Skripsi

Impact of Intermittent and Prolonged Fasting towards Renal Oxidative Stress in the New Zealand White Rabbit = Pengaruh Puasa Intermiten dan Diperpanjang terhadap Kadar Marka Stres Oksidatif di Ginjal Kelinci Putih Selandia Baru.

Introduction: Calorie restriction (CR) shows promise as a method in mitigating kidney damage due to oxidative stress as it has shown to reduce renal damage by reduction of inflammation, stimulation of autophagy, and improvement of antioxidant activity. Current understanding of the protective role of fasting as a form of CR remains limited to studies in rodents and lower species. As a result, this study investigates the impact of intermittent (IF) and prolonged fasting (PF) to oxidative stress markers in kidney samples of the New Zealand white rabbit. Methods: 15 rabbits were separated into 3 groups: control, IF, and PF groups. Rabbits were fasted in cycles of 16h for IF and 40h for PF, both interspersed by 8h ad libitum feeding. Fasting regiment was done for a period of 7 days. Colorimetric analysis to measure concentrations of malondialdehyde (MDA) using the TBARS assay and carbonyl using the DNPH assay was then conducted on homogenized renal samples. ANOVA parametric analysis was then conducted to compare results between groups. Results: Analysis revealed a statistically insignificant difference of both MDA and carbonyl concentrations between control, IF, and PF groups (p > 0.05). However, mean concentrations of MDA shows a trend of increased mean concentration in PF (26.29 nmol/mL) followed by IF groups (23.47nmol/mL) compared to the control (18.99 nmol/mL). Mean carbonyl concentrations also depict a trend of higher concentration in the PF group (9.33nmol/mL), but IF (7.24nmol/mL) had lower mean concentration than the control (7.91nmol/mL). Conclusion: The IF and PF regiment conducted for 7 days do not show to have any statistically significant effect on oxidative stress marker levels in the rabbit kidney. Further research modifying period or duration of fasting is suggested to evaluate potential application of fasting in mitigating kidney disease.
Key words: Oxidative stress, intermittent fasting, prolonged fasting, malondialdehyde, protein carbonyl


Pendahuluan: Pembatasan kalori menunjukan potensi sebagai metode untuk meringankan kerusakan jaringan ginjal akibat stres oksidatif karena kemampuannya untuk mengurangi peradangan, menstimulasi autofagi, dan meningkatkan aktivitas antioksidan. Pemahaman terkini mengenai potensi protektif dari puasa sebagai bentuk pembatasan kalori masih terbatas pada penelitian di hewan rodensia dan spesies rendah lainnya. Oleh karena itu, studi ini dilakukan untuk menilai dampak puasa intermiten (IF) dan diperpanjang (PF) terhadap marka stres oksidatif di sampel ginjal kelinci putih Selandia Baru. Metode: 15 kelinci dikelompokkan menjadi kelompok kontrol, IF, dan PF. Kelinci dipuasakan selama 16 jam untuk kelompok IF dan 40 jam untuk kelompok PF, masingmasing diselingi dengan pemberian makanan secara ad libitum selama 8 jam. Siklus puasa-makan diulang selama 7 hari. Analisis kolorimetri dilakukan untuk menilai konsentrasi malondialdehid (MDA) dengan metode thiobarbituric acid reactive substance (TBARS) assay dan karbonil menggunakan 2,4-dinitrophenylhydrazine (DNPH) assay di sampel ginjal terhomogenisasi. Analisis parametrik dengan ANOVA kemudian dilakukan untuk membandingkan hasil antara kelompok. Hasil: Analisis menunjukan tidak berbeda signifikan secara statistik antara kelompok kontrol, IF, dan PF pada konsentrasi MDA dan karbonil (p > 0.05). Namun, nilai rata-rata MDA menunjukan kecenderungan peningkatan konsentrasi tertinggi di kelompok PF (26.29 nmol/mL), diikuti dengan kelompok IF (23.47nmol/mL), dan kontrol (18.99 nmol/mL). Rata-rata nilai karbonil juga menunjukan nilai tertinggi di kelompok PF (9.33nmol/mL), namun rata-rata konsentrasi IF (7.24nmol/mL) lebih rendah dibanding kontrol (7.91nmol/mL). Kesimpulan: Pemberian puasa IF dan PF selama 7 hari tidak menunjukan dampak signifikan secara statistik terhadap marka stres oksidatif di ginjal kelinci. Riset lebih lanjut dengan modifikasi lama dan jangka puasa disarankan untuk menilai potensi aplikasi puasa dalam meringankan penyakit ginjal.
Kata kunci: Stres oksidatif, puasa intermiten, puasa jangka panjang, malondialdehid, karbonil protein