Fig. 2

Effect of OSM on central carbon metabolism of PH5CH8 under normoxia and hypoxia. a–f PH5CH8 cells were treated with 50 ng/ml OSM, hypoxia (1 % O₂), or a combinatorial treatment, and metabolites were extracted after 36 h. a Relative glutamine and glucose carbon contribution to citrate. b Carbon atom transitions of pyruvate carboxylase (PC) and pyruvate dehydrogenase complex (PDC). c PDC activity determined by the ratio of M2 isotopologues of citrate to M3 isotopologues of lactate, from [¹³C₆]glucose. d Atom transitions for reductive carboxylation and oxidative decarboxylation of α-ketoglutarate. e Oxidative glutamine contribution to citrate, determined by the ratio of M4 isotopologues of citrate to M5 isotopologues of glutamate, from [¹³C₅]glutamine. f Reductive glutamine contribution to citrate, determined by the ratio of M5 isotopologues of citrate to M5 isotopologues of glutamate, from [¹³C₅]glutamine. g–j PH5CH8 cells were treated with different concentrations of OSM. Metabolites and proteins were extracted after 36 h. g HIF-1 α protein levels in PH5CH8 cells after treatment with the indicated OSM concentrations. h PDC activity determined by the ratio of M2 isotopologues of citrate to M3 isotopologues of lactate, from [¹³C₆]glucose. i Oxidative glutamine contribution to citrate, determined by the ratio of M4 isotopologues of citrate to M5 isotopologues of glutamate, from [¹³C₅]glutamine. j Reductive glutamine contribution to citrate, determined by the ratio of M5 isotopologues of citrate to M5 isotopologues of glutamate, from [¹³C₅]glutamine. All error bars indicate the standard deviation. All p values and error bars are calculated from at least two independent replicates (n>=2). Statistical significance was determined in comparison to the untreated control. * P<=0.05, ** P<=0.01, and *** P<=0.001