Effects of CSE on GSH based antioxidant system. a Microarray studies revealed an up-regulation in gene expression of two major genes involved in GSH synthesis, SLC7A11 and GCLM; b quantitative assessment using real-time PCR and western blot analyses confirm microarray analysis. c mRNA expression of modifier and catalytic subunits of GLC and protein expression of GCLC and GCLM following CSE exposure derived from 3R4F and ULN products including nicotine. Representative western blots were shown with actin as a loading control; d GSH/GSSG ratio was determined using Thiol green reagent, as mentioned in the methods section. Data were expressed as mean ± SEM (fold change over control). *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001 vs. control. n = 6 biological replicates/condition.