Objective: To study the protective effects and mechanism of loureirin B on the dysfunctiion of pancreatic islet β cell induced by palmitic acid. Method: NIT-1 cells were cultured in medium added palmitic acid

and treated with loureirin B. Cell apoptosis ratio and content of reactive oxygen species (ROS) were detected by flow cytometry

the expressions of glucose tnansport receptor-2(GLUT2) was examined by semi-quantitate reverse transcript PCR. Result: Compared with palmitic acid treated group

survival rate of NIT-1 with loureirin B (20

10 μmol· L-1) was increased significantly(P<0.05). Loureirin B (20

10

5 μmol· L-1) scavenged excessive ROS and lowered its concentration significantly (P<0.05). Loureirin B (20 μmol· L-1) was increased the expressions of GLUT2 (P<0.05)

and loureirin B (20

10

5 μmol· L-1) was effective on reducing apoptosis ratio induced by palmitic acid (P<0.05). Conclusion: Loureirin B can increase the survival rate of NIT-1 cultured in the medium added palmitic acid

scavenge excessive ROS induced by palmitic acid

decrease the cell apoptosis ratio and elevate the expressions of GLUT2.This indicates loureirin B may accomplish its islet cell protection effects by reducing ROS within cell and reversing glucose metabolism disorder rand other effects induced by forkhead box protein-1 (FOXO1) activated by oxidative stress.