PTAFR and chronic obstructive pulmonary disease: We hypothesize that safflower yellow can partially reverse the pathophysiological process of COPD due to the obvious upregulation of platelet-activating factor receptor in the lung tissue of COPD patients, and safflower yellow's pharmacological effects include inhibiting inflammatory responses and oxidative stress, relieving pulmonary hypertension, reducing hypoxic pulmonary artery remodelling, and reversing right ventricular hypertrophy and remodelling [16, 17].