Loranthus parasiticus extract ameliorates hyperglycemia and improves insulin sensitivity in C57BL/Ksj-db/db mice

Loranthus parasiticus Merr. (L. parasiticus) is a semiparasitic plant and it has antidiabetic effects. But potential application of L. parasiticus to improve insulin sensitivity in mice with type 2 diabetes remains unexplored.Herein, we aimed to investigate the potential antidiabetic effects of L. parasiticus extract (LPE) on hyperglycemia and insulin sensitivity in C57BL/Ksj-db/db mice. C57BL/Ksj-db/db mice were divided into three groups: diabetic control, rosiglitazone, and LPE. Db/db-control group was fed a standard semi-synthetic diet (AIN-93 G), db/db-RG group was fed AIN-93 G supplemented with rosiglitazone (RG) (0.005%, w/w), and db/db-LPE group was fed AIN-93 G supplemented with LPE (0.5%, w/w) for 6 weeks. Mice supplemented with LPE exhibited significantly lower blood glucose and glycosylated hemoglobin levels than diabetic control mice. Compared with diabetic control mice, LPE-supplemented mice exhibited a significant reduction in the homeostatic index of insulin resistance. LPE supplementation stimulated the pIRS Tyr612 and AktSer473, as well as the activation of PI3K in the skeletal muscle insulin signaling pathway. Furthermore, LPE supplementation significantly increased the pAMPKThr172 and ACCSer79 and the expression of plasma membrane GLUT4. LPE supplementation improves insulin sensitivity and alleviates hyperglycemia in diabetic mice.