Table 1

Quantification of labeled metabolites in the media by 1H NMR analysis.

Cell
 [13C Lac] mM
 %13CLac
 [13C Ala] mM
 %13CAla
 [Thr] mM
 [Glc] mM
 Δ[Glc]a mM
 %Glc->Lacb
Rh30 (24 h)
 4.8 ± 0.6
 83 ± 1
 0.35 ± .03
 67 ± 4
 0.15
 6.1 ± 0.6
 4.6 ± .6
 52 ± 7.5
Myocyte(48 h)
 1.2 ± 0.2
 64 ± 2
 <0.01
 <5
 0.15
 4.8 ± .5
 5.9 ± .5
 10 ± 1.4

Concentrations and 13C enrichments of selected metabolites in the medium were determined by NMR integrations as described in the Methods.

a change in medium glucose concentration (= consumption).

b percentage of glucose consumed converted to secreted lactate (cf. text).

Fan et al. Molecular Cancer 2008 7:79   doi:10.1186/1476-4598-7-79