Peroxisome Proliferator-Activated Receptors (PPARs) are a group of nuclear receptor proteins that play a crucial role in regulating gene expression related to metabolism, inflammation, and cell differentiation. They are activated by specific fatty acids and other ligands, influencing how the body processes fats and sugars. There are three main types of PPARs: PPAR-alpha, PPAR-beta/delta, and PPAR-gamma. Each type has distinct functions and is found in different tissues. For example, PPAR-gamma is primarily involved in fat cell development and insulin sensitivity, making it a target for diabetes treatments.