The Effect of Alternate-Day Fasting on Endothelin-1 Levels in Male Wistar Rats Induced by a High-Calorie Diet

Overweight has become a global health problem, reaching 1 billion cases in 2022. In Indonesia, its prevalence increased from 8.8% in 2013 to 21.8% in 2018, contributing to cardiovascular risk through elevated plasma and renal endothelin-1 (ET-1) levels. This study aimed to evaluate the effect of alternate-day fasting (ADF) on plasma and renal ET-1 levels in male Wistar rats induced by a high-calorie diet, and to assess the anti-endothelin effect of bosentan (125 mg). A post-test-only control group experimental design was used with 18 rats divided into three groups: healthy control, ADF, and anti-endothelin. Obesity was induced for 9 weeks using a high-fat diet, followed by a 4-week intervention. ET-1 levels were measured using ELISA and analyzed using SPSS. The results showed significant weight loss in the ADF group (p = 0.001), but no significant difference in plasma ET-1 levels (p = 0.566). Renal ET-1 levels remained higher compared to the control group (p = 0.001). The anti-endothelin group showed no significant changes in body weight or plasma ET-1, while renal ET-1 levels also remained elevated. In conclusion, ADF reduces body weight but does not normalize renal ET-1 levels. Longer interventions and combined approaches are recommended.