The possible mechanism of insulin reducing amyloid beta peptide in the brain cortex of diabetic rats / 中华神经科杂志

ABSTRACT

Objective To investigate the reduction of amyloid beta peptide (A?) production induced by insulin in the cortex of diabetic rat. Methods 15 male SD rats were randomly divided into control group, diabetes group, and diabetes plus insulin group. The diabetic rats were induced by streptozotocin. The activity of glycogen synthase kinase-3 (GSK-3) was measured by 32P liquid scintillography for incorporated radioactivity in control group, DM group, DM+insulin group, the production of A? was determined by sandwich ELISA in each group, and the expression of APP was determined by Western-blot. Results In control group, the activity of GSK-3 (1.04?0.11), the production of A? (A?_ 40 (40.92?5.34) pg/?l, A?_ 42 (29.64?3.19) pg/?l)and the levels of full-length APP(1.05?0.08) was low, but in DM group, the activity of GSK-3 (2.02?0.12) and the production of A?(A?_ 40 (67.53?11.69) pg/?l, A?_ 42 (45.02?4.10) pg/?l) increased (P