Exogenous Nitric Oxide (NO) Interferes with Lead (Pb)-Induced Toxicity by Detoxifying Reactive Oxygen Species in Hydroponically Grown Wheat (Triticum aestivum) Roots

PLoS One. 2015 Sep 24;10(9):e0138713. doi: 10.1371/journal.pone.0138713. eCollection 2015.

Abstract

Nitric Oxide (NO) is a bioactive signaling molecule that mediates a variety of biotic and abiotic stresses. The present study investigated the role of NO (as SNP [sodium nitroprusside]) in ameliorating lead (Pb)-toxicity in Triticum aestivum (wheat) roots. Pb (50 and 250 μM) alone and in combination with SNP (100 μM) was given to hydroponically grown wheat roots for a period of 0-8 h. NO supplementation reduced the accumulation of oxidative stress markers (malondialdehyde, conjugated dienes, hydroxyl ions and superoxide anion) and decreased the antioxidant enzyme activity in wheat roots particularly up to 6 h, thereby suggesting its role as an antioxidant. NO ameliorated Pb-induced membrane damage in wheat roots as evidenced by decreased ion-leakage and in situ histochemical localization. Pb-exposure significantly decreased in vivo NO level. The study concludes that exogenous NO partially ameliorates Pb-toxicity, but could not restore the plant growth on prolonged Pb-exposure.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Membrane Permeability / drug effects
  • Electrophoresis, Polyacrylamide Gel
  • Hydrogen Peroxide / metabolism
  • Hydroponics*
  • Lead / toxicity*
  • Lipid Peroxidation / drug effects
  • Nitric Oxide / pharmacology*
  • Nitroprusside / pharmacology
  • Plant Roots / drug effects
  • Plant Roots / enzymology
  • Plant Roots / growth & development*
  • Plant Roots / metabolism*
  • Reactive Oxygen Species / metabolism*
  • Seedlings / drug effects
  • Seedlings / growth & development
  • Triticum / drug effects
  • Triticum / growth & development
  • Triticum / metabolism*

Substances

  • Reactive Oxygen Species
  • Nitroprusside
  • Lead
  • Nitric Oxide
  • Hydrogen Peroxide

Grants and funding

Gurpreet Kaur and Priyanka Mahajan received funding from University Grants Commission (UGC), India, and Council for Scientific and Industrial Research (CSIR), India, respectively.