Inhibitory effects of citronellol and geraniol on nitric oxide and prostaglandin E₂production in macrophages

Planta Med. 2010 Oct;76(15):1666-71. doi: 10.1055/s-0030-1249947. Epub 2010 May 26.

Abstract

Geranium oil has been used traditionally for diarrhea, dermatitis, and intestinal inflammation in East Asia. The aim of this study was to determine the effects of geranium oil's characteristic components, citronellol and geraniol, on lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production in RAW 264.7 macrophages. Citronellol and geraniol suppressed NO and PGE(2) production in a dose-dependent manner. The inhibitory efficacy of geraniol was concomitant with decreases in protein and mRNA expression levels of inducible nitric oxide synthase (iNOS), whereas citronellol inhibited only iNOS enzymatic activity. By adding citronellol and geraniol, the LPS-induced cyclooxygenase-2 (COX-2) protein and mRNA expression levels were significantly attenuated, whereas cytosolic degradation of I κB α and upregulation of NF-κB p65 in the nucleus were reversed. These results suggested that citronellol and geraniol exhibit anti-inflammatory activities, supporting their common use and demonstrating their therapeutic potential for inflammation-associated disorders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyclic Monoterpenes
  • Animals
  • Cell Line
  • Cyclooxygenase 2 / metabolism
  • Dinoprostone / metabolism*
  • Geranium / chemistry*
  • Intramolecular Oxidoreductases / metabolism
  • Lipopolysaccharides / pharmacology
  • Macrophages / drug effects*
  • Macrophages / metabolism
  • Mice
  • Monoterpenes / chemistry
  • Monoterpenes / pharmacology*
  • Nitric Oxide / metabolism*
  • Nitric Oxide Synthase Type II / metabolism
  • Prostaglandin-E Synthases
  • Protein Biosynthesis / drug effects
  • RNA, Messenger / metabolism
  • Terpenes / chemistry
  • Terpenes / pharmacology*

Substances

  • Acyclic Monoterpenes
  • Lipopolysaccharides
  • Monoterpenes
  • RNA, Messenger
  • Terpenes
  • Nitric Oxide
  • Nitric Oxide Synthase Type II
  • Nos2 protein, mouse
  • Ptgs2 protein, mouse
  • Cyclooxygenase 2
  • Intramolecular Oxidoreductases
  • Prostaglandin-E Synthases
  • Dinoprostone
  • geraniol
  • citronellol