Fig. 4.

LA improves GSH synthetic capacity and hepatic GSH levels. Western analysis of GCL subunits was performed after LA injection at times indicated in A. Results show that GCLC levels in old rats were maximally increased in response to LA within 24 h (A). GCLM also exhibited a similar time-dependent increase, but the difference observed was not statistically significant (A). Paralleling the increase in GCL levels, enzyme activity increased by two-fold within 24 h after LA injection (B). The changes in GCL levels and enzyme activity resulted in an overall increase in hepatic GSH 24 h post LA injection (C). The dashed lines in B and C indicate mean experimental values seen in young animals. Results are expressed as the mean ± SEM. †, Groups that are significantly (P < 0.05) different from old controls.