Ppar Gamma Partial Agonist Gq-16 Strongly Represses A Subset Of Genes In 3t3-L1 Adipocytes

Thiazolidinediones (TZDs) are peroxisome proliferator-activated receptor gamma (PPAR gamma) agonists that improve insulin resistance but trigger side effects such as weight gain, edema, congestive heart failure and bone loss. GQ-16 is a PPAR gamma partial agonist that improves glucose tolerance and insulin sensitivity in mouse models of obesity and diabetes without inducing weight gain or edema. It is not clear whether GQ-16 acts as a partial agonist at all PPAR gamma target genes, or whether it displays gene-selective actions. To determine how GQ-16 influences PPAR gamma activity on a gene by gene basis, we compared effects of rosiglitazone (Rosi) and GQ-16 in mature 3T3-L1 adipocytes using microarray and qRT-PCR. Rosi changed expression of 1156 genes in 3T3-L1, but GQ-16 only changed 89 genes. GQ-16 generally showed weak effects upon Rosi induced genes, consistent with partial agonist actions, but a subset of modestly Rosi induced and strongly repressed genes displayed disproportionately strong GQ-16 responses. PPAR gamma partial agonists MLR24 and SR1664 also exhibit disproportionately strong effects on transcriptional repression. We conclude that GQ-16 displays a continuum of weak partial agonist effects but efficiently represses some negatively regulated PPAR gamma responsive genes. Strong repressive effects could contribute to physiologic actions of GQ-16. (C) 2015 Elsevier Inc. All rights reserved.