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Global lipidomic analysis of hippocampus was performed using ultra-performance liquid chromatography (UPLC) coupled with trapped ion mobility (TIMS) time-of-flight (TOF Weighed hippocampus tissue samples were placed into homogenizer tubes, each containing three 2.8 mm zirconium oxide beads. For solvent extraction, 1.2 mL of 50% methanol/chloroform (1:1, v/v) was added to each tube, based on a tissue weight of 25 mg, ensuring a consistent weight-to-solvent ratio across all samples, after which the tissues were homogenized. After homogenization, the samples were left to stand at 4°C for 10 minutes, followed by centrifugation at 12,700 rpm for 20 minutes. The lower lipid phase was aliquoted into 100 μL, and the solvents were removed using nitrogen gas. The dried extracts were reconstituted in 200 μL of 80% isopropanol, vortexed for 1 minute. They were then centrifuged at 12,700 rpm for 10 minutes at 4 °C, and 100 μL of the supernatants transferred to vials for lipidomic analysis.

Untargeted lipid profiling was performed using high-performance liquid chromatography (HPLC; 1290 Infinity; Agilent) coupled with trapped ion mobility spectrometry time-of-flight (TIMS-TOF; Bruker). The column oven and auto-sampler temperatures were maintained at 55 °C and 4 °C, respectively. The samples were eluted and separated using an Acquity UPLC CSH C18 column (2.1 x 100 mm with 1.7-μm particles; Waters). The LC mobile phase comprised, in positive ion mode, 10 mM ammonium formate and 0.1% formic acid in an acetonitrile/water mixture (6:4, v/v) (solvent A) and 0.1% formic acid in an acetonitrile/isopropanol mixture (1:9, v/v) (solvent B). In negative ion mode, the LC mobile phase comprised 10 mM ammonium acetate in an acetonitrile/water mixture (4:6, v/v) (solvent A) and an acetonitrile/isopropanol mixture (1:9, v/v) (solvent B). Gradient elution began with 40% B, increased to 43% B by 2 minutes, and then gradually increased to 50% B by 2.1 minutes. The composition was further increased to 54% B by 12 minutes, followed by a continuous increase to 99% B by 18 minutes. The composition was held at 99% B for 0.1 minutes, it was returned to initial conditions after 18.1 minutes, and was finally maintained for 2 minutes until equilibration. The flow rates were set to 400 μL/min. For lipid analysis, 2 μL of lipid extract was injected for positive ion mode, and 4 μL was injected for negative ion mode into the HPLC/TIMS-TOF system. All samples were pooled in equal amounts to generated a quality control (QC) sample.

For MS analysis, the mass range was set to m/z 50–1500. The operating parameters were as follows: capillary voltage of 4500 V, end plate offset of 500 V, nebulizer pressure of 2.2 bar for positive ion mode and 2.0 bar for negative ion mode, drying gas flow rate of 10.0 L/min, and source temperature of 220 °C.