Aim: To validate the Gubra DIO-rats as a useful animal model of human obesity.
Methods: The Gubra diet-induced obesity (DIO) rat model was based on male Sprague-Dawley rats with ad libitum access to regular chow and a palatable diet rich in fat and sugar. To evaluate the versatility of the Gubra DIO-rats as a valid model of human obesity syndrome, the efficacy of two weight loss compounds, liraglutide and sibutramine, with different mechanisms of action, were examined in 7-month-old Gubra DIO-rats. Liraglutide (200 μg/kg, subcutaneous) was administered twice daily, and sibutramine (5 mg/kg, oral) was administered once daily for 23 days.
Results: Both compounds effectively reduced food intake, body weight, and total fat mass, as measured by nuclear magnetic resonance. The 5-HT reuptake inhibitor/5-HT receptor agonist sibutramine reduced the intake of both regular chow and the Gubra diet. The GLP-1 analogue liraglutide predominantly reduced intake of the highly palatable diet, indicating a shift in food preference. Additionally, sibutramine lowered the insulin sensitivity index, primarily through reductions in glucose-stimulated insulin secretion.
Conclusion: The Gubra DIO-rat model responds well to two weight loss compounds with distinct mechanisms of action. Moreover, this model can be particularly useful for testing compounds with potential effects on diet preference.
