Downregulating p22phox ameliorates inflammatory response in Angiotensin II-induced oxidative stress by regulating MAPK and NF-κB pathways in ARPE-19 cells

Sci Rep. 2015 Sep 29:5:14362. doi: 10.1038/srep14362.

Abstract

Oxidative stress and inflammation are two interrelated biological events implicated in the pathogenesis of many diseases. Reactive oxygen species (ROS) produced under oxidative stress play a key role in pathological conditions. Inhibition of p22phox, an indispensable component of the NADPH oxidase (NOX) complex comprising the main source of ROS, plays a protective role in many ocular conditions by inhibiting the activation of NOXs and the generation of ROS. However, little is understood regarding the role of p22phox in oxidative stress-related inflammation in the eye. We used a p22phox small interfering RNA (siRNA) to transfect the retinal pigment epithelium (RPE)-derived cell line ARPE-19, and human primary RPE (hRPE) cells, then stimulated with Ang II. We observed a potent anti-inflammatory effect and studied the underlying mechanism. Downregulating p22phox resulted in decreased ROS generation, a reduction of NOXs (NOX1, 2, 4) and a decrease in inflammatory cytokine. In addition, p22phox downregulation reduced the activation of the MAPK and NF-κB signaling pathways. We conclude that inhibition of p22phox has an anti-inflammatory effect in Ang II-induced oxidative stress. Suppressing the MAPK and NF-κB pathways is involved in this protective effect. These results suggest that p22phox may provide a promising therapeutic target for oxidative stress-induced ocular inflammation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiotensin II / pharmacology*
  • Cell Line
  • Chemokine CCL2 / antagonists & inhibitors
  • Chemokine CCL2 / genetics
  • Chemokine CCL2 / metabolism
  • Epithelial Cells / cytology
  • Epithelial Cells / drug effects*
  • Epithelial Cells / metabolism
  • Gene Expression Regulation
  • Humans
  • Inflammation
  • Interleukin-6 / antagonists & inhibitors
  • Interleukin-6 / genetics
  • Interleukin-6 / metabolism
  • Interleukin-8 / antagonists & inhibitors
  • Interleukin-8 / genetics
  • Interleukin-8 / metabolism
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism
  • Mitogen-Activated Protein Kinase 1 / genetics
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Mitogen-Activated Protein Kinase 3 / genetics
  • Mitogen-Activated Protein Kinase 3 / metabolism
  • NADPH Oxidase 1
  • NADPH Oxidase 2
  • NADPH Oxidase 4
  • NADPH Oxidases / antagonists & inhibitors*
  • NADPH Oxidases / genetics
  • NADPH Oxidases / metabolism
  • NF-kappa B / antagonists & inhibitors*
  • NF-kappa B / genetics
  • NF-kappa B / metabolism
  • Oxidative Stress
  • Primary Cell Culture
  • RNA, Small Interfering / genetics*
  • RNA, Small Interfering / metabolism
  • Retinal Pigment Epithelium / cytology
  • Retinal Pigment Epithelium / drug effects
  • Retinal Pigment Epithelium / metabolism
  • Signal Transduction
  • p38 Mitogen-Activated Protein Kinases / antagonists & inhibitors*
  • p38 Mitogen-Activated Protein Kinases / genetics
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • CCL2 protein, human
  • Chemokine CCL2
  • IL6 protein, human
  • Interleukin-6
  • Interleukin-8
  • Membrane Glycoproteins
  • NF-kappa B
  • RNA, Small Interfering
  • Angiotensin II
  • CYBB protein, human
  • NADPH Oxidase 1
  • NADPH Oxidase 2
  • NADPH Oxidase 4
  • NADPH Oxidases
  • NOX1 protein, human
  • NOX4 protein, human
  • CYBA protein, human
  • MAPK1 protein, human
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • p38 Mitogen-Activated Protein Kinases