CASP3 and chronic obstructive pulmonary disease: LPS/cigarette-induced pulmonary damage, as indicated by apoptosis with TUNEL assay (Figure 5E and G) and caspase-3 expression (Figure 5F and H), was observed in COPD group and worsened in GD-COPD group but significantly alleviated by testosterone supplementation in GD-T-COPD group.