Table 3.

Effects of G6PDi-1 and ES936 on the β-lapachone-induced oxidative stress in astrocytes

	LDH	GSSG content (nmol GSx/ mg protein)		GSx content (nmol/mg protein)		Glucose consumption (µmol/mg protein)	Lactate release (µmol/mg protein)	Lactate release / Glucose consumption
Condition	(%)	Cellular	Extracellular	Cellular	Extracellular	Extracellular	Extracellular	Extracellular
	(120 min)	(10 min)	(120 min)	(120 min)	(120 min)	(120 min)	(120 min)	(120 min)
No inhibitor	9 ± 7	7 ± 5	8 ± 10	31 ± 5	15 ± 11	1.75 ± 0.32	2.78 ± 0.80	1.6 ± 0.3
100 µM G6PDi-1	7 ± 4	24 ± 6**	27 ± 8**	9 ± 1**	37 ± 6**	1.55 ± 0.09	2.07 ± 0.09	1.3 ± 0.1
30 µM ES936	12 ± 7	1 ± 1	2 ± 2	36 ± 10	10 ± 6	1.61 ± 0.23	2.86 ± 0.99	1.7 ± 0.4
G6PDi-1 + ES936	5 ± 5	1 ± 1	3 ± 2	37 ± 9	14 ± 1	1.88 ± 0.15	2.50 ± 0.33	1.3 ± 0.3

The cells were incubated without (No inhibitor) or with G6PDi-1 (100 µM) and/or the NOQ1 inhibitor ES936 (30 µM) in the presence of 5 µM β-lapachone in glucose-containing (5 mM) incubation buffer for up to 2 h. Cellular and extracellular GSx and GSSG contents, extracellular LDH activity (given as percent of the initial cellular LDH activity) as well as glucose consumption, lactate release and the ratio of lactate release to glucose consumption were measured for the indicated time points. The initial specific GSx content of the cultures was 45.5 ± 9.0 nmol/mg protein and the specific GSSG content was 0.1 ± 0.1 nmol GSx/mg protein. The initial protein content of the cultures was 167 ± 34 µg per well. The data presented are means ± SD of values from experiments that had been performed on three independently prepared astrocyte cultures. The significance of differences (as calculated by ANOVA) compared with data for incubations without inhibitor (No inhibitor) is indicated by **p < 0.01