Dl alanine 15n

Solvents and reagents used in sample preparation and mobile phase were of Optima LC-MS-grade. Methanol (MeOH), water (H₂O), and formic acid were purchased from Fisher Scientific (Illkirch, France). Isotope labeled endogenous metabolite standards (at a minimal purity of 98%), namely 17α-Hydroxyprogesterone-d8 (2,2, 4,6,6,21,21,21-d8), L-Thyroxine-13C6, Succinic acid-2,2,3,3-d4, Pyruvic acid-1-13C, and DL-Alanine-15N were purchased from Sigma Aldrich (St. Quentin Fallavier, France). A working solution at a concentration of 10 μg/mL of each isotope labeled standards was prepared in MeOH.

Methanol (MeOH), water, formic acid (Optima LC/MS grade) and glutamine were purchased from Thermo-Fisher Scientific (Illkirch, France). Isotope metabolite standards including 17α-Hydroxyprogesterone-d₈ (2,2,4,6,6,21,21,21-d8), L-Thyroxine-¹³C₆, Succinic acid-2,2,3,3-d₄, Pyruvic acid-1-¹³C and DL-Alanine-¹⁵N with >98% purity were acquired from Sigma Aldrich (St. Quentin Fallavier, France) as well as oligomycin, carbonyl cyanide 4‐(trifluoromethoxy) phenylhydrazone (FCCP), antimycin A and aspartate. All antibodies (ab42364, EP1332Y, ab186695 and ab186696), the NAD/NADH and ATP Assay Kit (ab65348 and ab83355) were obtained from Abcam (Paris, France) and the Mitotracker® green from Molecular Probes (Oregon, USA). Tris-Glycine Gel was purchased from Life Technologies (Illkirch, France) and DMEM-F12 from Jacques Boy Institute of Biotechnology (Reims, France). The DMEM medium supplemented with FBS (fetal bovine serum) was acquired from PAN-biotech (Wimborne, UK) and the Seahorse XFe Base Medium from Agilent Technologies (Santa Clara, CA, USA).