Fourteen-week-old Dio mice, which had already been given a high fat diet (D12492) for 8 weeks, were purchased from JAX Lab (stock #000664). After quarantine, the mice were divided into three groups. Each group had 8 mice. For 2 weeks, 10 µg/kg body weight/day of HDAC3 inhibitor was administrated by intraperitoneal injection. Control groups were given PBS with 0.1% DMSO (solvent). Pioglitazone was applied in the diet at the dose of 10 mg/kg body weight/day. ITT was conducted by intraperitoneal injection of insulin (I9278, Sigma) at 0.75 unit/kg of body weight in mice after a 4-h fast, as described elsewhere (Gao et al. 2009 (link)). Blood glucose was monitored in the tail vein blood using the FreeStyle blood glucose monitoring system (TheraSense, Phoenix, AZ).