Skripsi

The Impact of Prolonged and Intermittent Fasting on The Expression of Oct4 as a Pluripotency Biomarker in New Zealand White Rabbits Liver = Pengaruh puasa intermiten dan prolonged terhadap ekspresi Oct4 sebagai biomarker pluripotency di sel liver New Zealand White Rabbit.

Introduction: A characteristic of aging is stem cell exhaustion, a condition caused by excessive proliferation and differentiation of stem cells. Consequently, the risk of noncommunicable diseases, e.g. cancer, diabetes, and neurodegenerative diseases, increases with age. A regenerative therapy for these pathologies is dietary restriction (DR), specifically fasting, as studies have demonstrated benefits on local stemness. However, the relationship of DR towards pluripotency remains unclear. Recent studies show that octamer-binding transcription factor 4 (Oct4), a vital pluripotent transcription factor, with hepatocyte nuclear factor 4 alpha (Hnf4a) has a role in the self-renewal of stem cell and differentiation to hepatocytes. Therefore, this research aims to investigate the regenerative ability of fasting by comparing the expression of Oct4 in liver cells of fasted rabbits with rabbits fed ad libitum. Methods: The rabbits were conditioned into 3 different groups. The first was subjected to ad libitum diet, second to intermittent fasting (16- hours fasting), and third to prolonged fasting (40-hours fasting). Afterward, the RNA was extracted from the liver tissues of each rabbit and analyzed via real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). The relative expression was calculated using the Livak method. Results: In comparison to the ad libitum diet, there was a statistically insignificant increase in the relative expression of Oct4 in the liver of intermittent fasted rabbits, and a statistically significant decrease in prolonged fasted rabbits. Conclusion: Prolonged fasting possibly leads to starvation-induced liver injury and decreased stemness, as seen from the decreased expression of Oct4. Future studies should highlight the effect of different expression of Oct4 proteins towards liver cell regeneration.
Key words: octamer-binding transcription factor 4, gene expression, stemness, fasting


Pendahuluan: Sebuah karakteristik penuaan adalah penurunan kepuncaan, sebuah kondisi yang disebabkan oleh proliferasi dan diferensiasi sel punca yang berlebihan. Alhasil, risiko penyakit tidak menular seperti kanker, diabetes, dan penyakit neurodegenerative, meningkat dengan usia. Salah satu terapi regeneratif untuk penyakit tersebut adalah pembatasan diet, khususnya puasa, karena penelitian telah menunjukkan manfaatnya terhadap kepuncaan lokal. Namun, hubungan pembatasan diet dengan pluripotensi masih belum jelas. Studi terbaru menunjukkan bahwa octamer-binding transcription factor 4 (Oct4), faktor transkripsi pluripotensi, bersama dengan hepatocyte nuclear factor 4 alpha (Hnf4a) memiliki peran dalam regenerasi sel punca dan diferensiasi menjadi sel hati. Oleh karena itu, penelitian ini bertujuan untuk menyelidiki kapasitas regeneratif puasa dengan cara membandingkan ekspresi Oct4 dalam sel hati kelinci puasa dengan kelinci diet ad libitum. Metode: Kelinci dirawat dengan 3 diet yang berbeda. Kelompok pertama menjalani diet ad libitum, kedua menjalani puasa intermiten (16 jam), dan ketiga menjalani puasa berkepanjangan (40 jam). Kemudian, RNA diekstraksi dari jaringan hati dari masingmasing kelinci, dan dianalisis melalui qRT-PCR. Metode Livak digunakan untuk mengukur ekspresi relatif gen Oct4. Hasil: Dibandingkan dengan kelinci dengan diet ad libitum, terdapat peningkatan secara tidak signifikan di ekspresi relatif gen Oct4 di hati kelinci yang melalui puasa intermiten dan penurunan secara signifikan di kelinci yang melalui puasa berkepanjangan. Kesimpulan: Berdasarkan penurunan yang signifikan, puasa berkepanjangan mungkin menyebabkan kerusakan jaringan hati dan menurunkan kepuncaan. Penelitian lebih lanjut harus menjelaskan pengaruh ekspresi protein Oct4 terhadap regenerasi sel hati.
Kata kunci: octamer-binding transcription factor 4, ekspresi gen, kepuncaan, puasa