NMR data of the study: Glucagon is a major controller of metabolism and malignancy in pancreatic neuroendocrine tumour (pNET) cells Submitted to Molecular Medicine Reports

Methods

For nuclear magnetic resonance (NMR) spectroscopy, 1×105 cells/well/500 µL were cultured in 24-well plates, and the supernatant was collected, cleared upon centrifugation (150 × g, 5 min) and stored at -80C until NMR analysis. After starvation, cells were cultured in the experimental conditions for 48 h in the presence of 250 pg/mL of glucagon, without or with glucose (4.5 g/L). NMR spectroscopy was performed to define the exometabolome (metabolic profiles of conditioned culture media) under the influence of glucagon in the absence or presence of glucose in pNET cell lines and in the non-malignant α-TC1 cell line. The supernatants were collected, and centrifuged 150 × g for 3 min, and stored at -80°C to preserve their integrity. For sample preparation, 60 µL of a solution containing 0.022 mM trimethylsilyl propionate-d4 (TSP) and 0.04% (v/v) sodium azide, both in D2O, was added in a 1:1 proportion to each supernatant. TSP serves as an internal standard, providing a reference point for concentration measurements. Subsequently, 1H-NMR spectra were acquired using an Ultrashield Avance 500 Plus spectrometer (Bruker) equipped with a TCI-Z probe, maintaining a controlled temperature of 25°C through measurements. To process and analyse the obtained spectra, the TopSpin 4.1 software (Bruker) was used. Spectral processing techniques, such as baseline correction and referencing, were applied to enhance the quality of the spectra. Additionally, spectral assignments were performed to identify and characterise the metabolites present in the samples by resorting to spectral databases: Chenomx NMR Suite 8.11and Human Metabolome (HMDB).