Figure 2.

Trichostatin A (TSA)–attenuated lipopolysaccharide (LPS) induced nicotinamide phosphoribosyltransferase (NAMPT) expression in human lung endothelial cells (ECs). A, Human lung ECs were pretreated with either vehicle (Veh) or histone deacetylase (HDAC) class I and II–specific inhibitor TSA (400 nM and 1,000 nM) for 20 hours and were further unstimulated or stimulated with LPS (100 ng/mL) for 4 hours. TSA showed marginal statistically insignificant decreases for NAMPT transcripts at both doses in unstimulated cells as assayed by quantitative polymerase chain reaction with primers specific for NAMPT and normalized to glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Pretreatment with TSA-attenuated LPS induced increases in NAMPT messenger RNA. All samples are represented as fold-change of gene expression over Veh; n = 3 independent experiments. Two asterisks indicate P < 0.01 for LPS + TSA − 1,000 nM versus LPS, and one asterisk indicates P < 0.01 for LPS versus Veh. B, TSA pretreatment (1,000 nM) for 1 hour followed by LPS (100 ng/mL) for 24 hours inhibited the induced NAMPT protein analyzed by Western blot (∼2-fold inhibition). Pretreatment with TSA at 1,000 nM, but not 400 nM, significantly attenuated LPS-induced NAMPT protein expression. C, 18% cyclic stretch (CS) significantly increased NAMPT protein expression over 5% CS. These induced increases were significantly decreased with pretreatment of endothelial cells with TSA (1,000 nM).