Novel Biphasic Role of Resolvin D1 on Expression of Cyclooxygenase-2 in Lipopolysaccharide-Stimulated Lung Fibroblasts Is Partly through PI3K/AKT and ERK2 Pathways.

Mediators of inflammation

PubMedID: 24174713

Wu D, Zheng S, Li W, Yang L, Liu Y, Zheng X, Yang Y, Yang L, Wang Q, Smith FG, Jin S. Novel Biphasic Role of Resolvin D1 on Expression of Cyclooxygenase-2 in Lipopolysaccharide-Stimulated Lung Fibroblasts Is Partly through PI3K/AKT and ERK2 Pathways. Mediators Inflamm. 2013;2013964012.
Fibroblasts, far frombeing merely bystander cells, are known to play a specific role in inflammation resolution after an acute injury. As the endogenous "braking signal," resolvins possess potent anti-inflammatory and proresolution actions. We demonstrated that the expression of COX-2 protein was significantly peaked initially at 6 hours but then also at 48 hours after LPS stimulation in lung fibroblasts. PGE2 levels also peaked at 6 hours, and PGD2 levels were increased and peaked at 48 hours. However, no significant change in the protein expression of COX-1 was observed after treatment with LPS in lung fibroblasts. Exogenous resolvin D1 inhibited the first peak of COX-2 expression as well as the production of PGE2 induced by LPS. In contrast, exogenous resolvin D1 increased the second peak of COX-2 expression as well as the production of PGD2 induced by LPS. In addition, resolvin D1 inhibited COX-2 expression at 6 hours, which was partly through PI3K/AKT and ERK2 signalling pathways.