Evaluation of anti-obesity activity of adipotide in obese rats
1. Materials and methods:
1.1.1 Rats: Ten healthy male SD rats (175-185 Grams) were purchased in accordance with the policy and regulations for care and use of laboratory animals from Harlan Laboratories
1.1.2 Peptides: 48 vials of Adipotide(5 mg/vial), from Labpe Peptides.
1.2.1 Grouping of animals and induction of obesity: Ten healthy male SD rats (175-185 Grams) were initially divided into 5 groups: group A (n = 2) and group B (n = 8). The rats were housed individually in standard mouse cages with a 12-h light/12-h dark cycle. Group A was fed with a low-fat diet (LFD) with 5.28% calories as fat (M01-F) and group B was fed with a high-fat diet (HFD) providing 16.20% calories as fat (M04-F) for 5 weeks, respectively, followed by a 1 week wash out period under LFD. Groups A and B were further divided as described in Table 1. After 6 weeks, all animals were fed LFD for 4 weeks along with their respective drug treatment.
Table 1. Grouping of aninmals. Group A: animals fed on LFD Group A: Normal animals treated with the same dose of 0.5% DMSO/saline(s.c., 4 weeks; n=2) Group B: animals fed on HFD Group 1B: Obese animals treated with the same dose of 0.5% DMSO/saline(s.c., 4 weeks; n=2) Group 2B: Obese animals treated with 2 mg/kg adipotide in 0.5% DMSO/saline(s.c., 4 weeks; n=2) Group 3B: Obese animals treated with 4 mg/kg adipotide in 0.5% DMSO/saline(s.c., 4 weeks; n=2) Group 4B: Obese animals treated with 8 mg/kg adipotide in 0.5% DMSO/saline(s.c., 4 weeks; n=2)
1.2.2 Treatment: Adipotide was dissolved in 0.5% DMSO/saline and administered in the subcutaneous tissue of the back of rats in group 2B, group 3B and group 4B at a daily dose of 2mg/kg, 4mg/kg and 8mg/kg for 4 weeks, respectively. The drug was administered daily 2 h before food administration for a period of 4 weeks. Group A and group 1B animals were administered the same dose of 0.5% DMSO/saline solution.
1.2.3 Parameters assessed of Anti-obesity activity:
Body mass was measured daily at 21:45 h before administrating food.
Food intake was measured daily at 6:00 h, 10 h after drug administration.
Rectal temperature was measured after 6 h of dosing using a rectal thermometer every week.
At the end of study, animals are anatomized, and epididymal fat pads were removed to measure relative adiposity (percentage epididymal fat pad mass of total body mass in grams).