Male apoE−/− mice (20–25 g, 8 weeks) on the C57/BL6 background were provided by Vital River Laboratory Animal Technology Co. Ltd (Beijing, China). Mice were randomized into control, high fat (HF), HHcy, HHcy+scrambled shRNA and HHcy+NLRP3 shRNA groups (n=8 for each group). The control or HF mice were fed a regular diet or HF diet (TD08028, Harlan Teklad, USA) for 10 weeks, respectively. Mice in HHcy, HHcy+scrambled shRNA and HHcy+NLRP3 shRNA groups were fed a HF plus high methionine diet (HF+HM diet, TD08029, Harlan Teklad) for 10 weeks. The HF+HM diet is the HF diet with up to 19.56 g/kg (2%) methionine.3 (link) All mice were kept in certified specific pathogen-free facilities maintained around 24 °C with a 12-h light/dark cycle and free access to food and water. The animal experiments were approved by the Animal Care and Use Committee of Sun Yat-sen University. All animal care and procedures conform to the National Institutes of Health guidelines. At the end of each experiment, mice were anesthetized by an intraperitoneal (i.p.) injection of pentobarbital (80 mg/kg body weight), which was increased (up to 100 mg/kg) if the mice moved or showed pain upon monitoring. The adequacy of anesthesia was evaluated by monitoring toe-pinch reflex and regular respiration. Mice were killed and blood was collected. Plasma was separated and stored at –80°C until further analysis.