Anti-inflammatory properties of pigment epithelium-derived factor

Inflammation is part of the complex biological response to harmful stimuli, such as cell damage, pathogens, or irritants. An excessive inflammatory response can lead to a variety of diseases. Pigment epithelium-derived factor (PEDF) is an endogenous glycoprotein that belongs to the superfamily of serine protease inhibitors and has multiple biological activities. Accumulating evidence suggests that PEDF participates in various inflammatory-related diseases, such as diabetic retinopathy, atherosclerosis, nonalcoholic steatohepatitis, and retinal diseases. However, the mechanism is still incompletely understood. In this paper, we review the anti-inflammatory properties of PEDF and discuss the underlying mechanisms. PEDF can exert its anti-inflammatory effects by downregulating the expression of inflammatory factors, promoting the synthesis of anti-inflammatory factors, inhibiting the activation of proinflammatory pathways and activating anti-inflammatory pathways. Examining the function of PEDF in inflammation addresses the need for further investigation and subsequent target-specific strategies for inflammatory disorders.