Obesity involves hypoxic adipose tissue and low-grade chronic inflammation. We investigated the impact of hypoxia on inflammatory response to TNF-alpha in white and brown adipocytes. In response to TNF-alpha, the expression of the inducible enzymes iNOS and COX-2 was prominently and selectively potentiated during hypoxia while only moderately under normoxia. Levels of their products, nitrite and prostaglandinE(2) were elevated accordingly. NS398, a selective COX-2 inhibitor, reduced nitrite levels. The expression of PGC-1 alpha, a transcriptional co-activator involved in mitochondrial biogenesis, and PPAR-gamma, a transcription factor involved in adipocyte homeostasis, was reduced by TNF-alpha during hypoxia. These results suggest that hypoxia potentiates the inflammatory response by TNF-alpha in both white and brown adipocytes and downregulates the transcription factors involved in adipocyte function. (C) 2015 Elsevier Inc. All rights reserved.