Figure 2.

Regulation of respiratory complications by metformin. By preventing the mitochondrial respiratory chain complex 1, metformin increases AMPK levels. Metformin prevents activation of the NF-κB signaling pathway and NLRP3 inflammasome pathway in an AMPK-dependent and -independent manner. Thus, by preventing immune and inflammatory responses, metformin prevents airway inflammation, airway remodeling, and hyperresponsiveness during respiratory complications. AMPK: AMP-activated protein kinase; IL-1b: interleukin -1b; NF-κB: nuclear factor kappa binding protein; NLRP3: NLR family pyrin domain containing 3; and ROS: reactive oxygen species.