NRF1 and chronic obstructive pulmonary disease: Further detection for the in situ NRF1 and p65 levels by specific antibodies demonstrated that nuclear NRF1 and p65 in pulmonary tissue were increased in COPD group and much higher in GD-COPD group but significantly reduced in GD-T-COPD group (Figure 6H‒K), further confirming that testosterone supplementation inhibited pulmonary inflammation through repressing NRF1 and p65 activation in pulmonary epithelium.