Fig. 2: G6PDH controls cell survival and NADPH-mediated glutathione recycling.
a,b, H&E staining of P3 growth plates of WT (G6pdhchon+) and chondrocyte-specific G6PDH-deficient (G6pdhchon−) mice (a), with quantification of the growth plate area (b) (n = 15; unpaired two-sided Student’s t-test vs G6pdhchon+). Boxed areas are magnified in a (right panels). Scale bar, 100 µm. c, Cell density in the resting and columnar zones of P3 G6pdhchon+ and G6pdhchon− growth plates, quantified on Hoechst staining (n = 8; unpaired two-sided Student’s t-test vs G6pdhchon+). d,e, BrdU immunostaining of P3 G6pdhchon+ and G6pdhchon− growth plates (d), with quantification of BrdU+ cells in the resting and columnar zones (e) (n = 8; unpaired two-sided Student’s t-test vs G6pdhchon+). Scale bar, 100 µm. f, Schematic of the effect of G6PDH deletion on oxPPP and non-oxPPP activity. Glc, glucose; glc-6-P, glucose-6-phosphate; TKT, transketolase. g, UMP m+1 (oxPPP) and m+2 (non-oxPPP) labelling from [1,2]-13C2 glucose in G6pdhchon+ and G6pdhchon− chondrocytes (n = 4; unpaired two-sided Student’s t-test vs G6pdhchon+). h, TUNEL staining on P3 G6pdhchon+ and G6pdhchon− growth plates (n = 8). Scale bar, 100 µm. i, Dead cells, measured by SYTOX Green flow cytometry, in differentiated hypoxic chondrocytes from G6pdhchon+ and G6pdhchon− mice (n = 3; unpaired two-sided Student’s t-test vs G6pdhchon+). j, NADPH and NADP+ levels in differentiated hypoxic chondrocytes from G6pdhchon+ and G6pdhchon− mice (n = 3; unpaired two-sided Student’s t-test vs G6pdhchon+). AU, arbitrary units. k, NADPH:NADP+ ratio in differentiated hypoxic chondrocytes from G6pdhchon+ and G6pdhchon− mice (n = 3; unpaired two-sided Student’s t-test vs G6pdhchon+). l, GSH:GSSG ratio in differentiated hypoxic chondrocytes from G6pdhchon+ and G6pdhchon− mice (n = 3; unpaired two-sided Student’s t-test vs G6pdhchon+). m, H2O2 levels, quantified by CellMeter Hydrogen Peroxide flow cytometry, in differentiated hypoxic chondrocytes from G6pdhchon+ and G6pdhchon− mice (n = 3; unpaired two-sided Student’s t-test vs G6pdhchon+). MFI, mean fluorescence intensity. n, Schematic of the effect of G6PDH deletion on growth plate chondrocytes. The data are presented as means ± s.d.
