All BALB/C nude mice were purchased from Huafukang Biotechnology (Beijing, China). These mice were 5 weeks old and weighed 14-16 g. We established subcutaneous tumour-forming mouse model by injecting 5 x 10⁶ U87 cells into the lateral abdomen of BALB/C nude mice. Animals were then treated with DHA solvent (50 mg/kg) by intragastric administration once a day for 26 days.

Mouse renal I/R model was performed in male C57BL/6 mice (8-12 weeks old). Briefly, the mice were anesthetized with pentobarbital sodium by intraperitoneal injection and lay on the right side. Dorsal incisions of both left and right sides were made to expose kidneys. The right kidney artery was gently separated with cotton swabs and occluded with a microvascular clamp to induce renal ischemia for 45 min. The left renal pedicle clamping and ischemia were the same as right. After ischemia, the micro-aneurysm clips were removed to start the reperfusion. The wounds were sutured and resuscitated with warm sterile saline intraperitoneally. All operations were the same in the sham group except for clamping and ischemia.