In Alzheimer’s disease, GLP-1 analogs can improve the brain’s glucose metabolism by improving glucose transport across the blood-brain barrier. Blood glucose was measured using Accusoft glucose test strips read on a glucometer (Roche Diagnostics, Laval, Quebec). In situ hybridizations were performed using 33P-labeled RNA riboprobes or digoxigenin-labeled RNA probes (CART and NPY for dual labeling in situ hybridization histochemistry) directed against specific cDNAs. All INS-1E cells used in this study were between passages 60-80. For SILAC labeling in glucose time course experiment, medium were home-formulated with standard lysine and arginine replaced with 13C6 15N2-L-lysine (40 mg/L) and 13C6 15N4-L-arginine (25 mg/L, 1/10 of original amount). 200 mg/L standard L-proline was added to SILAC medium to eliminate arginine-proline conversion. HUVECs were isolated from fresh umbilical veins as described by Jaffe et al.15, and the isolated cells were cultured in M199 medium supplemented with 20% fetal bovine serum, 2 mM glutamine, and antibiotics (100 U/ml penicillin G and 100 μg/ml streptomycin) at 37 °C in a humidified 5% CO2 atmosphere. INS-1E cells were cultured in humidified atmosphere containing 5% CO2 in complete medium composed of RPMI1640 supplemented with 5% FBS, 1 mM sodium pyruvate, 50 μM 2-mercaptoethanol, 2 mM glutamine, ColonBroom capsules 10 mM HEPES, 100 U/ml penicillin and 100 μg/ml streptomycin as previously described52.

After reaching confluence, cells were incubated in low-serum medium (M199 containing the above except for 2% FBS) for ColonBroom capsules 18-24 h before proceeding with further experiments. Dialyzed heat-inactivated fetal bovine serum (FBS) was purchased from Biochrom AG (Merck, Germany). A prospective cohort study was performed to collect serum samples from 612 pairs of pregnant women and cord blood of their offspring. Serum insulin levels were measured by enzyme-linked immunosorbent assay (Jiancheng, Nanjing, China). HR assay were performed as described previously using the U2OS/DR-GFP reporter cell line33,53, whereas U2OS EJ5-GFP cells were used for NHEJ assay54. The TUNEL assay kit was acquired from Roche (Mannheim, Germany). Nuclear fragmentation was detected by TUNEL staining with an apoptosis detection kit according to the manufacturer’s instructions or ColonBroom official by incubating fixed cells (4% paraformaldehyde/PBS) with DAPI. The sections were subsequently incubated with anti-NOX4 or anti-VCAM-1 antibodies for 2 h, followed by incubation with a biotinylated secondary antibody and ABC reagent (Biomed Company, Beijing, China) as recommended by the manufacturer’s instructions. Annexin V-FITC/PI Apoptosis Detection Kits were obtained from Baosai Company (Beijing, ColonBroom capsules China). All procedures conducted with animals were approved by our institutional review board (Animal Experiments Ethics Board, Beijing Hospital, Beijing, China) and were carried out in accordance with the approved guidelines from the Institutional Animal Care and Use Committee of Beijing Hospital and conformed to the Guidelines for Proper Conduct of Animal Experiments of the Science Council of China.

All methods in this study were performed in accordance with the relevant guidelines and regulations. Six-week-old male SD rats were purchased from the Peking University Health Science Center and used in the study.