Peroxisome proliferator-activated receptor gamma 1 expression in porcine white blood cells: Dynamic regulation with acute endotoxemia

Peroxisome proliferator-activated receptor gamma (PPAR gamma), a primary re gulator of adipocyte differentiation, has been implicated in the regulation of monocyte and macrophage function in vitro. We report that PPAR gamma pr otein is expressed in porcine peripheral white blood cells (WBC), and that PPAR gamma 1 but not gamma 2 mRNA predominates. Additionally, we provide th e first evidence that in vivo lipopolysaccharide challenge (LPS, 25 mu g/kg BW) causes a dynamic increase in PPAR gamma protein expression in peripher al WBC (P < 0.05). PPAR gamma expression was increased 2-fold over basal (1 hr post-LPS), was maximal by 4 hr (3-fold), and was normalized to control by 8 hr post-LPS. Changes in PPAR gamma expression coincided with or closel y followed LPS-induced changes in plasma cortisol, TNF-alpha, insulin, IGF- 1, glucose, and free fatty acids. These data suggest that induction of PPAR gamma expression in WBC may play a role in host response to acute inflamma tory challenge and may prove to be an important target of anti-inflammatory therapies. (C) 1999 Academic Press.