Figure 8. Inflammation and apoptosis in the muscle layer from aged colon. Both aged mice (A) and old people (B) exhibited elevated mRNA expression levels of classic pro-inflammatory cytokines including TNF-α, IL-1β and IL-6 compared with those from young. GAPDH was used as internal control. Reduced expression of Bcl-2 (C) and a rise in expression of cleaved caspase-3 (D) were revealed by western blot analysis. The densitometric analysis of protein expressions normalized to β-actin. Statistical analysis was performed using Student’s t-test and data were represented as mean ± SD, statistical significance is: * P < 0.05, ** P < 0.01, *** P < 0.001 compared with young group; n=5 mice or 4 human samples per group.