Lorcaserin Effects on Diet-Induced Obesity

To induce obesity, male C57BL/6J mice were fed a high-fat diet (HFD, D12492, 60% energy from fat; Research Diets Inc., New Brunswick, NJ, United States) for 12 weeks and then were injected intraperitoneally with lorcaserin (616202-92-7, Aladin, Shanghai, China) at a concentration of 2.5, 4 or 10 mg/kg once a day for 2 weeks based on previous researches (Burke et al., 2017 (link); Patel et al., 2020 (link)). Chronic injection of lorcaserin in diet-induced obesity (DIO) mice received intraperitoneal injections of lorcaserin at 2.5, 4 or 10 mg/kg as described above, whereas acute injection were only received a single intraperitoneal administration of lorcaserin. After fasting [16 h for intraperitoneal glucose tolerance test (IPGTT), 6 h for intraperitoneal insulin tolerance test (IPITT)], mice in acute and chronic treatment groups were all injected intraperitoneally with lorcaserin. 45 min later, 1.2 mg/kg glucose or 1 U/kg insulin were injected intraperitoneally into the mice, and blood was sampled from tail vein immediately prior to lorcaserin treatment, immediately prior to glucose or insulin injection, and 15, 30, 60, 90 and 120 min following glucose or insulin administration. Blood glucose was analyzed using an AlphaTRAK glucometer (Abbott Animal Health) and plasma insulin measurements with ELISA test kits (Ezassay Biotech Co., Ltd., Shenzhen City, China).