Calorie Restriction Protocols for Diabetic Rats

The experimental protocols used in the present study were approved by the Institutional Animal Ethics Committee, and the Deanship of Scientific Research, and College of Pharmacy, Qassim University, Saudi Arabia [Approval ID 2020-CP-12] 10137-cavm-2020-1-3-I. Male Sprague–Dawley rats (aged 3 months) were divided into five groups (six rats per group): a control group (NC), diabetes control group (DC), continuous calorie restriction group (CCR), alternate day calorie restriction group (ALT), and a calorie restriction for 2 days group (PF). The control group received an intramuscular (IM) injection of a vehicle (0.5 % w/v carboxyl methyl cellulose sodium). Hyperglycemia was induced in the other groups by an IM injection of STZ (55 mg/kg). The development of hyperglycemia was confirmed by measuring the rats’ blood glucose levels (Accu-Chek Glucometer, Roche, Germany) after 72 h and on day 4 after the last injection. Rats with fasting blood glucose levels higher than 126 mg/dl were considered to be diabetic and used as subjects in further studies [17 (link)]. The four fasting protocols were started after six weeks (Figure 1).