang besar di berbagai negara di dunia. Insiden TBI bervariasi antara 67 – 317 per 100.000 penduduk, dan mortalitasnya sekitar 4%-7% pada cedera otak sedang, dan 50% pada cedera otak berat. Sel progenitor/punca neural (neural progenitor/stem cells (NPSCs)) yang bertahan di bagian tertentu dari otak sepanjang umur hewan, memberikan kemampuan otak untuk menghasilkan neuron dan glia baru. Neurogenesis terjadi di subgranular zone (SGZ) dari hippocampus dentate gyrus (DG). ACTH4-10Pro8-Gly9-Pro10 merupakan analog ACTH4–10 bebas dari efek hormonal dan memiliki efek neuromodulatoris, yakni memiliki efek modulasi terhadap ekspresi dan aktivasi sistem BDNF/TrkB pada daerah hippokampus. Sistem BDNF/TrkB pathway merupakan target terapi yang potensial untuk gangguan neurologi pada cedera otak traumatik/TBI. Tujuan : Untuk mengetahui efek ACTH4-10Pro8-Gly9-Pro10 (MEHFPGP) intranasal sebagai promoter proliferasi sel progenitor/punca neural (neural progenitor/stem cells (NPSCs)) pada tikus yang mengalami cedera otak traumatik. Desain Penelitian : Eksperimental laboratorik, randomized post test only control group design. Metode : Penelitian eksperimental laboratorik dengan desain “Randomized Post test only control group design” yang menggunakan tiga puluh tikus Sprague–Dawley jantan. Tikus di bagi dalam tiga kelompok perlakuan, yakni kelompok A (kontrol negatif), kelompok B yang diberikan cedera otak traumatik/TBI, kelompok C yang diberikan cedera otak traumatik/TBI + pemberian ACTH4-10Pro8-Gly9-Pro10 (MEHFPGP) intranasal. Setelah 24 jam, jaringan otak tikus diproses immunohistokimia, untuk diamati jumlah sel yang mengekspresikan BDNF, TrkB, dan SOX2 pada subgranular zone (SGZ) dari hippocampus dentate gyrus (DG). Data dianalisa dengan SPSS 17, analisa ANOVA dilanjutkan uji Post Hoc Tukey HSD, dengan nilai p < 0,05. Hasil : Analisa ANOVA, rata-rata ekspresi BDNF kelompok C = 16.33 ± 2.83 dibandingkan kelompok A (kontrol) = 8.33 ± 1.32 meningkat signifikan (p=0.0001), dan rata-rata ekspresi TrkB kelompok C = 17.00 ± 1.58 meningkat signifikan dibanding kelompok A = 4.33 ± 1.73 (p=0.000001) dan kelompok B = 5.89 ± 2.47 (p=0.0001), ekspresi TrkB pada kelompok B meningkat tidak signifikan dibandingkan kelompok A (p= 0.234). Rata-rata ekspresi SOX2 kelompok C = 12.56 ± 2.07 meningkat signifikan dibanding kelompok B = 8.89 ± 2.318 (p=0.0001) dan kelompok A= 4.89 ± 2.42 (p=0.0001). Kesimpulan : ACTH4-10Pro8-Gly9-Pro10 (MEHFPGP) dapat meningkatkan ekspresi BDNF dan TrkB, serta meningkatkan proliferasi NPSCs pada subgranular zone (SGZ) dari hippocampus dentate gyrus (DG).