NOS2 and acute lung injury: Magnolol has been investigated for protecting acute lung injury (ALI) and proved to greatly upregulate the expression of PPARγ and suppress the expression of NF-κB signaling, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) and the production of ROS in bronchoalveolar lavage fluid, resulting in improvement of lung edema and polymorphonuclear neutrophil infiltration [34] (Table 1).