A study also reported that dandelion total flavonoid extracts could upregulate the mRNA levels of antioxidant genes (Nrf2 and SOD1), regulate the expression levels of proteins related to the Nrf2 signaling pathway, and play a protective role in COPD induced by cigarette smoke by regulating the Nrf2 antioxidant signaling pathway [96]. The gene discussed is SOD1; the disease is chronic obstructive pulmonary disease.