CYP2J2 Expression in Adult Ventricular Myocytes Protects Against Reactive Oxygen Species Toxicity

Drug Metab Dispos. 2018 Apr;46(4):380-386. doi: 10.1124/dmd.117.078840. Epub 2018 Jan 17.

Abstract

Cytochrome P450 2J2 isoform (CYP2J2) is a drug-metabolizing enzyme that is highly expressed in adult ventricular myocytes. It is responsible for the bioactivation of arachidonic acid (AA) into epoxyeicosatrienoic acids (EETs). EETs are biologically active signaling compounds that protect against disease progression, particularly in cardiovascular diseases. As a drug-metabolizing enzyme, CYP2J2 is susceptible to drug interactions that could lead to cardiotoxicity. CYP2J2 has been shown to be resistant to induction by canonical CYP inducers such as phenytoin and rifampin. It is, however, unknown how cellular stresses augment CYP2J2 expression. Here, we determine the effects of oxidative stress on gene expression in adult ventricular myocytes. Further, we assess the consequences of CYP2J2 inhibition and CYP2J2 silencing on cells when levels of reactive oxygen species (ROS) are elevated. Findings indicate that CYP2J2 expression increases in response to external ROS or when internal ROS levels are elevated. In addition, cell survival decreases with ROS exposure when CYP2J2 is chemically inhibited or when CYP2J2 expression is reduced using small interfering RNA. These effects are mitigated with external addition of EETs to the cells. Finally, we determined the results of external EETs on gene expression and show that only two of the four regioisomers cause an increase in HMOX1 expression. This work is the first to determine the consequence of cellular stress, specifically high ROS levels, on CYP2J2 expression in human ventricular myocytes and discusses how this enzyme may play an important role in response to cardiac oxidative stress.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Cell Survival / physiology
  • Cells, Cultured
  • Cytochrome P-450 CYP2J2
  • Cytochrome P-450 Enzyme System / metabolism*
  • Drug Interactions / physiology
  • Gene Expression / physiology
  • Heme Oxygenase-1 / metabolism
  • Humans
  • Myocytes, Cardiac / metabolism*
  • Oxidation-Reduction
  • Oxidative Stress / physiology
  • RNA, Small Interfering / metabolism
  • Reactive Oxygen Species / metabolism*

Substances

  • CYP2J2 protein, human
  • RNA, Small Interfering
  • Reactive Oxygen Species
  • Cytochrome P-450 Enzyme System
  • Cytochrome P-450 CYP2J2
  • Heme Oxygenase-1