Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors, which are responsible for regulating gene expression. PPARs are firstly found in the Xenopus frog as nuclear receptors, which induce the proliferation of peroxisomes in the cells. The PPAR family genes comprised of three isoforms PPAR-α, PPAR-β/δ and PPAR-γ, which are expressed in the different tissues in various species including the human.  PPARs induce gene expression through specific interaction with transcription factors, which bind with the promoters of metabolic genes. All PPARs homodimerize with the retinoid X-receptor-α and bind to the specific promoter regions on DNA of the target gene.
The functions of PPARs get altered by the shape of the ligand binding, as well as by the presence of other co-activators or co-repressor proteins, whose presence may alter the expressions of genes. PPARs with other nuclear receptors regulate the transcriptional activities of several transcription factors including nuclear factor-kappa B (NF-κB), which are involved in inflammatory responses. This involves regulation of transcription factors such as the signal transducers and transcriptional activators like STAT, ATF-4, ATF-1, and alteration of expressions of inflammatory molecules like cyclooxygenase-2 (COX-2) and nitric oxide synthase. PPARs regulate inflammatory pathway by several mechanisms. They compete with NF-κB in binding with the overlapping sets of co-activators, like cAMP response element-binding protein (CREB), by inhibiting NF-κB. PP


1.Agarwal S, et al.Biochem Biophys Res Commun. 2017;483(4):1166–1177.