Cyclopentenone Prostaglandins Inhibit Cytokine-Induced NF-κB Activation and Chemokine Production by Human Mesangial Cells

In the kidney an uncontrolled inflammatory response to an acute insult may lead to chronic inflammation, permanent tissue damage, and progressive renal insufficiency. Resolution of acute inflammation likely is dependent on endogenous regulatory mechanisms activated in parallel with mediators of renal inflammation. These mechanisms are postulated to attenuate the renal expression of proinflammatory cytokines, including the chemokines responsible for recruiting leukocytes to the kidney, thus facilitating the transition from inflammation to healing. To understand the regulation of the inflammatory response within the kidney, the effects of anti-inflammatory J series cyclopentenone prostaglandins on chemokine production by human mesangial cells were examined. Treatment of mesangial cells with prostaglandin J2and 15-deoxy-Δ12,14-prostaglandin J2blocked interleukin-1β—induced monocyte chemoattractant protein-1 mRNA expression and protein production. This correlated with failure of the transcription factor nuclear factor-κB (NF-κB) to translocate to the nucleus and bind to its recognition motif, a step required for cytokine-induced monocyte chemoattractant protein-1 gene activation. NF-κB failed to translocate because the cyclopentenone prostaglandins attenuated degradation of the NF-κB inhibitor IκB-α. These data suggest that certain prostaglandins can limit the extent of renal chemokine expression and thus may have an important role in resolving renal inflammation.